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Minerva Oftalmologica 2004 March;46(1):77-92

Copyright © 2004 EDIZIONI MINERVA MEDICA

language: English, Italian

Decentrations after refractive surgery with excimer laser: clinical, topographic, aberrometric aspects and techniques of correction

Mastropasqua L., Toto L., Nubile M., Zuppardi E.

Decentration is a rare complication of keratorefractive photoablations procedures that may induce decrement of visual acuity, halos, glare, reduction of contrast sensitivity and irregular astigmatism. Degradation of visual performance is probably related to an increment of high order aberrations and particularly of third order coma-like aberrations caused by the asymmetry of corneal surface at the pupil entrance. Several factors accounts for a decentred ablation and among these the most common are represented by failure to centre the treatment by the surgeon or intraoperative eye movements not effectively compensated by the eye tracker system. Corneal topography and ocular aberrometry represent 2 valid methods for decentration diagnosis on which base several surgical approaches of correction such as arcuate keratotomy, diametral ablations and the new customized topographic and aberrometric ablation techniques.