Title :
Retinal capillary velocities with elevated intraocular pressure
Author :
Glucksberg, M.R. ; Jensen, P.S.
Author_Institution :
Dept. of Biomed. Eng., Northwestern Univ., Evanston, IL, USA
Abstract :
We examined the effect of increased intraocular pressure on the distribution of erythrocyte velocities within capillaries of the cat retina. Retinal capillary networks of 4 cats were observed using gradient index of refraction (GRIN) lens endoscopy near the optic disk and compared to similar measurements in the periphery within the nasal sector of the retina while intraocular pressure (IOP) was varied. Erythrocyte velocity and density were determined using time-based correlation algorithms from 15 second video segments. We determined that retinal capillary flow was insensitive to changes in intraocular pressure for pressures below 30 mmHg retinal blood and stasis was never observed. Above 30 mmHg retinal blood velocity was diminished and the incidence of stasis increased with increasing intraocular pressure
Keywords :
biomechanics; blood flow measurement; blood vessels; cell motility; eye; cat retina; erythrocyte density; erythrocyte velocities; gradient index of refraction lens endoscopy; intraocular pressure; nasal sector; optic disk; periphery; retinal blood velocity; retinal capillary flow; retinal capillary networks; retinal capillary velocities; stasis; time-based correlation algorithms; video segments; Animals; Blood flow; Blood pressure; Endoscopes; Eyes; Probes; Retina; Xenon;
Conference_Titel :
[Engineering in Medicine and Biology, 1999. 21st Annual Conference and the 1999 Annual Fall Meetring of the Biomedical Engineering Society] BMES/EMBS Conference, 1999. Proceedings of the First Joint
Conference_Location :
Atlanta, GA
Print_ISBN :
0-7803-5674-8
DOI :
10.1109/IEMBS.1999.804482
