Into the Wild: A novel wild-derived inbred strain resource expands the genomic and phenotypic diversity of laboratory mouse models.

The laboratory mouse has served as the premier animal model system for both basic and preclinical investigations for over a century. However, laboratory mice capture only a subset of the genetic variation found in wild mouse populations, ultimately limiting the potential of classical inbred strains to uncover phenotype-associated variants and pathways. Wild mouse populations are reservoirs of genetic diversity that could facilitate the discovery of new functional and disease-associated alleles, but the scarcity of commercially available, well-characterized wild mouse strains limits their broader adoption in biomedical research. To overcome this barrier, we have recently developed, sequenced, and phenotyped a set of 11 inbred strains derived from wild-caught Mus musculus domesticus. Each of these "Nachman strains" immortalizes a unique wild haplotype sampled from one of five environmentally distinct locations across North and South America. Whole genome sequence analysis reveals that each strain carries between 4.73-6.54 million single nucleotide differences relative to the GRCm39 mouse reference, with 42.5% of variants in the Nachman strain genomes absent from current classical inbred mouse strain panels. We phenotyped the Nachman strains on a customized pipeline to assess the scope of disease-relevant neurobehavioral, biochemical, physiological, metabolic, and morphological trait variation. The Nachman strains exhibit significant inter-strain variation in >90% of 1119 surveyed traits and expand the range of phenotypic diversity captured in classical inbred strain panels. These novel wild-derived inbred mouse strain resources are set to empower new discoveries in both basic and preclinical research.

DNA methylation signatures of early-life adversity are exposure-dependent in wild baboons.

The early-life environment can profoundly shape the trajectory of an animal's life, even years or decades later. One mechanism proposed to contribute to these early-life effects is DNA methylation. However, the frequency and functional importance of DNA methylation in shaping early-life effects on adult outcomes is poorly understood, especially in natural populations. Here, we integrate prospectively collected data on fitness-associated variation in the early environment with DNA methylation estimates at 477,270 CpG sites in 256 wild baboons. We find highly heterogeneous relationships between the early-life environment and DNA methylation in adulthood: aspects of the environment linked to resource limitation (e.g., low-quality habitat, early-life drought) are associated with many more CpG sites than other types of environmental stressors (e.g., low maternal social status). Sites associated with early resource limitation are enriched in gene bodies and putative enhancers, suggesting they are functionally relevant. Indeed, by deploying a baboon-specific, massively parallel reporter assay, we show that a subset of windows containing these sites are capable of regulatory activity, and that, for 88% of early drought-associated sites in these regulatory windows, enhancer activity is DNA methylation-dependent. Together, our results support the idea that DNA methylation patterns contain a persistent signature of the early-life environment. However, they also indicate that not all environmental exposures leave an equivalent mark and suggest that socioenvironmental variation at the time of sampling is more likely to be functionally important. Thus, multiple mechanisms must converge to explain early-life effects on fitness-related traits.

Into the Wild: A novel wild-derived inbred strain resource expands the genomic and phenotypic diversity of laboratory mouse models.

The laboratory mouse has served as the premier animal model system for both basic and preclinical investigations for a century. However, laboratory mice capture a narrow subset of the genetic variation found in wild mouse populations. This consideration inherently restricts the scope of potential discovery in laboratory models and narrows the pool of potentially identified phenotype-associated variants and pathways. Wild mouse populations are reservoirs of predicted functional and disease-associated alleles, but the sparsity of commercially available, well-characterized wild mouse strains limits their broader adoption in biomedical research. To overcome this barrier, we have recently imported, sequenced, and phenotyped a set of 11 wild-derived inbred strains developed from wild-caught Mus musculus domesticus. Each of these "Nachman strains" immortalizes a unique wild haplotype sampled from five environmentally diverse locations across North and South America: Saratoga Springs, New York, USA; Gainesville, Florida, USA; Manaus, Brazil; Tucson, Arizona, USA; and Edmonton, Alberta, Canada. Whole genome sequence analysis reveals that each strain carries between 4.73-6.54 million single nucleotide differences relative to the mouse reference assembly, with 42.5% of variants in the Nachman strain genomes absent from classical inbred mouse strains. We phenotyped the Nachman strains on a customized pipeline to assess the scope of disease-relevant neurobehavioral, biochemical, physiological, metabolic, and morphological trait variation. The Nachman strains exhibit significant inter-strain variation in >90% of 1119 surveyed traits and expand the range of phenotypic diversity captured in classical inbred strain panels alone. Taken together, our work introduces a novel wild-derived inbred mouse strain resource that will enable new discoveries in basic and preclinical research. These strains are currently available through The Jackson Laboratory Repository under laboratory code NachJ.

