gms | German Medical Science

Objective: Autologous cranioplasty is a commonly performed operation after decompressive craniectomy (DC). However, protocols for bone flap preservation, timing and surgical technique vary between centers. In the absence of prospective randomized trials or large series no real evidence based recommendations can be given on crucial aspects. Complication rates are high and the rate of bone flap resorption varies between 10% to more than 80%. In this study we reviewed our institutional series.

Methods: This is a retrospective study of autologous cranioplasties performed in children after DC since 2010. According to our protocol, bone flaps are preserved in sterile packaging at -80°Celsius. We analyzed relevant variables and performed descriptive statistics.

Results: From a cohort of 15 children undergoing DC for trauma (N=12), hemorrhage (N=2) and ischemic stroke (N=1), 11 patients survived and received autologous cranioplasty (5 unilateral hemicraniectomies, 3 bilateral hemicraniectomies and 2 bifrontal craniectomies). Of note, a primary computer-aided design/computer-aided manufacturing (CAD/CAM) implant was necessary in only one case (1 unilateral hemicraniectomy with multiple fractures of autologous bone). Cranioplasties were performed at a mean latency of 1.5 months (range 1–2 months) after DC. Mean craniectomy area was 12166mm² (range 7520–15933mm²). Complications occurred in 6 cases (2 hygroma, 2 CSF leaks, 1 subdural hematoma, 1 infection), requiring revision surgery in 2 cases (repair of CSF fistula and removal of infected bone flap). Bone flap resorption was observed in 8 autologous implants after a mean period of 19 months (range 4-54 months) and implantation of a secondary CAD/CAM implant was performed in these cases. Mean follow-up was 25 months after DC (range 2–84 months).

Conclusion: Complication rate after cranioplasty was 43%, but the revision rate was only 14%. Bone flap resorption occurred in 62% and required implantation of a secondary CAD/CAM implant in all cases. Considering this significant rate of osteolysis and thus revision surgery, it is worthwhile to identify risk factors to identify high-risk patients who might benefit from a primary CAD/CAM implant. However, due to variations in local protocols and overall low incidence of pediatric DC, such data would be best collected in a multicenter prospective registry.