W. R. Green

Neuronal ceroid lipofuscinosis: Ocular histopathologic and electron microscopic studies in the late infantile, juvenile, and adult forms

Diagnosis of the neuronal ceroid lipofuscinoses (NCLF), a group of recessively inherited neurolipidoses, must rely on clinical as well as light and electron microscopic histopathologic findings, as a precise biochemical defect has not yet been identified. We have studied the eyes from two patients with the late infantile and juvenile forms of the disease. On electron microscopy, we observed, almost exclusively, inclusions with curvilinear profiles in the late infantile type, while multimembranous and curvilinear bodies were seen in juvenile NCLF. In both forms of the disease, retinal destruction seems to start at the photoreceptor and outer retinal levels and progresses from the macular area to the periphery. Conjunctival biopsy is helpful in the diagnosis of these disorders, as demonstrated in the adult case presented here.

A HISTOPATHOLOGIC STUDY OF THE PIGMENTED FUNDUS LESIONS IN FAMILIAL ADENOMATOUS POLYPOSIS

A postmortem examination of the eyes of a 61-year-old woman with familial adenomatous polyposis was performed using light microscopy and transmission and scanning electron microscopy. Numerous lesions of the retinal pigment epithelium (RPE) were identified, which had one of three basic configurations: a monolayer of hypertrophic cells, a mound of RPE cells interposed between the RPE basement membrane and the inner collagenous layer of Bruchs membrane, or a multilayered mound of hyperplastic cells. The presence of abnormal pigment granules in cells within the lesions and cells from areas of grossly normal RPE indicates a generalized defect in melanogenesis. Although the pigmented fundus lesions of familial adenomatous polyposis are often referred to clinically as congenital hypertrophy of the RPE, the prominent component of cellular hyperplasia more appropriately designates them as hamartomas of the RPE. Their development is likely the result of the same loss of regulatory control of cell growth and replication that gives rise to the multiple colorectal polyps and soft tissue tumors that characterize this condition.

Histopathologic and electron-microscopic features of corneal and scleral collagen fibers in osteogenesis imperfecta type III

Abstract• Background: This report describes the histopathologic and electron-microscopie features of an eye from a patient with osteogenesis imperfecta type III. In particular, the diameters of corneal stromal and scleral collagen fibers were determined. • Methods: The eyes of an 18-year-old white male with osteogenesis imperfecta type III were examined by light arid electron microscopy arid the pathological features were compared with an age-matched control eye. • Results: The cornea was clear. The sclera had a blue color and was moderately thinned, especially at the equator. Light microscopy revealed absence of Bowmans layer. Transmission electron microscopy confirmed complete absence of Bowmans layer without evidence of scarring or inflammation. The collagen fibers of the corneal stromal lamellae were about 25% narrower than in the control, but the cornea was otherwise unremarkable ultrastructurally. The collagen fibers of the sclera were approximately 50% narrower than in the control and were much more uniform in size. Prominent portions of clastic fibers, which are usually only present in a small number in the inner portion of the sclera, were prescrit throughout the sclera. • Conclusion: We propose that it is the uniformity of the scleral collagen fibers which gives the sclera translucence, producing the blue color often observed clinically in osteogenesis imperfecta. Absence of Bowmans layer of the cornea did not interfere with the stability of the cornea in this case. This appears to be the first published pathological examination of the eye in ostcogenesis imperfecta type III.

Nutritional amblyopia: A histopathologic study with retrospective clinical correlation

During a 10-year period ending in 1985, we observed atrophy of the maculopapillary bundle in both eyes of 25 cases examined post mortem. We retrospectively examined the clinical history and general autopsy findings for evidence of malnutrition. An adequate clinical history was obtained in 24 patients, and an autopsy was performed on 21 patients. Our review disclosed that all 25 patients had marked nutritional deprivation, most commonly from alcohol abuse (20 patients), advanced carcinoma (8 patients, 7 of whom were also alcohol abusers), and other malnutritional and disabling conditions (4 patients). A history of heavy smoking was documented in 11 patients. Our findings support the contention that dietary deficiency plays a role in the pathogenesis of the condition that in the past has been referred to as tobacco-alcohol amblyopia and more recently has been called nutritional amblyopia.

Terrien's marginal degeneration: Clinicopathologic case reports

We report the clinicopathologic features of seven cases of Terriens marginal degeneration. Three specimens studied were lamellar resections and four were full-thickness corneal segments. Of the four full-thickness specimens, three were semilunar and one was an annular (“doughnut-shaped”) specimen. All cases had stromal thinning, vascularization, lipid keratopathy and local absence of Bowmans membrane. Descemets membrane was markedly thickened and the endothelium was intact. Three of the four full-thickness corneal specimens showed healed ruptures of Descemets membrane. One specimen had four healed successive ruptures in Descemets membrane in the same area. The corneal endothelium in that area had produced a basement membrane that totalled 35 μm in thickness. The clinical and histopathologic features of pellucid and Terriens marginal degeneration are similar. When idiopathic peripheral corneal thinning remains clear, it is regarded as pellucid degeneration; vascularization, scarring, and lipid keratopathy are regarded as Terriens marginal degeneration. Breaks in Descemets membrane contribute to these latter changes.