Novice emergency physician ultrasonography of optic nerve sheath diameter compared to ophthalmologist fundoscopic evaluation for papilledema

OBJECTIVES: The purpose of this study is to determine the sensitivity and specificity of novice emergency physician‐performed point‐of‐care ultrasound diagnosis of papilledema using optic nerve sheath diameter (ONSD) against ophthalmologist‐performed dilated fundoscopy. This observational study retrospectively analyzed results of ultrasound‐measured ONSD of emergency department (ED) patients with suspected intracranial hypertension from a period spanning June 2014 to October 2017. METHODS: This study concerns a population of ED patients at a large, tertiary‐care urban academic medical center from June 2014 to October 2017 over the age of 18 years with primary vision complaints evaluated for papilledema both by an emergency physician‐performed ultrasound and an ophthalmologist‐performed fundoscopic examination during their ED stay. Sensitivity and specificity of emergency physician‐performed ultrasound measurement of optic nerve sheath diameter in the diagnosis of papilledema were primary outcomes for this study. RESULTS: A total of 206 individual patients (male 49%, female 51%; median age 45 years) were included in the study with a total of 212 patient encounters. Calculated sensitivity for the ocular ultrasound examination performed by emergency physicians to diagnose papilledema was 46.9% (95% confidence interval [CI], 32.5% to 61.7%), and specificity was 87.0% (95% CI, 82.8% to 90.5%). Positive predictive value and negative predictive value were calculated to be 35.4% (95% CI, 23.9% to 48.2%) and 91.5% (95% CI, 87.8% to 94.4%), respectively. CONCLUSIONS: Sonographic measurement of ONSD by emergency physicians has low sensitivity but high specificity for detection of papilledema compared to ophthalmologist‐conducted fundoscopy.