Bleeding:
(1) new ipsilateral hematoma
(2) new contralateral or remote hematoma
(3) contusion expansion
(4) hemorrhagic transformation of an ischemic infarction
Wound or cranial defect related:
(1) infection (surgical site, meningitis, ventriculitis, abscess)
(2) inflammation
(3) poor wound healing
(4) ischemia of the scalp flap
(5) syndrome of the trephined
(6) paradoxical herniation due to atmospheric pressure
(7) falls on unprotected cranium
CSF related:
(1) hydrocephalus
(2) subdural hygroma
(3) CSF leak or fistula
Cranioplasty related:
(1) any of the problems listed above
(2) problems of cosmesis
(3) aseptic bone resorption
