[Static retinal vessel analysis in acute blood pressure increase]. / Statische retinale Gefäßanalyse bei akutem Blutdruckanstieg.

ABSTRACT

BACKGROUND: The aim of this study was to examine the changes in static analysis of the retinal vasculature during an acute rise of blood pressure in young normal subjects. MATERIAL AND METHODS: An increase of blood pressure was induced in 30 young normal subjects (age 18 - 30 years) by physiological stress. Retinal fundus photographs were taken before and immediately after the stress. The central retinal artery equivalent (CRAE), the central retinal vein equivalent (CRVE) and the arterio-venous ratio (AVR) were calculated by automated vessel analysis software (Talia Technology, Lod, Israel). The same vessel segments were measured before and after the rise of blood pressure. RESULTS: At rest, mean CRAE was 97.3 ± 9.6 micrometer, CRVE 114.5 ± 12.5 micrometer and AVR 0.85 ± 0.08. The mean systemic perfusion pressure was elevated by physiological stress from a mean of 90.7 ± 7 mmHg by 18.0 ± 7.8 mmHg. The static retinal vessel analysis showed a constriction of the arteries by a mean of -1.3 ± 3.9 microns and a venous dilatation of 0.6 ± 7.2 microns. The retinal AVR was diminished significantly (p = 0.02) by -0.015 ± 0.032. The degree of arterial constriction - but not the change of AVR - correlated significantly (r = -0.39; p = 0.048) with the degree of rise of blood pressure. CONCLUSION: Retinal autoregulation during acute increase of blood pressure in young normal subjects can be measured by static retinal vessel analysis.