Validation of a Low-cost Optic Nerve Sheath Ultrasound Phantom: An Educational Tool

Objective: To validate an ocular phantom as a realistic educational tool utilizing in vivo and phantom optic nerve sheath (ONS) images obtained by ultrasound. Methods: This prospective study enrolled 51 resident physicians from the Denver Health Residency in Emergency Medicine (EM) and 10 ultrasound fellowship-trained EM attending physicians. Participants performed optic nerve sheath diameter (ONSD) measurements on five in vivo and five phantom ocular ultrasound images and rated the realism of each image on a 5-point Likert scale. Chi-square analysis was performed to evaluate the subjective “realness” of in vivo and phantom images. Results: Sixty-one participants performed ONSD measurements. Mean Likert scale values were 3.43 (95% confidence interval: 3.31–3.55) for in vivo images and 3.41 (95% confidence interval: 3.28–3.54) for phantom images. There was no statistical difference in subjective “realness” between in vivo and phantom ONSD ultrasound images among EM residents. Ultrasound fellowship-trained EM attending physicians aptly differentiated between in vivo (p