Glaucoma

Glaucoma is a disease of the eye where the patient develops blind spots in the visual field. This usually starts with the peripheral vision. Glaucoma is a leading cause for blindness worldwide. Early detection is vital in treating glaucoma. Glaucoma is noticed more among Asians and African-Americans. It usually affects persons who are above 60 years. Glaucoma tends to be hereditary. An injury to the eye can result in glaucoma in later years. Other factors such as hypertension, diabetes or high myopia increase the risk of glaucoma.

Intra ocular pressure(IOP) is a primary cause for glaucoma. Primary open-angle glaucoma usually does not exhibit any symptoms and continues to damage the optic nerve. Acute angle-closure glaucoma is a condition where the disease develops rapidly subsequent to rapid rise in eye pressure. Here the patient may suffer severe eye pain and blurred vision. This might be accompanied by nausea and vomiting. Here the drainage angle between the cornea and iris gets blocked. This can happen due to normal aging process or farsightedness. Secondary glaucoma is a condition where the glaucoma develops due to increased eye pressure caused by some other disease.

Tonometry is a test for intraocular pressure. The ophthalmologist will check for damage to optic nerve and check how much of your visual field has been affected. These tests aid in detecting the amount of damage caused by glaucoma and progression of the disease.

Glaucoma can only be controlled, not cured. Eye drops, oral medications and surgical procedures can slow down the damage caused by the disease. Glaucoma Medications include beta blockers, prostaglandin analogs, cholinesterase inhibitor and adrenergic. Oral medications may also be prescribed to reduce eye pressure. But these medications may bring about side effects. Laser surgery or trabeculoplasty is often used to tackle open-angle glaucoma. This surgical procedure aims to drain the aqueous humor from the eye and reduce pressure. It does not require hospitalization.

Iridotomy

Iridotomy involves focussed use of Laser on the iris of the eye for patients suffering from glaucoma. Laser iridotomy is used to prevent subacute closed-angle glaucoma and acute closed angle glaucoma. Iridotomy can be done as an outpatient procedure. First the eye is numbed and a small opening is made on the iris so as to reduce the pressure building within the eyeball. The patient wont go through any pain but some localized heat or pinching sensation. Complications that can arise with iridotomy are bleeding in the iris, blurred vision for a brief period and in rare cases loss of vision.

Tonometry

Tonometry test is a diagnostic test to measure the intraoccular pressure (IOP). When the tonometry test measures the pressure inside the eye, it can help in detecting glaucoma. Ensure that you take off your contact lenses. Do not wear tight clothing around the neck as it can lead to increased pressure inside the eye. Do not smoke a few hours prior to the tonometry test. The tonometry test is also conducted in cases of head or eye surgery and hyphema.

When the pressure builds up within the eye due to improper drainage, it can cause permanent damage to the ooptic nerve. Tonometry is done as part of routine eye examination to check for glaucoma. Anesthetic eye drops are used to numb the eye before using the tonometer. In the application method of testing intraoccular pressure, a paper stained with Fluorescein is placed to the side of the eye thereby staining the front of the eye. The tonometer is then brought close to the cornea for testing. Here the intraoccular pressure is measured by the amount of weight that is needed to flatten the cornea. This type of tonometry test can also be conducted with a pencil-like instrument, which will give instant digital measurement. The air puff method of conducting tonometry is a non-contact one where a puff of air is blown at your eye and change in the light reflected from the cornea is measured to arrive at the intraoccular pressure. This method is preferred for children and persons who have undergone LASIK surgery.