Skull Reconstruction Using a Custom-Made, Three-Dimensional–Printed, Hydroxyapatite-Titanium Cranioplasty Implant: Largest Single-Center U.S. Experience

Abstract

Although several material options, both natural and synthetic, are available for cranioplasty, the rate of implant-related complications has remained high. A relatively novel, synthetic hydroxyapatite-titanium implant, which combines biocompatibility with biomechanical resilience, has been reported to reduce tissue inflammation, infection, and explantation rates, while delivering superior cosmetic results. However, despite such promising preliminary reports, clinical data supporting its use have remained scarce. All the patients who had undergone cranioplasty between 2019 and 2022 using this implant were identified from a prospectively maintained database. Medical records were retrospectively reviewed and the following variables recorded: demographic data, clinical data, radiologic findings, operative details, complications (implant-related and unrelated), and outcomes. A total of 18 patients (12 men and 6 women), with a mean age of 39 years (range, 20-70 years), were identified. The indications for craniectomy were traumatic brain injury (n= 13; 72.2%), hemorrhagic stroke (n= 3; 16.7%), and ischemic stroke (n= 2; 11.1%). The median time to cranioplasty was 140 days (range, 51-1717 days). The median modified Rankin scale score before cranioplasty was 4 (range, 0-5). Cranioplasty was technically successful in all 18 patients. Minor postoperative complications, none related to the implant, were managed conservatively in 3 patients (16.6%), including a small intraparenchymal hematoma in 1, an extra-axial hematoma in 1, and a seizure in 1. Of these 3 patients, 1 (5.6%) died 1 week later of a suspected pulmonary embolism. No implant-related complications occurred after a median follow-up of 6 months (range, 1-38 months). All 17 survivors exhibited some degree of neurologic improvement. The cosmetic result was good or excellent for all patients. Our experience, the largest in the United States, confirms the previously reported benefits associated with the use of 3-dimensional-printed hydroxyapatite-titanium cranioplasty implants.