Traumatic contusion and subarachnoid hemorrhage

Clinical:

• A 46 years old man
• Involved in motor vehicle accident
• History of loss of consciousness
• Complains of headache and persitent vomiting
• Clinical assessment in ED shows GCS 15/15, no neurological deficit

CT findings:

• There are multiple hyperdense foci at left frontal and temporal lobe (yellow arrows).
• The hyperdensities are of various sizes with minimal surrounding hypodensities.
• There are hyperdensities along the cerebral sulci at left frontoparietal region (red arrow)
• There is associated effacement of the cerebral sulci.
• No midline shift, no internal brain herniation

Diagnosis: Traumatic brain injuries (cerebral contusion and subarachnoid hemorrhage)

Discussion:

• Cerebral contusion also known as brain bruise occurs due to closed head injury against inner surfaces of the skull at the time of impact
• Usually at contrecoup site of the injury
• Location of cerebral contusion is at anterior base frontal, temporal lobes
• CT appearance show small, focal areas of petechial haemorrhage, peripherally located, multiple and can be bilateral. However CT scan can be normal, very subtle and/or odema on initial imaging. Over time, about half of the contusions evolve and grow larger in size.
• Traumatic subarachnoid hemorrhage (SAH) occurs in about 40% of patients with moderate to severe head injury is associated with a significant worse outcome
• Nearly all cases of traumatic SAH have other lesions to suggest traumatic cause
• CT findings of SAH is seen as linear areas of hyperdensities in the cerebral sulci and convexities, Sylvian fissures or basilar cisterns. Subtle SAH can be seen at interpeduncular fossa.