Eight year results of excimer laser correction for irregular astigmatism by linear excimer laser photoablations of the cornea in cases of keratoconus
Wygledowska-Promieńska, D.; Gierek-Ciaciura, S.
Klinika Oczna 102(6): 439-442
2000
ISSN/ISBN: 0023-2157 PMID: 11392806 Document Number: 514060
The purpose of this study was to evaluate changes of the corneal curvature as a result of linear incisions with excimer laser and also to evaluate durability of the achieved effect, including the changes in visual acuity, topographic maps of the corneal curvature and keratometric changes at the location of keratoconus 2, 4, 8, 16, 24 weeks postoperatively. At the First Department and Clinic of Ophthalmology, Silesian Medical School in Katowice, 294 patients went through ophthalmological examinations. 164 patients (187 eyes) with the III degree of keratoconus according to the Amsler scale, including 69 women (77 eyes) and 95 men (110 eyes), were classified for the excimer laser surgery with the method of linear, corneal incisions with MEL-60 (Aesculap-Meditec). The eyes did not tolerate contact lenses at all or because of peripheral location of the keratoconus. The patients were from 16 to 60 years of age (the mean age was 27.9 years). According to the statistical results, there were no difference between the effects of treatment between men and women. Correlation between the results of the surgery and the patients age showed that the latter did not have any effect on the final result. Lack of correlation between the height of the absolute corneal curvature at the keratoconus and the achieved change after the surgery was reported, thus changes of the corneal curvature parameters do not depend on its parameters before the surgical procedure. Absolute visual acuity of patients was improving and reached maximally 0.252 of the unit. As a result of the single surgery, the maximum change of keratometric values was 4.949 D, and the minimum was 3.611 D. In the case of the secondary surgery, the maximum keratometric value at the axis of the incision was 8.55 D and the minimum one was 7.101 D. To sum up, we can say that the favourable effect of decreasing the irregular corneal astigmatism with the method of linear laser fotoablations was maintained throughout the whole observation period, which allowed to shift in time planned corneal transplantation.