Inter-reader agreement of pancreatic adenocarcinoma resectability assessment with photon counting versus energy integrating detector CT.

PURPOSE: To compare the inter-reader agreement of pancreatic adenocarcinoma resectability assessment at pancreatic protocol photon-counting CT (PCCT) with conventional energy-integrating detector CT (EID-CT). METHODS: A retrospective single institution database search identified all contrast-enhanced pancreatic mass protocol abdominal CT performed at an outpatient facility with both a PCCT and EID-CT from 4/11/2022 to 10/30/2022. Patients without pancreatic adenocarcinoma were excluded. Four fellowship-trained abdominal radiologists, blinded to CT type, independently assessed vascular tumor involvement (uninvolved, abuts ≤ 180°, encases > 180°; celiac, superior mesenteric artery (SMA), common hepatic artery (CHA), superior mesenteric vein (SMV), main portal vein), the presence/absence of metastases, overall tumor resectability (resectable, borderline resectable, locally advanced, metastatic), and diagnostic confidence. Fleiss's kappa was used to calculate inter-reader agreement. CTDIvol was recorded. Radiation dose metrics were compared with a two-sample t-test. A p < .05 indicated statistical significance. RESULTS: 145 patients (71 men, mean[SD] age: 66[9] years) were included. There was substantial inter-reader agreement, for celiac artery, SMA, and SMV involvement at PCCT (kappa = 0.61-0.69) versus moderate agreement at EID-CT (kappa = 0.56-0.59). CHA had substantial inter-reader agreement at both PCCT (kappa = 0.67) and EIDCT (kappa = 0.70). For metastasis identification, radiologists had substantial inter-reader agreement at PCCT (kappa = 0.78) versus moderate agreement at EID-CT (kappa = 0.56). CTDIvol for PCCT and EID-CT were 16.9[7.4]mGy and 29.8[26.6]mGy, respectively (p < .001). CONCLUSION: There was substantial inter-reader agreement for involvement of 4/5 major peripancreatic vessels (celiac artery, SMA, CHA, and SMV) at PCCT compared with 2/5 for EID-CT. PCCT also afforded substantial inter-reader agreement for metastasis detection versus moderate agreement at EID-CT with statistically significant radiation dose reduction.

Reduced Intravenous Contrast Dose Portal Venous Phase Photon-Counting Computed Tomography Compared With Conventional Energy-Integrating Detector Portal Venous Phase Computed Tomography.

OBJECTIVE: The aim of this study was to compare portal venous phase photon-counting CT (PCCT) using 20 cc less than weight-based contrast dosing with energy-integrating detector CT (EID-CT) using weight-based dosing by quantitative and qualitative analysis. METHODS: Fifty adult patients who underwent a reduced intravenous contrast dose portal venous phase PCCT from May 1, 2023, to August 10, 2023, and a prior portal-venous EID-CT with weight-based contrast dosing were retrospectively identified. Hounsfield units (HU) and noise (SD of HU) were obtained from region-of-interest measurements on 70-keV PCCT and EID-CT in 4 hepatic segments, the main and right portal vein, and both paraspinal muscles. Signal-to-noise and contrast-to-noise ratios were computed. Three abdominal radiologists qualitatively assessed overall image quality, hepatic enhancement, and confidence for metastasis identification on 5-point Likert scales. Readers also recorded the presence/absence of hepatic metastases. Quantitative variables were compared with paired t tests, and multiple comparisons were accounted for with a Bonferroni-adjusted α level of .0016. Ordinal logistic regression was used to evaluate qualitative assessments. Interreader agreement for hepatic metastases was calculated using Fleiss' κ. RESULTS: Fifty patients (32 women; mean [SD] age, 64 [13] years) were included. There was no significant difference in hepatic HU, portal vein HU, noise, and signal-to-noise or contrast-to-noise ratio between reduced contrast dose portal venous phase PCCT versus EID-CT (all Ps > 0.0016). Image quality, degree of hepatic enhancement, and confidence for metastasis identification were not different for reduced dose PCCT 70-keV images and EID-CT (P = 0.06-0.69). κ Value for metastasis identification was 0.86 (95% confidence interval, 0.70-1.00) with PCCT and 0.78 (95% confidence interval, 0.59-0.98) with EID-CT. CONCLUSION: Reduced intravenous contrast portal venous phase PCCT 70-keV images had similar attenuation and image quality as EID-CT with weight-based dosing. Metastases were identified with near-perfect agreement in reduced dose PCCT 70-keV images.

