Understanding Eye Disorders

Understanding Eye Disorders

The eyes are complex organs designed to capture light and send the information they collect to the brain for interpretation. Because they have so many working parts, eyes can suffer from a variety of disorders, including vision problems, inflammation and excessive dryness. Here’s a look at common eye issues and how to treat them.

Taking a look at the eye

The eye is basically a hollow, fluid-filled ball with three layers: the sclera (the white part), the retina (the part that collects light) and the uvea (the muscular layer). A thin mucus-like membrane called the conjunctiva covers the eyelid and part of the eyeball. 

The eyeball is also divided into two fluid-filled sections: the aqueous humor in the front that supplies nutrients, and a jelly-like fluid in the back called the vitreous humor. The pressure generated by these fluids helps the eyeball maintain a round shape.

Light enters into your eye through a protective dome called the cornea and then travels through your pupil (the black part). Around the pupil is the iris—the colored area of the eye—that controls the amount of light that comes into the eye by contracting or relaxing certain muscles. Light then goes through the lens, which can change its thickness to focus the light properly on the retina.

The retina contains two types of light-sensitive nerve cells (cones and rods) called photoreceptors. Cones and rods have different functions, but both convert light into electrical signals that are carried to the brain. The brain processes the signals, and this accounts for what you actually see.

Sometimes there can be problems with eye health. It’s important to remember that eye conditions should not be self-treated. Be sure to check with your physician or pharmacist before trying new therapies for your eyes.

Eye Disorders

Vision problems. Vision problems are on the rise in the United States, according to a report just released by Prevent Blindness America and the National Eye Institute. Symptoms include vision loss, altered eye movements, pain, visual field loss, bulging eyes, double vision and headaches. These symptoms typically develop as a result of a problem in the eye, but occasionally they indicate a problem elsewhere in the body. Eyeglasses or contact lenses are a common treatment for vision disturbances, along with laser vision correction such as LASIK (laser-assisted in situ keratomileusis). Currently, no alternative therapies have strong scientific evidence to support their effectiveness in improving vision, but some studies suggest that acupuncture may help treat eye movement disorders. However, this natural remedy has been given a Natural Standard evidence grade of C, meaning that evidence is still unclear or conflicting. More research is needed to confirm the potential benefits of acupuncture for vision improvement. 

Conjunctivitis. Also known as pink eye, conjunctivitis is an inflammation or infection of the conjunctiva. Symptoms include redness, itchiness, blurred vision, sensitivity to light, a gritty sensation, crust formation and tearing. 

Contagious bacteria or viruses generally cause conjunctivitis. For bacterial infections, your doctor may prescribe antibiotic eye drops or ointment. Povidone-iodine eye drops may be used in some children. Viral conjunctivitis can be treated with over-the-counter products such as naphazoline (VasoClear). Your symptoms may worsen in the first three to five days but will clear naturally over two to three weeks.

Iodine, an element required by humans for the proper production of thyroid hormones, has a Natural Standard evidence grade of B for conjunctivitis, meaning that it is supported by good scientific evidence for this condition. Iodine is obtained from the human diet and has been shown to effectively manage pink eye as well as treat conjunctivitis.

Allergies can also cause conjunctivitis. Many different types of eye drops for allergic conjunctivitis can be used: antihistamines, mast cell stabilizers, steroids and anti-inflammatories. It is important to use any medication prescribed as directed to prevent conjunctivitis from coming back.

Uveitis. This condition occurs when any part of your uvea becomes inflamed. It can be quite serious and may lead to permanent vision loss. Symptoms include light sensitivity, blurred vision and pain. Early diagnosis and treatment are important. 

Uveitis is most common in people ages 20 to 50 and can be associated with autoimmune disorders. Your doctor may prescribe anti-inflammatory medications such as ophthalmic corticosteroids or nonsteroidal anti-inflammatory drugs. If uveitis is caused by an infection, antibiotics or antiviral medications may be given to control the infection. 

