Hemodynamic evaluation of the optic nerve head in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy

Background: Although cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is considered a cerebrovascular disorder with almost exclusively neurological symptoms, arteriopathy is generalized and also involves the choroid and retina. Objective. To study optic nerve head microvascular function in CADASIL by assessing blood flow, volume, and velocity with a retina flowmeter. Patients and Methods: Scanning laser Doppler flowmetry permits the noninvasive assessment of relative blood velocity, volume, and flow in a sample volume of either retina or anterior optic nerve head. Measurements were performed in a first group of 9 eyes of 5 patients with CADASIL and a second group of 8 eyes of 4 healthy subjects. Hemodynamic parameters were computed in 4 quadrants of the optic disc (superior nasal, superior temporal, inferior nasal, and inferior temporal). The Wilcoxon rank sum test was used to assess differences in relative flow, volume, and velocity in each quadrant and between the 2 groups and differences in overall optic nerve head blood flow, volume, and velocity. Results. Patients with CADASIL had a significant decrease in overall blood flow and volume compared with healthy subjects (P <.05). The reduction in blood flow and volume was particularly significant in the superior and inferior temporal quadrants. No significant differences were found nasally between the patients and the control groups. Conclusion. Our results suggest that hemodynamic parameters are abnormal in the superficial nerve fiber layer of the optic nerve head of patients with CADASIL, especially in the temporal quadrants of the neuroretinal rim.