A Model for Predicting Clinically Significant Prostate Cancer using Prostate MRI and Risk Factors.

OBJECTIVE: To develop and validate a predictive model for clinically significant prostate cancer (csPCa) using prostate MRI and patient risk factors. METHODS: We identified 960 men who underwent MRI from 2015-2019 and biopsy either 6 months prior or 6 months following the MRI. We identified men diagnosed with csPCa and modeled csPCa risk using known patient factors (age, race, PSA) and prostate MRI findings (location, PI-RADS score, extraprostatic extension, dominant lesion size, PSA density [PSAD]). csPCa was defined as Gleason Sum ≥ 7. Using a derivation cohort, a multivariable logistic regression model and point-based scoring system were developed to predict csPCa. Discrimination and calibration were assessed in a separate independent validation cohort. RESULTS: 552 of 960 MRI reports (57.5%) were from men diagnosed with csPCa. Using the derivation cohort (n=632), variables that predicted csPCa were PI-RADS 4 and 5, presence of extraprostatic extension, and elevated PSAD. Evaluation using the validation cohort (n=328) resulted in AUC of 0.77, with adequate calibration (Hosmer-Lemeshow p=0.58). At a risk threshold of >2 points, the model identified csPCa with sensitivity of 98.4%, negative predictive value (NPV) of 78.6%, but only prevented 4.3% (0-2 points; 14/328) potential biopsies. At a higher threshold of >5 points, the model identified csPCA with sensitivity of 89.5%, NPV of 70.1%, and avoided 20.4% (0-5 points; 67/328) of biopsies. DISCUSSION: Our point-based model can potentially identify a vast majority of men at risk for csPCa, while sparing ∼ 1 in 5 men with an elevated PSA, a biopsy.

Magnetic Resonance Imaging, Clinical, and Biopsy Findings in Suspected Prostate Cancer: A Systematic Review and Meta-Analysis.

Importance: Multiple strategies integrating magnetic resonance imaging (MRI) and clinical data have been proposed to determine the need for a prostate biopsy in men with suspected clinically significant prostate cancer (csPCa) (Gleason score ≥3 + 4). However, inconsistencies across different strategies create challenges for drawing a definitive conclusion. Objective: To determine the optimal prostate biopsy decision-making strategy for avoiding unnecessary biopsies and minimizing the risk of missing csPCa by combining MRI Prostate Imaging Reporting & Data System (PI-RADS) and clinical data. Data Sources: PubMed, Ovid MEDLINE, Embase, Web of Science, and Cochrane Library from inception to July 1, 2022. Study Selection: English-language studies that evaluated men with suspected but not confirmed csPCa who underwent MRI PI-RADS followed by prostate biopsy were included. Each study had proposed a biopsy plan by combining PI-RADS and clinical data. Data Extraction and Synthesis: Studies were independently assessed for eligibility for inclusion. Quality of studies was appraised using the Quality Assessment of Diagnostic Accuracy Studies 2 tool and the Newcastle-Ottawa Scale. Mixed-effects meta-analyses and meta-regression models with multimodel inference were performed. Reporting of this study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Main Outcomes and Measures: Independent risk factors of csPCa were determined by performing meta-regression between the rate of csPCa and PI-RADS and clinical parameters. Yields of different biopsy strategies were assessed by performing diagnostic meta-analysis. Results: The analyses included 72 studies comprising 36 366 patients. Univariable meta-regression showed that PI-RADS 4 (ß-coefficient [SE], 7.82 [3.85]; P = .045) and PI-RADS 5 (ß-coefficient [SE], 23.18 [4.46]; P < .001) lesions, but not PI-RADS 3 lesions (ß-coefficient [SE], -4.08 [3.06]; P = .19), were significantly associated with a higher risk of csPCa. When considered jointly in a multivariable model, prostate-specific antigen density (PSAD) was the only clinical variable significantly associated with csPCa (ß-coefficient [SE], 15.50 [5.14]; P < .001) besides PI-RADS 5 (ß-coefficient [SE], 9.19 [3.33]; P < .001). Avoiding biopsy in patients with lesions with PI-RADS category of 3 or less and PSAD less than 0.10 (vs <0.15) ng/mL2 resulted in reducing 30% (vs 48%) of unnecessary biopsies (compared with performing biopsy in all suspected patients), with an estimated sensitivity of 97% (vs 95%) and number needed to harm of 17 (vs 15). Conclusions and Relevance: These findings suggest that in patients with suspected csPCa, patient-tailored prostate biopsy decisions based on PI-RADS and PSAD could prevent unnecessary procedures while maintaining high sensitivity.

