Glaucoma is relatively common & serious eye disease, if not treated timely. In this disease, optic nerve of the eye is progressively damaged and can lead to irreversible blindness if not timely managed.
This damage can occur due to high intraocular pressure (IOP) and/or compromised blood supply to optic nerve.
Normal intraocular pressure is up to 21 mm Hg.
Increased intraocular pressure (IOP), larger size of cup of optic discor asymmetry in size of cup of two eyes, family history of glaucoma and myopia are important risk factors of glaucoma. With progression of disease, cupping of optic disc increases further.
Type of Glaucoma:
On the basic of angle of anterior chamber of eye, Glaucoma is divided into two types:
Open angle glaucoma:In this subtype, angle is open like in any normal person.
Narrow or Closed angle glaucoma:In this subtype, angle in closed or narrow.
Sign /Symptoms:-here may be no sign /symptoms in open angle glaucoma. While headach, pain in eyes, redness of eyes, color halos & blurring of vision occurs in angle closure glaucoma patient.
Medical: Various eye drops are used to lower the IOP
Laser: It has more important role in closed angle glaucoma
Surgical: Surgery is performed to reduce the IOP
Purpose of Treatment:
Damage done by glaucoma is irreversible i.e. it cannot be reversed by treatment. Purpose of treatment is to stop further progression of glaucoma. Sometimes in spite of treatment, glaucoma progresses further.
Tests for Glaucoma:
Diurnal variation of IOP
Gonioscopy:This gives the information regarding the angle of the eye (Open or Closed)
Visual Fields:This is a subjective test for evaluation of damage to the eye due to glaucoma. It analyzes the visual field of the eye.
OCT:It is done for objective evaluation of retinal nerve fibre layer, and optic disc which are affected (damaged) in glaucoma. RNFL thickness decreases & cupping of optic disc increase with progression of disease.
Fundus Photograph :-it is done to evaluate changes in cupping with time.
Pachymetry :-it is measurement of central corneal thickness done to calculate true IOP.
Important to remember that visual acuity of eye i.e. capacity to see things clearly is usually affected very late in the course of illness so patient may not feel any illness in the eye in spite of advanced and progressive glaucoma (SILENT KILLER).