Designing Clinical MRI for Enhanced Workflow and Value.

MRI is an expensive and traditionally time-intensive modality in imaging. With the paradigm shift toward value-based healthcare, radiology departments must examine the entire MRI process cycle to identify opportunities to optimize efficiency and enhance value for patients. Digital tools such as "frictionless scheduling" prioritize patient preference and convenience, thereby delivering patient-centered care. Recent advances in conventional and deep learning-based accelerated image reconstruction methods have reduced image acquisition time to such a degree that so-called nongradient time now constitutes a major percentage of total room time. For this reason, architectural design strategies that reconfigure patient preparation processes and decrease the turnaround time between scans can substantially impact overall throughput while also improving patient comfort and privacy. Real-time informatics tools that provide an enterprise-wide overview of MRI workflow and Picture Archiving and Communication System (PACS)-integrated instant messaging can complement these efforts by offering transparent, situational data and facilitating communication between radiology team members. Finally, long-term investment in training, recruiting, and retaining a highly skilled technologist workforce is essential for building a pipeline and team of technologists committed to excellence. Here, we highlight various opportunities for optimizing MRI workflow and enhancing value by offering many of our own on-the-ground experiences and conclude by anticipating some of the future directions for process improvement and innovation in clinical MR imaging. EVIDENCE LEVEL: N/A TECHNICAL EFFICACY: Stage 1.

Usability of ENTRUST as an Assessment Tool for Entrustable Professional Activities (EPAs): A Mixed Methods Analysis.

OBJECTIVE: As the American Board of Surgery transitions to a competency-based model of surgical education centered upon entrustable professional activities (EPAs), there is a growing need for objective tools to determine readiness for entrustment. This study evaluates the usability of ENTRUST, an innovative virtual patient simulation platform to assess surgical trainees' decision-making skills in preoperative, intra-operative, and post-operative settings. DESIGN: This is a mixed-methods analysis of the usability of the ENTRUST platform. Quantitative data was collected using the system usability scale (SUS) and Likert responses. Analysis was performed with descriptive statistics, bivariate analysis, and multivariable linear regression. Qualitative analysis of open-ended responses was performed using the Nielsen-Shneiderman Heuristics framework. SETTING: This study was conducted at an academic institution in a proctored exam setting. PARTICIPANTS: The analysis includes n = 47 (PGY 1-5) surgical residents who completed an online usability survey following the ENTRUST Inguinal Hernia EPA Assessment. RESULTS: The ENTRUST platform had a median SUS score of 82.5. On bivariate and multivariate analyses, there were no significant differences between usability based on demographic characteristics (all p > 0.05), and SUS score was independent of ENTRUST performance (r = 0.198, p = 0.18). Most participants agreed that the clinical workup of the patient was engaging (91.5%) and felt realistic (85.1%). The most frequent heuristics represented in the qualitative analysis included feedback, visibility, match, and control. Additional themes of educational value, enjoyment, and ease-of-use highlighted participants' perspectives on the usability of ENTRUST. CONCLUSIONS: ENTRUST demonstrates high usability in this population. Usability was independent of ENTRUST score performance and there were no differences in usability identified in this analysis based on demographic subgroups. Qualitative analysis highlighted the acceptability of ENTRUST and will inform ongoing development of the platform. The ENTRUST platform holds potential as a tool for the assessment of EPAs in surgical residency programs.

DNA methylation signatures of early life adversity are exposure-dependent in wild baboons.

The early life environment can profoundly shape the trajectory of an animal's life, even years or decades later. One mechanism proposed to contribute to these early life effects is DNA methylation. However, the frequency and functional importance of DNA methylation in shaping early life effects on adult outcomes is poorly understood, especially in natural populations. Here, we integrate prospectively collected data on fitness-associated variation in the early environment with DNA methylation estimates at 477,270 CpG sites in 256 wild baboons. We find highly heterogeneous relationships between the early life environment and DNA methylation in adulthood: aspects of the environment linked to resource limitation (e.g., low-quality habitat, early life drought) are associated with many more CpG sites than other types of environmental stressors (e.g., low maternal social status). Sites associated with early resource limitation are enriched in gene bodies and putative enhancers, suggesting they are functionally relevant. Indeed, by deploying a baboon-specific, massively parallel reporter assay, we show that a subset of windows containing these sites are capable of regulatory activity, and that, for 88% of early drought-associated sites in these regulatory windows, enhancer activity is DNA methylation-dependent. Together, our results support the idea that DNA methylation patterns contain a persistent signature of the early life environment. However, they also indicate that not all environmental exposures leave an equivalent mark and suggest that socioenvironmental variation at the time of sampling is more likely to be functionally important. Thus, multiple mechanisms must converge to explain early life effects on fitness-related traits.

