INTERNUCLEAR ophthalmoplegia is the hallmark of a lesion in the paramedian pontine tegmentum.1-3 It implies distinctive disturbances in patterns of ocular motor innervation. Electromyography (EMG) was used in six patients with acute and chronic internuclear ophthalmoplegia to display and analyze these altered patterns of motor excitation and inhibition during various types of horizontal gaze. All were patients at the University of California San Francisco Medical Center.
Conjunctival topical anesthesia was used. Fine concentric needle electrodes were inserted into the involved medial rectus (MR) and one or more of the other three horizontal rectus muscles and were gently manipulated until the recording tips were securely within the belly of the muscle. The electronic system used for recordings from these muscles is standard for EMG and has been described previously.4Several types of horizontal eye movements were studied: (1) following movements to the extremes of lateral gaze, (2)
JOHN D. LOEFFLER, WILLIAM F. HOYT, BERNARD SLATT. Motor Excitation and Inhibition In Internuclear PalsyAn Electromyographic Study. Arch Neurol. 1966;15(6):664–671. doi:10.1001/archneur.1966.00470180104012