Diagnostic radiology training for medical students - a Brazilian multicenter survey.

OBJECTIVE: This study aimed to assess diagnostic radiology training and exposure during medical school, from the perspective of medical students in Brazil. METHODS: In this multicenter study approved by the Institutional Review Board, medical students from multiple universities in Brazil filled out an online questionnaire regarding their perception about diagnostic radiology training during medical school, including knowledge and use of the American College of Radiology Appropriateness Criteria and their confidence level in interpreting common radiological findings. Medical students from different regions of Brazil were sent invitations to participate in the anonymous survey through radiology group emails initiated by radiology professors and a group of ambassadors representing different institutions. Informed consent was obtained electronically at the beginning of the survey. RESULTS: The survey demonstrated diagnostic radiology is frequently included in preclinical exams; however, radiology training during medical school was considered inadequate from the medical students´ perspective. Overall, radiological imaging teaching was provided by radiologists for more than half of the survey respondents; however, radiological imaging is frequently shown to students by non-radiologist physicians during case discussion rounds. Moreover, few respondents had a mandatory radiology training rotation during medical school. CONCLUSION: This Brazilian medical student survey demonstrated that from the medical students' perspective, diagnostic radiology is an important subject in clinical practice; however, their radiology training and exposure are overall heterogeneous.

Diagnostic radiology training for medical students - a Brazilian multicenter survey

ABSTRACT Objective This study aimed to assess diagnostic radiology training and exposure during medical school, from the perspective of medical students in Brazil. Methods In this multicenter study approved by the Institutional Review Board, medical students from multiple universities in Brazil filled out an online questionnaire regarding their perception about diagnostic radiology training during medical school, including knowledge and use of the American College of Radiology Appropriateness Criteria and their confidence level in interpreting common radiological findings. Medical students from different regions of Brazil were sent invitations to participate in the anonymous survey through radiology group emails initiated by radiology professors and a group of ambassadors representing different institutions. Informed consent was obtained electronically at the beginning of the survey. Results The survey demonstrated diagnostic radiology is frequently included in preclinical exams; however, radiology training during medical school was considered inadequate from the medical students´ perspective. Overall, radiological imaging teaching was provided by radiologists for more than half of the survey respondents; however, radiological imaging is frequently shown to students by non-radiologist physicians during case discussion rounds. Moreover, few respondents had a mandatory radiology training rotation during medical school. Conclusion This Brazilian medical student survey demonstrated that from the medical students' perspective, diagnostic radiology is an important subject in clinical practice; however, their radiology training and exposure are overall heterogeneous.

Radiomic analysis of MRI to Predict Sustained Complete Response after Radiofrequency Ablation in Patients with Hepatocellular Carcinoma - A Pilot Study.

OBJECTIVES: To investigate whether quantitative textural features, extracted from pretreatment MRI, can predict sustained complete response to radiofrequency ablation (RFA) in patients with hepatocellular carcinoma (HCC). METHODS: In this IRB-approved study, patients were selected from a maintained six-year database of consecutive patients who underwent both pretreatment MRI imaging with a probable or definitive imaging diagnosis of HCC (LI-RADS 4 or 5) and loco-regional treatment with RFA. An experienced radiologist manually segmented the hepatic nodules in MRI arterial and equilibrium phases to obtain the volume of interest (VOI) for extraction of 107 quantitative textural features, including shape and first- and second-order features. Statistical analysis was performed to evaluate associations between textural features and complete response. RESULTS: The study consisted of 34 patients with 51 treated hepatic nodules. Sustained complete response was achieved by 6 patients (4 with single nodule and 2 with multiple nodules). Of the 107 features from the arterial and equilibrium phases, 20 (18%) and 25 (23%) achieved AUC >0.7, respectively. The three best performing features were found in the equilibrium phase: Dependence Non-Uniformity Normalized and Dependence Variance (both GLDM class, with AUC of 0.78 and 0.76, respectively) and Maximum Probability (GLCM class, AUC of 0.76). CONCLUSIONS: This pilot study demonstrates that a radiomic analysis of pre-treatment MRI might be useful in identifying patients with HCC who are most likely to have a sustained complete response to RFA. Second-order features (GLDM and GLCM) extracted from equilibrium phase obtained highest discriminatory performance.

Radiomic analysis of mri to predict sustained complete response after radiofrequency ablation in patients with hepatocellular carcinoma - a pilot study

