The application of electrophysiologic techniques to the analysis of ocular motility problems has yielded important information and provided a most useful tool for diagnosis and research in related fields of ophthalmology and neurology.1-3
Our understanding of normal patterns of innervation of the extraocular muscles has been advanced, and considerable insight has been obtained in the altered dynamics of ocular muscle pareses, myopathies, ptosis, myasthenia gravis, comitant strabismus, and nystagmus. The effect of drugs may be readily evaluated.
The technique requires the subconjunctival insertion of fine-gauge concentric electrodes directly into the extraocular muscles, using only topical anesthesia. This is a simple, practical procedure, devoid of harmful effects—the only complication is the occasional occurrence of a subconjunctival ecchymosis which is a cosmetic blemish of brief duration. The muscle potentials are suitably amplified, displayed on dual beam oscilloscopes, and recorded with moving film photography. Extraocular muscle motor units have a duration of
BREININ GM. Electromyography—A Tool in Ocular and Neurologic DiagnosisI. Myasthenia Gravis. AMA Arch Ophthalmol. 1957;57(2):161-164. doi:10.1001/archopht.1957.00930050169001