ENTRUST: A Serious Game-Based Virtual Patient Platform to Assess Entrustable Professional Activities in Graduate Medical Education.

Background: As entrustable professional activities (EPAs) are implemented in graduate medical education, there is a great need for tools to efficiently and objectively evaluate clinical competence. Readiness for entrustment in surgery requires not only assessment of technical ability, but also the critical skill of clinical decision-making. Objective: We report the development of ENTRUST, a serious game-based, virtual patient case creation and simulation platform to assess trainees' decision-making competence. A case scenario and corresponding scoring algorithm for the Inguinal Hernia EPA was iteratively developed and aligned with the description and essential functions outlined by the American Board of Surgery. In this study we report preliminary feasibility data and validity evidence. Methods: In January 2021, the case scenario was deployed and piloted on ENTRUST with 19 participants of varying surgical expertise levels to demonstrate proof of concept and initial validity evidence. Total score, preoperative sub-score, and intraoperative sub-score were analyzed by training level and years of medical experience using Spearman rank correlations. Participants completed a Likert scale user acceptance survey (1=strongly agree to 7=strongly disagree). Results: Median total score and intraoperative mode sub-score were higher with each progressive level of training (rho=0.79, P<.001 and rho=0.69, P=.001, respectively). There were significant correlations between performance and years of medical experience for total score (rho=0.82, P<.001) and intraoperative sub-scores (rho=0.70, P<.001). Participants reported high levels of platform engagement (mean 2.06) and ease of use (mean 1.88). Conclusions: Our study demonstrates feasibility and early validity evidence for ENTRUST as an assessment platform for clinical decision-making.

Correlation of Performance on ENTRUST and Traditional Oral Objective Structured Clinical Examination for High-Stakes Assessment in the College of Surgeons of East, Central, and Southern Africa.

BACKGROUND: To address the global need for accessible evidence-based tools for competency-based education, we developed ENTRUST, an innovative online virtual patient simulation platform to author and securely deploy case scenarios to assess surgical decision-making competence. STUDY DESIGN: In partnership with the College of Surgeons of East, Central, and Southern Africa, ENTRUST was piloted during the Membership of the College of Surgeons (MCS) 2021 examination. Examinees (n = 110) completed the traditional 11-station oral objective structured clinical examinations (OSCEs), followed by 3 ENTRUST cases, authored to query similar clinical content of 3 corresponding OSCE cases. ENTRUST scores were analyzed for associations with MCS Examination outcome using independent sample t tests. Correlation of ENTRUST scores to MCS Examination Percentage and OSCE station scores was calculated with Pearson correlations. Bivariate and multivariate analyses were performed to evaluate predictors of performance. RESULTS: ENTRUST performance was significantly higher in examinees who passed the MCS examination compared with those who failed (p < 0.001). The ENTRUST score was positively correlated with MCS Examination Percentage (p < 0.001) and combined OSCE station scores (p < 0.001). On multivariate analysis, there was a strong association between MCS Examination Percentage and ENTRUST Grand Total Score (p < 0.001), Simulation Total Score (p = 0.018), and Question Total Score (p < 0.001). Age was a negative predictor for ENTRUST Grand Total and Simulation Total Score, but not for Question Total Score. Sex, native language status, and intended specialty were not associated with performance on ENTRUST. CONCLUSIONS: This study demonstrates feasibility and initial validity evidence for the use of ENTRUST in a high-stakes examination context for assessment of surgical decision-making. ENTRUST holds potential as an accessible learning and assessment platform for surgical trainees worldwide.

Increased Risk of Complications Associated With Concurrent Parathyroidectomy in Patients Undergoing Total Thyroidectomy.

