Symptoms and Treatments

What is Glaucoma Symptoms?

Glaucoma is an ophthalmic disorder afflicting the major optic nerve than progressively leads to blindness if not treated. It is the leading cause of irreversible blindness in one or both eyes afflicting 6 million people worldwide

Description

The optic nerve is responsible for receiving and transmitting light impulses from the retina to the brain so we perceive vision.  Glaucoma progressively damages the optic nerve with results starting with a loss of peripheral vision can gradually losing central vision, at which point complete blindness becomes inevitable. There are various types of glaucoma.  The two main types are:

• Angle-closure glaucoma:  the drainage canals within the eyeball are physically blocked.  It can be chronic (long lasting) or acute (sudden).  Acute cases are considered emergencies as blindness can occur within hours of its onset.  Chronic cases cause vision loss without any symptom.
• Open-angle glaucoma:  the drainage remain open but cause vision loss without symptoms.

Causes and Risk Factors of Glaucoma Symptoms

Glaucoma is often associated with increased pressure or intraocular pressure in the eye which leads to optic nerve damage.  But it can also happen to people with normal intraocular pressure and the onset of the disease can be attributed to poor regulation of blood supply to the optic nerve. The optic nerve is quite delicate, one the most delicate in the human body and is the most susceptible to high pressure that hardens the eyeball

Glaucoma is easily cured when detected early. But is considered as the “sneak thief of sight because without any early warning sign or symptom,  it does not allow early detection and will gradually cause the intraocular pressure to build up to eventually damage to the optic nerve.  Anyone is carries a risk to it but the following have more predisposition to it:

• Family history of glaucoma
• Older than 45 years
• Black racial ancestry
• History of increased intraocular pressure
• History of eye injury
• Use of cortisone steroids for the eye or to treat other ailments either orally or by injection.
• High degree of myopia or nearsightedness
• Farsighted people with narrow filtering angles in their vision which predisposes them to acute close angle glaucoma

Symptoms of Glaucoma Symptoms

More than half the 3 million people in the US afflicted with Glaucoma don’t know they have the disease.  That’s because they are in the early stages when symptoms are noticeable and the loss of side or peripheral vision is hardly material.  But once it sets in, other symptoms appear often related to sudden intraocular pressure such as

• Blurred vision
• Perception of halo around lights or lighted objects
• Severe pain in one eye or both
• Headache
• Abdominal pan
• Nausea and vomiting

Normal or low pressure/tension glaucoma is rarely understood as the optic nerve is damaged despite having normal intraocular pressures. Currently, this type of glaucoma is getting significant research attention to pinpoint its cause.

Other glaucoma causes include congenital where the onset appears right after birth or up to a year thereafter and are more common boys than in girls, affecting one or both eyes.  Childhood glaucoma can be traced to congenital predisposition.

Diagnosis of Glaucoma Symptoms

This type of glaucoma is often diagnosed with repeated examinations by an ophthalmologist or eye doctor who can determine the nerve damage as well as the visual field loss.

• Tonometry determines the pressure in eyeball
• Pachimetry determines the corneal thickness
• Gonisocopy examines the filtering angle and draining ability of the eye to ascertain susceptibility to sudden closure of the angle causing acute glaucoma attacks.  It also determines if there are abnormal blood vessels blocking the drainage of the aqueous fluid of the eye.

• Ophthalmoscopy is done to examine the optic nerve at the back of the eyeball and any damage to the optic nerve can be seen right away.

• Visual Field testing maps the visual areas a patient can see to determine early or late signs of glaucoma and its extent of damage to the optic nerve. These days, computer-aided assessment is used.

Treatment of Glaucoma Symptoms

While loss of vision caused by damage to the optic nerve is irreversible, glaucoma can be controlled or managed.  Treatment involves relieving intraocular pressure on the optic nerves to prevent nerve damage or at least arrest further nerve damage anywhere along its progressive path.   The most common treatment uses eye drops to relive open angle glaucoma in the US as the first level of treatment.

Various chemical formulations such as prostaglandin analogs, andrenergic agonists, carbon anhydrase inhibitors and parasympathomimetic agents or miotics are at the disposal of ophthalmologists to prescribe.

In contrast, European ophthalmologists go for laser surgery as the first level of treatment. With either laser or conventional surgery, the objective is to drain the eyeball’s aqueous fluid to relieve pressure on the optic nerve. The options for laser surgery include:

• Laser iridotomy on either narrow or closed angle glaucoma involved drilling a hole in the iris to drain the fluid.
• Laser trabeculoplasty is done on open angle glaucoma which does not cure glaucoma but open more option for more eye drops to work.
• Laser cilioablation is reserved for people with severe forms

Conventional glaucoma surgery also aims to lower intraocular pressures and involves

• Trabeculectormy, a microsurgical procedure that is most commonly done to lower in intraocular pressure
• Aqueous shunt or tube implants are artificial draining devices surgically implanted using microscopic tubes meant to lower intraocular pressures.
• Viscocanalostomy involved surgically removing a piece of the eye wall or sclera leaving just the thin tissue membrane through which aqueous fluid can be drained.  It less invasive but is also less effective.