Importance of measurement site on assessment of lesion-specific ischemia and diagnostic performance by coronary computed tomography Angiography-Derived Fractional Flow Reserve

BackgroundValues of fractional flow reserve (FFR_CT) by coronary computed tomography angiography (CTA) decline from the ostium to the terminal vessel, irrespective of stenosis severity. The purpose of this study is to determine if the site of measurement of FFR_CT impacts assessment of ischemia and its diagnostic performance relative to invasive FFR (FFR_INV).Methods1484 patients underwent FFR_CT; 1910 vessels were stratified by stenosis severity (normal; <25%, 25–50%, 50–70%, and >70% stenosis). The rates of positive FFR_CT (≤0.8) were determined by measuring FFR_CT from the terminal vessel and from distal-to-the-lesion. Reclassification rates from positive to negative FFR_CT were calculated. Diagnostic performance of FFR_CT relative to FFR_INV was evaluated in 182 vessels using linear regression, Bland Altman analysis, and receiver operating characteristic (ROC) curves.ResultsPositive FFR_CT was identified in 24.9% of vessels using terminal vessel FFR_CT and 10.1% using FFR_CT distal-to-the-lesion (p ?< ?0.001). FFR_CT obtained distal-to-the-lesion resulted in reclassification of 59.6% of positive terminal FFR_CT to negative FFR_CT. Relative to FFR_INV, there were improvements in specificity (50% to 86%, p ?< ?0.001), diagnostic accuracy (65% to 88%, p ?< ?0.001), positive predictive value (50% to 78%, p ?< ?0.001), and area-under-the-curve (AUC, 0.83 to 0.91, p ?< ?0.001) when FFR_CT was measured distal-to-the-lesion.ConclusionFFR_CT values from the terminal vessel should not be used to assess lesion-specific ischemia due to high rates of false positive results. FFR_CT measured distal-to-the-lesion improves the diagnostic performance of FFR_CT relative to FFR_INV, ensures that FFR_CT values are due to lesion-specific ischemia, and could reduce the rate of unnecessary invasive procedures.     

Age,period, and cohort patterns in the epidemiology of suicide attempts among sexual minorities in the United States and Canada: detection of a second peak in middle adulthood

Purpose

Sexual minority adults experience fivefold greater risk of suicide attempt, as compared with heterosexuals. Establishing age-specific epidemiological patterns of suicide is a prerequisite to planning interventions to redress the sexual orientation suicide inequity, and such patterns must be carefully interpreted in light of correlated period and cohort effects. We, therefore, combined US and Canadian data (1985–2017) from primary (two pooled multi-year national surveys, N = 15,477 and N = 126,463) and secondary (published, meta-analytic, N = 122,966) sources to separately estimate age, period, and cohort trends in self-reported suicide attempts among sexual minorities.

Methods

Age- and gender-stratified cross-sectional data were used to infer age and cohort effects. Age-collapsed meta-analyzed data were used to infer period effects among sexual minorities of all genders.

Results

We identified a bimodal age distribution in recent suicide attempts for sexual minorities across genders, though more pronounced among sexual minority men: one peak in adolescence (18–20 years of age for both genders) and one peak nearing mid-life (30–35 years of age for men; 35–40 years of age for women). This pattern was also apparent using recall data within birth cohorts of sexual minority men, suggesting it is not an artifact of birth cohort effects. Finally, we observed decreasing trends in lifetime suicide attempt prevalence estimates for both sexual minorities and heterosexuals, though these decreases did not affect the magnitude of the sexual orientation disparity.

Conclusion

In the context of exclusively adolescent-focused suicide prevention interventions for sexual minorities, tailored suicide prevention for sexual minority adults should be pursued throughout the life course.

     

Characterization of the orientation and isometry of Humphrey's ligament

Objectives/purposeThe purpose of this study was to examine the effect of flexion angle on isometry and fiber obliquity of the anterior meniscofemoral ligament (Humphrey's ligament (HL)).MethodsFollowing a medial parapatellar arthrotomy on 7 fresh frozen cadavers, the insertion points of the anterolateral (AL) and posteromedial (PM) bundles of the PCL, and HL were identified. Using a 9 mm circular software tool, virtual fibers were created. Within each virtual graft, a central fiber was calculated and used to generate anisometry profiles for the AL and PM bundles and HL at flexion angles of 0°, 30°, 60°, 90°, and 120°. Previously validated computer navigation software was used to re-create three dimensional bundles to measure fiber obliquity in the sagittal, frontal, and axial planes.ResultsHL length increased with knee flexion from 0 to 120°, and underwent similar length changes as the PCL bundles. In full extension and at 90°, the average length of the PM and AL bundles were not statistically different (p = 0.13 and p = 0.85 respectively). From 0 to 120°, the PM bundle was the most isometric, but the anisometry profile was statistically similar to the AL bundle and HL. In general, HL and the PM bundle had similar graphic trends in terms of fiber obliquity in all planes.ConclusionsUsing computer navigation, we have demonstrated that HL has similar isometry profiles as the PM and AL bundles of the PCL, and “mirrored” the obliquity of the PM bundle in all planes throughout flexion to 120°.     

