Professional Description:
A continuous musical sound caused by narrowing of the lumen of a respiratory passageway. Often noted only by the use of a stethoscope, it occurs in asthma, croup, hay fever, mitral stenosis, and bronchitis. It may result from asthma, tumours, foreign body airway obstructions, bronchial spasm, pulmonary infections, emphysema and other chronic obstructive lung diseases, or pulmonary edema.