purpose: to measure corneal power using different methods to assess agreement between these methods among patients who underwent photorefractive keratotomy. methods: in this prospective comparative study, keratometry was measured in 66 eyes of 33 refractive surgery candidates using manual keratometry (kr), conventional topography average central corneal power (accp), galilei total corneal power...

MyOPiC LASer COrreCtiOn The most popular type of laser correction for myopia is LASIK. Myopic laser correction is achieved by central corneal ablation, which reduces the refractive power of the anterior corneal surface. Myopic LASIK has been shown to be effective in correcting low to moderate myopia.1,2 LASIK correction of high myopia has been fraught with quality issues until recently. Factors...

PURPOSE To evaluate with the use of corneal topographic data the differences between total corneal power calculated using ray tracing (TCP) and the Gaussian formula (GEP) in normal eyes, eyes that previously underwent laser in situ keratomileusis/photorefractive keratectomy (LASIK/PRK), and theoretical models. METHODS TCP and GEP using mean instantaneous curvature were calculated over the cen...

Diabetic keratopathy is an ocular complication that occurs with diabetes. In the present study, the effect of diabetic keratopathy on corneal optical density, central corneal thickness, and corneal endothelial cell count was investigated. One hundred and eighty diabetic patients (360 eyes) were enrolled in the study during the period from March, 2012 to March, 2013. The patients were divided in...

The purpose of this study was to investigate the agreement between the clinical history method (CHM), Orbscan IIz, and Pentacam in estimating corneal power after myopic excimer laser surgery. Fifty five patients who had myopic LASIK/PRK were recruited into this study. One eye of each patient was randomly selected by a computer-generated process. At 6 months after surgery, postoperative corneal ...

We have developed a new optical procedure to determine the optimum power of intraocular lenses (IOLs) for cataract surgery. The procedure is based on personalized eye models, where biometric data of anterior corneal shape and eye axial length are used. A polychromatic exact ray-tracing through the surfaces defining the eye model is performed for each possible IOL power and the area under the ra...

We present a comparison of corneal biometric values from dense volumetric spectral domain optical coherence tomography (SDOCT) scans to reference values in both phantoms and clinical subjects. We also present a new optically based "keratometric equivalent power" formula for SDOCT that eliminates previously described discrepancies between corneal power form SDOCT and existing clinical modalities...

purpose: to determine the long-term visual outcomes and complications of penetrating keratoplasty (pk) performed for keratoconus. methods: hospital records of patients with keratoconus who underwent pk at the ophthalmology center of shaheed sadoughi, yazd, iran, during 1992-2003 were reviewed. we studied records of 84 pk procedures in 72 keratoconus patients. data including best corrected visua...

OBJECTIVE To evaluate the effects of the intrastromal corneal ring, a device developed to reduce myopia, on corneal asphericity in a large set of eye bank eyes. METHODS Forty-one deturgesced eye bank eyes were implanted with intrastromal corneal rings of five different thicknesses, ranging from 0.25 mm to 0.45 mm. Corneal asphericity, before and after implantation, was examined using two diff...