Lanzl I M, Witta B, Kotliar K, Vilser W
Augenklinik und Poliklink der Technischen Universität München.
Klin Monbl Augenheilkd. 2000 Oct;217(4):231-5. doi: 10.1055/s-2000-10354.
Retinal vessel diameter assessment is complicated by various components among them dynamic changes due to vasomotoric effects. Measurement of these diameters was usually obtained from fundus photographs. Functional diameter changes induced by external stimuli were difficult to evaluate because of their dynamic nature. The Retinal Vessel Analyzer (RVA) allows continuous on-line measurement of those dynamic changes. Whether functional changes due to 100% O2 breathing can be assessed by RVA is investigated in this study.
Continuous on-line registration of retinal arterial and venous branch vessels was obtained in 10 healthy volunteers. A baseline was taken during the first minute. Then for 5 minutes 100% O2 was delivered by mask. Further recording ensued for 4 minutes, while breathing room air. Vessel diameter change in percent to baseline was calculated for each individual and for a mean of the group.
Each individual demonstrated vasoconstriction. The mean diameter reduction for the group was 6.5% for arteries and 15% for veins.
RVA allows assessment of functional retinal branch vessel reactions. Retinal branch vessels diameters are denominators for capillary perfusion. RVA might be able to demonstrate an individual vessel's regulation potential by purposeful stimulation to constrict and dilate. This property could be helpful in understanding pathophysiologic processes as well as improving diagnosis and therapeutic effects in diseases influencing ocular perfusion such as diabetes, retinal vessel occlusion or even glaucoma. Further evaluation of effects of systemic diseases might be an additional application of functional retinal vessel diameter assessment by RVA.
视网膜血管直径评估因各种因素而变得复杂，其中包括血管运动效应引起的动态变化。这些直径的测量通常是从眼底照片中获得的。由于其动态特性，由外部刺激引起的功能性直径变化很难评估。视网膜血管分析仪（RVA）可以对这些动态变化进行连续在线测量。本研究旨在探讨RVA能否评估100%吸氧引起的功能性变化。
对10名健康志愿者的视网膜动静脉分支血管进行连续在线记录。在第一分钟获取基线数据。然后通过面罩给予100%氧气5分钟。在呼吸室内空气的同时继续记录4分钟。计算每个个体以及该组平均值相对于基线的血管直径变化百分比。
每个个体均表现出血管收缩。该组动脉平均直径减小6.5%，静脉平均直径减小15%。
RVA能够评估视网膜分支血管的功能性反应。视网膜分支血管直径是毛细血管灌注的指标。通过有针对性地刺激血管收缩和舒张，RVA或许能够展示单个血管的调节潜能。这一特性可能有助于理解病理生理过程，以及改善对影响眼部灌注的疾病（如糖尿病、视网膜血管阻塞甚至青光眼）的诊断和治疗效果。对全身性疾病影响的进一步评估可能是RVA进行功能性视网膜血管直径评估的另一个应用方向。
