Visual and refractive pattern in patients with comitant large angle esotropia

PURPOSE: To evaluate visual acuity, refractive error, and angle of deviation in patients with large-angle esotropia and to investigate age related differences in the magnitude of deviation. METHOD: In this retrospective study, medical records of 370 patients diagnosed with large-angle esotropia (horizontal deviation ≥ 50 prism diopters (Δ)) between 4 and 81 years were reviewed. Data collected included demographic information, corrected distance visual acuity (CDVA), cycloplegic refractive error, and angle of deviation in primary position. Amblyopia severity was categorized as mild, moderate, or severe, and its etiology classified based on clinical findings. RESULTS: The mean age of patients was 28.9 ± 17.77 years, and 61.4% were male. The mean horizontal angle of deviation at distance was 72.2 ± 14.08Δ. The mean CDVA was 0.54 ± 0.55 logMAR in the strabismic eye and 0.14 ± 0.22 logMAR in the nonstrabismic eye (p < 0.001). The mean spherical equivalent (SE) was not significantly different between the strabismic (-0.31 ± 3.77 diopter (D)) and non-strabismic eye (-0.29 ± 3.46 D) (p = 0.9). Strabismic amblyopia was the most common etiology (62%), followed by mixed anisohyperopic + strabismic (17.6%), anisoastigmatic + strabismic (13.4%) and anisomyopic + strabismic amblyopia (7%). Finally, the magnitude of deviation was greater in the middle aged to old population (41 to 81 years) (79.72 ± 16.9 Δ) than in children (4-18 years) (67.72 ± 10.99 Δ) (p < 0.001). CONCLUSION: Large-angle esotropia is associated with significant visual impairments, including strabismic amblyopia, as the predominant factor, emphasizing the need for early diagnosis and individualized and timely intervention to prevent the long-term visual deficits.