Boosting the Sensitivity of Quantitative Single-Cell Proteomics with Infrared-Tandem Mass Tags.

Single-cell proteomics is a powerful approach to precisely profile protein landscapes within individual cells toward a comprehensive understanding of proteomic functions and tissue and cellular states. The inherent challenges associated with limited starting material demand heightened analytical sensitivity. Just as advances in sample preparation maximize the amount of material that makes it from the cell to the mass spectrometer, we strive to maximize the number of ions that make it from ion source to the detector. In isobaric tagging experiments, limited reporter ion generation limits quantitative accuracy and precision. The combination of infrared photoactivation and ion parking circumvents the m/z dependence inherent in HCD, maximizing reporter generation and avoiding unintended degradation of TMT reporter molecules in infrared-tandem mass tags (IR-TMT). The method was applied to single-cell human proteomes using 18-plex TMTpro, resulting in 4-5-fold increases in reporter signal compared to conventional SPS-MS3 approaches. IR-TMT enables faster duty cycles, higher throughput, and increased peptide identification and quantification. Comparative experiments showcase 4-5-fold lower injection times for IR-TMT, providing superior sensitivity without compromising accuracy. In all, IR-TMT enhances the dynamic range of proteomic experiments and is compatible with gas-phase fractionation and real-time searching, promising increased gains in the study of cellular heterogeneity.

A Case of Unilateral Simultaneous Preauricular Sinus and Postauricular Sinus in an Adult.

Preauricular sinuses are relatively common congenital anomalies of the soft tissues of the ear. By strict definition, when they connect 2 separate spaces, they are referred to as a preauricular fistula. This clinical entity was first described by Heusinger in 1864. Most preauricular sinuses have a small opening located anterior to the root of the helix. In rare cases, they are found posterior to the tragus, near the crus of the helix, and the ear lobule. The latter is the variant type preauricular sinus, also referred to as the "postauricular sinus," as the sinus tract opens posterior to the auricle. Recurrent infections or persistent discharge may require surgical excision which is ideally performed at a time when there is no inflammation. There are a variety of techniques for excision. Regardless of the surgical approach taken, it is of critical importance to remove the subcutaneous sac completely. We present a very rare case involving the co-occurrence of a preauricular sinus and postauricular sinus in a 33-year-old woman. We report this case with a review of the literature.

Utilising a 'Community of Practice' to support pharmacists to work in residential aged care: protocol for a longitudinal evaluation.

INTRODUCTION: A Community of Practice is briefly defined as a group of people with a shared interest in a given area of practice who work collaboratively to grow collective knowledge. Communities of Practice have been used to facilitate knowledge exchange and improve evidence-based practice. Knowledge translation within the residential aged care sector is lacking, with barriers such as inadequate staffing and knowledge gaps commonly cited. In Australia, a Federal inquiry into residential aged care practices led to a recommendation to embed pharmacists within residential aged care facilities. Onsite practice in aged care is a new role for pharmacists in Australia. Thus, support is needed to enable pharmacists to practice in this role.The primary aim is to evaluate the processes and outcomes of a Community of Practice designed to support pharmacists to work in aged care. METHODS AND ANALYSIS: A longitudinal, single-group, pretest-post-test design in which the intervention is a Community of Practice. The Community of Practice will be established and made available for 3 years to all Australian pharmacists interested in, new to or established in aged care roles. The Community of Practice will be hosted on online discussion platforms, with additional virtual meetings and annual symposia. The following data will be collected from all members of the Community of Practice: self-evaluation of the processes and outcomes of the Community of Practice (via the CoPeval scale) and confidence in evidence-based practice (EPIC scale), collected via online questionnaires annually; and discussion platform usage statistics and discussion transcripts. A subset of members will be invited to participate in annual semi-structured individual interviews.Data from the online questionnaire will be analysed descriptively. Discussion transcripts will be analysed using topic modelling and content analysis to identify the common topics discussed and their frequencies. Qualitative data from individual interviews will be thematically analysed to explore perceptions and experiences with the intervention for information/knowledge exchange, impact on practice, and sharing/promoting/implementing evidence-based practice. ETHICS AND DISSEMINATION: Human ethics approval has been granted by the University of Western Australia's Human Ethics Committee (2023/ET000000). No personal information will be included in any publications and reports to funding bodies.Findings will be disseminated to all members of the Community of Practice, professional organisations, social and mass media, peer-review journals, research and professional conferences and annual reports to the funding body.

