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Objectives The purpose of this study was to define and report on the effect of a comprehensive musculoskeletal sonography training program to improve accuracy (sensitivity and specificity) for the diagnosis of rotator cuff tears in relatively inexperienced operators. Methods Before the training program was implemented, radiologists (n = 12) had a mean of 2 years (range, <1–12 years) of experience performing and interpreting musculoskeletal sonography. Pre‐ and post‐training shoulder sonographic results were compared to surgical reports or, in their absence, to shoulder magnetic resonance imaging or computed tomographic arthrographic results if within 2 months of the sonographic examination. A total of 82 patients were included in the pre‐training group (January 2010–December 2011), and 50 patients were included in the post‐training group (January 2012–June 2013). The accuracy, sensitivity, specificity, and positive and negative predictive values were determined for the presence or absence of supraspinatus and infraspinatus tendon tears. Results After implementation of the training program, the sensitivity of sonography for detecting full‐thickness rotator cuff tears increased by 14%, and the sensitivity for detecting partial‐thickness rotator cuff tears increased by 3%. Conclusions Quality improvement programs and acquisition standardization along with ongoing, focused case conferences for the entire care team increased the sensitivity of shoulder sonography for diagnosing both full‐ and partial‐thickness rotator cuff tears, independent of the years of operator experience.

Importance In New Zealand, repeat keratoplasty has become the second leading indication for corneal transplantation. Background To report the indications, outcomes and survival of repeat keratoplasty and evaluate the risk factors for graft failure. Design Retrospective study in a public corneal service. Participants Two hundred nineteen patients undergoing 279 repeat keratoplasty procedures during 1991‐2017. Methods The New Zealand National Eye Bank prospectively collects data on all corneal transplants. This was utilized to identify patients undergoing repeat keratoplasty in Auckland. Clinical records were retrospectively reviewed. Main Outcome Measures Graft survival and visual outcome. Results The repeat keratoplasty technique was penetrating keratoplasty (PK) in 242 cases (86.7%) and endothelial keratoplasty in 37 (13.3%). The most common primary indication was keratoconus (46.6%). The most common indication for repeat keratoplasty was endothelial decompensation (37.6%). For PK performed as a repeat keratoplasty, the median survival in years was 12.0 for first, 3.5 for second and 2.3 for third repeat keratoplasty. Keratoconus had the longest graft survival (median 13.0 years). In surviving grafts, median visual acuity was 6/15 at 1 year and 6/12 at 2 years. On multivariate analysis, regraft number (P = .022), non‐European ethnicity (P = .007), concurrent surgical procedure (P < .0005), lower donor endothelial density (P = .028), previous glaucoma surgery (P < .0005), postoperative raised intraocular pressure (P = .001) and graft rejection (P = .032) were associated with keratoplasty failure. Conclusions and Relevance Repeat keratoplasty survival is affected by multiple interacting factors and prognosis worsens with each subsequent regraft. These results will help guide clinicians in addressing patients' individual risk factors when embarking on repeat corneal transplant surgery.

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The purpose of this study was to assess the repeatability and agreement of horizontal white-to-white (WTW) measurements using 4 different imaging modalities including a slit-scanning elevation topographer, dual rotating Scheimpflug camera and Placido Disc tomographer, Placido Disc topographer, and anterior segment optical coherence (OCT) tomographer. Methods:In this prospective study, 33 eyes of 33 healthy subjects were scanned 3 times using each of the Orbscan IIz, Sirius, Nidek OPD III, and DRI OCT Triton devices and WTW measurements were recorded. Repeatability was assessed using the intraclass correlation coefficient (ICC), and agreement was analyzed using Bland-Altman plots.

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Purpose To assess the agreement and repeatability of horizontal visible iris diameter (HVID) or white-to-white (WTW) measurements between four imaging modalities; combination slit scanning elevation/Placido tomography, infrared biometry, dual rotating scheimpflug camera/Placido tomography, and swept source anterior segment optical coherence tomography (AS-OCT). Methods A prospective study of 35 right eyes of healthy volunteers were evaluated using the Orbscan IIz, IOL Master 700, Galilei G2, and DRI Triton OCT devices. The inter-device agreement and repeatability of HVID/WTW measurements for each device were analysed. Results Mean HVID/WTW values obtained by the Orbscan IIz, IOL Master 700, Galilei G2 and DRI Triton OCT were 11.77 ± 0.40 mm, 12.40 ± 0.43 mm, 12.25 ± 0.42 mm, and 12.42 ± 0.47 mm, respectively. All pairwise comparisons revealed statistically significant differences in mean HVID/WTW measurements (p = <0.01) except for the IOL Master 700—DRI OCT Triton pair (p = 0.56). Mean differences showed that the DRI Triton OCT produced the highest HVID/WTW values, followed by the IOL Master 700, Galilei G2 and Orbscan IIz, respectively. The limits of agreement were large on all device pairs. There was high repeatability for all devices (ICC ≥ 0.980). The highest repeatability was seen in the Galilei G2 (ICC = 0.995) and lowest in the Orbscan IIz (ICC = 0.980). Conclusions The four devices exhibit high repeatability, but should not be used interchangeably for HVID/WTW measurements in clinical practice.

Recent advances in techniques to improve indoor localization accuracy for personnel and asset tracking challenges has enabled wide-spread adoption within the retail, manufacturing, and health care industries. Most currently deployed systems use distance estimates from known reference locations to localize a person or asset using geometric lateration techniques. The distances are determined using one of many radio frequency (RF) based ranging techniques. Unfortunately, such techniques are susceptible to interference and multipath propagation caused by obstructions within buildings. Because range inaccuracies from known locations can directly lead to incorrect position estimates, these systems often require careful upfront deployment design to account for site-specific interference sources. However, the upfront system deployment requirements necessary to achieve high positioning accuracy with RF-based ranging systems makes the use of such systems impractical, particularly for structures constructed of challenging materials or dense configurations. In this paper, we evaluate and compare the accuracy and precision of alternative RF-based devices within a range of indoor spaces composed of different materials and sizes. These spaces range from large open areas such as gymnasiums to confined engineering labs of traditional buildings as well as training buildings at the local Fire Department Training Facility. Our goal is to identify the impact of alternative RF-based systems on localization accuracy and precision specifically for first responders that are called upon to traverse structures composed of different materials and configurations. Consequently, in this study we have specifically chosen spaces that are likely to be encountered by firefighters during building fires or emergency medical responses. Moreover, many of these indoor spaces can be considered hostile using RF-based ranging techniques. We built prototype wearable localization edge devices designed for first responders and characterize both ranging and localization accuracy and precision using alternative transceivers including Bluetooth Low Energy, 433 MHz, 915 MHz, and ultra-wide band. Our results show that in hostile environments, using ultra-wide band transceivers for localization consistently outperforms the alternatives in terms of precision and accuracy.