Adherence to LI-RADS and EASL high-risk population criteria: A systematic review.

BACKGROUND AND AIMS: The Liver Imaging Reporting and Data System (LI-RADS) and European Association for the Study of the Liver (EASL) diagnostic criteria for noninvasive diagnosis of HCC can only be applied to patients at a high risk of HCC. This systematic review assesses adherence to the LI-RADS and EASL high-risk population criteria in published studies. APPROACH AND RESULTS: PubMed was searched for original research, published between January 2012 and December 2021, reporting LI-RADS and EASL diagnostic criteria on contrast-enhanced ultrasound, CT, or MRI. The algorithm version, publication year, risk status, and etiologies of chronic liver disease were recorded for each study. Adherence to high-risk population criteria was evaluated as optimal (unequivocal adherence), suboptimal (equivocal), or inadequate (clear violation). A total of 219 original studies were included, with 215 that used the LI-RADS criteria, 4 EASL only, and 15 that evaluated both LI-RADS and EASL criteria. Optimal, suboptimal, or inadequate adherence to high-risk population criteria was observed in 111/215 (51.6%), 86/215 (40.0%), and 18/215 (8.4%) LI-RADS and 6/19 (31.6%), 5/19 (26.3%), and 8/19 (42.1%) EASL studies ( p < 0.001) regardless of the imaging modality. Adherence to high-risk population criteria significantly improved according to the CT/MRI LI-RADS versions (optimal in v2018 in 64.5% of studies; v2017, 45.8%; v2014, 24.4%; v2013.1, 33.3%; p < 0.001) and the publication year (2020-2021, 62.5%; 2018-2019, 33.9%; 2014-2017, 39.3% of all LI-RADS studies; p = 0.002). No significant differences in adherence to high-risk population criteria were observed in the versions of contrast-enhanced ultrasound LI-RADS ( p = 0.388) or EASL ( p = 0.293). CONCLUSION: Adherence to high-risk population criteria was optimal or suboptimal in about 90% and 60% of LI-RADS and EASL studies, respectively.

Defining textbook outcome for selective internal radiation therapy of hepatocellular carcinoma: an international expert study.

BACKGROUND: A textbook outcome (TO) is a composite indicator covering the entire intervention process in order to reflect the "ideal" intervention and be a surrogate for patient important outcomes. Selective internal radiation therapy (SIRT) is a complex multidisciplinary and multistep intervention facing the challenge of standardization. This expert opinion-based study aimed to define a TO for SIRT of hepatocellular carcinoma. METHODS: This study involved two steps: (1) the steering committee (4 interventional radiologists) first developed an extensive list of possible relevant items reflecting an optimal SIRT intervention based on a literature review and (2) then conducted an international and multidisciplinary survey which resulted in the final TO. This survey was online, from February to July 2021, and consisted three consecutive rounds with predefined settings. Experts were identified by contacting senior authors of randomized trials, large observational studies, or studies on quality improvement in SIRT. This study was strictly academic. RESULTS: A total of 50 items were included in the first round of the survey. A total of 29/40 experts (73%) responded, including 23 interventional radiologists (79%), three nuclear medicine physicians (10%), two hepatologists, and one oncologist, from 11 countries spanning three continents. The final TO consisted 11 parameters across six domains ("pre-intervention workup," "tumor targeting and dosimetry," "intervention," "post-90Y imaging," "length of hospital stay," and "complications"). Of these, all but one were applied in the institutions of > 80% of experts. CONCLUSIONS: This multidimensional indicator is a comprehensive standardization tool, suitable for routine care, clinical round, and research.

Who publishes imaging articles in non-imaging journals? A large sample data-mining study.