Clinical indications, safety, and effectiveness of percutaneous image-guided adrenal mass biopsy: an 8-year retrospective analysis in 160 patients.

PURPOSE: To assess indications, safety, and effectiveness of percutaneous adrenal mass biopsy in contemporary practice. METHODS: This institutional review board-approved, retrospective study included all patients undergoing percutaneous image-guided adrenal mass biopsies at an academic health system from January 6, 2015, to January 6, 2023. Patient demographics, biopsy indications, mass size, laboratory data, pathology results, and complications were recorded. Final diagnoses were based on pathology or ≥ 1 year of imaging follow-up when biopsy specimens did not yield malignant tissue. Test performance calculations excluded repeat biopsies. Continuous variables were compared with Student's t test, dichotomous variables with chi-squared test. RESULTS: A total of 160 patients underwent 186 biopsies. Biopsies were indicated to diagnose metastatic disease (139/186; 74.7%), for oncologic research only (27/186; 14.5%), diagnose metastatic disease and oncologic research (15/186; 8%), and diagnose an incidental adrenal mass (5/186; 2.7%). Biopsy specimens were diagnostic in 154 patients (96.3%) and non-diagnostic in 6 (3.8%). Diagnostic biopsies yielded malignant tissue (n = 136), benign adrenal tissue (n = 12), and benign adrenal neoplasms (n = 6) with sensitivity = 98.6% (136/138), specificity = 100% (16/16), positive predictive value = 100% (136/136), and negative predictive value = 88.9% (16/18). Adverse events followed 11/186 procedures (5.9%) and most minor (7/11, 63.6%). The adverse event rate was similar whether tissue was obtained for clinical or research purposes (10/144; 6.9% vs. 1/42; 2.4%, p = 0.27), despite more specimens obtained for research (5.8 vs. 3.7, p < 0.001). CONCLUSION: Percutaneous adrenal mass biopsy is safe, accurate, and utilized almost exclusively to diagnose metastatic disease or for oncologic research. The negative predictive value is high when diagnostic tissue samples are obtained. Obtaining specimens for research does not increase adverse event risk.

A Multicenter Study of Needle Size and Safety for Splenic Biopsy.

Background Splenic biopsy is rarely performed because of the perceived risk of hemorrhagic complications. Purpose To evaluate the safety of large bore (≥18 gauge) image-guided splenic biopsy. Materials and Methods This retrospective study included consecutive adult patients who underwent US- or CT-guided splenic biopsy between March 2001 and March 2022 at eight academic institutions in the United States. Biopsies were performed with needles that were 18 gauge or larger, with a comparison group of biopsies with needles smaller than 18 gauge. The primary outcome was significant bleeding after the procedure, defined by the presence of bleeding at CT performed within 30 days or angiography and/or surgery performed to manage the bleeding. Categorical variables were compared using the χ2 test and medians were compared using the Mann-Whitney test. Results A total of 239 patients (median age, 63 years; IQR, 50-71 years; 116 of 239 [48.5%] female patients) underwent splenic biopsy with an 18-gauge or smaller needle and 139 patients (median age, 58 years [IQR, 49-69 years]; 66 of 139 [47.5%] female patients) underwent biopsy with a needle larger than 18 gauge. Bleeding was detected in 20 of 239 (8.4%) patients in the 18-gauge or smaller group and 11 of 139 (7.9%) in the larger than 18-gauge group. Bleeding was treated in five of 239 (2.1%) patients in the 18-gauge or smaller group and one of 139 (1%) in the larger than 18-gauge group. No deaths related to the biopsy procedure were recorded during the study period. Patients with bleeding after biopsy had smaller lesions compared with patients without bleeding (median, 2.1 cm [IQR, 1.6-5.4 cm] vs 3.5 cm [IQR, 2-6.8 cm], respectively; P = .03). Patients with a history of lymphoma or leukemia showed a lower incidence of bleeding than patients without this history (three of 90 [3%] vs 28 of 288 [9.7%], respectively; P = .05). Conclusion Bleeding after splenic biopsy with a needle 18 gauge or larger was similar to biopsy with a needle smaller than 18 gauge and seen in 8% of procedures overall, with 2% overall requiring treatment. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Grant in this issue.

