THORACIC OUTLET SYNDROME IN A THROWING ATHLETE DIAGNOSED WITH MRI ANDMRA

Thoracic outlet syndrome comprises the clinical manifestations in the arm caused by compression of the neurovascular bundle as it leaves the thoracic inlet. The neurovascular bundle is composed of the subclavia n artery, the subclavian vein, and the brachial plexus, The symptoms o f thoracic outlet or inlet syndrome are most often caused by compressi on of the nerves of the brachial plexus, which is involved in up to 98 % of cases; the remainder are due to vascular compression, MRI with MR A demonstrates well the anatomy of the brachial plexus as well as any vascular compression or occlusion. The relationship of the axillary an d subclavian vein to the first rib and subclavius muscle also can be d emonstrated, We present a college baseball player who presented with n umbness in the fingers of his throwing hand when throwing a baseball. Evaluation with spin-echo and two-dimensional time-of-flight MR angiog raphic (MRA) imaging of the thoracic outlet region revealed obstructio n of the subclavian vein with the arm abducted, To our knowledge, no s uch cases have been diagnosed previously with MRI.