Backwards displacement of the manubrium causes crimping of the great vessels in patients with thoracic outlet syndrome (TOS): MRI/MRA/MRV
James D. Collins1,
Ernestina H. Saxton2,
Samuel S. Ahn3,
Hugh Gelabert3 and
Alfred Carnes1
1 Radiological Sciences
2 Neurology
3 Vascular Surgery, UCLA, Los Angeles, CA
ABSTRACT
Rounding of the shoulders increases the slope of the first ribs and asymmetrically displaces the manubrium posteriorly. This compresses the retrosternal fat with the involuted thymus gland and the left brachiocephalic vein against the brachiocephalic trunk. This displaces the aorta posteriorly and crimps (like a water hose) the great vessels: right brachiocephalic vein with the superior vena cava, common carotid arteries, subclavian arteries with binding nerve roots and vertebral arteries. Bilateral MRI/MRA/MRV displays costoclavicular compression and crimping of the great vessels that trigger complaints of TOS: facial, back and upper and lower extremity pain; numbness, tingling and edema; visual blurring and "floaters"; syncope and headache (FASEB 2003; 17:A784). Monitored multiplanar images with abduction external rotation, 2D Time of Flight MRA/MRV without contrast, were acquired on a 1.5 Tesla GE Signa LX unit, 44 cm field of view, 521 x 256 matrix and saline water bags to enhance signal to noise ratio. Two patients were selected, one following acute trauma, the other with repetitive strain injury. The second patient was misdiagnosed and underwent acromioclavicular joint surgery with a resultant unstable joint. Both patients developed laxity of the sling/erector muscles and round shoulders. Both displayed crimping of the great vessels and costoclavicular compression with TOS symptoms.
