Abstract
In Germany and France, Ginkgo biloba extract (GBE) has been used as a standard and authorized pharmaceutrical for the treatment of chronic cerebral circulatory insufficiency for about 30 years. GBE contains several flavonoids and terpenoids acting as free radical scavengers, vasodilators and enhancers of neurotransmission. GBE has recently proved to exert a favorable effect on cognitive and behavioral disturbance in patients with Alzheimer as well as vascular dementia. We examined the effect of GBE on local cerebral blood flow (LCBF) in 10 patients with chronic ischemic stroke and on their clinical status as well. The patients took 240 mg of GBE, daily p.o. for 4 weeks. Single photon emission tomography (123I IMP) was performed before and after the treatment. We placed 4 regions of interest (ROT, 8 mmΦ) in the bilateral cerebral cortices and cere-bellum and utilized the count ratio of the cortical ROls and cerebellum as a measure of the LCBF (CT: cerebel-lar index). Eight out of the 10 patients revealed an improvement of LCBF in the diseased hemisphere follow-ing the GBE treatment. The mean CI values before and after the treatment were 70.0±8.8% and 77.1±8.1%, respectively (p<0.05). The clinical symptoms and signs exhibiting a high improvement rate were as follows : headache (86%) dizziness (50%), depressive state (100%) and willingness (100%). The above data provide a cerebral circulatory basis for the clinical effectiveness of GBE. It is anticipated that Japanese neurologists, neurosurgeons and strokologists will come to recognize and understand this useful drug as one choice of treatment for stroke patients.
