When to treat congenital esotropia.

Nelson: We’re going to discuss when to treat congenital esotropia. A 6-month-old child comes into your office with an esotropia of 65 prism diopters, alternate fixation, and a cycloplegic refraction of +2.50. Dr. Morrison, what is your treatment plan? Morrison: A child who’s clearly alternating fixation has a large angle of deviation that I assume to be an infantile strabismus. My cutoff for prescribing glasses would be +2.50 or +3.00. I would consider trying glasses if the child had any accommodative component and certainly if there was a significant near-distance disparity, but routinely this is a child who would progress to surgery. When you discuss surgical correction of infantile esotropia there are two issues that have generated argument in the past. One is whether you should proceed with early surgery to improve longterm stereopsis potential. The second issue is the stability of the strabismus angle. If you observe a child with infantile strabismus over time, many times the angle will slightly increase, which may be associated with some contraction of the medial rectus muscle. Some have argued waiting until the strabismic angle is stable before proceeding with surgery. My current practice pattern would be to schedule that child for surgery. With a deviation of 65 or less, I would do a bilateral medial rectus recession. I would not do a lateral rectus resection with an angle of 65 in a child younger than 2 years. I would see the child again a week prior to surgery. If the angle was stable or within 10 prism diopters, especially if it was increasing slightly, I would proceed with my regular surgery. If I felt that the angle was significantly less, I would delay the surgery for an additional set of measurements to be sure that the angle is stable. Nelson: Dr. Young, same question. Young: My approach would be similar. I do think you need two examinations to make sure that the alignment is stable. It’s been my experience that some of these children get better. If they come to our office at 3 months of age with a 30-prism diopter esotropia, it’s not terribly uncommon for that angle to be smaller and occasionally zero when they return a few months later. So we do need to make sure the alignment is stable, and the Congenital Esotropia Observational Study (CEOS) showed that we need to proceed with caution for the smaller angles. If the angle is 40 prism diopters or more, the CEOS showed that it’s unlikely to get better on its own. I agree with Dr. Morrison that if the hyperopia is 3 prism diopters or less, glasses for the hyperopia are unlikely to reduce the esotropia significantly. So I would also operate if the angle was stable with two consecutive examinations a month or more apart. Nelson: Dr. Schnall, same question. Schnall: In the congenital esotropia observational study, the largest esotropia they observed to resolve without treatment was 45 diopters. Therefore, you can be fairly confident that this patient’s large esotropia is not going to resolve without surgical treatment. I agree with examining the child a second time and I think you also David G. Morrison, MD, is from the Department of Ophthalmology, Vanderbilt University, Nashville, Tennessee.