ABSTRACT
Impairment of blood supply to the optic nerve head, retina and peripapillary choroid due to vascular dysregulation is considered an important cause of the progression of glaucoma.1,2 Pathological segmental vasoconstiction (ischaemia) followed by vasorelaxation (reperfusion damage) in the branches of the ciliary and the retinal arterioles represents the insufficiency of autoregulation.This, in addition to the fluctuation of the ocular perfusion pressure due to either intraocular pressure (IOP) spikes or transient decreases of the effective arterial pressure in the ophthalmic artery is considered a significant risk factor in glaucoma. In clinical practice, treatment of vascular dysregulation in the eye cannot be separated from the IOP-lowering medication, since no evidence-based special ocular vascular treatment is available at present. However, several of the IOP-lowering drugs do show vascular effects (beneficial or potentially dangerous for the glaucomatous eye) in in-vitro and in-vivo animal models. Knowledge of vascular effects of eye drops approved for IOP lowering in glaucoma has been increasing in the last years, although the published findings are sometimes contradictory, and some of the clinical techniques used to measure ocular blood flow require further development.