Echinacea, turmeric and vitamin E have all been studied as natural treatments for uveitis. However, these alternative therapies have a Natural Standard evidence grade of C, and more research is needed to understand their potential in treating this eye disorder.

Xerophthalmia (dry eye). This condition, in which the eyes do not produce enough tears, is extremely common with old age and is more prevalent in women. Symptoms of dry eye range from mild irritation to severe discomfort and sensitivity to light. There are several conditions and medications that can lead to dry eye syndrome or make it worse. Medications that may cause dry, irritated eyes include antihistamines (such as diphenhydramine or Benadryl®), anticholinergics (such as dicyclomine or Bentyl®), digitalis derivatives (such as digoxin or Lanoxin®), some high blood pressure pills (guanethidine, reserpine and thiazide diuretics), indomethacin (Indocin®), phenothiazines (such as prochlorperazine or Compazine®) and medications for malaria (such as chloroquine or Aralen®) and tuberculosis (including ethambutol or Myambutol®). 

The first step in the treatment of dry eye is to remove or reduce the cause. Because vitamin A deficiency can cause dry eye, supplementing with the vitamin can help. Supplementing with fish oil, flax and vitamin E can also help dry eyes. The prescription medication Lacrisert has also been shown to be helpful in some individuals with severe dry eyes. Reducing the amount of time you wear contact lenses and taking breaks from intense visual work are also first steps in preventing and treating dry eye. 

Artificial teardrops are the main treatment for dry eye. Restasis is a prescription eye drop that helps increase tear production. Other medications, including anti-inflammatory eye drops and eye ointments, may also be used.

Keratitis. This inflammation of the cornea can be caused by infection, injury or severe dryness. Symptoms include pain, excessive tear production, bloodshot eyes and sensitivity to light and are often accompanied by blurred or hazy vision. Risk factors include improper use of contact lenses, illnesses that reduce the ability to fight infections, poor hygiene and poor nutrition. If herpes simplex virus is the cause, you will notice a small white spot on your cornea. 

Keratitis is usually treated with antibacterial or antifungal eye drops. In severe cases, you may be prescribed oral antibiotics to eliminate the infection, along with steroid eye drops to reduce inflammation. Corneal scarring or thinning may occur and, in some cases, requires cornea transplantation. Some research has been conducted on thymus extract, which is taken from the thymus gland of calves and encapsulated. However, there is unclear or conflicting evidence as to the efficacy of this therapy, which has received a Natural Standard evidence grade of C.

When to see your doctor

If you have symptoms of any of these eye disorders, it’s a good idea to visit an eye doctor. However, some eye diseases cause few or no symptoms in their early stages, so it is important to have a routine eye examination every one to two years. 

There are two types of eye doctors: opticians, who prescribe and dispense eyeglasses; and optometrists, who conduct eye exams and may diagnose eye problems. Ophthalmologists may also provide routine vision care services such as prescribing glasses and contact lenses.

Read more about Enhancing Eye Health Naturally.

Dr. Catherine Ulbricht is one of the founders of Natural Standard, a key Wellness Times content partner. Watch this video about Natural Standard featuring Dr. Ulbricht.

Catherine Ulbricht, PharmD's picture

Dr. Ulbricht is a cofounder of Natural Standard Research Collaboration. She serves as Senior Attending Pharmacist, Massachusetts General Hospital and Adjunct/Assistant Clinical Professor at multiple universities. She serves on the Editorial Board of Harvard Health Publications, Journal of the American Nutraceutical Association, Journal of Integrative Cancer Medicine, Pharmacy Practice News and many others. She is Editor-in-Chief of the Journal of Dietary Supplements. Her background includes experience in the areas of quality improvement, healthcare informatics, regulatory affairs, clinical trial protocol analysis and drug therapy decision-support. She has also been trained in physical therapy and chiropractic care. For more information on the Natural Standard Research Collaboration visit NaturalStandard.com.

July 5th, 2012
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