Evidence for DHC:
Mortality Reduction in Percentages:
Mortality at 12months after malignant MCA infarction. Forest plot presenting risk difference and 95% confidence interval (CI) for a pooled analysis of mortality at 12months from RCTs comparing DC and best medical care:
- Place head in rigid 3-pin fixation
- A large reverse question mark flap is turned to allow access to a large part of the hemicranium.
- Large craniectomy of frontotemporoparietal region
- Avoid frontal air sinus
- Take the inferior bone cut as low as possible to the floor of the middle fossa and ronguer/drill additional bone to accomplish this
- typical craniectomy flap measures at least 15 cm anteroposteriorly and 10 to 12 cm craniocaudal
- dura is opened in a C-shaped or stellate manner
- When the anterior temporal lobe is infarcted and tentorial herniation is present or impending, perform an anterior temporal lobectomy with resection of the uncus and visualization of the tentorial edge, third nerve, and midbrain
- lax duraplasty with autologous pericranial graft, closure must be capacious; be able to pick up and freely slide the lax dural sac
- Muscle reapproximated loosely or not at all
- Scalp is closed in layers (drains optional but preferred)
- parenchymal or subdural ICP monitor optional
- bone flap typically discarded (prefer delayed cranioplasty with a custom implant) or store bone flap in abdominal wall or cryopreserve
- transfer to NSICU without extubation.
- standard ICU ICP management
- attempt early extubation without gagging
- early enteral nutrition by POD1
- SQH after 24 hours unless with C/I
- early trach / PEG if needed
- if stable post-op CT, ASA after 24 h
- aggressive PT, speech, rehab
While technical details certainly vary between individual surgeons or centers, this brief outline describes a typical operation: the procedure is performed in a supine position with the head rotated to the contralateral side. A wide curved incision is performed either beginning behind or in front of the ear. The scalp flap and temporalis muscle are then deflected to expose the skull. Burr holes are created and subsequently connected to achieve an anterior to posterior diameter of the craniectomy area of at least 12 cm, with the recommended diameter in adult TBI
patients being 15 cm. The DC is finally extended to expose the floor of the middle cranial fossa. An adequately sized craniectomy is essential in achieving the desired decompressive effect. Moreover, a suboptimal DC will lead to exacerbated external brain her niation and shear forces at the bone edges, which can cause intraparenchymal hemorrhage and kinking of the cerebral
veins. After sufficient bony decompression has been achieved, the dura is incised to create a large dural opening. For coverage of the exposed brain, allogenic or autologous dural grafts can be used.
- Hygroma / subdural fluid collection most common (50-58%), most clinically insignificant
- delayed HCP in 7-12%
- infection 2-7%
- sinking flap syndrome (syndrome of trephined)
Operative technique of supratentorial DC. Artist’s rendition of a human head with a typical incision line for DC (gray line).
3D reconstruction of a human skull demonstrating burr holes (gray circles), craniectomy (gray area), and additional osteoclastic decompression of the middle cranial fossa floor (hatched area) as well as typical dural incision (red lines).
3D reconstruction of a human skull with a typical hemicraniectomy skull defect:
Intraoperative photography of a human brain after DC:
stepwise reduction in ICP after decompressive hemicraniectomy:
Suboccipital or Infratentorial Decompressive Craniectomy
In comparison with supratentorial DC, the technical details of suboccipital or infratentorial DC are less clearly established. Important aspects such as overall craniectomy size, laterality of the decompression, and necessity of resection of the posterior arch of the atlas all vary in the published literature. However, the basic surgical aim is decompression above the swollen cerebellum. In general, this procedure is performed with the patient in a prone or semi-prone/lateral position. A linear midline incision is made from the inion to the upper cervical spine, and the muscular layers are subsequently separated in the midline avascular plane, exposing the suboccipital skull, atlanto-occipital membrane, and posterior arch of the atlas. A wide craniectomy is performed extending into the foramen magnum. As the next step, to avoid tonsillar herniation, we routinely remove the posterior arch of the atlas. The dura is then usually opened in a Y-shaped fashion, and an expansion duroplasty is performed.
2018 AHA ASA Guidelines:
The guideline recommends early transfer of patients at risk of malignant cerebral edema to a center with neurosurgical expertise. Patient-centered preferences in shared decision-making regarding the interventions and limitations of care should be ascertained at an early stage. With regard to neurosurgical management, the guideline states that in patients ≤ 60 years of age, who deteriorate neurologically (defined as a decrease in the level of consciousness attributed to brain swelling despite medical therapy) within 48 h after MCA infarction, DC with expansion duroplasty is reasonable. In patients > 60 years of age, the same approach may be considered. For patients with cerebellar malignant stroke, the guideline recommends sub-occipital DC with expansion duroplasty upon neurological deterioration despite medical therapy, with concurrent EVD insertion to treat obstructive hydrocephalus.
Gupta, Aman et al. “Hemicraniectomy For Ischemic And Hemorrhagic Stroke”. Neurosurgery Clinics of North America 28.3 (2017): 349-360.
Beez, T., Munoz-Bendix, C., Steiger, H. and Beseoglu, K. (2019). Decompressive craniectomy for acute ischemic stroke. Critical Care, 23(1).