Multiple Cerebral Hemorrhages Caused by Paradoxical Reperfusion Injury After Cranioplasty.

Cranioplasty-related reperfusion injury has rarely been reported. Although there are several hypotheses, particularly regarding the mechanisms of the event, clear evidence is lacking. Here, we report the case of an 84-year-old man with traumatic intracranial hemorrhage and subdural hematoma who underwent decompressive craniectomy and hematoma evacuation in the right hemisphere. After 45 days, cranioplasty was performed using titanium. A preoperative perfusion study with 99m-Tc-HMPAO brain single-photon emission tomography revealed diffuse hypoperfusion in the left cerebral hemisphere with decreased vascular reserve. After cranioplasty, multiple cerebral hemorrhages were observed on immediate postoperative computed tomography. Cerebral hemorrhage eventually improved without surgery. Here, we report a case with findings revealed through perfusion studies before and after surgery.