INTRODUCTION: We sought to investigate the association of concurrent parathyroidectomy (PTX) with risks of total thyroidectomy (TTX) through analysis of Collaborative Endocrine Surgery Quality Improvement Program data. TTXis a common operation with complications including recurrent laryngeal nerve injury, neck hematoma, and hypoparathyroidism. A subset of patients undergoing thyroidectomy undergoes planned concurrent PTX for treatment of primary hyperparathyroidism. There are limited data on the risk profile of TTX with concurrent PTX (TTX + PTX). METHODS: We queried the Collaborative Endocrine Surgery Quality Improvement Program database for patients who underwent TTX or TTX + PTX from January 2014 through April 2020. Multivariable logistic regression was performed to predict hypoparathyroidism, vocal cord dysfunction, neck hematoma, and postoperative emergency department visit. Covariates included patient demographics, patient body mass index, indication for surgery, central neck dissection, anticoagulation use, and surgeon volume. RESULTS: Thirteen thousand six hundred forty seven patients underwent TTX and 654 patients underwent TTX + PTX. Unadjusted rates of hypoparathyroidism were higher in TTX + PTX patients at 30 d (9.6% versus 7.4%, P = 0.04) and 6 mo (7.9% versus 3.1%, P < 0.001). On multivariable regression, TTX + PTX was associated with an increased risk of hypoparathyroidism at 30 d (odds ratio [OR] 2.09, 95% confidence interval [CI] 1.57-2.79) and 6 mo (OR 4.63, 95% CI 3.06-7.00) and an increased risk of postoperative emergency department visit (OR 1.66, 95% CI 1.20-2.31). TTX + PTX was not associated with recurrent laryngeal nerve injury or neck hematoma. CONCLUSIONS: Concurrent PTX in patients undergoing TTX is associated with increased risk of immediate and long-term hypoparathyroidism, which should be considered in informed consent discussions and operative decision-making.

Deep Learning Diagnosis and Classification of Rotator Cuff Tears on Shoulder MRI.

BACKGROUND: Detection of rotator cuff tears, a common cause of shoulder disability, can be time-consuming and subject to reader variability. Deep learning (DL) has the potential to increase radiologist accuracy and consistency. PURPOSE: The aim of this study was to develop a prototype DL model for detection and classification of rotator cuff tears on shoulder magnetic resonance imaging into no tear, partial-thickness tear, or full-thickness tear. MATERIALS AND METHODS: This Health Insurance Portability and Accountability Act-compliant, institutional review board-approved study included a total of 11,925 noncontrast shoulder magnetic resonance imaging scans from 2 institutions, with 11,405 for development and 520 dedicated for final testing. A DL ensemble algorithm was developed that used 4 series as input from each examination: fluid-sensitive sequences in 3 planes and a sagittal oblique T1-weighted sequence. Radiology reports served as ground truth for training with categories of no tear, partial tear, or full-thickness tear. A multireader study was conducted for the test set ground truth, which was determined by the majority vote of 3 readers per case. The ensemble comprised 4 parallel 3D ResNet50 convolutional neural network architectures trained via transfer learning and then adapted to the targeted domain. The final tear-type prediction was determined as the class with the highest probability, after averaging the class probabilities of the 4 individual models. RESULTS: The AUC overall for supraspinatus, infraspinatus, and subscapularis tendon tears was 0.93, 0.89, and 0.90, respectively. The model performed best for full-thickness supraspinatus, infraspinatus, and subscapularis tears with AUCs of 0.98, 0.99, and 0.95, respectively. Multisequence input demonstrated higher AUCs than single-sequence input for infraspinatus and subscapularis tendon tears, whereas coronal oblique fluid-sensitive and multisequence input showed similar AUCs for supraspinatus tendon tears. Model accuracy for tear types and overall accuracy were similar to that of the clinical readers. CONCLUSIONS: Deep learning diagnosis of rotator cuff tears is feasible with excellent diagnostic performance, particularly for full-thickness tears, with model accuracy similar to subspecialty-trained musculoskeletal radiologists.

Deep Learning Reconstruction Enables Prospectively Accelerated Clinical Knee MRI.

Background MRI is a powerful diagnostic tool with a long acquisition time. Recently, deep learning (DL) methods have provided accelerated high-quality image reconstructions from undersampled data, but it is unclear if DL image reconstruction can be reliably translated to everyday clinical practice. Purpose To determine the diagnostic equivalence of prospectively accelerated DL-reconstructed knee MRI compared with conventional accelerated MRI for evaluating internal derangement of the knee in a clinical setting. Materials and Methods A DL reconstruction model was trained with images from 298 clinical 3-T knee examinations. In a prospective analysis, patients clinically referred for knee MRI underwent a conventional accelerated knee MRI protocol at 3 T followed by an accelerated DL protocol between January 2020 and February 2021. The equivalence of the DL reconstruction of the images relative to the conventional images for the detection of an abnormality was assessed in terms of interchangeability. Each examination was reviewed by six musculoskeletal radiologists. Analyses pertaining to the detection of meniscal or ligament tears and bone marrow or cartilage abnormalities were based on four-point ordinal scores for the likelihood of an abnormality. Additionally, the protocols were compared with use of four-point ordinal scores for each aspect of image quality: overall image quality, presence of artifacts, sharpness, and signal-to-noise ratio. Results A total of 170 participants (mean age ± SD, 45 years ± 16; 76 men) were evaluated. The DL-reconstructed images were determined to be of diagnostic equivalence with the conventional images for detection of abnormalities. The overall image quality score, averaged over six readers, was significantly better (P < .001) for the DL than for the conventional images. Conclusion In a clinical setting, deep learning reconstruction enabled a nearly twofold reduction in scan time for a knee MRI and was diagnostically equivalent with the conventional protocol. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Roemer in this issue.

