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The cellular source of positive signals that reinvigorate T cells within the tumor microenvironment (TME) for the therapeutic efficacy of programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) blockade has not been clearly defined. We now show that Batf3-lineage dendritic cells (DCs) are essential in this process. Flow cytometric analysis, gene-targeted mice, and blocking antibody studies revealed that 4-1BBL is a major positive co-stimulatory signal provided by these DCs within the TME that translates to CD8+ T cell functional reinvigoration and tumor regression. Immunofluorescence and spatial transcriptomics on human tumor samples revealed clustering of Batf3+ DCs and CD8+ T cells, which correlates with anti-PD-1 efficacy. In addition, proximity to Batf3+ DCs within the TME is associated with CD8+ T cell transcriptional states linked to anti-PD-1 response. Our results demonstrate that Batf3+ DCs within the TME are critical for PD-1/PD-L1 blockade efficacy and indicate a major role for the 4-1BB/4-1BB ligand (4-1BBL) axis during this process. [Display omitted] • DC1s are needed in the TME for PD-1/PD-L1 blockade efficacy • Anti-PD-L1-induced CD8+ T cell reinvigoration in the TME is 4-1BB/4-1BBL dependent • DC1/CD8+ T cell clustering is associated with clinical response to PD-1 blockade • CD8+ T cell proximity to DC1 is associated with transcriptomics linked to treatment response Ziblat et al. demonstrate that Batf3+ dendritic cells (DC1s) are needed within the tumor for efficacy of PD-1/PD-L1 blockade. Mechanistically, they show that DC1s deliver positive signals through 4-1BB/4-1BBL for the reinvigoration of CD8+ T cells once PD-1/PD-L1 is blocked and that DC1-CD8 clustering correlates with anti-PD-1 clinical efficacy. [ABSTRACT FROM AUTHOR]

Objective: Guideline-concordant follow-up of incidental lung nodules (ILNs) is suboptimal. We aimed to improve communication and tracking for follow-up of these common incidental findings detected on imaging examinations.Methods: We implemented a process improvement program for reporting and tracking ILNs at a large urban academic health care system. A multidisciplinary committee designed, tested, and implemented a multipart tracking system in the electronic health record (EHR) that included Fleischner Society management recommendations for each patient. Plan-do-study-act cycles addressed gaps in the follow-up of ILNs, broken into phases of developing and testing components of the conceived EHR toolkit.Results: The program resulted in standardized text macros with discrete categories and recommendations for ILNs, with ability to track each case in a work list within the EHR. The macros incorporated evidence-based guidelines and also input of collaborating clinical referrers in the respective specialty. The ILN macro was used 3,964 times over the first 2 years, increasing from 104 to over 300 uses per month. Usage spread across all subspecialty divisions, with nonthoracic radiologists currently accounting for 80% (56 of 70) of the radiologists using the system and 31% (1,230 of 3,964) of all captured ILNs. When radiologists indicated ILNs as warranting telephone communication to provider offices, completion was documented in 100% of the cases captured in the EHR-embedded tracking report.Conclusion: An EHR-based system for managing incidental nodules enables case tracking with exact recommendations, provider communication, and completion of follow-up testing. Future efforts will target consistent radiologist use of the system and follow-up completion. [ABSTRACT FROM AUTHOR]

Purpose: To develop natural language processing (NLP) to identify incidental lung nodules (ILNs) in radiology reports for assessment of management recommendations.Methods and Materials: We searched the electronic health records for patients who underwent chest CT during 2014 and 2017, before and after implementation of a department-wide dictation macro of the Fleischner Society recommendations. We randomly selected 950 unstructured chest CT reports and reviewed manually for ILNs. An NLP tool was trained and validated against the manually reviewed set, for the task of automated detection of ILNs with exclusion of previously known or definitively benign nodules. For ILNs found in the training and validation sets, we assessed whether reported management recommendations agreed with Fleischner Society guidelines. The guideline concordance of management recommendations was compared between 2014 and 2017.Results: The NLP tool identified ILNs with sensitivity and specificity of 91.1% and 82.2%, respectively, in the validation set. Positive and negative predictive values were 59.7% and 97.0%. In reports of ILNs in the training and validation sets before versus after introduction of a Fleischner reporting macro, there was no difference in the proportion of reports with ILNs (108 of 500 [21.6%] versus 101 of 450 [22.4%]; P = .8), or in the proportion of reports with ILNs containing follow-up recommendations (75 of 108 [69.4%] versus 80 of 101 [79.2%]; P = .2]. Rates of recommendation guideline concordance were not significantly different before and after implementation of the standardized macro (52 of 75 [69.3%] versus 60 of 80 [75.0%]; P = .43).Conclusion: NLP reliably automates identification of ILNs in unstructured reports, pertinent to quality improvement efforts for ILN management. [ABSTRACT FROM AUTHOR]

