Stereoacuity after Photorefractive Keratectomy in Anisometropia

To determine changes in streoacuity in anisometropic myopic eyes after photorefractive keratectomy (PRK). This quasi-experimental clinical trial was performed in myopic patients with at least 1 D of in anisometropia spherical, astigmatic or spherical equivalent who underwent photorefractive keratectomy (PRK) using the Technolas 217 Z excimer laser machine. Changes in streoacuity were evaluated. TNO and butterfly stereoacuity tests before PRK and at 2 weeks, 1 month and 3 months after PRK. Overall, 98 eyes of 49 patients (71. 4% male and 28. 6% female subjects) with mean age of 285. 5 years and mean myopia of -3. 321. 74D and mean astigmatism of 1. 31. 3 D were enrolled in study. Preoperative mean stereoacuity values were 102103. 44 sec/arc and 56. 841 sec/arc by TNO and butterfly stereoacuity tests which changed to 90110. 52 sec/arc (P=0. 009)، and 56. 541. 3 sec/arc (P=0. 80) respectively 3 months after PRK. Total proportion of improvement in stereoacuity values was 10. 2% and 6. 12% by TNO and Butterfly Stereoacuity tests respectively. Stereoacuity improves after photorefractive keratectomy in anisometropic myopic patients. This improvement is more significant with TNO test than the Butterfly Stereoacuity test.