Is Video-Oculography a Predictive Test for Myasthenia Gravis with Ocular Symptoms?

Abstract

Background and objective: The aim of this study was to evaluate the contribution of extraocular muscle function testing with video-oculography (VOG), which is a noninvasive and easily applicable method of recording eye movement with digital cameras, to the diagnosis of myasthenia gravis (MG) in patients without any clinical eye movement abnormalities.

Methods and materials: The study included 18 patients prediagnosed with ocular MG: MG Group (N = 7) with abnormal, and non-MG Group (N = 11) with normal single-fiber electromyography. Control group included 50 healthy volunteers. Ocular movements were recorded with the EyeSeeCam VOG device.

Results: The inward latency of the 10° horizontal saccade and the downward latency of the 10° vertical saccade were significantly delayed; and the downward amplitude of the 10° vertical saccade was significantly lower in the MG group. Receiver operating characteristic curve analyses showed high specificity values for the discrimination of MG patients.

Conclusions: This study supports the usefulness of the VOG device in revealing subclinical extraocular muscle involvement in MG.

Keywords: Eye movements; myasthenia gravis; neuromuscular junction; ocular myasthenia; video-oculography.