The prevalence of strabismus types in strabismic Iranian patients

To determine the frequency of different types of strabismus and amblyopia in the patients of strabismus clinics from 2008 to 2014.

This retrospective cross-sectional study was conducted using data from the archives of Farabi Hospital in Tehran, Iran, from 2008 to 2014. The study consisted of using records of strabismic patients. From these, strabismus types and associated abnormalities, types of amblyopia and other ocular pathological findings were recorded.

In this study, 1174 strabismic patients were studied. Accommodative esotropia (ET) was the most prevalent type of strabismus accounting for 25.04% of all strabismic patients while intermittent exotropia (XT), nonaccommodative ET and partially accommodative ET, with 12.09%, 11.24% and 10.39%, respectively, were relatively common. Also, 63.03% of all strabismic patients had esodeviation with XT coming second accounting for 24.53% of patients. Other ocular pathologic findings in addition to strabismus were found in 236 (20.1%) patients. The most common association with those types of strabismus was inferior oblique over action accounting for 11.07% of all cases, and 88 patients had nystagmus in addition to strabismus. Significantly 45% of patients had no amblyopia and 37% of patients had a combined type of amblyopia which was the most common type of amblyopia found in strabismic patients.

The prevalence of ET was two and a half times more than XT and almost half of strabismic patients suffer from amblyopia. This study suggests that strabismus screening of children could be useful in the early detection of strabismus, appropriate management of it and prevention of strabismic amblyopia.