Imaging of Peripheral Nerves: AJR Expert Panel Narrative Review.

Peripheral nerve imaging provides information that can be critical to the diagnosis, staging, and management of peripheral neuropathies. MRI and ultrasound are the imaging modalities of choice for clinical evaluation of the peripheral nerves given their high soft tissue contrast and high resolution, respectively. This AJR Expert Panel Narrative Review describes MRI- and ultrasound-based techniques for peripheral nerve imaging; highlights considerations for imaging in the settings of trauma, entrapment syndromes, diffuse inflammatory neuropathies, and tumor; and discusses image-guided nerve interventions, focusing on nerve blocks and ablation.

Managing deepsea oil spills through a systematic modeling approach.

Offshore oil exploration and production in deepwater are associated with environmental risks to marine ecosystems. This research introduces DWOSM (Deep Water Oil Spill Model), a three-dimensional Lagrangian model, which is developed to simulate the transport and fate of oil spills resulting from subsea blowouts. DWOSM comprises three interconnected modules: DWOSM-DSD, which predicts the oil droplet size distribution from a blowout release; DWOSM-NearField, simulating plume dynamics and tracking oil droplets within the plume region; and DWOSM-FarField, modeling the evolution of dispersed oil beyond the near-field. Compared to other oil spill models, this integrated approach improves the transition between near and far fields using a near-field particle tracking algorithm. It also employs the thermodynamic models to enable the prediction of oil properties under varying deep water pressure and temperature. To gauge the reliability and efficacy of DWOSM, a hypothetical case situated within a North American context is employed for model testing. The DWOSM and its each module are juxtaposed with other established oil spill models. The outcomes indicate that DWOSM yields comparable results to these models by providing reasonable predictions of a deepwater blowout. The model's verification through case scenario testing and comparison underscores its potential as a decision tool for assessing and managing the potential environmental impacts of offshore petroleum activities.

Current Issues With Pediatric Cochlear Implantation.

Cochlear implants (CIs) have demonstrated a clear functional benefit in children with severe-to-profound sensorineural hearing loss (SNHL) and thus have gained wide acceptance for treating deafness in the pediatric population. When evaluating young children for cochlear implantation, there are unique considerations beyond the standard issues addressed during surgery in adults. Because of advances in genetic testing, imaging resolution, CI technology, post-implant rehabilitation, and other factors, issues related to CI surgery in children continue to evolve. Such factors have led to changes in candidacy guidelines, vaccine requirements, and lowering of age requirement for surgery. In addition, differences in the anatomy and physiology of infants require special attention to ensure safety when operating on young children. This review summarizes these issues and provides guidance for surgeons treating children with SNHL.

Validity and measurement equivalence of EQ-5D-5L questionnaire among heart failure patients in Malaysia: a cohort study.

AIM: This study aimed to examine the validity of EQ-5D-5L among HFrEF patients in Malaysia, and to explore the measurement equivalence of three main language versions. METHODS: We surveyed HFrEF patients from two hospitals in Malaysia, using Malay, English or Chinese versions of EQ-5D-5L. EQ-5D-5L dimensional scores were converted to utility scores using the Malaysian value set. A confirmatory factor analysis longitudinal model was constructed. The utility and visual analog scale (VAS) scores were evaluated for validity (convergent, known-group, responsiveness), and measurement equivalence of the three language versions. RESULTS: 200 HFrEF patients (mean age = 61 years), predominantly male (74%) of Malay ethnicity (55%), completed the admission and discharge EQ-5D-5L questionnaire in Malay (49%), English (26%) or Chinese (25%) languages. 173 patients (86.5%) were followed up at 1-month post-discharge (1MPD). The standardized factor loadings and average variance extracted were ≥ 0.5 while composite reliability was ≥ 0.7, suggesting convergent validity. Patients with older age and higher New York Heart Association (NYHA) class reported significantly lower utility and VAS scores. The change in utility and VAS scores between admission and discharge was large, while the change between discharge and 1MPD was minimal. The minimal clinically important difference for utility and VAS scores was ±0.19 and ±11.01, respectively. Malay and English questionnaire were equivalent while the equivalence of Malay and Chinese questionnaire was inconclusive. LIMITATION: This study only sampled HFrEF patients from two teaching hospitals, thus limiting the generalizability of results to the entire heart failure population. CONCLUSION: EQ-5D-5L is a valid questionnaire to measure health-related quality of life and estimate utility values among HFrEF patients in Malaysia. The Malay and English versions of EQ-5D-5L appear equivalent for clinical and economic assessments.

