Philippe Soyer

To prospectively evaluate the effectiveness and safety of selective embolization of the uterine arteries in the management of symptomatic uterine leiomyoma.Eighty consecutive women (mean age, 44.7 years) with symptomatic uterine leiomyoma, none of whom desired future pregnancy, underwent superselective embolization of the uterine arteries with polyvinyl alcohol particles. In all women, arterial embolization was performed because of persistent, fibroid-related menorrhagia after failure of hormonal therapy. Follow-up consisted of office visits at 2, 6, 12, and 24 months and of ultrasonography at 2 and 6 months after the procedure.Bilateral embolization of the uterine arteries was performed in 76 women; unilateral embolization, in four women. Menorrhagia disappeared in 72 (90%) women. In five (6%) women (including three women with unilateral embolization), clinical improvement was not observed, and myomectomy was needed. In one woman with a large submucosal uterine leiomyoma, hysterectomy was needed because of septic uterine necrosis. Normal menstruation resumed in all but six women. Full-term pregnancy occurred in three women after the procedure.Superselective arterial embolization of the uterine arteries is an effective means of controlling symptomatic uterine leiomyoma. However, the ideal embolic regimen remains to be determined.

Agreement between observers (i.e., inter-rater agreement) can be quantified with various criteria but their appropriate selections are critical. When the measure is qualitative (nominal or ordinal), the proportion of agreement or the kappa coefficient should be used to evaluate inter-rater consistency (i.e., inter-rater reliability). The kappa coefficient is more meaningful that the raw percentage of agreement, because the latter does not account for agreements due to chance alone. When the measures are quantitative, the intraclass correlation coefficient (ICC) should be used to assess agreement but this should be done with care because there are different ICCs so that it is important to describe the model and type of ICC being used. The Bland-Altman method can be used to assess consistency and conformity but its use should be restricted to comparison of two raters.

Advances in image quality over the past few years, mainly due to refinements in hardware and coil systems, have made diffusion-weighted ( DW diffusion weighted ) magnetic resonance (MR) imaging a promising technique for the detection and characterization of pancreatic conditions. DW diffusion weighted MR imaging can be routinely implemented in clinical protocols, as it can be performed relatively quickly, does not require administration of gadolinium-based contrast agents, and enables qualitative and quantitative assessment of tissue diffusivity (diffusion coefficients). In this review, acquisition parameters, postprocessing, and quantification methods applied to pancreatic DW diffusion weighted MR imaging will be discussed. The current common clinical uses of DW diffusion weighted MR imaging (ie, pancreatic lesion detection and characterization) and the less-common applications of DW diffusion weighted MR imaging used for the diagnosis of pancreatic parenchymal diseases will be reviewed. Also, the limitations of the technique, mainly image quality and reproducibility of diffusion parameters, as well as future directions for pancreatic DW diffusion weighted MR imaging will be discussed. The utility of apparent diffusion coefficient ( ADC apparent diffusion coefficient ) measurement for the characterization of pancreatic lesions is now well accepted but there are a number of limitations. Future well-designed, multicenter studies are needed to better determine the most appropriate use of ADC apparent diffusion coefficient in the area of pancreatic disease. © RSNA, 2015 Online supplemental material is available for this article.

Artificial intelligence has demonstrated utility and is increasingly being used in the field of radiology. The use of generative pre-trained transformer (GPT)-based models has the potential to revolutionize the field of radiology, offering new possibilities for improving accuracy, efficiency, and patient outcome. Current applications of GPT-based models in radiology include report generation, educational support, clinical decision support, patient communication, and data analysis. As these models continue to advance and improve, it is likely that more innovative uses for GPT-based models in the field of radiology at large will be developed, further enhancing the role of technology in the diagnostic process. ChatGPT is a variant of GPT that is specifically fine-tuned for conversational language understanding and generation. This article reports some answers provided by ChatGPT to various questions that radiologists may have regarding ChatGPT and identifies the potential benefits ChatGPT may offer in their daily practice but also current limitations. Similar to other applications of artificial intelligence in the field of imaging, further formal validation of ChatGPT is required.

The purpose of this study was to compare the performance of an artificial intelligence (AI) solution to that of a senior general radiologist for bone age assessment.Anteroposterior hand radiographs of eight boys and eight girls from each age interval between five and 17 year-old from four different radiology departments were retrospectively collected. Two board-certified pediatric radiologists with knowledge of the sex and chronological age of the patients independently estimated the Greulich and Pyle bone age to determine the standard of reference. A senior general radiologist not specialized in pediatric radiology (further referred to as “the reader”) then determined the bone age with knowledge of the sex and chronological age. The results of the reader were then compared to those of the AI solution using mean absolute error (MAE) in age estimation.The study dataset included a total of 206 patients (102 boys of mean chronological age of 10.9 ± 3.7 [SD] years, 104 girls of mean chronological age of 11 ± 3.7 [SD] years). For both sexes, the AI algorithm showed a significantly lower MAE than the reader (P < 0.007). In boys, the MAE was 0.488 years (95% confidence interval [CI]: 0.28–0.44; r2 = 0.978) for the AI algorithm and 0.771 years (95% CI: 0.64–0.90; r2 = 0.94) for the reader. In girls, the MAE was 0.494 years (95% CI: 0.41–0.56; r2 = 0.973) for the AI algorithm and 0.673 years (95% CI: 0.54–0.81; r2 = 0.934) for the reader.The AI solution better estimates the Greulich and Pyle bone age than a general radiologist does.

The emergence of massively parallel yet affordable computing devices has been a game changer for research in the field of artificial intelligence (AI). In addition, dramatic investment from the web giants has fostered the development of a high-quality software stack. Going forward, the combination of faster computers with dedicated software libraries and the widespread availability of data has opened the door to more flexibility in the design of AI models. Radiomics is a process used to discover new imaging biomarkers that has multiple applications in radiology and can be used in conjunction with AI. AI can be used throughout the various processes of diagnostic imaging, including data acquisition, reconstruction, analysis and reporting. Today, the concept of "AI-augmented" radiologists is preferred to the theory of the replacement of radiologists by AI in many indications. Current evidence bolsters the assumption that AI-assisted radiologists work better and faster. Interventional radiology becomes a data-rich specialty where the entire procedure is fully recorded in a standardized DICOM format and accessible via standard picture archiving and communication systems. No other interventional specialty can bolster such readiness. In this setting, interventional radiology could lead the development of AI-powered applications in the broader interventional community. This article provides an update on the current status of radiomics and AI research, analyzes upcoming challenges and also discusses the main applications in AI in interventional radiology to help radiologists better understand and criticize articles reporting AI in medical imaging.

PURPOSE: To evaluate the accuracy of spiral computed tomography (CT) in assessing the resectability of small pancreatic ductal adenocarcinoma and to correlate the CT findings with histopathologic and surgical findings. MATERIALS AND METHODS: Spiral CT scans obtained in 64 patients who underwent surgery for potentially resectable pancreatic adenocarcinoma were prospectively assessed for tumor resectability. CT findings were correlated with surgically assessed extent of tumor and pathologic findings. RESULTS: Fifty-seven (89%) of 64 carcinomas were detected with spiral CT. Twenty-four carcinomas were resectable at surgery and 40 were not. The average size of resectable tumors was 3.1 cm (range, 1.0-7.5 cm). The overall accuracy of spiral CT for assessing resectability was 70%. Of resected tumors, 14 were hypoattenuating compared with the remaining pancreas and 10 were isoattenuating. Eleven tumors showed neointimal proliferation in arterioles at histologic examination. CONCLUSION: Further progress in preoperative staging of pancreatic ductal adenocarcinoma with spiral CT should be directed toward improving detection of small pancreatic tumors and assessment of early metastatic disease.

Benign hepatic and biliary tumors can present a difficult diagnostic challenge. Spiral computed tomography (CT) and magnetic resonance (MR) imaging are useful in the detection and characterization of these tumors. Imaging characteristics of lesions such as hepatic cyst, hemangioma, focal nodular hyperplasia (FNH), and hepatic adenoma are well known. Hepatic cysts demonstrate water attenuation at CT, are isointense relative to water at MR imaging, and do not enhance after intravenous administration of contrast material. Hemangiomas demonstrate characteristic nodular peripheral enhancement on early-phase images with subsequent fill-in centrally at both modalities. FNH classically demonstrates intense early enhancement with washout on delayed images. Although hepatic adenoma can also demonstrate intense early enhancement, it has a tendency to bleed and thus often appears more heterogeneous than FNH due to hemorrhage. Benign hepatic tumors that are less well described in the imaging literature include hepatic lipoma or angiomyolipoma, infantile hemangioendothelioma, and mesenchymal hamartoma. Hepatic lipoma has fat attenuation at CT, is isointense relative to fat at MR imaging, and does not enhance after intravenous administration of contrast material. Hepatic angiomyolipomas contain a variable amount of soft tissue in addition to fat and may therefore demonstrate enhancement at both modalities. The CT and MR imaging appearances of infantile hemangioma are similar to those of adult hemangioma. Infantile hemangioendothelioma occurs in infants under 6 months of age and is typically a larger lesion. Mesenchymal hamartoma also occurs in children, and its imaging appearance depends on the presence of stromal elements and the protein content of the cyst fluid. Familiarity with these imaging features can help distinguish particular disease entities.

To prospectively evaluate the efficacy and safety of emergency selective arterial embolization in the management of intractable primary postpartum hemorrhage.Twenty-seven consecutively seen women with life-threatening primary postpartum hemorrhage underwent uterine embolization. In all cases, hemostatic embolization was performed because of intractable hemorrhage that could not be controlled with vaginal packing and administration of uterotonic drugs. The mean hemoglobin level before embolization was 7.48 g/dL +/- 2.39 (74.8 g/L +/- 23.9) (1 standard deviation). Hysterectomy performed in two patients before embolization failed to stop the bleeding.Angiography revealed extravasation in nine patients and spasm of the branches of the internal iliac artery in five. The procedure consisted of embolization of uterine (n = 46), vaginal (n = 5), or ovarian (n = 2) arteries or anterior division of internal iliac arteries (n = 8). Immediate disappearance or dramatic diminution of external bleeding was observed in all cases. Two patients needed repeated embolization the next day. No major complication related to embolization was found. In one patient with placenta accreta, delayed hysterectomy was necessary. Normal menstruation resumed in all women except the two who underwent hysterectomy. One woman became pregnant after embolization.Emergency arterial embolization is a safe and effective means of control of primary postpartum hemorrhage. The procedure obviates high-risk surgery and allows maintenance of reproductive ability.

To prospectively evaluate multi-detector row helical computed tomographic (CT) enteroclysis for the depiction of small-bowel diseases.The study group included 107 patients who were suspected of having small-bowel tumor (n = 8), active inflammatory small-bowel disease (n = 18), unexplained gastrointestinal bleeding (n = 36), refractory celiac sprue (n = 14), and low-grade small-bowel obstruction (n = 31). A nasoenteric tube was positioned into the duodenojejunal junction by using fluoroscopic guidance and water was infused with a pressure-controlled pump. After intravenous administration of 120 mL of iodinated contrast material, multi-detector row helical CT enteroclysis images were obtained with 4 x 2.5 mm collimation (four detector rows and 2.5-mm section thickness). Multi-detector row helical CT enteroclysis findings were analyzed by two readers working in consensus. Findings were compared with the results of endoscopy, enteroscopy, videocapsule endoscopy, histopathologic analysis, or clinical follow-up.Multi-detector row helical CT enteroclysis was well tolerated in 106 patients; one patient complained of abdominal pain after the examination. Multi-detector row helical CT enteroclysis allowed the diagnosis of small-bowel masses (n = 21), active Crohn disease (n = 9), small-bowel tuberculosis (n = 2), small-bowel lymphoma complicating celiac disease (n = 4), and confirmed low-grade small-bowel obstruction (n = 12). Multi-detector row helical CT enteroclysis demonstrated normal findings in 60 patients. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of multi-detector row helical CT enteroclysis were 100%, 95%, 97%, 94%, and 100%, respectively.Multi-detector row helical CT enteroclysis allows depiction of small-bowel diseases in patients suspected of having small-bowel conditions.

