Creation and Validation of a Novel 3-Dimensional Pediatric Hip Ultrasound Model.

OBJECTIVES: The aim of this study was to create and validate a 3-dimensional (3D) ultrasound model with normal and abnormal pediatric hip joint anatomy that is comparable to a pediatric hip joint in appearance and anatomy and replicates sonographic characteristics of a pediatric hip joint. METHODS: A 3D rendering of the bone and soft tissue was created from a computed tomography pelvic scan of a pediatric patient. This rendering was modified to include a unilateral joint effusion. The bone was 3D printed with a photopolymer plastic, whereas the soft tissue was cast with a silicone mixture in a 3D-printed mold. The effusion was simulated by injecting saline into the soft tissue cavity surrounding the bone. The ultrasound model was validated by pediatric point-of-care ultrasonographers at an international pediatric ultrasound conference. RESULTS: A pediatric hip ultrasound model was developed that simulates both normal and abnormal pediatric hip joint anatomy, each with an appropriately sized, measurable joint effusion. Validation by pediatric point-of-care ultrasonographers showed that the key aspects of a normal pediatric hip joint (femoral physis, sloped femoral neck, and adequate soft tissue) with an identifiable and measurable effusion were included in the ultrasound model. CONCLUSIONS: In this study, we successfully created a cost-effective, reusable, and reproducible 3D pediatric hip ultrasound model. The majority of pediatric point-of-care ultrasonographers who evaluated the model agreed that this model is comparable to a pediatric patient for the purpose of teaching ultrasound skills and joint space measurement.

Development and Validation of a Point-of-Care-Ultrasound Image Quality Assessment Tool: The POCUS IQ Scale.

OBJECTIVES: We aimed to develop a standardized scoring tool to measure point-of-care ultrasound (POCUS) image quality and to determine validity evidence for its use to assess lung ultrasound image quality. METHODS: The POCUS Image Quality (POCUS IQ) scale was developed by POCUS-trained physicians to assess sonographers' image acquisition skills by evaluating image quality for any POCUS application. The scale was piloted using lung images of healthy standardized patients acquired by three expert sonographers compared to three novices before and after training. All images (experts, novices pre-training, novices post-training) were scored on the POCUS IQ scale by three blinded POCUS-trained physicians. Reliability was assessed with fully-crossed generalizability and decision studies. Validity was assessed using Messick's framework. RESULTS: Content validity was supported by the tool's development process of literature review, expert consensus, and pilot testing. Response process was supported by reviewer training and the blinded scoring process. Relation to other variables was supported by scores relating to sonographer experience: median expert score = 10.5/14 (IQR: 4), median novice pre-training score = 6/14 (IQR: 2.25), and novices' improvement after training (median post-training score = 12/14, IQR: 3.25). Internal structure was supported by internal consistency data (coefficient alpha = 0.84, omega coefficient = 0.91) and the generalizability study showing the main contributor to score variability was the sonographer (51%). The G-coefficient was 0.89, suggesting very good internal structure, however, Gwet's AC2  was 0.5, indicating moderate interrater reliability. The D study projected a minimum of 1 reviewer and 2 patients are needed for good psychometric reliability. CONCLUSIONS: The POCUS scale has good preliminary validity evidence as an assessment tool for lung POCUS image acquisition skills. Further studies are needed to demonstrate its utility for other POCUS applications and as a feedback tool for POCUS learners.

Point-of-Care Ultrasound, an Unexpected Cardiac Mass in a Neonate.

ABSTRACT: Neonatal cardiac masses are uncommon and often not obvious based on physical examination or plain radiography. The objective of this clinical case report is to demonstrate how cardiac point-of-care ultrasound was pivotal in the clinical course of a seemingly well neonate with vague symptoms. A 6-week-old male infant presented to the emergency department with fatigue and pallor that was reported to have resolved before arrival. In the emergency department, he had a normal physical examination and stable vital signs. Cardiac point-of-care ultrasound was performed and demonstrated a mass near the mitral valve. These ultrasound findings prompted additional evaluation, cardiology consultation, admission, and subsequent diagnosis of a rhabdomyoma due to tuberous sclerosis.

Point-of-Care Ultrasound Assessment of Orbital Rhabdomyosarcoma in a Pediatric Patient.

