Eyeglasses
Lenses or prisms worn in front of the eyes to correct defects of vision or to protect the eyes. The most common form of eyeglasses consists of a pair of glass lenses in a metal or plastic frame fitted to the bridge of the nose. The frame is held in place by bows, or arms, that grip the head or hook around the ears. Lenses made of hard plastic are often worn for their increased safety and light weight.
The lenses of eyeglasses are ground with different curvatures to correct various vision defects. Two or three different lens shapes may be combined in a single set of eyeglasses to make bifocals or trifocals, which allow simultaneous correction of nearsightedness and farsightedness.
Contact lenses are worn under the eyelids, directly over the eyeball. They lessen the inconvenience and danger of breakage of ordinary eyeglasses. Contact lenses cover only the cornea of the eye; a special molding process permits precision fitting to the curvature of the cornea to minimize irritation. So-called soft lenses are made from plastic that molds itself to the shape of the cornea. Research has been done with implanted lenses that reshape the cornea to correct defects.
Eyeglasses are worn to protect the eyes from the sun (sunglasses), from welding flames (welder's glasses), from flying particles of metal (safety goggles), or from the wind (aviator's or driver's goggles). A diver's goggles, which allow clear vision under water, are another form of eyeglasses.
Conjunctivitis
An inflammation of the conjunctiva, a mucous membrane that lines the inner surface of the eyelids. Conjunctivitis may be caused by infection, allergy, or injury and is marked by redness and swelling. Acute conjunctivitis is commonly called pinkeye and can be caused by bacterial or viral infection. In newborn babies it may result from the gonorrhea bacterium (gonorrheal conjunctivitis) or from the bacterium Chlamydia trachomatis (inclusive conjunctivitis). Fly-borne Chlamydia trachomatis causes trachoma, a severe form of conjunctivitis that often results in blindness. Bacterial conjunctivitis is usually treated with antibiotics and sulfonamides.
Sjogren's syndrome is an incurable, autoimmune disorder striking 2-4 million Americans, many of whom go undiagnosed. Nine out of ten individuals with Sjogren's are women.
In Sjogren's syndrome, the body's immune system mistakes its own moisture producing glands for foreign invaders. The immune system then attacks and destroys these glands causing the hallmark symptoms of dry eyes and dry mouth.
Like lupus, Sjogren's can also damage vital organs of the body with symptoms that may plateau, worsen, or go into remission. Some people may only experience the mild symptoms of dry eyes and mouth, while others go through cycles of good health followed by severe disease.
Many patients are able to treat problems symptomatically. Others are forced to cope with blurred vision, constant eye discomfort, recurrent mouth infections, swollen parotid glands, hoarseness and difficulty in swallowing and eating. In addition to affecting the eyes and mouth, Sjogren's syndrome can cause skin, nose and vaginal dryness and can affect other organs of the body, including kidneys, blood vessels, lungs, liver, pancreas and brain.