Glaucoma

Glaucoma can have no symptoms until there is significant irreversible visual loss. This stresses the importance of regular eye checks which can detect the condition before it causes damage to the nerve.

Tonometry
This tests the pressure within both eyes. The eye is numbed using eye drops, and a pressure reading contact lens is advanced until it lightly touches the surface of the eye, and the pressure is recorded.

Ophthalmoscopy
The second test is to directly visualise the optic disc (nerve) to assess whether it has any damage or not. This test is carried out in a darkened room, with the pupils dilated using eye drops and a small light shone inside the eye.

Your vision will become blurry for a few hours when your pupil is dilated, which will mean you can’t drive home straight after the test.

If the optic disc (nerve) looks normal, and the pressure is within the normal range, no further tests are needed. However, if the result of either test is unusual, you may be invited for some further tests.

Perimetry
As the name suggests, this tests your perimeter of vision known as the visual field. Glaucoma affects peripheral vision first, which is why most people are unaware there is a problem until the damage extends more centrally.

This test allows the examiner to detect whether there is any loss of peripheral vision before you may become aware of it.

Gonioscopy
This is a painless test using a lens with a mirror that allows the examiner to visualise the angle where the fluid flow can become blocked. The aim is to identify if the angle is narrowed or closed, or if it is normal.

If you are diagnosed as having Glaucoma you will be referred to a Moorfield’s Eye Hospital Glaucoma clinic, where you can choose the nearest clinic to you for ongoing treatment and care. There are clinics based on City Road in Old street, St Ann’s Hospital in Tottenham or Mile end hospital.

If the result is not clear for example, there is no evidence of Glaucoma but there is a family history or suspicious features, you will be asked to attend a follow-up appointment at Homerton Hospital in 6 months’ time so that this can be monitored.

If your test is negative you will be discharged from the service unless you have other eye conditions that require treatment by the Ophthalmology team.

Glaucoma treatment can vary from one individual to another, but is always aimed at reducing visual loss, which is usually done by reducing the pressure within the eye. Glaucoma can’t be cured, but early detection and treatment can prevent progression of visual loss. The treatment can be medical, laser or surgical. In the majority of cases, medical treatment can control the progression of glaucoma, and rarely is surgery required in the first instance.

Medical 
A range of eye drops that lower the pressure within the eye. It is not unusual to be on more than one eye drop at a time.

Laser 
In open angle glaucoma laser burns or holes can be made in the trabecular meshwork to increase drainage of fluid, or at the ciliary body to reduce production of fluid. In closed angle glaucoma the laser is aimed at the iris (the coloured part of the eye) to open the angle and improve the flow of fluid. 

Surgery
This is often considered if medical or laser treatment has not succeeded in reducing the pressure within the eye. For open angle glaucoma a trabeculectomy can be preformed. This involved creating a passage way for the fluid to exit the eye by bypassing the drainage system (trabecular meshwork). In cases where despite surgery the pressure still needs to be reduced further, a drainage implant can be considered.