Direct Quantification of Gadolinium Retention in Young Patients by ICP-MS Analysis of Extracted Teeth.

In this 10-patient prospective pilot study, we show feasibility of pragmatic, direct ex vivo measurement of gadolinium retention from group II gadolinium-based contrast agents (GBCAs) in young patients following routine tooth extraction. This noninvasive method may support future research attempting to understand the link between GBCA exposure and clinical outcomes.

Radiologists predict differential resource utilization but not clinical outcome in emergency department patients imaged with ultrasound for right upper quadrant pain.

PURPOSE: Radiologists with diverse training, specialization, and habits interpret imaging in the Emergency Department. It is necessary to understand if their variation predicts differential value. The purpose of this study was to determine whether attending radiologist variation predicts major clinical outcomes in adult Emergency Department patients imaged with ultrasound for right upper quadrant pain. METHODS: Consecutive ED patients imaged with ultrasound for RUQ pain from 10/8/2016 to 8/10/2022 were included (N = 7097). The primary outcome was prediction of hospital admission by signing attending radiologist. Secondary outcomes included: ED and hospital length of stay (LOS), 30-day mortality, 30-day re-presentation rate, subspecialty consultation, advanced imaging follow up (HIDA, MRI, CT), and intervention (ERCP, drainage or surgery). Sample size was determined a priori (detectable effect size: w = 0.06). Data were adjusted for demographic data, Elixhauser comorbidities, number of ED visits in prior year, clinical data, and system factors (38 covariates). P-values were corrected for multiple comparisons (false discovery rate-adjusted p-values). RESULTS: The included ultrasounds were read by 35 radiologists (median exams/radiologist: 145 [74.5-241.5]). Signing radiologist did not predict hospitalization (p = 0.85), abdominopelvic surgery or intervention within 30 days, re-presentation to the Emergency Department within 30 days, or subspecialty consultation. Radiologist did predict difference in Emergency Department length of stay (p < 0.001) although this difference was small and imprecise. HIDA was mentioned variably by radiologists (range 0-19%, p < 0.001), and mention of HIDA in the ultrasound report increased 10-fold the odds of HIDA being performed in the next 72 h (odds ratio 10.4 [8.0-13.4], p < 0.001). CONCLUSION: Radiologist variability did not predict meaningful outcome differences for patients with right upper quadrant pain undergoing ultrasound in the Emergency Department, but when radiologists mention HIDA in their reports, it predicts a 10-fold increase in the odds a HIDA is performed. Radiologists are relied on for interpretation that shapes subsequent patient care, and it is important to consider how radiologist variability can influence both outcome and resource utilization.

Continuity of Radiologists Between Diagnostic Breast Imaging and Image-Guided Breast Biopsy: Impact on Patient-Reported Biopsy Morbidity Experiences.

OBJECTIVE: To determine whether continuity of care between diagnostic breast imaging and subsequent image-guided breast biopsy could reduce patient-reported biopsy-related morbidity. METHODS: This was a prospective, pragmatically randomized, 2-arm health utilities analysis of 200 women undergoing diagnostic breast imaging followed by US- or stereotactic-guided breast biopsy at a single quaternary care center from September 3, 2019, to April 10, 2023. Breast biopsy-naive women with a BI-RADS 4 or 5 finding at diagnostic imaging were randomly scheduled for the typically first available biopsy appointment. One day after biopsy, enrolled patients were administered the Testing Morbidities Index (TMI). The primary outcome was the difference in TMI summary utility scores in patients who did vs did not have the same radiologist perform diagnostic imaging and biopsy. RESULTS: Response rates were 63% (100/159) for the different radiologist cohort and 71% (100/140) for the same radiologist cohort; all respondents answered all questions in both arms. Mean time to biopsy was 7 ± 6 days and 10 ± 9 days, and the number of participating radiologists was 11 and 18, respectively. There was no difference in individual measured domains (pain, fear, or anxiety before procedure; pain, embarrassment, fear, or anxiety during procedure; mental or physical impact after procedure; all P >.00625) or in overall patient morbidity (0.83 [95% CI, 0.81-0.85] vs 0.82 [95% CI: 0.80-0.84], P = .66). CONCLUSION: Continuity of care between diagnostic breast imaging and image-guided breast biopsy did not affect morbidity associated with breast biopsy, suggesting that patients should be scheduled for the soonest available biopsy appointment rather than waiting for the same radiologist.