Risk of Permanent Hypoparathyroidism Requiring Calcitriol Therapy in a Population-Based Cohort of Adults Older Than 65 Undergoing Total Thyroidectomy for Graves' Disease.

Objective: Total thyroidectomy for Graves' disease (GD) is associated with rapid treatment of hyperthyroidism and low recurrence rates. However, it carries the risk of surgical complications including permanent hypoparathyroidism, which contributes to long-term impaired quality of life. The objective of this study was to determine the incidence of permanent hypoparathyroidism requiring calcitriol therapy among a population-based cohort of older adults undergoing total thyroidectomy for GD in the United States. Methods: We performed a population-based cohort study using 100% Medicare claims from beneficiaries older than 65 years with GD who underwent total thyroidectomy from 2007 to 2017. We required continuous enrollment in Medicare Parts A, B, and D for 12 months before and after surgery to ensure access to comprehensive claims data. Patients were excluded if they had a preoperative diagnosis of thyroid cancer or were on long-term preoperative calcitriol. Our primary outcome was permanent hypoparathyroidism, which was identified based on persistent use of calcitriol between 6 and 12 months following thyroidectomy. We used multivariable logistic regression to identify characteristics associated with permanent hypoparathyroidism, including patient age, sex, race/ethnicity, neighborhood disadvantage, Charlson-Deyo Comorbidity Index, urban or rural residence, and frailty. Results: We identified 4650 patients who underwent total thyroidectomy for GD during the study period and met the inclusion criteria (mean age = 72.8 years [standard deviation = 5.5], 86% female, and 79% white). Among this surgical cohort, 104 (2.2% [95% confidence interval, CI = 1.8-2.7%]) patients developed permanent hypoparathyroidism requiring calcitriol therapy. Patients who developed permanent hypoparathyroidism were on average older (mean age 74.1 vs. 72.8 years) than those who did not develop permanent hypoparathyroidism (p = 0.04). On multivariable regression, older age was the only patient characteristic associated with permanent hypoparathyroidism (odds ratio age ≥76 years = 1.68 [CI = 1.13-2.51] compared with age 66-75 years). Conclusions: The risk of permanent hypoparathyroidism requiring calcitriol therapy among this national, U.S. population-based cohort of older adults with GD treated with total thyroidectomy was low, even when considering operations performed by a heterogeneous group of surgeons. These findings suggest that the risk of hypoparathyroidism should not be a deterrent to operative management for GD in older adults who are appropriate surgical candidates.

Adverse Cardiovascular Outcomes Among Older Adults With Primary Hyperparathyroidism Treated With Parathyroidectomy Versus Nonoperative Management.

OBJECTIVE: The authors sought to compare the incidence of adverse cardiovascular (CV) events in older adults with primary hyperparathyroidism (PHPT) treated with parathyroidectomy versus nonoperative management. BACKGROUND: PHPT is a common endocrine disorder that is associated with increased CV mortality, but it is not known whether parathyroidectomy reduces the incidence of adverse CV events. METHODS: The authors conducted a population-based, longitudinal cohort study of Medicare beneficiaries diagnosed with PHPT (2006-2017). Multivariable, inverse probability weighted Cox proportional hazards regression was used to determine the associations of parathyroidectomy with major adverse cardiovascular events (MACEs), CV disease-related hospitalization, and CV hospitalization-associated mortality. RESULTS: The authors identified 210,206 beneficiaries diagnosed with PHPT from 2006 to 2017. Among 63,136 (30.0%) treated with parathyroidectomy and 147,070 (70.0%) managed nonoperatively within 1 year of diagnosis, the unadjusted incidence of MACE was 10.0% [mean follow-up 59.1 (SD 35.6) months] and 11.5% [mean follow-up 54.1 (SD 34.0) months], respectively. In multivariable analysis, parathyroidectomy was associated with a lower incidence of MACE [hazard ratio (HR): 0.92; 95% confidence interval (95% CI): 0.90-0.94], CV disease-related hospitalization (HR: 0.89; 95% CI: 0.87-0.91), and CV hospitalization-associated mortality (HR: 0.76; 95% CI: 0.71-0.81) compared to nonoperative management. At 10 years, parathyroidectomy was associated with adjusted absolute risk reduction for MACE of 1.7% (95% CI: 1.3%-2.1%), for CV disease-related hospitalization of 2.5% (95% CI: 2.1%-2.9%), and for CV hospitalization-associated mortality of 1.4% (95% CI: 1.2%-1.6%). CONCLUSIONS: In this large, population-based cohort study, parathyroidectomy was associated with a lower long-term incidence of adverse CV outcomes when compared with nonoperative management for older adults with PHPT, which is relevant to surgical decision making for patients with a long life expectancy.

