Adson's test

[ădsənz]
n.
  1. A test for thoracic outlet syndrome in which the patient is seated and, with the head extended and turned to the side of the lesion, breathes deeply; a diminution or loss of radial pulse on the affected side is indicative of the syndrome.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.