purpose: to report a case who had undergone lasik in his right eye and prk in the fellow eye for correction of equivalent myopia but developed progressive post-operative keratectasia only in the right eye. patient and findings: a 30-year-old man had undergone lasik in right eye 3 years ago for correction of refractive error of -1.75  -1.50@48° and prk in left eye 2 years ago for correction of r...

PURPOSE We investigated higher-order aberrations (HOAs) of the anterior and posterior corneal surfaces in patients with keratectasia after LASIK. METHODS The subjects comprised four groups: 12 eyes with keratectasia after LASIK, 30 eyes following LASIK without keratectasia, 30 keratoconic eyes, and 30 normal eyes. Corneal HOAs due to the anterior and posterior corneal surfaces for 6-mm pupils...

Here we present the case of a 27-year-old woman with benign joint hypermobility (BJHS) syndrome who developed keratectasia after laser in situ keratomileusis (LASIK) in both eyes. Both eyes had identical low Randleman risk factor scores. To our knowledge, this is the first report of such a complication in a patient with BJHS. It highlights our incomplete knowledge of the risk factors for kerate...

An integrated model for keratectasia risk assessment has received much attention over many years. The objective of this article is to propose a more complete, conceptual model by which high risk individuals can be screened, even with no topographic irregularity or corneal thinning. In this model, corneal ectasia results from the fatigue effect of cyclic shear stress and tensile stress, caused b...

To the Editor: It is common knowledge that the biomechanical stability of connective tissue changes during pregnancy, leading to reduced stiffness and increased extensibility. These changes are most probably hormone-induced and, therefore, corneal biomechanics also may change during pregnancy. Five patients who underwent LASIK experienced vision deterioration during pregnancy, which we attribut...

To determine if the residual corneal stromal bed of 250 microm is enough to prevent iatrogenic keratectasia in laser in situ keratomileusis (LASIK), we studied 958 patients who underwent LASIK from April 2000 to October 2003 retrospectively. The estimated probabilities of the residual stromal bed, that was less than 250 microm, were calculated using the published flap thickness data of Moria C&...

To the Editor: In their recent article, Durrie and colleagues1 reported results of lift-flap retreatment after LASIK. The authors concluded that this procedure appears to be effective and is associated with minimal complications. They reported that before reoperation, mean spherical equivalent refraction was -2.34 D (range, -0.67 to -5.75 D). The Summit Apex excimer laser (Summit Technology, Wa...

purpose: to compare keratocyte density in stromal layers of the cornea in keratoconus, post-lasik keratectasia, lasik without keratectasia, and normal corneas by confocal scan. methods: thirty-one unscarred corneas from 22 patients with keratoconus, 24 clear corneas from 17 cases with post-lasik keratectasia, 12 corneas from 7 lasik cases without keratectasia, and 26 corneas from 13 normal subj...