From the Guidelines
Fresh blood in the external auditory canal (EAC) is actually a sign of skull base trauma, not a finding that would rule it out. Signs of skull base fracture in a child with head trauma typically include fresh blood in the EAC, hemotympanum (blood behind the eardrum), cerebrospinal fluid otorrhea (fluid leaking from the ear), Battle's sign (bruising over the mastoid process), raccoon eyes (periorbital ecchymosis), cranial nerve palsies, and cerebrospinal fluid rhinorrhea (fluid leaking from the nose) 1. The presence of blood in the EAC suggests a fracture through the temporal bone that has torn the skin lining the ear canal or disrupted vascular structures in that area. This finding should prompt immediate concern for a basilar skull fracture and warrants comprehensive neurological evaluation and appropriate imaging studies such as CT scan to assess the extent of the injury, as recommended by the American College of Radiology Appropriateness Criteria 1. Early recognition of skull base trauma is critical as these injuries can be associated with intracranial complications and may require specialized management. In cases where there are persistent neurologic deficits that remain unexplained after CT, MRI can be a useful supplement to detect a CSF leak from a skull base fracture or to aid in diagnosing the contents that have herniated through a defect in skull base injuries 1.
From the Research
Signs of Skull Base Trauma
The question asks for a sign that is not indicative of skull base trauma in a kid with head trauma. The provided options include fresh blood in the external auditory canal (EAC).
Analysis of Options
- Fresh blood in the EAC is actually a sign of skull base trauma, particularly a fracture of the temporal bone 2, 3.
- Other signs of skull base trauma include cerebrospinal fluid (CSF) leakage, which can manifest as rhinorrhoea or otorrhoea, and can be confirmed with beta 2 transferin or beta trace protein tests 3, 4.
- The presence of CSF leakage is a significant indicator of skull base trauma and increases the risk of meningitis 2, 5.
Conclusion of Analysis
Given the information provided, fresh blood in the EAC is indeed a sign of skull base trauma. Therefore, it is not the correct answer to the question of what is not a sign of skull base trauma.
Possible Answer
Since the question asks for a sign that is not indicative of skull base trauma, and the provided option (fresh blood in EAC) is actually a sign of skull base trauma, it can be inferred that the correct answer is not listed among the provided options. However, based on the information given in the studies, it can be said that:
- The absence of CSF leakage or other specific signs of skull base trauma (such as rhinorrhoea or otorrhoea) might not necessarily indicate the absence of skull base trauma, but rather the absence of certain complications associated with it 4, 6.
- There are no research papers provided that directly answer the question of what is not a sign of skull base trauma.