Glaucoma may be source of your blurred vision

Early detection, through regular and complete eye exams, is the key to protecting your vision.

What you need to know:

Glaucoma is a complicated disease in which damage to the optic nerve leads to progressive, irreversible vision loss. It is also the second leading cause of blindness. There are typically no early warning signs or symptoms of open-angle glaucoma. However, new interventions show that all hope is not lost.

Okello Owino, 65, mistaking glaucoma for ordinary eye effects that come as a result of old age, only sought medical attention after his blurring sight vanished, following two years of deteriorating eye sight. The least he can do is trace opaque objects around him.
“I can only see some little light on the wall,” Okello says, adding that at first he did not take it seriously thinking it was old age taking toll on him.

Okello, a civil engineer by profession says, “one of my eyes was operated but I am yet to see any improvement.”
Irresolute about his fate, Okello, also a former civil servant, has retired and relies on his children for upkeep.
With the guide of a mobility aid, Okello is led by his grandson every time he has to go to Mulago hospital for review.
He remains hopeful that one day he will regain his sight and go about his business, however, doctors say this is far from possible.

What is glaucoma?
According to Dr Angella Nakandi Lwanga, a senior consultant Ophthalmologist (eye surgeon) at Naguru referral hospital, Glaucoma is a disease that damages your eye’s optic nerve. She says, “it usually happens when fluid builds up in the front part of your eye.” She explains that permanent loss of vision caused by glaucoma cannot be reversed.
The pressure in the normal eye, Dr Nakandi says, is between 10-20 millilitres of mercury but any pressure above 20, “we assume a patient has glaucoma.”
Although majority causes of glaucoma are not known, in some instances, glaucoma is due to trauma, injuries and other related diseases in the eye such as inflammation and cataracts, Dr Nakandi says.

The eyebrow, Dr Nakandi says, takes in fluids which nourish inside the eye and are supposed to come out in equal measures but for patients with glaucoma, for some, the water entering is too much and does not come out in equal measures.
“For those glaucoma cases in which causes are not known, we think that the channels which bring out water inside the eye are either narrow or blocked such that what enters the eye is more than what comes out,” she says.
Dr Nakandi adds that in almost 60 per cent of glaucoma cases, their causes are not known.

Types of glaucoma
Glaucoma is classified in two types, open angle and angle closure glaucoma.
With open glaucoma, Dr Nakandi says, the channels in which the fluid flows out are open but the small channels where the fluids in the eye flow out are thought to be narrow.
“But nobody has really come up with proper explanation and shown they are narrow.”

Meanwhile, Dr Nakandi says, patients with angle closure glaucoma, the eyelid turns and closes the angle especially in the evening when the pupil is dilated and closes the angle, the pressure raises
Open angle however, is more dangerous because it presents with painless symptoms whereas the close angle glaucoma presents with painful symptoms which force people to seek treatment in early stages, she says.
She adds that: “With open angle, by the time someone realises they have remained with minimal sight, the glaucoma is advanced. At such times, the patients start bumping to things.”

Treatment
Dr Jacob Ntende, an ophthalmologist at Mulago National Referral Hospital’s eye clinic says patients are treated with drugs though sometimes surgery is performed on the eyes.
“These drugs are taken for life so that the patient does not to lose the remaining sight, “he says, adding that this usually applies to open angle and angle closure glaucoma.
On the other hand, Dr Nakandi says, surgery is usually conducted on the secondary category of glaucoma which is usually due to eye infections such as inflammation among other causes.
“If the glaucoma is a result of the other eye defects, surgery is done to correct the deffects, for example, the leaking lens,” she says, it is because with secondary glaucoma you are treating the causes which you know.

Unlike the other common eye diseases such as cataract and refractive errors, among others, with glaucoma, once the sight is lost, it cannot be recovered even with treatment, Dr Ntende says.
“The best that can be done is to preserve the remaining vision,” he explains that: “glaucoma causes permanent blindness and the patient has to depend on drugs for life.”
In case of any remaining vision, however, the patient, he says, has to remain under constant review to prevent glaucoma from worsening.
In babies this condition can be easily diagnosed because the eyes are still soft that when the pressure rises the eye brows become bigger. This Dr Ntende says helps babies escape permanent blindness.

Risk groups

According to Dr Ntende, relatives with glaucoma patients are advised to carry out annual checkups since most of the glaucoma cases are hereditary.
“But again, we see it’s more common among diabetics,” he says adding that patients with diabetes have a predisposition for glaucoma.”
Smokers too are also more exposed than others, he notes. But, glaucoma, especially in developing countries is degenerated due to late presentation of the symptoms since it is painless. “We think someone can stay with glaucoma for even 20 years because sometimes it’s slow and progressive,”Dr Nakandi says.

