What is a Saccade?

Abstract

A saccade is a rapid eye movement between two points in space. It can be generated voluntarily or reflexly.

Saccadic eye movements are an objective parameter of extraocular muscle function. Saccadic eye movements are a stress test for the ocular motor system and can be usefully used in the evaluation of this system.

Saccadic velocity measurements are useful in the evaluation of rectus muscle paresis or paralysis. The extent of the weakness can be inferred, even when mechanical restrictions to ocular motility are present. Rectus muscle weakness results in a reduced saccadic velocity in the direction of action of the involved rectus muscle. Mechanical restrictions to eye movement do not reduce saccadic velocity. In various neuro-ophthalmic conditions, the diagnosis can be assisted or confirmed by saccadic velocity studies. Saccadic eye movement measurements can be simple, inexpensive, easily repeatable and applicable to patients of any age. When used properly, the findings can be' of great assistance to the strabismus surgeon.