EQ-5D is the most commonly used questionnaire to measure patients' health-related quality of life in clinical trials and health technology assessments. To increase confidence over clinical trial findings that heart failure interventions improve health-related quality of life and quality-adjusted life years (number of years alive with equivalence health-related quality of life), the questionnaire used to measure health-related quality of life needs to be validated in the specific population. Since EQ-5D-5L has not been validated in Malaysia's heart failure with reduced ejection fraction (HFrEF) population, this study evaluated the psychometric properties (validity) of EQ-5D-5L among HFrEF patients in Malaysia and the equivalence of different versions of languages (i.e. Malay, Chinese and English) of EQ-5D-5L in measuring the health-related quality of life. The findings suggested that EQ-5D-5L is a valid questionnaire to measure the health-related quality of life in HFrEF patients and estimate the quality-adjusted life years. The Malay and English versions of EQ-5D-5L appear to be equivalent for use in clinical trials and health technology assessments.

Effect of nanobubbles on the mobilization of microplastics in shorelines subject to seawater infiltration.

The widespread presence of microplastics (MPs) in the ocean has varying degrees of impact on ecosystems and even human health. Coastal tidal zones are crucial in controlling the movement of MPs, which are influenced by waves and tidal forces. Meanwhile, natural nanobubbles (NBs) in the ocean can affect the hydrodynamic properties of the tidal zone. The mobilization of MPs in coastal tidal zones under the effect of NBs has been less studied. In this study, we explored natural NBs' influence on the mobilization of MPs in shorelines subject to seawater infiltration. Using glass beads as a substrate, a coastal porous environment was constructed through column experiments, and the pump-controlled water flow was used to study the transport of MPs subject to seawater movement within the substrate. The infiltration of MPs under continuous and transient conditions, as well as the upward transport induced by flood tide, were considered. The role of salinity in the interactions between NBs, MPs, and substrates was evaluated. Salinity altered the energy barriers between particles, which in turn affected the movement of MPs within the substrate. In addition, hydrophilic MPs were more likely to infiltrate within the substrate and had different movement patterns under continuous and transient flow conditions. The motion of the MPs within the substrate varied with flow rate, and NBs limited the vertical movement of MPs in the tidal zone. It was also observed that NBs adsorbed readily onto substrates, altering the surface properties of substrates, particularly their ability to attach and detach from other substances.

Estimation and reduction of bias in self-controlled case series with non-rare event dependent outcomes and heterogeneous populations.

The self-controlled case series (SCCS) is a commonly adopted study design in the assessment of vaccine and drug safety. Recurrent event data collected from SCCS studies are typically analyzed using the conditional Poisson model which assumes event times are independent within-cases. This assumption is violated in the presence of event dependence, where the occurrence of an event influences the probability and timing of subsequent events. When event dependence is suspected in an SCCS study, the standard recommendation is to include only the first event from each case in the analysis. However, first event analysis can still yield biased estimates of the exposure relative incidence if the outcome event is not rare. We first demonstrate that the bias in first event analysis can be even higher than previously assumed when subpopulations with different baseline incidence rates are present and describe an improved method for estimating this bias. Subsequently, we propose a novel partitioned analysis method and demonstrate how it can reduce this bias. We provide a recommendation to guide the number of partitions to use with the partitioned analysis, illustrate this recommendation with an example SCCS study of the association between beta-blockers and acute myocardial infarction, and compare the partitioned analysis against other SCCS analysis methods by simulation.

