Glaucoma describes a group of conditions in which there is characteristic cupping of the optic disc with corresponding visual field defects
Josfyn Uba, Christine Onwuachumba and Gloria Ikegbule
As often said, ‘in the land of the blind, a one-eyed man is king.’ Similarly, in the land of the sighted, every man is king. It goes to say the eye is a reverend organ in the body, a sense organ that man fears losing.
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In some quarters, the eye is called the ‘lamp of the body.’ It is no wonder the Holy Book records this about the eye: “if the eye is healthy, the whole body will be full of light. But if the eye is bad, the body will be full of darkness.”
Many defects harm the eye spreading darkness over the body but the one doctors call the silent thief of the eye is glaucoma. It is a common eye condition where the optic nerve, which connects the eye to the brain, becomes damaged. It is usually caused by fluid building up in the front part of the eye, which increases pressure inside the eye.
Glaucoma can lead to loss of vision if it isn’t diagnosed and treated early. In medical terms, glaucoma describes a group of conditions in which there is characteristic cupping of the optic disc with corresponding visual field defects, due to retinal ganglion cell loss. It is a progressive condition and the most common cause of irreversible blindness worldwide. It is the second leading cause of blindness worldwide.
Glaucoma is said to be an eye disease that has no cure and leads to total blindness. This eye disease comes upon her victim like a thief in the night, appearing suddenly on one eye and attacking the other, if not nipped in the bud, to cause total blindness.
Based on these findings, Daily Sun sought the views of some renowned ophthalmologists in Nigeria on how best to tackle this dangerous eye disease.
Dr. Kunle Hassan, the Chief Medi-cal Director, Eye Foundation Hospital Group and Deseret Community Vision Institute, Ikeja, Lagos said after cataracts, glaucoma is the second most common condition diagnosed in his hospital.
He noted that glaucoma doesn’t usually cause any symptoms. For this reason, many people do not realise they have glaucoma, unless picked up during a routine eye test. This, he concluded, is why glaucoma is often called, the silent thief of sight.
Describing how it attacks a person, Dr. Hassan explained that glaucoma typically has no signs in the early stages. As the disease progresses, it usually damages the outer edge of the vision, working slowly inward. Without regular check-up the victim may not notice a problem until it is near the centre of the vision.
Interestingly, glaucoma, he continued, attacks males and females equally. Worldwide, glaucoma is known to affect those in their 70s and 80s. However in the black populations, glaucoma is mostly seen among people in their 40s. The reason for this is not known exactly, but glaucoma tends to occur at a younger ages and is more aggressive in black populations.
Another amazing revelation by Dr. Hassan, who is the Past President, Africa Ophthalmology Council and member, International Council of Ophthalmology Emeritus Group, is that no particular food or drink contributes to causing glaucoma. And there is a possibility of a patient getting into depression or attempting suicide on account of being diagnosed of glaucoma especially at a late stage.
He explained that the only modifiable risk factor for glaucoma is intraocular pressure. However, this eye disease can also occur in patients with normal pressures. Other possible factors include Ischemia, which is the lack of oxygenated blood supply to the optic head.
He pointed that there is a greater prevalence of glaucoma in the southern regions, adding that a person is more at risk of developing glaucoma if a family member has it, hence, he advised that if a family member is diagnosed with glaucoma, their siblings and children should go for an eye exam once a year to be screened for it.
He said: “Glaucoma cannot be cured or prevented, but can be detected early by going for yearly eye examinations. Its management helps to preserve vision, by reducing intraocular pressure to a safe level specific to the individual patient. It is also important to realise that all interventions for glaucoma, whether eye drops, laser or surgery, are aimed at reducing the intraocular pressure.
“Glaucoma treatment should begin as early as possible. Once diagnosed, patients should adhere to the eye drops prescribed. It is dangerous stopping the use of medication as it can lead to irreversible blindness. In some cases surgery is indicated if pressures are difficult to control, or if a patient has difficulty complying with medications. Where the patient is young and the glaucoma is aggressive, surgery might be the first option in order to reduce the pressure.
