Ocular Surface Diseases
There are a number of conditions involving the ocular surface, including the following disorders.
Dry Eye Syndrome
Dry eye syndrome (also known as keratitis sicca) is one of the most common problems affecting the general population, causing problems that range in severity from mildly irritating to debilitating. Dry eye syndrome is a general term that describes changes to the front surface of the eye in response to a breakdown of the tear film that coats the ocular surface. This disturbance can lead to a multitude of symptoms, including burning, stinging, itching, tearing, foreign-body sensation, discharge, frequent blinking, mattering or caking of the eyelashes, redness, light-sensitivity, eye pain, and eye fatigue. Dry eye syndrome is often referred to as tear film dysfunction.
The condition is more common in women than men, and in middle-age and elderly people. The insufficient tear production may be traced to conditions that result in decreased corneal sensation or damage to the tear glands. These may include long-term contact lens wear and Sjogren’s syndrome, a chronic inflammatory disease in which many of the body’s normally moist membranes (such as those in the mouth and nose) lack sufficient moisture. An individual with dry eye syndrome/tear film dysfunction may have more than one condition causing the symptoms.
How is Dry Eye Diagnosed?
Many people with dry eye syndrome/tear film dysfunction have subtle signs that are not obvious on a general screening eye exam. For this reason, if the condition is suspected by you or your primary care doctor, a thorough evaluation will frequently be necessary. Depending on your signs, symptoms, history, and any comorbidities, your doctor may order tests ranging from Shirmer tear test to blood tests to check for systemic disease.
What is the Treatment for Dry Eye?
Most cases of dry eye can be treated by using artificial teardrops several times daily. Additional treatment options may involve:
- A non-medicated lubricating ointment placed in the eyes at bedtime to relieve the dryness normally felt upon wakening.
- Tear-conserving interventions such as punctal plugs to reduce tear drainage and treatments to the ocular surface to prevent evaporative tear loss. Warm compresses, eyelid scrubs, and oral flaxseed (2000 mg/day) oil with fish oil supplements have also been found to be useful in alleviating symptoms and decreasing the frequency of topical agents.
- Prescription medicines to encourage tear-production such as Restasisâ and Xiidraâ may also be used by your doctor.
- Topical ophthalmic steroids are helpful in controlling the acute inflammatory aspect of the disease.
Most people with dry eye syndrome who keep up their regimens as prescribed by their eye doctor are able to control their symptoms and function with minimal difficulty. Because of the complexities of dry eye syndrome, however, most people are never permanently “cured.”
Blepharitis is a chronic condition involving inflammation of the eyelids. It can be caused by malfunctioning oil glands near the base of the eyelashes, allergies, rosacea (a skin condition characterized by redness), or eye infections. Symptoms of blepharitis include:
- red and watery eyes
- itchy eyelids
- dandruff-like scales on the eyelashes and eyelids
It is not contagious and does not generally permanently affect vision.
How is Blepharitis Treated?
A systematic and long-term commitment to a regimen of eyelid margin hygiene is the basis of treatment of blepharitis. This includes:
- Applying warm compresses to the eyelids two to four times a day, and cleaning the eyelids with a cotton applicator soaked in a mixture of warm water and/or baby shampoo.
- Oral flaxseed (1000-2000 mg/day) oil with fish oil supplements to alleviate symptoms.
- Oral antibiotics, used for refractory cases of blepharitis.
- One- or two-month courses of tetracycline class oral agents to reduce symptoms in patients with more severe disease. Tetracycline, doxycycline, and minocycline are believed to not only reduce bacterial colonization but alter metabolism and reduce glandular dysfunction of the oil-producing glands of the eyelid.
Ocular Surface Squamous Neoplasia
Ocular surface squamous neoplasia (OSSN) encompasses a wide spectrum of abnormal-growth dysplastic squamous epithelial cells on the surface of the eye. These tumors typically appear in older people, especially those who have had significant exposure to sunlight.
Ocular surface neoplasia often appears as tiny growths on the surface of the eye and may be mistaken for pterygium.
What Are the Risk Factors for OSSN?
They likely involve a variety of environmental factors, including UV radiation and exposure to sun. OSSN can also be linked to viral infections, chemical carcinogens, and other environmental risk factors. It is well known that the prevalence of OSSN increases in populations that live near the equator. OSSN is also more common in Caucasians with light complexions and patients with xeroderma pigmentosum, a genetic condition that increases susceptibility to DNA alterations secondary to UV light.
The most common form of OSSN is conjunctival intraepithelial neoplasia (CIN), a noninvasive, slow-growing tumor that arises from a single mutated cell on the ocular surface. Rarer forms of OSSN include squamous cell carcinoma (SCC), a malignant lesion in which the dysplastic epithelial cells have penetrated the corneal basement membrane (gaining metastatic potential) and mucoepidermoid carcinoma, an aggressive variant of SCC, which may be clinically distinguishable from SCC only through special testing.
How is OSSN Treated?
The history of the lesion and number of prior treatments often dictate tumor management. Major breakthroughs in the diagnosis and treatment of the disease have occurred within the past two decades. These include increasing use of topical chemotherapeutic agents over surgery. Interferon-α2b, mitomycin C, and 5- fluorouracil have the advantage of treating the entire ocular surface and avoiding surgical complications such as positive tumor margins, scarring, and limbal stem cell deficiency. If the tumor is large or recurrent, surgical removal is often recommended. The Ocular Oncology Service at New York Eye and Ear Infirmary of Mount Sinai (NYEE) has extensive experience diagnosing and treating these often complex conditions.
Pterygium and Pinguecula
A pterygium (from the Greek word for “wing”) is an abnormal growth of tissue that extends from the conjunctiva (a membrane that covers the white of the eye) onto the cornea. Typically, a pterygium presents as a pinkish, triangular tissue that generally grows slowly, but in some cases may become so large it covers the pupil. Smaller pterygia can cause dryness, redness, burning, itching, and/or an unacceptable cosmetic appearance. Larger pterygia can cause blurred vision by altering the shape of the cornea, or producing astigmatism. Pterygia are more common in areas of the world nearest the equator. They are associated with early exposure to the sun, especially during childhood and teen years.
What is a Pinguecula?
A pterygium may be confused with a pingueculum. A pingueculum looks like a yellowish patch or bump on the white surface (sclera) of the eye. It grows on the conjunctiva, similar to a pterygium, but does not grow over the cornea. A pingueculum is a benign degeneration of the conjunctiva. It is caused by damage from exposure to ultraviolet light from the sun.
How are Pterygium and Pingueculas Treated?
Most pterygia are treated with artificial teardrops that relieve irritation and burning. Anti-allergy drops or even anti-inflammatory drops may be used for more significant symptoms. If vision is affected or if the pterygia become enlarged, surgical removal may be necessary. To prevent re-growth of the pterygium (which can be a late complication), surgeons may transplant conjunctiva from another part of the eye to the area where the pterygium was removed, as well as use anti-metabolite drugs or apply radiation to the area. Pinguecula, on the other hand, are usually asymptomatic and may be treated conservatively with artificial tears and anti-inflammatory drops. Rarely do they require surgery.