No abstract

SUMMARY Fluorescein iris angiography and fluorophotometry were performed on a series of 9 patients with bilateral and 11 with unilateral pseudoexfoliation, 12 bilateral aphakes with pseudoexfoliation, and 7 unilateral aphakes with bilateral pseudoexfoliation. Angiography showed a loss of radial iris vessels, a heavy leak of fluorescein from the pupil margin, progressive neovascularisation of the outer 2/3 of the iris, and less constantly a network of fine new vessels in the inner '/3 of the iris stroma. These changes were absent in unaffected eyes. After cataract extraction there seemed to be a definite lessening of fluorescein leak from the pupil margin. Fluorophotometry showed a much higher fluorescein concentration at the anterior focus in eyes with pseudoexfoliation than in normal controls or in fellow unaffected eyes. There was a much smaller rise in fluorescein concentration at the posterior focus in a minority of affected eyes. The ranges of fluorescein concentrations at the anterior focus in both phakic and aphakic patients with bilateral pseudoexfoliation did not differ significantly. The concentration at the anterior focus of unilateral aphakes with bilateral pseudoexfoliation was lower than in the fellow phakic eye. These findings suggest that the neovascular reaction seen in pseudoexfoliation is associated with patchy occlusion of the normal iris vasculature, occurs in the anterior segment of the eye, and does not continue to progress after removal of the lens.It is still not clear how the condition of pseudoexfoliation (PXF) of the lens capsule develops. The material appears to be an amyloid-like substance with fibrils embedded in a ground substance, which appears at a variety of ocular and extraocular sites.'" The vascular changes described by Vannas"2 13 are very marked, and their relationship to the pseudoexfoliative process is of particular interest.Accordingly we have re-examined these vascular changes and also measured the leakage of fluorescein in a group of patients in order to determine whether there is any evidence of (1) vascular changes or increased fluorescein leakage occurring in the clinically unaffected fellow eye in patients with unilateral PXF; (2) increased fluorescein leakage in the posterior segment of affected eyes, with heavy leakage in the anterior segment; (3) change in the pattern of the vascular reaction and in the fluorescein leakage following cataract extraction in affected eyes.

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Topical beta-blockers reduce the intraocular pressure (IOP) by blockade of sympathetic nerve endings in the ciliary epithelium causing a fall in aqueous humour production. Two types of topical beta-blockers are available for use in glaucoma: nonselective, which block both beta 1- and beta 2-adrenoceptors; and cardioselective, which block only beta 1-receptors. Of the beta-Blockers commercially available, timolol, levobunolol, metipranolol and carteolol are nonselective, and betaxolol is cardioselective. Twice-daily timolol is probably the most effective agent in lowering IOP, although levobunolol is equally effective and can be used once daily with little difference in effect. Carteolol is used twice daily and any theoretical advantage in diminished side effects conferred by its partial beta-agonist activity compared with timolol has not been fully substantiated. Metipranolol is effective twice daily and does not have partial beta-agonist activity. Betaxolol has an effect comparable to timolol in lowering IOP, but is less effective in some patients. beta-Blockers can be used with other antiglaucoma medications, but their combined action with epinephrine (adrenaline) is suspect, particularly in the case of the nonselective beta-blockers, and the effect should be assessed in patients on an individual basis. Local stinging can be a problem in some patients with betaxolol. The most serious side effects of beta-blockers are the exacerbation of chronic obstructive airways disease with nonselective agents and the precipitation of bronchospasm in some patients. Betaxolol seems relatively free of adverse respiratory effects, although this may be dose-related and extreme caution should still be exercised in patients with any history of respiratory illness. Because of the lower risk of precipitating side effects, betaxolol is probably the beta-blocker of first choice for use in glaucoma; timolol or levobunolol are reserved for patients who do not respond satisfactorily to betaxolol and are quite free of respiratory disease.

The diagnosis of congenital fibrosis of the extraocular muscles (CFEOM) encompasses several different inherited strabismus syndromes characterized by congenital restrictive ophthalmoplegia affecting extraocular muscles innervated by the oculomotor and/or trochlear nerves. The OMIM database (http://www.ncbi.nlm.nih.gov/Omim/) currently contains four familial CFEOM phenotypes: CFEOM1-3, which map to the FEOM1-3 loci (MIM 135600, 602078, 604361), respectively, and congenital fibrosis of the vertically acting extraocular muscles (MIM 600638), reported in a single family without a corresponding genotype. We have had the opportunity to study the reported family with this fourth phenotype and now demonstrate that their phenotype can be reclassified as CFEOM3 and that it maps to FEOM3, flanked by D16S498 to 16qter, with a maximum lod score of 6.0.