Ocular blood flow in glaucoma
| Eyes with glaucoma have less blood supply than healthy eyes. This reduction is partly the result of high eye pressure and / or glaucoma damage (Glaucomatous Optic Neuropathy = GON). But in glaucoma there are also circulatory disorders that have other causes and are causally involved in the development of the damage. The lower the eye pressure at which glaucoma damage occurs or progresses, the more significant are such primary circulatory dysfunctions. While we observe such disturbances more or less in all normal tension glaucoma patients, we find them in high tension glaucoma patients especially when the damage progresses despite normalized IOP. | |
 J Flammer: Glaucoma research, a retrospective of my journey (Video) |
That blood flow plays a role in glaucoma was doubted for decades. Today, this is generally accepted. A pioneer of modern vascular glaucoma research is Josef Flammer. Together with his team, he not only demonstrated that blood flow is altered, but was also the first to identify its causes and introduce new therapies. In his farewell lecture on the occasion of his retirement in 2013, he talks here in a video recording about the most important experiments and studies that led to these findings. |
 HJ Kaiser, A Schötzau, D Stümpfig, J Flammer: Blood-flow Velocities of the Extraocular Vessels in Patients with High-tension and Normal-tension Primary Open-angle Glaucoma |
In glaucoma, blood flow is not only reduced in the eye, but also in the vessels of the orbit that supply blood to the eye. Kaiser and Flammer were the first to show, using Color Doppler Imaging, that blood flow velocity is decreased not only in patients with normal tension glaucoma, but also in high tension glaucoma patients in whom visual field damage is progressive despite well-controlled intraocular pressure. In contrast, blood flow velocity in glaucoma patients with stable visual fields is the same as in healthy control subjects. |
 J Flammer, S Orgül: Optic Nerve Blood-Flow Abnormalities in Glaucoma |
Glaucoma causes various functional and morphological defects in the eye and brain. Blood flow is altered not only in the eye, but also in other organs. However, the most important damage in glaucoma develops in the optic nerve head. Accordingly, this review paper describes the anatomy, physiology, and pathophysiology of blood flow to the optic nerve head, as well as methods of measuring this local blood flow. It explains the causes of blood flow disorders and shows why they lead to glaucoma damage. |