Glaucoma Screening
At Clearsight Opticians, we can pick up glaucoma during your routine sight test. If the Optometrist suspects any sign of glaucoma, we then do further tests before referring you onwards to a hospital. We have an enhanced machine, called an OCT, which also picks up glaucoma 4 years in advance!
What is glaucoma?
Glaucoma refers to a group of eye conditions that cause damage to the optic nerve. This nerve transmits information from the retina, the light-sensitive layer in the eye, to the brain where it’s interpreted as images. Think of the retina as similar to the ‘film’ of a camera, where light is focused, and the optic nerve transmits this information.
All types of glaucoma share certain characteristics, including increased pressure within the eye, ‘cupping’ of the optic disc, and loss of peripheral vision. The presence of any two of these features typically indicates a significant risk of glaucoma.
What regulates eye pressure?
The eye primarily contains water-based substances and fluids. Inside the eye, there’s a ‘tap’ constantly producing fluid, located behind the iris (the colored part of the eye). This fluid, called ‘aqueous,’ is separate from tears and remains inside the eye. Additionally, the eye has a drainage system located at the front, between the cornea’s edge and the iris. Increased eye pressure results from either excessive fluid production or inadequate drainage, or a combination of both.
How does increased pressure harm the nerve?
The exact mechanism of nerve damage due to increased pressure is not fully understood. In acute glaucoma, sudden pressure spikes can lead to insufficient blood supply to the nerve head in the eye. There are various theories regarding the process of nerve damage.
However, lowering eye pressure is known to delay glaucoma progression. Lowering pressure in acute glaucoma cases can preserve sight in eyes otherwise at risk of vision loss.
How prevalent is glaucoma?
It’s one of the leading causes of blindness in the Western world and encompasses several types, including chronic simple glaucoma (the most common), acute glaucoma, congenital glaucoma, and secondary glaucomas resulting from other conditions or factors.
Who is susceptible to chronic glaucoma?
Several risk factors increase the likelihood of developing chronic glaucoma, including:
- Age: Chronic glaucoma is rare before age 40 but affects 1% of individuals over 40 and 5% over 65.
- Race: People of Afro-Caribbean descent face a heightened risk.
- Family History: Glaucoma has a genetic component, so individuals with affected close relatives should undergo regular check-ups.
- Myopia: Individuals with severe nearsightedness are at increased risk.
- Why is untreated chronic glaucoma sight-threatening?
- Chronic glaucoma typically presents no symptoms, leading to gradual vision loss without pain or noticeable changes until significant damage has occurred, often affecting peripheral vision first.
How is chronic glaucoma diagnosed?
Several tests aid in glaucoma detection, including eye pressure measurement, visual field examination, and optic nerve assessment, all performed painlessly by optometrists at our practice.
Is chronic glaucoma treatable?
Yes, daily eye drops or, in some cases, surgical intervention such as Trabeculectomy can effectively slow glaucoma progression.
Acute Glaucoma
What is acute glaucoma?
Acute glaucoma involves a sudden increase in eye pressure due to physical blockage of internal eye drainage channels at the angle where the cornea meets the iris, often termed ‘Angle Closure Glaucoma.’
What are the symptoms of acute glaucoma?
Symptoms include severe eye pain, particularly upon waking, eye redness, blurred vision, and seeing halos around lights, accompanied by nausea and vomiting.
How is acute glaucoma treated?
Initial treatment involves rapid pressure reduction with potent medications. Depending on the situation, subsequent treatment options may include eye drops, laser therapy, or surgery. Preventive measures are often taken in the other eye to avoid a similar acute attack.