OBJECTIVES: To assess the weight of imaging and imaging specialists (i.e., affiliated to a radiology/nuclear medicine department) in publications in non-imaging journals. METHODS: All articles indexed in English on the Embase database between 1989 and 2019 were extracted. The number and affiliation of authors were determined. A naive Bayesian classifier algorithm was trained to classify abstracts as "imaging" or "non-imaging." The main outcome was the number and position of imaging specialists in the authorship of imaging articles published in non-imaging journals. Analyses per medical specialties and per journal impact factor (IF) were performed. RESULTS: A total of 15,787,825 articles were included with 968,259 (6%) "imaging" articles. The proportion of imaging articles increased over time (+ 370%), quicker than the overall academic output. The proportion of imaging specialist among authors grew from 0.58% in 1989-1994 to 1.54% in 2015-2019. About 20% of imaging articles had ≥ 1 imaging specialist among authors. The proportion of imaging articles decreased with the IF (7.3% for IF 0-2.5 vs. 5.1% for IF > 10, p < 0.001), but the proportion of imaging specialist authors in imaging papers with ≥ 1 imaging specialist author increased with the IF (40% for IF 0-2.5, 53% for IF > 10, p < 0.001). There was significant variability across medical specialties. CONCLUSIONS: The weight of imaging articles and imaging specialist among authors in non-imaging journals has increased over time but remains limited. Most of the authors of imaging publications are not imaging specialists. Imaging specialists among authors in imaging papers are associated with a greater IF. KEY POINTS: • The proportion of imaging specialist authors in non-imaging journals, though small, has increased significantly. • Marked differences are observed according to medical specialties and the reputation/impact factor of the journal. • Collaboration between imaging specialists and non-specialists is associated with publication in higher impact journals.

Learning from the machine: AI assistance is not an effective learning tool for resident education in chest x-ray interpretation.

OBJECTIVES: To assess whether a computer-aided detection (CADe) system could serve as a learning tool for radiology residents in chest X-ray (CXR) interpretation. METHODS: Eight radiology residents were asked to interpret 500 CXRs for the detection of five abnormalities, namely pneumothorax, pleural effusion, alveolar syndrome, lung nodule, and mediastinal mass. After interpreting 150 CXRs, the residents were divided into 2 groups of equivalent performance and experience. Subsequently, group 1 interpreted 200 CXRs from the "intervention dataset" using a CADe as a second reader, while group 2 served as a control by interpreting the same CXRs without the use of CADe. Finally, the 2 groups interpreted another 150 CXRs without the use of CADe. The sensitivity, specificity, and accuracy before, during, and after the intervention were compared. RESULTS: Before the intervention, the median individual sensitivity, specificity, and accuracy of the eight radiology residents were 43% (range: 35-57%), 90% (range: 82-96%), and 81% (range: 76-84%), respectively. With the use of CADe, residents from group 1 had a significantly higher overall sensitivity (53% [n = 431/816] vs 43% [n = 349/816], p < 0.001), specificity (94% [i = 3206/3428] vs 90% [n = 3127/3477], p < 0.001), and accuracy (86% [n = 3637/4244] vs 81% [n = 3476/4293], p < 0.001), compared to the control group. After the intervention, there were no significant differences between group 1 and group 2 regarding the overall sensitivity (44% [n = 309/696] vs 46% [n = 317/696], p = 0.666), specificity (90% [n = 2294/2541] vs 90% [n = 2285/2542], p = 0.642), or accuracy (80% [n = 2603/3237] vs 80% [n = 2602/3238], p = 0.955). CONCLUSIONS: Although it improves radiology residents' performances for interpreting CXRs, a CADe system alone did not appear to be an effective learning tool and should not replace teaching. CLINICAL RELEVANCE STATEMENT: Although the use of artificial intelligence improves radiology residents' performance in chest X-rays interpretation, artificial intelligence cannot be used alone as a learning tool and should not replace dedicated teaching. KEY POINTS: • With CADe as a second reader, residents had a significantly higher sensitivity (53% vs 43%, p < 0.001), specificity (94% vs 90%, p < 0.001), and accuracy (86% vs 81%, p < 0.001), compared to residents without CADe. • After removing access to the CADe system, residents' sensitivity (44% vs 46%, p = 0.666), specificity (90% vs 90%, p = 0.642), and accuracy (80% vs 80%, p = 0.955) returned to that of the level for the group without CADe.

Completeness of reporting in abstracts of randomized controlled trials assessing interventional radiology for liver disease.

PURPOSE: To assess the completeness of reporting in abstracts of published randomized controlled trials (RCTs) assessing interventional radiology (IR) for liver disease; to assess whether publication of the 2017 CONSORT update for nonpharmacological treatments (NPT) resulted in changes in abstract reporting; and to identify factors associated with better reporting. MATERIAL AND METHODS: MEDLINE and Embase were searched to identify RCTs of IR for liver disease (January 2015-September 2020). Two reviewers assessed the completeness of abstract reporting according to the CONSORT-NPT-2017-update. The primary outcome was the mean number of CONSORT items completely reported among 10 items reported in <50% of the abstracts published in 2015. A time series analysis assessed the evolution trend over time. A multivariate regression model was used to identify factors associated with better reporting. RESULTS: A total of 107 abstracts of RCTs published in 61 journals were included. Overall, 74% (45/61) of journals endorsed the main CONSORT guidelines, of which 60% (27/45) had a policy to implement them. The mean number of primary outcome items completely reported increased by 0.19 over the study period. The publication of the CONSORT-NPT update did not lead to an increase in the trend of items reported (increase of 0.04 items/month before vs. 0.02 after, P=0.41). Factors associated with more complete reporting were impact factor (OR=1.13; 95%CI:1.07-1.18) and endorsement of CONSORT with an implementation policy (OR=8.29; 95%CI:2.04-33.65). CONCLUSION: Completeness of reporting is incomplete in abstracts of trials of IR liver disease and did not improve after publication of the CONSORT-NPT-2017 update with abstract guidance.