Purpose: To determine the utility of an automated radiology-pathology feedback tool.Methods: We previously developed a tool that automatically provides radiologists with pathology results related to imaging examinations they interpreted. The tool also allows radiologists to mark the results as concordant or discordant. Five abdominal radiologists prospectively scored their own discordant results related to their previously interpreted abdominal ultrasound, CT, and MR interpretations between August 2017 and June 2018. Radiologists recorded whether they would have followed up on the case if there was no automated alert, reason for the discordance, whether the result required further action, prompted imaging rereview, influenced future interpretations, enhanced teaching files, or inspired a research idea.Results: There were 234 total discordances (range 30-66 per radiologist), and 70.5% (165 of 234) of discordances would not have been manually followed up in the absence of the automated tool. Reasons for discordances included missed findings (10.7%; 25 of 234), misinterpreted findings (29.1%; 68 of 234), possible biopsy sampling error (13.3%; 31 of 234), and limitations of imaging techniques (32.1%; 75/234). In addition, 4.7% (11 of 234) required further radiologist action, including report addenda or discussion with referrer or pathologist, and 93.2% (218 of 234) prompted radiologists to rereview the images. Radiologists reported that they learned from 88% (206 of 234) of discordances, 38.6% (90 of 233) of discordances probably or definitely influenced future interpretations, 55.6% (130 of 234) of discordances prompted the radiologist to add the case to his or her teaching files, and 13.7% (32 of 233) inspired a research idea.Conclusion: Automated pathology feedback provides a valuable opportunity for radiologists across experience levels to learn, increase their skill, and improve patient care. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: To explore downstream costs associated with incidental pulmonary nodules detected on CT.Materials and Methods: The cohort comprised 200 patients with an incidental pulmonary nodule on chest CT. Downstream events (chest CT, PET/CT, office visits, percutaneous biopsy, and wedge resection) were identified from the electronic medical record. The 2017 Fleischner Society Guidelines were used to classify radiologists' recommendations and ordering physician management for the nodules. Downstream costs for nodule management were estimated from national Medicare rates, and average costs were determined.Results: Average downstream cost per nodule was $393. Costs were greater when ordering physicians over-managed relative to radiologist recommendations ($940) vs. when adherent ($637) or under-managing ($166) relative to radiologists recommendations. Costs were also greater when ordering physicians over-managed relative to Fleischner Society guidelines ($860) vs. when under-managing ($208) or adherent ($292) to guidelines. Costs did not vary significantly based on whether or not radiologists recommended follow-up imaging ($167-$397), nor whether radiologists were adherent or under- or over-recommended relative to Fleischner Society guidelines ($313-$444). Costs were also higher in older patients, patients with a smoking history, and larger nodules. Five nodules underwent wedge resection and diagnosed as malignancies. No patient demonstrated recurrence or metastasis. Average cost per diagnosed malignancy was $3090.Conclusion: Downstream costs for incidental pulmonary nodules are highly variable and particularly high when ordering physicians over-manage relative to radiologist recommendations and Fleischner Society guidelines. To reduce unnecessary utilization and cost from over-management, radiologists may need to assume a greater role in partnering with ordering physicians to ensure appropriate, guideline-adherent, and follow-up testing. [ABSTRACT FROM AUTHOR]

