Glaucoma is the name of a group of sight threatening eye diseases that cause irreversible damage to the optic nerve. The optic nerve is a vital structure which transmits images collected by the eye to our brain. Progressive damage to the optic nerve can cause permanent vision loss. Optic nerve damage from glaucoma initially causes peripheral or side vision loss and so the disease may not be noticed until a late stage. By the time any visual symptoms are present, 95% of nerve function may be permanently lost.
Every eye maintains a certain amount of internal pressure, called intraocular pressure. The eye maintains this pressure by producing a fluid called aqueous. In a healthy eye the aqueous produced will drain from the eye into the bloodstream to keep the pressure from rising too much. In glaucoma, the normal drainage becomes slowed or blocked and eye pressure can rise to unsafe levels. Elevated eye pressure is a major risk factor for glaucoma although many patients with glaucoma have eye pressure measurements in the average range.
In patients with glaucoma, lowering the eye pressure can slow or stop the damage to the optic nerve.
Regular eye examinations are required to detect glaucoma.
There are many different types of glaucoma but they can be classified as either open angle glaucoma or narrow angle glaucoma.
Open angle glaucoma:
Primary open angle glaucoma is the most common form of the disease and becomes increasingly common as we get older. There are no symptoms in the early stages of open angle glaucoma. Peripheral vision is usually lost first, but if left untreated glaucoma can eventually lead to total vision loss. The best way to avoid serious vision loss is early diagnosis and treatment.
Risk factors for open-angle glaucoma include:
• Family history of the disease
• Higher than normal eye pressure
• African American heritage
• Nearsightedness (Myopia)
• Previous eye injury or surgery
Narrow angle glaucoma:
In narrow angle glaucoma the eye is usually smaller than average size and the structures within the eye are close together. This can cause the iris (colored part of the eye) to block the eyes natural drain and lead to either very rapid eye pressure elevation called acute angle closure glaucoma or slow, steady elevation of pressure called chronic angle closure glaucoma. In either case, optic nerve damage and loss of vision can result.
Acute angle closure glaucoma can result in very high pressure and is a true emergency as damage can occur rapidly.
Symptoms of narrow angle glaucoma include:
• Eye pain
• Blurred vision
• Nausea or vomiting
• Halos around lights
Risk factors for narrow angle glaucoma include:
• Advanced cataracts
• Asian heritage
Medications and Glaucoma:
Use of steroids (cortisone like medications) can cause elevated eye pressure and open angle glaucoma in some individuals. This side effect is possible with any route of administration of these medicines including oral, inhaled, nasal sprays, eye drops, injectable and topical steroids.
There are many medications that can cause narrow angle glaucoma in people predisposed to this condition. Over the counter medicines such as decongestants and antihistamines can dilate the pupil and lead to dangerously elevated eye pressure. Prescription medications for bladder incontinence, motion sickness, certain psychiatric medications, diet pills and some sulfa derived medications can cause angle closure glaucoma. Always check with your ophthalmologist before starting new medications if you have glaucoma.
Treatments for glaucoma:
There are a wide range of treatments for glaucoma including medications, laser procedures and traditional surgery. The treatment for an individual is chosen based upon the type of glaucoma and the patient’s individual needs.
For open angle glaucoma, prescription eye drops are usually employed first to lower the eye pressure. Some patients who do not respond adequately to drops may require laser trabeculoplasty or a glaucoma operation called a filtering surgery to control the disease.
Patients with narrow angle glaucoma may require laser iridotomy (a very small hole in the iris) as initial therapy for the disease. Treatment for narrow angle glaucoma is highly individualized and may require eye drops and occasionally surgery as well.
Laser for open angle glaucoma:
Laser surgery is a common treatment option for glaucoma. For open-angle glaucoma, laser trabeculoplasty may be needed if eye drops alone do not control the pressure. This is a painless laser procedure, performed in the office, which uses laser light to improve the eye’s natural drain.
Other glaucoma treatment options involve surgery. A common surgery for open and narrow angle glaucoma is called a trabeculectomy or glaucoma filter. During this surgery, the doctor creates a small flap in the sclera (white part of the eye) and a very tiny hole beneath this flap. This allows fluid to drain into a small reservoir called a bleb on the surface of the eye.
Dr. Joshua Gould and Dr. Devang Bhoiwala are board certified ophthalmologists and fellowship trained glaucoma specialists. They use the most up to date diagnostic and therapeutic modalities in the early detection and treatment of glaucoma.
The diagnostic tools and treatments available for glaucoma are more effective than ever before. Your vision is irreplaceable so please do not hesitate to call for an appointment today.