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

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.

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.

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).

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.