What is Glaucoma?
Glaucoma is slowly progressive optic neuropathy (progressive damage to the nerve of the eye which connects the eye to the brain) resulting in progressive loss of vision. Intraocular pressure (IOP) is the only modifiable risk factor in case of glaucoma.
Types of Glaucoma:
There are several types of Glaucoma. The two major types include:
1. Primary Open Angle Glaucoma
2. Primary Angle Closure Glaucoma
The above classification is based upon the angle anatomy. The space between the front transparent part called as the cornea and the brown color structure in front of lens called iris forms the angle of the eye. In glaucoma, if this space remains intact it is called as Open Angle Glaucoma. However, if there is a contact between cornea and iris, in which case this space is obliterated, it is called as Angle-closure Glaucoma. Unlike the western world, in the Indian population, both types of glaucoma are equally prevalent.
Primary Open Angle Glaucoma
Primary Open Angle Glaucoma presents with high intraocular pressure. In some cases, the optic neuropathy can be produced in presence of normal intraocular pressure as well. This condition is termed as Normal Tension Glaucoma. This type of glaucoma is usually asymptomatic and diagnosed incidentally while a routine eye check-up is being done.
Primary Angle Closure Glaucoma:
This type of glaucoma can present with high intraocular pressure or normal intraocular pressure. Acute angle Closure Glaucoma is the subtype of Primary Angle Closure Glaucoma which presents with the sudden rise of intraocular pressure leading to eye pain, headache, nausea, and vomiting. This is an emergency which needs immediate intervention by the eye specialist and control of eye pressure.
Primary Open Angle Glaucoma is treated with eye drops which are aimed at reducing intraocular pressure. Here once the target pressure is determined based on the pre-existing eye pressure and the extent of optic nerve damage, different eye drops are initiated to achieve that. Constant monitoring of eye pressure and field of vision is done to ensure that eye pressure stays under check and the field of vision is not worsening any further.
-The first mode of treatment in case of Primary Angle Closure Glaucoma is Laser Iridotomy.
The laser procedure is done to create a hole in the iris and to open the space between cornea and iris. After the laser treatment, the patients are given drops to lower intraocular pressure based on the amount of pre-existing optic nerve damage and the eye pressure. Even in angle closure glaucoma patient is monitored and evaluated at regular intervals to ensure that eye pressure is controlled, and the field of vision is maintained.
Glaucoma is a disease of the lifetime. It requires a commitment from the patient and the glaucoma specialist. Patients compliance for treatment, regular follow-ups is crucial to prevent progression and protect the eye from blindness. Eye doctors should make sure that they educate their patients well against the possible consequences of not complying with instructions and the treatment.