To evaluate the efficacy and safety of selective arterial embolization of the uterine arteries in the management of intractable delayed postpartum hemorrhage.Fourteen consecutive women with secondary postpartum hemorrhage were treated with selective embolization of the uterine arteries. In all cases, hemostatic embolization was performed because of intractable hemorrhage that could not be controlled with the administration of uterotonic drugs or with uterine curettage.The causes of bleeding included genital tract tears in four women and endometritis in eight women; the endometritis was associated with proved, retained portions of placenta in four women. In two women, no evident cause of bleeding was found before angiography. Angiography revealed extravasation in three women. A false aneurysm of the uterine artery was found in two women. In one patient, an arteriovenous fistula was observed. Immediate resolution of external bleeding was observed in all women. No complication related to embolization was found. Normal menstruation resumed in all women.Selective arterial embolization of the uterine arteries is a safe and effective means of controlling secondary postpartum hemorrhage.

To evaluate gadobenate dimeglumine (Gd-BOPTA) for dynamic and delayed magnetic resonance (MR) imaging of focal liver lesions.In 126 of 214 patients, MR imaging was performed before Gd-BOPTA administration, immediately after bolus administration of a 0.05- mmol/kg dose of Gd-BOPTA, and 60-120 minutes after an additional intravenously infused 0.05-mmol/kg dose. In 88 patients, imaging was performed before and 60-120 minutes after a single, intravenously infused 0.1-mmol/kg dose. T1- and T2-weighted spin-echo and T1-weighted gradient-echo images were acquired. On-site and blinded off-site reviewers prospectively evaluated all images. Intraoperative ultrasonography, computed tomography (CT) during arterial portography, and/or CT with iodized oil served as the reference methods in 110 patients.Significantly more lesions were detected on combined pre- and postcontrast images compared with on precontrast images alone (P <. 01). All reviewers reported a decreased mean size of the smallest detected lesion and improved lesion conspicuity on postcontrast images. All on-site reviewers and two off-site reviewers reported increased overall diagnostic confidence (P <.01). Additional lesion characterization information was provided on up to 109 (59%) of 184 delayed images and for up to 50 (42%) of 118 patients in whom dynamic images were assessed. Gd-BOPTA would have helped change the diagnosis in 99 (47%) of 209 cases and affected patient treatment in 408 (23%) of 209 cases.Gd-BOPTA increases liver lesion conspicuity and detectability and aids in the characterization of lesions.

Arterial anatomy of the female genital tract: variations and relevance to transcatheter embolization of the uterus.J P Pelage, O Le Dref, P Soyer, D Jacob, M Kardache, H Dahan, J P Lassau and R RymerAudio Available | Share

The use of cross-sectional imaging techniques for the noninvasive evaluation of small-bowel disorders is increasing. The effectiveness of magnetic resonance (MR) enterography for the evaluation of Crohn disease, in particular, is well described in the literature. In addition, MR enterography has an evolving though less well documented role to play in the evaluation of other small-bowel diseases, including various benign and malignant neoplasms arising in isolation or in polyposis syndromes such as Peutz-Jeghers, inflammatory conditions such as vasculitis and treatment-induced enteritis, infectious processes, celiac disease, diverticular disease, systemic sclerosis, and bowel duplication. MR enterography may be useful also for the evaluation of intermittent and low-grade small-bowel obstructions. Advantages of MR imaging over computed tomography (CT) for enterographic evaluations include superb contrast resolution, lack of associated exposure to ionizing radiation, ability to acquire multiplanar primary image datasets, ability to acquire sequential image series over a long acquisition time, multiphasic imaging capability, and use of intravenous contrast media with better safety profiles. MR enterography also allows dynamic evaluations of small-bowel peristalsis and distensibility of areas of luminal narrowing and intraluminal masses by repeating sequences at different intervals after administering an additional amount of the oral contrast medium. Limitations of MR enterography in comparison with CT include higher cost, less availability, more variable image quality, and lower spatial resolution. The advantages and disadvantages of MR enterography performed with ingestion of the oral contrast medium relative to MR enteroclysis performed with infusion of the oral contrast medium through a nasoenteric tube are less certain.

Purpose The objective of this study was to build and validate a radiomic signature to predict early a poor outcome using baseline and 2-month evaluation CT and to compare it to the RECIST1·1 and morphological criteria defined by changes in homogeneity and borders. Methods This study is an ancillary study from the PRODIGE-9 multicentre prospective study for which 491 patients with metastatic colorectal cancer (mCRC) treated by 5-fluorouracil, leucovorin and irinotecan (FOLFIRI) and bevacizumab had been analysed. In 230 patients, computed texture analysis was performed on the dominant liver lesion (DLL) at baseline and 2 months after chemotherapy. RECIST1·1 evaluation was performed at 6 months. A radiomic signature (Survival PrEdiction in patients treated by FOLFIRI and bevacizumab for mCRC using contrast-enhanced CT TextuRe Analysis (SPECTRA) Score) combining the significant predictive features was built using multivariable Cox analysis in 120 patients, then locked, and validated in 110 patients. Overall survival (OS) was estimated with the Kaplan-Meier method and compared between groups with the logrank test. An external validation was performed in another cohort of 40 patients from the PRODIGE 20 Trial. Results In the training cohort, the significant predictive features for OS were: decrease in sum of the target liver lesions (STL), (adjusted hasard-ratio(aHR)=13·7, p=1·93×10 –7 ), decrease in kurtosis (ssf=4) (aHR=1·08, p=0·001) and high baseline density of DLL, (aHR=0·98, p&lt;0·001). Patients with a SPECTRA Score &gt;0·02 had a lower OS in the training cohort (p&lt;0·0001), in the validation cohort (p&lt;0·0008) and in the external validation cohort (p=0·0027). SPECTRA Score at 2 months had the same prognostic value as RECIST at 6 months, while non-response according to RECIST1·1 at 2 months was not associated with a lower OS in the validation cohort (p=0·238). Morphological response was not associated with OS (p=0·41). Conclusion A radiomic signature (combining decrease in STL, density and computed texture analysis of the DLL) at baseline and 2-month CT was able to predict OS, and identify good responders better than RECIST1.1 criteria in patients with mCRC treated by FOLFIRI and bevacizumab as a first-line treatment. This tool should now be validated by further prospective studies. Trial registration Clinicaltrial.gov identifier of the PRODIGE 9 study: NCT00952029 . Clinicaltrial.gov identifier of the PRODIGE 20 study: NCT01900717 .

The aim was to determine the incremental value of MRI compared with CT in the preoperative estimation of the peritoneal carcinomatosis index (PCI).CT and MRI examinations of patients with peritoneal carcinomatosis were evaluated. CT images were first analysed by two observers who determined a first PCI (PCICT ). Then, the two observers reviewed MRI examinations in combination with CT and determined a second PCI (PCICT+MRI ). The sensitivity and negative predictive value of the two imaging sets were determined using surgery as a reference standard (PCIRef ).CT plus MRI was more accurate in predicting the surgical PCI than CT alone. The absolute difference between PCICT+MRI and PCIRef was lower than that between PCICT and PCIRef (mean(s.d.) 3·96(4·10) versus 4·89(4·73); P = 0·010). The number of true-positive findings increased from 106 to 125 for reader 1 and from 117 to 132 for reader 2 with the adjunct of MRI. For both readers, an increased sensitivity was obtained when both MRI and CT were used (from 63 to 81 per cent for reader 1; from 44 to 81 per cent for reader 2). The increase in sensitivity was greater for patients with a moderate volume of disease.The combination of CT and MRI improved the preoperative estimation of PCI compared with CT alone.

Over the past years, technological improvements and refinements in magnetic resonance imaging (MRI) hardware have made high-quality diffusion-weighted imaging (DWI) routinely possible for the bowel. DWI is promising for the detection and characterization of lesions in Crohn's disease (CD) and has been advocated as an alternative to intravenous gadolinium-based contrast agents. Furthermore, quantification using the apparent diffusion coefficient may have value as a biomarker of CD activity and has shown promise. In this article we critically review the literature pertaining to the value of DWI in CD for detection, characterization, and quantification of disease activity and complications. Although the body of supportive evidence is growing, it is clear that well-designed, multicenter studies are required before the role of DWI in clinical practice can be fully established. J. Magn. Reson. Imaging 2016;44:1381-1396.

The purpose of this study was to compare the performance of an artificial intelligence (AI) solution to that of a senior general radiologist for bone age assessment.Anteroposterior hand radiographs of eight boys and eight girls from each age interval between five and 17 year-old from four different radiology departments were retrospectively collected. Two board-certified pediatric radiologists with knowledge of the sex and chronological age of the patients independently estimated the Greulich and Pyle bone age to determine the standard of reference. A senior general radiologist not specialized in pediatric radiology (further referred to as “the reader”) then determined the bone age with knowledge of the sex and chronological age. The results of the reader were then compared to those of the AI solution using mean absolute error (MAE) in age estimation.The study dataset included a total of 206 patients (102 boys of mean chronological age of 10.9 ± 3.7 [SD] years, 104 girls of mean chronological age of 11 ± 3.7 [SD] years). For both sexes, the AI algorithm showed a significantly lower MAE than the reader (P < 0.007). In boys, the MAE was 0.488 years (95% confidence interval [CI]: 0.28–0.44; r2 = 0.978) for the AI algorithm and 0.771 years (95% CI: 0.64–0.90; r2 = 0.94) for the reader. In girls, the MAE was 0.494 years (95% CI: 0.41–0.56; r2 = 0.973) for the AI algorithm and 0.673 years (95% CI: 0.54–0.81; r2 = 0.934) for the reader.The AI solution better estimates the Greulich and Pyle bone age than a general radiologist does.

Background Stratifying high-risk histopathologic features in endometrial carcinoma is important for treatment planning. Radiomics analysis at preoperative MRI holds potential to identify high-risk phenotypes. Purpose To evaluate the performance of multiparametric MRI three-dimensional radiomics-based machine learning models for differentiating low- from high-risk histopathologic markers-deep myometrial invasion (MI), lymphovascular space invasion (LVSI), and high-grade status-and advanced-stage endometrial carcinoma. Materials and Methods This dual-center retrospective study included women with histologically proven endometrial carcinoma who underwent 1.5-T MRI before hysterectomy between January 2011 and July 2015. Exclusion criteria were tumor diameter less than 1 cm, missing MRI sequences or histopathology reports, neoadjuvant therapy, and malignant neoplasms other than endometrial carcinoma. Three-dimensional radiomics features were extracted after tumor segmentation at MRI (T2-weighted, diffusion-weighted, and dynamic contrast-enhanced MRI). Predictive features were selected in the training set with use of random forest (RF) models for each end point, and trained RF models were applied to the external test set. Five board-certified radiologists conducted MRI-based staging and deep MI assessment in the training set. Areas under the receiver operating characteristic curve (AUCs) were reported with balanced accuracies, and radiologists' readings were compared with radiomics with use of McNemar tests. Results In total, 157 women were included: 94 at the first institution (training set; mean age, 66 years ± 11 [SD]) and 63 at the second institution (test set; 67 years ± 12). RF models dichotomizing deep MI, LVSI, high grade, and International Federation of Gynecology and Obstetrics (FIGO) stage led to AUCs of 0.81 (95% CI: 0.68, 0.88), 0.80 (95% CI: 0.67, 0.93), 0.74 (95% CI: 0.61, 0.86), and 0.84 (95% CI: 0.72, 0.92), respectively, in the test set. In the training set, radiomics provided increased performance compared with radiologists' readings for identifying deep MI (balanced accuracy, 86% vs 79%; P = .03), while no evidence of a difference was observed in performance for advanced FIGO stage (80% vs 78%; P = .27). Conclusion Three-dimensional radiomics can stratify patients by using preoperative MRI according to high-risk histopathologic end points in endometrial carcinoma and provide nonsignificantly different or higher performance than radiologists in identifying advanced stage and deep myometrial invasion, respectively. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Kido and Nishio in this issue.