A multi-criteria simulation-optimization coupling approach for effective emergency response in marine oil spill accidents.

Effective marine oil spill responses are vital to reduce environmental, societal, and economic damage. This study developed a Multi-Criteria Emergency Response System (MC-ERS) to comprehensively evaluate response efficiency, operational costs, and environmental losses. The proposed system integrates dynamic multiphase simulation of oil weathering and oil cleanup processes and further provides effective planning for multi-stage resource allocation through system optimization. The developed weight-sum model improved the performance of response operations by reducing the complexity of multi-criteria decision-making. Particle Swarm Optimization (PSO) was chosen as the foundational optimization algorithm due to its efficiency in rapid convergence and suitability for complex problems. From extensive comparisons of PSO variants across benchmark functions and inertia strategies, the C-PSO algorithm was developed, demonstrating enhanced optimization performance for MC-ERS. The developed modelling system performance was demonstrated and evaluated through a representative case study. The optimization plan coordinated resource allocation from onshore warehouses to harbors and spill sites, balancing oil recovery efficiency, costs, and ecological losses. Optimized results indicate an oil recovery of up to 76.50% in five days. Additionally, the system cuts costs by 3.45% and environmental losses by 15.75%. The findings enhance the efficiency of marine oil spill emergency response and provide support for such incidents.

An alphacoronavirus polymerase structure reveals conserved replication factor functions.

Coronaviruses are a diverse subfamily of viruses containing pathogens of humans and animals. This subfamily of viruses replicates their RNA genomes using a core polymerase complex composed of viral non-structural proteins: nsp7, nsp8 and nsp12. Most of our understanding of coronavirus molecular biology comes from betacoronaviruses like SARS-CoV and SARS-CoV-2, the latter of which is the causative agent of COVID-19. In contrast, members of the alphacoronavirus genus are relatively understudied despite their importance in human and animal health. Here we have used cryo-electron microscopy to determine structures of the alphacoronavirus porcine epidemic diarrhea virus (PEDV) core polymerase complex bound to RNA. One structure shows an unexpected nsp8 stoichiometry despite remaining bound to RNA. Biochemical analysis shows that the N-terminal extension of one nsp8 is not required for in vitro RNA synthesis for alpha- and betacoronaviruses. Our work demonstrates the importance of studying diverse coronaviruses in revealing aspects of coronavirus replication and identifying areas of conservation to be targeted by antiviral drugs.

Medicines Regimens Charted for Older People Living in Residential Aged Care: A Repeated Cross-Sectional Study Describing the Number of Medicines, Regimen Complexity, High-Risk Prescribing, and Potential Underprescribing.

OBJECTIVE: We aimed to explore medicines regimens charted for older people living in residential aged care facilities (RACFs). DESIGN: Repeated cross-sectional study using routinely collected data sampled in a cross-sectional manner at 11 time points (day of admission, then at 1, 3, 7, 14, and 30 days, and 3, 6, 12, 18, and 24 months post admission). SETTING AND PARTICIPANTS: The cohort is set in 34 RACFs managed by a single Australasian provider. People aged ≥65 years admitted to permanent care between January 1, 2017, and October 1, 2021, with medicines charted on the date of admission. METHODS: Medicines charted were evaluated for potentially suboptimal prescribing including number of medicines, high-risk prescribing (eg, potentially inappropriate medicines, anticholinergic burden), and potential underprescribing. RESULTS: The 3802 residents in the final cohort had a mean age of 84.9 ± 7.2 years at admission. At least 1 example of suboptimal prescribing was identified in 3479 (92%) residents at admission increasing to 1410 (97%) at 24 months. The number of medicines charted for each resident increased over time from 6.0 ± 3.8 regular and 2.8 ± 2.7 as required medicines at admission to 8.9 ± 4.1 regular and 8.1 ± 3.7 as required medicines at 24 months. Anticholinergic drug burden increased from 1.6 ± 2.4 at admission to 3.0 ± 2.8 at 24 months. Half the residents (2173; 57%) used at least 1 potentially inappropriate medicine at admission, which rose to nearly three-quarters (1060; 73%) at 24 months admission. CONCLUSION AND IMPLICATIONS: The total number of medicines charted for older adults living in RACFs increases with length of stay, with charted as required medicines nearly tripling. Effective interventions to optimize medicines use in this vulnerable population are required.