Prevalence in Uganda

Dr Ntende says most patients realise they are suffering from glaucoma after they have reached their 40s and when the disease has already advanced.
In terms of prevalence, at Mulago National Referral Hospital’s eye clinic alone, Dr Ntende says four out of every 10 patients who visit the clinic suffer from glaucoma.
According to the US-based National Center for Biotechnology Information (NCBI), in Uganda, glaucoma accounts for 3.6 per cent causes of blindness with the open angle glaucoma being the second leading cause of incident blindness.
A report by the World Health Organisation (WHO), glaucoma comes second after cataracts in causing blindness worldwide at 12.3 per cent while the latter is at 47.8 per cent.
Other ageing-related diseases include macular degeneration or AMD at (8.7%). Diabetic retinopathy (4.8%), however, according to WHO, has now began to predominate as causes of blindness.

Test to spot early glaucoma signs

Computer software to spot signs of glaucoma earlier than conventional tests is being developed by UK experts.
The team at London’s Moorfields Eye Hospital say the test has the potential to prevent many patients going blind.
Diagnosing glaucoma can be difficult, as patients are often not aware of symptoms until a great deal of useful sight has been permanently destroyed.

It is estimated glaucoma affects 67m people worldwide, including 500,000 in the UK - but only half are diagnosed.
This has led to glaucoma being dubbed the “silent blinding disease”.
It is estimated that if just 10 per cent of UK glaucoma cases were detected and treated earlier it could save up to £1bn a year.
If diagnosed in time, the condition can be easily treated with eye drops.
The condition causes damage to the optic nerve which carries visual information from the eye to the brain.

Over the Internet
The Moorfields Motion Detection Test (MDT) is designed to assess the field of vision.The software can be downloaded to a laptop computer, and eventually it is hoped to make it available directly from the internet.
A central white spot and several white lines are displayed on a grey screen.

The patient is asked to look steadily at the central spot and to press the computer mouse each time one of the lines is seen to move.
The lines move at the same speed but move different distances as the test proceeds, meaning experts can detect the degree of visual loss.
Moorfields say the test is affordable, portable, quick - and has the potential to spot glaucoma earlier than conventional tests, and with greater accuracy.
Steve Winyard, from the RNIB, said current tests often inaccurately diagnosed a problem in people who did not have glaucoma. He said the new test promised to be more accurate.

Jab that can cure glaucoma

Glaucoma can now be cured with a simple injection, according to eye surgeons.
They have started using an innovative method to relieve pressure in the eye – the most common cause of the sight-robbing condition – which does away with the need for scalpels and stitches.
It involves using a hypodermic needle to inject a tiny pliable drainage tube into the eye, allowing excess fluid to flow out.
Experts last night hailed the tube, called the Xen Gel Stent, as one of the biggest breakthroughs in the treatment of moderate to severe glaucoma in years.

Vik Sharma, a consultant eye surgeon at the Royal Free Hospital in London, said it was ‘quicker and safer’ than current methods. Keith Barton, of Moorfields Eye Hospital, added: ‘I can see this being taken up more and more in the NHS.’
glaucoma, a permanent narrowing of vision usually caused by damage to the optic nerve, resulting from an excessive build-up of liquid in the eye. As nerve damage gets worse, vision progressively narrows. Eye drops are usually given first to those at risk of glaucoma, but used alone these often fail to control eye pressure well enough.
Many then undergo laser eye surgery, but this can also fail to work.

Thousands end up having a trabeculectomy, a treatment that frequently involves installing a small rigid tube in the eye to drain it.
This is attached to a metal plate embedded below the eye, which helps draw the fluid away. The eye must be cut to insert these relatively bulky items, and stitched up again.
By comparison the Xen Gel Stent – described by Mr Barton as a ‘microscopic noodle’ – is delivered directly via a hypodermic needle into the eye. The tube is 6mm long and the width of a human hair.

The numbers
A total of 85 million people are estimated to be visually impaired worldwide: 39 million are blind and 246 have low vision.
About 90 per cent of the world’s visually impaired live in low-income settings. Eighty-two per cent of people living with blindness are aged 50 and above.
Globally, uncorrected refractive errors are the main cause of moderate and severe visual impairment; cataracts remain the leading cause of blindness in middle- and low-income countries.
The number of people visually impaired from infectious diseases has reduced in the last 20 years according to global estimates work. 80% of all visual impairment can be prevented or cured.