Artificial intelligence (AI) has been a very active research topic over the last years and thoracic imaging has particularly benefited from the development of AI and in particular deep learning. We have now entered a phase of adopting AI into clinical practice. The objective of this article was to review the current applications and perspectives of AI in thoracic oncology. For pulmonary nodule detection, computer-aided detection (CADe) tools have been commercially available since the early 2000s. The more recent rise of deep learning and the availability of large annotated lung nodule datasets have allowed the development of new CADe tools with fewer false-positive results per examination. Classical machine learning and deep-learning methods were also used for pulmonary nodule segmentation allowing nodule volumetry and pulmonary nodule characterization. For pulmonary nodule characterization, radiomics and deep-learning approaches were used. Data from the National Lung Cancer Screening Trial (NLST) allowed the development of several computer-aided diagnostic (CADx) tools for diagnosing lung cancer on chest computed tomography. Finally, AI has been used as a means to perform virtual biopsies and to predict response to treatment or survival. Thus, many detection, characterization and stratification tools have been proposed, some of which are commercially available.

Artificial intelligence (AI) applications in radiology have been rising exponentially in the last decade. Although AI has found usage in various areas of healthcare, its utilization in the emergency department (ED) as a tool for emergency radiologists shows great promise towards easing some of the challenges faced daily. There have been numerous reported studies examining the application of AI-based algorithms in identifying common ED conditions to ensure more rapid reporting and in turn quicker patient care. In addition to interpretive applications, AI assists with many of the non-interpretive tasks that are encountered every day by emergency radiologists. These include, but are not limited to, protocolling, image quality control and workflow prioritization. AI continues to face challenges such as physician uptake or costs, but is a long-term investment that shows great potential to relieve many difficulties faced by emergency radiologists and ultimately improve patient outcomes. This review sums up the current advances of AI in emergency radiology, including current diagnostic applications (interpretive) and applications that stretch beyond imaging (non-interpretive), analyzes current drawbacks of AI in emergency radiology and discusses future challenges.

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer and currently the third-leading cause of cancer-related death worldwide. Recently, artificial intelligence (AI) has emerged as an important tool to improve clinical management of HCC, including for diagnosis, prognostication and evaluation of treatment response. Different AI approaches, such as machine learning and deep learning, are both based on the concept of developing prediction algorithms from large amounts of data, or big data. The era of digital medicine has led to a rapidly expanding amount of routinely collected health data which can be leveraged for the development of AI models. Various studies have constructed AI models by using features extracted from ultrasound imaging, computed tomography imaging and magnetic resonance imaging. Most of these models have used convolutional neural networks. These tools have shown promising results for HCC detection, characterization of liver lesions and liver/tumor segmentation. Regarding treatment, studies have outlined a role for AI in evaluation of treatment response and improvement of pre-treatment planning. Several challenges remain to fully integrate AI models in clinical practice. Future research is still needed to robustly evaluate AI algorithms in prospective trials, and improve interpretability, generalizability and transparency. If such challenges can be overcome, AI has the potential to profoundly change the management of patients with HCC. The purpose of this review was to sum up current evidence on AI approaches using imaging for the clinical management of HCC.

Purpose: The purpose of this study was to analyze the answers provided by ChatGPT to various questions in the field of interventional radiology (IR) and compare their correctness to a consensus of three interventional radiologists. Materials and Methods. Twenty questions were proposed to the online chat based ChatGPT about interventional radiology as indications for exams, complications and technical points. Answers were independently evaluated by 3 experts in interventional radiology with 10, 15 and 30 years or experiences and classified as correct, almost correct, or wrong. Results: Considering the consensus between the two IR, nine (9/20; 45%) were considered wrong, three (3/20; 15%) were considered almost correct and eight (8/20; 40%) were considered correct. Conclusion: ChatGPT can be useful in IR but the users must be aware of limitations such as too vague or inaccurate answers for the majority of questions.

Artificial Intelligence (AI) is set to transform medical imaging by leveraging the vast data contained in medical images. Deep learning and radiomics are the two main AI methods currently being applied within radiology. Deep learning uses a layered set of self-correcting algorithms to develop a mathematical model that best fits the data. Radiomics converts imaging data into mineable features such as signal intensity, shape, texture, and higher-order features. Both methods have the potential to improve disease detection, characterization, and prognostication. This article reviews the current status of artificial intelligence in pancreatic imaging and critically appraises the quality of existing evidence using the radiomics quality score.

Interventional radiology shows promises in the field of women's health, particularly in pelvic interventions. This review article discusses the latest advancements in interventional radiology techniques for pelvic conditions affecting women including adenomyosis, abdominal wall endometriosis and uterine leiomyoma. Extraperitoneal endometriosis involving the abdominal wall may be treated by percutaneous thermal ablation, such as cryoablation, whereas uterine leiomyoma and adenomyosis can be managed either using percutaneous thermal ablation or using uterine artery embolization. Continued research and development in interventional radiology will further enhance the minimally-invasive interventions available for women's health, improving outcomes and quality of life for this large patient population of women.

Although small bowel obstruction is a common occurrence, it is essential that this clinical condition be treated properly, that the site, level, and cause of obstruction be determined accurately, and that a tentative prognosis be formulated prior to surgery. The diagnosis of small bowel obstruction is based on a comprehensive approach that includes clinical background, patient history, and results of physical examination and laboratory tests. A variety of radiologic procedures are available to aid in the diagnosis of small bowel obstruction. Recent studies have demonstrated the superiority of CT in revealing the site, level, and cause of obstruction and in demonstrating threatening signs of bowel inviability. CT has proved useful in characterizing small bowel obstruction from extrinsic causes (adhesions, closed loop, strangulation, hernia, extrinsic masses), intrinsic causes (adenocarcinoma, Crohn disease, tuberculosis, radiation enteropathy, intramural hemorrhage, intussusception), intraluminal causes (eg, bezoars), or intestinal malrotation. Conventional radiography was the modality of choice for many years and should remain the initial imaging method in patients with suspected small bowel obstruction. However, the unique capabilities of CT in this setting make this modality an important additional diagnostic tool when specific disease management issues must be addressed.

To compare the respective sensitivities of unenhanced, arterial-dominant, and portal-dominant phase helical computed tomography (CT) in the preoperative depiction of hypovascular hepatic metastases by using intraoperative ultrasonographic (US) and histopathologic findings as the standard of reference.In this prospective study, 32 patients with 59 surgically and histopathologically proved hypovascular hepatic metastases underwent triple-phase helical CT of the liver, which included unenhanced, arterial-dominant, and portal-dominant phase scanning. Images from each phase were separately analyzed by three readers, and disagreements were resolved with consensus readings. The findings on CT images were compared with intraoperative US and histopathologic findings on a lesion-by-lesion basis to determine the sensitivity of each imaging phase. Statistical review of the lesion-by-lesion analysis was performed by using the Wilcoxon rank sum test.Among 59 hepatic metastases, unenhanced, arterial-dominant, and portal-dominant phase helical CT imaging depicted 39 (66.1%; 95% CI: 53.3%, 76.8%), 44 (74.5%; 95% CI: 62.2%, 83.9%), and 54 (91.5%; 95% CI: 81.6%, 96.3%) metastases, respectively. Portal-dominant phase imaging depicted significantly more hypovascular hepatic metastases than did unenhanced (P <.001) or arterial-dominant (P <.01) phase imaging (Wilcoxon test).Preoperative use of triple-phase helical CT in patients with hypovascular hepatic metastases may not be warranted. Portal-dominant phase helical CT imaging allows depiction of significantly more hypovascular hepatic metastases than does imaging during any of the other phases.

A prospective study was performed to determine the impact of preoperative assessment of estimated postoperative liver volume on surgical decision making for liver metastases from colorectal cancer. Assessment of estimated postoperative liver volume was performed before surgery in 25 patients. Mean estimated postoperative liver volume +/- standard deviation (SD) was 697 cm3 +/- 317 (range, 320-1,532 cm3). Mean relative estimated postoperative liver volume +/- SD was 51% +/- 16 (range, 20%-90%). In two patients, relative estimated postoperative liver volumes of less than 35% prevented resection. These two patients underwent preoperative portal vein embolization, which resulted in marked hypertrophy of the unembolized healthy part of the liver and subsequent safe resection. Before surgery, all patients had a relative estimated postoperative liver volume of greater than 35%, and no cases of postoperative liver failure occurred. The results demonstrated that assessment of estimated postoperative liver volume provides vital preoperative data for reducing the risk of postoperative liver failure.

Transjugular liver biopsy is a safe, effective and well-tolerated technique to obtain liver tissue specimens in patients with diffuse liver disease associated with severe coagulopathies or massive ascites. Transjugular liver biopsy is almost always feasible. The use of ultrasonographic guidance for percutaneous puncture of the right internal jugular vein is recommended to decrease the incidence of local cervical minor complications. Semiautomated biopsy devices are very effective in obtaining optimal tissue samples for a precise and definite histological diagnosis with a very low rate of complication. The relative limitations of transjugular liver biopsy are the cost, the radiation dose given to the patient, the increased procedure time by comparison with the more common percutaneous liver biopsy, and the need of a well-trained interventional radiologist.

To compare the capabilities of apparent diffusion coefficient (ADC) and normalized ADC using the pancreatic parenchyma as reference organ in the characterization of focal pancreatic lesions.Thirty-six patients with focal pancreatic lesions (malignant, n=18; benign tumors, n=10; focal pancreatitis, n=8) underwent diffusion-weighted MR imaging (DWI) at 1.5-Tesla using 3 b values (b=0, 400, 800 s/mm(2)). Lesion ADC and normalized lesion ADC (defined as the ratio of lesion ADC to apparently normal adjacent pancreas) were compared between lesion types using nonparametric tests.Significant differences in ADC values were found between malignant (1.150 × 10(-3)mm(2)/s) and benign tumors (2.493 × 10(-3)mm(2)/s) (P=0.004) and between benign tumors and mass-forming pancreatitis (1.160 × 10(-3)mm(2)/s) (P=0.0005) but not between malignant tumors and mass-forming pancreatitis (P=0.1092). Using normalized ADC, significant differences were found between malignant tumors (0.933 × 10(-3)mm(2)/s), benign tumors (1.807 × 10(-3)mm(2)/s) and mass-forming pancreatitis (0.839 × 10(-3)mm(2)/s) (P<0.0001).Our preliminary results suggest that normalizing ADC of focal pancreatic lesions with ADC of apparently normal adjacent pancreatic parenchyma provides higher degrees of characterization of focal pancreatic lesions than the conventional ADC does.

de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Hepatocellular carcinoma (HCC) usually occurs in the setting of liver cirrhosis and more rarely in a healthy liver. Its incidence has increased in the past years, especially in western countries with the rising prevalence of non-alcoholic fatty liver disease. The prognosis of advanced HCC is low. In the first-line setting of advanced HCC, sorafenib, a tyrosine kinase inhibitor, was the only validated treatment for many years. In 2020, the combination of atezolizumab, an immune checkpoint inhibitor, and bevacizumab showed superiority to sorafenib alone in survival, making it the first-line recommended treatment. Regorafenib and lenvatinib, other multikinase inhibitors, were also validated in the second and first-line settings, respectively. Transarterial chemoembolization can be an alternative treatment for patients with intermediate-stage HCC and preserved liver function, including unresectable multinodular HCC without extrahepatic spread. The current challenge in advanced HCC lies in the selection of a patient for the optimal treatment, taking into account the underlying liver disease and liver function. Indeed, all trial patients present with a Child-Pugh score of A, and the optimal approach for other patients is still unclear. Furthermore, the combination of atezolizumab and bevacizumab should be considered in the absence of medical contraindication. Many trials testing immune checkpoint inhibitors in association with anti-angiogenic agents are ongoing, and primary results are promising. The landscape in advanced HCC management is undergoing profound change, and many challenges remain for optimal patient management in the years to come. This review aimed to provide an overview of current systemic treatment options for patients with advanced unresectable HCC who are not candidates for liver-directed therapy.

