Effect of Early Surgery, Material, and Method of Flap Preservation on Cranioplasty Infections: A Systematic Review

Abstract
Infection is a significant cause of morbidity with cranioplasty procedures. However, few studies have investigated the effect of specific surgical practices on cranioplasty infection. To analyze the literature on the effect of early surgery (within 3 months of craniectomy), implant material, and method of flap preservation on cranioplasty infections, and to perform a subanalysis of the effect of early surgery on overall complications associated with cranioplasty. A systematic search of the PubMed, Cochrane, SCOPUS, and CINAHL databases was conducted. Comparative studies that reported on timing of surgery, implant material (autograft vs allograft), or method of flap preservation (subcutaneous vs extracorporeal), and infection or complication rates were selected for detailed analysis. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each analysis. Eighteen articles (2254 data points) met criteria for inclusion. There was no difference in infection rates (OR, 1.35; 95% CI, 0.53-3.41; P = .53) or overall complication rates (OR, 0.57; 95% CI, 0.29-1.11; P = .10) between early or later surgery. Fourteen studies (n = 1582) compared infection rates between autograft and allograft materials; there was no difference in infection rates between the two (OR, 0.81; 95% CI, 0.40-1.66; P = .57). There was no significant difference in infection rates between subcutaneous or extracorporeal preservation (OR, 0.35; 95% CI, 0.09-1.35; P = .13). Analysis of the best current evidence suggests that early surgery, implant material, and method of flap preservation have no effect on the rate of cranioplasty infections.