Biomedical subjects

Kanji Takahashi

Publications and source records attributed to Kanji Takahashi.

21 records · Page 2Linked to original sources

PubMed2002

[Clinical dose finding study of indocyanine green to detect choroidal neovascularization in patients with exudative age-related macular degeneration].

PURPOSE: To evaluate the proper clinical dosage of indocyanine green(ICG) in angiography for detecting choroidal neovascularization(CNV) of exudative age-related macular degeneration(AMD). SUBJECTS AND METHODS: Indocyanine green angiography (IA) was performed using a randomized crossover method with two different doses on two occasions. Ease of detection, side effects and clinical serum data were also evaluated. RESULTS: Among the 39 eyes, detection of CNV using 12.5 mg and 25 mg was most effective in 21 and 31 eyes respectively, showing a statistically significant difference. Slight vomiting was observed temporarily in one patient who had taken 25 mg. CONCLUSION: A dose of 25 mg is appropriate for detection of CNV of exudative AMD and this dosage raises no safety concerns.

Aged↗

PubMedDate not supplied

Quantitative evaluation of ischemia-reperfusion injury by optical coherence tomography in the rat retina.

PURPOSE: To determine whether optical coherence tomography (OCT) can detect early retinal changes after ischemia-reperfusion injury in rats. METHODS: The intraocular pressure (IOP) was elevated to induce retinal ischemia in brown Norway rats. After 90 min of ischemia, the IOP was reduced, and after reperfusion of 1, 2, 4, or 7 days, OCT was performed. After the OCT examination, the eyes were enucleated and histological sections were made. RESULTS: The OCT-determined mean retinal thickness was 168 +/- 16.9 microm in the untreated control group, and 177 +/- 2.16, 170 +/- 7.55, 159 +/- 5.34, and 140 +/- 5.56 microm on days 1, 2, 4, and 7, respectively, in the ischemia-reperfusion group. The histologically determined retinal thicknesses correlated with those obtained by tomographic images, but the histologic thicknesses were 9.5% to 18.5% thinner than those obtained by OCT. Fixation and dehydration of the histological specimens most likely caused tissue shrinkage. CONCLUSIONS: OCT can detect retinal changes quantitatively after ischemia-reperfusion injury, and the retinal thicknesses obtained from OCT images are probably a better measure of the true retinal thickness than those measured on histological sections.

Animals↗

PubMedDate not supplied

Effects of local administration of interferon-beta on proliferation of retinal pigment epithelium in rabbit after laser photocoagulation.

PURPOSE: To investigate whether local administration of interferon (IFN)-beta promotes proliferation of the retinal pigment epithelium (RPE) in vivo. METHODS: Following local injection of IFN-beta into the sub-Tenon space of rabbit eyes, the penetration of IFN-beta into various intraocular areas was determined by means of enzyme-linked immuno-adsorbent assay. Retinal lesions were produced by laser photocoagulation (PC), and IFN-beta (1 x 10(6) IU, 1 x 10(5) IU, or 1 x 10(4) IU) was administered into the sub-Tenon space. Physiological saline was substituted for IFN-beta in controls. The proliferation of RPE cells was inspected histopathologically. RESULTS: After IFN-beta administration, IFN-beta was found in all intraocular areas examined, with the highest concentration detected in the choroid. After PC, profuse proliferation of RPE cells began earlier in the rabbits that received the highest dose of IFN-beta than in the control rabbits; repair of the central part of the coagulated lesion in those rabbits was complete within 7 days after PC. In control rabbits, the histopathologic wound repair process proceeded more slowly and to a limited extent. Proliferation of RPE cells in the low and medium dose IFN-beta-treated rabbits was similar to that in the control rabbits. CONCLUSION: The present study demonstrates that repair of the PC-induced retinal lesions, particularly the proliferation of RPE cells, is promoted in vivo by local administration of IFN-beta.

Administration, Topical↗