Abstract
Purpose: :
We found previously that roughness of the retinal vessel blood column measured along the vessel axis, termed longitudinal vessel profile (LVP), increases significantly in retinal arteries of anamnestically healthy volunteers with increasing age. Whether LVP is altered with age in retinal vessels of medically validated healthy persons is investigated in a representative cohort.
Methods: :
82 medically validated healthy volunteers were examined by Dynamic Vessel Analyzer (IMEDOS Systems, Jena, Germany) using flicker light stimulation. 3 age groups were formed: young (N=27, 30.5±4.3 years), middle age (N=28, 42.3±3.3 years) and seniors (N=27, 64.0±5.0 years). Included in the analysis were volunteers without medical vascular risk factors defined as: blood pressure<140/90 mmHg, HDL>35 mg/dl, LDL<190 mg/dl and glucose levels<110 mg/dl. Retinal arterial and venous diameters were measured along 1 mm vessel segments to obtain LVP. Differences were analysed using Fourier transformation.
Results: :
In all age groups power spectra of LVP of neither retinal arteries nor veins changed significantly during all stages of the vessel response to flicker stimulation. Differences in arterial LVP were revealed between the age groups. Compared to young persons with less pronounced waves with a period of 208 µm, seniors showed diminished waves with a period of 417 µm at all stages of the arterial reaction (p<0.05). Mid age subjects demonstrated more pronounced waves with a period of 750 µm. There were no significant differences in venous LVP between the age groups (p<0.05).
Conclusions: :
Our results represent the healthy aging process in retinal vessels. In contrast to retinal veins retinal arteries of validated healthy volunteers do undergo age related microstructural changes. Our previously found age-related increase of retinal arterial roughness in anamnestically healthy volunteers was not confirmed in a medically validated cohort. The reason for this fact might be that anamnestically healthy persons could suffer from diseases increasing the cardiovascular risk factors which usually accompany the aging processes but were so far unknown to the examined population, since they were lacking thorough medical work-up due to their general well-being.
Keywords: aging • blood supply • pathology: human