Stenosis

STENOSIS (stenosis), narrowing of this or that physiological opening, artery, esophagus, intestine, larynx, etc. Stenosis can be organic, based on an increase in tissue mass at the site of narrowing. This includes cancerous stenosis or stenosis on the basis of chronic inflammations or as a result of the deposition of various substances in the wall, for example, lipoids in atherosclerosis of blood vessels. Non-organic, or functional stenosis is usually associated with spasmodic phenomena when the musculature of an organ undergoes sharp contraction; such is the pyloric spasm in infants, spasm of arteries in various angioneuroses, etc. Between functional stenosis, which is more correctly called spasm, and organic stenosis, however, one should not make an absolute opposition and precisely because functional-spasmodic processes, with prolonged existence as a rule, lead to organic narrowing of the opening (pylorospasm-pylorostenosis, hypertension-arteriolosclerosis, etc.) due to hypertrophy primarily of those elements which directly participate in contraction and which give the walls elastic properties (smooth muscle, elastic fibers). The consequences of stenosis vary depending on the importance of the organ being narrowed, the duration and character of the process itself leading to stenosis.