Movaffaghy A, Riva C E, Petrig B L
Institut de Recherche en Ophtalmolgie, Sion.
Klin Monbl Augenheilkd. 1998 May;212(5):350-2. doi: 10.1055/s-2008-1034903.
Autoregulation of optic nerve head blood flow (Fonh) in response to decreases in perfusion pressure has been demonstrated in animals and humans. The aim of this study was to determine change in Fonh when systemic blood pressure is increased.
Blood flow parameters, i.e. relative mean velocity, number, and flux of red blood cells in the ONH tissue (Velonh, Volonh and Fonh, respectively) were measured by laser Doppler flowmetry in one eye of 13 normal subjects (aged 16 to 58 years), at baseline, during, and after isometric exercises consisting of squatting. Brachial artery blood pressure was measured by sphygmomanometry. IOP was measured at baseline and at the end of squatting.
During squatting mean arterial pressure increased from 103 +/- 6 mm Hg to 139 +/- 58 mm Hg (average +/- 95% confidence interval), IOP increased from 13 +/- 0.5 to 17 +/- 1 mm Hg. An average increase in PPm from 56 +/- 4 to 80 +/- 7 mm Hg induced no significant (p > 0.05) change in the blood flow parameters. The sensitivity (detection threshold) of the blood flow changes was 8%.
This study shows for the first time in human autoregulation of Fonh when PPm is increased by increasing the systemic blood pressure.
动物和人类研究均已证实，视神经乳头血流（Fonh）会因灌注压降低而发生自动调节。本研究旨在确定全身血压升高时Fonh的变化情况。
采用激光多普勒血流仪，对13名正常受试者（年龄16至58岁）单眼的血流参数进行测量，这些参数包括视神经乳头组织中红细胞的相对平均速度、数量和通量（分别为Velonh、Volonh和Fonh），测量时间点为基线、蹲起等长运动期间及运动后。采用血压计测量肱动脉血压。在基线和蹲起结束时测量眼压。
蹲起过程中，平均动脉压从103±6 mmHg升高至139±58 mmHg（平均值±95%置信区间），眼压从13±0.5 mmHg升高至17±1 mmHg。灌注压均值（PPm）从56±4 mmHg平均升高至80±7 mmHg，未引起血流参数的显著变化（p>0.05）。血流变化的敏感度（检测阈值）为8%。
本研究首次表明，在人体中，当通过升高全身血压使PPm升高时，Fonh会发生自动调节。