The Impact of Virtual Residency Interviews on the Geographic Distribution of Integrated Interventional and Diagnostic Radiology Residency Matches.

PURPOSE: To characterize how the adoption of virtual residency interviews (2020-2021 cycle) has impacted the geographic distribution of radiology resident matches. METHODS: University-based interventional (IR) and diagnostic radiology (DR) residency programs from 2017 to 2021 were identified using a national residency database (FRIEDA). Public applicant data were obtained from official residency program websites. Medical schools and residency programs were categorized by US census regions. Geographic applicant distribution before and after the initiation of virtual interviews was statistically assessed using Chi-square tests. The effect of virtual interviews on the probability of matching within the same geographic region as one's medical school was evaluated with multivariate logistic regression. RESULTS: 4358 radiology residents (88% diagnostic, 12% interventional) matched at 102 radiology programs during the study period. 71% (n = 3115 residents) had data available for analysis. 56.3% of DR and 49.3% of IR residents matched in the same geographic region as their medical school. The geographic distribution of applicants who matched at Southern IR residency programs significantly changed after implementation of virtual interviews (p < 0.0001). Virtual interviews did not increase the odds of matching in the same region as one's medical school for IR (OR 1.11, p = 0.08) or DR (OR 1.01, p = 0.58) applicants. Top-20 ranked DR programs had lower odds of in-region matches (OR 0.87, p < 0.001). CONCLUSION: With few exceptions, shifting to virtual residency interviews did not significantly affect the geographic distribution of IR or DR residency matches. Top-ranked DR programs match more regionally diverse applicants.

Pulmonary Cryoablation Outcomes in Octogenarians and Nonagenarians with Primary Lung Cancer.

PURPOSE: To characterize the effectiveness, safety, and length of stay (LOS) associated with pulmonary cryoablation for management of primary lung malignancies in patients aged ≥80 years. MATERIALS AND METHODS: A retrospective single-center database was compiled of all consecutive patients aged ≥80 years who underwent percutaneous computed tomography-guided cryoablation using modified triple-freeze protocol (1-3 ablation probes) for Stage IA-IIB primary lung malignancies between March 2017 and March 2020 (n = 19; 53% women; mean age, 85 years ± 3.5; range, 80-94 years). Follow-up imaging was assessed for local recurrence. Adverse events and LOS were recorded from chart review. Kaplan-Meier analysis was performed to assess both overall and local recurrence-free survival. RESULTS: Mean patient follow-up period was 21.6 months ± 10.8, and mean imaging follow-up period was 19.2 months ± 9.6. Overall survival at 3 years was 94% (95% CI, 81%-100%). Local recurrence-free survival was 100% throughout the imaging follow-up period. Intraprocedural pneumothorax occurred in 37% (7 of 19) of patients; pneumothorax risk was significantly associated with increased tumor distance from pleura (odds ratio, 1.2; P = .018). Sixty-three percent (12 of 19) of patients were discharged on the day of the procedure, with a mean LOS of 7.7 hours ± 1.6, whereas 37% of patients required overnight observation (2 of 19) or admission (5 of 19), with a mean LOS of 48.1 hours ± 19.4. Overall LOS for all patients was 22.6 hours ± 22.9. CONCLUSIONS: Percutaneous cryoablation of primary pulmonary malignancies can be performed in select octogenarians and nonagenarians with high 3-year overall and recurrence-free survival. Despite nonnegligible risk of pneumothorax, most patients are discharged on the day of the procedure.

Genicular artery embolization for treatment of knee osteoarthritis pain: Systematic review and meta-analysis.

