Bedside Transorbital Ultrasound in the Clinical Evaluation of Pediatric Optic Neuritis in the Emergency Department.

BACKGROUND

Headache and monocular visual disturbance are worrisome pediatric presenting complaints in the emergency department. Appropriate and timely initial evaluation is critical. Most would opt for urgent computer tomography in such cases. Pediatric optic neuritis is a rare condition and is better evaluated by magnetic resonance imaging. With the increase in the use and scope of bedside ultrasound, there might be a potential role for transorbital ultrasound to be part of the emergency department evaluation of pediatric optic neuritis.

CASE REPORT

This is the first pediatric case report on the use of bedside transorbital ultrasound in the emergency department evaluation of a 15-year-old girl with optic neuritis who presented with unilateral headache and left visual disturbance. Transorbital ultrasound of her left eye revealed an irregularly enlarged optic nerve sheath with increased optic nerve sheath diameter (5.1 mm) and an elevated optic disc height (0.5 mm). Ultrasound examination of her right eye was contrastingly normal, showing an optic nerve sheath diameter of 3.8 mm and that the optic disc was not elevated. The ultrasound findings correlated well with her magnetic resonance imaging of her orbits. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: The clinical findings and monocular ultrasound abnormalities facilitated the emergency department decision-making process and choice of neuroimaging. This highlights the use of transorbital ultrasound as a clinical adjunct and potential role in the emergency department clinical evaluation of a pediatric patient with optic neuritis. The finding of an irregularly enlarged optic nerve might be of potential clinical value but further studies are required.