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Biomedical subjects

O Atsumi

Publications and source records attributed to O Atsumi.

2 recordsLinked to original sources
PubMed1993

[Ultrastructural study on retinal arteriolar caliber irregularity in stroke-prone spontaneously hypertensive rats].

Ultrastructural changes in the arteriolar wall with caliber irregularity of spindle type, rosary type and diffuse dilatation type were studied in stroke-prone spontaneously hypertensive rats (SHRSP) aged 4, 6 and 10 months with systolic blood pressures of 210-240 mmHg by use of intravenously injected gelatin fluorescein preparation (IVGFP) and light and electron microscopy. Tridimensional graphic models were reconstructed from light micrographs of cross-sectioned serial preparations using a computerized micrograph-analyser. In the spindle type, I found markedly thickened media and smooth muscle cell necrosis at the narrowed portion of the arteriole central to the ampullar portion and a marked stretch and disappearance of the inner elastic lamina at the ampullar portion. These vascular changes of arteriolosclerosis were most advanced in the spindle type among three types of caliber irregularity. Tridimensional graphic models disclosed that there was no correlation between the wall thickening and luminal diameter of the arteriole. These results may explain the process of development of caliber irregularity in SHRSP.

Animals↗
PubMed1991

[A case of presumed radiation optic neuropathy].

A case of a 37-year-old woman with radiation optic neuropathy was reported. She had undergone subtotal removal of the right orbital tumor (adenoid cystic carcinoma) by frontal craniotomy, followed by radiation therapy (64Gy). She had been quite well until she noticed a gradual loss of vision in her right eye 18 months later. Her visual acuity was 0.2 in the right eye and 1.5 in the left eye with right relative afferent pupillary defect and dense central scotoma. Funduscopy revealed optic disc swelling with surrounding retinal edema and small hemorrhage in the right eye. Fluorescein angiography revealed a hypoperfusion area and obstruction of the small retinal vessels in the posterior pole, but this was not large enough to explain the dense central scotoma. Although prednisolone therapy gave temporary improvement, the visual function gradually deteriorated.

Adult↗