In conjunction with World Glaucoma Week 2012, Ipoh Echo talks to Consultant Eye Surgeon Dr S.S. Gill about this “silent thief of sight ” – PART 4
Glaucoma as you know has been nicknamed the “silent thief of sight”. This disease results in permanent irreversible blindness in the affected eye(s) that often goes unnoticed until the loss of vision is significant.
What Is Unnoticed Loss Of Vision?
In some types of glaucoma such as Primary Open Angle Glaucoma and Normal Tension Glaucoma, the visual loss occurs very slowly without the patient ever noticing until the disease is in its advanced stage. You may wonder how a person can be losing vision without noticing it. Well, this is because the visual loss is from the periphery.
This peripheral visual loss is typically described as tunnel vision. Starting in the peripheral most part of the field of vision, the visual loss slowly starts encroaching into the central vision. This slowly progressing loss of vision is often unnoticed by the patient until a substantial amount of peripheral vision has been lost. Furthermore, glaucoma is “silent” without any acute pain or symptoms.
This picture simulates the early tunnel vision that a glaucoma patient may have and yet may not notice that there is peripheral loss of vision. A major part of the central vision is good and the patient is still able to see well. This peripheral loss of vision can only be detected by specialised testing called Perimetry or Visual Field Testing.
This picture shows advanced glaucoma. Most of the peripheral vision has been lost here. Only a small tunnel of vision is left. At this stage, the patient usually experiences difficulty moving around in poorly lit places or outdoors at night. Most people end up seeking treatment at this stage when such a significant vision loss has already occurred.
I have had patients walk into my Consultation complaining of poor vision in one eye. Following examination, the patient was found to have Primary Open Angle Glaucoma. The shocking part for such a patient is that whatever visual loss has occurred cannot be reversed. In other words, the vision that has been lost in the affected eye is lost permanently. It is for this reason that those above 40 years of age should have their eyes checked routinely as part of their general health screening.
Dr Gill will elaborate on the eye checks that are done for glaucoma in the next issue of the Ipoh Echo.
For more information, contact Gill Eye Specialist Centre at 05-5455582, email: firstname.lastname@example.org or visit www.fatimah.com.my.