Abstract and Introduction
Abstract
A variety of head and neck vascular emergencies, such as nosebleeds or neoplastic hemorrhages, can occur spontaneously or result from blunt or penetrating trauma. As most traumatic venous bleeding can be resolved with direct pressure, the main focus is on arterial injury. The role of catheter angiography in the acute trauma setting has shifted over the past 15 years, with the concomitant advances in computed tomography (CT) angiography for diagnosis, and development of microcatheters and embolic agents for therapy.
Introduction
A variety of head and neck vascular emergencies, such as nosebleeds or neoplastic hemorrhages, can occur spontaneously or result from blunt or penetrating trauma. As most traumatic venous bleeding can be resolved with direct pressure, the main focus is on arterial injury. The role of catheter angiography in the acute trauma setting has shifted over the past 15 years, with the concomitant advances in computed tomography (CT) angiography for diagnosis, and development of microcatheters and embolic agents for therapy.
Regional trauma associations have proposed algorithms for which patients should be evaluated by CT angiography and/or catheter angiography for traumatic head and neck vascular injuries.[1–3] These include high-risk mechanisms such as: high-energy collisions, neck hyperextension injury, intra-oral trauma, and near-hanging with anoxic brain injury. Additionally, CT or catheter angiography should be considered in patients with LeFort/midface fractures, cervical spine or basilar skull fractures, diffuse axonal injury with Glasgow Coma Scale (GCS) < 6, a new focal neurological deficit, neurological examination incongruous with head CT findings, or imaging evidence of a new cerebral infarct in the setting of trauma.
Clinically occult head and neck vascular injury is rare; however, aggressive CT screening in asymptomatic patients has become commonplace given the potentially devastating sequelae of a missed diagnosis,[4–6] combined with ease of access to CT angiography. Ongoing discussion in the trauma community continues regarding patient selection criteria, given the concerns of cost effectiveness of broad screening in asymptomatic patients as well as minimizing unnecessary radiation exposure.
There remain cases in which conventional angiogram remains the 'gold standard.' These include CT angiograms limited by artifact from dental implants/amalgam, from metal or shrapnel, situations where appropriate bolus timing cannot be achieved, and hemodynamically unstable patients with a high probability of requiring endovascular intervention. Diagnostic catheter angiogram should always be considered in a patient with high suspicion for cervical vascular injury in the setting of a normal CT angiogram, as this is a dynamic disease process and contrast opacification of a vessel on cross-sectional imaging may not fully reflect flow dynamics and collateral pathways.
Appl Radiol. 2012;41(3):10-16. © 2012 Anderson Publishing, Ltd.
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