Artificial Intelligence-Driven Ultra-Fast Superresolution MRI: 10-Fold Accelerated Musculoskeletal Turbo Spin Echo MRI Within Reach.

ABSTRACT: Magnetic resonance imaging (MRI) is the keystone of modern musculoskeletal imaging; however, long pulse sequence acquisition times may restrict patient tolerability and access. Advances in MRI scanners, coil technology, and innovative pulse sequence acceleration methods enable 4-fold turbo spin echo pulse sequence acceleration in clinical practice; however, at this speed, conventional image reconstruction approaches the signal-to-noise limits of temporal, spatial, and contrast resolution. Novel deep learning image reconstruction methods can minimize signal-to-noise interdependencies to better advantage than conventional image reconstruction, leading to unparalleled gains in image speed and quality when combined with parallel imaging and simultaneous multislice acquisition. The enormous potential of deep learning-based image reconstruction promises to facilitate the 10-fold acceleration of the turbo spin echo pulse sequence, equating to a total acquisition time of 2-3 minutes for entire MRI examinations of joints without sacrificing spatial resolution or image quality. Current investigations aim for a better understanding of stability and failure modes of image reconstruction networks, validation of network reconstruction performance with external data sets, determination of diagnostic performances with independent reference standards, establishing generalizability to other centers, scanners, field strengths, coils, and anatomy, and building publicly available benchmark data sets to compare methods and foster innovation and collaboration between the clinical and image processing community. In this article, we review basic concepts of deep learning-based acquisition and image reconstruction techniques for accelerating and improving the quality of musculoskeletal MRI, commercially available and developing deep learning-based MRI solutions, superresolution, denoising, generative adversarial networks, and combined strategies for deep learning-driven ultra-fast superresolution musculoskeletal MRI. This article aims to equip radiologists and imaging scientists with the necessary practical knowledge and enthusiasm to meet this exciting new era of musculoskeletal MRI.

Group A Beta-Hemolytic Streptococcus-Induced Tic-Like Movement Disorder in an Adult: A Case Report.

A tic is a sudden, repeated, quick, and uncontrollable movement of a part of the body. Tic disorders have a multifactorial etiology, including genetic predisposition, autoimmunity, and environmental factors. Movement disorders following streptococcal infection are rare and typically present in the pediatric population. We present a unique case of a 31-year-old female admitted with involuntary movements of the upper extremities of three weeks duration. Her movements start as twitching before progressing to one hand hitting the other or hitting her face. She had a strong urge before giving in to complete the action. However, the movements were partially distractable, with considerable overlap between clinical features of organic and functional tics. After a detailed workup, including a negative magnetic resonance imaging (MRI) of the brain with and without contrast, MRI of the spine, computed tomography of the chest, abdomen, and pelvis for neoplasia, as well as blood work for autoimmunity, infections, and paraneoplastic syndrome, the serology came back strongly positive for antistreptolysin O and antideoxyribonuclease B titers. Additionally, a detailed psychiatric assessment ruled out conversion disorder leading to a diagnosis of streptococcus-induced movement disorder. After a failed inpatient trial of aripiprazole, the plan included initiating deutetrabenazine with close outpatient neurology follow-up after discharge.

Validity Evidence for ENTRUST as an Assessment of Surgical Decision-Making for the Inguinal Hernia Entrustable Professional Activity (EPA).

