How large a decompressive hemicraniectomy should be and where is the most important part of the craniectomy?

A decompressive hemicraniectomy usually involves removal of large portion of the skull (including frontal, temporal and parietal regions of the skull) and is performed to relieve elevated intracranial pressure as last treatment option. The surgical procedure is done in cases of malignant stroke involving large vascular territories of the brain (e.g. middle cerebral artery), traumatic brain injury, or other conditions leading to brain edema. The size of the craniotomy is usually large, as is generally accepted that a larger craniectomy is more effective in reducing intracranial pressure. Usually, the typical size of the bone flap is 12-15 cm. However one of the most important part is removal of the temporal bone to the base of the skull as this directly decompresses the temporal lobe and decreases the risk of trans-tentorial herniation.