Postoperative Refractive Error by Using A-scan in Cataract Surgery After Vitrectomy

ABSTRACT

PURPOSE: To investigate the difference between target refraction and actual refraction of intraocular lens implantation when cataract surgery was performed after vitrectomy. METHODS: This study evaluated 28 eyes of 28 patients who had undergone vitrectomy without gas tamponade and 25 eyes of 25 patients who had undergone vitrectomy with gas tamponade. A-scans were performed before the respective cataract and vitrectomy surgeries. Three months after cataract surgery, the actual refraction was measured. To compare the difference between the actual and the target refraction calculated by each A-scan, the refractive prediction error was calculated. It is determined by subtracting the target refraction from the actual refraction. RESULTS: In 28 eyes, the mean refractive prediction error calculated by the A-scan performed before vitrectomy was -0.146+/- 0.901D (diopter, D), and the mean refractive prediction error calculated by an A-scan performed just prior to cataract surgery was -0.228+/-1.011D. The two values were not statistically significant (p=0.653). In 25 eyes, the mean refractive prediction errors calculated by A-scans performed before vitrectomy and cataract surgery were -0.171+/-1.079D, and -0.227+/-0.798D, respectively. There was no statistically significant difference between the two values (p=0.563). CONCLUSIONS: When a cataract surgery was performed after vitrectomy, a precise target refraction could be obtained.