Signs of Basilar Skull Fracture in an Infant
In infants with suspected basilar skull fracture, look for hemotympanum (blood behind the eardrum), bleeding from the ear canal, periorbital ecchymosis (raccoon eyes), and postauricular ecchymosis (Battle's sign), though these classic signs may be delayed or absent in the acute setting. 1, 2
Clinical Presentation
Early Physical Findings (Most Common)
- Hemotympanum is the most frequent finding, present in approximately 58% of pediatric basilar skull fractures 2
- Bleeding from the ear canal occurs in about 47% of cases 2
- Cerebrospinal fluid otorrhea (clear fluid draining from ear) is seen in approximately 26% of patients 2
- Cerebrospinal fluid rhinorrhea (clear fluid from nose) is less common, occurring in only about 2% of cases 2
Late Physical Findings (Delayed 12-48 Hours)
- Periorbital ecchymosis ("raccoon eyes") - bruising around both eyes 1, 3
- Postauricular ecchymosis (Battle's sign) - bruising behind the ear over the mastoid process 3
- Facial nerve paralysis occurs in approximately 13% of pediatric cases 2
Critical Clinical Context
Diagnostic Limitations
The classic late signs (raccoon eyes and Battle's sign) have poor diagnostic accuracy with low specificity (30.5-52.8%) and positive predictive value (25.7-27.1%) for confirming basilar skull fracture. 3 These signs should not be relied upon to rule in or rule out the diagnosis, but their presence indicates severe head trauma requiring immediate imaging. 3
Risk Stratification Impact
According to the American College of Radiology's PECARN criteria, any signs of basilar skull fracture automatically place an infant in the "high-risk" category regardless of Glasgow Coma Scale score, with approximately 4.4% risk of clinically important traumatic brain injury. 1, 4 This mandates immediate CT head imaging. 1, 4, 5
Associated Findings to Assess
- Altered mental status (irritability, lethargy, not acting normally per parents) 1
- Palpable skull fracture on gentle palpation 1
- Hearing loss complaints (present in 34% of pediatric cases) 2
- Vestibular symptoms are rare in infants 2
Immediate Management Implications
Imaging Requirements
- Non-contrast CT head is mandatory for any infant with suspected basilar skull fracture signs 1, 4, 5
- CT angiography should be strongly considered as basilar skull fractures carry high risk for traumatic arterial dissection 5
- Plain skull radiographs are inadequate as they miss up to 50% of intracranial injuries 1, 5
Common Pitfalls
- Do not wait for late signs (raccoon eyes, Battle's sign) to develop before imaging, as early signs like hemotympanum are more reliable 2, 3
- Do not dismiss the diagnosis based on absence of classic signs, as 37% of basilar skull fractures are not confirmed by initial radiographic findings 2
- Consider non-accidental trauma in infants with basilar skull fracture, especially with inconsistent history or unexplained mechanism 1, 4
- Beware of mimics: Raccoon eyes can rarely indicate neuroblastoma, multiple myeloma, or other systemic diseases rather than trauma 6
Disposition
All infants with signs of basilar skull fracture require hospital admission for close neurological observation with serial examinations, even if initial Glasgow Coma Scale is 15. 4, 5