Regular eye exams best defense to detect glaucoma

Going for regular eye examinations are key in the early detection of glaucoma.

Glaucoma Awareness Week 2022 was this year marked from Saturday March 6 to Sunday March 12, and the week is aimed at raising awareness about this debilitating eye condition, which in the long run can lead to blindness.

The challenge in detecting and treating glaucoma is that it remains completely undetected unless people undergo regular eye examinations.

“If not screened for, patients usually notice that they have decreased vision once it has already progressed significantly,” says Dr Laurens van der Merwe, registrar at the Division of Ophthalmology, at the Tygerberg Academic Hospital.

He says reasons for the condition being so undetectable, is that glaucoma presents no early signs or symptoms, making early detection or diagnosis of the condition very difficult.

“The only way to know if you have early glaucoma is to get your eyes examined. Some subtypes of glaucoma can develop pain or blurry vision, but the most common type of primary open angle glaucoma does not cause any symptoms,” says Dr van der Merwe.

“It can progress over months to years and is known as ‘the silent thief of vision’.

He gives more insight on what exactly this silent thief is. “Glaucoma is a chronic eye disease that leads to progressive damage of the optic nerve. This causes gradual, irreversible loss of vision and can eventually lead to blindness,” explains Dr van der Merwe.

According to him, the main cause of glaucoma is an increase in the pressure of the eye, medically described, as an increase in the intraocular pressure. Once this pressure has built up, he says it results in glaucoma and this pressure can only be reduced with medical intervention.

Once glaucoma is eventually diagnosed, there is no cure for it and if left undiagnosed or untreated, says Dr van der Merwe, the condition can ultimately lead to blindness. Medical treatment, he explains will only be aimed at halting progression of the condition, thankfully the progression of the condition is fairly slow, and painless.

The prescribed treatment for this condition would require reducing the intraocular pressure, he says. “Reducing the pressure does not take away damage that has already occurred but aims to reduce or prevent further irreversible loss of vision. Your ophthalmologist will work out a target pressure which would be deemed a safe pressure to prevent further progression of the disease, this is done according to your specific risk factors.”

“The intraocular pressure can be reduced with eye drops, laser treatment or with a surgical procedure. If you use glaucoma eye drops you will have to use this for the rest of your life to keep the pressure down. Once you stop using drops the pressure will increase again and cause further progression.”

Even though, laser and surgeries can provide long term relief, he adds there might still be a need for the use of eye drops. “If you undergo surgery or laser, you may still need to use eye drops if the pressure is not adequately controlled, and you still need to monitor for progression of the disease.”

As eye examinations are key in early detection, there are other options available in absence of, or no access, to private optometry medical services.

The Western Cape Health Department offers screening services for glaucoma at healthcare facilities. Byron La Hoe, spokesperson for the department urged people to be vigilant of any changes in their eyesight.

“The department encourages all citizens to seek care immediately and have eyes tested should there be sudden changes in their vision – severe eye pain accompanied by experience a of loss of vision, decrease in vision, blurry vision, formation of halos around lights or difficulty focusing on distant or near objects. These symptoms may indicate acute glaucoma.”

He says the reactive treatment administered by the health facilities would be dependent on the severity of the condition.

“Should the client present at a Primary Health Care facility and report such symptoms, they would be examined and if acute glaucoma is suspected they would be urgently referred to Eye Casualty at a Tertiary Hospital such as Groote Schuur or Tygerberg Hospital for medical treatment. Surgery to prevent future acute glaucoma would occur later as required

“If a client reports a more gradual loss of vision, testing of vision and ophthalmic examination would be undertaken to exclude chronic glaucoma. If this is suspected, the client would be referred to a hospital eye clinic for measurement of ocular pressure. If glaucoma was confirmed treatment would be initiated.”

In addition to its regular screening and testing services at health care facilities, the department has added the Prevention of Blindness Programme which provides more specialised eye care services and includes treatment of conditions, such as childhood blindness, cataracts, glaucoma, and diabetic retinopathy.

There are no measures for preventing glaucoma, but Dr van der Merwe advised people to be aware of potential risk factors for developing the condition.

He emphasizes the increase in intraocular pressure as the most widely accepted risk factor, but there are others to be vigilant of.

“The most common risk factors being if someone else has glaucoma in your family, advancing age (older than 40 years of age), if you are from African ancestry, having a thinner than normal cornea (front part of the eye) or if you have low blood pressure at night.”

Medical research on glaucoma is a continuous process and a recent medical breakthrough, Dr van der Merwe says, is the introduction of two new eye drops in treatment of the eye condition. Other recent medical advancements include exploring alternative surgical devices and procedures, the focus being on less invasive procedures.”

“Advances in laser treatment procedures have also been made in recent years with the introduction of the SLT laser,” he reveals.

In conclusion he reiterates the importance of regular eye examinations to boost early detection. “Glaucoma cannot be prevented or cured, but by screening and starting treatment before visual loss occurs the disease progression can be slowed down.”