Objective: Genicular artery embolization (GAE) is a novel, minimally invasive procedure for treatment of knee osteoarthritis (OA). This meta-analysis investigated the safety and effectiveness of this procedure. Design: Outcomes of this systematic review with meta-analysis were technical success, knee pain visual analog scale (VAS; 0-100 scale), WOMAC Total Score (0-100 scale), retreatment rate, and adverse events. Continuous outcomes were calculated as the weighted mean difference (WMD) versus baseline. Minimal clinically important difference (MCID) and substantial clinical benefit (SCB) rates were estimated in Monte Carlo simulations. Rates of total knee replacement and repeat GAE were calculated using life-table methods. Results: In 10 groups (9 studies; 270 patients; 339 knees), GAE technical success was 99.7%. Over 12 months, the WMD ranged from -34 to -39 at each follow-up for VAS score and -28 to -34 for WOMAC Total score (all p â€‹< â€‹0.001). At 12 months, 78% met the MCID for VAS score; 92% met the MCID for WOMAC Total score, and 78% met the SCB for WOMAC Total score. Higher baseline knee pain severity was associated with greater improvements in knee pain. Over 2 years, 5.2% of patients underwent total knee replacement and 8.3% received repeat GAE. Adverse events were minor, with transient skin discoloration as the most common (11.6%). Conclusions: Limited evidence suggests that GAE is a safe procedure that confers improvement in knee OA symptoms at established MCID thresholds. Patients with greater knee pain severity may be more responsive to GAE.

Predictors of need for endovascular intervention in hepatic trauma.

PURPOSE: Non-operative management of hepatic trauma with adjunctive hepatic arterial embolization (HAE) is widely accepted. Despite careful patient selection utilizing CTA, a substantial proportion of angiograms are negative for arterial injury and no HAE is performed. This study aims to determine which CT imaging findings and clinical factors are associated with the presence of active extravasation on subsequent angiography in patients with hepatic trauma. MATERIALS AND METHODS: The charts of 243 adults who presented with abdominal trauma and underwent abdominal CTA followed by conventional angiography were retrospectively reviewed. Of these patients, 49 had hepatic injuries on CTA. Hepatic injuries were graded using the American association for the surgery of trauma (AAST) CT classification, and CT images were assessed for active contrast extravasation, arterial pseudoaneurysm, sentinel clot, hemoperitoneum, laceration in-volving more than 2 segments, and laceration involving specific anatomic landmarks (porta hepatis, hepatic veins, and gallbladder fossa). Medical records were reviewed for pre- and post-angiography blood pressures, hemoglobin levels, and transfusion requirements. Angiographic images and reports were reviewed for hepatic arterial injury and performance of HAE. RESULTS: In multivariate analysis, AAST hepatic injury grade was significantly associated with increased odds of HAE (Odds ratio: 2.5, 95% CI 1.1, 7.1, p = 0.049). Univariate analyses demonstrated no significant association between CT liver injury grade, CT characteristics of liver injury, or pre-angiographic clinical data with need for HAE. CONCLUSION: In patients with hepatic trauma, prediction of need for HAE based on CT findings alone is challenging; such patients require consideration of both clinical factors and imaging findings.

Venous Malformations.

Venous malformations, the most common type of vascular malformation, are slow-flow lesions resulting from disorganized angiogenesis. The International Society for the Study of Vascular Anomalies (ISSVA) classification offers a categorization scheme for venous malformations based on their genetic landscapes and association with congenital overgrowth syndromes. Venous malformations present as congenital lesions and can have broad physiologic and psychosocial sequelae depending on their size, location, growth trajectory, and tissue involvement. Diagnostic evaluation is centered around clinical examination, imaging evaluation with ultrasound and time-resolved magnetic resonance imaging, and genetic testing for more complex malformations. Interventional radiology has emerged as first-line management of venous malformations through endovascular treatment with embolization, while surgery and targeted molecular therapies offer additional therapeutic options. In this review, an updated overview of the genetics and clinical presentation of venous malformations in conjunction with key aspects of diagnostic imaging and treatment are discussed.

Computed Tomography Evaluation of In Vivo Pulmonary Cryoablation Zone Sizes.

