hemicraniectomy

Hemicraniectomy

Decompressive craniectomy of one side.

Hemicraniectomy is a decompressive surgery used to remove a large bone flap to allow edematous brain tissue to bulge extracranially.

Decompressive hemicraniectomy (DC) and duroplasty after malignant brain infarction or traumatic brain injury is a common surgical procedure. Usually, preserved bone flaps are being reimplanted after the resolution of brain swelling. Alloplast cranioplasties are seldom directly implanted due to the risk of wound healing disorders.

see Decompressive craniectomy for intracerebral hemorrhage.

see Decompressive craniectomy for malignant middle cerebral artery territory infarction.

see Decompressive craniectomy for severe traumatic brain injury.

1. Some prefer the use of a Mayfield skull clamp placed low

to give greater access 1)

(not feasible with severely comminuted skull fractures)

2. AP axis of the head is placed horizontal to floor (unless C-spine not cleared or if neck too immobile one may compensate for this by rotating table)

Two options

a)

A starts at widow ’speak, similar to trauma flap, but with increased exposure by taking it posteriorly close to the inion, then turning sharply anteriorly and hugging the ear to preserve blood supply

b)

“T” incision. Less risk of flap ischemia.The“T” joins the midline incision behind the coronal suture to preserve the STA 2).

A burr hole is made just above the posterior root of the zygomatic arch, a second one may be made just behind the frontal insertion of the zygomatic arch, inferior to the superior temporal line

Bone flap: proceed posteriorly from the posterior zygomatic arch using the foot plated craniotome. Posteriorly, stay ≈ 1 cm superior to asterion to avoid the transverse sinus. The flap is taken 1 cm beyond the lambdoid suture, and then up towards the sagittal suture, crossing the lambdoid suture again (this leaves a small amount of bone posteriorly on which the head can rest post-op). An anterior turn is made 1 cm short of the sagittal suture to avoid the superior sagittal sinus, and the sagittal suture is paralleled. The coronal suture is crossed and the drill is taken as low as possible in the anterior cranial fossa near the midline. Staying as low as possible, the orbital roof is followed posteriorly towards the second burr hole. The burr holes are then connected

e) some bone may need to be rongeured to expose the floor of the middle fossa

Based on inferiorly, taken to 1 cm short of the craniotomy edge. Dural releasing incisions may be made at intervals up to the bone margin to avoid strangulation of the brain on the dural edge

● Onlay: 2 cm wide strips of dural substitute can then be placed partway under the dural edge around the periphery to isolate the brain from the undersurface of the skin flap where there will be a gap in the dura

● some authors suture a dural graft in place the dural flap is then replaced on top of the brain and dural substitute strips, and is not sutured.

Hemicraniectomy with a diameter of ≤10 cm, especially in combination with sharp trepanation edges, has been associated with an increased incidence of shearing injury to the herniated brain 3).

see Hydrocephalus after decompressive craniectomy.


1) , 2)
Holland M, Nakaji P. Craniectomy: Surgical indications and technique. Operative Techniques in Neurosurgery. 2004; 7:10–15
3)
Wagner S, Schnippering H, Aschoff A, Koziol JA, Schwab S, Steiner T. Suboptimum hemicraniectomy as a cause of additional cerebral lesions in patients with malignant infarction of the middle cerebral artery. J Neurosurg.2001;94:693–696
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  • Last modified: 2019/10/27 12:40
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