Quantitating the superior visual field loss associated with ptosis.

The effect of blepharoptosis on the superior visual field was assessed using a series of specially designed contact lenses to simulate ptosis in normal subjects. We found a progressive decrease in the superior visual field at the 90 degree vertical meridian, which was proportional to the degree of simulated ptosis. Our results were in close agreement with both a theoretical model and previous clinical observations. These results are important in evaluating patients contemplating ptosis surgery, as well as in visual field testing for neuro-ophthalmic disorders.