Glaucoma

What is Glaucoma? The human eye produces a fluid which provides nutrition to the inside structures of the eye. This fluid keeps moving out of the eye through channels in the angle of the eye. In a normal eye, the amount of fluid produced balances out the amount of fluid flowing out of the eye. That keeps the pressure inside the eye (intra ocular pressure) stable. With advancing age, or due to other reasons these channels get partially blocked and the imbalance in the fluid dynamics results.

This results in raised pressure within the eye. The raised pressure then starts damaging the Optic nerve. Optic nerve carries the visual signals from the eye to brain thus making vision possible. The damage thus caused to the Optic nerve leading to a decrease in the field of vision and sight is called GLAUCOMA.


GLAUCOMA IS THE SECOND LEADING CAUSE OF BLINDNESS IN THE WORLD OVER AND THIRD MOST COMMON CAUSE OF BLINDNESS IN INDIA.

Types of Glaucoma
There are three major categories of Glaucoma. These are:

• Primary open-angle or chronic glaucoma : This is the most common form of glaucoma. Damage to the vision in this type of glaucoma is gradual and generally painless. The affected person normally remains completely unaware of the disease until the optic nerve is already damaged badly which leads to decrease in the visual fields.
• Closed angle or acute glaucoma : In this type of glaucoma, the intra ocular pressure increases very rapidly due to a sudden and severe block of fluid drainage within the eye. Significant symptoms indicating the presence of acute glaucoma appear suddenly. This condition has to be treated immediately by an ophthalmologist otherwise blindness may occur.
• Other types of glaucoma are Congenital glaucoma, Pigmentary glaucoma and Secondary glaucoma.
• All types of glaucoma are characterized by three common features.
• Increased intra ocular pressure: It has been a cardinal sign of glaucoma. This is measured by tonometry (Goldmann Application Tonometer, Schlitz tormenter etc.)
  Increased IOP does not always requires treatment and normal IOP does not always rules out glaucoma.
• Cupping or Atrophy of the Optic Nerve: This is the drying up of the optic nerve as a consequence to the damage suffered because of high pressure in the eye. This is assessed by examination of the Fundus of the eyes.
• Visual Field Defects: This is basically the presence of missing areas in the field of sight even though the person may be seeing well otherwise. This condition is measured on an instrument called the Perimeter.
  
  

  The symptoms of Glaucoma
• Glaucoma in early stages generally does not show any noticeable symptoms. It is possible that a person suffering from chronic glaucoma to be completely unaware of the disease. Chronic (open angle) glaucoma generally progresses too slowly to get noticed. Some common symptoms of chronic glaucoma could be:
• Inability to adjust the eyes to darkened rooms such as theaters.
• Subtle problems in ability to see in night.
• Frequent changes (sooner than 6 months) in eyeglass (reading) prescription.
• Gradual loss of peripheral vision.
  
  In the case of Acute Glaucoma (Angle Closure) which results from rapid increase in the Intra ocular pressure, there could be severe symptoms. Common symptoms suggesting the presence of acute glaucoma could be:
• Blurred vision.
• Severe eye pain, facial pain.
• Seeing rainbow colored halos around lights in the evenings.
• Headaches.
• Redness in the eye with sudden loss of vision.
• Nausea and vomiting.
  
  The high-risk groups who can get glaucoma
• People belonging to families with a history of glaucoma.
• People suffering from diabetes.
• People having high minus or plus numbered glasses.
• Everybody over forty years of age.
• People suffering from hypertension.
• Anybody who has undergone any kind of eye surgery.
• People with thyroid gland related ailments.
• People with over mature cataracts.
• People with any injury to the eye.
• People with a history of prolonged use of steroid eye drops.
  
  Is Glaucoma curable?
  Glaucoma cannot be cured. But it can be controlled and further damage to the optic nerve can be slowed down or halted. This control can only be sustained through very disciplined and regular treatment as advised by the ophthalmologist. It is life long process.
  
  What are the treatment options for Glaucoma?
  (a) Medication (Eye drops) The chronic open angle variety of glaucoma which has not progressed too far can be controlled by the use of eye drops alone. These drops may have to be put 2-4 times a day. In case of higher intra ocular pressure, the patient may have to use more than one type of eye drops.
  
  (b) Laser treatment
  Laser treatment is a must for acute type and angle closure variety of glaucoma. Laser treatment is also done to control pressure in open angle type glaucoma. Now a new technique called ELT or Excimer Laser Trabeculotomy is also available which helps in lowering the pressure with the help of a small surgery.
  
  (c) Surgery
  In those cases where eye drops and laser treatment do not prove sufficient to control the pressure, surgery is done to create an alternate pathway for the fluid to drain out.
  
  Must remember facts about Glaucoma.
  Glaucoma is a symptom complex and as such there is no prevention for development of glaucoma. It’s early detection and prompt treatment can prevent deterioration of vision and blindness.
  
  Here are few tips to be remembered:
• Immediately get in touch with an eye specialist, if you experience any of the following:
• Severe eye pain.
• Sudden loss of vision.
• Nausea and/or vomiting.
• Poor night vision.
• Persistent redness of the eye.
• Frequent changes in reading glasses prescription.
• If you are over forty and/or have a family history of glaucoma, go for regular tonometry (intraocular pressure check-up).
• There is no prevention of the development of glaucoma.
• Sometimes the symptoms of glaucoma are simply not noticeable.
• Glaucoma can silently snatch away your vision.
• Timely detection of glaucoma is a must.
  
  Timely treatment of glaucoma may prevent further loss of vision and blindness.
  
  REMEMBER !
  Irregularity in the treatment schedule which is a lifelong process may snatch away your ability to see and appreciate this colorful and wonderful world despite your ophthalmologists best efforts.