Polyetheretherketone Implant Cranioplasty for Large Cranial Defects: A Seven-Year Follow-Up

Background: Goals of a cranioplasty include protection of the brain, restoration of normal appearance, and neurological function improvement. Although choice of materials for cranial remodeling has changed through the years, computer-designed polyetheretherketone (PEEK) implant has gained traction as a preferred material used for cranioplasty. However, long-term outcomes and complications of PEEK implants remain limited. The goal of this study was to report long-term clinical outcomes after PEEK implant cranioplasty. Methods: A retrospective chart review was performed on patients undergoing PEEK cranioplasty between January 2007 and February 2023. Preoperative, intraoperative, and postoperative data were collected and analyzed. Results: Twenty-two patients were included in this study. Mean postoperative follow-up time was 83.45 months (range: 35.47-173.87). Before PEEK implant cranioplasty, patients with multiple cranial procedures had undergone a mean of 2.95 procedures. PEEK implant cranioplasty indications were prior implant infection (14) and secondary reconstruction of cranial defect (8). The mean implant size was 180.43 cm²(range: 68.00-333.06). Four patients received a 2-piece implant. Postoperative complications included: perioperative subgaleal self-resolving fluid collection in 1 patient, hematoma in another, and 3 infections resulting in explantations with successful reinsertion in 2 patients. Four of 5 patients with preoperative history of seizures reported improved seizures and all 4 patients with preoperative syndrome of the trephined reported improved symptoms and neurological function. Conclusion: At a mean follow-up of 7 years, most PEEK implants continued to provide protection to the brain and consistent symptom relief in patients suffering from prior postcraniectomy/craniotomy sequelae of seizures and syndrome of the trephined.