C ranioplasty is more than a cosmetic repair of cranial defects; it is part of the rehabilitation process following a patient's neurological injury. Recent studies have shown that cranioplasty may improve the patient's psychological status, social performance, and neurocognitive functioning. 1,14,19,21 The factors that contribute to periprocedural complications, including patients' demographic information, comorbidities, surgical procedure, and under lying disease, need to be thoroughly evaluated. Previous studies that were intended to answer these questions were limited by their design or by their sample size. Our aim was to evaluate risk factors that predispose patients to an increased risk of cranioplasty complications. Recent evidence in the literature emphasizes patient-specific factors over surgery-specific factors as major predictors of cranioplasty complications. 47,51 It is also becoming evident that surgical treatment for cranioplasty complications is associated with additional surgical procedures. 17,46 In this study, we evaluated the association between patient-specific factors and complications folabbreviatioNs AED = antiepileptic drug; DHC = decompressive hemicraniectomy; DM = diabetes mellitus; SAH = subarachnoid hemorrhage; TBI = traumatic brain injury. obJect The factors that contribute to periprocedural complications following cranioplasty, including patient-specific and surgery-specific factors, need to be thoroughly assessed. The aim of this study was to evaluate risk factors that predispose patients to an increased risk of cranioplasty complications and death. methods The authors conducted a retrospective review of all patients at their institution who underwent cranioplasty following craniectomy for stroke, subarachnoid hemorrhage, epidural hematoma, subdural hematoma, and trauma between January 2000 and December 2011. The following predictors were tested: age, sex, race, diabetic status, hypertensive status, tobacco use, reason for craniectomy, urgency status of the craniectomy, graft material, and location of cranioplasty. The cranioplasty complications included reoperation for hematoma, hydrocephalus postcranioplasty, postcranioplasty seizures, and cranioplasty graft infection. A multivariate logistic regression analysis was performed. Confidence intervals were calculated as the 95% CI. results Three hundred forty-eight patients were included in the study. The overall complication rate was 31.32% (109 of 348). The mortality rate was 3.16%. Predictors of overall complications in multivariate analysis were hypertension (OR 1.92, CI 1.22-3.02), increasing age (OR 1.02, CI 1.00-1.04), and hemorrhagic stroke (OR 3.84,). Predictors of mortality in multivariate analysis were diabetes mellitus (OR 7.56, CI 1.56-36.58), seizures (OR 7.25, CI 1.238-42.79), bifrontal cranioplasty (OR 5.40,, and repeated surgery for hematoma evacuation (OR 13.00, CI 1.51-112.02). Multivariate analysis was also applied to identify the variables that affect the development of seizures, the need for reoperation for hem...