Keywords
vertex epidural hematoma - traumatic brain injury - craniotomy
Palavras-chave
hematoma epidural do vértex - traumatismos craniocerebrais - craniotomia
Introduction
Vertex epidural hematomas (VEHs) are extremely rare. They comprise ∼ 1 to 8% of all
traumatic epidural hematomas.[1] The diagnosis is difficult, and it is based on cases of inadequacy of orientation
in axial head CT scans; therefore, the identification of this type of hematoma is
challenging.[2]
[3] In many cases, the superior sagittal sinus (SSS) is the main structure involved
in the origin of the bleeding.[4]
There are a lot of reported cases of VEH.[1]
[5]
[6]
[7] We describe in the present article a rare and extremely large VEH with central brain
herniation, and provide a technical note on the surgical planning and treatment.
Case Report
A 34-year-old male patient was admitted to our hospital after a traumatic aggression
on the left superior parietal region by a Wood stick during a discussion. He immediately
lost his consciousness, and was intubated and transferred by helicopter to our facility.
After 80 minutes, upon admission at the emergency room, a physical examination revealed
a dilated left pupil with no reaction to light. He had a Glasgow coma scale (GCS)
score of 6 and a subcutaneous hematoma on the vertex scalp. The best motor response
was obtained in the arms, which made us investigate traumatic spinal cord injury.
Clinically, he presented arterial pressure of 140/95 mmHg, heart rate of 88 beats/minute,
and blood oxygen level (SpO2) of 98%, and received 2,000 mL of crystalloid fluid. A non-contrast brain computed
tomography (CT) scan showed a large epidural hematoma on the vertex between the coronal
e lambdoid sutures, bilaterally ([Fig. 1]). The volume of the hematoma was of approximately 146 mL. A three-dimensional (3D)
CT reconstruction revealed a straight fracture over the sagittal suture extending
to the frontal bone ([Fig. 2]). No spinal fracture or dislocation was found on the routine CT of the spine. Due
to the evident brain herniation in progress and intracranial hypertension, the patient
was transferred immediately to the operating room without being submitted to a more
accurate study of the vascular damage in the SSS
Fig. 1 Large vertex epidural hematoma with central brain herniation and compression of the
diencephalic structures. (A) Coronal and (B) sagittal computed tomography (CT) scan sequences.
Fig. 2 (A) Intraoperative view of a diastatic fracture of the sagittal suture. (B) After the biparietal craniotomy with visualization of a large epidural hematoma;
(C) Coronal CT scan one day after surgery.
Surgical procedure: The patient was placed in supine position with a slight flexion of the head. An
incision was planned bilaterally at a point between the coronal and lambdoid sutures.
After a subperiosteal plane dissection, the parietal bone was exposed, showing a diastatic
fracture aligned with the sagittal suture ([Fig. 2]). A large bilateral parietal bone flap was made by two anterior burr holes, close
to the coronal suture, and close to the midline. The flap was taken out, and the clot
was identified and evacuated carefully from the lateral to the medial parts to prevent
bleeding from the SSS. There was no injury in the outer surface of the SSS. Dural
anchoring sutures were applied around the lateral edges of the craniotomy. The subdural
space was inspected to exclude the presence of subdural hematoma, and, at the same
time, we inserted saline solution to facilitate dural adhesion to the bone. The flap
was secured with sutures, and subgaleal drains were placed.
Postoperative Course
Recovery was good, with a GCS score of 15 after 24h. A CT scan of the head after surgery
showed a good result and no evidence of mass effect, with minimal residual hematoma
([Fig. 2]). By day 5, the patient was discharged successfully, with no additional deficits.
Discussion
Vertex epidural hematomas are rare and frequently associated to bleeding from the
venous sinus, bone fracture or dural diffuse bleeding (arterioles).[7] They must be considered a special clinical entity because of their presentation
and vascular etiology.[1] Clinical suspicion relies on the symptoms of the patient and on the mechanism of
the injury. In cases in which the SSS is damaged, the clinical course is more acute,
with elevation of intracranial pressure (ICP) and brain herniation.[7]
[8] When the bleeding comes from other sources, the clinical symptoms and the evolution
are more indolent.
