laryngeal palsy Paralysis of the larynx (voice box) that is caused by damage to the recurrent laryngeal nerve, which supplies the larynx (voice box), or its parent nerve, the vagus nerve, which originates in the brain stem and runs down to the colon. In laryngeal palsy, the larynx is paralyzed on the side where the…
laryngeal nerve, recurrent One of the branches of the vagus nerve, a long and important nerve that originates in the brain stem. After the recurrent laryngeal nerve leaves the vagus nerve, it goes down into the chest and then loops back up, to supply nerves to the larynx (the voice box). It is said to…
laryngeal Having to do with the larynx (voice box).
large cell carcinoma A term used to describe a microscopically identified variant of certain cancers, for example lung cancers, in which the abnormal cells are particularly large.
laparotomy An operation to open the abdomen. For example, laparotomy is used to remove cancer of the intestines or repair bowel blockage.
laparoscopy A type of surgery in which small incisions are made in the abdominal wall through which a laparoscope and other instruments can be placed to permit structures within the abdomen and pelvis to be seen. A variety of probes or other instruments can also be pushed through these small incisions in the skin. In…
lanugo Downy hair on the body of a fetus or newborn baby. Lanugo is the first hair to be produced by the fetal hair follicles, and it usually appears on the fetus at about 5 months of gestation. Lanugo is very fine, soft, and usually unpigmented. Although lanugo is normally shed before birth, around 7…
Langerhans cell histiocytosis The preferred name for what was once called histiocytosis X. Langerhans cell histiocytosis refers to several disorders in which histiocytes start to multiply and proliferate abnormally. The result can be tissue damage, pain, the development of tumor-like lumps, fatigue, and other symptoms. If histiocytosis affects the pituitary gland, diabetes insipidus may also…
Landing disease See GM1-gangliosidosis.
Landau-Kleffner syndrome A disorder with onset in childhood characterized by the loss of speech and recognition of spoken language. Patients may also have behavioral disorders and seizures and may develop behaviors similar to autism. See also autism; epilepsy; seizure; seizure disorder.
Lancet, The A well-known medical journal published in England. Founded in 1823, The Lancet is the longest-running medical journal in the world.
lancet A small, pointed knife that is used to prick a finger for a blood test.