Gonioscopy is one of the special tests for glaucoma. During gonioscopy, your doctor checks the drainage angle of the eye. This is the area through which the fluid inside the eye circulates, maintaining your eye pressures.
Gonioscopy is essential to classify glaucoma into open angle, or closed angle type. This is essential in further management of the disease.
Why do I need a gonioscopy?
- In case your doctor notices that the anterior compartment or anterior chamber of your eyes is shallow, he or she will advise the test.
- Alternatively, if you are a glaucoma suspect, your doctor will need to perform the test. Gonioscopy is important for diagnosis, classification and management of glaucoma.
- If you have a history of trauma to the eye, the doctor will want to ensure that there is no scarring of the drainage angle of the eye, called angle recession.
- In case you have diabetic changes on your retina, your doctor may look for new blood vessels in the angle of the eye.
- If you are getting an ICL (implantable collamer lens) implantation for vision correction, you will require a check gonioscopy.
- In case you are on certain drugs which may precipitate angle closure, your doctor may want to perform a gonioscopy.
Is gonioscopy painful?
Your doctor will put local anesthetic drops in both your eyes which might sting a bit. Thereafter, you will feel no pain.
Gonioscopy, by itself, is a painless procedure, though you may find it slightly uncomfortable. You will feel a jelly like substance in your eye (just like the jelly used for ultrasound). In addition, you will also feel a slight pressure on the eye during the procedure.
You will notice that your vision is not clear for up to about fifteen to twenty minutes after the procedure. It returns to normal thereafter.
Most people tolerate this procedure remarkably well, in some people it may stimulate one the nerves (Vagus) and result in a temporary syncope or giddiness.
How is the test done?
After explaining the procedure to you, the doctor will instil the local anesthetic drops. She will then place a lens in your eye and instruct you to look straight ahead, or towards a particular direction. You will need to keep both your eyes open and look in the direction instructed. The doctor will switch off the lights during the procedure for more accurate results.
Once the procedure is over, you will be assisted in cleaning your eyes. Your doctor will then put a drop of antibiotic eye drops in each eye.
