Glaucoma is a disorder in which the optic nerve head at the back of the eye is damaged, leading to progressive, irreversible loss of peripheral vision. It is often, associated with an abnormally high pressure of the fluid in the eye (a high intraocular pressure or IOP) although some patients develop optic nerve damage at a relatively low intraocular pressure, while other patients may have a high intraocular pressure for years and yet never develop optic nerve head damage.
Untreated glaucoma leads to permanent damage of the optic nerve and a resultant visual field loss, which can progress to visual loss and ultimately to blindness.
A tonometer and slit lamp
Glaucoma can be divided into two main types: “open angle” and “closed angle” glaucoma. Closed angle glaucoma can occur suddenly and is often painful; visual loss can progress quickly but the discomfort often leads patients to seek medical attention before permanent damage occurs. Open angle glaucoma is the more common type prevalent in the U.K., affecting about 2% of the population over the age of 40. It is a chronic condition and tends to progress at a much slower rate and the patient may not notice that they have lost any visual field until the disease has become quite advanced.
Glaucoma is mainly treated with eye drops which can be very effective. Some patients require laser treatment (e.g. laser trabeculoplasty) and a small proportion require glaucoma drainage surgery (trabeculectomy), which is often undertaken under “twilight anaesthesia”. In all cases, the aim of the treatment is to lower the intraocular pressure and thereby limit further optic nerve damage and slow down further progression of the condition.
The Preserflo TM microshunt glaucoma drainage system
This is a very new treatment for the management of glaucoma.
It offers a number of advantages over more traditional surgical approaches to the treatment of glaucoma:
- Significant and sustained reduction of IOP through the globally accepted and well-studied subconjunctival outflow pathway
- Minimally invasive subconjunctival approach bypasses all potential aqueous outflow obstructions
- Relatively undisturbed ocular surface tissue available after the procedure, leaving all other treatment options available for the patient’s future care
Mr Leon Au is an expert in the use of stents for the management of glaucoma.