The Safety and Effectiveness of Hepatic Transarterial Embolic Locoregional Therapy in Patients with Contraindications to Hepatectomy after Portal Vein Embolization.

The safety and effectiveness of hepatic transarterial embolic locoregional therapy (LRT) was assessed, including transarterial chemoembolization (TACE) and transarterial radioembolization (TARE), in patients who underwent portal vein embolization (PVE) before major hepatectomy in whom surgery was then contraindicated. Adverse events (AEs) were graded according to the Society of Interventional Radiology classification of AEs. Tumor response was assessed based on the Response Evaluation Criteria In Solid Tumors 1.1. Overall survival (OS) and progression-free survival (PFS) were estimated. Fifteen patients underwent 37 transarterial LRTs (25 TACEs, 11 TAREs, and 1 bland embolization), most (73%) with hepatocellular carcinoma. Eleven AEs occurred in 7 patients, including 2 Grade 3/5 (severe) and 2 Grade 4/5 (life-threatening) events. The best response was partial response in 4 (27%) and stable disease in 10 (66%) patients. The median OS and PFS were 42 (95% CI, 35-49 months) and 33 months (95% CI, 24-42 months), respectively. In conclusion, hepatic transarterial LRT can be considered as a therapeutic option in patients with contraindicated liver surgery after PVE.

Liver surface nodularity on non-contrast MRI identifies advanced fibrosis in patients with NAFLD.

OBJECTIVES: To evaluate the diagnostic performance of liver surface nodularity (LSN) for the assessment of advanced fibrosis in patients with non-alcoholic fatty liver disease (NAFLD). METHODS: We retrospectively analysed patients with pathologically proven NAFLD who underwent liver MRI. Demographic, clinical, and laboratory data (including FIB-4 scores) were gathered. The SAF score was used to assess NAFLD. MRI-proton density fat fraction (PDFF) and LSN were determined on pre-contrast MR sequences. ROC curve analysis was performed to evaluate the diagnostic performance of MRI-LSN for the diagnosis of advanced (F3-F4) liver fibrosis. RESULTS: The final population included 142 patients. Sixty-seven (47%) patients had non-alcoholic steatohepatitis (NASH), and 52 (37%) had advanced fibrosis. The median MRI-PDFF increased with the grades of steatosis: 8.1%, 18.1%, and 31% in S1, S2, and S3 patients, respectively (p < 0.001). The area under the ROC curve (AUC) of MRI-LSN ≥ 2.50 was 0.838 (95%CI 0.767-0.894, sensitivity 67.3%, specificity 88.9%, positive and negative predictive values 77.8% and 82.5%, respectively) for the diagnosis of advanced fibrosis. Combining FIB-4 and MRI-LSN correctly classified 103/142 (73%) patients. This was validated in an external cohort of 75 patients. CONCLUSIONS: MRI-LSN has good diagnostic performance in diagnosis of advanced fibrosis in NAFLD patients. A combination of FIB-4 and MRI-LSN derived from pre-contrast MRI could be helpful to detect advanced fibrosis. KEY POINTS: • MRI-LSN ≥ 2.5 was accurate for the diagnosis of advanced hepatic fibrosis in NAFLD patients. • The combination of FIB-4 and MRI-LSN improved the detection of advanced fibrosis. • MRI-LSN can be easily derived by unenhanced MRI sequences that are routinely acquired.

MRI is useful to suggest and exclude malignancy in mucinous cystic neoplasms of the pancreas.

