Comparison of Titanium and Carbon Fiber-Reinforced Polyetheretherketone Spinal Implants in Postoperative Spine Stereotactic Body Radiation Therapy: A Comprehensive Review of Current Evidence and Future Perspectives.

Postoperative stereotactic body radiation therapy (SBRT) for spinal metastases presents technical challenges, particularly in the presence of internal fixation devices. Titanium implants-the standard implant material-cause substantial imaging artifacts in computed tomography (CT) and magnetic resonance (MR) scans, which can lead to target and organ-at-risk contouring problems and compromise the accuracy of dose calculations. Meanwhile, carbon fiber-reinforced polyetheretherketone (Carbon/PEEK) implants have emerged as radiolucent alternatives with favorable imaging properties. This review summarizes the current evidence comparing titanium and Carbon/PEEK implants in the context of postoperative spine SBRT, focusing on differences in artifact size in CT and MR imaging, contouring accuracy, dose perturbation, dose calculation accuracy, image guided radiation therapy, radiation therapy robustness to setup error, and clinical outcomes in photon and proton therapies.