All you need to know about Glaucoma

Glaucoma is a condition of the eye wherein a build up of fluid pressure inside the eye causes damage to the optic nerve present in the eye. A small void is present in front of the human eye. This void is known as the anterior chamber. Clear liquid known as aqueous humor, useful for the cleaning and nourishment of tissues, flows in and out of this anterior chamber. In a person suffering from Glaucoma, this fluid does not drain out from the eye as frequently and quickly as it should. This leads to a build up in the fluid pressure inside the eye, causing damage to the optic nerve.



Unless this fluid pressure is released, decreased and brought down to normal levels, a person suffering from Glaucoma stands the risk of vision loss owing to excessive damage to the optic nerve inside the eye. Glaucoma usually affects both eyes but with varying intensities.



Types of Glaucoma


There are mainly two types of the glaucoma infection. These include the following:

  • Primary open-angle glaucoma or Chronic glaucoma 

            The primary open-angle glaucoma is a condition that progresses very slowly. A person affected by this condition may not notice any symptoms in the initial stages – even slight vision loss might go unnoticed. Primary open-angle glaucoma poses a major risk of vision loss mainly due to this reason as people do not notice symptoms and opt for treatment until it is too late and permanent damage has already occurred.



  • Closed-angle Glaucoma 

Closed-angle Glaucoma is another type of glaucoma observed more commonly in patients. The condition occurs suddenly and the patient usually experiences pain in the eye and rapid vision loss.


Usually, patients seek immediate medical aid owing to the immense pain and discomfort caused by this condition, thereby limiting further and permanent damage to the eye.



Other minor categories of glaucoma include the following:


  • Pigmentary glaucoma : pigmentary glaucoma is a type of open-angle glaucoma that usually develops during early or middle adulthood. The pigment cells that originate at the iris get dispersed in the eye, upsetting the normal flow of fluids inside the eye. This causes an increase in the fluid pressure in the eye, thereby leading to glaucoma.
  • Low-tension glaucoma : low-tension glaucoma is a rare form of glaucoma, the causes and conditions of which are not clear top experts as yet. In this condition, there is significant damage to the optic nerve, although the pressure of fluids on the optic nerve is normal. It is widely believed that this damage is caused due to reduced blood supply to the optic nerve. 



Causes of Glaucoma


  • Conditions such as diabetes, cataract and tumors have been identified as likely causes for secondary glaucoma
  • Other risk factors for the condition include the following:

◦           Old age

◦           Ethnic background – african americans, those of Hispanic descent and East Asians have been identified as those falling in the high risk ethnic groups.

◦           Eye surgery

◦           Myopia

◦           Hyperthyroidism

◦           Eye injuries



Symptoms of glaucoma



The symptoms of open-angle glaucoma include the following:



  • Loss of peripheral vision, almost always affecting both eyes.
  • Tunnel vision is experienced by patients in advanced stages of primary open-angle glaucoma.



The symptoms of closed-angle glaucoma include the following:



  • Red eyes
  • Blurred vision
  • Usually severe eye pain
  • Patients suffering from closed-angle glaucoma usually notice extra glow-like halos around lights.
  • Nausea and vomiting might accompany eye pain
  • Unexpected and sudden problems in vision, especially when the lighting is poor.



Diagnosis of Glaucoma



Your ophthalmologist uses eye drops in order to dilate your pupils. Then he/she tests your vision by making use of standardised tests and examines your eye with a lens. Next, your optic nerve is checked in order to look for any damage that might point to the presence of glaucoma in your eyes. Photographs of your eye may be taken in order to track the progress of your disease with time.



A tonometry diagnostic test may also be performed by your ophthalmologist in order to check your eye pressure. The tonometry test performed by your ophthalmologist may be any one of the following:



  • Electronic indentation tonometry : in the electronic tonometry test, your ophthalmologist places the round tip of a pen-like tool directly on the cornea of your eye. The intraocular pressure is then read off a small computer panel attached to the tool. 
  • Goldmann applanation tonometry : the Goldmann applanation tonometry procedure uses a small probe that is flattened onto your cornea in order to measure your intraocular pressure. A tiny microscope known as a slit lamp is also used in order to look into your eye.
  • Pneumotonometry : pneumotonometry or air-puff tonometry uses a puff of air to flatten your cornea, without making any physical contact or direct contact with your cornea. 



Treatment of Glaucoma


The treatments for Glaucoma prescribed your ophthalmologist vary according to the intensity of your condition. The different treatments that might be prescribed your ophthalmologist include the following:



  • Eye drops : eye drops are usually prescribed by an ophthalmologist when the glaucoma is in the initial stages and can be treated without intravenous medical intervention. Eye drops usually help in the treatment of glaucoma by either reducing the formation of fluid in the eye or by increasing the outflow of fluid, thereby releasing the pressure on the optic nerve, thus helping in the treatment of glaucoma. The administration of eye drops may cause some side effects such as singing, irritated eyes, blurred vision and redness in some patients. 


  • Laser surgery : usually prescribed to people with open-angle glaucoma, laser surgery helps increase the outflow of fluid from the eye.

            •           Microsurgery :  in this procedure, a new channel is created in order to drain the excess fluid and release fluid pressure on the optic nerve.