To measure the diameter of the retinal arterial and venous caliber of normal Korean subjects and evaluate the factors affecting these diameters.

Fundus photography was performed on 152 normal Korean subjects. Central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE) were measured with a computer-based program (IVAN), and were used to investigate the relationship between the diameter and factors including age, gender, hypertension, diabetes, and smoking.

Among the study subjects, the CRVE was 209.33 ± 12.40 µm and the CRAE was 149.70 ± 9.01 µm. The CRVE and CRAE decreased with increasing age in all study subjects (both p < 0.001). There were significant gender differences in the CRVE and CRAE ( p = 0.002, p = 0.042, respectively). After adjusting for age and gender, the hypertension group showed smaller CRVE and CRAE than the non-hypertension group ( p = 0.038, p = 0.032, respectively). Smoking and diabetes were not significant factors affecting the CRAE and CRVE (both p > 0.05).

In our study group, retinal vascular caliber of normal Korean subjects decreased with aging. Retinal vascular caliber was affected by gender and hypertension, but not by smoking and diabetes.