Refractive surgery in patients with high myopic anisometropia

To assess the efficacy and safety of LASIK in patients with high myopic anisometropia and to provide specific screening guidelines for anisometropic patients undergoing refractive surgery.

Twenty-six eyes of 16 patients with high myopic anisometropia (>3.0 diopters) were enrolled in this study. Complete pre- and postoperative ophthalmologic and orthoptic examinations were performed. The preoperative orthoptic examination was done with glasses and contact lenses. Twenty-two eyes of 13 patients underwent uncomplicated LASIK; the second eye was treated 2 weeks after the first eye. Patients were examined 1 day, 7 days, and 1, 3, 6, and 12 months after surgery.

Thirteen patients obtaining good results at red glass bar test (RGB) underwent LASIK without postoperative diplopia; four showed an improvement of the sensorial assessment. Three patients were excluded from surgery because of diplopia with RGB values <4 to 5. LASIK temporarily induced diplopia in the suppressed eye of one patient; however, the diplopia disappeared after surgery of the fixating eye.

Patients with high myopic anisometropia and a weak sensorial state who undergo refractive surgery may be at risk for postoperative diplopia. We suggest clinical guidelines to reduce the occurrence of this complication.