Interventional Radiology Peer Learning Platform and Adverse Event Reporting (IR-PEER): Initial Experience Implementing a Team-based Novel Peer Learning System in Interventional Radiology.

Although the transition from peer review to peer learning has had favorable outcomes in diagnostic radiology, experience with implementing a team-based peer review system in interventional radiology (IR) remains limited. Peer learning systems benefit diverse IR teams composed of multiple clinical roles and could contribute value in archiving events that have potential educational value. With multiple stakeholder input from clinical roles within the IR division at our institution (ie, radiologic technologists, nurses, advanced practice providers, residents, fellows, and attending physicians), we launched a HIPAA-compliant secure IR complication and learning opportunity reporting platform in April 2022. Case submissions were monitored over the subsequent 24 weeks, with monthly dashboard reports provided to departmental leadership. Preintervention and postintervention surveys were used to assess the impact of the peer learning platform and adverse event reporting in IR (IR-PEER) on perceptions of complication reporting in the IR division across clinical roles. Ninety-two peer learning submissions were collected for a weekly average ± standard error of 3.8 ± 0.6 submissions per week, and an additional 26 submissions were collected as part of the division's ongoing monthly complication review conference, for a total of 98 unique total case references. A total of 64.1% of submissions (59 of 92) involved a complication and/or adverse event, and 35.9% of submissions (33 of 92) identified a learning opportunity (no complication or adverse event). Nurses reported that IR-PEER made the complication-reporting process easier (P = .01), and all clinical roles reported that IR-PEER improved the overall process of complication reporting. Peer learning frameworks such as IR-PEER provide a more equitable communication platform for multidisciplinary teams to capture and archive learning opportunities that support quality and safety improvement efforts.

Development and Validation of a Risk Model for Predicting Contrast-Associated Acute Kidney Injury in Patients With Cancer: Evaluation in Over 46,000 CT Examinations.

BACKGROUND. Patients with cancer undergo frequent CT examinations with iodinated contrast media and may be uniquely predisposed to contrast-associated acute kidney injury (CA-AKI). OBJECTIVE. The purpose of this study was to develop and validate a model for predicting the risk of CA-AKI after contrast-enhanced CT in patients with cancer. METHODS. This retrospective study included 25,184 adult patients (12,153 men, 13,031 women; mean age, 62.3 ± 13.7 [SD] years) with cancer who underwent 46,593 contrast-enhanced CT examinations between January 1, 2016, and June 20, 2020, at one of three academic medical centers. Information was recorded regarding demographics, malignancy type, medication use, baseline laboratory values, and comorbid conditions. CA-AKI was defined as a 0.3-mg/dL or greater increase in serum creatinine level from baseline within 48 hours after CT or a 1.5-fold or greater increase in the peak measurement within 14 days after CT. Multivariable models accounting for correlated data were used to identify risk factors for CA-AKI. A risk score for predicting CA-AKI was generated in a development set (n = 30,926) and tested in a validation set (n = 15,667). RESULTS. CA-AKI occurred after 5.8% (2682/46,593) of CT examinations. The final multivariable model for predicting CA-AKI included hematologic malignancy, diuretic use, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use, chronic kidney disease (CKD) stage 3a, CKD stage 3b, CKD stage 4 or 5, serum albumin level less than 3.0 g/dL, platelet count less than 150 × 103/µL, 1+ or greater proteinuria on baseline urinalysis, diabetes mellitus, heart failure, and contrast medium volume 100 mL or greater. A risk score (range, 0-53 points) was generated with these variables. The most points (13) were for CKD stage 4 or 5 and for albumin level less than 3 g/dL. The frequency of CA-AKI progressively increased in higher risk categories. For example, in the validation set, CA-AKI occurred after 2.2% of CT examinations in the lowest risk category (score ≤ 4) and after 32.7% of CT examinations in the highest risk category (score ≥ 30). The Hosmer-Lemeshow test result indicated that the risk score was a good fit (p = .40). CONCLUSION. A risk model in which readily available clinical data are used to predict the likelihood of CA-AKI after contrast-enhanced CT in patients with cancer was developed and validated. CLINICAL IMPACT. The model may help facilitate appropriate implementation of preventive measures in the care of patients at high risk of CA-AKI.

