Using Kane's framework to build an assessment tool for undergraduate medical student's clinical competency with point of care ultrasound.

INTRODUCTION: Point-of-care ultrasonography (POCUS) is a portable imaging technology used in clinical settings. There is a need for valid tools to assess clinical competency in POCUS in medical students. The primary aim of this study was to use Kane's framework to evaluate an interpretation-use argument (IUA) for an undergraduate POCUS assessment tool. METHODS: Participants from Memorial University of Newfoundland, the University of Calgary, and the University of Ottawa were recruited between 2014 and 2018. A total of 86 participants and seven expert raters were recruited. The participants performed abdominal, sub-xiphoid cardiac, and aorta POCUS scans on a volunteer patient after watching an instruction video. The participant-generated POCUS images were assessed by the raters using a checklist and a global rating scale. Kane's framework was used to determine validity evidence for the scoring inference. Fleiss' kappa was used to measure agreement between seven raters on five questions that reflected clinical competence. The descriptive comments collected from the raters were systematically coded and analyzed. RESULTS: The overall agreement between the seven raters on five questions on clinical competency ranged from fair to moderate (κ = 0.32 to 0.55). The themes from the qualitative data were poor image generation and interpretation (22%), items not applicable (20%), poor audio and video quality (20%), poor probe handling (10%), and participant did not verbalize findings (14%). CONCLUSION: The POCUS assessment tool requires further modification and testing prior before it can be used for reliable undergraduate POCUS assessment.

Ocular Filariasis in Human Caused by Breinlia (Johnstonema) annulipapillata Nematode, Australia.

We report a human case of ocular filariasis, caused by a species of Breinlia nematode, from Queensland, Australia. Morphological and molecular evidence indicated that the nematode Breinlia (Johnstonema) annulipapillata, or a closely related taxon, likely transmitted from a macropodid marsupial host was involved, which might represent an accidental finding or an emerging zoonosis.

Artificial intelligence for basal cell carcinoma: diagnosis and distinction from histological mimics.

We trained an artificial intelligence (AI) algorithm to identify basal cell carcinoma (BCC), and to distinguish BCC from histological mimics. A total of 1061 glass slides were collected: 616 containing BCC and 445 without BCC. BCC slides were collected prospectively, reflecting the range of specimen types and morphological variety encountered in routine pathology practice. Benign and malignant histological mimics of BCC were selected prospectively and retrospectively, including cases considered diagnostically challenging for pathologists. Glass slides were digitally scanned to create a whole slide image (WSI), which was divided into patches representing a tissue area of 65,535 µm2. Pathologists annotated the data, yielding 87,205 patches labelled BCC present and 1,688,697 patches labelled BCC absent. The COMPASS model (COntext-aware Multi-scale tool for Pathologists Assessing SlideS) based on Convolutional Neural Networks, was trained to provide a probability of BCC being present at the patch level and the slide level. The test set comprised 246 slides, 147 of which contained BCC. The COMPASS AI model demonstrated high accuracy, classifying WSIs as containing BCC with a sensitivity of 98.0% and a specificity of 97.0%, representing 240 WSIs classified correctly, three false positives, and three false negatives. Using BCC as a proof of concept, we demonstrate how AI can account for morphological variation within an entity, and accurately distinguish from histologically similar entities. Our study highlights the potential for AI in routine pathology practice.

Seven Year Old Male with Tricuspid Endocarditis.

Pediatric endocarditis, a rare entity in developed countries, remains a challenging diagnosis to make in children. We present an uncommon etiology of shortness of breath on exertion (SOBOE) in a 7-year-old male presenting with two weeks of nocturnal fever, malaise and fatigue following a viral prodrome. Point of care ultrasound (POCUS) led to suspicion for a ventricular septal defect (VSD) with tricuspid valve (TV) endocarditis, which was ultimately confirmed by formal echocardiography. This ultrasound diagnosis allowed emergency clinicians to order blood cultures under the suspicion of endocarditis as well as expedited antibiotic treatment.

Ultrasound-Assisted Distal Radius Fracture Reduction.

Introduction Closed reduction of distal radius fractures (CRDRF) is a commonly performed emergency department (ED) procedure. The use of point-of-care ultrasound (PoCUS) to diagnose fractures and guide reduction has previously been described. The primary objective of this study was to determine if the addition of PoCUS to CRDRF changed the perception of successful initial reduction. This was measured by the rate of further reduction attempts based on PoCUS following the initial clinical determination of achievement of best possible reduction. Methods  We performed a multicenter prospective cohort study, using a convenience sample of adult ED patients presenting with a distal radius fracture to five Canadian EDs. All study physicians underwent standardized PoCUS training for fractures. Standard clinically-guided best possible fracture reduction was initially performed. PoCUS was then used to assess the reduction adequacy. Repeat reduction was performed if deemed indicated. A post-reduction radiograph was then performed. Clinician impression of reduction adequacy was scored on a 5 point Likert scale following the initial clinically-guided reduction and following each PoCUS scan and the post-reduction radiograph. Results  There were 131 patients with 132 distal radius fractures. Twelve cases were excluded prior to analysis. There was no significant difference in the assessment of the initial reduction status by PoCUS as compared to the clinical exam (mean score: 3.8 vs. 3.9; p = 0.370; OR 0.89; 95% CI 0.46 to 1.72; p = 0.87). Significantly fewer cases fell into the uncertain category with PoCUS than with clinical assessment (2 vs 12; p = 0.008). Repeat reduction was performed in 49 patients (41.2%). Repeat reduction led to a significant improvement (p < 0.001) in the PoCUS determined adequacy of reduction (mean score: 4.3 vs 3.1; p < 0.001). In this group, the odds ratio for adequate vs. uncertain or inadequate reduction assessment using PoCUS was 12.5 (95% CI 3.42 to 45.7; p < 0.0001). There was no significant difference in the assessment of reduction by PoCUS vs. radiograph. Conclusions PoCUS-guided fracture reduction leads to repeat reduction attempts in approximately 40% of cases and enhances certainty regarding reduction adequacy when the clinical assessment is unclear.

Diagnosis of occult scaphoid fractures: a randomized, controlled trial comparing bone scans to radiographs for diagnosis.

BACKGROUND: Many patients with suspected scaphoid fractures but negative radiographs are immobilized for ≥ 2 weeks and are eventually found to have no fracture. Bone scans are reportedly 99% sensitive for these injuries if done ≥ 72 hours postinjury. OBJECTIVE: The purpose of this study was to determine if early bone scans would allow for shorter cast immobilization periods in patients with suspected scaphoid fractures. METHODS: Twenty-seven patients with clinically suspected scaphoid fractures and negative radiographs were randomized to early diagnosis (bone scan within 3-5 days; n  =  12) or traditional diagnosis (radiographs 10-14 days postinjury; n  =  15). The primary outcome was number of days immobilized in a cast. RESULTS: The mean number of days immobilized was 26 in the traditional group and 29 in the bone scan group. Overall, 6 patients had scaphoid fractures (2 in the traditional diagnosis group and 4 in the bone scan group; p > 0.05), and 8 had other types of fractures. These other types of fractures included four distal radius fractures, two triquetral fractures, one trapezoid fracture, and one hamate fracture. There was no significant difference in the number of other types of fractures between groups. The Kaplan-Meier survival analysis using the log-rank test revealed that there was no statistically significant difference between days immobilized between the radiograph and bone scan groups (p  =  0.38). CONCLUSIONS: The current study suggests that the use of bone scans to help diagnose occult scaphoid fractures does not reduce the number of days immobilized and that the differential diagnosis of occult scaphoid fractures should remain broad because other injuries are common.