Figure 7.

Varying degrees of severity of brachial plexus entrapment in thoracic outlet syndromes. A) Linear plexus with short segment of mild hyperintensity consistent with nerve irritative changes near the later border of the scalene triangle; B) Evidence of more restrictive fibrosis associated with narrowing and brightening of plexus elements near the scalene border – note linear plexus despite elevated shoulder; C) Short segment of marked hyperintensity with slight swelling; D) Severe multiple element abnormality with narrowed and swollen segments, and marked hyperintensity; E) Linear normal plexus with isolated focal impingement of C5 spinal nerve, just proximal to the scalene triangle; F) Fibrous band causing sharp downward distortion of mid and lower trunk proximal to scalene triangle, with second sharp upward distortion of lower trunk near scalene insertion at the first rib; G) Moderate restrictive impingement of plexus at scalene triangle causing generalized distortion of the course of the plexus with short segment of focal hyperintensity; H) Patient presenting with severe pain, numbness and weakness from progressive thoracic outlet syndrome – multiple points of sharp nerve course distortion with edema and hyperintensity affecting multiple brachial plexus elements.