OBJECTIVE: As the American Board of Surgery (ABS) moves toward implementation of Entrustable Professional Activities (EPAs), there is a growing need for objective evaluation of readiness for entrustment of residents. This requires not only assessment of technical skills and knowledge, but also surgical decision-making in preoperative, intraoperative, and postoperative settings. We developed and piloted an Inguinal Hernia EPA Assessment on ENTRUST, a serious game-based online virtual patient simulation platform to assess trainees' decision-making competence. DESIGN: This is a prospective analysis of resident performance on the ENTRUST Inguinal Hernia EPA Assessment using bivariate analyses. SETTING: This study was conducted at an academic institution in a proctored exam setting. PARTICIPANTS: Forty-three surgical residents completed the ENTRUST Inguinal Hernia EPA Assessment. RESULTS: Four case scenarios for the Inguinal Hernia EPA and corresponding scoring algorithms were iteratively developed by expert consensus aligned with ABS EPA descriptions and functions. ENTRUST Inguinal Hernia Grand Total Score was positively correlated with PGY-level (p < 0.0001). Preoperative, Intraoperative, and Postoperative Total Scores were also positively correlated with PGY-level (p = 0.001, p = 0.006, and p = 0.038, respectively). Total Case Scores were positively correlated with PGY-level for cases representing elective unilateral inguinal hernia (p = 0.0004), strangulated inguinal hernia (p < 0.0001), and elective bilateral inguinal hernia (p = 0.0003). Preoperative Sub-Scores were positively correlated with PGY-level for all cases (p < 0.01). Intraoperative Sub-Scores were positively correlated with PGY-level for strangulated inguinal hernia and bilateral inguinal hernia (p = 0.0007 and p = 0.0002, respectively). Grand Total Score and Intraoperative Sub-Score were correlated with prior operative experience (p < 0.0001). Prior video game experience did not correlate with performance on ENTRUST (p = 0.56). CONCLUSIONS: Performance on the ENTRUST Inguinal Hernia EPA Assessment was positively correlated to PGY-level and prior inguinal hernia operative performance, providing initial validity evidence for its use as an objective assessment for surgical decision-making. The ENTRUST platform holds potential as tool for assessment of ABS EPAs in surgical residency programs.

New-Generation Low-Field Magnetic Resonance Imaging of Hip Arthroplasty Implants Using Slice Encoding for Metal Artifact Correction: First In Vitro Experience at 0.55 T and Comparison With 1.5 T.

OBJECTIVES: Despite significant progress, artifact-free visualization of the bone and soft tissues around hip arthroplasty implants remains an unmet clinical need. New-generation low-field magnetic resonance imaging (MRI) systems now include slice encoding for metal artifact correction (SEMAC), which may result in smaller metallic artifacts and better image quality than standard-of-care 1.5 T MRI. This study aims to assess the feasibility of SEMAC on a new-generation 0.55 T system, optimize the pulse protocol parameters, and compare the results with those of a standard-of-care 1.5 T MRI. MATERIALS AND METHODS: Titanium (Ti) and cobalt-chromium total hip arthroplasty implants embedded in a tissue-mimicking American Society for Testing and Materials gel phantom were evaluated using turbo spin echo, view angle tilting (VAT), and combined VAT and SEMAC (VAT + SEMAC) pulse sequences. To refine an MRI protocol at 0.55 T, the type of metal artifact reduction techniques and the effect of various pulse sequence parameters on metal artifacts were assessed through qualitative ranking of the images by 3 expert readers while taking measured spatial resolution, signal-to-noise ratios, and acquisition times into consideration. Signal-to-noise ratio efficiency and artifact size of the optimized 0.55 T protocols were compared with the 1.5 T standard and compressed-sensing SEMAC sequences. RESULTS: Overall, the VAT + SEMAC sequence with at least 6 SEMAC encoding steps for Ti and 9 for cobalt-chromium implants was ranked higher than other sequences for metal reduction ( P < 0.05). Additional SEMAC encoding partitions did not result in further metal artifact reductions. Permitting minimal residual artifacts, low magnetic susceptibility Ti constructs may be sufficiently imaged with optimized turbo spin echo sequences obviating the need for SEMAC. In cross-platform comparison, 0.55 T acquisitions using the optimized protocols are associated with 45% to 64% smaller artifacts than 1.5 T VAT + SEMAC and VAT + compressed-sensing/SEMAC protocols at the expense of a 17% to 28% reduction in signal-to-noise ratio efficiency. B 1 -related artifacts are invariably smaller at 0.55 T than 1.5 T; however, artifacts related to B 0 distortion, although frequently smaller, may appear as signal pileups at 0.55 T. CONCLUSIONS: Our results suggest that new-generation low-field SEMAC MRI reduces metal artifacts around hip arthroplasty implants to better advantage than current 1.5 T MRI standard of care. While the appearance of B 0 -related artifacts changes, reduction in B 1 -related artifacts plays a major role in the overall benefit of 0.55 T.

How Does a "Dry Tap" Impact the Accuracy of Preoperative Aspiration Results in Predicting Chronic Periprosthetic Joint Infection?