Can 3-Phase Computed Tomography Urography Be Used to Characterize Adrenal Nodules? Results in 145 Patients.

OBJECTIVE: The aim of the study is to determine whether computed tomography (CT) urography (CTU) can characterize incidental adrenal nodules. METHODS: This retrospective cohort study was performed at an academic medical center. Patients were identified by free text search of CTU reports that contained the terms "adrenal mass" "adrenal nodule" and "adrenal lesion." Computed tomography urography technique consisted of unenhanced images and postcontrast images obtained at 100 seconds and 15 minutes. The final cohort included 145 patients with 151 adrenal nodules. Nodules were considered lipid-rich adenomas or myelolipomas based on unenhanced imaging characteristics. Absolute and relative washout values were calculated for the remaining nodules, using a cutoff of 60% and 40%, respectively, to diagnose adenomas. Reference standard for lipid-poor adenomas and malignant nodules was histopathology or imaging/clinical follow-up. Mann-Whitney U test was used for comparison of continuous variables, and Fisher exact test was used for categorical variables. RESULTS: One hundred nodules were lipid-rich adenomas and 3 were myelolipomas. Forty-eight nodules were indeterminate at unenhanced CT, corresponding to 39 lipid-poor adenomas and 9 malignant nodules based on reference standards. Both absolute and relative washout correctly characterized 71% of nodules (34/48), with a sensitivity of 67% and specificity of 89%. Overall, 91% of all adrenal nodules (137/151) were correctly characterized by CTU alone. Lipid-poor adenomas were smaller than malignant nodules ( P < 0.01) and were lower in attenuation on unenhanced and delayed images ( P < 0.01). CONCLUSIONS: Adrenal nodules detected at 3-phase CTU can be accurately characterized, potentially eliminating the need for subsequent adrenal protocol CT or magnetic resonance imaging.

Comparing thoracic and abdominal subspecialists' follow-up recommendations for abdominal findings identified on chest CT.

PURPOSE: To compare thoracic and abdominal radiologists' follow-up recommendations for abdominal findings identified on chest CT. METHODS: This Institutional Review Board-exempt, retrospective study was performed at a large academic medical center with subspecialty radiology divisions. We used a combination of natural language processing and manual reviews to identify chest CT reports with and without abdominal findings that were interpreted by thoracic radiologists in 2019. Three random samples of reports were reviewed by two subspecialty trained abdominal radiologists for their agreement with thoracic radiologists' reporting: abdominal findings with follow-up recommendation (Group 1), abdominal findings without follow-up recommendation (Group 2), and no abdominal findings reported (Group 3). Primary outcome was agreement between thoracic and abdominal radiologists for the need for follow-up of abdominal findings. Secondary outcomes were agreement between subspecialists for the presence of abdominal findings and referring clinician adherence to recommendations. Fischer's exact test was used to compare proportions. RESULTS: Abdominal radiologists agreed with need for follow-up in 48.5% (16/33) of Group 1 cases and agreed follow-up was not necessary for 100% (34/34) of Group 2 cases (p < 0.001). Abdominal radiologists identified abdominal findings in 31.4% (11/35) of Group 3 cases, none of which required follow-up. Referring clinician adherence to thoracic radiologist follow-up recommendations for abdominal findings was 13/33 (39.4%). CONCLUSION: Abdominal radiologists frequently disagreed with thoracic radiologist recommendations for follow-up of abdominal findings on chest CT. Chest radiologists may consider abdominal subspecialty consultation or clinical decision support to reduce unnecessary imaging.

Frequency and Clinical Utility of Alerts for Intra-Institutional Radiologist Discrepant Opinions.

OBJECTIVE: Determine the rate of documented notification, via an alert, for intra-institutional discrepant radiologist opinions and addended reports and resulting clinical management changes. METHODS: This institutional review board-exempt, retrospective study was performed at a large academic medical center. We defined an intra-institutional discrepant opinion as when a consultant radiologist provides a different interpretation from that formally rendered by a colleague at our institution. We implemented a discrepant opinion policy requiring closed-loop notification of the consulting radiologist's second opinion to the original radiologist, who must acknowledge this alert within 30 days. This study included all discrepant opinion alerts created December 1, 2019, to December 31, 2021, of which two radiologists and an internal medicine physician performed consensus review. Primary outcomes were degree of discrepancy and percent of discrepant opinions leading to change in clinical management. Secondary outcome was report addendum rate compared with an existing peer learning program using Fisher's exact test. RESULTS: Of 114 discrepant opinion alerts among 1,888,147 reports generated during the study period (0.006%), 58 alerts were categorized as major (50.9%), 41 as moderate (36.0%), and 15 as minor discrepancies (13.1%). Clinical management change occurred in 64 of 114 cases (56.1%). Report addendum rate for discrepant opinion alerts was 4-fold higher than for peer learning alerts at our institution (66 of 315 = 21% versus 432 of 8,273 =5.2%; P < .0001). DISCUSSION: Although discrepant intra-institutional radiologist second opinions were rare, they frequently led to changes in clinical management. Capturing these discrepancies by encouraging alert use may help optimize patient care and document what was communicated to the referring or consulting care team by consulting radiologists.

