Sir,

I read with interest the article by D W Kim et al1 on conservative management for consecutive esotropia (ET) after intermittent exotropia (IXT) surgery.

The authors managed patients with full-time alternate occlusion and/or with a Fresnel prism. Immediate postoperative esodeviation from 8PD to 40PD, the authors used regular spectacles incorporated with a prism or prisms divided to each eye. In our hospital, we also use Fresnel prism to treat postoperative ET. According to our experience, consecutive ET that is ≥20PD after surgery, especially with factor of accommodation, is hard to achieve ocular alignment at 1-year follow-up. In addition, in this study, 19 patients had amblyopia preoperatively and 16 were in younger age stratum. ET may cause suppression, decreased visual acuity and amblyopia. As we all know, visual acuity will decrease with increasing prism power. However, in this paper, some patients wear prisms for several months without newly developed amblyopia. Why patients’ visual acuity was not affected by prisms? Was a training program needed for amblyopia child?