Surgical Management in Type 1 Monocular Elevation Deficiency.

Purpose: To evaluate the outcome of surgical treatment in patients with type 1 monocular elevation deficiency.

Methods: Patients who were diagnosed as having type 1 monocular elevation deficiency by forced duction test and exaggerated traction test between 2000 and 2016 were retrospectively reviewed. Epidemiologic and clinical features of the patients were noted. The efficacy of ipsilateral inferior rectus recession to vertical misalignments and limitation of elevation were evaluated. The clinical features of the patients who did not achieve surgical success after inferior rectus recession were determined. The surgical and functional results of contralateral superior rectus recession were evaluated for patients who had residual hypotropia under inferior rectus recession.

Results: Thirty-nine patients were included in the study. Preoperatively, vertical deviations were 20.53 ± 4.50 prism diopters (PD) for near and 22.21 ± 5.12 PD for distance. After inferior rectus recession, the amount of vertical deviation corrected was 15 ± 1.14 PD for near and 17.01 ± 2.00 PD for distance. Ten (25.64%) patients did not achieve surgical success (> 6 PD residual hypotropia). Nine patients (preoperative inferior rectus recession measurements = 28.77 ± 7.25 PD for near and 27 ± 7.44 PD for distance) underwent contralateral superior rectus recession as a second surgery. After contralateral superior rectus recession, 7 of 9 (77.78%) patients achieved surgical success. The limitation of elevation significantly improved after both surgeries (Wilcoxon test, P < .05). No diplopia or other complications after surgeries were reported.

Conclusions: Inferior rectus recession is the first surgical option for patients with type 1 monocular elevation deficiency. Contralateral superior rectus recession is an effective alternative surgical treatment for residual hypotropia after ipsilateral inferior rectus recession. [J Pediatr Ophthalmol Strabismus. 2018;55(6):369-374.].