Does Overcorrecting Minus Lens Therapy for Intermittent Exotropia Cause Myopia?

Abstract

OVERCORRECTING minus lens therapy has been recommended as a treatment for intermittent exotropia.^1-3 By fitting myopic spectacles on hyperopic patients, or spectacles that overcorrect the myopia on myopic patients, accommodative convergence will be stimulated. This should reduce the angle or frequency of an exotropic deviation. It is my practice to try overcorrecting minus lens therapy on most patients with intermittent exotropia if they are young enough that the additional accommodation will not be expected to cause symptoms of asthenopia, typically under 7 years of age. I have had the subjective impression that patients undergoing this treatment program appear to become more myopic than other patients. However, because patients with exotropia are more likely to be myopic than esotropic patients, it is possible that this impression is erroneous.^3-6