OBJECTIVES: To investigate whether quantitative textural features, extracted from pretreatment MRI, can predict sustained complete response to radiofrequency ablation (RFA) in patients with hepatocellular carcinoma (HCC). METHODS: In this IRB-approved study, patients were selected from a maintained six-year database of consecutive patients who underwent both pretreatment MRI imaging with a probable or definitive imaging diagnosis of HCC (LI-RADS 4 or 5) and loco-regional treatment with RFA. An experienced radiologist manually segmented the hepatic nodules in MRI arterial and equilibrium phases to obtain the volume of interest (VOI) for extraction of 107 quantitative textural features, including shape and first- and second-order features. Statistical analysis was performed to evaluate associations between textural features and complete response. RESULTS: The study consisted of 34 patients with 51 treated hepatic nodules. Sustained complete response was achieved by 6 patients (4 with single nodule and 2 with multiple nodules). Of the 107 features from the arterial and equilibrium phases, 20 (18%) and 25 (23%) achieved AUC >0.7, respectively. The three best performing features were found in the equilibrium phase: Dependence Non-Uniformity Normalized and Dependence Variance (both GLDM class, with AUC of 0.78 and 0.76, respectively) and Maximum Probability (GLCM class, AUC of 0.76). CONCLUSIONS: This pilot study demonstrates that a radiomic analysis of pre-treatment MRI might be useful in identifying patients with HCC who are most likely to have a sustained complete response to RFA. Second-order features (GLDM and GLCM) extracted from equilibrium phase obtained highest discriminatory performance.

Lung radiofrequency ablation: post-procedure imaging patterns and late follow-up.

PURPOSE: To describe expected imaging features on chest computed tomography (CT) after percutaneous radiofrequency ablation (RFA) of lung tumors, and their frequency over time after the procedure. METHODS: In this double-center retrospective study, we reviewed CT scans from patients who underwent RFA for primary or secondary lung tumors. Patients with partial ablation or tumor recurrence during the imaging follow-up were not included. The imaging features were assessed in pre-defined time points: immediate post-procedure, ≤4 weeks, 5-24 weeks, 25-52 weeks and ≥52 weeks. Late follow-up (3 and 5 years after procedure) was assessed clinically in 48 patients. RESULTS: The study population consisted of 69 patients and 144 pulmonary tumors. Six out of 69 (9%) patients had primary lung nodules (stage I) and 63/69 (91 %) had metastatic pulmonary nodules. In a patient-level analysis, immediately after lung RFA, the most common CT features were ground glass opacities (66/69, 96 %), consolidation (56/69, 81 %), and hyperdensity within the nodule (47/69, 68 %). Less than 4 weeks, ground glass opacities (including reversed halo sign) was demonstrated in 20/22 (91 %) patients, while consolidation and pleural thickening were detected in 17/22 patients (77 %). Cavitation, pneumatocele, pneumothorax and pleural effusions were less common features. From 5 weeks onwards, the most common imaging features were parenchymal bands. CONCLUSIONS: Our study demonstrated the expected CT features after lung RFA, a safe and effective minimally invasive treatment for selected patients with primary and secondary lung tumors. Diagnostic and interventional radiologists should be familiar with the expected imaging features immediately after RFA and their change over time in order to avoid misinterpretation and inadequate treatments.

State of the art in magnetic resonance imaging of hepatocellular carcinoma.

Background Liver cancer is the sixth most common cancer worldwide and the second leading cause of cancer mortality. Chronic liver disease caused by viral infection, alcohol abuse, or other factors can lead to cirrhosis. Cirrhosis is the most important clinical risk factor for hepatocellular carcinoma (HCC) whereby the normal hepatic architecture is replaced by fibrous septa and a spectrum of nodules ranging from benign regenerative nodules to HCC, each one of them with different imaging features. Conclusions Furthermore, advanced techniques including the quantification of hepatic and intralesional fat and iron, magnetic resonance elastography, radiomics, radiogenomics, and positron emission tomography (PET)-MRI are highly promising for the extraction of new imaging biomarkers that reflect the tumor microenvironment and, in the future, may add decision-making value in the management of patients with HCC.

Multimodality Screening of Hepatic Nodules in Patients With Congenital Heart Disease After Fontan Procedure: Role of Ultrasound, ARFI Elastography, CT, and MRI.

OBJECTIVE: Currently, there is no consensus in the literature regarding the screening of hepatic nodules in patients who have undergone the Fontan procedure. The objectives of this study are to evaluate in this population the frequency of hepatic nodules at ultrasound (US), CT, and MRI; to measure liver stiffness using acoustic radiation force impulse (ARFI) elastography; and to investigate predictive factors for hepatic nodules. SUBJECTS AND METHODS: In this cross-sectional study, 49 patients who underwent the Fontan procedure were prospectively recruited from August 2014 through June 2016. These patients underwent clinical evaluation for hepatic disorders, ARFI elastography, US, CT, and MRI. RESULTS: Most of the patients had no symptoms, and hepatic nodules were detected in three of 49 (6.1%) patients at US, 14 of 44 (31.8%) patients at CT, and 19 of 48 (39.6%) patients at MRI. Liver stiffness at ARFI elastography was significantly higher in patients with hepatic nodules than in patients without such nodules (2.64 ± 0.81 m/s vs 1.94 ± 0.49 m/s; p = 0.002) and was a significant predictor of hepatic nodule (AUC, 0.767; p = 0.002). No clinical or laboratory data had any significant correlation with the existence of hepatic nodules, including time since Fontan procedure. CONCLUSION: In our study, more than one-third of patients had hepatic nodules at CT or MRI, but US did not detect most hepatic nodules. Liver stiffness at ARFI elastography was significantly higher in patients with hepatic nodules, and it may help guiding which patient should be further imaged with CT or MRI.