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Objective: To present evidence for a type IV collagen alpha5 chain (alpha5[IV]) abnormality in the anterior lens capsule of a patient with anterior lenticonus associated with Alport syndrome., Methods: The anterior lens capsule obtained from a 54-year-old man with anterior lenticonus associated with Alport syndrome was examined ultrastructurally and stained immunohistochemically for the alpha chains of type IV collagen, alpha1(IV) to alpha6(IV). A search was also made for a mutation in the COL4A5 complementary DNA encoding the alpha5(IV) chain by reverse transcription-polymerase chain reaction of illegitimate transcripts., Results: The anterior lens capsule of the patient was much thinner than that of normal subjects and lacked the alpha3(IV) to alpha6(IV) chains immunohistochemically, while control specimens stained positively for all of the alpha(IV) chains. The patient had a C-to-T transition at nucleotide 5231 causing a nonsense mutation, R1677X, in the COL4A5 complementary DNA., Conclusion: Our findings demonstrated that normal anterior lens capsules express all of the alpha(IV) chains and that a patient with anterior lenticonus associated with Alport syndrome had a mutation in the COL4A5 gene resulting in the lack of immunoreactivity to alpha3(IV) to alpha6(IV) chains in the anterior lens capsule. Clinical Relevance This study showed abnormal composition of alpha(IV) chains in the anterior lens capsule of a patient with anterior lenticonus caused by a nonsense mutation in the COL4A5 gene. Further investigation of the phenotype-genotype relationship will provide a better understanding of the molecular pathogenesis of anterior lenticonus.

True exfoliation or lamellar delamination of the lens capsule is a rare disorder in which the lens capsule is thickened and the superficial portion of the lens capsule splits from the deeper layer and extends into the anterior chamber. The pathogenesis of this disorder is not clear, but intense infrared radiation has been thought to be the main causative factor. We describe a patient with a history of heat exposure who had a cataract and was found to have bilateral delamination of the anterior lens capsule. Findings from light microscopy and scanning and transmission electron microscopy demonstrated a lamellar separation of the anterior portion of the lens capsule, confirming the diagnosis of true exfoliation.

We describe a patient with Chandler's syndrome variant of the iridocorneal endothelial syndrome in whom ectopic Descemet's membrane was found intraoperatively on the anterior surface of the lens. Initially, the membrane was confused with the anterior lens capsule during extracapsular cataract extraction, leading to the performance of a pseudocapsulorrhexis. Electron microscopy disclosed that the epilenticular membrane was composed of multiple layers of abnormal basement membrane consistent with the iridocorneal endothelial syndrome.

Calcific phacolysis has been previously described histopathologically in the enucleated eyes of three patients with unilateral posttraumatic total blindness. Each eye showed dissolution of a mature cataractous lens with dispersion of calcific lens material throughout the globe. We studied a patient in whom the signs of calcific phacolysis developed 19 months following intraoperative dislocation of a cataract into the vitreous. Partial removal of calcific particles was achieved by subtotal vitrectomy and lensectomy, with subsequent penetrating keratoplasty. Corneal histopathological findings showed a deposition of calcified lens particles between Descemet's membrane and retrocorneal fibrous membrane. Despite diffuse retinal calcification, the patient's visual acuity was 20/400. To our knowledge, this is the first report of calcific phacolysis occurring after surgical dislocation of a cataract into the vitreous and wherein treatment resulted in some preservation of vision. Early diagnosis and aggressive therapy may improve the visual prognosis in this condition.

A 70-yr-old woman underwent anterior segment reconstruction with repeated penetrating keratoplasty for visual rehabilitation. On removal of the failed keratoplasty button, the posterior chamber intraocular lens was found to be encased in a dense fibrous membrane that almost totally obliterated the anterior and posterior chambers of the eye. Anterior segment reconstruction included excision of the fibrous membrane, removal of the intraocular lens, iridoplasty, gonioplasty, anterior vitrectomy, and repeated penetrating keratoplasty. Recognition of fibrous tissue that extended through each of the four positioning holes of the optic of the lens implant and its transection was essential in avoiding complications during removal of the intraocular lens. Histopathologic and ultrastructural examination of the excised membrane revealed areas of metaplastic lens epithelium and fibrous scar tissue. This study, using immunofluorescence, is the first, to our knowledge, to characterize the specific collagenous components of a peripseudophakic membrane.

This report describes a patient with true exfoliation of the lens capsule. Recurrent anterior uveitis eventually necessitated lens extraction from the left eye. Scanning and transmission electron microscopy demonstrated areas of capsular dehiscence and evidence of in vivo cellular degeneration. A comparison of true and pseudoexfoliation of the lens capsule is made and the term "capsular delamination" is proposed for the case reported.

Previous observations suggest that "pseudoexfoliation of the lens capsule" may be a disease in which cells produce abnormal basement membrane material. Electron microscopic studies indicate that exfoliative material can be produced by cells throughout the anterior segment of the eye. This report describes abundant exfoliative material on the ciliary and iridic epithelia but not on the surface of the lens whose epithelial cells were completely necrotic. Exfoliative material also was observed in the anterior iridic stroma close to a newly formed abnormal endothelial basement membrane, suggesting that exfoliative material may be produced locally within the iris. Furthermore, typical exfoliative material, best considered a filamentous, banded basement membrane with 500-A periodicity, in the wall of a short posterior ciliary artery in the orbit indicates that the exfoliative process is not solely limited to ocular tissues. The term "basement membrane exfoliation syndrome" is proposed for this entity.

We present the ocular manifestations in a series of 37 hemizygous male and 25 heterozygous female patients with Fabry's disease. The ocular findings typically do not impair vision, but are unique and diagnostic. Whorl-like corneal deposits were seen in almost all patients and were more severe in the heterozygotes. The lens showed cream-colored anterior capsular deposits, sometimes in striking "propeller" distribution, in one third of the hemizygotes, and in none of the heterozygotes. A faint but unique posterior capsular opacity with a branching radial pattern was seen in 37% of the hemizygotes and 14% of the heterozygotes. Conjunctival vessel aneurysmal dilations and retinal vessel tortuosity were both more frequent and severe in the hemizygotes. Severe visual loss occurred in two hemizygotes as a result of unilateral total central artery occlusions.

Pathological examination of a girl with congenital syphilis revealed a focal granulomatous reaction involving the anterior uvea and lens. Krajian's (silver) stain exhibited spiral forms that were morphologically compatible with Treponema pallidum within the lens cortex. These findings have been rarely reported in early congenital lues.