Nutrient - Ginkgo for normal-tension glaucoma
Glaucoma is usually high pressure inside the eye that damages the optic nerve and can result in permanent vision loss. Normal-tension glaucoma (NTG) is a rarer, but no less destructive, form of glaucoma, in which optic nerve damage and vision loss have occurred, despite a normal pressure inside the eye.
Although its cause is not completely understood, NTG is generally believed to occur either because of an unusually fragile optic nerve or because of reduced blood flow to certain parts of the eye. For this reason, scientists in Italy have been looking at the possible use of the blood-flow-supporting herb Ginkgo biloba.
To investigate the effect of Ginkgo biloba on the visual problems of patients with NTG, the scientists performed a placebo-controlled, double-blind study. During the trial, 27 patients who had suffered eyesight problems due to NTG were given either 40mg Ginkgo biloba extract three times a day or a placebo for four weeks. After an eight-week gap the patients wapped groups. Visual tests were performed at the beginning and at the end of each phase of the study and the patients’ results were evaluated for changes.
As they expected, the scientists discovered that, after taking the Ginkgo biloba extract, patients showed significant improvements in the visual tests compared to before taking the extract. This is thought to be due to the Ginkgo extract aiding blood flow to a special part of the eye called the macula, which deals with fine vision and the optic nerve.
Quaranta L, Bettelli S, Uva M, Semeraro F, Turano R, Gandolfo E. Effect of Ginkgo Biloba extract on pre-existing visual field damage in normal-tension glaucoma. Ophthalmology. (2003)110(2):359-62