What is Glaucoma?
Permanent damage on neural layer providing vision occurs in Glaucoma which is one of the most common reasons for blindness. The most important risk factor is high intraocular pressure. However in some glaucoma patients, eye pressure may be at normal levels. Therefore, assessing only the intraocular pressure is not correct to make or exclude the diagnose. In most of the patients, disease follows an insidious pathway, it reduces the visual acuity without causing complaints like pain or redness. Therefore, an early diagnosis is very important. Computer-assisted visual field tests, analysis of head of the optic nerve and its fibers are the main methods used for diagnosis and following up the diagnosed patients.
As the most common type of glaucoma, it occurs in advanced ages (at the age of 50). The pressure of the eye gets high due to inadequate drainage of the intraocular fluid and it damages the optic nerve. Eye pressure is normally lower than 21mm Hg in normal people. It is generally high in patients who are diagnosed with glaucoma. However optic nerve may be damaged while the pressure is at normal range in some people. People who have high intraocular pressure but no evidence of damage caused by glaucoma are assessed as “ocular hypertensive”. It is insidious. Patients do not recognize the vision loss at the early stages. Therefore, an eye examination must be performed at the age of 40 and afterward, it must be performed once a year as of fifties. As the disease progresses, wide fields of vision loss occur. Blindness is caused by the entirely damaged optic nerve.
Angle Closure Glaucoma
It is a rare type of glaucoma. It generally occurs in smaller eyes having hypermetropia when the iris closes the drainage angle. Intraocular pressure instantly increases around the levels of 40-45mm Hg.
This situation is quite painful. It is accompanied by nausea and vomiting, and vision becomes blurred.
It must be treated immediately, it may cause permanent blindness. In some patients, angle-closure occurs gradually in years.