Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “RETINAL VESSELS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 793 records · Page 44Linked to original sources
PubMed2006

Cardiovascular risk factors and retinal microvascular signs in an adult Japanese population: the Funagata Study.

OBJECTIVE: To describe the prevalence of retinal vascular signs and their association with cardiovascular risk factors in a Japanese population. DESIGN: Population-based cross-sectional study. PARTICIPANTS: Adult persons aged 35 years or older from Funagata, Yamagata Prefecture, Japan (n = 1481). METHODS: The Funagata Study is a Japanese population-based study of persons aged 35 years or older, and included 1961 nondiabetic participants (53.3% of 3676 eligible subjects). A nonmydriatic retinal photograph was taken of 1 eye to assess retinal microvascular signs. Retinal arteriolar wall signs (focal arteriolar narrowing, arteriovenous nicking, enhanced arteriolar wall reflex) and retinopathy were assessed in 1481 participants without diabetes (40.3% of eligible persons) using a standardized protocol. Using a computer-assisted method, retinal vessel diameters were measured in 921 participants with gradable retinal image (25.1% of eligible persons). MAIN OUTCOME MEASURES: Prevalence of retinal microvascular signs and their association with cardiovascular risk factors. RESULTS: Moderate or severe focal arteriolar narrowing, arteriovenous nicking, enhanced arteriolar wall reflex, and retinopathy were found in 8.3%, 15.2%, 18.7%, and 9.0%, respectively, of the study population. Mean (+/-standard error) values for retinal arteriolar diameter were 178.6+/-21.0 mum, and mean values (+/-standard error) for venular diameter were 214.9+/-20.6 mum. Older persons were more likely to have retinal arteriolar wall signs, retinopathy, and narrower retinal vessel diameters. After adjusting for multiple factors, each 10-mmHg increase in mean arterial blood pressure was associated with a 20% to 40% increased likelihood of retinal arteriolar signs and a 2.8-mum reduction in arteriolar diameter. Retinopathy was associated with higher body mass index and both impaired glucose tolerance and impaired fasting glucose. CONCLUSIONS: In nondiabetic Japanese adults, retinal arteriolar wall signs were associated with older age and increased blood pressure, whereas retinopathy was associated with older age, higher body mass index, impaired glucose tolerance, and impaired fasting glucose. These findings are comparable with data from white populations.

Adult↗
PubMed1997

Visualization and flow of platelets and leukocytes in vivo in rat retinal and choroidal vessels.

PURPOSE: To directly visualize the flow of leukocytes in choroidal vessels and the flow of platelets in retinal vessels in a rat without incision by fluorescein leukocyte angiography (FLA) using a scanning laser ophthalmoscope (SLO). METHODS: Blood was withdrawn from a tail vein of a Sprague-Dawley rat with a tuberculin syringe traced with sodium heparin and mixed with sodium fluorescein. The fluorescent plasma layer was diluted with saline solution, centrifuged and then the overlying plasma discarded. The remaining cell suspension was diluted with saline to create the original hematocrit, then infused into the vein of the same rat while performing fluorescein angiography with an SLO. The angiographic image was recorded on a videotape using time-lapsed photography. RESULTS: Fluorescent platelets were detected and the flow within the retinal vessels traced over time. Fluorescent leukocytes in the choroidal vessels were also detected and the flow of a leukocyte was traced and its relative velocities were plotted against the time sequence. The relative size and fluorescence intensities of the platelets and leukocytes in the angiographic image corresponded well with the smear of the blood preparation. CONCLUSIONS: FLA using an SLO can be used to detect the flow of platelets in the retinal vessels and the flow of leukocytes in the choroidal vessels in the experimental rat eye model.

Animals↗
PubMed1995

Diabeteslike proliferative retinal changes in galactose-fed dogs.

OBJECTIVE: To determine whether diabeteslike lesions associated with the proliferative stage of diabetic retinopathy develop in galactose-fed dogs, since studies designed to define the complex biochemical effects of prolonged hyperglycemia on retinal vessels have been hampered by the lack of an animal model that mirrors both the early and advanced stages of diabetic retinopathy. METHODS: Eyes from 9-month-old male beagles fed a daily diet containing either 30% nonnutrient filler (control diet) or 30% galactose (galactose diet) for up to 84 months were enucleated and histologically examined. RESULTS: Retinal vessel changes associated with the proliferative stage were observed in two of nine galactose-fed dogs while the remainder demonstrated retinal changes that included the appearance of microaneurysms, acellular capillary beds associated with areas of nonperfusion, and intraretinal microvascular abnormalities. Proliferative changes were evidenced by the formation of preretinal fibrous membranes and the appearance of fibrovascular membranes on the retinal surface and on the posterior hyaloid membrane. No retinal lesions were observed in similar dogs fed a control diet for up to 84 months. CONCLUSION: The galactose-fed dog appears to be the first animal model that can develop diabeteslike retinal vessel changes associated with both the early and advanced stages of retinopathy, including the proliferative stage.

Animals↗
PubMed1992

RPE transplants stabilize retinal vasculature and prevent neovascularization in the RCS rat.

Previous reports indicate that in the Royal College of Surgeons (RCS) rat a decline in the retinal vessel density accompanies the loss of the normal architecture of the deep bed. This begins at about three months with neovascularization that originates in the deep vessel bed and develops in the direction of the retinal pigment epithelial (RPE) cells by four months. A surgical technique has been developed recently for the transplantation of healthy RPE cells into the subretinal space of the RCS rat, resulting in the rescue of photoreceptor cells. This permits evaluation of the possibility that such transplants also protect the retinal vessels. We report for the first time: (1) the stabilization of the normal retinal vasculature by maintenance of the density and architecture of the deep vessel bed; and (2) prevention of neovascularization of the RPE by the surgical transplantation of healthy RPE cells into the subretinal space of the RCS rat. More specifically, we show a maintenance of the deep vessel bed density under the transplant in contrast to a significant reduction in the vessel density that had taken place in corresponding areas in nongrafted and sham injected controls at four months of age. The vessel density in the transplanted group is statistically different from the nongrafted and the sham injected groups. We also report a significant decline in the number of neovascularization profiles around the transplant site of the RPE-grafted RCS retina. We also note that the pathological changes in the vasculature of the RCS rat occur in a predictable central to peripheral gradient.

Animals↗
PubMed1989

[Detection of retinal vascular endothelial damage by fluorescein isothiocyanate-labelled platelet].

Fluorescein isothiocyanate (FITC)-labelled platelets were prepared in Sprague Dawley rats, and brought back into the rat through their femoral veins. Their ability to detect the photocoagulation-induced damage in the occluded retinal vessels was examined by epifluorescence microscopy in whole mount retinal specimens and cryostat specimens. The photocoagulation effects on the major retinal vessels by yellow dye (577 nm) and orange red (600 nm) laser, with parameters of 100 mu, 0.05 sec, 70 m W and 3 exposures were compared. The occluded vessels showed extensive accumulation of labelled platelets in the specimens. The portions photocoagulated by the yellow laser also showed accumulation, but not those by the orange red laser. This difference was considered to be due to the difference of hemoglobin absorption at each wavelength.

Animals↗