Intra-practice Urologist-level Variation in Targeted Fusion Biopsy Outcomes.

OBJECTIVE: To examine the extent to which the urologist performing biopsy contributes to variation in prostate cancer detection during fusion-guided prostate biopsy. METHODS: All men in the Michigan Urological Surgery Improvement Collaborative (MUSIC) clinical registry who underwent fusion biopsy at Michigan Medicine from August 2017 to March 2019 were included. The primary outcomes were clinically significant cancer detection rate (defined as Gleason Grade ≥2) in targeted cores and clinically significant cancer detection on targeted cores stratified by PI-RADS score. Bivariate and multivariable logistic regression analyses were performed. RESULTS: A total of 1133 fusion biopsies performed by 5 providers were included. When adjusting for patient age, PSA, race, family history, prostate volume, clinical stage, and PI-RADS score, there was no significant difference in targeted clinically significant cancer detection rates across providers (range = 38.5%-46.9%, adjusted P-value = .575). Clinically significant cancer detection rates ranged from 11.1% to 16.7% in PI-RADS 3 (unadjusted P = .838), from 24.6% to 43.4% in PI-RADS 4 (adjusted P = .003), and from 69.4% to 78.8% in PI-RADS 5 (adjusted P = .766) lesions. CONCLUSION: There was a statistically significant difference in clinically significant prostate cancer detection in PI-RADS 4 lesions across providers. These findings suggest that even among experienced providers, variation at the urologist level may contribute to differences in clinically significant cancer detection rates within PI-RADS 4 lesions. However, the relative impact of biopsy technique, radiologist interpretation, and MR acquisition protocol requires further study.

Computerized Decision Support for Bladder Cancer Treatment Response Assessment in CT Urography: Effect on Diagnostic Accuracy in Multi-Institution Multi-Specialty Study.

This observer study investigates the effect of computerized artificial intelligence (AI)-based decision support system (CDSS-T) on physicians' diagnostic accuracy in assessing bladder cancer treatment response. The performance of 17 observers was evaluated when assessing bladder cancer treatment response without and with CDSS-T using pre- and post-chemotherapy CTU scans in 123 patients having 157 pre- and post-treatment cancer pairs. The impact of cancer case difficulty, observers' clinical experience, institution affiliation, specialty, and the assessment times on the observers' diagnostic performance with and without using CDSS-T were analyzed. It was found that the average performance of the 17 observers was significantly improved (p = 0.002) when aided by the CDSS-T. The cancer case difficulty, institution affiliation, specialty, and the assessment times influenced the observers' performance without CDSS-T. The AI-based decision support system has the potential to improve the diagnostic accuracy in assessing bladder cancer treatment response and result in more consistent performance among all physicians.

Effect of Prostate MRI Interpretation Experience on PPV Using PI-RADS Version 2: A 6-Year Assessment Among Eight Fellowship-Trained Radiologists.