Inadequate imaging surveillance has been identified as the most significant contributor to abdominal aortic aneurysm (AAA) rupture. Radiologists can contribute value to patient care and reduce morbidity and mortality related to AAA by incorporating evidence-based management recommendations from the ACR and Society of Vascular Surgery into their report impression. The challenges lie in achieving 100% radiologist compliance to incorporate the recommendations and ensuring that the patient is notified by their provider, the follow-up examination is scheduled, and the patient returns for an imaging test that may be scheduled 3 to 5 years in the future. To address these barriers, radiology quality and informatics leads have harnessed IT solutions to facilitate integration of content, communication of results, and patient follow-up. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: Correlation of imaging studies and reference standard outcomes is a significant challenge in radiology. This study evaluates the effectiveness of a new communication tool by assessing the ability of this system to correctly match the imaging studies to arthroscopy reports and qualitatively assessing radiologist behavior before and after the implementation of this system.Materials and Methods: Using a commercially available communication or educational tool and applying a novel matching rule algorithm, radiology and arthroscopy reports were matched from January 17, 2017 to March 1, 2017 based on anatomy. The interpreting radiologist was presented with email notifications containing the impression of the imaging report and the entire arthroscopy report. Total correlation rate of appropriate report pairings, modality-specific correlation rate, and the anatomy-specific correlation rate were calculated. Radiologists using the system were given a survey.Results: Overall correlation rate for all musculoskeletal imaging was 83.1% (433 or 508). Low correlation was found in fluoroscopic procedures at 74.4%, and the highest correlation was found with ultrasound at 88.4%. Anatomic location varied from 51.6% for spine to 98.8% for hips and pelvis studies. Survey results revealed 87.5% of the respondents reporting being either satisfied or very satisfied with the new communication tool. The survey also revealed that some radiologists reviewed more cases than before.Conclusions: Matching of radiology and arthroscopy reports by anatomy allows for excellent report correlation (83.1%). Automated correlation improves the quality and efficiency of feedback to radiologists, providing important opportunities for learning and improved accuracy. [ABSTRACT FROM AUTHOR]

The existing renal artery aneurysm (RAA) literature is largely composed of reports of patients who underwent intervention. The objective of this study was to review the natural history of RAA. This single-institution retrospective analysis studied all patients with RAA diagnosed by computed tomography imaging between 2015 and 2019, identified by our institutional radiology database. Imaging, demographic, and clinical data were obtained via the electronic medical record. He growth rate was calculated for all patients with radiological follow-up. The cohort consists of 331 patients with 338 RAAs. Most patients were female (61.3%), with 11 (3.3%) of childbearing age. The mean age at diagnosis was 71.5 years (range, 24-99 years). Medical comorbidities included hypertension (73.7%), prior smoking (34.4%), and connective tissue disease (3.9%). Imaging indications included abdominal pain (33.5%), unrelated follow-up (29.6%), and follow-up of an RAA initially diagnosed before the study period (10.7%). Right RAA (61.9%) was more common than left (35.1%); 3% of patients had bilateral RAA. The mean diameter at diagnosis was 12.9 ± 5.9 mm. Size distribution included lesions measuring less than <15 mm (69.9%), 15 to 25 mm (27.1%), and more than 25 mm (3.0%). Anatomic locations included the distal RA (26.7%), renal hilum (42.4%), and mid-RA (13.1%). The majority were true aneurysms (98%); of these, 72.3% were fusiform and 27.7% were saccular. Additional characteristics included calcification (82.2%), thrombus (15.9%), and dissection (0.9%). Associated findings included aortic atherosclerosis (65.6%), additional visceral aneurysms (7.3%), and abdominal aortic aneurysm (5.7%). The mean clinical follow-up among 281 patients was 41.0 ± 24.0 months. The mean radiological follow-up among 137 patients was 26.0 ± 21.4 months. Of these, 43 patients (31.4%) experienced growth, with mean growth rate of 0.23 ± 4.7 mm/year; the remainder remained stable in size. Eight patients eventually underwent intervention (5 endovascular), with the most common indications including size criteria (4/8) and symptom development (3/8). No patient developed rupture. On multivariate analysis, obesity (P =.04) was significantly associated with growth. An initial diameter of more than 25 mm was significantly associated with subsequent intervention (P =.006), but was not significantly associated with growth. Four of five RAAs with an initial diameter 30 mm or greater did not undergo intervention. The mean clinical follow-up for these patients was 24 months; none developed rupture and two remained stable in size. This large institutional cohort found that the majority of RAAs remained stable in size, with few patients meeting indications for repair based on societal guidelines. Current guidelines recommending intervention for asymptomatic aneurysms more than 30 mm seem to be appropriate given their slow progression. [ABSTRACT FROM AUTHOR]

