CONSECUTIVE EXOTROPIA FOLLOWING THE OPTICAL TREATMENT OF ACCOMMODATIVE ESOTROPIA

Carmen Barnhardt

Abstract

BACKGROUND: Consecutive exotropia is an iatrogenic condition where esotropia is initially present then following treatment exotropia occurs due to either an over correction following strabismus surgery or following the optical correction of esotropia. The prevalence of consecutive exotropia among optically treated esotropia is between 10% and 18.4%.

CASE REPORT(S): A 3-year-old girl with behavior problems was referred for amblyopia treatment due to noncompliance with occlusion therapy. Initial findings included visual acuity of 20/30 OD and 20/80 OS, a constant left esotropia of approximately 22pd via Hirschberg through her habitual prescription of +5.25 DS OU and uncrossed diplopia. A cycloplegic refraction revealed +7.25-0.75x180 OD and +7.75-0.75x180 OS. The full-cycloplegic refraction was prescribed for full-time use along with daily atropine OD for amblyopia treatment. Visual acuity and alignment were monitored monthly. As the visual acuity improved to 20/25 OD and 20/40 OS the cover test revealed a 10pd constant left exotropia at far and a 10pd esophoria at near. Sensory fusion testing revealed OS constant suppression at far, fusion at near and no random dot stereopsis. The full cycloplegic refraction was reduced and a bifocal was prescribed. Due to behavior problems there was poor adaptation to the glasses thus noncompliance with full-time wear. Single vision lenses were then prescribed to facilitate compliance with glasses and optimize fusion at both distance and near.

CONCLUSIONS: Typically the full cycloplegic refraction is prescribed for accommodative esotropia. Although uncommon, clinicians need to be aware that consecutive exotropia can occur and monitor their patients over time since this condition can develop several months after the initial hyperopic correction is prescribed. Risk factors reported include a high hyperopic refractive error, a small to moderate sized esotropia, a high AC/A ratio, amblyopia and poor sensory fusion including poor stereopsis and a reduced near point of convergence.

Details

Year: 2004

Program Number: Poster 6

Resource Type: Scientific Program

Author Affiliation: Marshall B. Ketchum University, College of Optometry

Co-Authors: Michael Rouse

Co-Author Affiliation: Marshall B. Ketchum University, College of Optometry

Room: n/a