Neuroimaging in adult penetrating brain injury: a guide for radiographers

Abstract

Penetrating brain injuries (PBI) are a medical emergency, often resulting in complex damage and high mortality rates. Neuroimaging is essential to evaluate the location and extent of injuries, and to manage them accordingly. Currently, a myriad of imaging modalities are included in the diagnostic workup for adult PBI, including skull radiography, computed tomography (CT), magnetic resonance imaging (MRI) and angiography, with each modality providing their own particular benefits. This literature review explores the current modalities available for investigating PBI and aims to assist in decision making for the appropriate use of diagnostic imaging when presented with an adult PBI. Based on the current literature, the authors have developed an imaging pathway for adult penetrating brain injury that functions as both a learning tool and reference guide for radiographers and other health professionals. Currently, CT is recommended as the imaging modality of choice for the initial assessment of PBI patients, while MRI is important in the sub-acute setting where it aids prognosis prediction and rehabilitation planning, Additional follow-up imaging, such as angiography, should be dependent upon clinical findings.

Keywords: Angiography; computed tomography; magnetic resonance imaging; penetrating brain injuries.

Figure 1

(a) AP skull radiograph showing three metal nails. (b) Axial non-contrast CT of the same patient. Note the metallic artefact.

Figure 2

Wooden penetrating foreign body, (a) Axial non-contrast CT; (b) Axial spin-echo Tl-weighted MRI; (c) Axial fast-spin echo T2-weighted MR and (d) SWI imaging of the same patient. A wooden object has passed through the orbit, into the parieto-occipital region, abutting the inner aspect of the skull. Note the application of SWI imaging to demonstrate the tract. MRI, magnetic resonance imaging; SWI, susceptibility-weighted imaging.

Figure 3

Self-inflicted nail-gun injury to the head. Anterior (a) and lateral (b) right internal carotid angiograms demonstrating focal narrowing of the right internal carotid artery as it runs adjacent to the nail with no extravasation. The nail appears to be causing some focal pressure or vasospasm on the artery at the level of the foramen lacerum with no perforation.

Figure 4

Diagnostic imaging pathway for adult patient with penetrating brain injury. GCS, Glasgow Coma Scale.