Optic nerve head neuroretinal rim blood flow differences in monkeys with laser-induced glaucoma.
BACKGROUND
The blood flow of the neuroretinal rim (NRR) of the optic nerve head (ONH) of the rhesus monkey with laser-induced glaucoma was examined.


METHODS
Argon laser photocoagulation of the trabecular meshwork to induce elevated intraocular pressure (IOP) was performed in one eye of nine normal male rhesus monkeys. The nasal and temporal NRR of the monkey ONH were examined by the Heidelberg retina tomograph/flowmeter (HRT/HRF) under neuromuscular blockade. A mixed effect analysis of variance was used to determine significant differences between eyes and between locations in the eyes.


RESULTS
The average IOP in the hypertensive glaucoma and normal eyes was 34.8 +/- 7.2 and 16.0 +/- 1.9 mmHg, respectively. The HRT determined average overall cup to disc (C/D) area ratio in the glaucoma and normal eyes, which was 0.49 +/- 0.28 and 0.22 +/- 0.16, respectively. The mean temporal NRR HRF flow in the hypertensive eyes was significantly greater than in the normotensive eyes (P < 0.0001), than in the nasal NRR of the hypertensive eyes (P < 0.0001) and than in the nasal NRR of the normotensive eyes (P < 0.01). The mean nasal NRR HRF flow in the hypertensive eyes was significantly less than in the nasal NRR of the normotensive eyes (P < 0.01). There was no statistical difference between the mean HRF flow of the temporal and nasal NRR of the normotensive eyes. The elevated IOP positively influenced the flow values in the hypertensive eye (r = 0.724).


CONCLUSIONS
The capillary microcirculation of the temporal NRR of the rhesus monkey ONH with laser-induced glaucoma has significantly increased blood flow, and the nasal NRR significantly reduced blood flow compared to blood flow in the NRR of normal normotensive monkey eyes.
Brooks
D E
DE
College of Veterinary Medicine, University of Florida, Gainesville, FL, USA. brooksd@mail.vetmed.ufl.edu
Kallberg
M E
ME
Komaromy
A M
AM
Ollivier
F J
FJ
Lambrou
G N
GN
D000818:Animals; D001783:Blood Flow Velocity / Q000662:veterinary; D005902:Glaucoma, Open-Angle / Q000503:physiopathology / Q000662:veterinary*; D007429:Intraocular Pressure; D017078:Laser-Doppler Flowmetry; D008253:Macaca mulatta; D008297:Male; D008992:Monkey Diseases / Q000503:physiopathology*; D009798:Ocular Hypertension / Q000503:physiopathology; D009898:Optic Disk / Q000098:blood supply*; D012039:Regional Blood Flow; D012171:Retinal Vessels / Q000502:physiology*