Sensitivity and specificity of Point-of-Care ocular ultrasound for optic neuritis: a hypothesis generating study

Abstract

Purpose: This retrospective study compares point-of-care ocular ultrasound to MRI in order to establish preliminary data for and identify challenges to a multicenter study into the utility of ocular ultrasound for diagnosing optic neuritis. Methods: Our ultrasound archive was queried to identify subjects suspected of having optic neuritis who underwent ocular ultrasound and MRI of the brain or orbit. Blinded ultrasounds were reviewed by ultrasound faculty. The presence of optic disc elevation, optic nerve, or sheath dilation, and overall impression were recorded and compared to MRI results. Sensitivity and specificity of each ultrasound finding and the overall impression, as well as agreement between the raters, were calculated. Results: Sensitivity and specificity of ultrasound for MRI confirmed optic neuritis was 100 % (95 % CI 54.1-100) and 58.3 % (95 % CI 27.7-84.8). Optic nerve sheath diameter had nearly perfect agreement (κ = 0.8828), however agreement on optic disc elevation (κ = 0.5641), nerve diameter (κ = 0.2174), and overall agreement (κ = 0.1818) were moderate, fair, and poor, respectively. Conclusions: This preliminary study estimates test characteristics of ocular ultrasound for the diagnosis of optic neuritis for the purposes of power analysis and to identify potential pitfalls in preparation for a larger prospective investigation.