[Imaging of retinal arteries with adaptative optics, feasibility and reproducibility]

Adaptative optic is a new non-invasive imaging technique that allows to measure arterioles wall thickness and diameter with a resolution near two microns. Our objectives were to evaluate the feasibility and the reproducibility of this technique in untreated hypertensive patients.

In 23 naive hypertensive patients and in 14 normotensives, the internal diameter (ID) and the wall thickness of the superior temporal artery were automatically measured. Those measurements were made on a temporal artery segment and led to determine a whole vessel cross sectional area (WCSA) and a wall to lumen ratio (WLR). Intra-observer reproducibility was evaluated by realizing three consecutive measurements in 14 subjects. Inter-observer reproducibility was assessed by two independent readers in 17 patients. Variation coefficient was calculated as SD/mean values. A comparison of retinal parameters was made between normal and hypertensive subjects.

Inter-observer reproducibility indicated a variation coefficient of 1.3% for ID, 3.7% for the WCSA and 3.2% for the WLR. Intra-observer reproducibility indicated a variation coefficient of 3.2% for the WLR. Arterial remodeling was present in hypertensive patients at baseline with a significantly increased WLR as compared to normal subjects (0.32 ± 0.04 vs. 0.26 ± 0.04; P<0.05), both population having the same ID.

Adaptative optics is feasible and reproducible technique. The possibility of a direct and non-invasive assessment of retinal arterioles must assess the attractions in this technique in hypertensive patients' care.