Primary angle closure glaucoma
What is primary angle closure glaucoma?
The most common type of glaucoma is called primary open angle glaucoma. This is when the drainage channel (located between the iris and the cornea) is open. When the drainage channel closes, the iris moves forwards and against the cornea, blocking the pathway to the drainage channel and causing the pressure in the eye to rise. If this pressure remains high for a period of time, the optic nerve can be damaged, which then leads to primary angle closure glaucoma.
There are a number of conditions that are closely related to primary angle closure:
Primary angle closure suspect – This is when tests show that the drainage channel in your eye is narrow and is at high risk of closing up at any time. This is more common in people with smaller shaped eyes where the iris is naturally closer to the cornea.
Acute angle closure – Primary angle closure is usually painless and occasionally causes symptoms of mild headaches. However, if the drainage channel suddenly closes and the pressure suddenly becomes very high, the signs and symptoms are usually severe. This is called acute angle closure.
What are the signs and symptoms of acute angle closure?
It is possible to experience an acute angle closure attack if you have been diagnosed with primary angle closure suspect or if you have primary angle closure and are waiting for treatment. It is therefore very important that you are aware of the signs and symptoms of an angle closure attack.
- intense pain of the eye
- sore or tender eye area
- redness of the eye
- blurred and reduced vision
- seeing coloured haloes around lights
What should I do if I am experiencing any of these symptoms?
If you are experiencing any of these symptoms, you should seek medical advice as soon as possible.
What treatment is available for primary angle closure?
The two main treatment options are laser peripheral iridotomy and cataract extraction surgery.
Laser peripheral iridotomy
In this procedure, a laser beam is used to create a small hole in the iris. This provides another route for the fluid to flow and pushes the iris backwards, in turn helping to open the drainage channel. For more information on this procedure, please read the laser peripheral iridotomy information sheet. If you do not have a copy of this leaflet, please ask at the reception or doctor caring for you.
When a cataract forms, the lens inside your eye slowly becomes thicker. This can push the iris forwards, causing the drainage channel to become narrower. In a cataract operation, the natural lens is removed and replaced by a thin artificial lens. This makes more room for the iris to move backwards and allows the drainage channels to open.
Both procedures are effective in the treatment of primary angle closure. Your doctor will discuss with you the treatment that is best for you.
You may be prescribed glaucoma medication in the form of drops and/or tablets, which should be taken daily to control your eye pressures until the day of your procedure.
Your eye pressures may remain high even after the procedure. In these instances, drops may be needed to lower the eye pressures forever.
What happens if I do not get treatment?
If the pressure in the eye remains high, extensive damage can occur to the optic nerve. This will lead to significant and permanent visual loss.