PURPOSE: To evaluate ablation zone sizes in patients undergoing pulmonary tumor cryoablation with 14-gauge cryoablation probes. MATERIALS AND METHODS: A single-center retrospective analysis of all consecutive patients who underwent cryoablation of pulmonary tumors with 1 or more 14-gauge probes (August 2017 to June 2020) was performed. Intraprocedural and 1-2-month postprocedural chest computed tomography (CT) scans were evaluated to characterize pulmonary lesions, ice balls, and ablation zones. Single-probe 14-gauge ablation zone volumes were compared with manufacturer reference isotherms and single- and 2-probe ablation zones from a prior investigation of 17-gauge probes. Overall survival and local recurrence-free survival were calculated to 3 years. RESULTS: Forty-seven pulmonary malignancies in 42 patients (women, 50%; mean age, 75.2 years ± 11.5) underwent cryoablation with 1 (n = 35), 2 (n = 10), or 3 (n = 2) cryoablation probes. One- to 2-month follow-up CT images were available for 30 of the 42 patients. The mean cryoablation zone volumes at 1-2 months when 1 (n = 21), 2 (n = 8), and 3 (n = 1) probes were used were 5.0 cm3 ± 2.3, 37.5 cm3 ± 20.5, and 28.4 cm3, respectively. The mean single-probe follow-up ablation zone volume was larger than that previously reported for 17-gauge probes (3.0 cm3 ± 0.3) (P < .001) but smaller than manufacturer-reported isotherms (11.6 cm3 for -40 °C isotherm) and the 2-probe ablation zone volume with 17-gauge devices (12.9 cm3 ± 2.4) (for all, P < 001). The 3-year overall survival and local recurrence-free survival were 69% (95% confidence interval [CI], 53%-89%) and 87% (95% CI, 74%-100%), respectively. CONCLUSIONS: Fourteen-gauge probes generate larger ablation volumes than those generated by 17-gauge probes. Manufacturer-reported isotherms are significantly larger than actual cryoablation zones. Cryoablation can attain low rates of local recurrence.

Radioembolization in the Setting of Systemic Therapies.

90 Yttrium (Y90) radioembolization has been shown to improve outcomes for primary and metastatic liver cancers, but there is limited understanding of the optimal timing and safety of combining systemic therapies with Y90 treatment. Both therapeutic effects and toxicities could be synergistic depending on the timing and dosing of different coadministration paradigms. In particular, patients with liver-only or liver-dominant metastatic disease progression are often on systemic therapy when referred to interventional radiology for consideration of Y90 treatment. Interventional radiologists are frequently asked to offer insight into whether or not to hold systemic therapy, and for how long, prior to and following transarterial therapy. This study reviews the current evidence regarding the timing and safety of systemic therapy with Y90 treatment for hepatocellular carcinoma, metastatic colorectal carcinoma, intrahepatic cholangiocarcinoma, metastatic neuroendocrine tumors, and other hepatic metastases. A particular focus is placed on the timing, dosing, and toxicities of combined therapy.

Comparison of Anticoagulation Regimens Following Stent Placement for Nonthrombotic Lower Extremity Venous Disease.

PURPOSE: To determine whether subtherapeutic anticoagulation regimens are noninferior to therapeutic anticoagulation regimens following stent placement for nonthrombotic lower extremity venous disease. MATERIALS AND METHODS: Fifty-one consecutive patients (88% women; mean age, 44 years) who underwent stent placement for nonthrombotic lower extremity venous disease between 2002 and 2016 were retrospectively identified. The patients were divided into 2 cohorts: those who received prophylactic enoxaparin or no anticoagulation (subtherapeutic) after the procedure and those who received therapeutic doses of anticoagulation with enoxaparin, warfarin, and/or rivaroxaban (therapeutic) after the procedure. Baseline demographic characteristics, procedure characteristics, and outcomes were compared between the 2 groups using the Student t test, Fisher exact test, and χ2 test. The subtherapeutic and therapeutic anticoagulation groups did not differ significantly in the baseline demographic characteristics (eg, sex, race, and age) or procedure characteristics (eg, number of stents placed, stent brand, stent diameter, etc). RESULTS: The mean clinical follow-up time was 4.4 years (range, 0-16.3 years). There were no thrombotic adverse events or luminal obstructions due to in-stent restenosis in either group. There were 5 minor bleeding adverse effects in the therapeutic group and no bleeding adverse effects in the subtherapeutic group (P = .051). There were no statistically significant differences in subjective symptom improvement (P = .75). CONCLUSIONS: In this retrospective cohort, the subtherapeutic and therapeutic anticoagulation regimens produced equivalent outcomes in terms of adverse event rates, reintervention rates, and symptomatic improvement, suggesting that therapeutic doses of anticoagulation do not improve outcomes compared with subtherapeutic anticoagulation regimens following nonthrombotic venous stent placement.

