Corneal topography changes after vitreoretinal surgery

The authors report the results of a prospective study to assess corneal top ography changes after vitreo-retinal surgery procedures. Computer-assisted video-keratography using a Topographic Modeling System-1 (TMS-I) were prosp ectively performed before and after vitreoretinal surgery (vitrectomy with or without scleral buckling) in 12 eyes (patients) with varied vitre-oretin al pathology, including cytomegalovirus (CMV) retinitis, CMV-related retina l detachment, retinal detachment with and without proliferative vitreoretin opathy, trauma, acute retinal necrosis, and macular hole. Preoperative and postoperative surface regularity index (SRI), surface asymmetry index (SAI) , and induced astigmatism were determined. Patients were followed for an av erage of 6 months (range: 2-15 months). Mean preoperative SRI was 0.52 (0.0 5-1.06) and postoperative SRI was 0.73 (0.25-1.36). Mean preoperative SAI w as 0.43 (0.22-0.93) and postoperative SAI was 0.56 (0.21-0.99). Mean induce d astigmatism was 0.7 diopters. Our study suggests that the central corneal optical quality (SRI) and the asymmetricity of the anterior corneal curvat ure (SAI) deteriorates after vitreoretinal surgery.