Analysis of the timing and the usage of drains following cranioplasty on outcomes and the incidence of bone resorption.

Background: Pediatric cranioplasty is associated with a high rate of complications, including bone resorption (BR) in 20-50% of cases. We aimed to evaluate factors contributing to BR, including the effect of the timing of cranioplasty and the use of post-surgical drains. Methods: This is a dual institution retrospective review of all patients under 18 years old who underwent a cranioplasty following a decompressive craniectomy (DC) for the treatment of traumatic brain injury between 2011 and 2021. Early cranioplasty was defined as within 30 days after DC and late cranioplasty as >30 days. Patients were grouped by BR and separately by timing to cranioplasty. Groups were compared based on the Glasgow Outcome Scale (GOS) and postoperative drain usage. Results: A total of 30 patients were included in the study. The mean age was 7.39 (standard deviation = 6.52) and 60% were male. The median time to cranioplasty was 13 days (interquartile range = 10-17). BR was present in 16.7% of cases. A subgaleal drain was utilized in 93.3% and an external ventricular drain (EVD) in 63.3% of patients following cranioplasty. Drain usage was not associated with BR and timing to cranioplasty was not associated with discharge or 6-month GOS. Conclusion: This study demonstrates that early cranioplasty following DC may have similar outcomes to late cranioplasty. Post-surgical EVDs and subgaleal drains did not increase the incidence of BR, suggesting their importance in the postoperative management of these patients.