Diagnostic performance of lower extremity Doppler ultrasound in detecting iliocaval obstruction.

OBJECTIVE: To retrospectively evaluate the performance of two commonly used Doppler ultrasound parameters, namely, venous flow phasicity and response to Valsalva maneuver, in detecting iliocaval obstruction. METHODS: All imaging studies of patients seen by interventional radiology for lower extremity venous disease at a single institution from 1996 to 2018 were retrospectively identified. Lower extremity ultrasounds with a concurrent magnetic resonance, computed tomography, or conventional venogram performed within the next 7 days, which served as gold standard, were further identified (n = 192 examinations, including 313 limbs). Iliocaval obstruction were assessed by two ultrasound criteria: (1) nonphasic flow and/or (2) nonresponsive flow to Valsalva in the common femoral vein. The sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) for diagnosing iliocaval obstruction were calculated for each ultrasound criterion, and also for when the two criteria were assessed jointly. RESULTS: Of the 313 limbs assessed for venous flow phasicity, 133 (42.5%) had an iliocaval obstruction confirmed on subsequent venography. Nonphasic flow demonstrated a sensitivity of 69.2%, specificity of 82.8%, NPV of 78.4%, and PPV of 74.8% for diagnosing iliocaval obstruction. Of the 212 limbs assessed for Valsalva response, 88 (41.5%) had a confirmed iliocaval obstruction. Nonresponsive flow to Valsalva demonstrated a sensitivity of 13.6%, specificity of 97.6%, NPV of 61.6%, and PPV of 80.0% for diagnosing iliocaval obstruction. Joint assessment using phasicity and Valsalva criteria demonstrated a sensitivity of 68.2%, specificity of 87.2%, NPV of 79.6%, and PPV of 78.9%. CONCLUSIONS: In this tertiary care setting, Doppler ultrasound examination was not a reliable diagnostic tool for detecting iliocaval obstruction.

Analysis of patent, unstented lower extremity vein segment diameters in 266 patients with venous disease.

OBJECTIVE: The objective of this study was to characterize the average maximum diameters of widely patent lower extremity vein segments in patients with underlying venous disease and the demographic factors that affect these diameters. METHODS: Maximum axial diameters of each deep vein segment from the diaphragm to the knee were measured from computed tomography venography studies for all patients who underwent venous stent placement during a 20-year period at a single quaternary venous referral institution. Limbs containing only widely patent, unstented vein segments without variant anatomy were identified for inclusion. The final analysis involved diameter measurements from 870 imaging studies of 266 patients. Multivariate linear regression was used to identify factors associated with vein segment diameters. RESULTS: Average vein segment diameters ranged from 7.8 mm for the left and right femoral veins to 27.9 mm for the long axis of the suprarenal inferior vena cava. Multivariate linear regression demonstrated that women had larger IVC, common iliac vein, and external iliac vein diameters, whereas men had larger common femoral veins. Laterality, height, weight, and sex also had statistically significant associations with the diameters of select vein segments. CONCLUSIONS: This study provides an estimate of the average diameters of widely patent deep vein segments in the lower extremities from the diaphragm to the knees in patients with underlying venous disease and characterizes covariates that significantly affect vein diameter. These findings may help interventionalists better select devices for endovascular intervention.

Automated Quantitative Imaging Measurements of Disease Severity in Patients with Nonthrombotic Iliac Vein Compression.

