Helical CT is a reliable method for screening patients with blunt chest trauma for vascular and visceral injuries. Thoracic aortic injuries detected by CT examination affect the immediate clinical management and patient triage. This article describes the clinical indications and imaging protocols for helical CT of the chest used to detect aortic injuries, provides a grading system of the range of aortic injuries demonstrated by CT, and discusses the clinical management decisions that should be considered based on the CT grade of the aortic injury.