Radiology Education Amid COVID-19 Pandemic and Possible Solutions.

Along with the rest of the world, the United States is inundated by the COVID-19 pandemic. The medical services in the country have been severely affected. The pandemic poses extraordinary challenges to academic institutions including radiology residency and fellowship programs. Herein, we delineate major difficulties faced by our radiology training program and mitigating countermeasures. The primary objective is to discuss the changes in our radiology training programs due to COVID-19 to allow for continued radiology education.

Preresection Radiologic Assessment and Imaging Features of 156 Pathologically Proven Adrenal Adenomas.

PURPOSE: The aims of the study were to assess the typical and atypical radiologic features of pathologically proven adrenal adenomas and to determine the relationship between the radiologic and histopathologic classification. METHODS: We retrospectively studied 156 pathologically proven adrenal adenomas in 154 patients from our institutional databases who have computed tomography (CT) and/or magnetic resonance imaging (MRI) examinations before intervention. We determined the histopathologic diagnosis (typical or atypical) using Weiss scoring and classified the adenomas radiologically into typical, atypical, or indeterminate based on lesion size, precontrast CT attenuation, absolute percentage washout, calcification, and necrosis. The κ statistic was used to assess the agreement between radiologists. The Fisher exact test was used to compare the radiologic and pathological classifications. RESULTS: In consensus, there were 83 typical, 42 atypical, and 31 indeterminate adrenal lesions. Logistic regression model showed that radiologically atypical adenoma was significantly associated with larger size, lobulated shape, higher unenhanced CT attenuation, heterogeneous appearance, nonfunctioning status, absolute percentage washout of less than 60%, and a signal intensity index of less than 16.5%.Pathologically, 147 adenomas were pathologically typical (Weiss 0), and 9 adenomas were pathologically atypical (Weiss 1-2). Radiologically, there was substantial agreement between both readers, with Cohen κ at 0.71. Approximately 98% of radiologically typical adenomas were pathologically typical. Only 17% of radiologically atypical adenomas were pathologically atypical. All radiologically indeterminate adenomas were pathologically typical. However, some of the radiologically indeterminate and typical adenomas still had an atypical component on pathologic analysis, such as necrosis, nuclear atypia, or oncocytic features. CONCLUSIONS: Radiologically atypical lesion was significantly associated with larger size and higher unenhanced CT attenuation. Approximately 27% of the cases demonstrated atypical features on imaging. Most radiologically atypical adrenal adenomas are pathologically typical.

Image Quality Assessment of Abdominal CT by Use of New Deep Learning Image Reconstruction: Initial Experience.

OBJECTIVE. The purpose of this study was to perform quantitative and qualitative evaluation of a deep learning image reconstruction (DLIR) algorithm in contrast-enhanced oncologic CT of the abdomen. MATERIALS AND METHODS. Retrospective review (April-May 2019) of the cases of adults undergoing oncologic staging with portal venous phase abdominal CT was conducted for evaluation of standard 30% adaptive statistical iterative reconstruction V (30% ASIR-V) reconstruction compared with DLIR at low, medium, and high strengths. Attenuation and noise measurements were performed. Two radiologists, blinded to examination details, scored six categories while comparing reconstructions for overall image quality, lesion diagnostic confidence, artifacts, image noise and texture, lesion conspicuity, and resolution. RESULTS. DLIR had a better contrast-to-noise ratio than 30% ASIR-V did; high-strength DLIR performed the best. High-strength DLIR was associated with 47% reduction in noise, resulting in a 92-94% increase in contrast-to-noise ratio compared with that of 30% ASIR-V. For overall image quality and image noise and texture, DLIR scored significantly higher than 30% ASIR-V with significantly higher scores as DLIR strength increased. A total of 193 lesions were identified. The lesion diagnostic confidence, conspicuity, and artifact scores were significantly higher for all DLIR levels than for 30% ASIR-V. There was no significant difference in perceived resolution between the reconstruction methods. CONCLUSION. Compared with 30% ASIR-V, DLIR improved CT evaluation of the abdomen in the portal venous phase. DLIR strength should be chosen to balance the degree of desired denoising for a clinical task relative to mild blurring, which increases with progressively higher DLIR strengths.