PURPOSE: An automated segmentation technique (AST) for computed tomography (CT) venography was developed to quantify measures of disease severity before and after stent placement in patients with left-sided nonthrombotic iliac vein compression. MATERIALS AND METHODS: Twenty-one patients with left-sided nonthrombotic iliac vein compression who underwent venous stent placement were retrospectively identified. Pre- and poststent CT venography studies were quantitatively analyzed using an AST to determine leg volume, skin thickness, and water content of fat. These measures were compared between diseased and nondiseased limbs and between pre- and poststent images, using patients as their own controls. Additionally, patients with and without postthrombotic lesions were compared. RESULTS: The AST detected significantly increased leg volume (12,437 cm3 vs 10,748 cm3, P < .0001), skin thickness (0.531 cm vs 0.508 cm, P < .0001), and water content of fat (8.2% vs 5.0%, P < .0001) in diseased left limbs compared with the contralateral nondiseased limbs, on prestent imaging. After stent placement in the left leg, there was a significant decrease in the water content of fat in the right (4.9% vs 2.7%, P < .0001) and left (8.2% vs 3.2%, P < .0001) legs. There were no significant changes in leg volume or skin thickness in either leg after stent placement. There were no significant differences between patients with or without postthrombotic lesions in their poststent improvement across the 3 measures of disease severity. CONCLUSIONS: ASTs can be used to quantify measures of disease severity and postintervention changes on CT venography for patients with lower extremity venous disease. Further investigation may clarify the clinical benefit of such technologies.

Lower Extremity Venous Stent Placement: A Large Retrospective Single-Center Analysis.

PURPOSE: To study short-term and long-term outcomes of lower extremity venous stents placed at a single center and to characterize changes in vein diameter achieved by stent placement. MATERIALS AND METHODS: A database of all patients who received lower extremity venous stents between 1996 and 2018 revealed 1,094 stents were placed in 406 patients (172 men, 234 women; median age, 49 y) in 513 limbs, including patients with iliocaval stents (9.4% acute thrombosis, 65.3% chronic thrombosis, 25.3% nonthrombotic lesions). Primary, primary assisted, and secondary patency rates were assessed for lower extremity venous stents at 1, 3, and 5 years using Kaplan-Meier analyses and summary statistics. Subset analyses and Cox regression were performed to identify risk factors for patency loss. Vein diameters and Villalta scores before and up to 12 months after stent placement were compared. Complication and mortality rates were calculated. RESULTS: Primary, primary assisted, and secondary patency rates at 5 years were 57.3%, 77.2%, and 80.9% by Kaplan-Meier methods and 78.6%, 90.3%, and 92.8% by summary statistics. Median follow-up was 199 days (interquartile range, 35.2-712.0 d). Patency rates for the subset of patients (n = 46) with ≥ 5 years of follow-up (mean ± SD 9.1 y ± 3.4) were nearly identical to cohort patency rates at 5 years. Patients with inferior vena cava stent placement (hazard ratio 2.11, P < .0001) or acute thrombosis (hazard ratio 3.65, P < .0001) during the index procedure had significantly increased risk of losing primary patency status. Vein diameters were significantly greater after stent placement. There were no instances of stent fracture, migration, or structural deformities. In patients with chronic deep vein thrombosis, Villalta scores significantly decreased after stent placement (from 15.7 to 7.4, P < .0001). Perioperative mortality was < 1%, and major perioperative complication rate was 3.7%. CONCLUSIONS: Cavo-ilio-femoral stent placement for venous occlusive disease achieves improvement of vein disease severity scores, increase in treated vein diameters, and satisfactory long-term patency rates.

Inferior Vena Cava Atresia: Characterisation of Risk Factors, Treatment, and Outcomes.