In the elective field of adrenal imaging, artificial intelligence (AI) can be used for adrenal lesion detection, characterization, hypersecreting syndrome management and patient follow-up. Although a perfect AI tool that includes all required steps from detection to analysis does not exist yet, multiple AI algorithms have been developed and tested with encouraging results. However, AI in this setting is still at an early stage. In this regard, most published studies about AI in adrenal gland imaging report preliminary results that do not have yet daily applications in clinical practice. In this review, recent developments and current results of AI in the field of adrenal imaging are presented. Limitations and future perspectives of AI are discussed.

Gastrointestinal stromal tumors (GISTs) are defined as mesenchymal tumors of the gastrointestinal tract that express positivity for CD117, which is a c-KIT proto-oncogene antigen. Expression of the c-KIT protein, a tyrosine kinase growth factor receptor, allows the distinction between GISTs and other mesenchymal tumors such as leiomyoma, leiomyosarcoma, schwannoma and neurofibroma. GISTs can develop anywhere in the gastrointestinal tract, as well as in the mesentery and omentum. Over the years, the management of GISTs has improved due to a better knowledge of their behaviors and risk or recurrence, the identification of specific mutations and the use of targeted therapies. This has resulted in a better prognosis for patients with GISTs. In parallel, imaging of GISTs has been revolutionized by tremendous progress in the field of detection, characterization, survival prediction and monitoring during therapy. Recently, a particular attention has been given to radiomics for the characterization of GISTs using analysis of quantitative imaging features. In addition, radiomics has currently many applications that are developed in conjunction with artificial intelligence with the aim of better characterizing GISTs and providing a more precise assessment of tumor burden. This article sums up recent advances in computed tomography and magnetic resonance imaging of GISTs in the field of image/data acquisition, tumor detection, tumor characterization, treatment response evaluation, and preoperative planning.

Hepato-pancreato-biliary (HPB) emergencies in patients with cancer encompass an extensive array of various conditions, including primary malignancies that require prompt treatment, associated severe complications, and life-threatening consequences arising from treatment. In patients with cancer, the liver can be affected by chemotherapy-induced hepatotoxicity, veno-occlusive disease, Budd-Chiari syndrome, liver hemorrhage, and other complications arising from cancer therapy with all these complications requiring timely diagnosis and prompt treament. Cholecystitis induced by systemic anticancer therapies can result in severe conquences if not promptly identified and treated. The application of immunotherapy in cancer therapy is associated with cholangitis. Hemobilia, often caused by medical interventions, may require arterial embolization in patients with severe bleeding and hemodynamic instability. Malignant biliary obstruction in patients with biliary cancers may necessitate palliative strategies such as biliary stenting. In pancreatic cancer, patients often miss surgical treatment due to advanced disease stages or distant metastases, leading to potential emergencies at different treatment phases. This comprehensive review underscores the complexities of diagnostic and treatment roles of medical imaging in managing HPB emergencies in patients with cancer. It illustrates the crucial role of imaging techniques, including magnetic resonance imaging, computed tomography and ultrasound, in diagnosing and managing these conditions for timely intervention. It provides essential insights into the critical nature of early diagnosis and intervention in cancer-related HPB emergencies, ultimately impacting patient outcomes and survival rates.

The goals of this study were to describe variations in the intrahepatic portions of the hepatic and portal veins as visualized by helical CT during arterial portography (CTAP) and to examine the surgical implications of these findings.A retrospective review of 69 helical CTAP scans of 69 patients with small hepatic tumors and no evidence of vascular invasion or distortion was done. Axial helical CTAP scans were reviewed to determine the presence, number, and location of intrahepatic portions of the hepatic and portal veins.Among the 60 patients (87%) in whom the right, middle, and left hepatic veins were visualized, 19 (32%) had supernumerary hepatic veins. Right inferior hepatic veins were found in six (9%) of the 69 patients. Variations in intrahepatic portal anatomy were found in four patients (6%) and involved an immediate trifurcation of the portal vein in three patients (4%) and a left main portal vein originating from the right anterior portal branch in one patient (2%).Variations in the intrahepatic portions of the hepatic and portal veins are frequently seen on helical CTAP scans. Recognition of such variations is important in the preoperative evaluation of patients with hepatic tumors because these variations may have implications for tumor resection and for planning the operative approach.

Hepatic metastases from neuroendocrine tumors are often markedly hyperintense on unenhanced T2-weighted MR images, making their appearance similar to that of cavernous hemangiomas. In contrast, cavernous hemangiomas show characteristic enhancement on dynamic gadolinium chelate-enhanced gradient-recalled echo MR images. The purpose of this study was to determine the relative merits of dynamic gadolinium chelate-enhanced gradient-recalled echo MR imaging versus MR imaging with unenhanced spin-echo pulse sequences for distinguishing between hepatic metastases from neuroendocrine tumors and cavernous hemangiomas.The unenhanced spin-echo and dynamic gradient-recalled echo MR images obtained after IV administration of a gadolinium chelate in 28 patients (14 patients with pathologically proven hepatic metastases from neuroendocrine tumors and 14 patients with hepatic cavernous hemangiomas) were reviewed blindly and independently by three interpreters. Unenhanced spin-echo and dynamic gadolinium chelate-enhanced gradient-recalled echo MR images were compared for accuracy in characterizing liver lesions.The most intense enhancement of hepatic metastases from neuroendocrine tumors was observed on early dynamic gadolinium chelate-enhanced gradient-recalled echo MR images; enhancement was peripheral in four patients, global and heterogeneous in seven patients, and global and homogeneous in three patients. On late dynamic gadolinium chelate-enhanced gradient-recalled echo MR images, enhancement of hepatic metastases from neuroendocrine tumors was predominantly peripheral in five patients, global and heterogeneous in five patients, and global and homogeneous in four patients. Differentiation between cavernous hemangiomas and hepatic metastases from neuroendocrine tumors was impossible in five cases with unenhanced spin-echo MR imaging alone, in five cases with dynamic gadolinium chelate-enhanced gradient-recalled echo MR imaging alone, and in no case with the combination of unenhanced spin-echo MR imaging and dynamic gadolinium chelate-enhanced gradient-recalled echo MR imaging. In comparison with unenhanced spin-echo MR imaging alone or dynamic gadolinium chelate-enhanced gradient-recalled echo MR imaging alone, the combination of unenhanced spin-echo MR imaging and dynamic gadolinium chelate-enhanced gradient-recalled echo MR imaging allowed significantly (p < .001) clearer differentiation between hepatic metastases from neuroendocrine tumors and cavernous hemangiomas.Early enhancement and heterogeneity on dynamic gadolinium chelate-enhanced gradient-recalled echo MR images are the most common features of hepatic metastases from neuroendocrine tumors. The combination of unenhanced spin-echo and dynamic gadolinium chelate-enhanced gradient-recalled echo MR images allows more accurate characterization of hepatic metastases from neuroendocrine tumors and clearer differentiation from cavernous hemangiomas.

A retrospective study was performed to determine the causes of false-positive diagnoses based on CT findings obtained during superior mesenteric arterial portography (CT portography) and to correlate the imaging characteristics of the incorrectly diagnosed lesions with their pathologic findings.In a series of 52 patients who had CT portography before surgical exploration of the liver, eight had a total of 10 false-positive findings, yielding a false-positive diagnosis rate of 15%. In eight cases, the false-positive findings from CT portography were correlated with the histologic material obtained during partial hepatic resection or intraoperative biopsies at the corresponding sites.Of the 10 false-positive findings on CT portograms, seven led to false-positive diagnoses of hepatic tumors. Conversely, three nontumorous false-positive findings were erroneously considered to be portal perfusion defects. The final diagnoses based on pathologic findings included focal fatty infiltration of the liver (three), cirrhosis (two), and portal perfusion defect (three). Two false-positive findings for which no histologic correlation was possible were considered to be portal perfusion defects on the basis of intraoperative findings.Recognition of false-positive findings is crucial in the preoperative evaluation of hepatic tumors because the findings may be interpreted as contraindications for surgery in patients who have operable tumors. The pathologic correlations show that several different entities can cause diagnoses based on CT portographic findings to be false-positive. However, differentiating between those entities remains a diagnostic challenge.

To evaluate the accuracy of a fast three-dimensional (3D) reconstruction technique in determining the segmental location of hepatic metastases, 14 patients (40 metastases) were prospectively investigated before surgery with dynamic two-dimensional (2D) computed tomography during sequential arterial portography (CTAP). All patients underwent subsequent hepatic tumor resection within 4 days. After computer-generated mapping of hepatic venous structures with high attenuation and metastases with low attenuation, 3D reconstruction was performed. Thirty-six of the 40 lesions (90%) were detected with 2D and 3D CTAP. The accuracy in determining the segmental location of hepatic metastases was 78% (28 of the 36 metastases) for 2D CTAP and 94% (34 of the 36 metastases) for 3D CTAP. The difference in localization rates between 2D CTAP and 3D CTAP was statistically significant. The 3D CTAP technique provides vital data unattainable with other imaging modalities that improve the preoperative assessment of the resectability of hepatic metastases and allows planning a safer surgical approach.

Preoperative assessment of resectability of hepatic metastases from colonic carcinoma: CT portography vs sonography and dynamic CT.P Soyer, M Levesque, D Elias, G Zeitoun and A RocheAudio Available | Share

Purpose To determine the utility of computed tomographic (CT) enteroclysis for characterization of the status of the anastomotic site in patients with Crohn disease who had previously undergone ileocolic resection. Materials and Methods Written informed consent was prospectively obtained from all patients, and the institutional review board approved the study protocol. CT enteroclysis findings in 40 patients with Crohn disease who had previously undergone ileocolic resection were evaluated independently by two readers. Endoscopic findings, histopathologic findings, and/or the Crohn disease activity index was the reference standard. Interobserver agreement between the two readers was calculated with κ statistics. Associations between CT enteroclysis findings and anastomotic site status were assessed at univariate analysis. The sensitivity, specificity, and accuracy of CT enteroclysis, with corresponding 95% confidence intervals (CIs), for the diagnosis of normal versus abnormal anastomosis and the diagnosis of anastomotic recurrence versus fibrostenosis were estimated. Results Interobserver agreement regarding CT enteroclysis criteria was good to perfect (κ = 0.72–1.00). At univariate analysis, stratification and anastomotic wall thickening were the two most discriminating variables in the differentiation between normal and abnormal anastomoses (P < .001). Stratification (P < .001) and the comb sign (P = .026) were the two most discriminating variables in the differentiation between anastomotic recurrence and fibrostenosis. In the diagnosis of anastomotic recurrence, severe anastomotic stenosis was the most sensitive finding (95% [20 of 21 patients]; 95% CI: 76.18%, 99.88%), both comb sign and stratification had 95% specificity (18 of 19 patients; 95% CI: 73.97%, 99.87%), and stratification was the most accurate finding (92% [37 of 40 patients]; 95% CI: 79.61%, 98.43%). In the diagnosis of fibrostenosis, both severe anastomotic stenosis and anastomotic wall thickening were 100% sensitive (eight of eight patients; 95% CI: 63.06%, 100.00%), and using an association among five categorical variables, including severe anastomotic stenosis, anastomotic wall thickening with normal or mild mucosal enhancement, absence of comb sign, and absence of fistula, yielded 88% sensitivity (seven of eight patients; 95% CI: 47.35%, 99.68%), 97% specificity (31 of 32 patients; 95% CI: 83.78%, 99.92%), and 95% accuracy (38 of 40 patients; 95% CI: 83.08%, 99.39%). Conclusion CT enteroclysis yields objective and relatively specific morphologic criteria that help differentiate between recurrent disease and fibrostenosis at the anastomotic site after ileocolic resection for Crohn disease. © RSNA, 2010 Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.09091165/-/DC1

To evaluate the role, efficacy and safety of pelvic embolization in the management of severe postpartum hemorrhage in women with placenta accreta, increta or percreta.The clinical files and angiographic examinations of 12 consecutive women with placenta accreta (n=4), increta (n=2) or percreta (n=6) who were treated with pelvic embolization because of severe primary (n=10) or secondary (n=2) postpartum hemorrhage were reviewed. Before embolization, four women had complete placental conservation, four had partial placental conservation, three had an extirpative approach and one had hysterectomy after failed partial conservative approach.In 10 women, pelvic embolization was successful and stopped the bleeding, after one (n=7) or two sessions (n=3). Emergency hysterectomy was needed in two women with persistent bleeding after embolization, both with placenta percreta and bladder involvement first treated by extirpation. One case of regressive hematoma at the puncture site was the single complication of embolization.In women with severe postpartum hemorrhage due to placenta accreta, increta or percreta, pelvic embolization is effective for stopping the bleeding in most cases, thus allowing uterine conservation and future fertility. Further studies, however, should be done to evaluate the potential of pelvic embolization in women with placenta percreta with bladder involvement.