OBJECTIVES: To evaluate the value of MRI in differentiating benign (b-MCN) and malignant (m-MCN) MCN. European guidelines suggest that certain mucinous cystic neoplasms (MCN) of the pancreas can be conservatively managed. METHODS: A retrospective single-center study of consecutive patients with resected MCN. MRIs were independently reviewed by two readers blinded to the pathological results. The authors compared b-MCN (i.e., mucinous-cystadenoma comprising high-grade dysplasia (HGD)) and m-MCN (i.e., cystadenocarcinoma). RESULTS: Sixty-three patients (62 women [98%]) with 63 MCN (6 m-MCN, 2 HGD) were included. m-MCN tumors had a tendency to be larger than b-MCN (median 86 [25-103] vs. 45 [17-130] mm, p = .055). The combination of signal heterogeneity on T2-weighted imaging, wall thickness ≥ 5 mm, the presence of mural nodules ≥ 9 mm, and enhancing septa had an area under the ROC curve of 0.97 (95% CI 0.91-1.00) for the diagnosis of m-MCN. A total of 24 (37%), 20 (32%), 10 (16%), 5 (8%), and 4 (6%) out of 63 MCNs showed 0, 1, 2, 3, and 4 of these features, respectively. The corresponding rate of m-MCN was 0%, 0%, 10%, 20%, and 100%, respectively, with a good-to-excellent inter-reader agreement. Patterns with a high NPV for m-MCN included an absence of enhancing septa or walls (NPV 97% and 100%, respectively), wall thickness < 3 mm (NPV 100%), and no mural nodules (NPV 100%). CONCLUSIONS: A combination of 4 imaging features suggests malignant MCN on MRI. On the other hand, visualization of a thin non-enhancing wall with no mural nodules suggests benign MCN. KEY POINTS: • A heterogenous signal on T2-weighted MRI, a ≥ 5-mm-thick wall, mural nodules ≥ 9 mm, and/or enhancing septa suggest malignant MCNs. • A thin non-enhancing wall with no mural nodules suggests benign MCNs. • MRI should be performed in the pre-therapeutic evaluation of MCN to help determine the therapeutic strategy in these patients.

Study of Thoracic CT in COVID-19: The STOIC Project.

Background There are conflicting data regarding the diagnostic performance of chest CT for COVID-19 pneumonia. Disease extent at CT has been reported to influence prognosis. Purpose To create a large publicly available data set and assess the diagnostic and prognostic value of CT in COVID-19 pneumonia. Materials and Methods This multicenter, observational, retrospective cohort study involved 20 French university hospitals. Eligible patients presented at the emergency departments of the hospitals involved between March 1 and April 30th, 2020, and underwent both thoracic CT and reverse transcription-polymerase chain reaction (RT-PCR) testing for suspected COVID-19 pneumonia. CT images were read blinded to initial reports, RT-PCR, demographic characteristics, clinical symptoms, and outcome. Readers classified CT scans as either positive or negative for COVID-19 based on criteria published by the French Society of Radiology. Multivariable logistic regression was used to develop a model predicting severe outcome (intubation or death) at 1-month follow-up in patients positive for both RT-PCR and CT, using clinical and radiologic features. Results Among 10 930 patients screened for eligibility, 10 735 (median age, 65 years; interquartile range, 51-77 years; 6147 men) were included and 6448 (60%) had a positive RT-PCR result. With RT-PCR as reference, the sensitivity and specificity of CT were 80.2% (95% CI: 79.3, 81.2) and 79.7% (95% CI: 78.5, 80.9), respectively, with strong agreement between junior and senior radiologists (Gwet AC1 coefficient, 0.79). Of all the variables analyzed, the extent of pneumonia at CT (odds ratio, 3.25; 95% CI: 2.71, 3.89) was the best predictor of severe outcome at 1 month. A score based solely on clinical variables predicted a severe outcome with an area under the curve of 0.64 (95% CI: 0.62, 0.66), improving to 0.69 (95% CI: 0.6, 0.71) when it also included the extent of pneumonia and coronary calcium score at CT. Conclusion Using predefined criteria, CT reading is not influenced by reader's experience and helps predict the outcome at 1 month. ClinicalTrials.gov identifier: NCT04355507 Published under a CC BY 4.0 license. Online supplemental material is available for this article. See also the editorial by Rubin in this issue.

Efficacy of Chest CT for COVID-19 Pneumonia Diagnosis in France.