BACKGROUND: Periprosthetic joint infection (PJI) after total hip arthroplasty (THA) is challenging to diagnose. We aimed to evaluate the impact of dry taps requiring saline lavage during preoperative intra-articular hip aspiration on the accuracy of diagnosing PJI before revision surgery. METHODS: A retrospective review was conducted for THA patients with suspected PJI who received an image-guided hip aspiration from May 2016 to February 2020. Musculoskeletal Infection Society (MSIS) diagnostic criteria for PJI were compared between patients who had dry tap (DT) vs successful tap (ST). Sensitivity and specificity of synovial markers were compared between the DT and ST groups. Concordance between preoperative and intraoperative cultures was determined for the 2 groups. RESULTS: In total, 335 THA patients met inclusion criteria. A greater proportion of patients in the ST group met MSIS criteria preoperatively (30.2% vs 8.3%, P < .001). Patients in the ST group had higher rates of revision for PJI (28.4% vs 17.5%, P = .026) and for any indication (48.4% vs 36.7%, P = .039). MSIS synovial white blood cell count thresholds were more sensitive in the ST group (90.0% vs 66.7%). There was no difference in culture concordance (67.9% vs 65.9%, P = .709), though the DT group had a higher rate of negative preoperative cultures followed by positive intraoperative cultures (85.7% vs 41.1%, P = .047). CONCLUSION: Our results indicate that approximately one third of patients have dry hip aspiration, and in these patients cultures are less predictive of intraoperative findings. This suggests that surgeons considering potential PJI after THA should apply extra scrutiny when interpreting negative results in patients who require saline lavage for hip joint aspiration.

Factors predicting hip joint aspiration yield or "dry taps" in patients with total hip arthroplasty.

BACKGROUND: Image-guided joint aspirations used to assist the diagnosis of periprosthetic joint infection (PJI) may commonly result in a dry tap-or insufficient fluid for culture and cell count analysis. Dry tap aspirations are painful and invasive for patients and often utilize a subsequent saline lavage to obtain a microbiology sample. Currently, there is a paucity of the literature addressing predictors that could suggest whether a dry tap will occur. The purpose of this study was to examine the effects of various factors on "dry tap" occurrence in patients with suspected PJI following total hip arthroplasty (THA). METHODS: A retrospective review was performed among THA patients suspected for PJI who received image-guided joint aspiration procedures at our institution from May 2016 to February 2020. The procedural factors included the imaging modality used for aspiration, anatomic approach, needle gauge size used, and the presence of a trainee. The patient-specific factors included number of prior ipsilateral hip surgeries, femoral head size, ESR/CRP values, and BMI. RESULTS: In total, 336 patients met our inclusion criteria. One hundred and twenty hip aspirations resulted in a dry tap (35.7%) where the patients underwent a saline lavage. Among the procedural and patient-specific factors, none of the factors were found to be statistically different between the two cohorts nor conferred any greater odds of a dry tap occurring. CONCLUSION: No associations with dry tap occurrence were found among the procedural and patient-specific factors studied. Further research is needed to identify additional factors that may be more predictive of dry taps.

Racial disparities in the utilization of parathyroidectomy among patients with primary hyperparathyroidism: Evidence from a nationwide analysis of Medicare claims.

BACKGROUND: Among patients with primary hyperparathyroidism, parathyroidectomy offers a chance of cure and mitigation of disease-related complications. The impact of race/ethnicity on referral and utilization of parathyroidectomy has not been fully explored. METHODS: Population-based, retrospective cohort study using 100% Medicare claims from beneficiaries with primary hyperparathyroidism from 2006 to 2016. Associations of race/ethnicity with disease severity, surgeon evaluation, and subsequent parathyroidectomy were analyzed using adjusted multivariable logistic regression models. RESULTS: Among 210,206 beneficiaries with primary hyperparathyroidism, 63,136 (30.0%) underwent parathyroidectomy within 1 year of diagnosis. Black patients were more likely than other races/ethnicities to have stage 3 chronic kidney disease (10.8%) but had lower prevalence of osteoporosis and nephrolithiasis compared to White patients, Black and Hispanic patients were more likely to have been hospitalized for primary hyperparathyroidism-associated conditions (White 4.8%, Black 8.1%, Hispanic 5.8%; P < .001). Patients who were White and met operative criteria were more likely to undergo parathyroidectomy than Black, Hispanic, or Asian patients (White 30.5%, Black 23.0%, Hispanic 21.4%, Asian 18.7%; P < .001). Black and Hispanic patients had lower adjusted odds of being evaluated by a surgeon (odds ratios 0.71 [95% confidence interval 0.69-0.74], 0.68 [95% confidence interval 0.61-0.74], respectively) and undergoing parathyroidectomy if evaluated by a surgeon (odds ratios 0.72 [95% confidence interval 0.68-0.77], 0.82 [95% confidence interval 0.67-0.99]). Asian race was associated with lower adjusted odds of being evaluated by a surgeon (odds ratio 0.64 [95% confidence interval 0.57-0.71]), but no difference in odds of parathyroidectomy. CONCLUSION: Racial/ethnic disparities exist in the management of primary hyperparathyroidism among older adults. Determining the factors that account for this disparity require urgent attention to achieve parity in the management of primary hyperparathyroidism.