Print this pageComputed Tomography (CT) Angiography to Evaluate Thoracic Outlet Neurovascular Compression
Ravishankar Hasanadka, MD, Jonathan B. Towne, MD, Gary R. Seabrook, MD; Kellie R. Brown, MD, Brian D. Lewis, MD and William D. Foley, MD
Division of Vascular Surgery, Department of General Surgery, Medical College of Wisconsin, Milwaukee, WI
Objectives: To evaluate the efficacy of CT angiography with upper extremity hyperabduction as an objective test to diagnose thoracic outlet syndrome.
Methods: Over five years, 43 patients were treated surgically for thoracic outlet syndrome--21 patients presenting with neurogenic symptoms; 20 with venous symptoms, 18 of which were thrombosed; and two with artery aneurysms. Of the 43 operations, 39 were transaxillary first rib resection with two concominant cervical rib resections, and four were supraclavicular cervical rib resections, two of which included aneurysm resections. Patients with neurogenic symptoms were initially evaluated with a history and physical exam. If the diagnosis was unclear, adjunctive tests [CT angiography (n=6), arterial duplex (n=8), and magnetic resonance arteriography (n=2)] were performed to help establish the diagnosis. CT angiograms were performed with a 16-slice multidetector row CT scanner with submillimeter resolution and intravenous contrast. CT angiography was considered positive when an arterial stenosis secondary to external compression was seen with hyperabduction of the upper extremity.
Results: Five of the six CT angiograms were positive. Adequate abduction of the arm in the sixth patient was not achieved due to complaints of pain resulting in an incomplete study. With mean follow-up of 9.4 months, 95% (n=19) of patients with a positive hyperabduction test on physical examination were free of symptoms post-operatively. 100% of patients with a positive arterial duplex (n=8) were free of symptoms as were 50% (n=2) of those with a positive magnetic resonance arteriogram. All patients with a positive CT angiogram, with their neurovascular compression localized to the thoracic outlet, had successful operative decompression. Operative complications did not lead to any long term sequelae. The operative complications included a pneumothorax rate of 30% (n=13), dysthesias 26% (n=11), sympathetic dystrophy 5% (n=2), and a transient long thoracic nerve palsy 2% (n=1).
Conclusions: For patients with neurogenic thoracic outlet syndrome, CT angiogram with abduction of the arm can be used as an adjunct to confirm the diagnosis by both identifying and localizing the region of neurovascular compression. A positive CT angiogram then correlates with successful operative decompression.