A year ago, Mr H came to consult me regarding his deteriorating vision in his left eye. He was an avid badminton player but he noticed that he has been missing the shuttlecock lately. The reason was that the image of the shuttlecock appeared and disappeared intermittently.
I checked his vision. Though his corrected visual acuities were normal, the side vision in his left eye was greatly diminished; hence this explained why he had been missing the shuttlecock. A detailed eye examination revealed that his left optic nerve was cupped and pale. The water pressure in that eye was 30 mmHg; nearly twice that of the normal average.
A diagnosis of glaucoma was made and he was started on anti-glaucoma eyedrops to lower the water pressure in his left eye. A month later, the pressure dropped to 12 mmHg which is within the normal limit. Unfortunately, the damage to his side vision done could not be reversed.
WHAT IS GLAUCOMA
Glaucoma has been called ‘the silent thief of sight’ because the initial loss of vision is so gradual that it goes unnoticed until irreversible damage has occurred to one’s vision. Glaucoma develops when the production of fluid in the eye (aqueous humour) increases or when the drainage of this fluid is impaired. As a result, the water pressure in the eye rises continuously, compressing and damaging the optic nerve. Over time, it loses its function and this results in blindness.
TYPES OF GLAUCOMA
There are 2 common types of glaucoma:
1. Acute Glaucoma develops suddenly with pain, redness and blurring of vision. There may be associated headache, nausea and vomiting because of the sudden rise in water pressure. This develops because the drainage in the eye becomes closed suddenly.
2. Chronic Glaucoma on the other hand develops slowly and quietly. There are no warning signs and this condition may go undetected until irreversible damage occurs.
The eye specialist will check the water pressure using a special instrument called a tonometer. The optic nerves have to be assessed for any possible damage. Finally, a test of the side vision (perimetry) is done using a specialised equipment called a visual perimetry.
Once the diagnosis is confirmed, treatment with eyedrops begins almost immediately. Sometimes,
laser treatment is needed to improve the outflow of the fluid. Surgery is required when all these fail
to bring down the pressure.
As Glaucoma is a silent disease, most will not experience any pain nor have any specific symptoms.
Thus, it is important to go for regular eye checkups after the age of 50 and earlier if you belong to
the following high risk groups:
a) Family history of glaucoma
c) Using steroids on a long-term basis
d) Hypertensive or diabetic
On the occasion of World Glaucoma Awareness Week, Dr Goh Kong Yong takes to social media to spread awareness on the Silent Thief of Sight. A/Prof Goh boasts years of valuable experience in ophthalmology and neuro-ophthalmology, making him a highly-skilled surgeon in cataract surgery, general ophthalmology as well as eye conditions related to neurological and neuro-surgical conditions. He prides himself on having treated many Singaporean and foreign VIPs in his three decades of experience.