PURPOSE: To characterise (1) the risk factors associated with inferior vena cava (IVC) atresia, (2) the radiographic and clinical presentations of deep vein thrombosis (DVT) in patients with IVC atresia, and (3) the treatment and outcome of DVT in patients with IVC atresia. METHODS: The electronic medical record was systematically reviewed for thrombotic risk factors in patients who presented with lower-extremity DVT (n = 409) at a single centre between 1996 and 2017. Patients with IVC atresia were identified based on imaging and chart review. Differences in demographics and thrombotic risk factors between patients with and without IVC atresia were statistically assessed. Extent and chronicity of DVT on imaging, clinical presentation, treatment, and outcomes were evaluated for all patients with IVC atresia. RESULTS: 4.2% of DVT patients (17/409) were found to have IVC atresia; mean age at diagnosis was 25.5 ± 9.4 years. The rate of heritable thrombophilia was significantly higher in patients with IVC atresia compared to patients without IVC atresia (52.9% vs. 17.9%, p < 0.0001). There were bilateral DVT in 70.6% of IVC atresia patients; DVT was chronic in 41.2% and acute on chronic in 58.8%. Pre-intervention Villalta scores were 13.9 ± 9.8 in the left limb and 8.5 ± 7.0 in the right limb. DVT in IVC atresia patients was typically treated with catheter-directed thrombolysis followed by stent placement, achieving complete or partial symptom resolution in 78.6% of cases. CONCLUSION: Thrombotic risk factors such as heritable thrombophilia are associated with IVC atresia. IVC atresia patients can experience high burdens of lower-extremity thrombotic disease at a young age which benefit from endovascular treatment. LEVEL OF EVIDENCE: Level 4.

Toward Data-Driven Learning Healthcare Systems in Interventional Radiology: Implementation to Evaluate Venous Stent Patency.

We developed a code and data-driven system (learning healthcare system) for gleaning actionable clinical insight from interventional radiology (IR) data. To this end, we constructed a workflow for the collection, processing and analysis of electronic health record (EHR), imaging, and cancer registry data for a cohort of interventional radiology patients seen in the IR Clinic at our institution over a more than 20-year period. As part of this pipeline, we created a database in REDCap (VITAL) to store raw data, as collected by a team of clinical investigators and the Data Coordinating Center at our university. We developed a single, universal pre-processing codebank for our VITAL data in R; in addition, we also wrote widely extendable and easily modifiable analysis code in R that presents results from summary statistics, statistical tests, visualizations, Kaplan-Meier analyses, and Cox proportional hazard modeling, among other analysis techniques. We present our findings for a test case of supra versus infra-inguinal ligament stenting. The developed pre-processing and analysis pipelines were memory and speed-efficient, with both pipelines running in less than 2 min. Three different supra-inguinal ligament veins had a statistically significant improvement in vein diameters post-stenting versus pre-stenting, while no infra-inguinal ligament veins had a statistically significant improvement (due either to an insufficient sample size or a non-significant p value). However, infra-inguinal ligament stenting was not associated with worse restenosis or patency outcomes in either a univariate (summary-statistics and Kaplan-Meier based) or multivariate (Cox proportional hazard model based) analysis.

Correction: Evaluating strategies for control of tuberculosis in prisons and prevention of spillover into communities: An observational and modeling study from Brazil.

[This corrects the article DOI: 10.1371/journal.pmed.1002737.].

Evaluating strategies for control of tuberculosis in prisons and prevention of spillover into communities: An observational and modeling study from Brazil.

BACKGROUND: It has been hypothesized that prisons serve as amplifiers of general tuberculosis (TB) epidemics, but there is a paucity of data on this phenomenon and the potential population-level effects of prison-focused interventions. This study (1) quantifies the TB risk for prisoners as they traverse incarceration and release, (2) mathematically models the impact of prison-based interventions on TB burden in the general population, and (3) generalizes this model to a wide range of epidemiological contexts. METHODS AND FINDINGS: We obtained individual-level incarceration data for all inmates (n = 42,925) and all reported TB cases (n = 5,643) in the Brazilian state of Mato Grosso do Sul from 2007 through 2013. We matched individuals between prisoner and TB databases and estimated the incidence of TB from the time of incarceration and the time of prison release using Cox proportional hazards models. We identified 130 new TB cases diagnosed during incarceration and 170 among individuals released from prison. During imprisonment, TB rates increased from 111 cases per 100,000 person-years at entry to a maximum of 1,303 per 100,000 person-years at 5.2 years. At release, TB incidence was 229 per 100,000 person-years, which declined to 42 per 100,000 person-years (the average TB incidence in Brazil) after 7 years. We used these data to populate a compartmental model of TB transmission and incarceration to evaluate the effects of various prison-based interventions on the incidence of TB among prisoners and the general population. Annual mass TB screening within Brazilian prisons would reduce TB incidence in prisons by 47.4% (95% Bayesian credible interval [BCI], 44.4%-52.5%) and in the general population by 19.4% (95% BCI 17.9%-24.2%). A generalized model demonstrates that prison-based interventions would have maximum effectiveness in reducing community incidence in populations with a high concentration of TB in prisons and greater degrees of mixing between ex-prisoners and community members. Study limitations include our focus on a single Brazilian state and our retrospective use of administrative databases. CONCLUSIONS: Our findings suggest that the prison environment, more so than the prison population itself, drives TB incidence, and targeted interventions within prisons could have a substantial effect on the broader TB epidemic.

