Glaucoma Treatment Guidelines

Glaucoma Treatment Guidelines

OVERVIEW

What is glaucoma

Glaucoma is one of the blinding diseases of the eye. Unlike other blinding disease of the eye such as infections and ulcers of cornea, retinal diseases, age-related problems, diabetic and hypertensive retinopathy, with timely recognition and management, glaucoma can be slowed down so that a person will not become blind in his lifetime. however, the vision that is lost can be reversed with any treatment strategy.

Glaucoma is the disease of the optic nerve, affecting the visual field in which certain risk factors play an important role like intraocular pressure, age, myopia, hypertension, and racial factors.

Glaucoma may start without any symptoms, some patients may feel pain around the eyes, haloes in the room, deterioration in the visual field, watering from eyes, and redness in the eyes.

Glaucoma treatment starts with medications in the early stages. Compliance is the key factor in the regulation of glaucoma treatment. certain other procedures like laser trabeculectomy and glaucoma surgery e.g., trabeculectomy can be performed if the disease is in an advanced stage or the patient has a compliance problem oris having multiple drug therapy.

Symptoms of Glaucoma:

What are the warning signs and symptoms of glaucoma

These includes reduced

• Visual acuity reduction
• Reduction in the peripheral visual field
• Eye ache or headache
• Watering, redness of eye
• Haloes and smoke in the room.
• Some types of glaucoma may go unnoticed by the patient such as chronic glaucoma and normal tension glaucoma

Pathophysiology of glaucoma

Certain factors are postulated to cause glaucoma. These includes

• Direct mechanical damage:
• The retinal nerve fibers pasting through lamina cribrosa may receive direct mechanical damage.
• Ischemic damage:
• Ischemic damage is caused due to compression of blood vessels supplying the optic nerve.
• Common pathway:
• Both mechanisms can result in a reduction of axoplasmic flow, interference with the delivery of nutrients or removal of metabolic products, oxidative injury, or immune-mediated damage.

Glaucoma Risk Factors:

Who might get glaucoma

These includes

• Raised intraocular pressure
• Increased age
• Race factor, African of Hispanic descent
• Diabetes and hypertension
• First-degree relative with glaucoma
• Use of contraceptive pills
• Thin corneal thickness
• Raynaud’s disease or migraine
• Reduced ocular perfusion pressure

Diagnosis and Tests:

How is glaucoma diagnosed

Glaucoma is a silent blinding disease, in the early stages you might not know that you are actually having glaucoma, however keeping in mind the risk factors, a regular ophthalmic checkup will help to diagnose it and start treatment well on time. The ophthalmologist will perform the following test to diagnose glaucoma

• Visual equity.
• Visual functions include RAPD and color vision.
• Slit-lamp examination of the cornea, lens, anterior chamber depth measurement, and iris assessment.
• Gonioscopy for the assessment of open or closed angles
• Tonometry for the measurement of intraocular pressure.
• Optic disc and fundus examination.

Types of Glaucoma:

What are the types of glaucoma

The types of glaucoma can be widely divided into open angle glaucoma and angle closure glaucoma.

• Open angle glaucoma: It is one the most common cause of glaucoma. In this type of glaucoma there is no iridotrabecular contact, hence the angels are open. The main pathology lies at deposition of tiny particles in the draining canals of the eye and leading to building up of pressure. The particles may include pigment, lens particles, pseudoexfoliation material etc.
• Angle closure glaucoma:In angle closure glaucoma the angle between the iris and trabecular meshwork is occluded. This may be caused due to pupillary block or due to posterior anterior synechaes. This type of glaucoma can present with acute symptoms of sever pain, tearing, watering, red eyes and can leave certain marks of acute damages such as corneal edema, infarction in epithelium of lens and optic disc changes.
• Normal tension glaucoma: in normal tension glaucoma, the intraocular pressure is under normal limits. There is decline in the visual field and optic disc damage like other types of glaucoma.

Treatment of glaucoma

There is no permanent or reversible treatment of glaucoma, however, the health professional will make an effort to slow down the damaging process.

Treatment of glaucoma includes

Medical treatment

Glaucoma Medicines:

The initial management of glaucoma includes topical and oral medications. The types of medication depend on your health and other co-morbidities.

Eye drops for glaucoma

Latanoprost and other prostaglandins for example tafluprost, travoprost, and bimatoprost are considered the first-line topical medications.

Beta-blockers such as timolol, levobunolol, and carteolol are contraindicated in heart diseases and asthmatic patients.

