Conventional and Computed Tomographic Arteriography in Penetrating Vascular Injuries

Imaging for Penetrating Vascular Injuries of the Neck

CT angiography can be used in place of catheter-based angiography for penetrating vascular injuries in the neck, excluding patients who should typically undergo immediate surgical exploration. In the absence of hard signs of vascular injury, the physical examination alone is unreliable for excluding an arterial injury. Numerous reports have described delayed neurologic deficits from pseudoaneurysms or other arterial wounding patterns that were not initially identified following penetrating injury. Imaging, therefore, is an important component of the thorough evaluation of patients with penetrating trauma to the neck.

Catheter-based angiography has proved sensitive and specific for arterial injury in the neck. Despite this, stab wounds in asymptomatic patients do not seem to warrant routine arteriography owing to a very low rate of detection of significant vascular injury; gunshot wounds are more likely to result in positive findings leading to surgical intervention. Symptoms (e.g., hematoma, swelling, altered mental status) result in higher rates of detection of arterial injury with angiography. The cost-effectiveness of catheter-based angiography was evaluated in 111 patients with penetrating neck trauma. The cost was $3 million per central nervous system (CNS) event prevented, leading some to believe that angiography in the neck should be largely abandoned in favor of less expensive and less invasive imaging such as ultrasound or CT.

CT has emerged as a very important imaging modality for penetrating neck trauma. Its utility lies in part in the evaluation of aerodigestive tract injury, although these injuries have a higher false-positive rate than vascular injuries, in which the sensitivity and specificity for arterial injuries are both greater than 95%. Metal artifacts from ballistic injury limit the utility of CT in some patients. CT has been demonstrated to accompany decreased rates of unnecessary neck exploration and limits the need for oesophagogram or catheter-based arteriogram. If CT demonstrates ballistic trajectories that are remote from important structures then additional invasive imaging can be avoided. CTA is also a useful for preoperative planning when the patient’s stability permits and there is need for clarification of the best surgical approach ( Figures 1 and 2 ).