Superior Oblique Myokymia Associated with Neurovascular Cross Compression

Abstract

Superior oblique myokymia (SOM) is a rare disorder characterized by unilateral paroxysmal oscillopsia or diplopia. Recent studies revealed that SOM can be associated with neuro-vascular cross compression (NVCC) of the trunk of the trochlear nerve. Although it frequently occurs without any underlying systemic disease or concurrent neurologic sign, we need to consider this NVCC especially in cases with persistent disturbing symptoms. Hereby, we present two cases of SOM whose neuroimaging studies suggest NVCCs and, discuss recent update of the pathomechanism of SOM.