By JEFFARAH GIBSON
Tribune Features Writer
Glaucoma is one of leading causes of blindness and visual impairment. For this reason the ophthalmology division of the Princess Margaret Hospital will be raising awareness of the sight-stealing disease in the coming weeks.
Under the international theme “Beat Invisible Glaucoma”, the division, in-conjunction the Public Hospitals Authority, is celebrating Glaucoma Awareness Week 2020 during March 8-14. The main goal is to promote community awareness of the condition so that Bahamians know its affects and take a proactive stance in curbing it.
Glaucoma is the number one cause of irreversible blindness and is often referred to as the “silent thief of sight”. The condition affects over 60 million people.
“Glaucoma is really a group of eye conditions which all have in common optic nerve damage. That is, damage to the nerve connecting the eye to the brain. This damage results in the loss of specialised nerve cells called ganglion cells which currently we do not have the ability to replenish or restore. Even more important is the fact that only half of the people with glaucoma are actually aware of it. As much as 40 of an individual’s vision may be lost due to glaucoma without the individual even noticing,” said Dr Rana Greene, consultant ophthalmologist and glaucoma specialist of the division.
Dr Greene explained two of the most common forms of the condition are primary open angle glaucoma and angle-closure glaucoma.
“Just as the human body is filled with water, so the eye is filled with water called aqueous humour. The aqueous humour plays an essential role in the health of your eye, providing proteins, electrolytes and glucose to the various parts of the eye. The aqueous humour is continually produced in and drained from the eye, helping to maintain the shape and pressure of the eyeball,” she explained.
“The most common form of glaucoma is primary open angle glaucoma and it occurs as a result of resistance to the flow of aqueous humour in the eye through its normal pathways. Angle closure glaucoma occurs when the normal drainage pathways are actually occluded. In both instances, fluid pressure builds up in the eye resulting in optic nerve damage,” she told Tribune Health.
Primary open angle glaucoma has no symptoms and this is the reason glaucoma screening and regular eye exams are so important she said.
Persons at risk for angle closure glaucoma may also have no symptoms at first. However, in an acute angle closure glaucoma attack, people may experience severe eye pain, blurred vision, headaches, nausea, vomiting and they may see halos around lights.
As for the risk factors, Dr Greene said anyone can develop glaucoma, particularly individuals with high eye pressure. Those at risk include older people, people with family history of glaucoma, people of colour and diabetics. Other risks include nearsightedness (myopia), eye injury and steroid use. Newborns and young children may be affected by congenital glaucoma.
Throughout the week, the division will stress the importance of eye examinations ability to detect the condition in its early stages.
“During your eye exam your vision will be recorded and your eye pressure measured. The eye pressure of a healthy eye is 21mmHg or less. The drainage system may be evaluated using a contact lens. During a dilated eye exam with eye drops, the inside of the eye including the optic nerve will be evaluated. Routine tests for diagnosing and monitoring glaucoma include visual field tests to assess peripheral vision and optical coherence tomography (OCT) to assess for optic nerve damage. Pictures may be taken of the optic nerve. The thickness of the tissue at the front of the eye may also be measured as it may affect the eye pressure reading,” she said.
A diagnosis of glaucoma can mean to lower eye pressure to prevent or halt optic nerve damage.
“This may be achieved through medications such as eye drops and surgery inclusive of laser treatments and incisional surgery. Early detection is key and may prevent significant vision loss from glaucoma. Make an appointment today to get your eyes checked,” she said.