color doppler indices of orbital arterial flow in end-stage renal disease patients; are the changes related to chronic hemodialysis or chronic renal failure?

background endothelial injury is a well-known complication in chronic kidney disease (ckd) and hemodialysis. one of the sites in which early vascular changes may be detected is the retina. of course, these flow changes may not be detected in ophthalmologic exams, but it seems that color doppler sonography of retinal arteries may be helpful in these cases. objectives in previous studies on ckd patients who underwent chronic hemodialysis, hemodynamic changes were noted in retinal arteries, but no study has been performed to determine which of the two processes (ckd or chronic hemodialysis) can produce these changes. in this study, we tried to answer this question. patients and methods doppler ultrasonography of the orbital vasculature including the ophthalmic artery and the central retinal artery was carried out in 17 patients (34 eyes) with chronic renal failure (crf) who underwent hemodialysis, 17 patients (34 eyes) with crf without a history of hemodialysis and 17 normal patients (34 eyes). the peak systolic velocity (psv), end diastolic velocity (edv) and resistance index were measured excluding hypertensive, diabetic patients and patients with cardiovascular disease. results the mean psv and edv were lower only in the ophthalmic artery of crf patients irrespective of the history of hemodialysis (psv was 35.2 in hemodialysis, 38.8 in crf and 51.6 in normal patients, p value = 0.001 and edv was 7.4, 9.4, 11.8, respectively, p value = 0.001) with no significant difference in the resistance index of the ophthalmic artery and other parameters [edv, psv, resistance index (ri)] in the central retinal artery. conclusions the mean psv and dsv in the ophthalmic artery were lower only in the ophthalmic artery of crf patients regardless of the history of hemodialysis. no significant difference in the resistance index of the ophthalmic artery and other parameters (edv, psv) of the central retinal artery were noted between different groups. these findings suggest that microvascular disease and endothelial cell dysfunction of the orbital vasculature are related to crf and not to chronic hemodialysis.