Prospective evaluation of multidetector computed tomography for extremity vascular trauma.

BACKGROUND: Multidetector computed tomographic angiography (MDCTA) is increasingly being used for the assessment of extremity vascular injury. However, to date, there are only retrospective series and a single small prospective study evaluating its efficacy. Therefore, the objective of this study was to prospectively evaluate the ability of MDCTA to detect arterial injury in the injured upper and lower extremities.
METHODS: After institutional review board approval, all trauma patients aged 16 years or older admitted to a Level I trauma center who sustained extremity trauma and underwent initial evaluation with a 64-channel MDCTA from March 2009 to June 2010 were prospectively enrolled. The sensitivity and specificity of MDCTA were tested against an aggregate gold standard of operative intervention, conventional angiography, and clinical follow-up.
RESULTS: During the 20-month study period, 635 patients with extremity trauma underwent a structured clinical examination. Hard signs of vascular injury was observed in 5.5% of patients with a 97.1% incidence of clinically significant injury requiring operative intervention. Eighty-three percent of patients had no signs of vascular injury with no missed injuries detected during follow-up. Eighty-nine MDCTAs were performed in the remaining 73 patients (11.5%) with soft signs. The mechanism of injury was penetrating in 69.9% (42 gunshot wound, 5 stab wound, and 4 shotgun). There were 24 positive studies, 23 of which were confirmed at operation (5 brachial artery injuries, 2 radial, 1 ulnar, 1 external iliac, 2 common femoral, 5 proximal superficial femoral, 2 distal superficial femoral, 4 popliteal, and 1 posterior tibial artery injury). A left posterior tibial artery occlusion was managed nonoperatively. There were 58 negative studies with clinical follow-up available in 100%, for a mean of 10.6 days ± 11.7 days (median, 6 days; range, 1-41 days). MDCTA was nondiagnostic in seven patients (9.6%), five secondary to artifact from retained missile fragments (3 shotgun and 2 gunshot wound), and two secondary to technical errors in reformatting. In the absence of artifact, MDCTA achieved 100% sensitivity and 100% specificity in detecting all clinically significant arterial injuries.
CONCLUSIONS: Physical examination is critical in the decision-making process for the injured extremity and can accurately reduce unnecessary imaging. If imaging is required, MDCTA is a sensitive and a specific noninvasive modality for arterial evaluation and may replace conventional angiography as the diagnostic modality of choice for the evaluation of the acutely injured extremity.