Pharmacists working in residential aged care: a survey of pharmacist interest and perceived preparedness.

BACKGROUND: Pharmacists involvement in residential aged care facilities has traditionally been limited to that of an external contractor providing medication reviews, or medication supply. AIM: To explore Australian pharmacists' interest and perceived preparedness to work as on-site pharmacists in residential aged care. METHOD: National cross-sectional anonymous online survey open for two weeks (September 17th to October 1st 2022) consisting of Likert-type, multiple choice and multiple selection questions. Australian pharmacists were recruited using a broad advertising strategy which included social and traditional media platforms, and snowball sampling. Data were collected on pharmacist self-reported interest and perceived preparedness to work as on-site aged care pharmacists in residential aged care. Data were analysed using descriptive statistics. RESULTS: Responses were received from 720 participants, 643 were eligible. Most participants were female (n = 466, 73%) and mean (SD) age was 43.5 (SD 12.5) years. Over half the participants were interested or extremely interested in working as an on-site aged care pharmacist (56%, n = 360), and agreed or strongly agreed (n = 475, 76%) that they felt prepared to work as an on-site aged care pharmacist. Most pharmacists felt prepared to engage in a variety of roles within the facilities (> 73% for each role), including resident and system level roles, and the majority agreed they felt prepared to engage with stakeholders, including general practitioners (93%) and medical specialists (86%). CONCLUSION: Pharmacists reported they are interested and feel prepared to work as on-site aged care pharmacists. These findings will inform the roll-out of this new model of care to enhance multidisciplinary collaboration in residential aged care.

Postoperative infectious complications worsen oncologic outcomes following pancreaticoduodenectomy for pancreatic ductal adenocarcinoma.

BACKGROUND: Pancreaticoduodenectomy (PD) remains the only curative option for patients with pancreatic adenocarcinoma (PDAC). Infectious complications (IC) can negatively impact patient outcomes and delay adjuvant therapy in most patients. This study aims to determine IC effect on overall survival (OS) following PD for PDAC. STUDY DESIGN: Patients who underwent PD for PDAC between 2010 and 2020 were identified from a single institutional database. Patients were categorized into two groups based on whether they experienced IC or not. The relationship between postoperative IC and OS was investigated using Kaplan-Meier and Cox-regression multivariate analysis. RESULTS: Among 655 patients who underwent PD for PDAC, 197 (30%) experienced a postoperative IC. Superficial wound infection was the most common type of infectious complication (n = 125, 63.4%). Patients with IC had significantly more minor complications (Clavien-Dindo [CD] < 3; [59.4% vs. 40.2%, p < 0.001]), major complications (CD ≥ 3; [37.6% vs. 18.8%, p < 0.001]), prolonged LOS (47.2% vs 20.3%, p < 0.001), biochemical leak (6.1% vs. 2.8%, p = 0.046), postoperative bleeding (4.1% vs. 1.3%, p = 0.026) and reoperation (9.6% vs. 2.2%, p < 0.001). Time to adjuvant chemotherapy was delayed in patients with IC versus those without (10 vs. 8 weeks, p < 0.001). Median OS for patients who experienced no complication, noninfectious complication, and infectious complication was 33.3 months, 29.06 months, and 27.58 months respectively (p = 0.023). On multivariate analysis, postoperative IC were an independent predictor of worse OS (HR 1.32, p = 0.049). CONCLUSIONS: IC following PD for PDAC independently predict worse oncologic outcomes. Thus, efforts to prevent and manage IC should be a priority in the care of patients undergoing PD for PDAC.

Congenital Cytomegalovirus Testing Outcomes From the ValEAR Trial.