Purpose The purpose of this study was to retrospectively compare the respective sensitivities of diffusion-weighted (DW), T2-weighted fast spin-echo (T2WFSE) and gadolinium chelate-enhanced MR imaging in the preoperative detection of hepatic metastases using intraoperative ultrasonographic and histopathologic findings as the standard of reference. Materials and methods Twenty-seven patients with 64 surgically and histopathologically proven hepatic metastases had MR imaging of the liver, including DW, T2WFSE and dynamic gadolinium chelate-enhanced MR imaging. Images from each MR sequence were separately analyzed by two readers with disagreements resolved by consensus readings. The findings on MR images were compared with intraoperative ultrasonographic and histopathologic findings on a lesion-by-lesion basis to determine the sensitivity of each MR sequence. Statistical review of the lesion-by-lesion analysis was performed with the McNemar test. Results DW, T2WFSE and gadolinium chelate-enhanced MR imaging allowed the depiction of 54/64 (84.4%; 95% CI: 73.1–92.2%), 44/64 (68.8%; 95% CI: 55.9–79.8%), and 51/64 (79.7%; 95% CI: 67.8–88.7%) hepatic metastases respectively. DW MR images allowed depiction of significantly more hepatic metastases than did T2WFSE and was equivalent to gadolinium chelate-enhanced MR imaging (P = .002 and P = .375, respectively). Conclusion DW MR imaging is superior to T2WFSE imaging and equivalent to gadolinium chelate-enhanced MR imaging for the preoperative detection of hepatic metastases. Further studies however are needed to determine at what extent DW MR imaging can be used as an alternative to gadolinium chelate-enhanced MR imaging for the preoperative depiction of hepatic metastases.

Purpose To investigate the safety of gadoterate meglumine and identify the incidence of nephrogenic systemic fibrosis (NSF). Materials and Methods An international prospective observational study was conducted from November 2008 to June 2013. A total of 35,499 adults and children who were scheduled to undergo contrast‐enhanced MRI using gadoterate meglumine were analyzed (female, 53.1%; mean age: 49.5 years; range: 0‐98 years). At least 3‐month follow‐up was planned for patients with an estimated creatinine clearance or glomerular filtration rate &lt;60 mL/min (/1.73 m2) to detect any suspicion or occurrence of NSF. Adverse events (AEs) were prospectively recorded. Demographic data, risk factors, indications for MRI examinations, characteristics of gadoterate meglumine administration, and efficacy were documented. Results MRI examinations were mainly for central nervous system (61%). The most frequent risk factor was renal insufficiency (14.7%). Seventy AEs were observed in 44 patients (0.12%). Among the 70 AEs, 38 in 32 patients (0.09% of all patients) were considered related to gadoterate meglumine and classified as adverse drug reaction (ADR).The most frequent ADRs were urticaria (9 patients, 0.03%), nausea (7 patients, 0.02%), and vomiting (4 patients, 0.01%). Within the pediatric population (1,629 patients), only one AE (vomiting) was observed. Nine adult patients (0.03%) experienced serious AEs. Moderate to severe renal insufficiency at inclusion was reported in 514 patients (1.5%). Among them, 476 (92.6%) were followed‐up. No patients were suspected of having NSF and no cases of NSF were observed. Conclusion Our study confirms the excellent safety profile of gadoterate meglumine in routine practice. Level of Evidence: 1 J. Magn. Reson. Imaging 2017;45:988–997

Inflammatory bowel diseases (IBD) are associated with an increased risk of gastrointestinal cancers depending on the specific type of IBD, the extent of the disease and its location. Patients with IBD and extensive colonic involvement are at increased risk of colorectal cancer whereas patients with Crohn disease have an increased risk for small-bowel and anal carcinoma. These cancers preferentially develop on sites of longstanding inflammation. In regards to colon cancer, several key pathogenic events are involved, including chromosomal instability, microsatellite instability and hypermethylation. The risk for colon cancer in IBD patients correlates with longer disease duration, presence of sclerosing cholangitis, pancolitis, family history of colorectal cancer, early onset of the disease and severity of bowel inflammation. Identification of increased colorectal cancer risk in individual IBD patients has led to formal surveillance guidelines. Conversely, although an increased risk for other types of cancer has been well identified, no specific formal screening recommendations exist. Consequently, the role of the radiologist is crucial to alert the referring gastroenterologist when a patient with IBD presents with unusual imaging findings at either computed tomography (CT) or magnetic resonance (MR) imaging. This review provides an update on demographics, molecular, clinical and histopathological features of gastrointestinal cancers in IBD patients including colorectal carcinoma, small bowel adenocarcinoma, neuroendocrine tumors and anal carcinoma, along with a special emphasis on the current role of CT and MR imaging.

Peutz-Jeghers syndrome (PJS) is a rare, autosomal dominant disease linked to a mutation of the STK 11 gene and is characterized by the development of benign hamartomatous polyps in the gastrointestinal tract in association with a hyperpigmentation on the lips and oral mucosa. Patients affected by PJS have an increased risk of developing gastrointestinal and extra-digestive cancer. Malignancy most commonly occurs in the small-bowel. Extra-intestinal malignancies are mostly breast cancer and gynecological tumors or, to a lesser extent, pancreatic cancer. These polyps are also at risk of acute gastrointestinal bleeding, intussusception and bowel obstruction. Recent guidelines recommend regular small-bowel surveillance to reduce these risks associated with PJS. Small-bowel surveillance allows for the detection of large polyps and the further referral of selected PJS patients for endoscopic enteroscopy or surgery. Video capsule endoscopy, double balloon pushed enteroscopy, multidetector computed tomography and magnetic resonance enteroclysis or enterography, all of which are relatively new techniques, have an important role in the management of patients suffering from PJS. This review illustrates the pathological, clinical and imaging features of small-bowel abnormalities as well as the role and performance of the most recent imaging modalities for the detection and follow-up of PJS patients.

Detection and characterization of adrenal lesions have evolved during the past two decades. Although the role of imaging in adrenal lesions associated with hormonal secretion is usually straightforward, characterization of non-functioning adrenal lesions may be challenging to confidently identify those that need to be resected. Although many adrenal lesions can be readily diagnosed when they display typical imaging features, the diagnosis may be challenging for atypical lesions. Computed tomography (CT) remains the cornerstone of adrenal imaging, but other morphological or functional modalities can be used in combination to reach a diagnosis and avoid useless biopsy or surgery. Early- and delayed-phase contrast-enhanced CT images are essential for diagnosing lipid-poor adenoma. Ongoing studies are evaluating the capabilities of dual-energy CT to provide valid virtual non-contrast attenuation and iodine density measurements from contrast-enhanced examinations. Adrenal lesions with attenuation values between 10 and 30 Hounsfield units (HU) on unenhanced CT can be characterized by MRI when iodinated contrast material injection cannot be performed. 18F-FDG PET/CT helps differentiate between atypical benign and malignant adrenal lesions, with the adrenal-to-liver maximum standardized uptake value ratio being the most discriminative variable. Recent studies evaluating the capabilities of radiomics and artificial intelligence have shown encouraging results.

Artificial intelligence has demonstrated utility and is increasingly being used in the field of radiology. The use of generative pre-trained transformer (GPT)-based models has the potential to revolutionize the field of radiology, offering new possibilities for improving accuracy, efficiency, and patient outcome. Current applications of GPT-based models in radiology include report generation, educational support, clinical decision support, patient communication, and data analysis. As these models continue to advance and improve, it is likely that more innovative uses for GPT-based models in the field of radiology at large will be developed, further enhancing the role of technology in the diagnostic process. ChatGPT is a variant of GPT that is specifically fine-tuned for conversational language understanding and generation. This article reports some answers provided by ChatGPT to various questions that radiologists may have regarding ChatGPT and identifies the potential benefits ChatGPT may offer in their daily practice but also current limitations. Similar to other applications of artificial intelligence in the field of imaging, further formal validation of ChatGPT is required.

The purpose of this study was to investigate the impact of deep learning accelerated diffusion-weighted imaging (DWIDL) in 1.5-T liver MRI on image quality, sharpness, and diagnostic confidence.One-hundred patients who underwent liver MRI at 1.5-T including DWI with two different b-values (50 and 800 s/mm²) between February and April 2022 were retrospectively included. There were 54 men and 46 women, with a mean age of 59 ± 14 (SD) years (range: 21–88 years). The single average raw data were retrospectively processed using a deep learning (DL) image reconstruction algorithm leading to a simulated acquisition time of 1 min 28 s for DWIDL as compared to 2 min 31 s for standard DWI (DWIStd) via reduction of signal averages. All DWI datasets were reviewed by four radiologists using a Likert scale ranging from 1–4 using the following criteria: noise level, extent of artifacts, sharpness, overall image quality, and diagnostic confidence. Furthermore, quantitative assessment of noise and signal-to-noise ratio (SNR) was performed via regions of interest.No significant differences were found regarding artifacts and overall image quality (P > 0.05). Noise measurements for the spleen, liver, and erector spinae muscles revealed significantly lower noise for DWIDL versus DWIStd (P < 0.001). SNR measurements in the above-mentioned tissues also showed significantly superior results for DWIDL versus DWIStd for b = 50 s/mm² and ADC maps (all P < 0.001). For b = 800 s/mm², significantly superior results were found for the spleen, right hemiliver, and erector spinae muscles.DL image reconstruction of liver DWI at 1.5-T is feasible including significant reduction of acquisition time without compromised image quality.

The adrenal gland is home to an array of complex physiological and neoplastic disease processes. While dedicated adrenal computed tomography (CT) is the gold standard imaging modality for adrenal lesions, there exists significant overlap among imaging features of adrenal pathology. This can often make radiological diagnosis and subsequent determination of the optimal surgical approach challenging. Cinematic rendering (CR) is a novel CT post-processing technique that utilizes advanced light modeling to generate highly photorealistic anatomic visualization. This generates unique prospects in the evaluation of adrenal masses. As one of the first large tertiary care centers to incorporate CR into routine diagnostic workup, our preliminary experience with using CR has been positive, and we have found CR to be a valuable adjunct during surgical planning. Herein, we highlight the unique utility of CR techniques in the workup of adrenal lesions and provide commentary on the opportunities and obstacles associated with the application of this novel display method in this setting.

Interventional Oncology (IO) stands at the forefront of transformative cancer care, leveraging advanced imaging technologies and innovative interventions. This narrative review explores recent developments within IO, highlighting its potential impact facilitated by artificial intelligence (AI), personalized medicine and imaging innovations. The integration of AI in IO holds promise for accelerating tumour detection and characterization, guiding treatment strategies and refining predictive models. Imaging modalities, including functional MRI, PET and cone beam CT are reshaping imaging and precision. Navigation, fusion imaging, augmented reality and robotics have the potential to revolutionize procedural guidance and offer unparalleled accuracy. New developments are observed in embolization and ablative therapies. The pivotal role of genomics in treatment planning, targeted therapies and biomarkers for treatment response prediction underscore the personalization of IO. Quality of life assessment, minimizing side effects and long-term survivorship care emphasize patient-centred outcomes after IO treatment. The evolving landscape of IO training programs, simulation technologies and workforce competence ensures the field's adaptability. Despite barriers to adoption, synergy between interventional radiologists' proficiency and technological advancements hold promise in cancer care.