Background The role and performance of chest CT in the diagnosis of the coronavirus disease 2019 (COVID-19) pandemic remains under active investigation. Purpose To evaluate the French national experience using chest CT for COVID-19, results of chest CT and reverse transcription polymerase chain reaction (RT-PCR) assays were compared together and with the final discharge diagnosis used as the reference standard. Materials and Methods A structured CT scan survey (NCT04339686) was sent to 26 hospital radiology departments in France between March 2, 2020, and April 24, 2020. These dates correspond to the peak of the national COVID-19 epidemic. Radiology departments were selected to reflect the estimated geographic prevalence heterogeneities of the epidemic. All symptomatic patients suspected of having COVID-19 pneumonia who underwent both initial chest CT and at least one RT-PCR test within 48 hours were included. The final discharge diagnosis, based on multiparametric items, was recorded. Data for each center were prospectively collected and gathered each week. Test efficacy was determined by using the Mann-Whitney test, Student t test, χ2 test, and Pearson correlation coefficient. P < .05 indicated a significant difference. Results Twenty-six of 26 hospital radiology departments responded to the survey, with 7500 patients entered; 2652 did not have RT-PCR test results or had unknown or excess delay between the RT-PCR test and CT. After exclusions, 4824 patients (mean age, 64 years ± 19 [standard deviation], 2669 male) were included. With final diagnosis as the reference, 2564 of the 4824 patients had COVID-19 (53%). Sensitivity, specificity, negative predictive value, and positive predictive value of chest CT in the diagnosis of COVID-19 were 2319 of 2564 (90%; 95% CI: 89, 91), 2056 of 2260 (91%; 95% CI: 91, 92), 2056 of 2300 (89%; 95% CI: 87, 90), and 2319 of 2524 (92%; 95% CI: 91, 93), respectively. There was no significant difference for chest CT efficacy among the 26 geographically separate sites, each with varying amounts of disease prevalence. Conclusion Use of chest CT for the initial diagnosis and triage of patients suspected of having coronavirus disease 2019 was successful. © RSNA, 2021 Online supplemental material is available for this article.

HCC advances in diagnosis and prognosis: Digital and Imaging.

Hepatocellular carcinoma (HCC) is a major cause of cancer-related death worldwide. Understanding of the pathogenesis of HCC has significantly improved in the past few years due to advances in genetics, molecular biology and pathology. Several subtypes have been identified with different backgrounds and outcomes, leading to possible changes in disease management and challenging the role of imaging. Indeed, despite its pivotal role in the diagnostic workup, prognosis, and the decision-making process in patients with HCC, these recent developments are progressively redefining the role of imaging. First and most important, liver imaging is shifting from a purely qualitative to a quantitative paradigm, integrating quantitative imaging and radiomics in a digital era. Second, to improve patient management, imaging has gradually moved beyond tumor-centered assessment to include a broader evaluation of the liver and its function. This review describes and discusses these advances in the imaging for the diagnosis and prognosis of HCC.

Top 10 Reviewer Critiques of Radiology Artificial Intelligence (AI) Articles: Qualitative Thematic Analysis of Reviewer Critiques of Machine Learning/Deep Learning Manuscripts Submitted to JMRI.

BACKGROUND: Classical machine learning (ML) and deep learning (DL) articles have rapidly captured the attention of the radiology research community and comprise an increasing proportion of articles submitted to JMRI, of variable reporting and methodological quality. PURPOSE: To identify the most frequent reviewer critiques of classical ML and DL articles submitted to JMRI. STUDY TYPE: Qualitative thematic analysis. POPULATION: In all, 1396 manuscript journal articles submitted to JMRI for consideration in 2018, with thematic analysis performed of reviewer critiques of 38 artificial intelligence (AI) articles, comprised of 24 ML and 14 DL articles, from January 9, 2018 to June 2, 2018. FIELD STRENGTH/SEQUENCE: N/A. ASSESSMENT: After identifying and sampling ML and DL articles, and collecting all reviews, qualitative thematic analysis was performed to identify major and minor themes of reviewer critiques. STATISTICAL TESTS: Descriptive statistics provided of article characteristics, and thematic review of major and minor themes. RESULTS: Thirty-eight articles were sampled for thematic review: 24 (63.2%) focused on classical ML and 14 (36.8%) on DL. The overall acceptance rate of classical ML/DL articles was 28.9%, similar to the overall 2017-2019 acceptance rate of 23.1-28.1%. These articles resulted in 72 reviews analyzed, yielding a total 713 critiques that underwent formal thematic analysis consensus encoding. Ten major themes of critiques were identified, with 1-Lack of Information as the most frequent, comprising 268 (37.6%) of all critiques. Frequent minor themes of critiques concerning ML/DL-specific recommendations included performing basic clinical statistics such as to ensure similarity of training and test groups (N = 26), emphasizing strong clinical Gold Standards for the basis of training labels (N = 19), and ensuring strong radiological relevance of the topic and task performed (N = 16). DATA CONCLUSION: Standardized reporting of ML and DL methods could help address nearly one-third of all reviewer critiques made. LEVEL OF EVIDENCE: 4 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2020;52:248-254.

