WHAT IS GLAUCOMA?
Glaucoma is an asymptomatic condition that affects the nerve of the eye (optic nerve), and leads to irreversible visual loss. Due to the fact that this condition seldom causes pain, and causes a gradual loss of initially only peripheral vision, it is often only diagnosed late. Where the pressure inside the eye normally varies between 10 and 21 mmHg, the pressure in glaucomatous eyes increases to above 21 mmHg. This pressure rise is caused by an imbalance between the rate of secretion and absorption of the fluid in the eye.
People at an increased risk of developing glaucoma, e.g. previous eye trauma or inflammation, a family history of glaucoma, older than 65 years, nearsighted, use of steroid medication etc., should have regular eye examinations to exclude glaucoma. The diagnosis of glaucoma is not always easy to make, and depends on information attained from various examinations.
The measuring of the intra-ocular pressure and examination of the optic nerve for damage are essential, but also very important is the visual field examination that clearly indicates the blind areas in grey and black. Sometimes more specialised equipment like Ocular Coherence Tomography (OCT) and the Heidelberg Retinal Tomograph (HRT) is utilised to help in the diagnosis.
The OCT has become in indispensable tool in the diagnosis and treatment of glaucoma. The OCT can not only objectively measure the optic nerve to help diagnose glaucoma, it can also accurately determine any progressive changes of the optic nerve. With the Swept Source OCT it is also possible to accurately diagnose atypical presentations associated with glaucoma, in order to assure that the patient receives timely treatment. This is very important since the damage caused by glaucoma is irreversible.
Glaucoma treatment is very effective, and involves the lowering of the pressure inside the eye with eye drops. In instances where this is ineffective in preventing further visual loss, laser treatment and surgery is utilised.
Argon Laser Trabeculoplasty or ALT involves the application of laser burns to the drainage apparatus of the eye, thereby increasing the aqueous outflow and therefore lowering the intra-ocular pressure. The procedure is painless and done in an outpatient setting. It is used in isolation where it is not possible for the patient to use topical medication, or as an adjunct to topical medication where the latter does not give an optimal pressure lowering effect.
Cyclodiode laser treatment is another laser treatment that is very effective, but it is aimed at lowering the pressure inside the eye by reducing the fluid secreted. A small pen is rotated along the outside of the eye after anaesthesia has been provided.
Minimally Invasive Glaucoma Surgery or MIGS is a new kind of surgical treatment. As the name implies it is a gentle kind of drainage procedure. A small drainage device, barely visible with the naked eye, is inserted in the drainage area inside the eye. The procedure is often performed as part of a cataract procedure. The healing occurs very quickly, with minimal additional care needed.
With effective treatment, any further visual deterioration can be prevented. It is essential that this condition be diagnosed early, since damage to the optic nerve cannot be reversed, but only further damage prevented.