World Glaucoma Week – 10 – 16 Mar 24
By: Dr. Mahipal S Sachdev
Glaucoma is a serious disorder that encompasses a group of eye disease that leads to progressive damage to the optic nerve, which transmits electrical signals from the eye to the brain. This problem usually occurs when a fluid builds up in the front part of the eye. This extra fluid increases the pressure in eye, which damages the optic nerve. People above the age of 60 years face the complications of Glaucoma which is a leading cause of blindness.
The early stages of Glaucoma have no symptoms and by the time patient start notice problems with the sight, this disease progresses so much that irreversible vision loss has already occurred and additional loss is difficult to stop. But Glaucoma can be controlled and prevented with early treatment.
Glaucoma can induce without noticeable symptoms. An ophthalmologist will diagnose this disease by doing a comprehensive medical eye examination. The best way to protect your sight from glaucoma is to have regular eye examination tests to assess your eye pressure, optic nerve, cornea and other potential problems.
The following components of tests that help early detection are as follows:
Medical History, Medications you are taking, Questions about diabetes, high blood pressure, smoking and sun exposure.
Vision History: Your last eye examination, present tests and recent changes in your vision.
Eye disease in your family, Any previous treatments and surgeries.
Vision acuity test to determine your sharpness and clarity of your sight. This test is done to determine if your vision can be improved by using glasses or lenses. It also helps the doctor to determine the risk of glaucoma in your eyes.
Basic Visual Filed testing is done to determine how much side vision and how much surrounding area patient can see.
An anterior segment of eye includes the cornea, pupil, iris, lens and aqueous drainage structure is examined through microscope. Special lens which allows the doctor to see inside the eye to examine the retina and optic nerve is called dilated eye examination.
The test through which the fluid pressure is measured inside the eye is referred as tonometry test or IOP.
The Warning Signs
The following signs, indicates that you need a thorough examination by an eye doctor:
Change in the color of iris, Double vision, The centre of viewing has a dark spot, Feeling unusual in dark rooms, Difficulty in focusing on near objects, Squinting due to unusual sensitivity to light, Swollen lids, Pain in eyes, Watery eyes, Itching and burning in eyes, Seeing ghost like images in dark.
Who is at Risk?
The risk factors that determine for developing the disease include:
Elevated eye pressure, Family history, Age, Past injuries to eye, Use of steroid, Thin cornea, Severe anemia.
How is Glaucoma Detected?
If ophthalmologist suspects that you may have glaucoma ,then the patient has to undergo additional tests that helps to make sure the certainty of the disease.
Pachymetry
An instrument that emits an ultrasonic wave to measure the thickness of the cornea is used in this test. A painless ultrasound wave emits from the probe and doctor numb the surface of eye to measure the corneal thickness.
Perimetry
This test draws the map of patients virtual field and show where he has lost the vision especially the peripheral vision. The doctor can easily see the areas of vision damaged and the areas that are going to affect.
Gonioscopy
The doctor cant see directly the damaged angle by looking directly into the eye. So this test gives access to check the drainage canal that is formed between cornea and iris. The drainage canal is located at the corner of cornea. It is very important to examine the drainage canal to ensure they are working properly.
Angle or the drainage canal is viewed through lens with mirror, doctor numbs the surface of eye and then places this lens.
The reports from these tests provide an indication of the effectiveness of the treatment being used and whether further treatments may be necessary. All the tests are not necessary for every person. The objective is just to determine if the glaucoma has stated affecting or damaged eye over time.
The writer is Chairman & Founder, Centre for Sight group of Eye Hospitals