FDG-PET Assessment of Other Gynecologic Cancers.

PET and PET/computed tomography play a role in the staging, monitoring of response to therapy, and surveillance for cervical and ovarian cancers. Currently, it is also an integral part of the assessment of patients with endometrial cancer and other gynecologic malignancies, such as vaginal and vulvar cancers and uterine sarcomas. In this article, we discuss in detail and highlight the potential role of PET and PET/computed tomography in evaluating these gynecologic malignancies using illustrative cases with relevant imaging findings.

Structured reporting of CT enterography for inflammatory bowel disease: effect on key feature reporting, accuracy across training levels, and subjective assessment of disease by referring physicians.

PURPOSE: To compare the content and accuracy of structured reporting (SR) versus non-structured reporting (NSR) for computed tomographic enterography (CTE) of inflammatory bowel disease (IBD). MATERIALS AND METHODS: This IRB-approved, HIPAA-compliant, retrospective study included 30 adult subjects (15 male, 15 female; mean age 41.9 years) with IBD imaged with CTE. Nine radiologists (3 faculty, 3 abdominal imaging fellows, and 3 senior radiology residents) independently interpreted all examinations using both NSR and SR, separated by four weeks. Reports were assessed for documentation of 15 key reporting features and a subset of 5 features was assessed for accuracy. Thirty faculty reports (15 NSR [5 per reader] and 15 SR [5 per reader]) were randomly selected for review by three referring physicians, who independently rated quality metrics for each report. RESULTS: NSR documented the presence or absence of 8.2 ± 2.2 key features, while SR documented 14.6 ± 0.5 features (p < 0.001). SR resulted in increased documentation of 13 of 15 features including stricture (p < 0.001), fistula (p < 0.001), fluid collection (p = 0.003), and perianal disease (p < 0.001). Among a subset of five features, accuracy for diagnosing multifocal disease was minimally increased when using SR (76% NSR vs. 83% SR; p = 0.01), but accuracy for other features was not affected by report type. Referring physicians significantly preferred SR based on ease of information extraction (p < 0.01). CONCLUSION: Structured reporting of CTE for IBD improved documentation of key reporting features for trainees and faculty, though there was minimal impact on accuracy. Referring physicians subjectively preferred the structured reports.

Preclinical assessment of a 980-nm diode laser ablation system in a large animal tumor model.

PURPOSE: To characterize the performance of a 980-nm diode laser ablation system in an in vivo tumor model. MATERIALS AND METHODS: This study was approved by the institutional animal care and use committee. The ablation system consisted of a 15-W, 980-nm diode laser, flexible diffusing-tipped fiber optic, and 17-gauge internally cooled catheter. Ten immunosuppressed dogs were inoculated subcutaneously with canine-transmissible venereal tumor fragments in eight dorsal locations. Laser ablations were performed at 79 sites where inoculations were successful (99%) at powers of 10 W, 12.5 W, and 15 W, with exposure times between 60 and 180 seconds. In 20 cases, multiple overlapping ablations were performed. After the dogs were euthanized, the tumors were harvested, sectioned along the applicator tract, measured, and photographed. Measurements of ablation zone were performed on gross specimen. Histopathology and viability staining was performed with hematoxylin and eosin and nicotinamide adenine dinucleotide hydrogen staining. RESULTS: Gross pathologic examination confirmed a well circumscribed ablation zone with sharp boundaries between thermally ablated tumor in the center surrounded by viable tumor tissue. When a single applicator was used, the greatest ablation diameters ranged from 12 mm at the lowest dose (10 W, 60 seconds) to 26 mm at the highest dose (15 W, 180 seconds). Multiple applicators created ablation zones as large as 42 mm in greatest diameter (with the lasers operating at 15 W for 120 seconds). CONCLUSIONS: The new 980-nm diode laser and internally cooled applicator effectively create large ellipsoid thermal ablations in less than 3 minutes.