Glaucoma, as you know, has been nicknamed the “silent thief of sight”. This disease, which results in permanent irreversible blindness in the affected eye(s), often goes unnoticed until the loss of vision is significant.
What are the types of glaucoma?
Glaucoma can be divided broadly into the following:
1) Primary Open Angle Glaucoma 3) Normal Tension Glaucoma
2) Angle Closure Glaucoma 4) Other Types of Glaucoma
PRIMARY OPEN ANGLE GLAUCOMA – presents silently, most common.
Open Angle & Normal Tension Glaucoma: eye looks normal, no obvious symptoms
Primary open angle glaucoma is also known as chronic glaucoma. This is the most common glaucoma type. It mainly affects adults over age 35. In most cases, by the time open angle glaucoma is detected, it has already begun doing damage. In other words, often people who have this type of glaucoma do NOT know they have it. This type of glaucoma gradually reduces the peripheral vision without other symptoms. By the time one notices it, permanent damage already has occurred. That is why everyone who is at risk for glaucoma should go for an eye check annually.
ANGLE CLOSURE GLAUCOMA – presents acutely.
Angle Closure Glaucoma: red eye, dilated pupil
This type of glaucoma is also known as acute glaucoma or narrow angle glaucoma. It is not as common as open angle glaucoma. In this type of glaucoma, the eye pressure usually rises quickly resulting in acute symptoms of eye pain, redness, photophobia (inability to tolerate light), headache and sometimes even vomiting. The patient is usually forced to seek immediate treatment from an eye doctor who has to lower the eye pressure. The eye pressure in this kind of glaucoma is usually very high and the patient is in pain.
NORMAL TENSION GLAUCOMA – presents silently.
Normal-tension glaucoma (NTG) is also known as Low Tension Glaucoma or Normal Pressure Glaucoma. Here the damage occurs to the optic nerve without the eye pressure going above the normal range. (The normal eye pressure: 10-21 mm Hg.) Researchers continue to study why the optic nerve in these individuals is susceptible to damage even with normal eye pressure readings. Many doctors however tend to believe that it is related to poor blood flow to the optic nerve. This glaucoma is also “silent” without any acute pain or symptoms. The person often ends up seeking treatment late when significant vision loss has already occurred. That is why people above 40 years of age should have their eyes checked routinely as part of their general health screening.
Dr Gill will elaborate more on 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.