constriction

1. [TA] A normally or pathologically constricted or narrowed portion of a structure. SYN: constrictio [TA]. SEE ALSO: stricture, stenosis. 2. The act or process of binding or contracting, becoming narrowed; the condition of being constricted. squeezed. 3. A subjective sensation of pressure or tightness, as if the body or any part were tightly bound or squeezed. [L. con-stringo, pp. -strictus, to draw together]

- broncho-aortic c. thoracic c. of esophagus.

- diaphragmatic c. of esophagus [TA] normal narrowing of the esophagus, demonstrated radiographically following a barium swallow, caused by the passage of the esophagus through the esophageal hiatus of the diaphragm. SYN: constrictio phrenica esophagea [TA], constrictio diaphragmatica esophagea, inferior esophageal c..

- esophageal constrictions three narrowings of the esophagus normally demonstrated radiographically following a barium swallow. SEE ALSO: pharyngoesophageal c., thoracic c. of esophagus, diaphragmatic c. of esophagus. SYN: impressions of esophagus.

- inferior esophageal c. SYN: diaphragmatic c. of esophagus.

- middle esophageal c. SYN: thoracic c. of esophagus.

- pharyngoesophageal c. [TA] normal narrowing of the alimentary tract, demonstrated radiographically following a barium swallow, at the junction of the pharynx with the esophagus (C5 vertebral level) caused by the tonic or active contraction of the cricopharyngeal part of the inferior constrictor of the pharynx (upper esophageal sphincter). SEE ALSO: cricopharyngeal part of inferior constrictor (muscle) of pharynx. SYN: constrictio pharyngoesophagealis [TA], upper esophageal c..

- primary c. the narrowing between the two arms of the chromosome represented by the centromere.

- pyloric c. circular groove on the external aspect of the gut at the gastroduodenal junction overlying the pyloric sphincter, thus demarcating the pyloric orifice.

- secondary c. a subsidiary narrowing of the chromosome associated in some cases with satellites, e.g., the short arms of acrocentric autosomes.

- thoracic c. of esophagus [TA] normal left-sided narrowing of the esophagus, demonstrated radiographically following a barium swallow, at the T4–T5 vertebral level, where the esophagus is impressed by the left main bronchus and the arch of the aorta. SYN: constrictio partis thoracicae esophagea [TA], broncho-aortic c., constrictio bronchoaortica esophagea, middle esophageal c..

- upper esophageal c. SYN: pharyngoesophageal c..

- constrictions of ureter normal physiological narrowings of the ureter observable in a pyelogram; the uppermost occurs at the origin of the ureter from the renal pelvis; a second occurs as the ureter crosses the iliac vessels and pelvic brim; the inferiormost occurs as the ureter penetrates the wall of the urinary bladder.

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con·stric·tion -'strik-shən n

1) an act or product of constricting

2) the quality or state of being constricted

3) something that constricts

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con·stric·tion (kən-strikґshən) [L. constringere, past part. constrictus, to draw together] a narrowed part of an organ or other structure; see also stenosis.