Ohkuma H
Kansai Medical University
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Ophthalmology | 2000
Masanobu Uyama; Kanji Takahashi; Jun Kozaki; Nobuko Tagami; Takada Y; Ohkuma H; Hiroshi Matsunaga; Takashi Kimoto; Tetsuya Nishimura
PURPOSE To clarify clinical features and pathophysiology and to evaluate surgical outcome of subscleral sclerectomy for primary uveal effusion syndrome. DESIGN Prospective, consecutive noncomparative case series. PARTICIPANTS Nineteen eyes of 16 patients diagnosed with uveal effusion syndrome treated in our clinic between 1989 and 1998. METHODS Patients were examined by routine ophthalmologic examinations, fluorescein and indocyanine green angiography; measurement of the axial length of the eyeball; magnetic resonance imaging; and echography. Subscleral sclerectomy (sclerectomy under the scleral flap) was performed at the equator on all patients. Histologic examination of excised sclera was carried out on all samples. Patients were followed for outcome over time. MAIN OUTCOME MEASURES Reattachment of the choroid and retina with resolution of the serous fluid. RESULTS Three subgroups were identified: In type 1, nanophthalmic eye; the eyeball is small (average axial length 16 mm) and high hypermetropic (average +16 diopters); in type 2, the eyeball size is normal (average axial length 21 mm) with small refractive error; and in type 3, the eyeball size is normal. Histologically, types 1 and 2 demonstrated abnormal sclera with disorganization of collagen fiber bundles and deposits of proteoglycans in the matrix, whereas type 3 showed normal sclera. Subscleral sclerectomy was effective for types 1 and 2, inducing postoperative resolution of the subretinal fluid. However, type 3 eyes were not helped by this technique. CONCLUSIONS Primary uveal effusion syndrome is caused by abnormalities of the sclera and increased resistance to transscleral fluid outflow as subscleral sclerectomy is an effective treatment in types 1 and 2 only, correct preoperative classification is essential for early surgical management.
Clinical Pediatrics | 1987
Hirohiko Higashino; Tsuguo Horii; Yoshiaki Ohkusa; Ohkuma H; Chiyonori Ino; Midori Nakazawa; Haruaki Izumi; Yohnosuke Kobayashi
A 7-year-old girl had dry mouth and recurrent infections of the lacrimal fistulae with decreased lacrimal secretion. All four puncta were absent, and a Schirmer test showed decreased lacrimal secretion. Salivary gland imaging with sodium pertechnetate 99mTcO4 showed absence of all major salivary glands. Lower lip biopsy disclosed normal structure of the salivary gland. No evidence of abnormal inheritance patterns could be demonstrated.
Graefes Archive for Clinical and Experimental Ophthalmology | 1998
Hidemi Maeda; Nahoko Ogata; Xianjin Yi; Masamitsu Takeuchi; Ohkuma H; Masanobu Uyama
Abstract • Background: The intravitreal injection of ornithine produces selective damage to the retinal pigment epithelium (RPE) and results in a loss of RPE, choriocapillaris and photoreceptor cells. To elucidate the mechanism of secondary retinal atrophy, we investigated the presence of apoptotic cells in a rat model of ornithine-induced retinopathy. • Methods: At 6 and 12 h and 1, 2, 4, 7, 14 and 28 days after an intravitreal injection of L-ornithine hydrochloride in rat eyes, we removed the eyes and subjected them to histopathological examination. We detected apoptotic cells by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate digoxigenin nick end labeling (TUNEL) assay, which stains the 3′-OH ends of fragmented DNA. We used electron microscopy to detect the apoptotic cells morphologically. • Results: RPE cells were selectively damaged immediately after ornithine administration. TUNEL-positive photoreceptor cells appeared exclusively in the photoreceptor cell layer 12 h after ornithine administration. The number of TUNEL-positive cells increased throughout the 2 days following the injection, then decreased markedly. TUNEL-positive cells remained until 28 days, when the photoreceptor cells had disappeared. The ganglion cell layer, inner nuclear layer and damaged RPE cells were negative for TUNEL staining during all stages. The electron microscopic study also revealed the pyknotic nuclei of apoptotic photoreceptor cells. • Conclusion: An intravitreal injection of ornithine caused primary damage to the RPE, and subsequently some of the photoreceptor cells revealed apoptosis by TUNEL assay. These findings suggest the dysfunction of the RPE causes photoreceptor cell death according to the intrinsic program of an apoptotic mechanism.
