1/12. Recurrent macular corneal dystrophy type II 49 years after penetrating keratoplasty.recurrence of macular corneal dystrophy after keratoplasty is rare. We report light microscopic, immunohistochemical, electron microscopic, and serologic findings in a 78-year-old woman who underwent regrafting 49 years following the first penetrating keratoplasty. Examination of the corneal button revealed deposits of glycosaminoglycans in the graft beneath the Bowman layer, throughout the stroma, and in the endothelium with positive staining for antigenic keratan sulfate. By transmission electron microscopy, intracellular and extracellular deposits of a fibrillogranular material were detected in the stroma, descemet membrane, and endothelium. The serum level of antigenic keratan sulfate was normal. Our findings indicate that macular corneal dystrophy type II may show late recurrence after penetrating keratoplasty with intense deposition of antigenic keratan sulfate in all corneal layers.- - - - - - - - - - ranking = 1keywords = transmission (Clic here for more details about this article) |
2/12. Lattice corneal dystrophy associated with the Ala546Asp and Pro551Gln missense changes in the TGFBI gene.PURPOSE: To report a phenotypic variant of lattice corneal dystrophy associated with two missense changes, Ala546Asp and Pro551Gln, in the transforming growth factor-beta-induced gene (TGFBI). DESIGN: Experimental study. methods: Genomic dna was obtained from the proband as well as affected and unaffected family members. exons 4, 11, 12, and 14 of the TGFBI gene were amplified and sequenced. Additionally, a corneal button excised from the proband was examined by light and transmission electron microscopy. Haplotype analysis was performed on the proband's family and members of a previously identified pedigree with the same TGFBI gene missense changes. RESULTS: Bilateral, symmetric, radially arranged, branching refractile lines within and surrounding an area of central anterior stromal haze were noted in the proband. Multiple polymorphic, refractile deposits were noted in the mid and posterior stroma in both the proband and her daughter. light and electron microscopic analyses demonstrated amyloid and excluded the presence of deposits characteristic of granular corneal dystrophy. Screening of TGFBI exon 12 in the proband and her affected daughter revealed two missense changes, Ala546Asp and Pro551Gln (both absent in 250 control chromosomes). Haplotype analysis suggested that the mutations in this family and in a previously identified pedigree reflect a founder effect, rather than an independent occurrence. CONCLUSIONS: We present a phenotypic variant of lattice corneal dystrophy associated with the Ala546Asp and Pro551Gln missense changes in exon 12 of the TGFBI gene. A common ancestor appears to account for the missense mutations observed in this pedigree and in a previously reported family.- - - - - - - - - - ranking = 1keywords = transmission (Clic here for more details about this article) |
3/12. Identification of oxytalan fibers in Salzmann's nodular degeneration.PURPOSE: diagnosis of Salzmann's nodular degeneration is based on clinical findings, as histopathologic findings in nodules are nonspecific on routine examination. This study demonstrates that presence of oxytalan fibers (ie, elastic system fibers) in lesions of Salzmann's nodular degeneration under light and electron microscopy allows definitive diagnosis. methods: A 55-year-old woman noticed white nodular lesions on both corneas. Excised lesion tissues were examined under light microscopy with special staining and transmission electron microscopy. RESULTS: Nodular lesions comprised hyalinized connective tissue showing nonspecific findings on routine histologic examination. However, oxidized aldehyde fuchsin staining yielded positive results in lesions, indicating the presence of oxytalan fibers. Transmission electron microscopy identified bundles of microfibrils in lesions, confirming the presence of oxytalan fibers. CONCLUSIONS: light microscopic examination by oxidized aldehyde fuchsin staining should be performed when diagnosing Salzmann's nodular degeneration.- - - - - - - - - - ranking = 1keywords = transmission (Clic here for more details about this article) |
4/12. Granular corneal dystrophy Groenouw type I. A report of a probable homozygous patient.A case of severe granular corneal dystrophy is described. The patient, who is most probably homozygous for the dominantly inherited dystrophy gene, is the product of a first cousin marriage with both parents mildly affected by the same dystrophy. The case report describes an early onset and a severe course with two grafts in each eye before the age of 17. Pictures of the clinical appearance, histology and transmission electronmicroscopy are shown.- - - - - - - - - - ranking = 1keywords = transmission (Clic here for more details about this article) |
5/12. Anterior mesenchymal dysgenesis of the eye. Congenital hereditary endothelial dystrophy and congenital glaucoma.The present report describes a patient with congenital glaucoma and iris hypoplasia who underwent repeated surgery to control the glaucoma. Despite these procedures, the patient's corneas opacified progressively, and bilateral penetrating keratoplasties were performed. Histopathological studies, including transmission and scanning electro microscopy of the corneal buttons, demonstrated specific changes of Descemet's membrane and the endothelium typical of congenital hereditary endothelial dystrophy (CHED). CHED has usually been considered to be a specific clinical entity that is not combined with congenital glaucoma or other significant abnormalities of the anterior segment of the eye. The present case indicates that these conditions may be combined, which is of importance when dealing with infants with congenital glaucoma and corneal opacities.- - - - - - - - - - ranking = 1keywords = transmission (Clic here for more details about this article) |
