We present an optical scheme to actively suppress statistical noise in Laser Speckle Imaging (LSI). This is achieved by illuminating the object surface through a diffuser. Slow rotation of the diffuser leads to statistically independent surface speckles on time scales that can be selected by the rotation speed. Active suppression of statistical noise is achieved by accumulating data over time. ...

determinants of early onset haze were retrospectively explored in patients who had been undergone laser-assisted sub-epithelial keratectomy (lasek) in a private eye clinic. the technique included creating an epithelial flap following 20 seconds exposure to 20% alcohol. ‘optimized’ ablation profile was used by allegretto laser (wavelight technologie). following repositioning of the flap, a singl...

UNLABELLED This report documents the effects of photorefractive keratectomy (PRK) in an astronaut during a 12-day Russian Soyuz mission to the International Space Station in 2008. Changing environmental conditions of launch, microgravity exposure, and reentry create an extremely dynamic ocular environment. Although many normal eyes have repeatedly been subject to such stresses, the effect on an...

PURPOSE The corneal change induced by refractive procedures influence both the postoperative refractive status and the ocular spherical aberration (SA). We evaluated changes in corneal SA after three types of surface ablation: phototherapeutic keratectomy (PTK), myopic photorefractive keratectomy (PRK), and myopic wavefront-guided laser epithelial keratomileusis (LASEK). METHODS Twenty-six ey...

Purpose. To assess refractive and visual outcomes and patient satisfaction of wavefront-guided photorefractive keratectomy (PRK) in eyes with myopia and compound myopic astigmatism, with the ablation profile derived from a new Hartmann-Shack aberrometer. Methods. In this retrospective study, 662 eyes that underwent wavefront-guided PRK with a treatment profile derived from a new generation Hart...

To the Editor: We thank Drs. Talamo and Abad and Mr. Lim (Refractive Regression after Excimer Laser Photorefractive Keratectomy. J Refract Surg 1996;12:757[letter]) for their comments and are gratified that their findings support our hypothesis that the refractive regression after photorefractive keratectomy (PRK) is not a result of the thicker regrowth of connnective tissue or epithelium in th...

BACKGROUND We report the case of an 81-year-old woman with a history of radial keratotomy 9 years prior who developed endophthalmitis without preceding keratitis 4 days after uneventful photorefractive keratectomy surgery. This case report utilized clinical examination and microbacterial laboratory findings. FINDINGS Diagnosis of bacterial endophthalmitis was made via clinical examination and...

PURPOSE To assess the effects of topical corticosteroids (fluoromethalone) following photorefractive keratectomy (PRK). METHODS Both eyes of 654 patients had PRK with a minimum of 4 months between treatments. Topical corticosteroids were prescribed for one eye only. Endpoints were assessed by comparing the ratio of intended to actual refractive change in the corticosteroid treated eye with th...

PURPOSE The safety and efficacy of corneal collagen cross-linking (CXL) and topography-guided photorefractive keratectomy (PRK) using a different sequence and timing were evaluated in consecutive keratoconus cases. METHODS This study included a total of 325 eyes with keratoconus. Eyes were divided into two groups. The first group (n=127 eyes) underwent CXL with subsequent topography-guided PR...

PURPOSE To compare the corneal power measurements obtained using different topographic instruments after myopic photorefractive keratectomy (PRK). METHODS Patients with myopia who were candidates for corneal refractive surgery were sequentially included. Pre-PRK and six months post-PRK corneal powers were measured using Javal manual keratometer, Orbscan II, Galilei, Tomey TMS4, and EyeSys 200...