Dictionary

dysplasia, cleidocranial See cleidocranial dysostosis.

dysplastic nevus A mole whose appearance is different from that of common moles. Dysplastic nevi are generally larger than ordinary moles, and they have irregular borders. Their color is often not uniform. They are usually flat, but parts may be raised above the skin surface. Dysplastic nevi can be precancerous. See cancer, skin.

dyspnea Difficult or labored breathing; shortness of breath. Dyspnea is a sign of serious disease of the airway, lungs, or heart. The onset of dyspnea should not be ignored; it is reason to seek medical attention.

dyspnoea See dyspnea.

Dupuytren’s contracture A localized formation of scar tissue in the palm of the hand within a tissue (fascia) beneath the skin of the palm that normally covers the tendons that pull the fingers into a grip. As Dupuytren’s contracture progresses, more of the fascia becomes thickened and shortened. Dimpling and puckering of the skin over…

duodenum The first part of the small intestine. The duodenum is a common site for peptic ulcer formation.

duplication, chromosome The addition of part of another chromosome to a chromosome. This is a common cause of genetic disease. The opposite of deletion.

dura mater The outermost and most fibrous of the three membranes (dura mater, arachnoid membrane, and pia mater) covering the brain and the spinal cord.

durable power of attorney A type of advance medical directive in which legal documents provide the power of attorney to another person in the case of an incapacitating medical condition. A durable power of attorney allows another person to make bank transactions, sign Social Security checks, apply for disability, or write checks to pay utility…

DVT Deep vein thrombosis.

dwarfism Abnormally short stature, which may be due to a variety of causes. Some forms of dwarfism are hereditary. The Little People of America (LPA) defines dwarfism as a medical or genetic condition that usually results in an adult height of 148 cm (4 feet 10 inches) or shorter, among both men and women. Also…

dwarfism, achondroplastic See achondroplasia.