BACKGROUND. Understanding the effect of specific experience in prostate MRI interpretation on diagnostic performance would help inform the minimum interpretation volume to establish proficiency. OBJECTIVE. The purpose of this article is to assess for an association between increasing experience in prostate MRI interpretation and change in radiologist-level PPVs for PI-RADS version 2 (v2) categories 3, 4, and 5. METHODS. This retrospective study included prostate MRI examinations performed between July 1, 2015, and August 13, 2021, that were assigned a PI-RADS v2 category of 3, 4, or 5 and with an MRI-ultrasound fusion biopsy available as the reference standard. All examinations were among the first 100-200 prostate MRI examinations interpreted using PI-RADS v2 by fellowship-trained abdominal radiologists. Radiologists received feedback through a quality assurance program. Radiologists' experience levels were classified using progressive subsets of 50 interpreted examinations. Change with increasing experience in distribution of individual radiologists' whole-gland PPVs for Gleason sum score 7 or greater prostate cancer, stratified by PI-RADS category, was assessed by hierarchic linear mixed models. RESULTS. The study included 1300 prostate MRI examinations in 1037 patients (mean age, 66 ± 7 [SD] years), interpreted by eight radiologists (median, 13 years of postfellow-ship experience; range, 5-22 years). Aggregate PPVs were 20% (68/340) for PI-RADS category 3, 49% (318/652) for category 4, and 71% (220/308) for category 5. Interquartile ranges (IQRs) of PPVs overlapped for category 4 (51%; IQR, 42-60%) and category 5 (70%; IQR, 54-75%) for radiologists' first 50 examinations. IQRs of PPVs did not overlap between categories of greater experience; for example, at the 101-150 examination level, PPV for category 3 was 24% (IQR, 20-29%), category 4 was 55% (IQR, 54-63%), and category 5 was 81% (IQR, 77-82%). Hierarchic modeling showed no change in radiologists' absolute PPV with increasing experience (category 3, p = .27; category 4, p = .71; category 5, p = .38). CONCLUSION. Absolute PPVs at specific PI-RADS categories did not change during radiologists' first 200 included examinations. However, resolution of initial overlap in IQRs indicates improved precision of PPVs after the first 50 examinations. CLINICAL IMPACT. If implementing a minimum training threshold for fellowship-trained abdominal radiologists, 50 prostate MRI examinations may be sufficient in the context of a quality assurance program with feedback.

Lessons Learned from Peer Learning Conference in Cardiothoracic Radiology.

Medical errors may lead to patient harm and may also have a devastating effect on medical providers, who may suffer from guilt and the personal impact of a given error (second victim experience). While it is important to recognize and remedy errors, it should be done in a way that leads to long-standing practice improvement and focuses on systems-level opportunities rather than in a punitive fashion. Traditional peer review systems are score based and have some undesirable attributes. The authors discuss the differences between traditional peer review systems and peer learning approaches and offer practical suggestions for transitioning to peer learning conferences. Peer learning conferences focus on learning opportunities and embrace errors as an opportunity to learn. The authors also discuss various types and sources of errors relevant to the practice of radiology and how discussions in peer learning conferences can lead to widespread system improvement. In the authors' experience, these strategies have resulted in practice improvement not only at a division level in radiology but in a broader multidisciplinary setting as well. The online slide presentation from the RSNA Annual Meeting is available for this article. ©RSNA, 2022.

Preoperative Prostate MRI Predictors of Urinary Continence Following Radical Prostatectomy.

Background Urinary continence after radical prostatectomy (RP) is an important determinant of patient quality of life. Anatomic measures at prostate MRI have been previously associated with continence outcomes, but their predictive ability and interrater agreement are unclear in comprehensive clinical models. Purpose To evaluate the predictive ability and interrater agreement of MRI-based anatomic measurements of post-RP continence when combined with clinical multivariable models. Materials and Methods In this retrospective cohort study, continence outcomes were evaluated in men who underwent RP from August 2015 to October 2019. Preoperative MRI-based anatomic measures were obtained retrospectively by four abdominal radiologists. Before participation, these radiologists completed measure-specific training. Logistic regression models were developed with clinical variables alone, MRI variables alone, and combined variables for predicting continence at 3, 6, and 12 months after RP; some patient data were missing at each time point. Interrater agreement of MRI variables was assessed by using intraclass correlation coefficients (ICCs). Results A total of 586 men were included (mean age ± standard deviation: 63 years ± 7). The proportion of patients with incontinence was 0.2% (one of 589) at baseline, 27% (145 of 529) at 3 months, 14% (63 of 465) at 6 months, and 9% (37 of 425) at 12 months. Longer coronal membranous urethra length (MUL) improved the odds of post-RP continence at all time points (odds ratio per 1 mm: 0.86 [95% CI: 0.80, 0.93], P < .001; 0.86 [95% CI: 0.78, 0.95], P = .003; and 0.79 [95% CI: 0.67, 0.91], P = .002, respectively) in models that incorporated both clinical and MRI predictors. No other MRI variables were predictive. Age and baseline urinary function score were the only other predictive clinical variables at every time point. Interrater agreement was moderate (ICC, 0.62) for MUL among readers with measure-specific prostate MRI training and poor among those without the training (ICC, 0.38). Conclusion Preoperative MRI-measured coronal membranous urethra length was an independent predictor of urinary continence after prostatectomy. © RSNA, 2022 Online supplemental material is available for this article.

