Bifrontal contusions occur in about 20% of moderate traumatic brain injury cases and are caused by acceleration/deceleration forces pushing the inferior frontal lobes against the irregular skull base. Hemorrhagic swelling of these contusions can disrupt structures involved in behavior control and personality. When these contusions swell, the brain is displaced posteriorly, which can lead to herniation and deterioration of brain stem function. Aggressive surgical resection of the contusions may worsen neurological outcomes, so surgical decompression through bifrontal craniectomy is preferable to prevent rapid herniation in patients with progressive swelling.

1. D R - A B D U L H A F E D
A L H E M Y A R I
Bifrontal contusions

3. are present in about 20% of
cases of moderate TBI with cerebral contusion
and are due to acceleration/deceleration forces
pushing the inferior frontal lobes and temporal
pole against the irregular skull base

4. Hemorrhagic
swelling of these contusions may disrupt
the median forebrain bundle, gyrus rectus, and
anterior hypothalamic nuclei. These structures
are involved in behavior control and are associated
with changes in personality, volition, motivation,
judgment, and social interactions.

5. When
these contusions swell, the brain is displaced
posteriorly
(descending transalar herniation) and
abrupt deterioration because of descent of the
brain stem into the posterior fossa with stretching
and deformity of the small perforating blood vessels
of the basilar artery with risk of death due to
respiratory arrest, sudden coma, and autonomic
changes

6. These lesions are also very often associated
with disturbances of sodium and water
metabolism (e.g. diabetes insipidus or SIADH).
Aggressive surgical resection of these contusions
may worsen the late neurological deficit and
neuropsychological
consequences. Surgical decompression
requires bifrontal decompressive
craniotomy and cutting of the falx and sagittal
sinus on the frontal cranial fossa.

7. This is a major
procedure, caries hemorrhage risk, and requires
delayed cranioplasty 2-3 months later. The risk
of this surgical procedure must, therefore, be balanced
against risk of death due to herniation. The
timing of deterioration is variable, but brain
edema will usually peak around the 5th to the
10th day, with resolution of the swelling after this
time hence observation for up to 2 weeks with
serial CT scanning every 2-3 days is necessary
to exclude progression of the lesions

8. When the
patients are unable to obey commands, are very
restless, or deteriorate, ICP monitoring with
titrated osmotherapy may be an option with
decompression the next stage. Particular problems
are posed by the patient with progressive
swelling, especially posterior shift of the third
ventricle, but preserved capacity to obey commands.

9. For these patients, prophylactic decompressive
bifrontal craniectomy is usually
preferable to the risk of sudden death or permanent
disability that can result from rapid
herniation