Purpose: Incidental ovarian cysts are frequently detected on imaging. Despite published follow-up consensus statements, there remains variability in radiologist follow-up recommendations and clinician practice patterns. The aim of this study was to evaluate if collaborative ovarian cyst management recommendations and a radiologist decision support tool can improve adherence to follow-up recommendations.Methods: Gynecologic oncologists and abdominal radiologists convened to develop collaborative institutional recommendations for the management of incidental, asymptomatic simple ovarian cysts detected on ultrasound, CT, and MRI. The recommendations were developed by modifying the published consensus recommendations developed by the Society of Radiologists in Ultrasound on the basis of local practice patterns and the experience of the group members. A less formal process involved the circulation of the published consensus recommendations, followed by suggestions for revisions and subsequent consensus, in similar fashion to the ACR Incidental Findings Committee II. The recommendations were developed by building on the published work of experienced groups to provide the authors' medical community with a set of recommendations that could be endorsed by both the Department of Gynecology and the Department of Radiology to provide supportive guidance to the clinicians who manage incidental ovarian cysts. The recommendations were integrated into a radiologist decision support tool accessible from the dictation software. Nine months after tool launch, institutional review board approval was obtained, and radiology reports mentioning ovarian cysts in the prior 34 months were retrospectively reviewed. For cysts detected on ultrasound, adherence rates to Society of Radiologists in Ultrasound recommendations were calculated for examinations before tool launch and compared with adherence rates to the collaborative institutional recommendations after tool launch. Additionally, electronic medical records were reviewed to determine the follow-up chosen by the clinician.Results: For cysts detected on ultrasound, radiologist adherence to recommendations improved from 50% (98 of 197) to 80% (111 of 139) (P < .05). Overmanagement decreased from 34% (67 of 197) to 10% (14 of 139) (P < .05). A recommendation was considered "overmanaged" if the radiologist recommended follow-up when it was not indicated or if the recommended follow-up time was at a shorter interval than indicated. Clinician adherence to radiologist recommendations showed statistically nonsignificant improvement from 49% (36 of 73) to 57% (27 of 47) (P = .5034).Conclusions: Management recommendations developed through collaboration with clinicians may help standardize follow-up of ovarian cysts and reduce overutilization. [ABSTRACT FROM AUTHOR]

A series of cross-linkable membrane materials based on the 6FDA-DAM:DABA (3:2) polyimide with enhanced transport plasticization resistance were synthesized to separate CO 2 from CH 4 . Glycidol was used as a cross-linking agent to modify 6FDA-DAM:DABA (3:2) efficiently and form a transesterification reaction-based cross-linking. The conversion was calculated by solution 1 H NMR. These materials were also characterized via density, glass transition temperature, permeation, and sorption measurements. Pure (CO 2 , CH 4 ) and mixed gas (CO 2 /CH 4 ) permeation was studied on dense films of these materials up to 700 psia (1000 psia) for pure CO 2 (50%:50% CO 2 :CH 4 mixed gas) feed. Compared to the 6FDA-DAM:DABA (3:2) membrane, CO 2 -induced plasticization resistance for cross-linked membranes was enhanced in aggressive feed streams. Under CO 2 feed conditions at 35 °C, plasticization for the 41% glycidol-modified cross-linked membrane was not observed up to approximately 450 psia. Glycidol-induced cross-linking offers an excellent balance of selectivity, permeability, and plasticization resistance. The glycidol-modified 6FDA-DAM:DABA (3:2) is competitive with the earlier reported 1,3-propanediol modified materials. Possible issues such as resistance to contaminants may be final determinants in choice of approach; however, this topic was beyond the scope of the current study. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate all aspects of workflow in a large academic MRI department to determine whether process improvement (PI) efforts could improve key performance indicators (KPIs). Methods: KPI metrics in the investigators'' MR imaging department include daily inpatient backlogs, on-time performance for outpatient examinations, examination volumes, appointment backlogs for pediatric anesthesia cases, and scan duration relative to time allotted for an examination. Over a 3-week period in April 2011, key members of the MR imaging department (including technologists, nurses, schedulers, physicians, and administrators) tracked all aspects of patient flow through the department, from scheduling to examination interpretation. Data were analyzed by the group to determine where PI could improve KPIs. Changes to MRI workflow were subsequently implemented, and KPIs were compared before (January 1, 2011, to April 30, 2011) and after (August 1, 2011, to December 31, 2011) using Mann-Whitney and Fisher''s exact tests. Results: The data analysis done during this PI led to multiple changes in the daily workflow of the MR department. In addition, a new sense of teamwork and empowerment was established within the MR staff. All of the measured KPIs showed statistically significant changes after the reengineering project. Conclusions: Intradepartmental PI efforts can significantly affect KPI metrics within an MR imaging department, making the process more patient centered. In addition, the process allowed significant growth without the need for additional equipment or personnel. [Copyright &y& Elsevier]