Dual Energy-Derived Metrics for Differentiating Adrenal Adenomas From Nonadenomas on Single-Phase Contrast-Enhanced CT.

BACKGROUND. Adrenal masses are often indeterminate on single-phase postcontrast CT. Dual-energy CT (DECT) with three-material decomposition algorithms may aid characterization. OBJECTIVE. The purpose of this study was to compare the diagnostic performance of metrics derived from portal venous phase DECT, including virtual noncontrast (VNC) attenuation, fat fraction, iodine density, and relative enhancement ratio, for characterizing adrenal masses. METHODS. This retrospective study included 128 patients (82 women, 46 men; mean age, 64.6 ± 12.7 [SD] years) who between January 2016 and December 2019 underwent portal venous phase abdominopelvic DECT that showed a total of 139 adrenal lesions with an available reference standard based on all imaging, clinical, and pathologic records (87 adenomas, 52 nonadenomas [48 metastases, two adrenal cortical carcinomas, one ganglioneuroma, one hematoma]). Two radiologists placed ROIs to determine the following characteristics of the masses: VNC attenuation, fat fraction, iodine density normalized to portal vein, and for masses with VNC greater than 10 HU, relative enhancement ratio (ratio of portal venous phase attenuation to VNC attenuation). Readers' mean measurements were used for ROC analyses, and clinically optimal thresholds were derived as thresholds yielding the highest sensitivity at 100% specificity. RESULTS. Adenomas and nonadenomas were significantly different (all p < .001) in VNC attenuation (mean ± SD, 18.5 ± 12.9 vs 34.1 ± 8.9 HU), fat fraction (mean ± SD, 24.3% ± 8.2% vs 14.2% ± 5.6%), normalized iodine density (mean ± SD, 0.34 ± 0.15 vs 0.17 ± 0.17), and relative enhancement ratio (mean ± SD, 186% ± 96% vs 58% ± 59%). AUCs for all metrics ranged from 0.81 through 0.91. The metric with highest sensitivity for adenoma at the clinically optimal threshold (i.e., 100% specificity) was fat fraction (threshold, ≥ 23.8%; sensitivity, 59% [95% CI, 48-69%]) followed by VNC attenuation (≤ 15.2 HU; sensitivity, 39% [95% CI, 29-50%]), relative enhancement ratio (≥ 214%; sensitivity, 37% [95% CI, 25-50%]), and normalized iodine density (≥ 0.90; sensitivity, 1% (95% CI, 0-60%]). VNC attenuation at the traditional true noncontrast attenuation threshold of 10 HU or lower had sensitivity of 28% (95% CI, 19-38%) and 100% specificity. Presence of fat fraction 23.8% or greater or relative enhancement ratio 214% or greater yielded sensitivity of 68% (95% CI, 57-77%) with 100% specificity. CONCLUSION. For adrenal lesions evaluated with single-phase DECT, fat fraction had higher sensitivity than VNC attenuation at both the clinically optimal threshold and the traditional threshold of 10 HU or lower. CLINICAL IMPACT. By helping to definitively diagnose adenomas, DECT-derived metrics can help avoid downstream imaging for incidental adrenal lesions.

Lexicon for adrenal terms at CT and MRI: a consensus of the Society of Abdominal Radiology adrenal neoplasm disease-focused panel.

