Sequential Intrastromal Corneal Ring Implantation and Cataract Surgery in a Severe Keratoconus Patient with Cataract

A 49-year-old man with an uncorrected visual acuity (UCVA) of 20 / 1000, a best spectacle-corrected visual acuity (BSCVA) of 20 / 400, keratometric readings of K1 = 59.88 x 82degrees / K2 = 45.88 x 172degrees, and an inferior steepening that was consistent with keratoconus in his left eye was treated with clear-cornea phacoemulsification and an intraocular lens (IOL) implantation after insertion of keraring intrastromal corneal ring segments for severe keratoconus and cataract. An asymmetrical pair of kerarings was implanted with the assistance of a femtosecond laser in September 2008; the one segment was 250 microm and the other was 150 microm and both were placed at 70degrees. Three months after the kerarings were implanted, clear-cornea phacoemulsification and IOL implantation were performed on the left eye. After surgery, both the UCVA and the BSCVA of the left eye improved by eight lines. Postoperative central keratometry showed a decrease of 7.35 diopters in the left eye. Both the postoperative refraction (-0.75 -0.75 x 60degrees) and the keratometric reading (K1 = 50.05 x 93degrees / K2 = 48.83 x 3degrees) remained stable one month following the procedures. Thus, the sequential order of intrastromal corneal rings implantation and cataract surgery can be considered as a treatment option in patients with severe keratoconus and cataract.

Reproducibility of Morphoscopic Contrast Sensitivity Obtained with the Visual Capacity Analyzer in Glaucoma Patients

PURPOSE: To determine the reproducibility of morphoscopic contrast sensitivity test values in the patients with primary open angle glaucoma using the Visual Capacity Analyzer (ACV) designed for assessing full visual performance including contrast sensitivity. METHODS: Morphoscopic contrast sensitivity was measured in each five glaucomatous eyes. The measurement was repeated 5 times under two different luminance level of screen (maximum and 3 cd/m2). RESULTS: Under maximum luminance background, the coefficients of variation (CV) and the reliability coefficients (RC) for the spatial frequencies examined in this study ranged from 2.1% to 29.3%, from 92.1% to 100.0%, respectively. Under 3cd/m2 luminance level of screen, the CV ranged from 2.7% to 32.0%, and the RC ranged from 90.7% to 99.9%. CONCLUSIONS: The results indicates that for the spatial frequencies examined, the morphoscopic contrast sensitivity test using ACV shows good reproducibility in glaucomatous patients.

The Effect of Larger and Blend Zone Ablation on Optical Aberrations in Laser Epithelial Keratomileusis (LASEK)

PURPOSE: The purpose of this study is to investigate the postoperative high order aberration after LASEK and to evaluate the effects of LASEK on high order aberration using larger and blend zone ablation. METHODS: Twenty patients out of 28 patients who received treatment were followed up for 3 months. In each case, one eye received conventional ablation LASEK and the other eye received larger and blend zone ablation LASEK. Preoperative and postoperative RMS (root mean square) of Bille aberration maps measurements were made with WaveScan Wavefront(TM) system (VISX, Santa Clara, U.S.A.). RESULTS: RMS of Bille aberration maps at post operation 1 month and post operation 3 months displayed a statistically significant increase compared with preoperative value. (p<0.05) In post operation 3 month, larger and blend zone ablation LASEK treated eyes displayed a statistically significant lower post operative RMS compared to those of conventional ablation LASEK.(p<0.05) CONCLUSIONS: High order aberrations at post operation 1 month and post operation 3 months increased compared with preoperative value. High order aberration after LASEK with larger and blend zone ablation are less pronounced compared to those associated with conventional ablation LASEK. By using larger and blend zone ablation it is possible to minimize the high order aberration of the eye and improve visual results for patients undergoing LASEK.