OBJECTIVE: To determine the positivity rate of congenital cytomegalovirus (cCMV) testing among universal, hearing-targeted CMV testing (HT-cCMV) and delayed targeted dried blood spot (DBS) testing newborn screening programs, and to examine the characteristics of successful HT-cCMV testing programs. STUDY DESIGN: Prospective survey of birth hospitals performing early CMV testing. SETTING: Multiple institutions. METHODS: Birth hospitals participating in the National Institutes of Health ValEAR clinical trial were surveyed to determine the rates of cCMV positivity associated with 3 different testing approaches: universal testing, HT-cCMV, and DBS testing. A mixed methods model was created to determine associations between successful HT-cCMV screening and specific screening protocols. RESULTS: Eighty-two birth hospitals were surveyed from February 2019 to December 2021. Seven thousand six hundred seventy infants underwent universal screening, 9017 infants HT-cCMV and 535 infants delayed DBS testing. The rates of cCMV positivity were 0.5%, 1.5%, and 7.3%, respectively. The positivity rate for universal CMV screening was less during the COVID-19 pandemic than that reported prior to the pandemic. There were no statistically significant drops in positivity for any approach during the pandemic. For HT-cCMV testing, unique order sets and rigorous posttesting protocols were associated with successful screening programs. CONCLUSION: Rates of cCMV positivity differed among the 3 approaches. The rates are comparable to cohort studies reported in the literature. Universal CMV prevalence decreased during the pandemic but not significantly. Institutions with specific order set for CMV testing where the primary care physician orders the test and the nurse facilitates the testing process exhibited higher rates of HT-cCMV testing.

Ultrasound shear wave seeds reduced following hamstring strain injury but not after returning to sport.

OBJECTIVES: The purpose of the study was to investigate differences in ultrasound shear wave speed (SWS) between uninjured and injured limbs following hamstring strain injury (HSI) at time of injury (TOI), return to sport (RTS), and 12 weeks after RTS (12wks). METHODS: This observational, prospective, cross-sectional design included male and female collegiate athletes who sustained an HSI. SWS imaging was performed at TOI, RTS, and 12wks with magnetic resonance imaging. SWS maps were acquired by a musculoskeletal-trained sonographer at the injury location of the injured limb and location-matched on the contralateral limb. The average SWS from three 5 mm diameter Q-boxes on each limb were used for analysis. A linear mixed effects model was performed to determine differences in SWS between limbs across the study time points. RESULTS: SWS was lower in the injured limb compared to the contralateral limb at TOI (uninjured - injured limb difference: 0.23 [0.05, 0.41] m/s, p = 0.006). No between-limb differences in SWS were observed at RTS (0.15 [-0.05, 0.36] m/s, p = 0.23) or 12wks (-0.11 [-0.41, 0.18] m/s, p = 0.84). CONCLUSIONS: The SWS in the injured limb of collegiate athletes after HSI was lower compared to the uninjured limb at TOI but not at RTS or 12 weeks after RTS. CRITICAL RELEVANCE STATEMENT: Hamstring strain injury with structural disruption can be detected by lower injured limb shear wave speed compared to the uninjured limb. Lack of between-limb differences at return to sport may demonstrate changes consistent with healing. Shear wave speed may complement traditional ultrasound or MRI for monitoring muscle injury. KEY POINTS: • Ultrasound shear wave speed can non-invasively measure tissue elasticity in muscle injury locations. • Injured limb time of injury shear wave speeds were lower versus uninjured limb but not thereafter. • Null return to sport shear wave speed differences may correspond to structural changes associated with healing. • Shear wave speed may provide quantitative measures for monitoring muscle elasticity during recovery.

Diffusion tensor imaging of hamstring muscles after acute strain injury and throughout recovery in collegiate athletes.

