Glaucoma includes a group of eye diseases that are associated with increased pressure within the eyeball, causing damage to the optic nerve and deterioration of vision. In most people the increased pressure inside the eye results from disruption of the flow of aqueous fluid into and out of the eye. In other patients the damage may be caused by poor blood supply to the optic nerve fibres, a weakness in the structure of the optic nerve, or a problem in the health of the nerve fibres themselves. It is critically important to detect glaucoma early by regular eye examinations so that any damage can be kept to a minimum.
TYPES OF GLAUCOMA
- Chronic (primary or open-angle) glaucoma is the most common form. Damage to the eye progresses slowly and vision deteriorates gradually. Initially the peripheral vision is lost, however, the person remains unaware of the problem as one eye will cover for the other until the majority of nerve fibres have been destroyed, and a large part of vision has been lost. This damage is irreversible. Treatment cannot recover the vision that has been lost, but it can slow down the damage process.
- Acute (angle-closure) glaucoma. Acute glaucoma is when the pressure inside the eye rapidly increases due to the iris blocking the drainage system of the eye. Symptoms include pain, nausea, blurred vision and redness of the eye and immediate medical help should be sought. If treatment is delayed there can be permanent visual damage in a very short time.
- Low-tension or normal tension glaucoma. Optic nerve damage can occasionally occur in people with normal eye pressure. This form of glaucoma is treated in the same manner as open-angle glaucoma.
- Congenital glaucoma. This is a rare form of glaucoma caused by an abnormal drainage system. It can exist at birth or develop later. Parents may note that the child is sensitive to light, has enlarged and cloudy eyes, and excessive watering. Secondary glaucoma Glaucoma can develop as a result of other factors such as an eye injury, cataracts, or inflammation.
Some people have a higher risk of developing Glaucoma.
- a family history of glaucoma
- short sightedness (myopia)
- eye injuries
- blood pressure
- past or present use of cortisone drugs (steroids)
TESTS FOR GLAUCOMA
A glaucoma test usually includes the following:
- Screening by either our Orthoptist or Clinical Nurse – a brief history is noted, medications recorded
- Eye pressure check (tonometry)
- Visual Acuity – how far down the eye chart you can read
- Visual field test if required – this tests the sensitivity of the side vision, where glaucoma strikes first and is performed using the Humphrey Visual Field machine
- Performed every 12 months or as requested by Doctor
- Tests peripheral vision
- The Optic nerve becomes compressed due to increased pressure in the eye which causes loss of peripheral vision
- This test can be done at our rooms in Murdoch or Armadale
- Time – takes approximately 30 mins
The Heidelberg Retina Tomograph is a confocal laser scanning system for imaging of the anterior and posterior segments of the eye. It comprises three modules which can be used independently or combined with each other. The major routine clinical application is analysis of the optic nerve head structure for glaucoma diagnosis. A second application is in diabetes for the location and quantification of retinal edema.
The HRT system is tried-and-tested, versatile technology.