Treatment of Ocular Pareses

Abstract

The theme of this lecture is the treatment of ocular paresis. I can, therefore, only briefly touch on diagnosis. Ocular paresis is accompanied by the following symptoms:

• 1. The result of paresis of the eye muscles is a Limitation of mobility of the affected eye, a limitation of the monocular field of fixation. The consequence of this limitation is a head turn, since the patient can no longer scrutinize the fixed object if the head is held straight.

• 2. Since in paresis of the eye muscles the visual axes are no longer parallel, the outside world is no longer projected on the customary part of the retina in the squinting eye but on parts which convey a different localisation. This is called diplopia. On the other hand different visual targets are projected on to the foveolae of both eyes. This is called confusion. If the patient looks with the paretic eye, the anomaly of the egocentric localisation produces a false orientation and a past-pointing.

• 3. The diplopia occurs particularly in the direction in which the paretic muscles act. With a right-sided abducens paresis, therefore, when looking to the right. Normal binocular vision may be present in the opposite direction. To take advantage of this diplopia-free vision the patient turns his head. This head turn obeys the rule that the head is turned in the direction in which the paretic muscle would pull the eye.