AIMS/BACKGROUND Keratoconus is generally held to be an absolute contraindication for photorefractive keratectomy (PRK). Corneas with inferior steepening on corneal topography are widely thought to have subclinical keratoconus. We were not convinced that this is always the case, as there seems to be a group of patients with a stable inferior steepening pattern on topography who show no other cha...

PURPOSE To assess the repeatability of corneal wavefront aberrations derived from Pentacam (Oculus) corneal topography. SETTING Flinders Eye Centre, Flinders Medical Centre, Bedford Park, South Australia, Australia. METHODS Forty-five normal participants and 10 participants with keratoconus were tested. Intraobserver and interobserver repeatability was determined using 4 observers within an...

METHODS: In this consecutive case series, patients underwent phacoemulsification and bilateral or unilateral IOL implantation with the M-flex T IOL (Rayner Intraocular Lenses Ltd.). All underwent refractive assessment and corneal topography preoperatively and postoperatively. Outcome measures included uncorrected distance VA, spherical and cylindrical refraction, and spherical equivalent (SE) (...

Background Photorefractive keratectomy (PRK) is at risk of serious complications such as corneal ectasia, which can reduce corrected distance visual acuity. The rate of complications of PRK is higher in patients with atypical topography. Objective To determine the outcomes of photorefractive keratectomy in patients with atypical topography. Methods This cross-sectional study was done in 201...

This review outlines risk factors of post-laser in situ keratomileusis (LASIK) ectasia that can be detected preoperatively and presents a new metric to be considered in the detection of ectasia risk. Relevant factors in refractive surgery screening include the analysis of intrinsic biomechanical properties (information obtained from corneal topography/tomography and patient's age), as well as t...

PURPOSE To introduce a new convenient and accurate method to measure the angle kappa using ultrasound biomicroscopy (UBM) and corneal topography. METHODS Data from 42 eyes (13 males and 29 females) were analyzed in this study. The angle kappa was measured using Orbscan II and calculated with UBM and corneal topography. The angle kappa of the dominant eye was compared with measurements by Orbs...

PURPOSE To validate the estimation of corneal aberrations from videokeratography against a laser ray tracing technique that measured total eye aberrations, in eyes without keratoconus (ie, cornea-dominated wave aberrations). METHODS We measured total and corneal wave aberrations of three eyes diagnosed with keratoconus by slit-lamp microscopy and corneal topography: two eyes from one patient ...

Case reports of six patients having pre-existing corneal irregularities were prepared. They included patients with keratoconus, hexagonal keratotomy, corneal transplant, LASIK, ABMD and previous penetrating injury. Pre and postoperative refraction and topography were analyzed. All patients received biaspheric IOLs and some received corneal or limbal relaxing incisions at the time of the surgica...

Methods: Patient records were identified from a specialty contact lens practice. Data were obtained from myopic patients who were prescribed Ortho-K wear. Demographic data at baseline included age at commencement of Ortho-K and ethnicity. Clinical data recorded at baseline and at years 1, 2 and 3 included subjective refraction, corneal topography, corneal curvature, axial length, pupil size, an...