[Autoregulation in ischemia of the optic nerve in the human].
BACKGROUND
Autoregulation is defined as the maintenance of constant blood flow in a vascular system in spite of changes in perfusion pressure (PPm).


METHODS
PPm was decreased by increasing the intraocular pressure (IOP) with a suction cup and optic nerve blood flow was measured with the laser Doppler flowmetry technique (LDF) in 9 normal volunteers.


RESULTS
The blood flow was autoregulated down to a PPm of 13 mm Hg (IOP = 47 mm Hg).


CONCLUSIONS
These results confirm previous studies in cats and monkeys. The mechanism of autoregulation is probably a decrease in resistance due to capillary recruitment.
Titzé
P
P
Institut de Recherches en Ophtalmologie, Sion.
Hero
M
M
Petrig
B L
BL
Cranstoun
S D
SD
Riva
C E
CE
D000328:Adult; D002200:Capillary Resistance / Q000502:physiology*; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D007511:Ischemia / Q000503:physiopathology*; D017078:Laser-Doppler Flowmetry; D008297:Male; D008875:Middle Aged; D009900:Optic Nerve / Q000098:blood supply*; D012016:Reference Values