The effect of blepharoptosis on the field of vision.

Upper eyelid position, pupillary diameter, and visual field impairment were measured in 26 eyes with adult-onset blepharoptosis. The magnitude of superior visual field impairment was inversely proportional to the distance between the upper lid margin and the pupillary aperture. The distance between the upper lid and the central corneal reflex was the most useful measurement for predicting visual field impairment. Superior visual field impairment was present when the distance between the upper lid and the central corneal reflex was less than 2.5 mm. Visual field impairment inferiorly, temporally, and nasally occurred when the central corneal reflex was obscured and less than 1.5 mm of the vertical diameter of the pupil was visible. Observation of the relationship between the upper eyelid and the pupillary aperture provides useful information for the performance of accurate diagnostic perimetry, as well as for the management of blepharoptosis.