Targeting Missed Care Opportunities Using Modern Communication Methods: A Quality Improvement Initiative to Improve Access to CT and MRI Appointments.

PURPOSE: To evaluate the impact of automated text and phone call reminder systems on CT (computed tomography) and MRI (magnetic resonance imaging) missed care opportunities. METHODS: This was an IRB (institutional review board) exempt prospective interventional quality improvement study. The proportion of missed care opportunities (appointment made, no imaging performed) related to scheduled CT and MRI examinations were evaluated over 2 months (Month 1: reminder phone calls by staff 48-96 hours prior and mailed letter 1-2 weeks prior; Month 2: no manual call or letter, automated text message 24 hours prior, automated phone call 72 hours prior, automated patient portal message 7 days prior). The proportion of missed care opportunities was calculated in aggregate and by modality. Process control p-charts were generated. An a priori power analysis was performed. Chi-squared tests were performed. p-value < 0.017 was considered significant after Bonferroni correction. RESULTS: Missed care opportunities occurred for 2.82% (292/10348; 95% CI: 2.51-3.16) of all CT and MRI appointments using traditional communication and 2.44% (262/10719; 95% CI: 2.16-2.75) using automated communication (p = 0.09). Automated messaging did not significantly change the proportion of missed care opportunities for CT (traditional: 2.62% [95% CI: 2.23-3.06] vs. automated: 2.06% [95% CI: 1.70-2.48], p = 0.05) or MRI (traditional: 3.1% [95% CI: 2.60-3.66] vs. automated: 2.83% [95% CI: 2.40-3.30], p = 0.43). Process control p-charts showed dominance of common cause variation. CONCLUSION: Automated messaging did not meaningfully change the overall proportion of missed care opportunities compared to traditional human-initiated phone calls. Automated communications may reduce cost and improve efficiency without adversely affecting access to care.

Interrater Agreement of Bosniak Classification Version 2019 and Version 2005 for Cystic Renal Masses at CT and MRI.

Background The Bosniak classification system for cystic renal masses was updated in 2019 in part to improve agreement compared with the 2005 version. Purpose To compare and investigate interrater agreement of Bosniak version 2019 and Bosniak version 2005 at CT and MRI. Materials and Methods In this retrospective single-center study, a blinded eight-reader assessment was performed in which 195 renal masses prospectively considered Bosniak IIF-IV (95 at CT, 100 at MRI, from 2006 to 2019 with version 2005) were re-evaluated with Bosniak versions 2019 and 2005. Radiologists (four faculty members, four residents) who were blinded to the initial clinical reading and histopathologic findings assessed all feature components and reported the overall Bosniak class for each system independently. Agreement was assessed with Gwet agreement coefficients. Uni- and multivariable linear regression models were developed to identify predictors of dispersion in the final Bosniak class assignment that could inform system refinement. Results A total of 185 patients were included (mean age, 63 years ± 13 [standard deviation]; 118 men). Overall interrater agreement was similar between Bosniak version 2019 and version 2005 (Gwet agreement coefficient: 0.51 [95% CI: 0.45, 0.57] vs 0.46 [95% CI: 0.42, 0.51]). This was true for experts (0.54 vs 0.49) and novices (0.50 vs 0.47) and at CT (0.56 vs 0.51) and MRI (0.52 vs 0.43). Nine percent of masses prospectively considered cystic using Bosniak version 2005 criteria were considered solid using version 2019 criteria. In general, masses were more commonly classified in lower categories when radiologists used Bosniak version 2019 criteria compared with version 2005 criteria. The sole predictor of dispersion in Bosniak version 2019 class assignment was dispersion in septa or wall quality (ie, smooth vs irregular thickening vs nodule; 72% [MRI] and 60% [CT] overall model variance explained; multivariable P < .001). Conclusion Overall interrater agreement was similar between Bosniak version 2019 and version 2005; disagreements in septa or wall quality were common and strongly predictive of variation in Bosniak class assignment. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Eberhardt in this issue.

Testing-Related Health Impact of Transrectal and Transperineal Prostate Biopsy as Assessed by Health Utilities.

