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Y Urakawa

Publications and source records attributed to Y Urakawa.

8 recordsLinked to original sources
PubMed1997

CHARGE association with congenital glaucoma due to maldevelopment of the anterior chamber angle.

PURPOSE: We examined the clinicopathologic features of a male infant with the CHARGE association and bilateral congenital glaucoma. METHODS: Trabeculectomy specimens were obtained from the anterior chamber angle and examined by light and electron microscopy. RESULTS: Histopathologic examination of the trabeculectomy specimens showed immature development of the trabecular meshwork that was covered by the ciliary muscles. There were few intertrabecular spaces because the meshwork was almost completely filled with cells and extracellular substances. Deposition of a granular and/or homogeneous substance was observed in the subendothelial area of Schlemm's canal. CONCLUSIONS: Our patient exhibited features typical of the CHARGE association, but also had congenital glaucoma. We hypothesize that these clinical findings are all mediated by a neurocristopathic mechanism. Our findings suggest that the CHARGE association may predispose to anterior chamber angle maldevelopment, which can lead to congenital glaucoma.

Abnormalities, Multiple↗
PubMed1991

Extracellular materials in the endothelial meshwork of organcultured human trabecular meshwork. Morphologic and morphometric study.

Twenty-three normal cadaver eyes were used in this study. Eight trabecular meshwork explants were dissected at 45-degree intervals from a 77-year-old donor eye and cultured for 2 weeks for studying circumferential differences in the amount of extracellular materials in the endothelial meshwork. One trabecular meshwork explant was dissected from each of 22 individual eyes (age range: 64-89 years) and cultured for 2 weeks to study the effect of age on the amount of the extracellular materials. Then, 5 consecutive electron micrographs in the endothelial meshwork were obtained from the individual specimens and subjected to morphometric studies. In the endothelial meshwork, the results revealed: (1) no statistically significant circumferential differences in the amount of extracellular materials and (2) no statistically significant changes associated with aging in the amount of these materials.

Cell Count↗
PubMed1988

Human trabecular meshwork organ culture.

Human trabecular meshwork obtained from postmortem eyes was maintained in organ culture condition up to 12 weeks. The explants were dissected into specimens of three different sizes. Types 1 and 2 specimens were larger than 4 mm square and 1 mm thick, and type 3 specimens were about 1 mm3. Each specimen was placed in a depression made in the center of an agar block and the block was placed in a plastic culture dish. The space between the agar block and the culture dish was filled with liquid medium consisting of MEM Eagle supplemented with 10% fetal bovine serum, 10% chick embryo extract and 200 U/ml penicillin G. Afterwards, the explant was incubated in 5% CO2 with 100% humidity. Types 1 and 2 specimens maintained a normal appearance on electron microscopy during the entire 12 weeks of culture, while type 3 specimens showed marked cellular activation and cell loss soon after explantation. Morphometric studies regarding cell number in sections for light microscopy obtained from types 1 and 2 specimens revealed good preservation of trabecular cells during the 12 weeks of culture. Our culture system may be useful in investigating the direct effects produced on human trabecular meshwork by photocoagulation and various agents, for example anti-glaucoma drugs, steroids and viscoelastic materials.

Cadaver↗
PubMed1987

Age-related changes in the trabecular meshwork of the normal human eye.

Specimens from 17 human eyes, ranging in age from 3 to 80 years, were subjected to morphometric studies using light microscope, transmission electron microscope and scanning electron microscope, in order to clarify the age-related changes in the normal trabecular tissue. Statistical analyses showed that the cellularity in the various regions of the trabecular meshwork significantly declined with age. The spaces corresponding to the aqueous outflow pathway in each region of the meshwork also significantly decreased with age. On the other hand, extracellular materials significantly increased in amount with age in all regions of the trabecular meshwork. However, the decrease in the cellularity and the outflow pathway spaces did not show any statistically significant regional difference. These results suggest that general narrowing of the outflow pathway spaces due to the accumulation of extracellular materials with age is the cause of the increase in aqueous outflow resistance with age, and that each region of the trabecular meshwork is equally responsible for the increased resistance.

Adolescent↗