For a patient with head trauma and soft‑tissue swelling, when is emergent non‑contrast head CT indicated and how should the swelling and any associated skull fracture or intracranial injury be managed?

Head Trauma with Soft-Tissue Swelling: Diagnostic Imaging and Management

Emergent non-contrast head CT is indicated for any patient with head trauma and soft-tissue swelling who meets clinical decision rule criteria, including loss of consciousness, post-traumatic amnesia, age >60 years, vomiting, focal neurologic deficits, GCS <15, coagulopathy, or dangerous mechanism of injury. 1, 2

When to Order Emergent CT Imaging

High-Risk Indicators Requiring Immediate CT

• Progressive neurologic deterioration or declining GCS (e.g., from 15 to ≤8) mandates immediate non-contrast head CT 1
• Initial loss of consciousness with any of the following: headache, vomiting, age >60 years, drug/alcohol intoxication, short-term memory deficits, physical trauma above the clavicles, post-traumatic seizure, GCS <15, focal neurologic deficit, or coagulopathy 2
• Moderate to severe head trauma (GCS 9-12 or GCS 3-8) always requires emergent non-contrast head CT regardless of soft-tissue findings 1, 2

Soft-Tissue Swelling as an Isolated Finding

• In infants <1 year with soft-tissue swelling >5 cm, CT head examination is justified as skull fractures were found in 58% and intracranial hemorrhage in 2.6% of cases 3
• Soft-tissue swelling alone (without other high-risk features) in children presenting in delayed fashion (>24 hours post-injury) may warrant CT primarily for non-accidental trauma evaluation, though neurosurgical intervention is rarely required 4
• Peri-orbital soft-tissue swelling, hyphema, vision loss, or extraocular restriction suggests orbital injury requiring thin-section orbital CT with multiplanar reconstructions 5

Imaging Protocol

CT is the Gold Standard for Acute Evaluation

• Non-contrast head CT is the definitive initial imaging modality, rapidly detecting hemorrhage, herniation, hydrocephalus, and skull fractures with high sensitivity 1, 5
• Contrast is not indicated in the acute trauma setting for detection of skull fractures or intracranial hemorrhage 5
• Multiplanar reconstructions improve detection of subtle skull base and facial fractures 5

When MRI is NOT Appropriate

• MRI is inappropriate for initial evaluation of acute head trauma with declining mental status—it takes too long and patients are often too unstable 1, 6
• MRI is reserved for subacute/chronic evaluation (>7 days) when persistent symptoms require assessment for subtle white matter injury, microbleeds, or chronic sequelae not visible on CT 5, 2

Management of Skull Fractures and Intracranial Injury

Immediate Critical Care Measures

• Maintain airway protection, notify neurosurgery immediately, elevate head of bed to 30 degrees, and avoid hypotension in patients with acute head trauma and declining mental status 1
• Linear/non-displaced skull fractures with associated extra-axial hemorrhage (epidural or subdural hematoma) are the most common findings in delayed presentations with scalp swelling (40% of cases) 4

Admission vs. Discharge Criteria

• Patients with skull fractures but non-focal neurologic exams may be discharged from the emergency department if no intracranial injury is present 4
• Admission for neurologic monitoring is warranted when intracranial hemorrhage is present, even if small, or when GCS is abnormal 4
• No patient with isolated soft-tissue swelling and skull fracture (without intracranial injury) required surgical intervention in pediatric studies 4

Associated Injuries to Evaluate

Concomitant Injuries are Common

• 68% of facial fracture patients have associated head injury, necessitating concurrent head CT evaluation 5
• Cervical spine injuries occur in 6-19% of patients with significant maxillofacial trauma, with higher rates in severe injuries 5
• Orbital apex and carotid canal involvement may occur with Le Fort III fractures, requiring vascular imaging if clinically suspected 5

Common Pitfalls to Avoid

• Do not delay imaging for "medical stabilization" in patients with declining mental status—this worsens outcomes 1
• Do not attribute declining consciousness to drugs or metabolic causes when clear trauma history with high-risk features exists 1
• Do not order MRI first in acute trauma—this wastes precious time when CT is the appropriate study 1, 6
• Do not assume small soft-tissue swelling is benign in infants <1 year, as significant intracranial injury can occur with minimal external findings 3
• Do not forget to evaluate for non-accidental trauma in young children presenting with scalp swelling, particularly in delayed fashion 4