“Awareness is extremely important. Most people will not experience symptom until a great deal of damage has already been done to the nerve. To prevent this, please see an ophthalmologist once a year for an eye exam. If examined and there is a suspicion of glaucoma, the relevant tests can be done and treatment started before you start to notice a problem with your vision.
“Basically, the importance of people coming for screening early, and having yearly eye checks is so that this eye defect can be prevented and good vision can still be preserved. And those who have been diagnosed at a late stage, there are low vision clinic available to help make the best of what vision the patient has left if severely vision impaired. There are also rehabilitation centers that can help patients adapt to being blind and if depressed, it often helps to speak to a psychologist or a psychiatrist.”
According to a Delta State-based expert in ophthalmology, the cause of glaucoma is unknown. However he noted that there are some causal factors.
The first, which is age, he says, is common among people above 40 years. Another one is hereditary. Furthermore, if a family member has had it, there is a higher chance of it also affecting other family members or siblings.
Having been in the profession in the last 20 years, Dr. Hassan said those who have eye diseases constitute approximately about one percent of the world population, and out of this one percent, glaucoma accounts for about 59 percent. It is the leading cause of irreversible blindness in the world.
Another eye specialist, who chose to be anonymous, argued that “glaucoma is a very dangerous eye defect because it has no symptoms initially. Before it starts giving the patient problem, the person would have lost over 80 percent of his vision. At this point, it does not cause pain, has no redness or itch. Even the sufferer does not know that he is losing his vision which is why it is called the thief of the eye.”
He continued that there are variants of glaucoma. According to him, there is close angle and open angle types.
“Close angle glaucoma is not common in this part of the world. What we have here is open angle glaucoma with no pains, no headache until very late when the patient starts noticing that everywhere is hazy and smoky. The worst is that any part of your vision lost to glaucoma is irreversible,” he said.
The expert pointed out that those who say glaucoma cannot be operated upon are completely ignorant of the disease and are not properly briefed on how to manage it.
He affirmed that the best approach to managing glaucoma was surgery, while noting that before an eye doctor operates a patient, he should make the patient realise that even after the surgery he is not going to see better that he was seeing before.
“And the doctor must define to the patient the purpose of the operation, which is, to preserve what is left of his vision and not to regain what he had lost. But, if he does not do this operation, the chances of him losing his vision is high,” he said.
Admonishing further he said: “A glaucoma patient who opts for eye drops in the treatment of the eye defect is more like postponing the evil day. How long are you going to use it? At a point, you will get tired of using eye drops and it is not going to stop the disease either.
“As soon as you are up to 40, regular examination of the eyes is very important because the damage done by glaucoma is gradual.”
Also sharing his experience on glaucoma, Dr. Sunday Abu, Chief Medical Director, Havillah Eye Hospital, Abuja, told Daily Sun that majority of people come late for treatment at a time when they cannot help them.
According to him, “it is important for everyone to understand that glaucoma is a silent disease; people are not aware of it. People come to the hospital only when they notice that something is obviously wrong with their eyes, including very learned people.
“The bottom line is for people to go for early detection. For this to happen, people must bring themselves for check-ups in the hospital when everything seems normal. It is also important that awareness be created so that people will know the implications of delay. It is only when it is detected early that something can be done.”
Putting the ratio of people suffering from this disease worldwide at 16 percent, Dr. Abu said glaucoma was prevalent in every region but the mode of presentation may differ. In communities where people take their health matters seriously, they may come early to see the doctor and he may be able to salvage the situation, he said.
Said he: “Glaucoma is symptomless until late stages. When you wait to see the symptoms, it would have been late. The symptom usually is that one cannot see well with the eyes and at that point, it is already late.
