Angle Closure Glaucoma

Angle-closure glaucoma is caused when the iris blocks the draining angle of the anterior chamber. The aqueous humor (the fluid that circulates in the anterior chamber of the eye) is normally drained through the trabeculum, a formation located in the corner of the anterior chamber, where the cornea (the clear window of the eye) meets the sclera (the white part of eye). When the iris blocks the angle, the drainage of the fluid is obstructed and the pressure in the eye rises either acutely or chronically. In both cases, if the patient does not receive the appropriate treatment in time, permanent damage to the optic nerve may occur which may even lead to a complete loss of vision.

Acute Angle Closure Glaucoma

It is an emergency and you must be examined immediately (the same day) by an ophthalmologist and receive the appropriate treatment.

The symptoms are the following:

– Sudden blurring of vision

– Intense pain in and around the eye

– Redness inside the eye

– Headache

– Nausea

– Vomiting

– Before the onset of the acute attack you may have seen bright halos around the lights

If you experience these symptoms, you can contact us immediately. The immediate reduction of intraocular pressure with eye drops and pills as well as laser iridotomy is required to avoid permanent damage to the optic nerve.

Chronic Angle Closure Glaucoma

In some cases the iris blocks the draining angle but the pressure gradually increases leading to chronic angle closure glaucoma. Unfortunately, in this case we have no warning symptoms and the only way to diagnose it is a regular ophthalmological examination that includes gonioscopy, i.e. examination of the angle of the anterior chamber with a special lens. About one-third of patients with chronic angle-closure glaucoma experience an acute glaucoma attack.

Main causes of angle-closure glaucoma

– A large crystalline lens (the lens that normally exists in the eye). Over time the lens becomes cloudy, causing the condition we call cataract but it also increases in size and can block the normal flow of aqueous humor through the pupil leading the iris to block the angle of the anterior chamber.

– The iris which may be thicker than normal

– The anatomy and adhesion of the iris to the eye may predispose to drainage obstruction (iris plateau)

Who is at risk of angle-closure glaucoma?

– People over 50 years old

– People who have a family history of angle-closure glaucoma (parents, siblings who are affected)

– Women are affected more often than men

– People suffering from farsightedness

– Patients taking certain medications: Medications such as certain types of antidepressants or antihistamines may increase the risk of angle-closure glaucoma.

– Patients with eye trauma or surgery: In some cases, previous eye trauma or surgery can lead to angle-closure glaucoma.

How is the diagnosis made?

The diagnosis of angle-closure glaucoma requires a complete eye examination. Simply measuring eye pressure is not enough for diagnosis.

During the examination, we measure visual acuity, eye pressure, corneal thickness and examine the angle of the anterior chamber with a special lens. In addition we examine the optic nerve. Most of the time we request some tests such as examination of the visual field, optical coherence tomography (OCT) of the optic nerve and the angle of the anterior chamber as well as in some cases measurement of the axial length of the eye. With all this information we can inform you whether you are at risk or suffering from angle-closure glaucoma.

What is the treatment?

Treatment of angle-closure glaucoma is primarily aimed at opening the angle of the anterior chamber either by laser or surgery.

In cases of acute angle-closure glaucoma, the first concern is to check the intraocular pressure and perform laser iridotomy (see link). We usually do laser iridotomy in the other eye as well to avoid the risk of developing acute glaucoma in that one as well. Then, we plan soon for cataract surgery in an attempt to open the drainage angle of the eye. (cataract surgery-link). If the pressure is not controlled after cataract surgery, glaucoma surgery such as trabeculectomy (link) or placement of an aqueous humor drainage device (link) is likely to be needed.