On the protective role of the blood vessels in glaucomatous damage: A transversal study

Purpose: To corroborate whether vessels on the surface of the optic nerve head can provide pro- tection against the loss of underlying axons in subjects with manifest glaucoma. Methods: In this pilot study, thirty-six glaucomatous eyes with a perimetric defect in the Bjerrum area were included. The retinal nerve fiber layer (RNFL) thickness was measured in each of the sectors of the clock-hour map obtained by Cirrus HD-OCT considering the presence or absence of blood vessels. These sectors were related with their corresponding areas of the retina examined in the visual field using a mathematical model of the retina introduced by Jansonius, in order to determine the values of threshold sensitivity in those areas in the presence or absence of vessels. Results: We corroborated the protective role of the blood vessel for peripapillary RNFL thickness of clock-hour 12 despite obtaining a p-value (p = 0.023; w = 228.5) close to the acceptance zone (p 0.05). The mean § standard deviation with vessel and without vessel were 70.95 § 24.35 and 88.46 § 23.96, respectively. No differences were found between the mean values of thresh-old sensitivity to the presence or absence of blood vessels in each of the sectors considered. Conclusions: Our findings do not allow us to affirm that there is an association between the pres- ence of a vessel and protection against glaucomatous damage in subjects with an advanced man- ifestation of the disease. In the future, more extensive studies are needed to study this relationship in subjects with early glaucoma.