6/12. iridocorneal endothelial syndrome with contralateral guttate endothelial dystrophy. A light and electron microscopic study.Both eyes from a 75-year-old woman who had unilateral closed-angle glaucoma, characteristic endothelial specular microscopic findings, and slowly progressive tractional iris abnormalities consistent with essential iris atrophy were obtained postmortem and studied by light, scanning, and transmission electron microscopy. Clinically, the nonglaucomatous right eye had an open-angle, normal iris, and severe endothelial dystrophy with three-plus corneal guttae. In this eye, results of histopathologic examination disclosed marked endothelial degeneration and typical guttate excrescences on Descemet's membrane. In contrast, the endothelium in the fellow eye with the essential iris atrophy variant of the iridocorneal endothelial (ice) syndrome was strikingly different. The endothelial cells were relatively well preserved and exhibited marked pleomorphism, anisocytosis, and flat, occasionally paired oval nuclei. Binucleate cells also were observed. The endothelial monolayer had secreted a new layer of fibrillar extracellular matrix material on the posterior surface of Descemet's membrane. extracellular matrix material was found interposed between the iris and cornea in zones of synechial closure, and an endothelial membrane was present on the anterior surface of the iris. These observations support the hypothesis that the iris abnormalities in essential iris atrophy are secondary to endothelial proliferation. The endothelial cells displayed neither tonofilaments nor abundant apical microvilli. The latter observation suggests that increased numbers of endothelial microvilli are not responsible for the characteristic specular microscopic picture seen in the ice syndrome.- - - - - - - - - - ranking = 1keywords = transmission (Clic here for more details about this article) |
7/12. Endothelial and epithelial-like cell formations in a case of posterior polymorphous dystrophy.histology of the endothelial and epithelial-like cells, vesicles, and membranes seen on the posterior corneal surface in posterior polymorphous dystrophy were examined by light microscopy and scanning and transmission electron microscopy in a 3-month-old female infant. The entire posterior surface of both corneas was covered by a geographic pattern of endothelial and epithelial-like cells, sometimes creating vesicles and sometimes creating partially detached sheets of cells. The thickness of Descemet's membrane varied widely, showing a tendency to be most complete under the remaining endothelial cells and thinner or absent under the epithelial-like cells. Details of this histology have important implications for our understanding of congenital diseases of corneal endothelium.- - - - - - - - - - ranking = 1keywords = transmission (Clic here for more details about this article) |
8/12. A new variety of spondyloepiphyseal dysplasia characterized by punctate corneal dystrophy and abnormal dermal collagen fibrils.Several individuals from one family are described with a unique form of spondyloepiphyseal dysplasia. Characteristic features include short-trunked short stature, punctate corneal dystrophy and marked disorganization of dermal collagen fibrils when examined by transmission electron microscopy. Inheritance is compatible with either dominance and a variable expression or X-linkage. Although the basic defect has not been determined, the tissue distribution is consistent with a defect in a non-collagenous component that affects collagen fibril formation or stability.- - - - - - - - - - ranking = 1keywords = transmission (Clic here for more details about this article) |
9/12. Transmission and scanning electron microscopic studies on endothelial cells in macular corneal dystrophy.Macular corneal dystrophy of both eyes in a 50-year-old man was studied by light microscopy and transmission and scanning electron microscopies. The endothelial cells contained empty vacuoles and numerous granules stained with alcian blue and periodic acid fuchsin. The endothelial cells were thin, especially at the guttata excrescences of the Descemet's membrane. Transmission electron microscopy revealed two types of vacuoles in the endothelium. The first type, which has been reported before, contained fine fibrillar material. The second type, described for the first time in this paper, was larger in size than the first type, and contained mostly amorphous material which appeared at the same electron density as the empty space of the anterior chamber, while a small amount of fibro-membranous materials were occasionally seen in the vacuoles. The second type of vacuoles sometimes appeared to be flattened. Cytoplasmic organelles of the endothelial cells and endothelial junctions were normal. endothelial cells at the guttata excrescences were thin and contained only fine filaments. Slight depressions were observed on the endothelial surface facing the anterior chamber. Scanning electron microscopy of the endothelium showed an irregular surface which was composed of craters, nodules and pits. The cytoplasmic membrane of the endothelial cells at the top of the craters were continuous with that at the bottom of the craters. Marginal folds of the endothelial cells were obscure. vacuoles of the first type were identical to those seen in the keratocytes of this disease. The second type of vacuoles and the guttata excrescences of the Descemet's membrane were thought to represent the craters and nodules on the endothelial surface.- - - - - - - - - - ranking = 1keywords = transmission (Clic here for more details about this article) |
10/12. Electron microscopic study of recurrent Reis-Bucklers' corneal dystrophy.We studied the cornea of a 51-year-old woman with recurrent Reis-Bucklers' dystrophy with the transmission electron microscope. The patient had had a superficial keratectomy nine years earlier. The epithelium removed in a second keratectomy contained distended endoplasmic reticulum and swollen mitochondria. The basal layer showed some cells in mitosis and a slight increase in the number of dark cells. The anterior portion of the removed stroma contained dense collagen fibrils, with the appearance of curly fibrils, which is characteristic of this disease. There were also severe degenerative changes in the stroma. These changes in the collagen fibers and alterations in keratocytes of the deeper layers were less severe than those of the superficial layer. A biopsy of the bulbar conjunctiva showed reduplication of the basement membrane.- - - - - - - - - - ranking = 1keywords = transmission (Clic here for more details about this article) |
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