Background: Dual-source computed tomography (DSCT) provides diagnostic quality images of the coronary arteries over a wide range of heart rates (HRs). Current dose reduction techniques, including electrocardiographic (ECG) dose modulation and prospective triggering, are optimized for use in patients with relatively slow (<70 beats/min) HRs by limiting radiation dose to the ideal phases of image acquisition. Objective: We evaluated coronary vessel image quality (IQ) at different reconstruction phases in patients with fast HRs (>80 beats/min) to assess potential feasibility of prospective triggering techniques on DSCT. Methods: Patients (n=101) underwent 64-slice DSCT with retrospective ECG-gating without β-blocker premedication. Image reconstructions were performed at 10% R-R wave phase intervals (0%–90%). Patients were grouped by mean HR: group A, <60 beats/min (n=22); group B, 60–80 beats/min (n=57); group C, >80 beats/min (n=22). Coronary artery IQ was assessed by 2 readers in consensus on a 5-point scale. Results: Optimal IQ occurred at 70% phase for all arteries in groups A and B. In group C, optimal IQ occurred at 30% and 40% phases. The 70% phase achieved diagnostic IQ in 97% of group A and 86% of group B. A widened reconstruction window (30%–50%) was necessary for diagnostic IQ in a similar high proportion (84%) of group C. Conclusion: Optimal IQ occurs during late-systolic phases for patients with fast HRs (>80 beats/min). Late-systolic phase prospective triggering is potentially feasible in these patients; however, given the widened reconstruction windows required, a higher radiation dose may be required compared with patients with slower HRs (<80 beats/min). [Copyright &y& Elsevier]

Purpose To explore variation in downstream relative costs associated with ovarian cysts incidentally detected on ultrasound. Methods For 200 consecutive incidental ovarian cysts on ultrasound, ultrasound reports were classified in terms of presence of a radiologist recommendation for additional imaging. All downstream events (imaging, office visits, and surgery) associated with the cysts were identified from the electronic health record. Medical costs associated with these downstream events were estimated using national Medicare rates. Average cost per cyst was stratified by various factors; cost ratios were computed among subgroups. Results Average costs per cyst were 1.9 times greater in postmenopausal than premenopausal women. Relative to when follow-up imaging was neither recommended nor obtained, costs were 1.1 times greater when follow-up imaging was recommended but not obtained, 5.1 times greater when follow-up imaging was both recommended and obtained, and 8.1 times greater when follow-up imaging was obtained despite not being recommended. Costs were 2.5 times greater when the radiologist underrecommended follow-up compared with Society of Radiologists in Ultrasound (SRU) guidelines for management of ovarian cysts, 3.0 times greater when the ordering physician overmanaged compared with the radiologist’s recommendation, as well as 1.7 times and 3.8 times greater when the ordering physician undermanaged and overmanaged compared with SRU guidelines, respectively. Four ovarian neoplasms, although no ovarian malignancy, were diagnosed in the cohort. Conclusion Follow-up costs for incidental ovarian cysts are highly variable based on a range of factors. Radiologist recommendations may contribute to lower costs among patients receiving follow-up imaging. Such recommendations should reflect best practices and support the follow-up that will be of likely greatest value for patient care. [ABSTRACT FROM AUTHOR]

An abstract of the article "Comparison of blood pool and extracellular gadolinium contrast for functional MR evaluation of vascular thoracic outlet syndrome," by Ruth P. Lim., Mary T. Bruno, Andrew B. Rosenkrantz, and colleagues is presented.

Purpose: To identify a cohort of women treated with neoadjuvant chemotherapy and mastectomy for whom postmastectomy radiation therapy (PMRT) may be omitted according to the projected risk of local-regional failure (LRF). Methods and Materials: Seven breast cancer physicians from the University of California cancer centers created 14 hypothetical clinical case scenarios, identified, reviewed, and abstracted the available literature (MEDLINE and Cochrane databases), and formulated evidence tables with endpoints of LRF, disease-free survival, and overall survival. Using the American College of Radiology appropriateness criteria methodology, appropriateness ratings for postmastectomy radiation were assigned for each scenario. Finally, an overall summary risk assessment table was developed. Results: Of 24 sources identified, 23 were retrospective studies from single institutions. Consensus on the appropriateness rating, defined as 80% agreement in a category, was achieved for 86% of the cases. Distinct LRF risk categories emerged. Clinical stage II (T1-2N0-1) patients, aged >40 years, estrogen receptor-positive subtype, with pathologic complete response or 0-3 positive nodes without lymphovascular invasion or extracapsular extension, were identified as having ≤10% risk of LRF without radiation. Limited data support stage IIIA patients with pathologic complete response as being low risk. Conclusions: In the absence of randomized trial results, existing data can be used to guide the use of PMRT in the neoadjuvant chemotherapy setting. Using available studies to inform appropriateness ratings for clinical scenarios, we found a high concordance of treatment recommendations for PMRT and were able to identify a cohort of women with a low risk of LRF without radiation. These low-risk patients will form the basis for future planned studies within the University of California Athena Breast Health Network. [ABSTRACT FROM AUTHOR]