ABSTRACT: Rhabdomyosarcoma is the most common soft tissue tumor in children and orbital lesions account for 10% of these diagnoses. This case describes a young boy who presented with eyelid swelling that was initially concerning for an expanding hematoma given a history of recent trauma to the eye. Point-of-care ultrasound identified 2 distinct lesions surrounding the globe, which prompted further investigation, including ophthalmology consult and computed tomography. The case presented highlights the initial misdiagnosis on both point-of-care ultrasound and computed tomography and the importance of using color Doppler on ultrasound to distinguish an orbital rhabdomyosarcoma from a posttraumatic hematoma.

Diagnostic Accuracy of Point-of-Care Ultrasound for Intussusception: A Multicenter, Noninferiority Study of Paired Diagnostic Tests.

STUDY OBJECTIVE: To determine the diagnostic accuracy of point-of-care ultrasound (POCUS) performed by experienced clinician sonologists compared to radiology-performed ultrasound (RADUS) for detection of clinically important intussusception, defined as intussusception requiring radiographic or surgical reduction. METHODS: We conducted a multicenter, noninferiority, observational study among a convenience sample of children aged 3 months to 6 years treated in tertiary care emergency departments across North and Central America, Europe, and Australia. The primary outcome was diagnostic accuracy of POCUS and RADUS with respect to clinically important intussusception. Sample size was determined using a 4-percentage-point noninferiority margin for the absolute difference in accuracy. Secondary outcomes included agreement between POCUS and RADUS for identification of secondary sonographic findings. RESULTS: The analysis included 256 children across 17 sites (35 sonologists). Of the 256 children, 58 (22.7%) had clinically important intussusception. POCUS identified 60 (23.4%) children with clinically important intussusception. The diagnostic accuracy of POCUS was 97.7% (95% confidence interval [CI] 94.9% to 99.0%), compared to 99.3% (95% CI 96.8% to 99.9%) for RADUS. The absolute difference between the accuracy of RADUS and that of POCUS was 1.5 percentage points (95% CI -0.6 to 3.6). Sensitivity for POCUS was 96.6% (95% CI 87.2% to 99.1%), and specificity was 98.0% (95% CI 94.7% to 99.2%). Agreement was high between POCUS and RADUS for identification of trapped free fluid (83.3%, n=40/48) and decreased color Doppler signal (95.7%, n=22/23). CONCLUSION: Our findings suggest that the diagnostic accuracy of POCUS performed by experienced clinician sonologists may be noninferior to that of RADUS for detection of clinically important intussusception. Given the limitations of convenience sampling and spectrum bias, a larger randomized controlled trial is warranted.

Development of a novel pediatric point-of-care ultrasound question bank using a modified Delphi process.

BACKGROUND AND OBJECTIVES: Measuring pediatric emergency medicine (PEM) fellow competency in point-of-care ultrasound (POCUS) is important for ensuring adequate training and performance. Assessment may include direct observation, image review, quality assessment, and written examination. The purpose of this study was to develop a pediatric POCUS question bank that could subsequently be used as a POCUS assessment for graduating PEM fellows. METHODS: We organized a 10-person question writing group (QWG). Eight hold expertise in POCUS and two hold expertise in medical education. Members of the QWG created questions within four domains: interpretation/diagnosis (50% of questions), anatomy (30%), physics (10%), and pitfalls (10%). POCUS faculty ascertained content validity and the medical education faculty revised questions for syntax and readability. In 2016, we recruited 31 pediatric POCUS experts. The majority were members of the P2 Network, an international group of experts and leaders in PEM POCUS, to participate in three iterative rounds of a modified Delphi process to review, revise, and establish consensus on the question bank. RESULTS: Thirty-one pediatric POCUS experts participated in the three rounds of the modified Delphi process and evaluated 437 questions developed by the expert panel. Forty-nine percent (n = 216) of the questions were accepted in round 1, 30% (n = 130) in round 2, and 11% (n = 47) in the final round. The final question bank included 393 questions covering 17 pediatric POCUS applications. CONCLUSION: We developed a 393-question bank to aid in the assessment of PEM POCUS competency. Future work includes piloting the questions with PEM fellows to evaluate the response process and implementing the assessment tool to establish a minimum passing score.