OBJECTIVE: To identify the region of interest (ROI) to represent injury and observe between-limb diffusion tensor imaging (DTI) microstructural differences in muscle following hamstring strain injury. MATERIALS AND METHODS: Participants who sustained a hamstring strain injury prospectively underwent 3T-MRI of bilateral thighs using T1, T2, and diffusion-weighted imaging at time of injury (TOI), return to sport (RTS), and 12 weeks after RTS (12wks). ROIs were using the hyperintense region on a T2-weighted sequence: edema, focused edema, and primary muscle injured excluding edema (no edema). Linear mixed-effects models were used to compare diffusion parameters between ROIs and timepoints and limbs and timepoints. RESULTS: Twenty-four participants (29 injuries) were included. A significant ROI-by-timepoint interaction was detected for all diffusivity measures. The edema and focused edema ROIs demonstrated increased diffusion at TOI compared to RTS for all diffusivity measures (p-values < 0.006), except λ1 (p-values = 0.058-0.12), and compared to 12wks (p-values < 0.02). In the no edema ROI, differences in diffusivity measures were not observed (p-values > 0.82). At TOI, no edema ROI diffusivity measures were lower than the edema ROI (p-values < 0.001) but not at RTS or 12wks (p-values > 0.69). A significant limb-by-timepoint interaction was detected for all diffusivity measures with increased diffusion in the involved limb at TOI (p-values < 0.001) but not at RTS or 12wks (p-values > 0.42). Significant differences in fractional anisotropy over time or between limbs were not detected. CONCLUSION: Hyperintensity on T2-weighted imaging used to define the injured region holds promise in describing muscle microstructure following hamstring strain injury by demonstrating between-limb differences at TOI but not at follow-up timepoints.

Preoperative Ultrasound-Guided Localization of the Lateral Femoral Cutaneous Nerve: From Guide Wire to Novel Clip.

BACKGROUND AND OBJECTIVE: Lateral femoral cutaneous nerve (LFCN) decompression and transposition are surgical treatment options for meralgia paresthetica. Identifying the LFCN during surgery may be challenging, and preoperative localization is a valuable adjunct in this case. The objective of this study was to explore a new technique using preoperative ultrasound-guided clip localization (USCL) of the LFCN. METHODS: After Institutional Review Board approval, data were collected on patients who underwent both preoperative ultrasound-guided wire localization (USWL) and USCL over the past 13 years. Skin-to-nerve time was calculated prospectively. RESULTS: Fifty-six patients were identified, 51 had USWL and 5 had USCL; the skin-to-nerve median time was 7.5 and 6 minutes, respectively. Six wires were misplaced, and this was at the beginning of utilization of the USWL technique. There were no nerve injury, infection, or bleeding complications related to either wire or clip placement. CONCLUSION: USWL or USCL is safe and time-efficient in LFCN surgeries.

Association of quantitative diffusion tensor imaging measures with time to return to sport and reinjury incidence following acute hamstring strain injury.

Hamstring strain injuries (HSI) are a common occurrence in athletics and complicated by limited prognostic indicators and high rates of reinjury. Assessment of injury characteristics at the time of injury (TOI) may be used to manage athlete expectations for time to return to sport (RTS) and mitigate reinjury risk. Magnetic resonance imaging (MRI) is routinely used in soft tissue injury management, but its prognostic value for HSI is widely debated. Recent advancements in musculoskeletal MRI, such as diffusion tensor imaging (DTI), have allowed for quantitative measures of muscle microstructure assessment. The purpose of this study was to determine the association of TOI MRI-based measures, including the British Athletic Muscle Injury Classification (BAMIC) system, edema volume, and DTI metrics, with time to RTS and reinjury incidence. Negative binomial regressions and generalized estimating equations were used to determine relationships between imaging measures and time to RTS and reinjury, respectively. Twenty-six index injuries were observed, with five recorded reinjuries. A significant association was not detected between BAMIC score and edema volume at TOI with days to RTS (p-values ≥ 0.15) or reinjury (p-values ≥ 0.13). Similarly, a significant association between DTI metrics and days to RTS was not detected (p-values ≥ 0.11). Although diffusivity metrics are expected to increase following injury, decreased values were observed in those who reinjured (mean diffusivity, p = 0.016; radial diffusivity, p = 0.02; principal effective diffusivity eigenvalues, p-values = 0.007-0.057). Additional work to further understand the directional relationship observed between DTI metrics and reinjury status and the influence of external factors is warranted.