Abstract: Here we review the basic optical spectra of quantum dot molecules. We apply a simple and straightforward model to calculate charge stability regions in vertically coupled double dot molecules that are embedded in a Schottky diode. This model allows us to relate features in the optical spectrum to the diode structure. The underlying concepts allow one to design quantum dot molecules functionalized for optical operations. [Copyright &y& Elsevier]

Diffusion coefficients for water in amorphous poly(ethylene furanoate) (PEF) and poly(ethylene terephthalate) (PET) were studied at 35 °C over the entire water activity range. PEF exhibits a ∼5× reduction in diffusion coefficient averaged over the entire concentration interval compared to PET. Fickian diffusion was observed for water in both polyesters up to ∼0.6 activity, after which the presence of non-Fickian relaxations required treatment using the Berens–Hopfenberg modeling framework. Penetrant plasticization at high activity was found for both PEF and PET, as evidenced by a positive correlation between diffusion coefficient and increasing water concentration. Arrhenius interpretation of diffusion coefficients measured at 15, 25, 35, and 45 °C allowed calculation of the activation energies of diffusion for PEF and PET, which were similar at 47.1 ± 2.8 kJ/mol and 46.4 ± 3.0 kJ/mol, respectively. This study complements prior work pertaining to the equilibrium water sorption properties in both polyesters, and subsequently provides a detailed investigation of the water diffusion process in these materials. [ABSTRACT FROM AUTHOR]

Equilibrium water sorption properties of amorphous poly(ethylene furanoate) (PEF) and amorphous poly(ethylene terephthalate) (PET) were studied at 35 °C over the entire water activity range. PEF exhibits a largely increased equilibrium water sorption capacity of ∼1.8× averaged over the entire concentration range compared to PET, resulting from substitution of the non-polar phenyl ring in PET with the polar furan ring in PEF. Both polyesters exhibit dual-mode sorption up to ∼0.6 activity, after which the onset of swelling produces a noticeable upturn in concentration vs. activity for both polyesters. Excellent agreement was observed between three independent sorption measurement techniques, thereby providing a consistency check for the reported data. Sorption measurements performed at 15, 25, 35, and 45 °C allowed estimation of the effective enthalpy of water sorption for both polyesters, which were similar to the enthalpy of condensation for pure water. The current work demonstrates the importance of structure on sorption and transport properties in these two important polyesters. [ABSTRACT FROM AUTHOR]

Objective: To compare performance of single-injection blood pool agent (gadofosveset trisodium, BPA) against dual-injection extracellular contrast (gadopentetate dimeglumine, ECA) for MRA/MRV in assessment of suspected vascular TOS. Materials and methods: Thirty-one patients referred for vascular TOS evaluation were assessed with BPA (n =18) or ECA (n =13) MRA/MRV in arm abduction and adduction. Images were retrospectively assessed for: image quality (1=non-diagnostic, 5=excellent), vessel contrast (1=same signal as muscle, 4=much brighter than muscle) and vascular pathology by two independent readers, with a separate experienced reader providing reference assessment of vascular pathology. Results: Median image quality was diagnostic or better (score ≥3) for ECA and BPA at all time points, with BPA image quality superior at abduction late (BPA 4.5, ECA 4, p =0.042) and ECA image quality superior at adduction-early (BPA 4.5; ECA 4.0, p =0.018). High qualitative vessel contrast (mean score ≥3) was observed at all time points with both BPA and ECA, with superior BPA vessel contrast at abduction-late (BPA 3.97±0.12; ECA 3.73±0.26, p =0.007) and ECA at adduction-early (BPA 3.42±0.52; ECA 3.96±0.14, p <0.001). Readers readily identified arterial and venous pathology with BPA, similar to ECA examinations. Conclusion: Single-injection BPA MRA/MRV for TOS evaluation demonstrated diagnostic image quality and high vessel contrast, similar to dual-injection ECA imaging, enabling identification of fixed and functional arterial and venous pathology. [ABSTRACT FROM AUTHOR]