Bone Graft Expansion in Cranioplasty Using a Split-Bone Technique

Decompressive hemicraniectomy (DHC) is performed in emergent cases of uncontrollable intracranial hypertension in which noninvasive procedures or medications are not able to safely maintain pressure within the cranium, increasing the risk of morbidity and mortality. The native bone flap is then replaced, a procedure referred to as cranioplasty, nearly three to six months after injury to allow time for brain relaxation. However, in cases with persistent cerebral edema at the time of cranioplasty, techniques are often applied intraoperatively, including mannitol, external ventricular drain, or lumbar drain placement. To avoid the risks of delaying the procedure or drain placement, we demonstrate a novel technique of splitting the bone flap to adequately increase the size and flexibility. Three patients with a mean age of 44 underwent this novel technique during cranioplasty due to persistent brain edema following a DHC. The new operative technique was successfully performed to compensate for the lingering edema, and all three patients were monitored postoperatively, showing no complications. In this study we demonstrate a new technique to alter bone flap size and flexibility during cranioplasty cases with persistent brain edema, avoiding the need for invasive drain placement. All patients experienced no complications or new cranial/skull defects postoperatively.