- •
Penetrating thoracic trauma encompasses a wide variety of injuries.
- •
The role of imaging in evaluating these patients will be determined by hemodynamic stability, mechanism of injury, and location of injury.
- •
Although most injuries will be to the lungs and pleura and may only be evaluated with serial radiographs, multi-detector computed tomography is being used with increasing frequency in hemodynamically stable patients.
- •
With an understanding of injury mechanics and trajectory, the radiologist can
Penetrating Thoracic Injury
Section snippets
Key points
Mechanism
Penetrating trauma can be divided into ballistic and nonballistic injuries. The mechanism of injury from nonballistic injuries (ie, stab and puncture wounds) is more intuitive than the mechanism for injury from ballistic trauma. Nonballistic penetrating injuries are caused by tissue disruption and laceration along their trajectory; determining that trajectory on imaging can help identify the injuries it has caused.
Ballistic trauma is a more complex topic; but in the least, a basic understanding
Imaging
Penetrating thoracic trauma encompasses a heterogeneous group of injuries with differing presentations. Most penetrating injuries involve only the chest wall and lung parenchyma14, 15 and may initially be imaged with chest radiography (CXR). Entry and exit wounds should be demarcated by radiopaque markers (a paper clip can be used) to help approximate the injury trajectory and its proximity to the mediastinum. Penetrating nonmediastinal thoracic trauma is historically treated conservatively
Penetrating mediastinal injury
Most patients with thoracic trauma can be treated conservatively; the exception is the subset of patients with penetrating trauma to the mediastinum.17 Transmediastinal penetrating injury is defined as penetrating injury that traverses any part of the mediastinum and by its nature can involve any of the sensitive structures it contains, such as the heart, great vessels, trachea and bronchi, and the esophagus.
These patients have high operative and mortality rates.2, 14, 17, 20, 21, 22, 23, 27
Pulmonary Contusion
Pulmonary contusions are frequently encountered after penetrating chest injuries. Histologically contusions are a result of disruption of the alveolar-capillary membrane and small blood vessels leading to the subsequent filling of the alveoli and interstitium with hemorrhage or fluid.32 Contusions appear as fluffy air-space, nonsegmental opacities that do not respect the pleural boundaries. Typically they occur close to the chest wall in the periphery of the lung demonstrating a 2- to 3-mm area
Pneumothorax
Another common sequela of penetrating trauma is the formation of a pneumothorax. Pneumothoraces can form directly from the penetrating trauma itself or from a leak in the airway. On both CXR and CT, a pneumothorax appears as an air-filled pleural space, devoid of lung markings, surrounding the thin visceral pleura of the lung (Fig. 19). On an erect or semierect CXR, a pneumothorax will most commonly be seen along the apicolateral aspect of the hemithorax.35 They can be overlooked on the initial
Chest wall
The initial CXR may not accurately demonstrate the extent of trauma to the chest wall. The bones of the thorax are frequently injured with penetrating injuries. Rib fractures can injure intercostal vessels, bleed themselves, or tear the chest wall musculature.40 Fractures of the first 3 ribs may be associated with neurovascular and tracheobronchial injuries. Fractures of the lower 3 ribs are associated with diaphragmatic and abdominal organ injuries (particularly liver, spleen, and kidneys).
Diaphragmatic injuries
Diaphragmatic injuries (DI) are often subtle on imaging. The missed diagnosis of a DI can lead to herniation and subsequent strangulation of the herniated viscus even years after the initial injury. In cases of penetrating thoracoabdominal trauma, one must maintain a heightened awareness to the possibility of a DI. Penetrating injuries to the diaphragm usually result in a short defect, 1 to 2 cm in length, and without evisceration.12, 41, 42 One should look closely for small fat-containing
Summary
Penetrating thoracic trauma encompasses a wide variety of injuries. The role of imaging in evaluating these patients will be determined by hemodynamic stability, mechanism of injury, and location of injury. Although most injuries will be to the lungs and pleura and may only be evaluated with serial radiographs, MDCT is being used with increasing frequency in hemodynamically stable patients. With an understanding of injury mechanics and trajectory, the radiologist can play a vital role in
References (47)
- et al.
Penetrating thoracic trauma
Semin Thorac Cardiovasc Surg
(2008) - et al.
Wound ballistics of firearm-related injuries—part 1: missile characteristics and mechanisms of soft tissue wounding
Int J Oral Maxillofac Surg
(2014) - et al.
The selective conservative management of penetrating thoracic trauma is still appropriate in the current era
Injury
(2015) - et al.
Triage and outcome of patients with mediastinal penetrating trauma
Ann Thorac Surg
(2007) - et al.
Transmediastinal gunshot wounds in a mature trauma centre: changing perspectives
Injury
(2013) - et al.
Great vessel and cardiac trauma: diagnostic and management strategies
Semin Thorac Cardiovasc Surg
(2008) - et al.
Penetrating cardiac injury: overcoming the limits set by nature
Injury
(2009) Esophageal trauma
Semin Thorac Cardiovasc Surg
(2008)- et al.
Traumatic lung herniation
Ann Thorac Surg
(1997) - et al.
Imaging of penetrating chest trauma
Radiol Clin North Am
(2006)
CT detection of occult pneumothorax in multiple trauma patients
J Emerg Med
Chest wall, lung, and pleural space trauma
Radiol Clin North Am
Sinus cut-off sign: a helpful sign in the CT diagnosis of diaphragmatic rupture associated with pleural effusion
Eur J Radiol
Blunt polytrauma: evaluation with 64-section whole-body CT angiography
RadioGraphics
Imaging patients with cardiac trauma
RadioGraphics
Acute traumatic aortic injury: imaging evaluation and management
Radiology
Historical overview of wound ballistics research
Forensic Sci Med Pathol
The early hospital management of gunshot wounds. Part 1: head, neck, and thorax
Trauma
The role of computed tomography in terminal ballistic analysis
Int J Legal Med
Kidney in danger: CT findings of blunt and penetrating renal trauma
RadioGraphics
Penetrating wounds to the torso: evaluation with triple-contrast multidetector CT
RadioGraphics
Cited by (23)
Abdominal Aorta Bullet Embolism: Presentation and Management
2021, Annals of Vascular SurgeryCitation Excerpt :Additionally, access to hospital resources like bypass capabilities, transfusion protocols, and availability of surgical staff play a role in survival.10 Death is commonly secondary to cardiac tamponade or hemorrhage.12 Patients with PCI may demonstrate any combination of Beck's triad with hypotension, jugular venous distention, and muffled heart sounds on auscultation suggesting pericardial effusion or tamponade.13
Tubular Opacity in the Lung Along a Bullet Trajectory
2021, Archivos de BronconeumologiaThoracic Trauma
2021, Cohen's Comprehensive Thoracic AnesthesiaImaging in trauma in limited-resource settings: A literature review
2019, African Journal of Emergency MedicineCitation Excerpt :It is important to note that patients with penetrating injury to the mediastinum have high morbidity and mortality. “The growing data suggest that a combination of echocardiography and multi-detector CT can be used to effectively screen these patients and preclude the need for a more invasive work-up” [9]. However, in the absence of CT scan, ultrasound to evaluate for free fluid, combined with LODOX/Statscan to determine the possible trajectory of penetrating ballistics may be useful when combined with serial exams and trending of lab studies.
Occult lawn mower projectile injury presenting with hemoptysis
2017, Radiology Case ReportsThe clinical implications of severe low rib fracture in the management of diaphragm injury: A Case Control Study
2017, International Journal of Surgery
The authors have nothing to disclose.