Interventional radiology in the civilian neurotrauma setting

Abstract

Civilian trauma injuries in the United States monitored by the Centers for Disease Control (CDC) resulted in 41 million emergency room-related trauma visits annually [1], with approximately 34,000 motor vehicle traffic-related deaths [2] and 30,000 deaths related to unintentional falls [2]. From these accidents, the incidence of non-penetrating carotid injury is estimated between 0.08 and 0.67 % in major trauma centers [3-5]. Typically, these types of injuries are observed in the younger population [4] with motor vehicle accidents accounting for 80 % of these injuries [6]. Injuries to the carotid or vertebral artery generally remain clinically silent, however if left untreated, there exists a stroke rate of up to 21 % [7] with an associated mortality of 20-40 % [8]. Over the years, the treatment paradigm for vascular injuries to the head and neck have changed in concert with technological advances. For example, radical exploratory neck dissections have been supplanted by emergency room computer tomography (CT) using high resolution vascular imaging modalities to evaluate the degree of injury. Along with CT and magnetic resonance (MR) angiography, there have also been significant advances in endovascular approaches for treating vascular injuries to the head and neck. An analysis of the National Trauma Data Bank, showed a 27-fold increase of endovascular utilization in the early twenty-first century [9]. Prior to these imaging developments, surgical exploration of the neck and the vessels was the standard of care [10, 11]. Currently, the majority of vascular injuries involve the aortic arch in the chest, the carotid, and vertebral arteries in the neck, and the intracranial cerebral vasculature. The most common cause for injury to the great vessels branching off the aortic arch occurs with motor vehicle accidents, most often associated with wearing a shoulder belt [12]. The mechanism of injury to the great vessels comes from the shear force of the kinetic energy translating into potential energy that is absorbed by the vessels. Other blood vessel injuries of the head and neck, such as, carotid artery dissection, occur when the vessel is injured during hyperflexion/extension movements. As for the head, pseudoaneurysm formation is more common in locations where the cerebral vessels are adjacent to the falx (Fig. 10.1). In this chapter, we will review relevant vascular anatomy, imaging techniques, and discuss management options for associated vascular injuries. Fig. 10.1 Motor vehicle crash causing a traumatic intracranial pseudoaneurysm from shear of the anterior cerebral artery (ACA) against the falx: 32 year old woman who presented as a restrained driver in a motor vehicle crash. a Routine workup in the emergency department disclosed a 7 mm hyperdense right frontal lesion adjacent to the falx. b MR imaging subsequent to the CT demonstrated an associated flow void with confirmation of an unruptured traumatic pseudoaneurysm of the ACA on MR angiography (c). This right distal A2 segment of the anterior cerebral artery pseudoaneurysm measured 13.8 mm × 5.7 mm (d) and was treated uneventfully with coil embolization (e).