Glaucoma is a disease often called ???The Silent Thief of Vision???. This occurs when the pressure inside the eye increases causing damage to the Optic nerve leading to permanent and irreversible loss of vision. It requires early diagnosis and treatment to prevent loss of vision. Generally both eyes are involved, and it runs in family.
The pressure as well as the nourishment of the eye is maintained by secretion of Aqueous humor. This fluid flows across front part of the eye before draining out of the eye. In people with glaucoma, this drainage path is partially or completely blocked causing the pressure to build up. This damages the optic nerve leading to slow vision loss.
In early stages the vision loss occurs only on the side vision, keeping the front vision good till last stages. The vision loss caused by glaucoma is permanent and cannot be rectified.
Pressure in the eye can also go up due to
- Too much fluid production
- Eye diseases like cataract, Iritis etc
- Use of steroid containing drops, tablets
Risk factors for Glaucoma
- Age (Over 40 years)
- Near-sightedness (Myopia)
- A family history of glaucoma
- Past injuries to the eyes
- A history of severe anemia or shock
- Diabetes/ Hypertension
Types of Glaucoma
Open-angle glaucoma is a common form of glaucoma. Also In this type, the aqueous drainage is clogged at the trabecular meshwork. Usually this type is asymptomatic.
Acute angle-closure glaucoma Here the blockage is due to narrow angles between cornea & the iris. There is a sudden increase of intraocular pressure, which may cause:
- Intermittent blurring
- Severe eye pain & redness
- Headache & brow ache
- Rainbows like haloes around lights
- Nausea and vomiting
Glaucoma Childhood: Developmental or congenital glaucoma is caused by an abnormality that is present since birth. Symptoms are large eyes in childhood, unable to see ordinary light, misty appearance of the eyes and jerky eye movements.
Signs & Symptoms of Glaucoma
- Usually no symptoms until late
- A routine eye check up is often the first time Glaucoma is detected.
- Hence it is recommended that everyone above the age of 40 yrs undergoes a glaucoma check up
Normal Optic Disc
Peripheral Vision loss
Diagnostics and Treatment Facilities:
Amrit Hospial is equipped with the latest technology to identify glaucoma at an early stage to prevent loss of vision:
- Topcon Not Contact Tonometry (Japan): to measure the pressure inside the eye
- Hagg Streit Applanation Tonometry (Swiss): Gold standard in measuring the eye pressure
- Gonioscopy 2 mirror: is essential to see the angle of anterior chamber, and to visualize abnormalities in drainage path.
- Alcon Pachymetry (USA): Is to measure the thickness of the cornea, and is a guide to calculate the appropriate target intraocular pressure
- Zeiss visual field examination: Is the gold standard for analyzing the visual fields to see the extent of loss of side vision. The efficacy of control with the eye drops is also assessed by repeating the visual fields yearly.
Eye drops is the first line of treatment and needs to be used lifelong. Depending on the severity, it may have to be used once or several times a day, sometimes in combinations.
Nd YAG iridotomy : In angle-closure glaucoma, the laser is used to create a hole in the iris to improve the flow of aqueous and gives adequate & permanent results. This is to be done generally in both the eyes.
When a surgery is needed to control clinically non responsive glaucoma, or when it needs to be done along with Phaco IOL surgery, a new drainage channel is created through which the aqueous fluid can leave the eye. This lowers the IOP and effectively controls glaucoma in most of the patients.