Contributions of the superoxide dismutase 1 and zinc finger protein 469 (ZNF469) genes to keratoconus.

Keratoconus (KC) is a multifactorial, progressive, degenerative corneal disorder with an incidence of approximately 1 in 2,000 subjects.

Contributions of VSX1 gene to keratoconus.

Keratoconus (KC) is a complex, genetically heterogeneous, multifactorial degenerative corneal disorder, with incidence of approximately 1 per 2000 of the population. KC follows an autosomal recessive or dominant pattern of inheritance and is, apparently, associated with genes which interact with environmental, genetic and/or other factors. The present report focuses on the VSX1 gene, for which there is general agreement that it is involved in KC and other corneal pathologies, and critically details the evidence for its involvement in KC.

Descemet's stripping endothelial automated keratoplasty using Tan EndoGlide endothelium insertion system.

PURPOSE: The purpose of this study was to evaluate early visual and refractive outcomes of Descemet's stripping endothelial keratoplasty (DSAEK). METHOD: Nine eyes of 7 male and 2 female patients, mean age 73 years, were treated with DSAEK. Eight had pseudophakic bullous keratopathy and 1 had advanced Fuch's syndrome. Patients were followed up for a mean of 11.4 months (range, 4-26). The DSAEK technique consisted of stripping Descemet's membrane and endothelium from a recipient cornea and transplanting the posterior stroma and endothelium of a donor cornea using the Tan EndoGlide. The mean operating time was 61.89 minutes (standard deviation [SD], 9.3). RESULTS: The median donor diameter was 8.375 mm (range, 8.25-8.75) and the mean donor thickness was 114.4 µm (range, 98-129). Mean preoperative sphere was -2.41 that changed postoperatively in -1.21. Mean endothelial cell loss was 25% (range, 23%-45%) at 6 months after surgery. Corneal pachymetry was reduced from 796.6 µm preoperatively to 535.5 µm postoperatively. Best corrected vicual acuity (BCVA) was 20/40 or better postoperatively and exceeded the preoperative BCVA in all eyes. No graft failure was present. Two partial graft dislocations (1st and 5th postoperative day) were observed. One graft was successfully attached after reinjecting an air bubble (rebubbling) in the anterior chamber and the other graft was reattached with 4 10/0 nylon sutures after failed rebubbling. CONCLUSIONS: The key to successful endothelial transplantation is the protection and preservation of as many donor endothelial cells as possible. The TAN EndoGlide is a device that consistently delivers a donor lenticule through a small incision with minimal endothelial loss, while making the insertion procedure relatively reliable and consistent, with the surgeon in full control of the donor at all stages of insertion. The endothelial cell loss during this technique is comparable (if not better) with other endothelial graft insertions systems.

Iris configuration in accommodation in pigment dispersion syndrome.

PURPOSE: This study was conducted in order to investigate the effect of accommodation on the iris morphology and iridolenticular contact, in eyes with Pigment Dispersion Syndrome and Pigmentary Glaucoma, using high-resolution ultrasound. METHODS: We performed a prospective observational study, examining a group of 30 Pigment Dispersion Syndrome and Pigmentary Glaucoma patients (49 eyes) and a smaller group of eight 'normals' non-Pigment Dispersion Syndrome patients (8 eyes). All patients underwent ultrasound biomicroscopy, before and during accommodation. RESULTS: The iris profile before accommodation was found convex in 48.5%, flat in 19.7% and concave in 31.8%. Following accommodation the iris configuration remained unchanged in 66.2%, increased in concavity in 20.3% and decreased in concavity in 13.5%. CONCLUSIONS: The effect of accommodation on iris configuration and accommodation is highly variable. From our experience the measurement of iris configuration using ultrasound biomicroscopy may not be a useful method of evaluating the effect of different treatments on iris configuration.

Intraobserver and interobserver reliability of the R/D score for evaluation of iris configuration by ultrasound biomicroscopy, in patients with pigment dispersion syndrome.

UNLABELLED: The work has been presented at The Association for Research in Vision and Ophthalmology (ARVO) Annual Meeting, Fort Lauterdale, Florida, May 1999. PURPOSE: To evaluate inter- and intraobserver variability of the R/D score in assessing the iris configuration in Pigment Dispersion Syndrome patients. METHODS: Fifty-seven high-resolution ultrasound biomicroscopy images were obtained by a single ophthalmologist. All images were examined twice by each of three ophthalmologists, the second assessment being at least 2 weeks after the first. Each observer was masked to their colleagues' and their previous measurements. R/D scores were calculated at each examination. Agreement between and amongst observers was assessed using Bland-Altman plots. In addition, the R/D scores were categorised and reassessed using the Kappa statistic. RESULTS: Intraobserver variability was small, the average differences between first and second scores of each observer being less than 0.01 units. Agreement within observers was 89% or higher, with Kappa values of 0.8 or higher, indicating almost perfect agreement. Interobserver variability was, however, greater. Although there was substantial agreement between two of the observers (87% agreement, first assessment; 80%, second assessment with respective kappa statistics of 0.78 and 0.66), they only moderately agreed with the other observer (kappa statistics between 0.55 and 0.68). CONCLUSIONS: This study suggests that when using R/D scores to demonstrate changes in iris configuration, assessments should preferably be made by the same observer.