Glaucoma is a very common cause of blindness in Nigeria but, when it is detected early, it can be prevented. Unfortunately, it is asymptomatic, and the awareness of glaucoma among people is quite poor.
Glaucoma is a group of eye diseases causing optic nerve damages. The optic nerve carries images from the retina, which is the specialized light sensing tissue, to the brain so we can see. In glaucoma, eye pressure plays a role in damaging the delicate nerve fibres of the optic nerve. When a significant number of nerve fibres are damaged, blind spots develop in the field of vision. Once nerve damage and visual loss occur, it is permanent.
According to the World Health Organisation (WHO), glaucoma is now the second leading cause of blindness globally, after cataracts. Glaucoma, however, presents perhaps an even greater public health challenge than cataracts, because the blindness it causes is irreversible.
Dr Abiola Oyeleye, the Vice Chairman, Ophthalmological Society of Nigeria (OSN), Lagos State chapter, and Consultant Ophthalmologist, the Eye Doctor’s Clinic, Lagos, said: “A lot of people may have heard of glaucoma, but they just say ‘it is an eye condition’. But it goes beyond that; it is the most common cause of irreversible blindness. That means if you are blind from glaucoma, nothing can be done to bring your sight back.
“In glaucoma, you don’t have symptoms. If you go for a routine eye check and they confirm that you have it, then treatment can commence on time. Everyone is at risk of glaucoma but high risk groups are adults from age 30.
Dr Oyeleye said: “Some people have glaucoma at age 10 or 20; some children are born with glaucoma but, usually, people have it when they get to the adult stage. So, one needs to go for regular eye check.”
In her words, the Associate professor of ophthalmology, Guinness Eye Centre, Dr Adeola Onakoya, said glaucoma is not just a blinding disease “but you may not know if you have it and, unfortunately, it may result into blindness if there is no quick intervention. So, it is better that from about the age of 35, you see an eye specialist, precisely an ophthalmologist, to examine your eyes in detail and then tell you whether you have glaucoma, or not.
“It is only through early detection that you can prevent blindness from glaucoma and, if it is not properly treated, could result into blindness, because it is naturally progressive.”
In Nigeria, the prevalence of glaucoma amongst those that are above 40 year is put at about four per cent, and the estimate is that that age group is about 20 per cent of the population.
“So, in a population of 150 million, it means 30 million people are predisposed to be affected, and of that 30 million, two million people are probably suffering from glaucoma and, out of that figure, 200,000 of them are blind in both eyes. That is just under estimation. There are more people who are blind from glaucoma,” Onakoya said.
However, Oyeleye said: “Glaucoma is treatable, but not curable. When you say treatable, it means you can prevent it and try to prevent it from getting worse. You can prevent it with eye drops or tablets (medication) or laser treatment or surgery, but someone who has glaucoma cannot take it away completely, that is why it is treatable, but not curable.