A prospective validation of a current practice: the detection of extremity vascular injury with CT angiography

Arteriography is the current "gold standard" for the detection of extremity vascular injuries. Less invasive than operative exploration, conventional arteriography (CA) still has a 1% to 3% risk of morbidity and may delay definitive repair. Recent improvements in computed tomography (CT) technology has since broadened the application of CT to include the diagnosis of cervical, thoracic, and now extremity vascular injury. We hypothesized that CT angiography (CTA) provides equivalent injury detection compared with the more invasive CA, but is more rapidly completed and more cost effective.

A prospective evaluation of patients, ages 18 to 50, with potential extremity vascular injuries was performed during 2006-2007. Ankle-brachial indices (ABI) of injured extremities were measured on presentation in all patients without hard signs of vascular injury. Patients whose injured extremity ABI was <0.9 were enrolled and underwent CTA followed by either CA or operative exploration if CTA findings were limb threatening. Interventionalists were blinded to CTA findings before performing and reading CAs.

Twenty-one patients (mean age, 26.1 +/- 7.1 years) had 22 extremity CTAs after gunshot (82%), stab (9%), or pedestrian struck by automobile (9%) injuries to either upper (32%) or lower (68%) extremities. Eleven of 22 (50%) extremities had associated orthopedic injuries while the mean ABI of the study population was 0.72 +/- 0.21. Twenty-one of 22 (96%) CTAs were diagnostic and all CTAs were confirmed by either CA alone (n = 18), operative exploration (n = 2), or both CA and operative exploration (n = 2). Diagnostic CTAs had 100% sensitivity and specificity for clinically relevant vascular injury detection. Unlike rapidly obtained CTA, CA required 131 +/- 61 minutes (mean +/- SD) to complete. In our center, CTA saves $12,922 in patient charges and $1,166 in hospital costs per extremity when compared with CA.

With acceptable injury detection, rapid availability, and a favorable cost profile, our results suggest that CTA may replace CA as the diagnostic study of choice for vascular injuries of the extremities.