Results of trials assessing transarterial chemoembolization for treating hepatocellular carcinoma are critically underreported.

OBJECTIVE: We aimed to evaluate to what extent the results of registered randomized controlled trials (RCTs) assessing transarterial chemoembolization (TACE) for treating hepatocellular carcinoma (HCC) are publicly available. METHODS: We searched the Cochrane Central Register of Controlled Trials, the International Clinical Trials Registry Platform, and primary registries for RCTs assessing TACE for treating HCC, registered between January 2008 and August 2018, that had exceeded their completion date by more than 1 year. We systematically searched PubMed, EMBASE, and Google Scholar for a publication as well as the registry for results. The main outcomes were the availability of results, and the time to the first availability of results (i.e., posted on the registry or published). Secondary outcomes were the proportion of results available at 12 and 36 months after completion. RESULTS: Among 67 identified RCTs, including a total target number to 11,599 participants, 26 had publicly available results (39%; i.e., 42% of total target number of participants). Results of 25 RCTs (37%) were published, with only 3 having results posted on the registry and 2 with both published and posted results. The median (Q1-Q3) time from completion to the first public availability of results was 18 months (11-29). The cumulative percentages of RCTs with results available were 10% (95% CI, 3-17%) and 29% (95% CI, 17-39%) at 12 and 36 months, respectively, after completion. CONCLUSIONS: Despite the ethical commitments and societal expectations for disclosure of results, the availability of results of RCTs on TACE for treating HCC is very limited. KEY POINTS: • Underreporting of trial results is a major cause of wasted medical research since inaccessible research results fail to help both patients and clinicians. • Transarterial chemoembolization (TACE) is the most common treatment for hepatocellular carcinoma (HCC) and has called for considerable research efforts. • Yet, almost two-thirds of randomized controlled trials assessing TACE for treating HCC did not yield any public results, either on the registry platform or in scientific journals.

COVID-19 impact assessment on the French radiological centers: a nationwide survey.

PURPOSE: To determine the impact of the COVID-19 on the CT activities in French radiological centers during the epidemic peak. MATERIALS AND METHODS: A cross-sectional prospective CT scan survey was conducted between March 16 and April 12, 2020, in accordance with the local IRB. Seven hundred nine radiology centers were invited to participate in a weekly online survey. Numbers of CT examinations related to COVID-19 including at least chest (CTcovid) and whole chest CT scan activities (CTchest) were recorded each week. A sub-analysis on French departments was performed during the 4 weeks of the study. The impact of the number of RT-PCRs (reverse transcriptase polymerase chain reactions) on the CT workflow was tested using two-sample t test and Pearson's test. RESULTS: Five hundred seventy-seven structures finally registered (78%) with mean response numbers of 336 ± 18.9 (323; 351). Mean CTchest activity per radiologic structure ranged from 75.8 ± 133 (0-1444) on week 12 to 99.3 ± 138.6 (0-1147) on week 13. Mean ratio of CTcovid on CTchest varied from 0.36 to 0.59 on week 12 and week 14 respectively. There was a significant relationship between the number of RT-PCR performed and the number of CTcovid (r = 0.73, p = 3.10-16) but no link with the number of positive RT-PCR results. CONCLUSION: In case of local high density COVID-19, CT workflow is strongly modified and redirected to the management of these specific patients. KEY POINTS: • Over the 4-week survey period, 117,686 chest CT (CTtotal) were performed among the responding centers, including 61,784 (52%) CT performed for COVID-19 (CTcovid). • Across the country, the ratio CTcovid/CTtotal varied from 0.36 to 0.59 and depended significantly on the local epidemic density (p = 0.003). • In clinical practice, in a context of growing epidemic, in France, chest CT was used as a surrogate to RT-PCR for patient triage.

Does Ipsilateral-Dependent Positioning During Percutaneous Lung Biopsy Decrease the Risk of Pneumothorax?

