Research that more than meets the eye

New Technique Analyses Blood Flow in Glaucoma Patients

22-May-2014 - Austria

The link between blood flow in the retina and the development of glaucoma can now be measured accurately for the first time. This was made possible by the further development of an established measurement method, optical coherence tomography (OCT), which enables the visual assessment of the retina and has thus become an important diagnostic tool. It does not, however, provide any information about retinal function. With the support of the Austrian Science Fund FWF, a research team at the Medical University of Vienna has succeeded in making a significant improvement to the technique so that it can now also be used to measure the blood flow in the retina. The value of this information in the context of the progression of glaucoma is now being established in a comparative study.

Our eyes also come under considerable pressure at times – and suffer enormous damage as a result. Specifically, the nerve cells in the retina are affected by increased eye pressure (glaucoma). This leads to irreversible damage in the optic nerve head, the destruction of the nerve cells and visual field defects. However, raised eye pressure can also potentially cause a reduction in blood flow to the retinal tissue. The extent to which this mechanism is responsible for the death of the nerve cells is disputed. While raised eye pressure is acknowledged as the main cause, there are increasing indications that the retinal blood flow can also be a contributing factor. Due to the lack of reliable measuring methods, it was not possible to test retinal blood flow up to now. A research team at the Medical University of Vienna (MUW), with the support of the Austrian Science Fund FWF, has changed this and is now embarking on an initial study to confirm the role played by vascular factors in glaucoma.

Flow Measurement

Commenting on the study, its leader, Professor Leopold Schmetterer from the Center of Medical Physics and Biomedical Engineering at the MUW, explains: "For the first time we will be able to measure the absolute retinal blood flow in glaucoma patients. To do this, we are testing the hypothesis that the blood flow in the retina is reduced in glaucoma. At the same time we will also evaluate the technology we developed – in particular its suitability for the long-term analysis of retinal blood flow in individual patients."

The technology optimised by Prof. Schmetterer and his team is called "Fourier Domain Optical Doppler Tomography" (FDODT) and involves the further development of optical coherence tomography (OCT). In addition to recording cross-section images of the retina, the technique can now also be used to quantify the blood flow. Thanks to further optimisations by Prof. Schmetterer and his team, the method can now record the absolute blood flow in the retina and thereby provide information about its influence on glaucoma.

https://www.bionity.com/en/news/148356/research-that-more-than-meets-the-eye.html