Japanese Journal of Ophthalmology | 1997
Ichiro Fukushima; Kanae Kusaka; Kanji Takahashi; Kishimoto N; Tetsuya Nishimura; Ohkuma H; Masanobu Uyama
We compared indocyanine green (ICG) and fluorescein angiography for evaluation of choroidal neovascularization (CNV). Cast preparations of CNV induced in monkey eyes by laser photocoagulation were correlated with ICG and fluorescein angiographies of the same CNV formations. Fluorescein angiography was more effective, in general, than ICG angiography in detecting CNV; however, CNVs with subretinal hemorrhage (2 of 35 sites) were visible only with ICG angiography. In early phase ICG angiography, CNV formations that casts showed to be dense or composed of thick vessels were seen, but less dense areas were not visible. Lesions that ICG angiography revealed as leaking were not differentiated morphologically from non-leaking areas by the CNV casts. This study confirms that only ICG angiography can identify CNV hidden by subretinal hemorrhage, although fluorescein angiography is otherwise superior. Indocyanine green angiography is indicated as a valuable complement to fluorescein angiography for evaluation of CNV.
Archive | 1987
Masanobu Uyama; Ohkuma H; Itagaki T; Kazuya Yamagishi; Tetsuya Nishimura; Kanji Takahashi
Senile disciform macular degeneration is increasing as a cause of blindness in elderly aged people. It is well known senile disciform macular degeneration is caused by development of choroidal neovascularization.
Japanese Journal of Ophthalmology | 1997
Hiroshi Matsunaga; Akira Ando; Takashi Matsubara; Fukushima I; Takahashi K; Ohkuma H; Uyama M
We performed an experimental study on choroidal circulatory disturbance to clarify basic problems about interpretation of retino-choroidal lesions in indocyanine green fluorescence angiography (ICG angiography). We severed the posterior ciliary arteries to produce choroidal circulatory disturbance. Fluorescein angiography and ICG angiography were performed at one week, and one month after occlusion. These findings were compared with histopathological findings. One week after occlusion, the area of choroidal infarct showed occlusion of choriocapillaris and proliferation of the retinal pigment epithelial (RPE) cells, this area showed hypofluorescence in the early phase ICG angiography. The hypofluorescence area increased in the late phase. One month after occlusion, the lesion showed loss of choriocapillaris at the center and proliferation of fibroblast-like cells at the edge of the lesion. The subretinal strand showed hyperfluorescence in late phase ICG angiography. Proliferated RPE cells masked ICG fluorescence in the late phase. Fibroblast-like cells showed tissue staining. When reading ICG angiography, we have to take into account that the ICG angiogram is greatly modified by condition of the RPE.
Japanese Journal of Ophthalmology | 1997
Hidemi Maeda; Masamitsu Takeuchi; Kanji Takahashi; Itagaki T; Ohkuma H; Masanobu Uyama
An intravitreal injection of a small amount of 1-ornithine hydrochloride damages the retinal pigment epithelium (RPE) selectively in monkey eyes. In this paper, we examined the rat eye and observed similar results. Clinically, retinal edema appeared immediately after injection and showed hyperfluorescence on a fluorescein angiograph after 3 days. Histopathologically, RPE showed marked swelling 3 hours after injection, then became necrotic and disappeared gradually. One month after injection, retinal structure was maintained in the area where RPE regenerated to cover Bruchs membrane, but in the area where RPE cells disappeared, the photoreceptor cells and choriocapillaris degenerated and finally disappeared. In the eyes injected intravitreally with NaCl solution of equivalent osmosis microvacuoles were seen but no necrotic change in RPE. Thus, a small amount of ornithine damaged RPE selectively, and induced disappearance of the photoreceptors and choriocapillaris secondarily.
Archive | 1998
Hidemi Maeda; Nahoko Ogata; Xianjin Yi; Masamitsu Takeuchi; Ohkuma H; Masanobu Uyama
The retinal pigment epithelium (RPE) has a major role in maintaining the homeostasis and visual activity of the retina. Various pharmacological agents are known to affect the pigment epithelial cells primarily1,2 or to affect the neurosensory retina and damage the RPE secondarily3–5. When the physiological functions of the pigment epithelium are altered the overlying retina is also affected, resulting in a decrease of visual function.
Japanese Journal of Ophthalmology | 1997
Hidemi Maeda; Masamitsu Takeuchi; Kanji Takahashi; Itagaki T; Ohkuma H; Masanobu Uyama
We observed the process of disappearance of the choriocapillaris after loss of the retinal pigment epithelium (RPE) induced by intravitreal injection or ornithine. Three hours after administration of ornithine, the RPE cells swelled remarkably in the posterior pole, but, the endothelial cells of the choriocapillaris remained intact. At 3 days, the RPE cells became necrotic, but the choriocapillaris still preserved its in normal appearance. At 7 days, RPE disappeared completely in the posterior pole and the choriocapillaris displayed evidence of atrophy; the swollen lumen of the choriocapillaris became narrow the cytoplasm of the endothelium was swollen, and the number of fenestrae was reduced. On the other hand, these changes were not seen where the RPE remained. At 14 days, in the posterior pole, the lumen of the choriocapillaris occluded by the swollen endothelial cells. At 28 days, the choriocapillaris completely disappeared and the large choroidal vessel was directly in contact with Bruchs membrane. These results showed that the RPE is correlated with the presence of the choriocapillaris.
Japanese Journal of Ophthalmology | 1984
Miki K; Ohkuma H; Stephen J. Ryan