Postoperative refractive error after simultaneous vitrectomy and cataract surgery

PURPOSE: To evaluate the effect of vitrectomy on postoperative refraction a fter simultaneous vitrectomy and cataract surgery. METHODS: We compared the spread between predicted and actual refractions in 206 eyes after a simultaneous vitrectomy, phacoemulsification, aspiration and acrylic lens insertion (combined surgery group), and in 67 eyes after c ataract surgery only (cataract surgery group) as control. A vitrectomy was performed for diabetic retinopathy in 127 eyes, macular hole in 32 eyes, rh egmatogenous retinal detachment in 16 eyes, branch retinal vein occlusion i n 15 eyes, and other conditions in 26 eyes. In the combined surgery group, 79 eyes had a gas tamponade after insertion of the intraocular lens. RESULTS: The spread between predicted and actual refractions was -0.05 +/- 1.18 diopters (average +/- SD) in the combined surgery group and +0.55 +/- 1.32 D in the cataract surgery group. The actual refractive errors in the c ombined surgery group were found to shift toward myopia when compared with the controls. Among the combined surgery group, 127 eyes without: a gas tam ponade showed a postoperative refractive error of +0.14 +/- 1.11 D, while 7 3 eyes with a gas tamponade demonstrated an error of -0.36 +/- 1.22 D. CONCLUSIONS: Use of a gas tamponade in the combined surgery group increased the myopic change and was thought to have pressed the intraocular lens for ward.