Binocular saccadic acceleration in multiple sclerosis

Saccadic conjugacy was quantified with a highly accurate scleral sensorcoil technique. For fixed horizontal saccades, here 10 and 20 deg, ocular peak acceleration values were unequal in both eyes. In five controls the binocular peak acceleration ratio (abducting/adducting eye) ranged from 1.10-1.34 (95% interval). In a group of five patients with definitive multiple sclerosis and internuclear ophthalmoplegia the same ratio was significantly >1.34. The parameter offered an objective means of scaling the extent of an internuclear ophthalmoplegia.