OBJECTIVE: The purpose of this study is to determine whether placing patients in an ipsilateral-dependent position during percutaneous CT-guided transthoracic biopsy reduces the pneumothorax rate. MATERIALS AND METHODS: Between July 2013 and August 2017, a total of 516 patients (317 men and 199 women; mean age, 66.4 years) underwent core needle biopsies performed using 17- and 18-gauge needles. The overall pneumothorax rate and the rate of pneumothorax requiring drainage catheter insertion were compared between group A (patients placed in an ipsilateral-dependent position) and group B (patients placed in a position other than the ipsilateral-dependent position), with use of a chi-square test or Fisher exact test, as appropriate. Linear regression analysis and multiple regression analysis were performed for risk factors of pneumothorax, including patient characteristics (e.g., emphysema along the needle track), lesion characteristics (e.g., size and position), and biopsy technique characteristics (e.g., needle path length, needle-pleura angle, and fissure crossing). RESULTS: For patients in group A and group B, the overall pneumothorax rate (21/94 [22.3%] and 95/422 [22.5%], respectively; p = 0.97) and the rate of pneumothorax requiring drainage catheter insertion (6/94 [6.4%] and 28/422 [6.6%], respectively; p = 0.90) were not statistically different. After multiple regression analysis, the only independent risk factors for pneumothorax and insertion of a drainage catheter were needle path length (p < 0.001 and p = 0.02, respectively), emphysema along the needle track (p = 0.01 and p < 0.001, respectively), and fissure crossing (p = 0.04 and p < 0.001, respectively). CONCLUSION: Even though the pneumothorax rate does not appear to be reduced, with the limits of a retrospective evaluation considered, other advantages of the ipsilateral decubitus position exist, including protection of the contralateral lung in patients with severe hemoptysis.

The impact of the Paris terrorist attacks on the mental health of resident physicians.

BACKGROUND: On November 13, 2015, terrorist attacks took place in Paris. One hundred and twenty-nine people were immediately killed and 302 needed emergency care. Many resident physicians were on the front line of the medical response. Our aim was to report the frequency of symptoms of post-traumatic stress disorder (PTSD), anxiety and depression among resident physicians after the Paris terrorist attacks. METHODS: Anonymous questionnaires, including the Impact of Event Scale- Revised (IES-R) and the Hospital Anxiety and Depression Scale (HADS), were emailed two months after the attacks to 2413 Parisian resident physicians. Exposure to the attacks was defined as having direct clinical contact with one of the victims up to one week after the attacks, being one of the victims, or having one among close relatives. RESULTS: The questionnaire was completed by 680 (28.2%) residents. Eighty-four (12.4%) reported symptoms of PTSD (IES-R ≥ 33), 76 (11.2%) reported symptoms of anxiety (HADS anxiety score > 10) and 16 (2.4%) reported symptoms of depression (HADS depression score > 10). Exposed residents had higher IES-R scores than non-exposed residents (18.8 ± 16.6 versus 14.2 ± 12.0, p = 0.001), and 40 (18.5%) of them reported symptoms of PTSD, compared to 44 (9.5%) of the non-exposed residents (p = 0.001). CONCLUSIONS: There was a high frequency of symptoms of mental distress among our respondents. Dedicated screening and care strategies must be considered in the event of new attacks.

MR diagnosis of diaphragmatic endometriosis.

PURPOSE: To evaluate magnetic resonance imaging (MRI) for diaphragmatic endometriosis diagnosis. MATERIALS AND METHODS: Over a 2-year period, all diaphragmatic MRI performed in the context of diaphragmatic endometriosis were reviewed. Axial and coronal fat-suppressed T1- and T2-weighted sequences were analyzed by two independent readers for the presence of nodules, plaque lesions, micronodule clustering, or focal liver herniation. MR abnormalities were correlated to surgical findings in women surgically treated. Interobserver agreement was assessed by κ statistics. RESULTS: Twenty-three women with diaphragmatic endometriosis criteria comprised the population; 14 had surgical confirmation and nine had symptoms relief with hormonal treatment. MRI sensitivity was 83 % (19/23; 95 % confidence interval [CI]: 68, 98) for reader 1 and 78 % (18/23; 95 % CI: 61, 95) for reader 2. Kappa value was 0.86 (95 % CI: 0.47, 1.00). Readers 1 and 2 detected 35 and 36 lesions, respectively, all right-sided and agreed for 32 lesions on the type, location, and signal. Lesions were mostly nodules (23/32, 72 %), predominantly posterior (28/32, 87.5 %) and hyperintense on T1 (20/32, 63 %). MRI was negative for both readers in 2 surgically treated patients with small nodules or isolated diaphragmatic holes. CONCLUSION: MRI allows diaphragmatic endometriosis diagnosis with 78 to 83 % sensitivity and excellent interobserver agreement. KEY POINTS: • MRI allows the diagnosis of diaphragmatic endometriosis with up to 83 % sensitivity. • Diaphragmatic endometriosis lesions are better depicted on fat-suppressed T1-weighted sequences. • Diaphragmatic lesions, mostly hyperintense nodules, are right-sided and predominantly posterior. • MRI can help in timely diagnosis of diaphragmatic endometriosis.

