Objective  To evaluate the effect of mean defects index in visual field on treating patients with controlled intraocular pressure  glaucoma  by Ginkgo biloba  capsules ; to analyze the relationship between mean defect index in visual field and the visual electrophysiology P-VEP

Method  Patients with the corrected visual ≥0.3 who were diagnosed primary open-angle glaucoma and acute angle-closure glaucoma after surgery with intraocular pressure controlled by medicines or surgery (after more than three months, intraocular pressure ≤ 21mmHg) and  visual field defect, were enrolled and randomly divided into test group and control group. The test group was treated with Ginkgo biloba capsule, the control group was treated with placebo capsule.  All the course of treatment was 24 weeks. By observing the visual field and visual electrophysiology before and after treatment by Ginkgo biloba capsules, evaluate the effect of mean defects index in visual field on treating patients with controlled intraocular pressure glaucoma.

Result  1. Efficacy of visual field MD:  After treatment, visual field MD of control group was 11.17±7.56.The MD difference before and after treatment was 0.10±3.00 (n=133). Visual field MD of test group was 9.73±6.98. The MD difference before and after treatment was1.04±2.78 (n=131). The difference was not statistically significant within control group, and it was statistically significant in test group. There was a statistically significant difference between the two groups.

2. Efficacy of MD in different degree of visual field defect:  After treatment, observed MD difference of the mild visual field defect, there was no significant difference between the two groups.  The difference was not statistically significant within control group, and it was statistically significant in test group.  Observed MD difference of the moderate visual field defect, there was no significant difference between the two groups. The difference was not statistically significant within control group, and the same as test group. Observed MD difference of the severe visual field defect, there was significant difference between the two groups.  The difference was not statistically significant within control group, and it was statistically significant in test group. 

3. Efficacy of P-VEP: After treatment, analyzed the amplitude of P-VEP0.5cpdN145, 1cpdN75 and 2cpdN145 between the two groups, there was no significant difference before and after treatment. The difference was not statistically significant within control group, and it was statistically significant in test group.

Conclusions

1. Ginkgo biloba capsule could maintain visual field stable of controlled intraocular pressure glaucoma, particularly for patients with mild visual field defect and severe visual field defect. And also it could improve the amplitude of P-VEP0.5cpdN145, 1cpdN75 and 2cpdN145. To patients with controlled intraocular pressure glaucoma and better vision, the vision MD, it was positively correlated between the maintenance of visual field MD and improvement of amplitude in electrophysiology P-VEP. The mechanism maybe depressing calcium flowing, and thus inhibit cell apoptosis.

2. Ginkgo biloba capsule includes total flavonol glycosides and terpene lactones of EGb, with blood circulation, inhibition of calcium level and other actions. It can protect the optic nerve.