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

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 degrees horizontal saccade and the downward latency of the 10 degrees vertical saccade were significantly delayed; and the downward amplitude of the 10 degrees 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.