Study of Medical Treatment of Low-Pressure (Normal Tension) Glaucoma
Status:
Completed
Trial end date:
2004-05-01
Target enrollment:
Participant gender:
Summary
Low-pressure (normal tension) glaucoma is a type of open-angle glaucoma resulting in damage
to the optic nerve and abnormalities of the visual field. Eye (intraocular) pressure in this
type of glaucoma is not higher than that usually considered to be normal (less than 21 mmHg)
for the eye. The present treatment of low-pressure glaucoma is also directed to lowering the
"normal" eye pressure. Both medications in this study, brimonidine and timolol, lower eye
pressure.
Laboratory research over the past decade indicates the potential to treat glaucoma not only
by lowering eye pressure, but with treatments aimed at the damage occurring at the optic
nerve. One group of drugs, selective alpha2-adrenergic agonists, have been shown in
laboratory animals to protect against the effects of nerve damage following local stroke.
Brimonidine, one of the medications in the current study, is a selective alpha2-adrenergic
agonist which protects against damage to optic nerve in animal models of glaucoma..
The hypothesis of the present study is that brimonidine eye drops provide protection to the
damaged optic nerve independent of lowering eye pressure in patients with low-pressure
glaucoma. This will be determined by (1) measuring eye pressure, (2) performing visual field
examinations, and (3) examination of the optic nerve.