PURPOSE: We sought to assess the temporary health-related quality of life (health utility) of nonmagnetic resonance imaging-guided transrectal and transperineal prostate biopsy. MATERIALS AND METHODS: This is a 2-arm, prospectively enrolled, observational, patient-reported outcomes study, performed between June 2019 and November 2020 at a single academic medical center. Inclusion criteria were men undergoing an outpatient ultrasound-guided prostate biopsy (transrectal or transperineal approach, without magnetic resonance imaging guidance). Patients with a history of Gleason 7+ prostate cancer were excluded. Validated survey instruments were utilized to assess baseline (Short Form 12) and testing-related (Testing Morbidities Index [TMI]) health utility states. The primary outcome was the TMI summary testing-related quality-of-life score (summary utility score; scale: 0=death and 1=perfect health). The TMI is comprised of 7 domains, spanning before, during and after testing experiences. Each domain is scored from 1 (no health impact) to 5 (extreme health impact). Testing-related quality-of-life measures were compared with Mann-Whitney U test. RESULTS: Enrollment rates were 80% (60/75; transrectal) and 86% (60/70; transperineal). All patients (120/120) completed the questionnaire. The TMI summary score for transrectal biopsy was not significantly different from transperineal biopsy (0.86, 95% CI 0.84-0.88 vs 0.83, 95% CI 0.81-0.85; p=0.0774). The largest difference in the testing experiences was related to intraprocedural pain (transrectal biopsy: 2.3, 95% CI 2.1-2.4; transperineal biopsy: 2.9, 95% CI 2.6-3.1; p <0.001). CONCLUSIONS: Transperineal and transrectal prostate biopsies have similar effect on temporary health-related quality-of-life. Transient differences relate to intraprocedural pain. These data can inform clinical decision making and future cost-utility models.

Extended dwell and standard ultrasound guided peripheral intravenous catheters: Comparison of durability and reliability.

Background Vascular access is a critical component of emergency department (ED) care. Ultrasound guided placement of peripheral intravenous (USIV) catheters is increasingly common. However, USIV are thought to suffer from reduced durability and higher complication rates. Extended dwell catheters (EDC) are long peripheral IVs placed under combined ultrasound and wire guidance. The goal of this study is to compare dwell times and complication rates of EDC to standard peripheral USIV. Methods We performed a retrospective cohort study at a tertiary care adult ED comparing IV placements during a 17-month period (8/1/2018-12/31/2019), stratified by standard USIV versus EDC. The primary outcome was catheter dwell time and secondary outcomes included need for inpatient vascular access team (VAST) consultation, peripherally inserted central catheter (PICC) insertions, and radiocontrast extravasations. Multivariable Cox regression time-to-event analyses were used to evaluate dwell times, adjusting for age, gender, BMI and end-stage renal disease. Results 359 EDC and 4190 standard USIV were included for analysis. Most USIV (95.6%) and EDC (98.3%) were placed by ED technicians trained in ultrasound vascular access. EDC median dwell time (5.9 days [95%CI: 5.1-6.7]) exceeded standard USIV (3.8 days [95% CI: 3.6-4.0]). Patients with EDC placed in the ED required less VAST consultation (0.84 vs 0.99 charges/encounter), had similar rates of PICC line use (8.0% vs 8.4% of encounters) and had no radiocontrast extravasation events. Multivariable Cox regression demonstrated survival benefit (longer dwell time) favoring EDC (HR 0.70 [95%CI 0.60-0.81]). Conclusion Use of EDC results in longer dwell time and reduces subsequent use of vascular access resources, while maintaining low complication rates. EDC demonstrate superior durability which may justify their selection over standard USIV in some patients.

Biopsy of the same organ within 30 days: a potential radiology performance measure.

