Angle-closure glaucoma - what is it and how is it treated?

Angle-closure glaucoma is a critical eye condition that requires immediate medical attention to avoid permanent vision loss.

 

Mr Myer Mark Yodaiken, highly experienced consultant ophthalmologist, explains what is angle-closure glaucoma, its symptoms, how it’s diagnosed and the available treatments.

 

 

What is angle-closure glaucoma?

 

Angle-closure glaucoma is a type of glaucoma that occurs when the drainage angle in the eye, the area between the iris and cornea, becomes blocked or narrowed. This blockage obstructs the flow of aqueous humour, the fluid that nourishes the eye, which usually drains out through the angle. When this drainage is obstructed, the intraocular pressure (IOP) in the eye increases quickly, leading to an acute attack.

 

Unlike open-angle glaucoma, which develops gradually, angle-closure glaucoma can come on suddenly and is considered a medical emergency. If left untreated, the high IOP can damage the optic nerve, resulting in permanent vision loss.

 

What are the symptoms of angle-closure glaucoma?

 

The symptoms of angle-closure glaucoma can vary, but may include:

• intense, throbbing pain in the affected eye
• nausea and vomiting
• cloudy or blurred vision
• seeing halos or rainbow-coloured rings around lights
• redness in the affected eye
• a dull or throbbing headache

 

If you experience any of these symptoms, it’s crucial to seek emergency medical help as soon as possible.

 

How is angle-closure clinically diagnosed?

 

Your ophthalmologist will perform a comprehensive eye examination if they suspect that you have angle-closure glaucoma. Diagnostic tests may include:

• Tonometry: This test measures the IOP in the eye. A high IOP is indicative of angle-closure glaucoma.
• Gonioscopy: This test uses a special lens to view the drainage angle of the eye, which helps determine whether it’s open or closed. A narrow angle or one that’s completely blocked confirms the presence of angle-closure glaucoma.
• Visual field test: This test evaluates the peripheral (side vision). If the optic nerve is damaged by high IOP, you may experience vision loss in the outer parts of the visual field.
• Ophthalmoscopy: This test uses a special instrument to examine the optic nerve and assess whether any damage has occurred. Swelling or changes to the appearance of the optic nerve indicate glaucoma-related damage.

 

How is angle-closure treated?

 

The treatment of angle-closure glaucoma requires immediate action to lower IOP and prevent irreversible vision loss.

 

Emergency treatment

 

If you’re experiencing an acute angle-closure glaucoma attack, the first priority is to lower the IOP as quickly as possible. This is typically accomplished through the following methods:

• Medications: Oral carbonic anhydrase inhibitors (e.g. acetazolamide), beta-blockers, prostaglandin analogs or alpha agonists may be used to lower IOP in the eye.
• Hyperosmotic agents: In severe cases, hyperosmotic agents such as intravenous mannitol may be administered to pull fluid out of the eye, which rapidly reduces IOP.

 

Long-term management

 

Once the acute episode is controlled, a procedure called laser iridotomy may be performed to create a small hole in the peripheral iris, allowing the aqueous humour to drain properly and relieving IOP. This procedure is typically done on both eyes, even if only one eye was affected, to prevent potential attacks in the other eye.

 

After, you will need regular eye exams to monitor IOP and ensure the condition is under control. In some cases, medications may be prescribed on a long-term basis. The frequency of these follow-up appointments will depend; initially, more frequent visits may be required, but over time, visits will become less frequent.

 

 

To book an appointment with Mr Yodaiken, head on over to his Top Doctors profile today.