CT-angiography performed with arms in both neutral and raised positions clearly demonstrates dynamically induced compression of right subclavian artery in costoclavicular space. Compression is caused by abnormal fused cervical and first ribs. Findings are consistent with arterial thoracic outlet syndrome.
Condition is complicated by formation of saccular aneurysm of right subclavian artery at the site of damage (best seen when arms lowered) and brachial artery embolism.