Glaucoma or ‘Kala Motia’ is a condition wherein an increased intraocular pressure damages the optic nerve, thereby affecting vision. In the normal eye, the rate of production of aqueous (the fluid that nourishes the front part of the eye) matches the rate of its drainage, thereby maintaining optimal pressure inside the eye. However, with age, disease, trauma or other factors, the channels carrying this fluid may get blocked, increasing the pressure inside the eye.
This increased pressure damages the optic nerve, which is the conduit of visual messages to the brain. Working silently, glaucoma damages the outer or peripheral vision first while maintaining the central vision, says Dr Mahipal S. Sachdev, chairman, Centre for Sight.
Glaucoma is called the silent thief of sight because there may be no symptoms in the early stages of the disease. This condition threatens vision and is known to gradually steal sight without warning. By the time glaucoma is detected, the patient has already suffered extensive peripheral vision damage which can no longer be restored.
It is the leading cause of blindness in the United States, and a study presented at the World Ophthalmological Congress in 2008 projected India as the next glaucoma capital. Almost 68 per cent Indians run the risk of developing the disease, and nearly 1.2 lakh Indians go blind every year due to this disease.
Below, Dr Sachdev shares the risk factors, symptoms and ways to manage the condition.
You are at risk, if:
*You are 45 years of age or above
*You have a family history of glaucoma
*You have health problems such as diabetes, hypertension or thyroid disease
*You suffer from myopia or nearsightedness
*You have had ocular trauma or intra ocular surgery in the past
Types of glaucoma:
There are two major types of glaucoma
*Chronic or Primary Open-Angle Glaucoma (POAG): The chronic open angle form of glaucoma is the most common form. Damage to vision is gradual and generally painless.
*Closed or Acute Angle-Closure Glaucoma : In the closed or acute form, the intraocular pressure increases rapidly due to a sudden and severe block of fluid drainage within the eye. Significant symptoms indicating the presence of acute glaucoma appear immediately. This condition has to be treated quickly by an ophthalmologist otherwise blindness may occur.
*Inability to adjust the eyes to darkened rooms, such as theaters
*Poor night vision
*Frequent changes in eyeglass prescription
*Gradual loss of peripheral vision
*Feeling of a blind area in the eye
*Seeing rainbow coloured halos around lights
*Severe eye pain, facial pain, nausea and vomiting
Glaucoma cannot be cured, but it can be controlled so that further damage to the optic nerve can be slowed down or halted. This can only be done through disciplined and regular treatment. The treatment of glaucoma is life-long.
Management of Glaucoma
Glaucoma treatment may include medical management, surgical management or management by lasers. Medical management is using eye drops. Surgical management includes a procedure where an opening is made to create a new drainage pathway for the fluid to leave the eye easily. Management by lasers includes procedures such as trabeculoplasty, in which a laser is used to pull open the trabecular meshwork drainage area; iridotomy, in which a tiny hole is made in the iris, allowing the fluid to flow more freely; and cyclophotocoagulation, in which a laser beam treats areas of the ciliary body, reducing the production of fluid.
Ways to treat
There is no proven way to prevent glaucoma. Frequent monitoring, regular checkups can help detect the disease in its early stages.
*Take your medicines exactly as prescribed. Use the right drop in the correct eye at the right time in the right way.
*Try to schedule the time for taking medication around daily routines such as waking, mealtimes and bedtime.
*Drinking large quantities of water on empty stomach early morning should be stopped. This habit temporarily increases the Intra Ocular pressure.