To define the advantages and disadvantages of various rendering techniques to obtain three-dimensional (3D) displays of intrahepatic venous structures with helical CT data.After rapid preprocessing segmentation of the liver, helical CT data (8 mm slice thickness overlapped every 4 mm) from 10 patients were reconstructed using maximum intensity projection (MIP), volume rendering, and surface rendering algorithms. Three-dimensional imaging was evaluated blindly and independently by three observers for presence of artifacts and overall quality.Three-dimensional displays showed the hepatic veins and fifth order portal branches with the volume and MIP rendering techniques. Best overall quality in the 3D representation of the liver was achieved with the MIP technique (p < 0.05). Small details in venous anatomy and portal involvement by tumor were better imaged with the MIP technique. "Stair-step" artifacts markedly degraded the 3D displays obtained with the surface rendering technique, making it inappropriate for imaging the intrahepatic venous structures.Maximum intensity projection appears to be an adequate technique to perform 3D imaging of intrahepatic venous structures with helical CT data when 8 mm slice thicknesses overlapping every 4 mm are used. However, optimization of imaging protocols needs to be done and compared in a larger series.

The pancreas is located deep within the retroperitoneum in the anterior pararenal space. The distal portion of the pancreatic tail extends along the course of the splenic artery and vein (Fig. 1) and enters the splenic hilum contained within the splenorenal ligament. Because of these anatomic relationships, the spleen and splenic vessels may be involved by pancreatitis. Although rare (frequency, 1-5%), splenic involvement by pancreatitis includes intrasplenic pseudocyst, abscess, hemorrhage, infarction, splenic rupture, and vascular injury. Because these complications can be life-threatening, the extent and course of the disease are closely monitored with CT to determine whether and when aggressive intervention is necessary to avoid catastrophic clinical outcomes. The purpose of this essay is to illustrate the spectrum of CT findings in cases of pancreatitis with splenic involvement.

Percutaneous drainage (PD) of complex postoperative abscesses associated with a variety of factors such as multiple location or enteric fistula remains a matter of debate. Accordingly, this retrospective study was designed to determine the predictive factors for failure of PD of postoperative abscess, in order to better select the patients who may benefit from PD.From 1992 to 2000, the data of 73 patients who underwent computed tomography (CT)-guided PD for postoperative intra-abdominal abscess, were reviewed. PD was considered as failure when clinical sepsis persisted or subsequent surgery was needed. The possible association between failure of PD and 27 patient-, abscess-, surgical-, and drainage-related variables were assessed using univariate and multivariate analysis.Successful PD was achieved in 59 of 73 (81%) patients. The overall mortality was 3% but no patient died after salvage surgery. Multivariate analysis showed that only an abscess diameter of less than 5 cm (P = 0.042) and absence of antibiotic therapy (P = 0.01) were significant predictive variables for failure of PD.CT-guided PD associated with antibiotic therapy could be attempted as the initial treatment of postoperative abdominal abscesses even in complex cases such as loculated abscess or abscess associated with enteric fistula.

A prospective study was performed to compare, with a lesion-by-lesion analysis, the sensitivities of high field strength MRI and CT during arterial portography (CTAP) in detecting hepatic metastases from colorectal cancer. Twenty-one patients with liver metastases from colorectal cancer were prospectively investigated by high field strength MRI (1.5 or 2 T) and CTAP. High field strength MRI was performed with pre and post gadopentetate dimeglumine enhanced T1-weighted SE sequences and T2-weighted SE sequences. All patients underwent partial hepatectomy and 37 metastases were surgically and pathologically proved. The metastasis detection rate (sensitivity) was 94% (35 of 37) for CTAP and 78% (29 of 37) for high field strength MRI. The 16% (95% confidence interval: 1–31%) difference in sensitivity between CTAP and high field strength MRI was statistically significant (p < 0.05, Mc-Nemar test). The use of gadopentetate dimeglumine did not improve the sensitivity of T1-weighted SE sequences. Since our study demonstrated significant difference in sensitivities between high field strength MRI and CTAP in our group of patients, we can conclude that high field strength MRI cannot replace CTAP in the preoperative evaluation of patients with liver metastases from colorectal cancer. Computed tomography during arterial portography must be considered as the preoperative gold standard. Index Terms: Liver, neoplasms—Portography—Magnetic resonance imaging, techniques.

A wide range of nontumorous hepatic diseases may have an impact on liver function and serve as indications for computed tomographic (CT) or magnetic resonance (MR) imaging. New imaging techniques such as spiral CT and fast MR imaging aid in detecting and characterizing these disease processes and in assessing the extent of disease. Infectious liver disease (eg, hepatic abscess, echinococcal disease, fungal infection) typically has low attenuation at CT and high signal intensity at T2-weighted MR imaging. Cholangitis is characterized by ductal dilatation at both CT and MR imaging. In acute portal vein thrombosis, the thrombus has low attenuation at CT and is hyperintense relative to liver at MR imaging. Hepatic infarcts usually appear as well-circumscribed, peripheral, wedge-shaped areas of decreased attenuation at CT. The causes or complications of cirrhosis can be most readily identified with MR imaging. In patients with chronic radiation-induced hepatitis, CT shows the irradiated parenchyma as a region of increased attenuation, whereas T1- and T2-weighted MR imaging demonstrate geographic areas of low and high signal intensity, respectively. Hemachromatosis has homogeneously increased liver attenuation at CT and decreased signal intensity at gradient-echo MR imaging in particular. Familiarity with the CT and MR imaging features of the spectrum of nonneoplastic conditions of the liver is essential in making an accurate diagnosis.

To determine the sensitivity and false-positive rate of helical computed tomography during arterial portography (CTAP) in the detection of hepatic metastases from colorectal cancer.Preoperative helical CTAP was performed to examine 23 patients (10 men and 13 women, aged 43-77 years [mean, 63 years]) who later underwent surgical tumor resection. Imaging findings were retrospectively reviewed by two radiologists and were correlated with intraoperative and histologic findings.Helical CTAP demonstrated 33 of 35 metastases, with diameters of 4-95 mm, that were identified in resected specimens (sensitivity, 94%). The two metastases not demonstrated were 4 and 5 mm in diameter. Five false-positive lesions were found in four patients, yielding a false-positive rate of 17% by patient analysis and 13% by lesion analysis.The sensitivity of helical CTAP in the preoperative detection of hepatic metastases is high, and its false-positive rate compares favorably with that of conventional CTAP, but future comparative studies are needed to determine which is the better modality.

To compare the computed tomographic (CT) features of pancreatic fatty replacement in adolescents and adults with cystic fibrosis (CF) with those in control subjects and to correlate the degree of fatty replacement with the functional status of the pancreas.CT scans in 15 patients with CF (group 1) and in 15 control subjects without CF (group 2) were evaluated for thickness and degree of pancreatic fatty replacement. Thickness was measured at four anatomic levels. The pattern of pancreatic fatty replacement was visually evaluated in four pancreatic regions. Images were semiquantitatively analyzed by two readers. The degree of fatty replacement was correlated with the functional status of the pancreas.In group 1, pancreatic glandular tissue was significantly thinner (P < .001) and the degree of fatty replacement was significantly greater in the four regions (P < .001) than those in group 2. In Group 1, no relationship was found between the degree of pancreatic fatty replacement and that of pancreatic endocrine dysfunction. A significant relationship was found between the degree of fatty replacement and that of pancreatic exocrine dysfunction (P < .001).In patients with CF, pancreatic glandular tissue is significantly reduced in size. Pancreatic fatty replacement is the most frequent pattern in older patients with CF and correlates with pancreatic exocrine dysfunction.

The three most common techniques for three-dimensional reconstruction are surface rendering, maximum-intensity projection (MIP), and volume rendering. Surface-rendering algorithms model objects as collections of geometric primitives that are displayed with surface shading. The MIP algorithm renders an image by selecting the voxel with the maximum intensity signal along a line extended from the viewer's eye through the data volume. Volume-rendering algorithms sum the weighted contributions of all voxels along the line. Each technique has advantages and shortcomings that must be considered during selection of one for a specific clinical problem and during interpretation of the resulting images. With surface rendering, sharp-edged, clear three-dimensional reconstruction can be completed on modest computer systems; however, overlapping structures cannot be visualized and artifacts are a problem. MIP is computationally a fast technique, but it does not allow depiction of overlapping structures, and its images are three-dimensionally ambiguous unless depth cues are provided. Both surface rendering and MIP use less than 10% of the image data. In contrast, volume rendering uses nearly all of the data, allows demonstration of overlapping structures, and engenders few artifacts, but it requires substantially more computer power than the other techniques.

To compare transesophageal echocardiography (TEE) and magnetic resonance (MR) imaging in the diagnosis of dissection of the thoracic aorta.Thirty-one consecutive patients with clinically suspected aortic dissection and 10 postoperative patients underwent transesophageal color Doppler echocardiography and MR imaging. Imaging results were compared at independent double-blind readings. Final diagnosis was obtained from consensual review of all corroborative studies.MR imaging depicted the intimal flap in 95% of aortic dissections; TEE, in 86% (P < .05). In surgical patients, the sensitivity of MR in detection of residual dissection was 100% versus 86% with TEE (P < .05). The inferior extent of the dissected lumen was seen only with MR imaging. False-positive results occurred in two cases with TEE and in one with MR imaging.MR imaging is superior to TEE in the evaluation and follow-up of dissection of the thoracic aorta. Because the availability of MR is limited, however, TEE should remain the standard modality for diagnosis.

We retrospectively reviewed the dynamic CT examinations of eight patients with pancreatic lymphoma. Four tumors were rounded masses with well-defined contours, four were more infiltrating lesions. The median cross-sectional diameter of the tumors was 6 cm (range 2.5–12 cm). At dynamic CT, the tumors were hypodense (n = 8) and somewhat heterogeneous (n = 6). Additional features were enlarged lymph nodes, 1–3 cm in diameter (n = 5), dilatation of the biliary tract and pancreatic duct (n = 5), abnormalities in the fat around the celiac trunk and/or the superior mesenteric artery (n = 4), and venous stenosis or occlusion (n = 7). The CT findings of pancreatic lymphoma are more various than has been previously reported. Findings such as small tumor size, well-defined contours, tumor heterogeneity, pancreatic duct dilatation, and venous invasion may be seen. Pancreatic lymphoma cannot be reliably distinguished from pancreatic carcinoma by CT findings alone.

This article describes the recent advances in radiological imaging of malignant neoplasms of the mesenteric small bowel and provides an outline of new trends and perspectives that can be anticipated. The introduction of multidetector row technology, which allows the acquisition of submillimeter and isotropic voxels, has dramatically improved the capabilities of computed tomography in the investigation of the mesenteric small bowel. This technology combined with optimal filling of small bowel loops through the use of appropriate enteral contrast agents has markedly changed small bowel imaging. Computed tomography-enteroclysis, which is based on direct infusion of enteral contrast agent into the mesenteric small bowel through a naso-jejunal tube, provides optimal luminal distension. By contrast, computed tomography-enterography is based on oral administration of enteral contrast agent. These two techniques are now well-established ones for the detection and the characterization of small bowel neoplasms. During the same time, combining the advantages of unsurpassed soft tissue contrast and lack of ionizing radiation, magnetic resonance imaging has gained wide acceptance for the evaluation of patients with suspected small bowel neoplasms. Rapid magnetic resonance imaging sequences used in combination with specific enteral contrast agents generate superb images of the mesenteric small bowel so that magnetic resonance-enteroclysis and magnetic resonance-enterography are now considered as effective diagnostic tools for both the detection and the characterization of neoplasms of the mesenteric small bowel. Recent improvements in image post-processing capabilities help obtain realistic three-dimensional representations of tumors and virtual enteroscopic views of the small bowel that are useful for the surgeon and the gastroenteroenteologist to plan surgical or endoscopic interventions. Along with a better knowledge of the potential and limitations of wireless capsule endoscopy and new endoscopic techniques, these recent developments in radiological imaging reasonably suggest that substantial changes in the investigation of small bowel tumors may be anticipated in a near future, thus potentially create a new paradigm shift after standard small bowel follow-through study has been universally abandoned.

