What is Glaucoma?
Glaucoma is a complicated group of eye diseases that gradually cause sight to deteriorate and eventually lead to blindness, nicknamed the ‘sneak thief of sight’. Glaucoma is the leading cause of blindness, affecting over 60 million people worldwide. Unfortunately, when sight is lost the loss is permanent and because there are no symptoms in the early stages, up to 40% of vision can be lost without a diagnosis.
There are three main types of Glaucoma: primary, secondary, and developmental. Developmental glaucoma is glaucoma that affects babies and children and affects about five in every 100,000 children.
Primary glaucoma can be further split into two categories: Primary Open Angle Glaucoma (POAG) and Primary Angle Closure Glaucoma (PACG). Both of these types affect the pressure in the eye. Eye pressure is controlled by aqueous humor, a watery fluid which is made in a ring of tissue that sits behind the iris called the ciliary body. This fluid flows through the pupil and then drains away through tiny channels called the trabecular network in the angle between the cornea and the iris. In healthy eyes, there is an equal balance between inflow and outflow liquid, but in some eyes this balance is disturbed which causes eye pressure to rise and causes damage to the optic nerve.
In POAG, the most common form of glaucoma, the outflow of liquid doesn’t work as well as it should which increases eye pressure, and this form of glaucoma is often gradual and symptomless in the early stages. In PACG, the drainage angle is narrower which can slow down or even stop the outflow of liquid completely; this form of glaucoma is more related to the shape and size of the eye itself and can be acute or chronic. Symptoms for acute PACG include intense pain, redness of the eye, blurred or reduced vision, headache, and nausea, whereas symptoms for chronic PACG include blurred vision, halos around lights and headaches.
Secondary glaucoma is similar to POAG in that issues arise when the outflow of liquid doesn’t work as well as it should, causing a build-up of fluid and increased eye pressure. However, it differs in that when the underlying cause of the increased pressure is treated or cured then pressure may return to normal, although if the pressure has already caused damage to the optic nerve, then any damage is permanent. There are many different causes for secondary glaucoma, including Secondary Ocular Hypertension when there is an increased pressure in the eye but no detectable damage to the optic nerve.
Diagnosis and Treatment:
Anyone can develop glaucoma so it’s important to attend regular check-ups at an optometrist even if you currently have no need for glasses as, for most people, the first signs of glaucoma are spotted at routine check-ups. You should have a routine eye test every two years.
While anyone can develop glaucoma, several risk factors make it more likely: age (it is most common in adults in their 70s-80s), family history (people with close relative that have glaucoma are at increased risk), ethnicity (people of African, Caribbean, or Asian origin are at increased risk) and other medical conditions (short-sightedness, long-sightedness, and diabetes for example).
Any sight-loss due to glaucoma is permanent but there are some ways to treat it; treatment will depend on which type of glaucoma a person is diagnosed with. Treatments include eye drops, surgery, and laser treatment. Eyedrops are the most common treatment for glaucoma and are used to reduce the pressure in the eyes by either increasing the drainage of fluid or reducing the amount of fluid made. Laser treatment is used to treat POAG and Ocular Hypertension by opening the drainage channel in the eye to increase the outflow of liquid and relieve pressure in the eye. Surgery can also be used to improve the drainage of fluid from the eye and involves helping to drain the fluid from the eye into a small blister called a bleb under the eye, creating a sort of trap-door for fluid to drain through instead of the normal drainage channel.
Whether you know someone who suffers from glaucoma or not, there are many way to get involved and help to end glaucoma sight loss. As there is no cure and the exact causes of glaucoma are still unknown, research is vital.
In the UK, there are plenty of fundraising opportunities and becoming a member of Glaucoma UK means you will be the first to hear about any events or activities as well as allowing you to stay up to date with research and access to their quarterly magazine – become a member HERE.
Fundraising is important there are many ways to help; planning your own fundraiser like a head-shave or sponsored activity is a good idea as well as organised challenge events like the London Marathon. You can fundraise online by setting up a Just Giving page here or make a single donation here or if you are in the US you can donate to the Glaucoma Research Foundation here.