Stepwise increase of hypermetropic correction using contact lenses in intermittent partially accommodative esotropia

Abstract

Background

The aim was to present a series of patients with intermittent partially accommodative esotropia (pAcc‐ET) in evaluating the effect of over‐plus correcting the hypermetropia relative to the non‐cycloplegic refraction using contact lenses.

Methods

Twenty‐three patients (23.8 ± 8.9-years) with intermittent pAcc‐ET were fitted with soft daily single‐vision contact lenses and the hypermetropia was over‐plus corrected relative to the original subjective non‐cycloplegic refraction, reducing distance visual acuity to 0.8 (decimal acuity). Hypermetropia correction was increased at follow‐ups (every second week) until visual acuity stabilised or symptoms ceased. The contact lenses were worn for the entire study period.

Results

After eight weeks of treatment (two to four follow‐ups) the intermittent esotropia stabilised into esophoria and the magnitude of the deviation at distance was reduced in 70 per cent (16/23) of patients and at near in 91 per cent (21/23) of patients. As a result calculated accommodative‐convergence and the level of accommodation (stimulus AC/A ratio) was reduced in 83 per cent (19/23) of patients but still classified as high (less than 5:1).

Conclusions

Compared to correction based on original non‐cycloplegic subjective refraction, increasing correction of hypermetropia with contact lenses in partially accommodative esotropia reduced the magnitude of the eso‐deviation at distance and near. In addition to reducing accommodative demand and stimulus AC/A with increasing hyperopic correction, contact lenses may provide additional benefit given the increased hyperopic correction and the decreased stimulus for accommodation required at the corneal plane.

Key words:

• accommodation
• contact lenses
• esophoria
• esotropia
• hypermetropia

Acknowledgement

Financial support was received from the Swedish Contact Lens Association (Sveriges Kontaktlinsförening)