A review of penetrating brain trauma: epidemiology, pathophysiology, imaging assessment, complications, and treatment

Gunshot injuries are the most common cause of penetrating brain injury (PBI) and carry a high morbidity and mortality. The incidence of PBI has increased over the last decade with an estimated 35,000 civilian deaths annually. Patients that survive to reach the hospital require rapid triage and imaging evaluation. CT findings in conjunction with the Glasgow Coma Scale are typically used to determine which patients are surgical candidates. Radiologists should be familiar with the various injury patterns and imaging findings which are poor prognostic indicators, notably brainstem, bilateral hemispheric, multilobar, or transventricular injuries. Post-traumatic complications, including intracranial infections, cerebrospinal fluid leaks, traumatic intracranial aneurysms, intraventricular hemorrhage, dural venous sinus thrombus, and bullet fragment migration, also have specific imaging features and serious treatment implications. In this article, we review the initial imaging evaluation of penetrating brain injury using computed tomography with and without angiography. We also describe the imaging features of various post-traumatic complications and their treatment implications. Finally, we discuss the clinical and imaging parameters that serve as important prognostic indicators and the surgical management.