CORNEAL AND OCULAR SURFACE



Corneal Abrasion

A corneal abrasion is a painful scratch of the surface of the clear front surface of the eye, otherwise known as the cornea. It may occur when something blows into or hits your eye scratching the cornea.

Common causes of abrasions are getting poked in the eye or rubbing the eye when a foreign body is present, such as dust or sand. Corneal abrasions can be painful and cause severe light sensitivity.

If you know something has scratched your eye, it's very important to see your Eye Health Doctor for proper treatment.

Corneal Foreign Body

A corneal foreign body is an object (eg, metal, glass, wood, plastic, sand) either superficially or set into the cornea of the eye. If corneal foreign bodies are not removed in a timely manner, they can cause prolonged pain and may lead to infection.

Superficial foreign bodies: these stick to the front of the eye or may be trapped under one of the eyelids causing irritation, but do not pass through the ocular surface.

Penetrating foreign bodies: this type of foreign body is more serious, actually going through the outer layer and potentially enter the eye. These objects are usually travelling at high speed and are commonly made of metal and need immediate medical attention.

Conjunctivitis

Conjunctivitis commonly known as pinkeye, is an inflammation of the conjunctiva, the clear membrane that covers the white part of the eye and the inner surface of the eyelids. These membranes react to a wide range of bacteria, viruses, environmental irritants and toxic agents, as well as to underlying diseases within the body.
Either a bacterial or a viral infection may cause conjunctivitis.

Viral conjunctivitis is the most common type. It may last from one to several weeks and is frequently accompanied by a respiratory infection (or cold). Antibiotic drops or ointments usually do not help, but symptomatic treatment such as cool compresses or over-the-counter eye drops can be used to relieve symptoms while the infection runs it course.

Bacterial conjunctivitis can be treated with a variety of antibiotic eye drops or ointments, which usually cure the infection within a few days.

Conjunctivitis can be very contagious. If you think you may have conjunctivitis see you doctor for possible treatment and take these measures to prevent spreading the virus:

  • Keep your hands away from your eyes;
  • Thoroughly wash hands before and after applying eye medications;
  • Do not share towels, washcloths, cosmetics or eyedrops with others;
  • Seek treatment promptly.

Not all cases of conjunctivitis are caused by an infection. Allergies can cause conjunctivitis, too. Typically, people with allergic conjunctivitis have itchy eyes, especially in spring and fall.

While conjunctivitis can be alarming because it may make the eyes extremely red and can spread rapidly, it's a fairly common condition and usually causes no long-term eye or vision damage.

Common symptoms of conjunctivitis may include:

  • redness of the eyes
  • sensitivity to light
  • blurred vision
  • burning or itching of the eye
  • scratchy feeling in the eye
  • discharge that may be watery or contain mucous

Corneal Ulcer

A corneal ulcer is an erosion or open sore on the clear front surface of the eye called the cornea. If the cornea becomes inflamed due to infection or injury and is not treated properly, an ulcer may develop. A corneal ulcer is a serious condition that must be treated promptly to avoid lasting vision problems. Although eye drops are very affective in treating corneal ulcers, they can sometimes cause scarring and lead to severe loss of vision and even blindness.

Corneal ulcers or infections may also be caused by:

  • Eyelids that do not fully close, such as with Bell's palsy or stroke
  • Scratches (abrasions) on the surface of the eye
  • Severe dry eye
  • Various infections and inflammatory disorders
  • Foreign objects in the eye
  • Overuse, bad hygiene or improper use of contact lenses

TREATMENTS FOR CORNEAL DISORDERS

-Most Corneal Disorders can be easily and sucessfully treated with drops however, in rare cases when surgical intervention is necessary.

The cornea is the transparent "window" of the eye that permits light to enter the pupil and to focus on the retina to produce clear vision. Normally crystal clear and dome-shaped (like a contact lens), it can become cloudy or misshapen as a consequence of injury, disease or surgical complications, thereby greatly reducing vision.

Corneal Transplant

Corneal transplantation (termed keratoplasty) using human donor corneas are the most successful of organ transplants, enjoying a 95% favorable prognosis in most cases. Thanks to the world's best network of eye banks, in the USA approximately 40,000 cornea transplants are performed annually on an elective (i.e. scheduled) basis.


Corneal Transplant


Only the central portion of the cornea is involved in transplantation. The surgeon removes a circular disc of the patient's cornea and replaces it with a similarly sized disc of donor cornea, which is then secured with microscopically fine sutures that are 1/10th the diameter of a human hair. Despite the precision involved, this surgery is performed on an ambulatory outpatient basis and in straightforward cases requires only 30 minutes to complete. In eyes with more substantial abnormalities of the iris and lens, Dr. Kenyon has devised techniques to combine cornea transplants with cataract removal, intraocular lens implantation or exchange, and repair of damage to the iris and pupil. Sutures are removed or adjusted to reduce astigmatism on an individual basis. Thus glasses or contact lens will generally not be prescribed until the transplant has become stable and healed, usually after 3 months.