The purpose of this study was to retrospectively evaluate the incidence of intraperitoneal bleeding and other major complications of transjugular liver biopsy (TJLB) and analyze their outcome and management. The clinical files of 341 consecutive patients who had TJLB were retrospectively analyzed. There were 237 men and 104 women (mean age: 51.38 ± 12.8 years; range: 17–89 years). All patients had TJLB because standard percutaneous transhepatic biopsy was contraindicated. Patients’ files were reviewed to search for major and minor procedure-related complications during or immediately after TJLB. TJLBs were technically successful in 331/341 patients (97.07%; 95%CI: 94.67–98.58%). Major complications consisted exclusively of intraperitoneal bleeding due to liver capsule perforation and were observed in 2/341 patients (0.59%; 95%CI: 0.07–2.10%). They were treated using transcatheter arterial or venous embolization with a favorable outcome. The most frequent minor complications were abdominal pain (35/341; 10.26%; 95%CI: 7.25–13.99%) and supraventricular arrhythmia (15/341; 4.40%; 95%CI: 2.48–7.15%). No cases of inadvertent injury of the carotid artery were observed. Major complications during TJLB are extremely rare and can be managed using arterial or venous embolization with a favorable outcome. Our results reinforce the general assumption that TJLB is a safe and well-tolerated technique.

To qualitatively and quantitatively analyze the presentation of intrahepatic and hilar mass-forming cholangiocarcinoma with diffusion-weighted magnetic resonance imaging (DW-MRI).Twenty-eight patients with histopathologically proven mass-forming cholangiocarcinoma (hilar, n=17; intrahepatic, n=11) underwent hepatic DW-MRI at 1.5-T using free-breathing acquisition and three b-values (0,400,800s/mm(2)). Cholangiocarcinomas were evaluated qualitatively using visual analysis of DW-MR images and quantitatively with conventional ADC and normalized ADC measurements using liver and spleen as reference organs.All cholangiocarcinomas (28/28; 100%) were visible on DW-MR images. DW-MRI yielded best conspicuity of cholangiocarcinomas than the other MRI sequences (P<0.001). Seven cholangiocarcinomas (7/11; 64%) showed hypointense central area on DW-MR images. Conventional ADC value of cholangiocarcinomas (1.042×10(-3)mm(2)/s±0.221×10(-3)mm(2)/s; range: 0.616×10(-3)mm(2)/s to 2.050×10(-3)mm(2)/s) was significantly lower than that of apparently normal hepatic parenchyma (1.362×10(-3)mm(2)/s±0.187×10(-3)mm(2)/s) (P<0.0001), although substantial overlap was found. No significant differences in ADC and normalized ADC values were found between intrahepatic and hilar cholangiocarcinomas. The use of normalized ADC using the liver as reference organ resulted in the most restricted distribution of ADC values of cholangiocarcinomas (variation coefficient=16.6%).There is a trend towards a common appearance of intrahepatic and hilar mass-forming cholangiocarcinomas on DW-MRI but variations may be observed. Familiarity with these variations may improve the diagnosis of mass-forming cholangiocarcinoma.

Although a rare disease, anal cancer is increasingly being diagnosed in patients with risk factors, mainly anal infection with the human papilloma virus. Magnetic resonance imaging (MRI) with external phased-array coils is recommended as the imaging modality of choice to grade anal cancers and to evaluate the response assessment after chemoradiotherapy, with a high contrast and good anatomic resolution of the anal canal. MRI provides a performant evaluation of size, extent and signal characteristics of the anal tumor before and after treatment, as well as lymph node involvement and extension to the adjacent organs. MRI is also particularly helpful in the assessment of complications after treatment, and in the diagnosis for relapse of the diseases.

Fast scanning along with high resolution of multidetector computed tomography (MDCT) have expanded the role of non-invasive imaging of splanchnic arteries. Advancements in both MDCT scanner technology and three-dimensional (3D) imaging software provide a unique opportunity for non-invasive investigation of splanchnic arteries. Although standard axial computed tomography (CT) images allow identification of splanchnic arteries, visualization of small or distal branches is often limited. Similarly, a comprehensive assessment of the complex anatomy of splanchnic arteries is often beyond the reach of axial images. However, the submillimeter collimation that can be achieved with MDCT scanners now allows the acquisition of true isotropic data so that a high spatial resolution is now maintained in any imaging plane and in 3D mode. This ability to visualize the complex network of splanchnic arteries using 3D rendering and multiplanar reconstruction is of major importance for an optimal analysis in many situations. The purpose of this review is to discuss and illustrate the role of 3D MDCT angiography in the detection and assessment of abnormalities of splanchnic arteries as well as the limitations of the different reconstruction techniques.

Abnormally invasive placenta (AIP) is used to describe a placenta that does not separate naturally after delivery and cannot be extirpated without causing abnormally high blood loss. Recently, the use of a standardized terminology for descriptors of AIP signs seen on ultrasound has been prosed but to date no such unified descriptors have been developed for magnetic resonance imaging (MRI). The purpose of this paper is to propose a unified terminology based on a consensus opinion from the members of the International Society for AIP (IS-AIP) that include obstetricians, gynecologists, radiologists, pathologists, anesthesiologists and basic science researchers. We assume that using these standardized MRI descriptors for AIP will be useful for clinical use, education, teaching and future research projects, thus assumably improving care of patients with this condition. In addition, using a uniform terminology for AIP should become the first step of a standardized MRI report.

Interventional radiology plays an important role in the management of patients with neuroendocrine tumor liver metastasis (NELM). Transarterial embolization (TAE), transarterial chemoembolization (TACE), and selective internal radiation therapy (SIRT) are intra-arterial therapies available for these patients in order to improve symptoms and overall survival. These treatment options are proposed in patients with NELM not responding to systemic therapies and without extrahepatic progression. Currently, available data suggest that TAE should be preferred to TACE in patients with NELM from extrapancreatic origin because of similar efficacy and better patient tolerance. TACE is more effective in patients with pancreatic NELM and SIRT has shown promising results along with good tolerance. However, large randomized controlled trials are still lacking in this setting. Available literature mainly consists in small sample size and retrospective studies with important technical heterogeneity. The purpose of this review is to provide an updated overview of the currently reported endovascular interventional radiology procedures that are used for the treatment of NELM.

The purpose of this study was to determine whether texture analysis features on pretreatment contrast-enhanced computed tomography (CT) images and their evolution can predict treatment response of metastatic skin melanoma (SM) treated with anti-PD1 monoclonal antibodies.Sixty patients (29 men, 31 women; median age, 56 years; age range: 27-91 years) with metastatic SM treated with pembrolizumab (43/60; 72%) or nivolumab (17/60; 28%) were included. Texture analysis of SM metastases was performed on baseline and first post-treatment evaluation CT examinations. Mean gray-level, entropy, kurtosis, skewness, and standard deviation values were derived from the pixel distribution histogram before and after spatial filtration at different anatomic scales, ranging from fine to coarse. Lasso penalized Cox regression analyses were performed to identify independent variables associated with favorable response to treatment.A total of 127 metastases were analyzed, with a median of two metastases per patient. Skewness at fine texture scale (spatial scale filtration [SSF] = 2; Hazard ratio [HR]: 3.51; 95% CI: 2.08-8.57; P = 0.010), skewness at medium texture scale (SSF = 3; HR: 0.56; 95% CI: 0.11-1.59; P = 0.014), variation of entropy at fine texture scale (SSF = 2; HR: 37.76; 95% CI: 3.48-496.22; P = 0.008) and LDH above the threshold of 248 UI/L (HR: 3.56; 95% CI: 1.78-21.35; P = 0.032] were independent predictors of response to treatment.Pretreatment CT texture analysis-derived tumor skewness and variation of entropy between baseline and first control CT examination may be used as predictors of favorable response to anti-PD1 monoclonal antibodies in patients with metastatic SM.

To develop French guidelines by experts to standardize data acquisition, image interpretation, and reporting in rectal cancer staging with magnetic resonance imaging (MRI).Evidence-based data and opinions of experts of GRERCAR (Groupe de REcherche en Radiologie sur le CAncer du Rectum [i.e., Rectal Cancer Imaging Research Group]) and GRECCAR (Groupe de REcherche en Chirurgie sur le CAncer du Rectum [i.e., Rectal Cancer Surgery Research Group]) were combined using the RAND-UCLA Appropriateness Method to attain consensus guidelines. Experts scoring of reporting template and protocol for data acquisition were collected; responses were analyzed and classified as "Recommended" versus "Not recommended" (when ≥ 80% consensus among experts) or uncertain (when < 80% consensus among experts).Consensus regarding patient preparation, MRI sequences, staging and reporting was attained using the RAND-UCLA Appropriateness Method. A consensus was reached for each reporting template item among the experts. Tailored MRI protocol and standardized report were proposed.These consensus recommendations should be used as a guide for rectal cancer staging with MRI.

In 197 patients, uterine embolization with a single femoral approach and a single 5-F cobra catheter was successful in 362 of 394 (92%) uterine arteries. In six patients (12 arteries), distal embolization with a coaxial 3-F microcatheter was safer. In 10 patients with a life-threatening condition, embolization was performed at the anterior division of both internal iliac arteries. Bilateral selective embolization of the uterine arteries can be performed with a single catheter.

Low-attenuation defects in the liver that are caused by variations in the portal perfusion of the liver rather than by intrahepatic tumor can be detected using helical CT during arterial portography (CTAP). The purpose of this study was to characterize these nontumorous low-attenuation defects detected with helical CTAP in terms of their frequency, location, and appearance. Helical CTAP examinations of 89 patients referred for preoperative evaluation of metastatic or primary liver tumors performed over a 20-month period were retrospectively reviewed by three radiologists. The frequency, appearance, and location of focal (within a subsegment) and diffuse (affecting more than one subsegment) nontumorous perfusion defects were determined. Findings on helical CTAP images were correlated with surgical findings (53 patients), results of MR examinations (25 patients), and follow-up CT examinations (11 patients). Ninety-seven nontumorous perfusion defects were identified in 68 patients. The most frequent defects were located adjacent to the gallbladder fossa (35), anterior to the porta hepatis (34), in the subcapsular portion of the liver (13), and adjacent to the falciform ligament (12). Nontumorous perfusion defects characteristically appeared wedge-shaped or flat and ranged in size from 8-20 mm. Nontumorous perfusion abnormalities have characteristic appearances and locations on helical CTAP examinations and are more common than previously reported with conventional CTAP. Familiarity with the locations and characteristic appearances of these defects is essential to prevent false-positive diagnoses, so that operative candidates are not mistakenly denied surgical therapy.

A major use of imaging techniques in the preoperative evaluation of hepatic tumors is to help the surgeon determine the feasibility of hepatic resection. Although the segmental location of tumors is not the sole criterion for determining resectability, such information is crucial for the preoperative planning of the type of resection.

The purpose of this study was to compare breath-hold three-dimensional (3D) rapid gradient-echo (GRE) MR imaging obtained before and after gadolinium chelate injection with T2-weighted fast spin-echo and T2-weighted breath-hold fast spin-echo (BHFSE) MR imaging in the detection of focal hepatic masses.Fifty-three patients with 108 focal hepatic masses had, prospectively, MR of the liver at 1.5 T. T2-weighted fast spin-echo (6000/117 [TR/effective TE]; echo train length=16; acquisition time = 3 min 12 sec) images obtained with and without fat suppression, T2-weighted BHFSE (2700/105; echo train length = 20; acquisition time = 22 sec), and 3D rapid GRE images (10.1/1.9/30 degrees [TR/TE/alpha]) obtained during one breath-hold (12 scan locations in 21 sec or 20 scan locations in 32 sec) before and after injection of gadolinium chelate were blindly and independently analyzed in consensus by three readers.Gadolinium chelate-enhanced 3D rapid GRE images allowed depiction of more focal hepatic masses (90 of 108, sensitivity = 83%) than did T2-weighted fast spin-echo with fat suppression images (76 of 108, sensitivity = 70%), T2-weighted fast spin-echo without fat suppression images (74 of 108, sensitivity = 69%), T2-weighted BHFSE images (73 of 108, sensitivity = 68%), and unenhanced 3D rapid GRE images (54 of 108, sensitivity = 50%) (p < .01). No difference in sensitivity was found between the three T2-weighted sequences.Gadolinium chelate-enhanced 3D rapid GRE imaging is superior to T2-weighted fast spin-echo images obtained with or without fat suppression for the detection of focal hepatic masses. T2-weighted BHFSE is similar to T2-weighted fast spin-echo images in detecting focal hepatic lesions.