Alpha 2 agonists include brimonidine and apraclonidine. It is contraindicated in patients under the age of 9 years. The major complication is CNS depression.

Carbonic anhydrase inhibitors are available in oral and topical form. These medications are used in cases where extensive lowering of pressure is required. However, CAI is contraindicated in patients with renal stones and renal failure.

Mannitol and glycerol are used in an acute attack of glaucoma. Mannitol is administered via intravenous route and glycerol is given orally.

Laser procedures:

Laser is used in the treatment of glaucoma keeping in mind its indications and benefits. Two types of LASERs are used for glaucoma treatment, Argon, and Nd: YAG. The indications for lasers include primary glaucoma, multiple drug therapy, primary congenital glaucoma, and unresponsive to medical treatment.

How long will I need to use glaucoma eye drops?

If the intraocular pressure and the ongoing damage to the optic nerve is under control, the patient is advised to use glaucoma drops for life long.

Surgeries and Other Therapies:

Surgical procedures:

When LASERs and medical treatment can’t maintain the intraocular pressure and slow down the ongoing damage, then surgical procedures are performed. These include trabeculectomy and glaucoma valve implantation.

In trabeculectomy, a fistula is created under the cover of the sclera for the passage of aqueous humor from the anterior chamber into the subtenon space.

The novel procedure is the implantation of a glaucoma valve. In this procedure, a passage is made between the anterior chamber and sub-tenon space with the help of a valve. Indication for glaucoma valve surgery includes eyes with conjunctival scarring, uncontrolled glaucoma, neovascular glaucoma, or when the conventional trabeculectomy has failed.

In non-penetrating glaucoma surgery, the anterior chamber is not entered and the trabecular meshwork is preserved. The surgery is technically challenging and involves meticulous dissection of the scleral flap.

Cycloablation procedure is the treatment option for blind and painful eye, where there are least chances of vision restoration.

Does glaucoma affect both eyes

It depends upon the cause of glaucoma. Normal-tension or primary open-angle glaucoma is usually in both eyes, while angle-closure glaucoma can occur in one only. If the cause of neovascular glaucoma is a tumor, only one eye will be involved.

Glaucoma medication is used lifelong or not

Yes, the glaucoma medications are used for life long even if the patient experience no symptoms and if the intraocular pressure is under normal range.

When should I call doctor

You should call your health care provider if you experience the following conditions

• severe acute pain in the eyes or headache
• haloes or flashes
• reduced vision
• vision loss

Which age group is affected by glaucoma

All age groups can be affected with glaucoma. In primary congenital glaucoma, glaucoma will start in intrauterine life, while in the juvenile type of glaucoma, it will start at 15 years of age.

Complications Of Glaucoma:

What are the complications of glaucoma

One of the debleating complications of glaucoma is blindness, if not treated on time or if the treatment option is not chosen properly, then the patient will gradually become blind. Other complications of glaucoma include

• Recurrent attacks of pain
• Hyphema inside the anterior chamber
• Early development of cataract
• Corneal edema leading to scaring
• Choroidal affusion
• Periphery visual field loss encroaching the center with the passage of time.
• Blindness

Tips for Living With Glaucoma:

The patient should know in-depth about the disease. The main features in coping with glaucoma include lifestyle modification

• Eye drops should be used regularly and as described by the consulting doctor.
• Regular exercise should be advised on a regular basis to keep the intraocular pressure under normal limits
• A regular schedule of eye checkup should be maintained
• Maintain blood pressure and diabetes under normal limits
• Eat healthy food, rich in omega-3 fatty acid and anti-oxidants.
• Avoid smoking
• Elevate your head end during sleep.
• Patients who drive should get regular visual field checkup for the peripheral visual field.

What questions should I ask my doctor?

• What is the type of glaucoma I am suffering from?
• Compatibility of drugs I have been given with co-morbidities that I have, e.g asthma, cardiovascular disease, renal disease, etc.
• What are the timings of my eye drops?
• What are the complications of medicines that I have been advised of?
• When to call immediate help?
• What are the lifestyle modifications I need?
• When to come for a regular eye checkup?
• What are the other treatment options, if my glaucoma is not controlled with eye drops/ medications?

Conclusion:

Glaucoma is a blinding disease but blindness will rarely occur if the disease is detected well on time.  Once the disease has started the progression will continue but the speed of progression can be reduced, along with this the severity of signs and symptoms is reduced to a higher level.