Clinical profile of patients with monocular elevation deficiency undergoing strabismus surgery

To provide a comprehensive evaluation of the visual, refractive, and strabismic characteristics of patients with monocular elevation deficiency (MED) undergoing strabismus surgery.

The medical records of patients at a single institution who were diagnosed with and underwent surgery for MED were reviewed retrospectively. Visual acuity, refractive error, angle of deviation, abnormal head posture (AHP), presence of ptosis, prevalence of amblyopia and strabismic patterns were analyzed, with MED eyes compared with fellow eyes.

A total of 105 patients were included. Mean cylindrical refractive error was significantly higher in MED eyes compared with fellow eyes (-1.40 ± 1.70 D vs -0.62 ± 1.00 D [P < 0.001]). Mean spherical equivalent was 0.25 ± 2.32 D in MED eyes and 0.66 ± 1.41 D in fellow eyes (P = 0.014). In 67 patients with visual acuity measurements, mean corrected distance visual acuity in MED eyes was significantly worse than in fellow eyes (0.18 ± 0.20 vs 0.05 ± 0.11 logMAR [P < 0.001]). Forty patients (60%) had unilateral amblyopia, 38 in the MED eye. The most common type of deviation was hypotropia alone (50%), followed by hypotropia with exotropia (33%) and hypotropia with esotropia (17%). Pure chin-up was the most frequent type of AHP, in 31 of 36 patients with an AHP (86%). Ptosis in the MED eye was observed in 89 patients (85%).

Our findings highlight the variety of clinical presentations in a relatively large cohort of patients with MED undergoing strabismus surgery.