PURPOSE: Substantial variation in imaging terms used to describe the adrenal gland and adrenal findings leads to ambiguity and uncertainty in radiology reports and subsequently their understanding by referring clinicians. The purpose of this study was to develop a standardized lexicon to describe adrenal imaging findings at CT and MRI. METHODS: Fourteen members of the Society of Abdominal Radiology adrenal neoplasm disease-focused panel (SAR-DFP) including one endocrine surgeon participated to develop an adrenal lexicon using a modified Delphi process to reach consensus. Five radiologists prepared a preliminary list of 35 imaging terms that was sent to the full group as an online survey (19 general imaging terms, 9 specific to CT, and 7 specific to MRI). In the first round, members voted on terms to be included and proposed definitions; subsequent two rounds were used to achieve consensus on definitions (defined as ≥ 80% agreement). RESULTS: Consensus for inclusion was reached on 33/35 terms with two terms excluded (anterior limb and normal adrenal size measurements). Greater than 80% consensus was reached on the definitions for 15 terms following the first round, with subsequent consensus achieved for the definitions of the remaining 18 terms following two additional rounds. No included term had remaining disagreement. CONCLUSION: Expert consensus produced a standardized lexicon for reporting adrenal findings at CT and MRI. The use of this consensus lexicon should improve radiology report clarity, standardize clinical and research terminology, and reduce uncertainty for referring providers when adrenal findings are present.

Electronic Health Record Order Entry-Based Interventions in Response to a Global Iodinated Contrast Media Shortage: Impact on Contrast-Enhanced CT Utilization.

BACKGROUND. Radiology informatics systems and clinical decision support tools in the electronic health record (EHR) can be leveraged to help impact ordering patterns in response to the ongoing global iodinated contrast media shortage. OBJECTIVE. The purpose of our study was to assess the impact of EHR order entry-based interventions, implemented as part of a health system's response to the global contrast media shortage, on contrast-enhanced CT utilization. METHODS. This retrospective study included 79,259 patients who underwent CT at a large multisite health system between April 1, 2022, and July 3, 2022. Two EHR-based interventions were implemented as part of the health system's response to the global contrast media shortage. A first EHR-based intervention on May 10, 2022, entailed creating an alert that appeared in a sidebar after any contrast-enhanced body CT orders, indicating the present shortage and recommending alternate imaging modalities. A second EHR-based intervention on May 16, 2022, required referrers to enter detailed clinical information for all contrast-enhanced body CT orders, which radiologists used when protocoling examinations. Data regarding CT orders and examinations performed were extracted from the electronic data warehouse. RESULTS. During the preintervention, first postintervention, and second postintervention periods, the mean number of patients who underwent contrast-enhanced CT per weekday was 726, 689, and 639, respectively (p for preintervention vs second postintervention periods, < .001). During the three periods, the mean number of patients who underwent CT per weekday was 1350, 1323, and 1314 (p < .001). During the three periods, the mean number of patients who underwent contrast-enhanced body CT per weekday was 561, 532, and 492 (p < .001). During the three periods, the mean number of orders for CT with IV contrast media per weekday was 154, 143, and 131 (p < .001). During the three periods, the mean number of orders for CT without IV contrast media per weekday was 196, 202, and 221 (p < .001). CONCLUSION. EHR order entry-based interventions implemented in response to the global contrast media shortage significantly reduced contrast-enhanced CT utilization in a large health system. CLINICAL IMPACT. The findings indicate the ability to rapidly achieve changes in ordering clinician behavior and subsequent clinical practice using systemwide EHR changes.

Machine Learning for Adrenal Gland Segmentation and Classification of Normal and Adrenal Masses at CT.

Background Adrenal masses are common, but radiology reporting and recommendations for management can be variable. Purpose To create a machine learning algorithm to segment adrenal glands on contrast-enhanced CT images and classify glands as normal or mass-containing and to assess algorithm performance. Materials and Methods This retrospective study included two groups of contrast-enhanced abdominal CT examinations (development data set and secondary test set). Adrenal glands in the development data set were manually segmented by radiologists. Images in both the development data set and the secondary test set were manually classified as normal or mass-containing. Deep learning segmentation and classification models were trained on the development data set and evaluated on both data sets. Segmentation performance was evaluated with use of the Dice similarity coefficient (DSC), and classification performance with use of sensitivity and specificity. Results The development data set contained 274 CT examinations (251 patients; median age, 61 years; 133 women), and the secondary test set contained 991 CT examinations (991 patients; median age, 62 years; 578 women). The median model DSC on the development test set was 0.80 (IQR, 0.78-0.89) for normal glands and 0.84 (IQR, 0.79-0.90) for adrenal masses. On the development reader set, the median interreader DSC was 0.89 (IQR, 0.78-0.93) for normal glands and 0.89 (IQR, 0.85-0.97) for adrenal masses. Interreader DSC for radiologist manual segmentation did not differ from automated machine segmentation (P = .35). On the development test set, the model had a classification sensitivity of 83% (95% CI: 55, 95) and specificity of 89% (95% CI: 75, 96). On the secondary test set, the model had a classification sensitivity of 69% (95% CI: 58, 79) and specificity of 91% (95% CI: 90, 92). Conclusion A two-stage machine learning pipeline was able to segment the adrenal glands and differentiate normal adrenal glands from those containing masses. © RSNA, 2022 Online supplemental material is available for this article.

