Grunwald J E, Maguire A M, Dupont J
Department of Ophthalmology, Scheie Eye Institute, School of Medicine, University of Pennsylvania, Philadelphia 19104, USA.
Am J Ophthalmol. 1996 Oct;122(4):502-8. doi: 10.1016/s0002-9394(14)72109-9.
To investigate the retinal hemodynamic changes occurring in patients with retinitis pigmentosa (RP).
Bidirectional laser Doppler velocimetry and monochromatic fundus photography were used to determine retinal venous diameter (D), maximum erythrocyte velocity (Vmax), and volumetric blood flow (Q) in the major retinal veins of eight patients with RP and eight age-matched normal controls. The retinal vascular regulatory responses to hyperoxia, defined as the percent decreases in D (RD), Vmax (RVmax), and Q (RQ) at four to six minutes of breathing 100% oxygen, were determined in eight normal subjects and five RP patients.
Average D, Vmax, and Q +/- S.D. in the largest retinal vein of each subject were 106 +/- 14 microns, 1.01 +/- 0.20 cm/sec, and 3.5 +/- 1.3 microliters/min, respectively, in RP patients, and 166 +/- 12 microns, 1.79 +/- 0.14 cm/sec, and 14.7 +/- 2.6 microliters/min, respectively, in normal subjects. This corresponded to significant decreases from normal of 36% in D, 44% in Vmax, and 76% in Q in RP patients (Wilcoxon's rank sum test, P < .001). Average total retinal volumetric blood flow rate was 8.2 +/- 2.9 microliters/min in RP patients and 37 +/- 4.9 microliters/min in normal subjects, corresponding to a significant decrease from normal of 78% (Wilcoxon's rank sum test, P < .001). In RP patients, the regulatory responses to hyperoxia (RD, RVmax, and RQ) were similar to those observed in normal subjects.
Retinal blood flow is significantly decreased in patients with RP, probably as a result of vascular remodeling in response to reduced metabolic demand. The regulatory responses to hyperoxia are similar to those of normal subjects. Measurements of retinal blood flow may help assess the progression of the disease and the effects of treatment.
研究视网膜色素变性（RP）患者视网膜血流动力学变化。
采用双向激光多普勒测速仪和单色眼底摄影术，测定8例RP患者及8例年龄匹配的正常对照者视网膜主要静脉的视网膜静脉直径（D）、最大红细胞速度（Vmax）和容积血流量（Q）。在8名正常受试者和5名RP患者中，测定视网膜血管对高氧的调节反应，即呼吸100%氧气4至6分钟时D（RD）、Vmax（RVmax）和Q（RQ）的降低百分比。
RP患者中，每位受试者最大视网膜静脉的平均D、Vmax和Q±标准差分别为106±14微米、1.01±0.20厘米/秒和3.5±1.3微升/分钟，正常受试者分别为166±12微米、1.79±0.14厘米/秒和14.7±2.6微升/分钟。这相当于RP患者的D较正常降低36%、Vmax降低44%、Q降低76%（Wilcoxon秩和检验，P<.001）。RP患者的平均总视网膜容积血流率为8.2±2.9微升/分钟，正常受试者为37±4.9微升/分钟，较正常显著降低78%（Wilcoxon秩和检验，P<.001）。在RP患者中，对高氧的调节反应（RD、RVmax和RQ）与正常受试者相似。
RP患者视网膜血流显著减少，可能是对代谢需求降低的血管重塑所致。对高氧的调节反应与正常受试者相似。视网膜血流测量可能有助于评估疾病进展和治疗效果。