PURPOSE: To identify the reasons for the discrepancies between computed tomographic (CT) and pathologic staging of transitional cell carcinoma of the renal pelvis and to develop new criteria to increase the accuracy of CT in staging. MATERIALS AND METHODS: CT scans of 31 consecutive patients with renal pelvic transitional cell carcinoma were evaluated. CT and pathologic staging were compared. RESULTS: Pathologic staging revealed four stage 0 tumors, three stage I, five stage II, 10 stage III, and nine stage IV. The initial overall CT staging accuracy was 52% (16 of 31 patients). The sensitivity for minimal invasion was 17% (two of 12 patients). Two-thirds (10 of 15 patients) of the misinterpreted cases were overstaged as stage III. Proximal hydronephrosis was present in 80% of overstaged cases (eight of 10 patients). Reevaluation of the CT studies by using proximal hydronephrosis as a criterion for minimal invasion improved overall CT staging accuracy (77%). The revised staging yielded a sensitivity of 83% and specificity of 95% for minimal invasion and improved the specificity for deep invasion (17% to 92%). CONCLUSION: In a patient with transitional cell carcinoma of the renal pelvis, hydronephrosis proximal to the tumor may cause overstaging of stage 0-II disease and may not indicate more advanced disease.

The functional value of TurboFLASH MR imaging in the assessment of dynamic contrast enhancement and renal perfusion anomalies was evaluated in seven patients, who also underwent renal scintigraphy in baseline conditions. The basal renograms obtained from MAG-3 scintigraphy (mercapto acetyl triglycine, MAG3-S) and from Gd-DOTA-enhanced turboFLASH MRI were compared. After hydration, the protocol used consisted in breath-hold coronal turboFLASH acquisitions after IV bolus of Gd-DOTA (4 s every 20 s during 10 min) for MRI, and IV bolus of 370 MBq of 99mTc-MAG3 followed by 60 frames of 1 s and then 120 frames of 10 s for MAG3-S. Relative renal functions were computed for both methods by calculation of the integral of the uptake phase between the first and the second minute. Renograms exhibited 10 normal and 4 ischemic kidneys. There was a close correlation between the contrast enhancement of MRI and isotopic uptake in normal and ischemic kidneys. Global renograms of MRI correlated with MAG3-S (r=.82, p<.001) with similar curve shape and time to peak. Relative renal function of the right and left kidney were closely correlated in all patients (r=.98, p<.001), although there was a tendency for MR to overestimate MAG3-S evaluation in kidneys with severe basal dysfunction. Enhanced turboFLASH provides noninvasive assessment of renal perfusion in patients with renovascular disease. Accurate renograms are obtained with dynamic-enhanced MRI, but the relative renal function seems to be overestimated in low values of ischemic kidneys, and needs further comparative evaluation.

To compare dynamic contrast-enhanced subtraction (DCES) and T2-weighted spin-echo (SE) magnetic resonance (MR) imaging in the differentiation of fibrosis from recurrence during the follow-up of treated colorectal neoplasms.Forty-one patients with 39 malignant and 16 benign lesions confirmed by means of surgery (n = 23), biopsy (n = 24), or 12-month follow-up examination (n = 8) underwent DCES MR imaging and T2-weighted SE MR imaging. Enhancement of an abnormal pelvic structure within the first 90 seconds on DCES images or high signal intensity on T2-weighted SE images was considered indicative of malignancy.Sensitivity, specificity, and positive and negative predictive values were, respectively, 97%, 81%, 93%, and 100% for DCES MR imaging and 77%, 56%, 81%, and 56% for T2-weighted MR imaging. The number of correctly classified lesions was significantly higher with DCES imaging compared with T2-weighted imaging (P < or = .006).DCES imaging is more accurate than T2-weighted SE imaging for differentiating fibrosis from recurrence during the follow-up of treated colorectal neoplasms.

CT of hepatic tumors: prevalence and specificity of retraction of the adjacent liver capsule.P Soyer, D A Bluemke, C Vissuzaine, B V Beers, J Barge and M LevesqueAudio Available | Share

Pneumatosis intestinalis is a rare condition, which is defined by the presence of gas within the bowel wall. In adult patients, pneumatosis intestinalis can be depicted in various circumstances. Owing to the routine use of CT to investigate patients with abdominal pain, pneumatosis intestinalis can be seen as an incidental finding or can be observed in association with a life-threatening disease such as bowel infarction. On CT images, pneumatosis intestinalis can display two different appearances; one that has a cystic or bubbly appearance can be considered as a chronic pneumatosis and is suggestive for a benign cause while the other, which has a linear appearance can be considered as a symptom and is more frequently secondary to a life-threatening cause. However, none of these two CT characteristics can be considered pathognomonic for any of these two categories of causes. In such situations, the analysis of the location, extent and, if any, associated findings may help to differentiate between benign and life-threatening causes. In these patients who present with abdominal signs that mimic symptoms that would warrant surgical exploration, the analysis of associated findings is critical to rule out a life-threatening cause of pneumatosis intestinalis and to obviate the need for unnecessary laparotomy. In adult patients with a known specific disease such as celiac disease, chronic pseudointestinal obstruction or other chronic diseases, even with accompanying pneumoperitoneum, pneumatosis intestinalis does not uniformly mandate surgical exploration. This pictorial review presents the more and the less common pneumatosis intestinalis CT features in adult patients, with the aim of making the reader more familiar with this potentially misleading sign.

Our objective was to determine the diagnostic accuracy of a free-breathing diffusion-weighted single-shot echo-planar magnetic resonance imaging (FBDW-SSEPI) technique with parallel imaging and high diffusion factor value (b = 1000 s/mm2) in the detection of primary rectal adenocarcinomas. Thirty-one patients (14M and 17F; mean age 67 years) with histopathologically proven primary rectal adenocarcinomas and 31 patients without rectal malignancies (14M and 17F; mean age 63.6 years) were examined with FBDW-SSEPI (repetition time (TR/echo time (TE) 3900/91 ms, gradient strength 45 mT/m, acquisition time 2 min) at 1.5 T using generalized autocalibrating partially parallel acquisitions (GRAPPA, acceleration factor 2) and a b value of 1000 s/mm2. Apparent diffusion coefficients (ADCs) of rectal adenocarcinomas and normal rectal wall were measured. FBDW-SSEPI images were evaluated for tumour detection by 2 readers. Sensitivity, specificity, accuracy and Youden score for rectal adenocarcinoma detection were calculated with their 95% confidence intervals (CI) for ADC value measurement and visual image analysis. Rectal adenocarcinomas had significantly lower ADCs (mean 1.036 × 10−3 ± 0.107 × 10−3 mm2/s; median 1.015 × 10−3 mm2/s; range (0.827–1.239) × 10−3 mm2/s) compared with the rectal wall of control subjects (mean 1.387 × 10−3 ± 0.106 × 10−3 mm2/s; median 1.385 × 10−3 mm2/s; range (1.176–1.612) × 10−3 mm2/s) (p < 0.0001). Using a threshold value ≤ 1.240 × 10−3 mm2/s, all rectal adenocarcinomas were correctly categorized and 100% sensitivity (31/31; 95% CI 95–100%), 94% specificity (31/33; 95% CI 88–100%), 97% accuracy (60/62; 95% CI 92–100%) and Youden index 0.94 were obtained for the diagnosis of rectal adenocarcinoma. FBDW-SSEPI image analysis allowed depiction of all rectal adenocarcinomas but resulted in 2 false-positive findings, yielding 100% sensitivity (31/31; 95% CI 95–100%), 94% specificity (31/33; 95% CI 88–100%), 97% accuracy (60/62; 95% CI 92–100%) and Youden index 0.94 for the diagnosis of primary rectal adenocarcinoma. We can conclude that FBDW-SSEPI using parallel imaging and high b value may be helpful in the detection of primary rectal adenocarcinomas.

To describe the computed tomographic (CT) enteroclysis features of uncomplicated celiac disease (CD) and to determine the most indicative appearance of this condition by using a retrospective case-control study.This study had institutional review board approval. The CT enteroclysis examinations of 44 consecutive patients with proved uncomplicated CD (21 men, 23 women; mean age, 44.45 years) were reviewed by two blinded readers and compared with those obtained in 44 control subjects (21 men, 23 women; mean age, 44.48 years), who were matched for sex and age. Comparisons were calculated by using univariate analysis.Reversed jejunoileal fold pattern had the highest specificity (100%; 44 of 44; 95% confidence interval [CI]: 91.96%, 100%) and was the most discriminating independent variable for the diagnosis of uncomplicated CD (odds ratio, 39.9; P < .0001) but had a sensitivity of 63.64% (28 of 44; 95% CI: 47.77%, 77.59%). Ileal fold thickening, vascular engorgement, and splenic atrophy were other variables that strongly correlated with the presence of uncomplicated CD.CT enteroclysis may help establish a diagnosis of uncomplicated CD and may clarify the cause of nonspecific gastrointestinal symptoms in patients with unknown CD. However, future prospective trials are needed to determine the actual value of CT enteroclysis in patients with CD and validate the clinical usefulness of CT enteroclysis in the detection of unknown uncomplicated CD.

In cases of serious bleeding postpartum, resuscitation and surgical techniques are complementary and should be adapted to both the etiology and severity of bleeding. In extremely severe cases, the performance of a hysterectomy should not be delayed. For women with stable hemodynamic status, so-called "conservative" surgical techniques can instead be used. In this study, we describe and discuss the indications and feasibility of various techniques of vascular ligation. Uterine mattress suture compression techniques and abdomino-pelvic packing are also described. When conservative management is feasible, the first line approach should be bilateral distal ligation of the uterine arteries: this simple and low-risk technique is immediately effective in 80% of cases. If bleeding persists, uterine devascularization can be completed by a triple ligation as described by Tsirulnikov, with or without supplemental proximal ligation of the uterine arteries. This procedure should be performed in preference to the so-called "stepwise ligation sequence", which involves ligation of the ovarian pedicles and poses a risk of subsequent ovarian failure. Bilateral hypogastric artery ligation is also an effective and widely used first-line technique for experienced surgeons. This approach is technically challenging for less-experienced surgeons and is reserved for cases of failed triple ligation.

Purpose To determine the rate of negative appendectomy and clarify the causes of negative appendectomy in patients with clinically suspected acute appendicitis who had surgery after 64-section helical computed tomography (CT). Material and Methods A retrospective analysis of 1057 patients who had appendectomy after 64-section helical CT was performed to determine the rate of negative appendectomy. The 64-section helical CT examinations obtained with submillimeter and isotropic voxels in the patients with negative appendectomy were analyzed by two readers and compared to clinical, operative and histopathological reports, discharge summaries and original radiology reports. Results The negative appendectomy rate was 1.7% (18/1057). Appendix enlargement (>6 mm) and fat stranding were present in 17 (17/18; 94%) and 6 patients (6/18; 33%), respectively. In 13 patients (13/18; 72%) 64-section helical CT findings were consistent with acute appendicitis. Interpretive errors in original imaging reports were identified in five patients (5/18; 28%). Conclusion The preoperative use of 64-section helical CT results in a very low rate of negative appendectomy. Patients with negative appendectomy have 64-section helical CT findings consistent with a diagnosis of acute appendicitis in the majority of cases. Interpretive errors are less frequent.