Wall cross-sectional area of retinal arterioles did not differ between the study groups.

Wall-to-lumen ratio of retinal arterioles was assessed in vivo using scanning laser Doppler flowmetry.

Blood pressure emerged as an important and independent determinant of wall-to-lumen ratio of retinal arterioles.

Alpha and beta zones of peripapillary atrophy and diameter of retinal arterioles were less clearly correlated.

Conclusion: Our results clearly demonstrate that salt intake influences the structure of retinal arterioles independent of blood pressure in treatment resistant hypertension.

The growth index, indicating the percentage of difference in average wall cross-sectional area of retinal arterioles between both groups, was 18%.

Retinal arterioles are similar to cerebral small vessels and retinopathy occurs secondary to increased blood-retinal barrier permeability.