PURPOSE: To assess the potential value of repeat image-guided biopsy within 30 days as a radiology performance metric. METHODS: This was a HIPAA-compliant IRB-approved retrospective cohort study of all consecutive ultrasound- and CT-guided core biopsies of the chest, abdomen, and pelvis performed at one institution November 2016 to June 2020. The inclusion criterion was repeat biopsy of the same organ within 30 days of the initial biopsy. Details of both biopsies were recorded, including indication, organ, post-biopsy histology, performing service, performing provider. Histologic concordance between initial and repeat biopsies was calculated. Proportions and 95% confidence intervals were calculated. RESULTS: Repeat biopsy was performed after 1.9% (95% CI 1.5-2.4% [N = 89]) of 4637 initial biopsies. For structures with ≥ 100 biopsies performed, the repeat biopsy proportion ranged from 1.3% (5/378, US-guided renal biopsy) to 2.7% (11/413, CT-guided retroperitoneal biopsy). The most common indication for initial biopsy was possible malignancy (66% [59/89]). The most common indication for repeat biopsy was radiology-histology discrepancy (36% [32/89]). Repeat biopsies were more likely to show malignant cells and to have diagnostic tissue (Repeat: 48.3% malignant; 20.2% benign; 1.1% nondiagnostic; Initial: 25.8% malignant; 23.6% benign; 14.6% nondiagnostic). The most common histology difference after repeat biopsy was a change in malignant diagnosis (38.2% [34/89]). CONCLUSION: Repeat percutaneous biopsy within 30 days of the same organ is uncommon (~ 2%), but when indicated, it commonly changes diagnosis and improves diagnostic yield. Repeat biopsy within 30 days is a potential performance measure for radiology procedure services.

CT-measured Cortical Volume Ratio Is an Accurate Alternative to Nuclear Medicine Split Scan Ratio Among Living Kidney Donors.

BACKGROUND: The 125I-iothalamate clearance and 99mTc diethylenetriamine-pentaacetic acid (99mTc-DTPA) split scan nuclear medicine studies are used among living kidney donor candidates to determine measured glomerular filtration rate (mGFR) and split scan ratio (SSR). The computerized tomography-derived cortical volume ratio (CVR) is a novel measurement of split kidney function and can be combined with predonation estimated GFR (eGFR) or mGFR to predict postdonation kidney function. Whether predonation SSR predicts postdonation kidney function better than predonation CVR and whether predonation mGFR provides additional information beyond predonation eGFR are unknown. METHODS: We performed a single-center retrospective analysis of 204 patients who underwent kidney donation between June 2015 and March 2019. The primary outcome was 1-y postdonation eGFR. Model bases were created from a measure of predonation kidney function (mGFR or eGFR) multiplied by the proportion that each nondonated kidney contributed to predonation kidney function (SSR or CVR). Multivariable elastic net regression with 1000 repetitions was used to determine the mean and 95% confidence interval of R2, root mean square error (RMSE), and proportion overprediction ≥15 mL/min/1.73 m2 between models. RESULTS: In validation cohorts, eGFR-CVR models performed best (R2, 0.547; RMSE, 9.2 mL/min/1.73 m2, proportion overprediction 3.1%), whereas mGFR-SSR models performed worst (R2, 0.360; RMSE, 10.9 mL/min/1.73 m2, proportion overprediction 7.2%) (P < 0.001 for all comparisons). CONCLUSIONS: These findings suggest that predonation CVR may serve as an acceptable alternative to SSR during donor evaluation and furthermore, that a model based on CVR and predonation eGFR may be superior to other methods.

Prostate Imaging and Data Reporting System Version 2 as a Radiology Performance Metric: An Analysis of 18 Abdominal Radiologists.

