PURPOSE To evaluate the accuracy of central corneal power measurements by Scheimpflug imaging (Pentacam) for eyes that had corneal refractive surgery. METHODS This study comprised two groups: a pilot group of 100 eyes with prior hyperopic or myopic LASIK that did not have cataract surgery, and a test group of 41 eyes with prior radial keratotomy (RK) and cataract surgery. In the pilot group, ...

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&...

Additional references are provided by the authors to support their claims. However, the Hashemi and Mehravaran study reported results from only 23 subjects, which is likely underpowered to detect small changes in the posterior surface. Ciolini and Belin investigated a larger dataset but reported amean difference between preoperative andpostoperative changes in the posterior surface without a st...

PURPOSE Despite the proliferation of wavefront sensors to characterize the optical quality of individual eyes, there is not yet an accurate way to determine from a wave aberration how severely it will impact the patient's vision. Some of the most commonly used metrics, such as RMS wavefront error and the Strehl ratio, predict subjective image quality poorly. Our goal is to establish a better me...

The detection of refractive corneal surgery by LASIK, during the storage of corneas in Eye Banks will become a challenge when the numerous operated patients will arrive at the age of cornea donation. The subtle changes of corneal structure and refraction are highly suspected to negatively influence clinical results in recipients of such corneas. In order to detect LASIK cornea interfaces we dev...

UNLABELLED Purpose. To describe a case of 3 refractive procedures performed in one eye over 2 decades. Methods. CASE REPORT Results. A 41-year-old patient presented for refractive surgery evaluation. His ocular history includes bilateral radial keratotomy performed 21 years ago for moderate myopia: spherical equivalence of -4.25 D bilaterally. Postoperative uncorrected visual acuity (UCVA) wa...

We have developed a two-dimensional computer model to predict the temperature increase of the retina during femtosecond corneal laser flap cutting. Simulating a typical clinical setting for 150-kHz iFS advanced femtosecond laser (0.8- to 1-μJ laser pulse energy and 15-s procedure time at a laser wavelength of 1053 nm), the temperature increase is 0.2°C. Calculated temperature profiles show good...

AIMS Analysis of highly myopic eyes (mean myopia -11 D) with post-LASIK vitreoretinal complications (breaks, retinal detachment) that also had pre-LASIK vitreoretinal pathology (lattice, breaks). METHODS Retrospective case series. RESULTS 67 eyes in 56 patients with pre-LASIK retinal examination developed post-LASIK vitreoretinal complications. 17 of the 67 eyes (25.4%) had pre-LASIK vitreo...

PURPOSE The present study aimed to compare the postoperative contrast sensitivity functions between wavefront-guided LASIK eyes and their contralateral wavefront-guided PRK eyes. METHODS The participants were 11 healthy subjects (mean age=32.4 ± 6.2 years) who had myopic astigmatism. The spatial contrast sensitivity functions were measured before and three times after the surgery. Psycho and ...

This study aimed to investigate the effects of femtosecond laser-assisted in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) on higher-order aberrations in patients. 56 cases (112 eyes) undergoing refractive surgery in our hospital were selected in this study, all patients were randomly divided into femtosecond laser-assisted in situ keratomileusis group (LASIK gr...