Abstract
Abstract: :
Purpose: To evaluate the effect of Ginkgo Biloba extract (GBE) on ocular and systemic hemodynamics in patients affected by primary open angle glaucoma (POAG). Methods: Thirty caucasian patients (12 male, 18 female, mean age 63±12 years, range 52–70 years) affected by POAG with intraocular pressure (IOP) well controlled by monotherapy with topical beta–blockers (IOP<20 mmHg), visual acuity >8/10 and a visual field stable for at least 1 year, were divided into two groups. Group 1 (15 patients) was treated with 40–mg GBE tablets (1 tablet a day) (Vasopt tablets, Bausch&Lomb Oftal, Catania, Italy) and topical betablockers BID. Group 2 (15 patients) was treated with ocular beta blockers alone. Before starting therapy (T0) and after 3 (TM3) and 6 months (TM6) of therapy, ocular blood flow (OBF Langham Tonograph, Langham Ophthalmic Technologies, Timonium, MD, USA), Peak Systolic Velocity (PSV) and Diastolic Velocity (EDV) by means of Eco–color Doppler (Sonoline Elegra, Siemens, Germany), blood pressure and IOP (Goldman applanation tonometer) were registered. For statistical analysis only the values of left eye were considered; differences between groups were evaluated by means of Student’s t–test. Results: Ocular Blood Flow (pOBF) significantly improved after 3 months (19.7±8.29 vs. 18.0±6.42 µl/sec, + 9.4% vs. T0) and six months (19.5±6.62, + 8.3% vs. T0) of therapy with GBE (p<0.05 vs. control group). EDV in the ophthalmic artery significantly improved in the GBE treated group (baseline: 7.14±0.65 cm/sec, T6M: 7.58±0.53 cm/sec, + 5.8%) (p<0.05%). PSV and EDV did not change significantly in the central retinal artery and short posterior ciliar arteries in either group. Intraocular pressure, arterial blood pressure, heart rate and ocular perfusion pressure did not change significantly in either group at T3M and T6M with respect to T0. Conclusions: Ginkgo Biloba extract significantly increased pOBF and EDV of ophthalmic artery in primary open angle glaucoma patients without any influence on intraocular pressure or arterial blood pressure. Our data agrees well with obtained by Chung et al. (J. Ocular Pharmacol. Ther., 1999) on healtly volunteers ad could explain the positive effect of GBE on the visual field of normal tension glaucoma patients showed by Quaranta et al. (Ophthalmology, 2003).
Keywords: neuroprotection • optic flow