The authors used population-based data focused on a 30-year cohort of children with acquired nonaccommodative esotropia (ANAET) to report on the presenting features, management and long-term outcomes of this condition. The data demonstrated that ANAET is rare and most children achieve good outcomes. It also suggests it is rarely associated with underlying neurologic malignancy.
The authors conducted a retrospective chart review of all residents of Olmsted County, Minn., under the age of 19 who were diagnosed with ANAET between 1965 and 1994. It showed that 174 children were diagnosed with ANAET, yielding an incidence of 1 in 287 live births - a figure that did not change significantly over the 30-year study period. The condition was most common among males, 61 percent were male (P = 0.009), and the median age at diagnosis was 4 years.
Almost three-quarters of those who underwent surgery were well-aligned after a mean follow-up of 10.9 years, and most had measurable stereopsis-including 6 percent with a functional cure. Patients who were older than 44 months at diagnosis (P = 0.005), and without amblyopia at their initial examination (P < 0.001) were more likely to achieve excellent final stereopsis.
The authors note that ANAET has been traditionally considered a rare form of strabismus. However, it was diagnosed relatively frequently in this cohort, which is consistent with recent reports in which it was the second most prevalent form of esotropia, accounting for 14.4 percent to 16.67 percent of all forms of childhood esotropia.
Although 11 percent presented with diplopia, none of the 174 was later diagnosed with a central nervous system lesion, leading the authors to conclude that while there are case reports of children presenting with ANAET as the initial manifestation of a brain tumor, such an occurrence is sufficiently rare that brain imaging of all patients presenting with ANAET may not be justified.
Clinical experience suggests that imaging is indicated in the subset of patients with ANAET who have characteristics suggestive of an underlying intracranial process, such as lateral incomitance, a greater deviation at distance compared with near and the presence of focal neurologic deficits. However, further research is warranted to identify which children with ANAET are at the greatest risk for harboring a central nervous system lesion.