Astigmatismusreduktion durch 4 mm langen nahtfreien kornealen Starschnitt (Stretch-Inzision) mit Phakoemulsifikation und 5 mm PMMA-Linsen-Implantation

Abstract

Refractive cataract surgery using corneal incisions is aiming at neutralization of preoperative astigmatism. 61 patients with preoperative astigmatism of 2.25 +/- 0.98 were included in the treatment. A self-sealing corneal tunnel incision measuring 4.0 to 4.1 mm in external diameter and 6.5 to 7.0 mm in internal diameter (stretch incision) was performed on the steeper axis. After capsulorhexis and phacoemulsification a 5 mm PMMA lens was implanted without suturing. Keratometry and corneal topography were performed preoperatively, 3 days and 1 year respectively following surgery. The statistical analysis was based on the Wilcoxon signed ranks test. Surgical induced astigmatism (IA) following superior incisions in cases of astigmatism with the rule (n = 29) amounted to 1.93 +/- 0.97, while lateral incisions in cases of astigmatism against the rule (n = 29) led to an IA of 1.35 +/- 0.73. Axial shifts by more than 30 degrees were 23% following superior incisions and 17%, after lateral incisions. We observed. astigmatic reduction of 1.3 D after superior incisions and 0.7 D following lateral incisions. By 4 mm corneal cataract incisions on the steeper axis a high preoperative astigmatism can be reduced significantly without additional keratotomies.