French Interventional Radiology Centers' Uptake of Transradial Approach and Outpatient Hepatocellular Carcinoma Intra-Arterial Treatments.

PURPOSE: This study aims to investigate the uptake of transradial approach (TRA) and outpatient setting for transarterial chemoembolization (TACE) and transarterial radioembolization (TARE) in the treatment of hepatocellular carcinoma (HCC) among French interventional radiology centers. MATERIALS AND METHODS: This cross-sectional study was based on a 34-question survey assessing center activity, radial access, and outpatient care. The survey was developed by a working group, tested by two external experts, and distributed to active members of two French radiological societies via a web-based self-reporting questionnaire in March 2022. The survey remained open for eight weeks, with two reminder emails sent to non-responders. Only one answer per center was considered. RESULTS: Of the 44 responding centers, 39% (17/44) performed TRA for TACE and/or TARE, with post-procedure patient comfort as main motivation. Among the 27 centers not performing TRA, 33% (9/27) reported a lack of technical experience, but all 27 intended to adopt TRA within two years. Only six centers performed TACE or TARE in an outpatient setting. Reasons limiting its implementation included TACE for HCC not being a suitable intervention (61%, 27/44) and organizational barriers (41%, 18/44). Among centers not performing outpatient TACE or TARE, 34% (13/38) said "No," 34% (13/38) said "Maybe," and 32% (12/38) said "Yes" when asked about adopting it within two years. CONCLUSION: French interventional radiologists have low TRA uptake for HCC treatment, but TRA adoption potential exists. Respondents were uncertain about performing TACE or TARE in an outpatient setting within a 2-year horizon.

Primary liver cancer classification from routine tumour biopsy using weakly supervised deep learning.

Background & Aims: The diagnosis of primary liver cancers (PLCs) can be challenging, especially on biopsies and for combined hepatocellular-cholangiocarcinoma (cHCC-CCA). We automatically classified PLCs on routine-stained biopsies using a weakly supervised learning method. Method: We selected 166 PLC biopsies divided into training, internal and external validation sets: 90, 29 and 47 samples, respectively. Two liver pathologists reviewed each whole-slide hematein eosin saffron (HES)-stained image (WSI). After annotating the tumour/non-tumour areas, tiles of 256x256 pixels were extracted from the WSIs and used to train a ResNet18 neural network. The tumour/non-tumour annotations served as labels during training, and the network's last convolutional layer was used to extract new tumour tile features. Without knowledge of the precise labels of the malignancies, we then applied an unsupervised clustering algorithm. Results: Pathological review classified the training and validation sets into hepatocellular carcinoma (HCC, 33/90, 11/29 and 26/47), intrahepatic cholangiocarcinoma (iCCA, 28/90, 9/29 and 15/47), and cHCC-CCA (29/90, 9/29 and 6/47). In the two-cluster model, Clusters 0 and 1 contained mainly HCC and iCCA histological features. The diagnostic agreement between the pathological diagnosis and the two-cluster model predictions (major contingent) in the internal and external validation sets was 100% (11/11) and 96% (25/26) for HCC and 78% (7/9) and 87% (13/15) for iCCA, respectively. For cHCC-CCA, we observed a highly variable proportion of tiles from each cluster (cluster 0: 5-97%; cluster 1: 2-94%). Conclusion: Our method applied to PLC HES biopsy could identify specific morphological features of HCC and iCCA. Although no specific features of cHCC-CCA were recognized, assessing the proportion of HCC and iCCA tiles within a slide could facilitate the identification of cHCC-CCA. Impact and implications: The diagnosis of primary liver cancers can be challenging, especially on biopsies and for combined hepatocellular-cholangiocarcinoma (cHCC-CCA). We automatically classified primary liver cancers on routine-stained biopsies using a weakly supervised learning method. Our model identified specific features of hepatocellular carcinoma and intrahepatic cholangiocarcinoma. Despite no specific features of cHCC-CCA being recognized, the identification of hepatocellular carcinoma and intrahepatic cholangiocarcinoma tiles within a slide could facilitate the diagnosis of primary liver cancers, and particularly cHCC-CCA.