BACKGROUND: Ultrasound guided regional anesthesia is widely taught using task trainer models. Commercially available models are often used; however, they can be cost prohibitive. Therefore, alternative "homemade" models with similar fidelity are often used. We hypothesize that professional task trainers will be preferred over homemade models. The purpose of this study is to determine realism, durability and cleanliness of three different task trainers for ultrasound guided nerve blocks. METHODS:This was a prospective observational study using a convenience sample of medical student participants in an ultrasound guided nerve block training session on January 24th, 2015. Participants were asked to perform simulated nerve blocks on three different task trainers including, 1 commercial and 2 homemade. A questionnaire was then given to all participants to rate their experiences both with and without the knowledge on the cost of the simulator device.RESULTS: Data was collected from 25 participants. The Blue Phantom model was found to have the highest fi delity. Initially, 10 (40%) of the participants preferred the Blue Phantom model, while 10 (40%) preferred the homemade gelatin model and 5 (20%) preferred the homemade tofu model. After cost awareness, the majority, 18 (72%) preferred the gelatin model. CONCLUSION:The Blue Phantom model was thought to have the highest fidelity, but after cost consideration the homemade gelatin model was preferred.

Introduction Point-of-care ultrasound (POCUS) plays a pivotal role in evaluating ocular complaints in the emergency department (ED). The rapid and non-invasive nature of ocular POCUS makes it a safe and informative imaging modality. Previous studies have investigated using ocular POCUS to diagnose posterior vitreous detachment (PVD), vitreous hemorrhage (VH), and retinal detachment (RD); however, there are few studies that assess image optimization techniques and how they impact the overall accuracy of ocular POCUS. Methods We performed a retrospective review of ED patients who received ocular POCUS examinations and ophthalmology consultations as part of their evaluation for eye complaints at our urban, Level I trauma center ED from November 2017–January 2021. Of 706 exams, 383 qualified for the study. In this study we primarily investigated how stratified gain levels impact the accuracy of ocular POCUS for detection of any posterior chamber pathology and, secondarily, whether stratified gain levels impact the accuracy of detecting RD, VH, and PVD specifically. Results The images were found to have an overall sensitivity of 81% (76–86%), specificity of 82% (76–88%), positive predictive value (PPV) of 86% (81–91%), and negative predictive value (NPV) of 77% (70–83%). Images acquired with a gain of (25, 50] had a sensitivity of 71% (61–80%), specificity of 95% (85–99%), PPV of 96% (88–99%), and NPV of 68% (56–78%). Images acquired with a gain of (50, 75] had a sensitivity of 85% (73–93%), specificity of 85% (72–93%), PPV of 86% (75–94%), and NPV of 83% (70–92%). Images acquired with a high gain (75, 100] had a sensitivity of 91% (82–97%), specificity of 67% (53–79%), PPV of 78% (68–86%), and NPV of 86% (72–95%). Conclusion In the ED setting, high (75, 100] gain on ocular POCUS scanning has a higher degree of sensitivity for detecting any posterior chamber abnormality, as compared to low (25, 50] gain levels. Thus, incorporating the use of high gain for ocular POCUS exams produces a more effective tool for ocular pathologies in acute care settings and may be particularly valuable in resource-limited settings.