Complications, Readmissions, and Revisions for Spine Procedures Performed by Orthopedic Surgeons Versus Neurosurgeons: A Retrospective, Longitudinal Study.

STUDY DESIGN: Retrospective database analysis. OBJECTIVE: To examine the impact of training pathway, either neurosurgical or orthopedic, on complications, readmissions, and revisions in spine surgery. SUMMARY OF BACKGROUND DATA: Training pathway has been shown to have an impact on outcomes in various surgical subspecialties. Although training pathway has not been shown to have a significant impact on spine surgery outcomes in the perioperative period, long-term results are unknown. MATERIALS AND METHODS: A retrospective analysis of 197,682 patients receiving 1 of 3 common spine surgeries [lumbar laminectomy, lumbar fusion, and anterior cervical discectomy and fusion (ACDF)] between 2006 and 2010 was conducted. Patient data were obtained from a large claims database. Postoperative adverse effects, all-cause readmission, revision surgery rates, and intermediary payments in these cohorts of patients were compared between spine surgeons with either neurosurgical or orthopedic backgrounds. RESULTS: Patient demographics, hospital-stay characteristics, and medical comorbidities were similar between neurosurgeons and orthopedic surgeons. The risks of surgical complications, all-cause readmission, and revision surgery were also similar between neurosurgeons and orthopedic surgeons across all procedure types assessed, with several minor exceptions: neurosurgeons had marginally higher odds of any complication for lumbar fusions [odds ratio (OR) 1.14; 95% confidence interval (CI), 1.09-1.20] and ACDFs (OR, 1.09; 95% CI, 1.04-1.15). Neurosurgeons also had slightly higher rates of revision surgery for concurrent lumbar laminectomy with fusion (OR, 1.14; 95% CI, 1.08-1.22), and ACDFs (OR, 1.20; 95% CI, 1.14-1.28). No associations between surgeon type and any particular complication were consistently observed for all procedure groups. There were also no associations between surgeon type and 30-day all-cause readmission. Median total intermediary payments were somewhat higher for neurosurgery patients for all procedure groups assessed. CONCLUSIONS: Few significant associations between surgeon type and patient outcomes exist in the context of spine surgery. Those which do are small and unlikely to be clinically meaningful. LEVEL OF EVIDENCE: Level 3.

Host community perspectives on trainees participating in short-term experiences in global health.

CONTEXT: High-income country (HIC) trainees are undertaking global health experiences in low- and middle-income country (LMIC) host communities in increasing numbers. Although the benefits for HIC trainees are well described, the benefits and drawbacks for LMIC host communities are not well captured. OBJECTIVES: This study evaluated the perspectives of supervising physicians and local programme coordinators from LMIC host communities who engaged with HIC trainees in the context of the latter's short-term experiences in global health. METHODS: Thirty-five semi-structured interviews were conducted with LMIC host community collaborators with a US-based, non-profit global health education organisation. Interviews took place in La Paz, Bolivia and New Delhi, India. Interview transcripts were assessed for recurrent themes using thematic analysis. RESULTS: Benefits for hosts included improvements in job satisfaction, local prestige, global connectedness, local networks, leadership skills, resources and sense of efficacy within their communities. Host collaborators called for improvements in HIC trainee attitudes and behaviours, and asked that trainees not make promises they would not fulfil. Findings also provided evidence of a desire for parity between the opportunities afforded to US-based staff and those available to LMIC-based partners. CONCLUSIONS: This study provides important insights into the perspectives of LMIC host community members in the context of short-term experiences in global health for HIC trainees. We hope to inform the behaviour of HIC trainees and institutions with regard to international partnerships and global health activities.