Common Eye Diseases

Common Eye Diseases

Cataracts
A cataract is an opaque section in the lens inside the eye. Cataracts usually appear in people 60 years old and above. Diabetics are also prone to developing cataracts. Symptoms include progressive blurring of vision leading to severely unclear vision. Cataracts are treated by surgically removing the opaque lens and replacing it with an artificial one. This technique is known as phacoemulsification with intraocular lens implantation, and it restores clear vision.

Infections
Conjunctivitis is an infection of the semitransparent membrane covering the eyeball called the conjunctiva. It can be caused either by a virus or bacteria.

Symptoms of viral conjunctivitis include itching, tearing, copious eye discharge leading to matted eyelids in the morning, sensitivity to light and swollen lymph nodes near the ear area of the affected side. This is treated with cold compress and at times, prophylactic antibiotic drops and anti-inflammatory eye drops.

Symptoms of bacterial conjunctivitis are redness, swelling of the interior of the eyelid and moderate to heavy discharge. This is treated with antimicrobial eyedrops.

Keratitis is an infection of the outer lens of the eye caused either by a virus or bacteria. Symptoms include severe blurring of vision and a corneal lesion known as an ulcer. As with bacterial conjunctivitis, antimicrobial eyedrops treat this eye disease, and patients are also closely monitored. Keratitis may leave a corneal scar, because of the attempt of the cornea to heal.

Diabetic Retinopathy
Poor management of diabetes mellitus can lead to diabetic retinopathy, a potentially blinding disease. It affects the small blood vessels in the retina due to the inability of the retina to use glucose as energy. The retina tries to compensate by building new blood vessels which are not as structurally sound as the natural ones. These new blood vessels tend to rupture, causing bleeding within the eye. Diabetic retinopathy must be detected early to allow laser therapy to restore or preserve vision.

Glaucoma
Glaucoma is characterized by damage to the optic nerve from pressure within the eye. Narrowing of one's field of vision is its primary symptom. The elderly are more likely to develop this disease, as well as people with a family history of glaucoma, and people with errors of refraction.

Errors of Refraction
Myopia, also known as nearsightedness, is a condition wherein the image seen by the eye is focused in front of the retina, rather than on it. This causes the image to blur. Nearsighted people usually use eyeglasses or contact lenses to bring the image seen onto the retina. Also, laser in-situ keratomileusis (LASIK) is a recently developed surgery that reduces the need for prescription lenses.

On the other hand, hyperopia, or farsightedness, is a condition wherein the image seen by the eye is focused on the back of the retina. This also results in a blurred image. Like myopia, prescription lenses correct this error of refraction.

Finally, astigmatism is an imbalance in the curvature of the cornea. This is a very common refractive error, and it results in blurry vision. Lenses are also used to treat this.

Dry Eye
The eyes are constantly kept moist with tears, which are a combination of mucus, oil, and water. Dry eye occurs when there are defects in the tear gland, imbalances in the tear mixture, or structural defects in the eye or eyelid. It is a chronic condition and complete relief is rarely achieved. Application of artificial tears is the most common treatment for this disease.

Macular Degeneration
Macular degeneration is a disease that mostly targets the elderly. Smokers, diabetics, and anyone with existing damage to the macula are all at risk of developing this.

The macula is the center of the retina and is responsible for 20/20 vision. The degeneration of the macula causes the cells to atrophy and eventually die.

Macular degeneration must be found early for treatment to be effective. Laser treatment in particular has improved the treatment of this condition.

Ocular Allergy
Ocular allergy is the eye's allergic reaction to an irritant or allergen. These allergens can come from anywhere. Mainstays of treatment are antihistamine eyedrops, though severe cases may need steroid therapy.

Strabismus
Strabismus is any misalignment of one or both eyes. It commonly appears in children below the age of two and makes the patient appeared cross-eyed. Refraction errors between the two eyes cause the optical center in the brain to focus on the eye with the clearer image and suppress the image from the eye with the higher refraction.

Glasses may be prescribed to improve vision. Surgery to adjust the position of the eye muscles may be needed as a more permanent treatment.

Thyroid Eye Disease
Thyroid eye disease, or thyroid ophthalmopathy, is common in patients with Graves' disease, a form of hyperthyroidism. Deposits of anti-thyroid antibodies collect behind the eye, causing the eyeball to protrude. This also causes the eyelid muscles to retract, making closing the eyes more difficult. Meanwhile the eye muscles enlarge, giving the patient the characteristic “thyroid stare” or bulging eyes. Initial treatment usually focuses on maintaining eye moisture, with subsequent management varying on a case to case basis.

General ophthalmology 13th,   1992 edition
Vaughan et al
Current ocular therapy- 4
by Frederick T. Fraunfelder and F. Hampton Roy 1995

Note:   This information is not intended to be used as a substitute for professional medical advise, diagnosis or treatment.   If you or someone you know have any of the symptoms mentioned above, it is advisable to seek professional help.

At The Medical City, we have a complete line-up of eye specialists.

Tel. No. (632) 988-1000 / (632) 988-7000 Ext. 6444