For 40 years, diseases and surgery of the cornea and ocular surface have been a major interest of Eye Health's corneal specialist, Kenneth R. Kenyon, MD. Beginning with a cornea transplant, the first operation he ever witnessed as a medical student, Kenyon has remained devoted to the development of this increasingly important sub-specialty.

Dr. Kenyon has adapted the technique of amnion membrane transplantation for use in conjunction with corneal transplants to treat eyes with loss of corneal sensation following infection or injury, and has also greatly improved the prognosis for these so-called high-risk keratoplasties.

OTHER CORNEAL DISORDERS

Allergies- Allergies affecting the eye are fairly common. The most common allergies are those related to pollen, particularly when the weather is warm and dry. Symptoms can include redness, itching, tearing, burning, stinging, and watery discharge, although they are not usually severe enough to require medical attention. Antihistamine decongestant eyedrops can effectively reduce these symptoms, as does rain and cooler weather, which decreases the amount of pollen in the air.

An increasing number of eye allergy cases are related to medications and contact lens wear. Also, animal hair and certain cosmetics, such as mascara, face creams, and eyebrow pencil, can cause allergies that affect the eye. Touching or rubbing eyes after handling nail polish, soaps, or chemicals may cause an allergic reaction. Some people have sensitivity to lip gloss and eye makeup. Allergy symptoms are temporary and can eliminated by not having contact with the offending cosmetic or detergent.

Corneal Dystrophies
A corneal dystrophy is a condition in which one or more parts of the cornea lose their normal clarity due to a buildup of cloudy material. There are over 20 corneal dystrophies that affect all parts of the cornea. These diseases share many traits:

    • They are usually inherited.
    • They affect the right and left eyes equally.
    • They are not caused by outside factors, such as injury or diet.
    • Most progress gradually.
    • Most usually begin in one of the five corneal layers and may later spread to nearby layers.
    • Most do not affect other parts of the body, nor are they related to diseases affecting other parts of the eye or body.
    • Most can occur in otherwise totally healthy people, male or female.

Corneal dystrophies affect vision in widely differing ways. Some cause severe visual impairment, while a few cause no vision problems and are discovered during a routine eye examination. Other dystrophies may cause repeated episodes of pain without leading to permanent loss of vision.

Pterygium/Pinguecula

Pterygium

Pterygium are masses or growths of benign fibrous tissue with blood vessels (fibrovascular), typically located on the surface of the sclera (white part of the eye). These triangular masses of tissue can eventually grow over part of the cornea causing interference in proper vision. The cause of these benign growths may be irritation from dust and wind or extended exposure to sun /UV rays. Some people have no symptoms, while others may have redness or blurred vision. Pterygia that are chronically inflamed can become itchy and red. If a patient is having no symptoms from their pterygia no treatment is necessary.


Pterygium


How a Pterygium Is Treated

Treatment depends on the pterygium's size, location on the cornea and the symptoms it causes. If a pterygium is small but becomes inflamed, your eye doctor may prescribe lubricants or possibly a mild steroid eye drop to reduce redness and irritation. In some cases, surgical removal of the pterygium is necessary especially if it is growing into the visual pathway.
Pterygium Excision/Congunctival Autograft.

Starting in 1978, Dr. Kenyon devised the surgical technique of conjunctival autograft for treatment of localized conjunctival diseases such as the pterygium (an inflammation of the conjunctiva extending on to the cornea which commonly affects fisherman, construction workers and others exposed to sun & wind), thereby improving the prognosis for cure from 50% to 95%. This surgery has become the technique used universally for treating such disorders.

Pinguecula

Pingueculae are yellowish, slightly raised masses of tissue that form on the surface of the white part of your eye (sclera) close to the edge of the cornea. They are typically found in the open space between your eyelids (palpebral fissure), which also happens to be the area exposed to the sun. These benign bunches of tissue are somewhat like the Pterygium we spoke of previously, but do not extend over the cornea. Depending on size and growth, a pinguela can progress into a pterygium.


Pinguecula


Pingueculae are more common in middle-aged or older people who spend a lot of time in the sun, especially those whose occupation is outdoors (ie. Fisherman, construction workers, farmers, lifguards). Inn addition, being without proper eye protection increases chances of developing pingueculae.


The National Eye Institute (NEI) is part of the National Institutes of Health (NIH) and is the Federal government's lead agency for vision research that leads to sight-saving treatments and plays a key role in reducing visual impairment and blindness.