Introduction: The predictors of graft infection after cranioplasty (GIC) following decompressive craniectomy are not well established. Knowledge of the risk factors for GIC will allow development of preventive measures designed to reduce infection rates. Therefore, the objective of this study was to identify risk factors for the development of GIC.

Methods: A total of 85 patients underwent reconstructive cranioplasty after decompressive craniectomy between January 2009 and July 2011, had a follow-up period of >1 year and charts were reviewed retrospectively. Indications for cranioplasty included trauma(49.5%) and vascular disease. Although autograft was used whenever possible, both autograft (69.4%) and artificial bone (30.6%) were used for cranioplasty. GIC was defined infection requiring removal of the bone graft.

Results: GIC occurred in 6 patients (7.05%). GIC was not related to the indications for craniectomy, the interval between craniectomy and cranioplasty, graft material, or the size of the bone defect (p = 0.433, p = 0.206, p = 0.665, and p = 0.999, respectively). The GIC rate was significantly related to previous temporalis muscle resection, pre-operative subgaleal fluid collection, cranioplasty operative times >120 min, and post-operative wound disruptions (p = 0.001, p < 0.001, p = 0.035, and p = 0.016, respectively). Multiple logistic regression showed that the presence of a subgaleal fluid collection before cranioplasty significantly increased the risk of GIC (OR: 38.53; 95% CI: 2.77–535.6; p = 0.006).

Conclusions: The results of this study suggest that long operative times, craniectomy with temporalis muscle resection, the presence of pre-operative subgaleal fluid collection, and post-operative wound disruption may be risk factors for acute infection after cranioplasty. Surgical techniques should be developed to reduce operative time and to avoid temporalis muscle resection when possible. In addition, meticulous dural closure aimed at reducing the formation of subgaleal fluid collection is important for the prevention of bone graft infections after cranioplasty.

Patient Care: In this study, we aimed to identify the risk factors for the development of graft infection after cranioplasty. Our findings suggest that long operative times (>120 min), craniectomy with temporalis muscle resection, the presence of preoperative subgaleal fluid collection(s), and postoperative wound disruption may be risk factors for graft infection after cranioplasty. We suggest that surgical techniques should be developed to reduce operative time and to avoid temporalis muscle resection when possible.

Learning Objectives: By the conclusion of this session, participants should be able to: 1)long operative times (>120 min), craniectomy with temporalis muscle resection, the presence of preoperative subgaleal fluid collection(s), and postoperative wound disruption may be risk factors for graft infection after cranioplasty

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