Category: P

A laser-surgery operation on the clear surface (cornea) of the eye to correct nearsightedness, farsightedness, or astigmatism; also known as PRK. The procedure has largely been replaced by lasik. The removal of microscopic layers of corneal cells and the resculpting of the cornea with an excimer laser. The procedure is used to correct myopia. Its…

An imaging technique that combines nuclear medicine and chemical analysis to enable physicians to observe the function of certain organs of the body. After the person has an injection of a radioactive compound, cross-sectional images are taken by a special camera to demonstrate how an organ or tissue is metabolizing the injected substance. This can…

An acute infection that produces a collection of pus between the tonsils and the muscle at the back of the mouth. Peritonsillar abscess occurs most commonly in young adults and is usually caused by a Streptococcus infection, but may be due to other types of bacteria. Symptoms include severe pain when swallowing, fever, and lockjaw…

A prenatal diagnostic test to detect genetic abnormalities and infection in the fetus. Percutaneous umbilical cord blood sampling (PUBS) is used after the 17th week of pregnancy and only when other diagnostic procedures have not provided a definitive result. Because it is a very complicated and difficult procedure, PUBS is performed exclusively by physicians who…

A disease in which one or more raw areas develop in the membranes lining the esophagus, stomach, and duodenum. The affected areas are damaged by strong acids and digestive enzymes secreted by stomach glands. The two main types of peptic ulcer disease are duodenal ulcers and gastric ulcers. Duodenal ulcers occur primarily on the duodenal…

A blistering disease caused by an autoimmune reaction toward proteins in the skin. Typically, men or women between 40 and 60 years old are affected. Painful and itchy blisters and sores may cover a significant portion of the body. Blisters may first appear in the mouth. Diagnosis is made through biopsy and blood tests. Treatment…

A device that measures airflow, called peak expiratory flow rate, which is one measure of lung function. The person being tested blows quickly and forcefully into the device, and a reading indicates how open the airways are. Peak flow meters are used primarily to determine the severity of asthma and may be used as a…

Testing of blood or DNA to identify the biological father of a child. Most often, blood samples are taken from an infant soon after birth, the possible father, and sometimes the mother. These samples are then analyzed for compatibility. For DNA testing on blood or a swab of cells from inside the cheek, the DNA…

Inflammation of the tendon that connects the kneecap to the shinbone. The cause of patellar tendinitis is overuse, usually during athletic activity, which produces microscopic tears in the tiny fibers of the tissue. These tears can stretch the patellar tendon and cause painful inflammation. Symptoms include pain when running or jogging and localized tenderness when…

A growth on the parathyroid glands that usually results in excessive production of parathyroid hormone. Excess levels of parathyroid hormone produce elevated calcium in the blood and urine, which can lead to kidney damage and the formation of calcium- containing kidney stones. When the kidneys excrete large amounts of calcium, extreme thirst and frequent urination…