“The point is that people should go for checks when nothing seems to be happening. It will only take a sense of willingness for people to walk into the hospital for an eye check when everything appears normal. Those are the ones you can catch early and do something about, but those that wait to see symptoms before they come to the hospital would have presented very late.
“There are different types of glaucoma. There is glaucoma associated with trauma but it is not the one we are talking about. This one we are talking about has an unknown cause. It is a chronic disease in the eye and you can’t find any history of anything that has happened to the eye.
“It is good to also note that glaucoma can be genetic. In 10 percent of people who suffer from glaucoma, it runs in their family. If you have a relation who has suffered from glaucoma, it is an indication that you can have it, hence, your determination to go to the ophthalmologist for checks should be more than the person who has no relative suffering from it,” he noted.”
Talking about misdiagnosis in the detection of glaucoma, Dr. Abu said it is possible in Nigeria going by lackadaisical attitude of some health practitioners.
According to him, “you see different categories of people when you go to the hospital. There are different grades of eye care workers and it depends on who you are seeing. You would see people who would just give glasses and you go while you are harboring more serious problems.
“This is why creating of awareness on glaucoma should be part of our programme, generally, not only for the eyes but on other categories of diseases. There should be regular programmes in both print and electronic media for people to understand the seriousness of the disease.
“With Africa being home to superstition, dogmas and other types of cultural inhibitions, awareness should be able to break those barriers that keep people away from seeking medical attention. The fact that your father or relative died of an ailment doesn’t mean that you too should just sit at home and die the same way.
“As far as I am concerned, nobody wants to go blind. The fact that your father died blind is the major reason you should go for regular checks so that you don’t die blind.
“However, we cannot do much of awareness and enlightenment programmes without the government. With government apparatus, it becomes big enough to reach everybody.
This is to say, there is not much individuals can do. But if government collaborates with the private health sector, they both achieve the desired impact.”
Glaucoma: Patient speaks
Talking with a glaucoma patient gave an insight to the reality of the situation. Mr. Michael Bassey was a police officer with the Nigerian Police Force when he was diagnosed of glaucoma on his right eye in 2011.
He told Daily Sun that he had no inkling that he had the defect. He only recalled that on his way to work one morning, he felt something entered his eyes. It was not itching him; rather he noticed he was having blurry vision on the affected eye. He visited the hospital and after three weeks there, his eye was confirmed to have been affected by glaucoma at the Daughters of Charity Eye Clinic in Benin City.
Mr. Bassey who is presently retired accounted that the eye defect did not cause him his job as on-looker rarely noticed he had problem with his right eye.
He said: “Having glaucoma did not affect my job. Only my boss knew about my condition. My colleagues knew after my eye surgery when they saw me carrying a bandage.
“I consider myself lucky because once the eye goes bad, I can never recover the eye. It did not give me any sign, only that I noticed I was not seeing very well with that eye. I was told if I had not sorted for medical attention early, it would have deteriorated to affect my left eye.”
The retiree said he is on a continuous drug treatment to prevent the disease from spreading to the other eye.
Data analysis provided by College of Medicine, University of Ibadan, Oyo State, states that more than 100 thousand cases on glaucoma are recorded per year in Nigeria. It also said glaucoma, which can be chronic to last for years or lifetime rarely affect those between the ages of 14 and 18. However, very susceptible to being affected are those between the ages of 19 and above.
Data from population-based surveys indicate that glaucoma is the second leading cause of blindness, accounting for eight percent of blindness among the 39 million people who are blind worldwide.
In Africa, glaucoma accounts for 15 percent of blindness and it is the region with the highest prevalence of blindness relative to other regions worldwide. The national blindness survey in Nigeria in 2005-2007 glaucoma was the second commonest cause of blindness (16.7%) (prevalence 0.7%; 95% CI: 0.6-0.9).
Symptoms of glaucoma include blurred vision, or seeing rainbow-coloured circles around bright lights. Both eyes are usually affected, although it may be worse in one eye