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Purpose: To examine the 5-year incidence of pseudoexfoliation (PEX) and monitor changes in related ophthalmologic variables., Design: Population-based, prospective cohort study., Methods: A random sample from the Reykjavik Population Census for persons 50 years and older was used. At baseline 1,045 participants were examined for signs of PEX including peripheral band and/or central shield of exfoliative material on the anterior lens capsule. Five years later, 846 (88.2%) of survivors returned for a follow-up visit., Results: The 5-year incidence of PEX was 3.5% in right eyes only, and 5.2% in either eye. Age increased the risk of 5-year incidence by 5% when looking at 10-year age groups (P = .02); the incidence was higher in female subjects (P = .05) than in male. A total of 27% of clinically asymmetric cases converted to clinically bilateral disease over 5 years. Intraocular pressure increased in the group that developed PEX during the 5 years, but the size of the optic cup increased most in eyes that already had PEX at baseline., Conclusion: This incidence study from Iceland confirms findings from previous prevalence studies that PEX is increasingly common with older age in this population. Earliest changes related to PEX may be subtle and difficult to detect, which may lead to some misclassification. Further study is needed to identify clinical features that can reliably detect patients at risk for developing PEX.

Purpose: To report and assess the complication of intraocular pressure (IOP) elevations after selective laser trabeculoplasty (SLT) in patients with heavily pigmented trabecular meshworks., Design: Noncomparative, observational case series., Methods: Retrospective analysis of the medical files of four glaucoma patients with heavily pigmented trabecular meshwork, who presented with IOP elevations after SLT., Results: All four glaucoma patients presented with post-SLT IOP elevations. Three had features of pigmentary dispersion syndrome, and the fourth had a heavily pigmented trabecular meshwork. Two patients had previous argon laser trabeculoplasty (ALT) in the same eye in which SLT was performed, and one had a previous ocular trauma. Eventually, three of the patients required surgical trabeculectomy., Conclusions: This case series suggests that post-SLT IOP elevations can be a serious adverse event in some glaucomatous patients. It is recommended by the authors that patients with a deeply pigmented trabecular meshwork, taking multiple topical medications and having previous ALT treatment, should be considered at higher risk for this complication.

Purpose: To evaluate the use of disk diameter as an indicator in the identification of glaucomatous optic neuropathy., Methods: We evaluated all available stereofundus photographs for 1,040 right eyes obtained in the Reykjavik Eye Study. Horizontal and vertical disk diameters were determined in a masked manner by a glaucoma specialist (K.F.D.). All disk diameters were corrected for refractive error., Results: There were significant differences (P <.05) between the corrected vertical disk diameters of normal subjects (0.189 +/- 0.018 inches) and those suspected of having glaucoma (0.202 +/- 0.020 inches) as well as between the normal and the glaucoma groups (0.206 +/- 0.029 inches). The corrected horizontal measurement showed the same pattern., Conclusions: In the Reykjavik Eye Study, optic disks meeting structural criteria for glaucoma are significantly larger than normal nerves.

Purpose: To describe the genetic basis of an autosomal dominant vitreoretinopathy in a large French-Canadian kindred., Methods: A clinical cohort study followed by laboratory-based genetic and molecular analysis. Thirty-two affected and 22 unaffected members of the kindred were examined. Candidate genes/regions for Wagner's disease and Stickler syndrome were tested for genetic linkage. Mutation analysis was carried out with direct PCR-based sequencing., Results: Funduscopic examinations of 32 affected patients revealed optically clear vitreous, vitreous veils, and radial perivascular pigmentation. Spondyloarthropathies or craniofacial abnormalities were notably absent. There was a 53% rate of retinal detachments that required surgical intervention. Genetic linkage was obtained to COL2A1, the candidate gene for Stickler's type I. A frame shift mutation in exon 2, leading to early truncation of the protein (Cys57Stop), was detected., Conclusions: Wagner's disease in this large kindred has had devastating visual consequences. In affected individuals, we found a novel COL2A1 frame shift mutation in exon 2. The mutation arises in an exon that is selectively present in vitreous collagen mRNAs, but absent in cartilage mRNAs through tissue-specific alternative splicing. Tissue-specific alternative splicing of COL2A1 mRNAs thus provides an elegant biochemical mechanism for a clinical phenotype of Wagner's disease in this kindred.

Purpose: To report the utilization of ultrasound biomicroscopy (UBM) in identifying the extension into the posterior segment of an epithelial membrane, as correlated by the histopathologic findings., Method: Case report. UBM findings before enucleation with histopathologic correlation., Results: UBM demonstrated a membrane tracking from the posterior iris surface over the ciliary body and towards the retina. Light microscopic examination disclosed the epithelial nature of this membrane., Conclusion: UBM can identify extension of an epithelial membrane into the posterior segment and thereby guide the approach to surgical management.

Purpose: To identify the mutation responsible for lattice corneal dystrophy type 1 in an extended Canadian kindred., Methods: A search for a mutation in the candidate gene, kerato-epithelin, was carried out by single-strand conformation polymorphism and sequencing analyses., Results: AC --> T mutation at position 417 was detected in exon 4 of the kerato-epithelin gene, which is expected to cause an Arg124 --> Cys change. This is the same nucleotide change described previously in two Swiss families with lattice corneal dystrophy type 1., Conclusion: Although the possibility that the three families (two previously described Swiss families and this Canadian kindred) are related has not been excluded, it appears that the unique phenotype of lattice corneal dystrophy type 1 is caused by this particular amino acid change.

Purpose: To inform ophthalmologists of the extraordinary progress in molecular genetics that is revolutionizing our understanding of ophthalmic disease and of the crucial role of the clinician in facilitating genetic discovery., Method: Review of relevant articles., Results: Genes for many mendelian-inherited eye diseases have been localized and some identified using three general approaches: positional cloning, which requires no knowledge of underlying pathophysiology; a candidate gene approach, which examines genes based on their likely function; and a positional candidate approach, which uses map location as well as candidate genes in the linked region to isolate a gene. In positional cloning, once linkage is obtained, the gene can eventually be isolated, cloned, and sequenced and mutations identified. Techniques in molecular biology and other disciplines can then be used to unravel the pathophysiology of a disease., Conclusions: Molecular genetics is advancing our understanding of the classification and pathophysiology of ophthalmic diseases. The present classification system, based largely on clinical description of disease, is being replaced with a more rational classification based on genetic causes. Future research will determine the function of known genes and identify susceptibility loci for complex diseases such as chronic open-angle glaucoma and age-related macular degeneration. More specific diagnostic, therapeutic, and preventive strategies for ophthalmic disease will be developed. Clinicians play a crucial role by inquiring about the family history of all patients, identifying individuals and families with a genetic trait, and, when appropriate, referring them for further investigation.

Purpose: To evaluate the efficacy of autologous blood injections for treating overfiltering or leaking blebs after glaucoma surgery., Method: Retrospective review of ten eyes of ten patients who received intrableb autologous blood injections for hypotonous maculopathy., Results: After intrableb blood injection, average intraocular pressure increased from 4.3 mm Hg to 6.4 mm Hg, and average visual acuity improved from 20/88 to 20/77. These results, however, were not statistically significant., Conclusion: Our results with autologous blood injection are less favorable than those of previous reports, although further study with a larger case series is needed.