Gonioscopy is an eye examination to look
at the front part of your eye (anterior chamber) between the
cornea and the
iris . During gonioscopy, the drainage angle of your
eye is checked. Your doctor measures the drainage angle, its width, and checks
whether it is open or closed.
The drainage angle
appears normal, is wide open, and is not blocked.
The drainage angle looks narrow, is a slit, or is closed. This means that the angle is partially or completely blocked, or there's a risk that the angle will close in the future.
A partially or completely blocked drainage angle may mean that you have closed-angle glaucoma . There are many reasons that a drainage angle can be blocked. These include scar tissue, abnormal blood vessels, injury or infection, and extra color pigment of the iris.
What Affects the Test
Reasons you may not be able to
have the test or why the results may not be helpful include:
- You cannot sit or lie still during the
- You have an allergy to the medicine used to numb your eye
during the test.
What To Think About
Other tests may be done to check
for glaucoma or other eye problems. These tests include a slit lamp
examination, tonometry (which measures the pressure inside the eyeball),
ophthalmoscopy (which checks the optic nerve), and perimetry (which tests side
To learn more, see:
Ramos-Esteban JC, et al. (2009). Clinical examination of glaucoma. In M Yanoff, JS Duker, eds., Ophthalmology, 3rd ed., pp. 1117–1127. Edinburgh: Mosby Elsevier.
|Primary Medical Reviewer||Adam Husney, MD - Family Medicine|
|Specialist Medical Reviewer||Christopher J. Rudnisky, MD, MPH, FRCSC - Ophthalmology|
|Last Revised||February 28, 2012|