Tageszeitvariabilität der retinalen Gefässdurchmesser. Ein Vergleich zwischen Patienten mit kardiovaskulärer Grundkrankung und gesunder Kontrollgruppe

Background: Retinal microcirculation is affected early in the process of atherosclerosis. Retinal vessel caliber is an emerging cardiovascular risk factor. However, it is unclear whether the retinal vessel diameters show a day time variation. The purpose of the present study is to investigate the retinal vessel diameters in the course of the day in two different study populations and to compare the results between these two groups. Method: Retinal vessel diameters were assessed by means of a static retinal vessel analyzer (SVA-T) in 20 healthy persons and 27 patients with cardiovascular disease. Two applicable images were made of both eyes three times a day and the central retinal arteriolar equivalent (CRAE), the central retinal venular equivalent (CRVE) as well as the arteriolar to venular diameter ratio (AVR) were defined. Results: There is a day time variation of AVR in healthy persons (p=0.005) as well as in patients (p<0.001). The CRAE shows significant differences in patients (p=0.010) but not in healthy study participants (p=0.077). In CRVE no difference could be established (p=0.653 healthy, p=0.107 patients). There is a difference of day time variation in AVR between the study groups (p=0.017). For CRAE and CRVE there were no significant differences between groups (p=0.169 and p=0.465, respectively). Conclusions: It depends on which day time the static retinal microcirculation is assessed. There is a need of different standardized guidelines concerning the method in clinical practice and in further research for healthy persons and patients with cardiovascular disease.