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The ocular findings in eight patients with Cockayne syndrome included enophthalmos, hyperopia, poor pupillary dilation, and retinal dystrophy in all patients. Four patients had strabismus. Two patients had cataracts. Three patients had nystagmus. Visual acuity was relatively well preserved in six patients, including a 25-year-old man with a visual acuity of 20/60 in each eye despite advanced retinal pigmentary changes. Failure of DNA and RNA synthesis to recover after ultraviolet light exposure as well as selective loss of repair of transcriptionally active DNA may account for the ocular abnormality in this progeric syndrome.

The eyes of a 22-month-old girl with the cobalamin C complementation type of combined methylmalonic aciduria and homocystinuria were studied with light and electron microscopy. We observed vacuolization of the iris pigment epithelium, loss of photoreceptors in the central 3.3 mm of the macula, partial loss of the nerve fiber and ganglion cell layers between the fovea and optic disk, and partial optic atrophy. The sclera in the posterior pole was thickened with deposition of mucopolysaccharide. Electron microscopy showed inclusions containing fine granular material in conjunctival fibrocytes; corneal epithelium, keratocytes, and endothelial cells; iris pigment epithelium; ganglion cells; retinal pigment epithelium; and choroid and scleral fibrocytes. Enlarged mitochondria and clear vacuoles distended the corneal endothelial cells. We found evidence of possible lysosomal dysfunction and mucopolysaccharide storage, as well as a clinicopathologic correlation of the macular degeneration in this disease.

One hundred sixty consecutive patients with the Marfan syndrome were reviewed for ocular, cardiovascular, and skeletal abnormalities, and were graded by severity. The most striking ocular abnormality was enlargement of the globe, presumably caused by scleral stretching. Staphylomata were not a feature of any of the patients seen, nor was keratoconus. The cornea, in fact, was flattened but not thinned. Among the 160 patients, 193 eyes showed dislocation of the lens. Dislocation of the lens was positively correlated with increased ocular axial length and with decreasing KJ readings. We postulate that the ocular pathologic changes are primarily caused by stretching of the tunica scleralis, and that the zonular fibers (thus under stress may "give" or may rupture in their area of presumably least density which may be the area of developmental fusion of the optic vesicle. In a small proportion of cases the lens dislocation was progressive. There was no correlation between ocular findings, on one hand, and the skeletal and cardiovascular abnormalities on the other. However, there was a good degree of intrafamilial consistency with regard to absence or presence of ocular pathology. The absence of correlation between the ocular and systemic findings in our data on these 160 patients is best explained by the existence of more than 1 point mutation, which may give rise to different but clinically similar phenotypes. The results of our calculations of mutation rate were compatible with such an explanation.

A 33-year-old man, 28 years after enucleation for a perforating injury, had a four-year history of slowly progressive proptosis of his prosthesis. Examination revealed a spherical mass filling the space normally occupied by the globe. A cyst lined by conjunctival epithelium was encountered on surgical exploration.

Ectopia lentis was first described more than 200 years ago, but its value as a significant diagnostic clue to the presence of other ocular and systemic disorders has only recently been appreciated. Ectopia lentis may cause a marked reduction in visual acuity, which varies with the type and degree of dislocation and the presence of other ocular abnormalities. An approach to the diagnostic evaluation of the patient with ectopia lentis is outlined. The differential diagnosis is reviewed in detail both clinically and histologically. The complications of ectopia lentis and the appropriate management of affected patients are discussed.

A case of mucopolysaccharidosis, Type II-A (Hunter syndrome, severe) is described, with emphasis on ocular ultrastructural findings. Single membrane-bound structures containing fibrillogranular and, less commonly, multi-membranous material were found in conjunctival epithelium, pericytes and fibrocytes; corneal epithelium, keratocytes, and endothelium; trabecular endothelium; iris pigmented epithelium, smooth muscle, and fibrocytes; ciliary pigmented and nonpigmented epithelium and fibrocytes; retinal pigment epithelium and ganglion cells; optic nerve astrocytes and pericytes; and sclerocytes. The most striking accumulation was in the nonpigmented ciliary epithelium. These findings are compared with those seen in MPS II-B, and in other systemic mucopolysaccharidoses. The nature and distribution of inclusions are not specific to any one disorder, but help to signal the presence of one of the storage disorders. Distension of corneal keratocytes may play a role in the corneal clouding seen in some of these disorders. The importance of tissue examination, especially conjunctival biopsy, in the diagnosis of storage disorders and in assessment of future modes of therapy for the mucopolysaccharidoses is discussed.

The ophthalmologic findings in 15 patients with childhood adrenoleukodystrophy (ALD) are reviewed. In this X-linked demyelinating disease with adrenal dysfunction, relentlessly progressive visual loss followed by optic atrophy occurs months to years after the diagnosis is established based on neurologic symptoms and biochemical abnormalities. Visual loss is mainly due to central nervous system (CNS) demyelination involving the visual tracts, but primary retinal ganglion cell degeneration may also be operative. All patients in this study were male. Vision ranged from 20/20 to no light perception (NLP). All but one patient with bilateral cataracts had normal anterior segment examinations. Seven patients had exotropia, and esotropia developed in one patient. Electroretinography (ERG) and electrooculography (EOG) findings were normal in two patients with severe visual loss. Macular pigmentary changes were observed in three patients. Optic pallor was noticed in seven patients. Optic nerve hypoplasia was seen in one patient. Visual-evoked responses were abnormal in two patients and borderline in one. Progressive visual field abnormalities were noticed in three patients, large field cuts in two patients, and normal fields in another two patients. The diagnosis of ALD should be considered in all boys presenting with unexplained visual loss, dementia, and adrenal dysfunction.

The first linkage of disease traits on the human X-chromosome was reported in 1937, and the first assignment of a human disease to an autosome was made 26 years later in 1963. Now, after only 19 years, there are at least 338 assignments to loci on the human chromosome map. This amazing expansion of information extends to eye diseases. In this review, basic mechanisms of mutation are discussed, and the basic methodologies used for gene assignments are explained. All of the eye-related, definite, autosomal assignments are presented. The diseases that have regional assignments on the X-chromosome are discussed, and the remaining X-linked eye diseases are listed in table form.