Safety of image guided research biopsies in patients with thoracic malignancies.

OBJECTIVE: A common opportunity to collect research samples is during image-guided percutaneous core needle biopsies (CNBs) performed when clinically indicated or for assessing clinical trial eligibility. The relative safety of extra CNBs collected for research is undefined. MATERIALS AND METHODS: Patients who underwent CNB for research purposes only [RO], as clinically indicated [CI], or as part of a clinical trial [CT] were identified. 30-day post-procedure adverse events (AEs) among the cohorts were examined and compared to the 2020 Society of Interventional Radiology QI guidelines. RESULTS: 236 patients with thoracic cancers (90 % NSCLC, 5 % SCLC, 4 % mesothelioma, and 1 % thymic) had 292 CNBs (63 RO, 229 CI + CT). AEs occurred in 13 % of both the RO and CI + CT groups. Compared to the CI + CT group, the RO group did not have a higher pneumothorax incidence (RO: 5/29 [17 %], CI + CT: 18/114 [16 %], p = 0.79); both were below the suggested QI threshold of 45 % for pneumothorax. There was a negative association between number of cores obtained and risk of AE (AE vs no AE mean cores = 3.5 vs 4.8). After adjusting for the number of cores and smoking history, RO vs CI + CT lung biopsies had a higher risk of AEs (adjusted relative risk [aRR] = 2.44, 1.08-5.55, p = 0.03 vs non-lung aRR = 0.86, 0.10-7.09, p = 0.89). CONCLUSION: CNBs performed for research purposes do not have a significantly increased risk of AEs when compared to those performed for clinical trials and/or when clinically indicated. However, AEs were most frequent in lung biopsies. When performing research biopsies, a target other than lung may be preferred when clinically appropriate.

Assessment of a Large-Scale Peer Learning Program's Value by Manual Review of Case Submissions.

OBJECTIVE: Prior studies used submission numbers or report addendum rates to measure peer learning programs' (PLP) impact. We assessed the educational value of a PLP by manually reviewing cases submitted to identify factors correlating with meaningful learning opportunities (MLOs). METHODS: This institutional review board-exempted, retrospective study was performed in a large academic radiology department generating >800,000 reports annually. A PLP facilitating radiologist-to-radiologist feedback was implemented May 1, 2017, with subsequent pay-for-performance initiatives encouraging increasing submissions, >18,000 by 2019. Two radiologists blinded to submitter and receiver identity categorized 336 randomly selected submissions as a MLO, not meaningful, or equivocal, resolving disagreements in consensus review. Primary outcome was proportion of MLOs. Secondary outcomes included percent engagement by subspecialty clinical division and comparing MLO and report addendum rates via Fisher's exact tests. We assessed association between peer learning category, pay-for-performance interventions, and subspecialty division with MLOs using logistic regression. RESULTS: Of 336 PLP submissions, 65.2% (219 of 336) were categorized as meaningful, 27.4% (92 of 336) not meaningful, and 7.4% (25 of 336) equivocal, with substantial reviewer agreement (86.0% [289 of 336], κ = 0.71, 95% confidence interval 0.64-0.78). MLO rate (65.2% [219 of 336]) was five times higher than addendum rate (12.9% [43 of 333]) for the cohort. MLO proportion (adjusted odds ratios 0.05-1.09) and percent engagement (0.5%-3.6%) varied between subspecialty divisions, some submitting significantly fewer MLOs (P < .01). MLO proportion did not vary between peer learning categories. CONCLUSION: Educational value of a large-scale PLP, estimated through manual review of case submissions, is likely a more accurate measure of program impact. Incentives to enhance PLP use did not diminish the program's educational value.