Measurement of retinal blood velocity and flow rate in primates using a liposome-dye system.
A recently developed liposome-dye method was used to make quantitative measurements of blood velocity and volumetric flow rates in the retina of the rhesus monkey. After systemic injection of a liposome-encapsulated fluorescent dye (calcein), the release of a bolus of the dye in the retina was triggered by an ophthalmic argon laser. Initially, calcein was entrapped at a high concentration and the fluorescence of the dye in the lipid vesicle was quenched. After laser exposure, the liposomes released a bolus of dye at the laser exposure site in a specific vessel of the retina. The released dye formed a well-defined, fluorescent wavefront in the exposed artery or vein. By measuring the distance the dye traveled in the vein over a set time interval, it was possible to measure blood velocity in retinal vessels of various diameters, and to calculate volumetric flow rates in those vessels.
Khoobehi
B
B
Louisiana State University Medical Center School of Medicine, New Orleans 70112.
Peyman
G A
GA
Niesman
M R
MR
Oncel
M
M
D000818:Animals; D001783:Blood Flow Velocity; D004337:Drug Carriers; D005452:Fluoresceins / Q000008:administration & dosage*; D005456:Fluorescent Dyes / Q000493:pharmacokinetics; D005654:Fundus Oculi; D007267:Injections; D007834:Lasers; D008081:Liposomes; D008253:Macaca mulatta; D012160:Retina / Q000098:blood supply*; D013997:Time Factors
D004337:Drug Carriers; D005452:Fluoresceins; D005456:Fluorescent Dyes; D008081:Liposomes; C007740:fluorexon