2116 Post keratoplasty refractive errors and tangential versus sagittal corneal topography

Purpose. The purpose of this study ws~s to evaluate We changes of the refractive error in the follow up after penetrating keratoplasty for Fuchs’ dystrophy. Methods. Between 1960 and 1991 16.2 keratoplasties with mechanical trephination and single running suture ware performed for Fuchs’ dystrophy consecutively. The suture was removed 20,4 f 7.5 months postoperatively. In 99 eyes a simultaneous cataract extraction and posterior chamber lens implantation was performed. The refractive power of the intraocular lens was choosen like in standard cataract surgery without keratoplasty. Results. In eyes without simultaneous intraocular lens implantation the refractive error was +0,5 f 1,9 dpt preoperatively. +3,1 f 4,7 after 6 months, +2,1 f 4.4 after 1 year -0,6 f :3,7 after 2 years, -2.2 f 3.2 after 3 years and -1,6 f 3,7 after 5 years. In eyes with simultaneous posterior chamber lens implantaUon the refractive error was -1,6 f 4.9 dpt preoperatively, -0,4 f 4,4 after 6 months, +O,l f 4,7 afler 1 year -1,l + 4,5 after 2 years, -2.5 i 53 afler 3 years and -3.9 f 7,0 afler 5 years. The difference between refractive error and the refractive prognosis preoperatively estimated by a-scan, was +1,4 dpt after 6 months and 2,0 dpt after 5 years. Conclusion. In the follow up after keratoplasty with mechanical trephination and single running suture for Fuchs’dystrophy there is a myopic shift in the refractive error. This myopisation occures at the time of suture removal. There is a stabilizalion of the refractive error 3 to 4 years postoperatively. This myopisation has to be taken in account in refractive prognosis in cases of simultaneous lens implantation.