A wide variety of symptoms can occur in cases of VEH. In the emergency room, weakness
in the lower extremities can lead the physicians to mistake the clinical picture for
spinal cord injury. In cases of paraplegia after a traumatic brain injury, the possibility
of occurrence of VEHs must be considered. If the patient is conscious, awake, a critical
volume of 40 to 50 mL can be treated conservatively.[9] About 30% of VEHs reported have a chronic course of symptoms. The block of the cerebrospinal
fluid and disruption of the venous drainage can explain the chronic presentation,
even with VEHs with small volumes.[10]
Due to its location, VEH can cause compression of the rolandic cortex, with special
involvement of the motor control of the lower limbs.[5] This presentation is usually noted when the course of the hematoma expansion is
more subtle and slow. Even if it is secondary to venous structures, VEH can present
a large and quick expansion and be restrained by the coronal and lambdoid sutures.
In this situation, a pressure vector toward the diencephalon contributes to the depression
of the consciousness level.
Coronal CT scan sequences are the ideal method to investigate VEHs. Depending on the
orientation of the axis in axial CT scans of the brain, a large VEH may not be visualized,
and be masked by surround bone.[3] This is a particular problem when the patient is studied in sequential (horizontal)
scans instead of spiral (helical) scans, and the more cephalic scan planned be out
of VEH.[2] This interface between these two structures with grossly differing density is known
to be problematic. When the trauma is on the skull vertex and reveals strong forces,
repeating a normal CT scan and finding no evidence of hematoma is a secure option
to identify or rule out VEH.
Some authors recommend the use of CT venous angiography before craniotomy to prevent
a large bleeding from the SSS and thus program a surgical strategy. Cerebral arteriography
has been mentioned as an option in cases of chronic evolution due to the rare possibility
of occurrence of an arteriovenous fistula.[10] Before the existence of the CT, finding a dislocation of the SSS from the inner
skull table was an evidence of VEH.[2] Slow blood flow on the SSS is another evidence. In pediatric patients with open
fontanels, treatment with aspiration by direct puncture is an alternative approach.[2]
Many authors have described surgical techniques in which a bone bridge is left over
the SSS to avoid potential bleeding.[1]
[4] That is a consideration if we realize the risks of dealing with the second third
of the SSS. Tears over the SSS may complicate the surgery and result in higher morbidity
and mortality.[1]
[8] Another option that has been mentioned is the interposition of sutures using Teflon
pledgets to control profuse SSS bleeding.[5] In our case, we planned a straight incision over a line between the coronal and
lambdoid sutures. A biparietal craniotomy was performed with multiples burr holes
beside the sagittal suture. At this point, we didn't see active bleeding coming from
the sinus, and we ended up performing a craniotomy without a bridge bar. In our opinion,
this strategy can be followed carefully before planning the craniotomy, leaving only
a strip of bone over the SSS if active bleeding is visualized under the fractured
bone.
We emphasize in the present article that the use of saline infusion for the expansion
and elevation of dural gaps has some risks that include infections and the creation
of hypertensive subdural collections. Central and peripheral anchoring are still the
main options to prevent the accumulation of a new hematoma. When no anchoring point
is possible to obtain, the direct repair of the SSS bleeding can be performed by direct
pressure with cottonoids, muscle and Gelfoam (Pfizer, New York, NY, US). Even digital
pressure is a temporary option. Putting the head in the reverse Trendelenburg position
helps prevent air embolism. In rare cases with large sinus lacerations, the use of
a Fogarty catheter, sinoraphy with continuous suture, or even grafts can control this
problem.
Conclusion
Neurosurgeons must be prepared to plan a surgical strategy in cases of large VEHs.
Due to their rare frequency and bleeding risks, they represent a challenge in cases
of emergency surgery.