PURPOSE: To determine expected trained provider performance dispersion in Prostate Imaging and Data Reporting System version 2 (PI-RADS v2) positive predictive values (PPVs). METHODS: This single-center quality assurance retrospective cohort study evaluated 5,556 consecutive prostate MRIs performed on 4,593 patients. Studies were prospectively interpreted from October 8, 2016, to July 31, 2020, by 18 subspecialty-trained abdominal radiologists (1-22 years' experience; median MRIs per radiologist: 232, first-to-third quartile range [Q1-Q3]: 128-440; 13 interpreted at least 30 MRIs with a reference standard). Maximum prospectively reported whole-gland PI-RADS v2 score was compared to post-MRI biopsy histopathology obtained within 2 years. The primary outcome was PPV of MRI by provider stratified by maximum whole-gland PI-RADS v2 score. RESULTS: Median provider-level PPVs for the radiologists who interpreted ≥30 MRIs with a reference standard were PI-RADS 3 (22.1%; Q1-Q3: 10.0%-28.6%), PI-RADS 4 (49.2%; Q1-Q3: 41.4%-50.0%), PI-RADS 5 (81.8%; Q1-Q3: 77.1%-84.4%). Overall, the maximum whole-gland PI-RADS v2 score was PI-RADS 1 to 2 (34.6% [1,925]), PI-RADS 3 (8.5% [474]), PI-RADS 4 (21.0% [1,166]), PI-RADS 5 (18.3% [1,018]), no PI-RADS score (17.5% [973]). System-level (all providers) PPVs for maximum PI-RADS v2 scores were 20.0% (95% confidence interval [CI]: 15.7%-24.9%) for PI-RADS 3, 48.5% (95% CI: 44.8%-52.2%) for PI-RADS 4, and 80.1% for PI-RADS 5 (95% CI: 75.7%-83.9%). CONCLUSION: Subspecialty-trained abdominal radiologists with a wide range of experience can obtain consistent positive predictive values for PI-RADS v2 scores of 3 to 5. These data can be used for quality assurance benchmarking.

Characteristics of gadolinium-based contrast media cancellation at the point of care: a 15-month assessment of FDA-inspired medication guides on gadolinium retention.

PURPOSE: To assess the effect of United States Food and Drug Administration (FDA)-inspired patient handouts, regarding gadolinium retention, on the frequency of patient-initiated cancellations of gadolinium-based contrast media (GBCM) at the point of care. METHODS: This is a single center retrospective cohort review of MRI examinations protocolled to receive GBCM but performed without GBCM from October 2017 to January 2019. The study period spans an FDA-inspired safety intervention (December 2017 to May 2018) to provide patients with a handout on gadolinium retention. Examinations were coded according to rationale for GBCM cancellation. Process control charts were created to statistically evaluate trends in GBCM cancellations over time. RESULTS: From October 2017 to January 2019, GBCM was canceled at the point of care for 0.22% (131/58,837; 95% CI 0.19-0.26) of examinations in which GBCM was indicated. This did not significantly vary during the study period. No cancellations (0/131) were due to stated concern for gadolinium retention. However, 38% (50/131; 95% CI 30-47) were canceled due to kidney impairment and 21% (28/131; 95% CI 13-30) were canceled for an unknown reason. CONCLUSION: FDA-inspired handouts informing patients about gadolinium retention did not significantly change the frequency of GBCM cancellation. GBCM cancellations at the point of care remain uncommon.

Intraobserver Variability in Bladder Cancer Treatment Response Assessment With and Without Computerized Decision Support.

We evaluated the intraobserver variability of physicians aided by a computerized decision-support system for treatment response assessment (CDSS-T) to identify patients who show complete response to neoadjuvant chemotherapy for bladder cancer, and the effects of the intraobserver variability on physicians' assessment accuracy. A CDSS-T tool was developed that uses a combination of deep learning neural network and radiomic features from computed tomography (CT) scans to detect bladder cancers that have fully responded to neoadjuvant treatment. Pre- and postchemotherapy CT scans of 157 bladder cancers from 123 patients were collected. In a multireader, multicase observer study, physician-observers estimated the likelihood of pathologic T0 disease by viewing paired pre/posttreatment CT scans placed side by side on an in-house-developed graphical user interface. Five abdominal radiologists, 4 diagnostic radiology residents, 2 oncologists, and 1 urologist participated as observers. They first provided an estimate without CDSS-T and then with CDSS-T. A subset of cases was evaluated twice to study the intraobserver variability and its effects on observer consistency. The mean areas under the curves for assessment of pathologic T0 disease were 0.85 for CDSS-T alone, 0.76 for physicians without CDSS-T and improved to 0.80 for physicians with CDSS-T (P = .001) in the original evaluation, and 0.78 for physicians without CDSS-T and improved to 0.81 for physicians with CDSS-T (P = .010) in the repeated evaluation. The intraobserver variability was significantly reduced with CDSS-T (P < .0001). The CDSS-T can significantly reduce physicians' variability and improve their accuracy for identifying complete response of muscle-invasive bladder cancer to neoadjuvant chemotherapy.