The Composite Severity Score for Lumbar Spine MRI: a Metric of Cumulative Degenerative Disease Predicts Time Spent on Interpretation and Reporting

Conventional measures of radiologist efficiency, such as the relative value unit, fail to account for variations in the complexity and difficulty of a given study. For lumbar spine MRI (LMRI), an ideal performance metric should account for the global severity of lumbar degenerative disease (LSDD) which may influence reporting time (RT), thereby affecting clinical productivity. This study aims to derive a global LSDD metric and estimate its effect on RT. A 10-year archive of LMRI reports comprising 13,388 exams was reviewed. Objective reporting timestamps were used to calculate RT. A natural language processing (NLP) tool was used to extract radiologist-assigned stenosis severity using a 6-point scale (0?=?“normal” to 5?=?“severe”) at each lumbar level. The composite severity score (CSS) was calculated as the sum of each of 18 stenosis grades. The predictive values of CSS, sex, age, radiologist identity, and referring service on RT were examined with multiple regression models. The NLP tool accurately classified LSDD in 94.8% of cases in a validation set. The CSS increased with patient age and differed between men and women. In a univariable model, CSS was a significant predictor of mean RT (R²?=?0.38, p?<?0.001) and independent predictor of mean RT (p?<?0.001) controlling for patient sex, patient age, service location, and interpreting radiologist. The predictive strength of CSS was stronger for the low CSS range (CSS?=?0–25, R²?=?0.83, p?<?0.001) compared to higher CSS values (CSS?>?25, R²?=?0.15, p?=?0.05). Individual radiologist study volume was negatively correlated with mean RT (Pearson’s R?=????0.35, p?<?0.001). The composite severity score predicts radiologist reporting efficiency in LMRI, providing a quantitative measure of case complexity which may be useful for workflow planning and performance evaluation.

     

Mapping Pathways by Which Genetic Risk Influences Adolescent Externalizing Behavior: The Interplay Between Externalizing Polygenic Risk Scores,Parental Knowledge,and Peer Substance Use

Genetic predispositions and environmental influences both play an important role in adolescent externalizing behavior; however, they are not always independent. To elucidate gene–environment interplay, we examined the interrelationships between externalizing polygenic risk scores, parental knowledge, and peer substance use in impacting adolescent externalizing behavior across two time-points in a high-risk longitudinal sample of 1,200 adolescents (764 European and 436 African ancestry; M_age = 12.99) from the Collaborative Study on the Genetics of Alcoholism. Results from multivariate path analysis indicated that externalizing polygenic scores were directly associated with adolescent externalizing behavior but also indirectly via peer substance use, in the European ancestry sample. No significant polygenic association nor indirect effects of genetic risk were observed in the African ancestry group, likely due to more limited power. Our findings underscore the importance of gene–environment interplay and suggest peer substance use may be a mechanism through which genetic risk influences adolescent externalizing behavior.

     

The Radiology Resident as Teaching Consultant: An Innovative Peer-to-Peer Teaching Consultation Service to Strengthen Relationships With Referring Colleagues in the Era of Imaging 3.0

BackgroundThe American College of Radiology Imaging 3.0 paradigm emphasizes the need for radiologists to serve as imaging consultants to their referring colleagues. However, outside the reading room, teaching interactions between radiology and nonradiology residents are limited. Internal Medicine Morning Report (IMMR) is a resident-run educational program widely employed by internal medicine (IM) residencies. Although medical imaging is regularly discussed in IMMR, radiology residents are not typically involved in case preparation. We aimed to develop a peer-to-peer imaging teaching consultation service (TCS) incorporated into the well-established structure of IMMR. By creating illustrative, “dynamic” teaching slides for use at these conferences, we sought to provide salient radiology teaching material, demystify jargon, discuss appropriate imaging use, and review relevant anatomy. We hypothesized that TCS could improve the quality of IMMR as perceived by the IM presenter.MethodsTCS was piloted over a 7-month period. Each referred case was reviewed by a senior radiology resident who produced a set of “dynamic” teaching slides for each case. These included patient imaging overlayed with extensive annotations and animations highlighting teaching points, with particular attention to radiologic terminology. Slides were shared with the IM presenter, who could use them for preparation and include the animations in the talk if desired. TCS effectiveness was evaluated with a survey distributed to participating IM residents.ResultsIn the pilot period, 12 TCS requests were received and 10 were performed in collaboration with 6 IM residents. Survey results indicated that most IM residents did not consult radiologists prior to TCS (5/6, 83%). IM residents used the “dynamic” teaching slides to both prepare for and present at IMMR (5/6, 83%). TCS improved IM residents’ perceived ability to engage their audience (6/6, 100%), confidence in teaching radiology material (4/6, 67%), ability to understand radiology reports (4/6, 67%) and appreciation for what radiologists do (6/6, 100%).ConclusionsThe TCS pilot resulted in successful radiology-IM collaboration and improved knowledge and confidence in teaching imaging concepts. Continuous program evaluation will be performed and future work will assess the effect of TCS on radiologist confidence in real-world clinical consultations.