Carbon Fiber/Polyether Ether Ketone (CF/PEEK) Implants Allow for More Effective Radiation in Long Bones

Abstract

Background: Metallic implants show dose-modulating effects in radiotherapy and complicate its computed tomography (CT)-based planning. Dose deviations might not only affect the surrounding tissues due to backscattering and inadvertent dose increase but might also compromise the therapeutic effect to the target lesion due to beam attenuation. Later on, follow-up imaging is often obscured by metallic artefacts. Purposes: This study investigates the dosimetric impact of titanium and radiolucent carbon fiber/polyether ether ketone (CF/PEEK) implants during adjuvant radiation therapy in long bones. (1) Does the use of CF/PEEK implants allow for a more homogenous application of radiation? (2) Is the dose delivery to the target volume more efficient when using CF/PEEK implants? (3) Do CF/PEEK implants facilitate CT-based radiation therapy planning? Materials and methods: After CT-based planning, bone models of six ovine femora were irradiated within a water phantom in two immersion depths to simulate different soft-tissue envelopes. Plates and intramedullary nails of both titanium and CF/PEEK were investigated. Radiation dosage and distribution patterns were mapped using dosimetry films. Results: First, the planned implant-related beam attenuation was lower for the CF/PEEK plate (1% vs. 5%) and the CF/PEEK nail (2% vs. 9%) than for corresponding titanium implants. Secondly, the effective decrease of radiation dosage behind the implants was noticeably smaller when using CF/PEEK implants. The radiation dose was not significantly affected by the amount of surrounding soft tissues. A significant imaging artefact reduction was seen in all CF/PEEK models. Conclusion: CF/PEEK implants lead to a more reliable and more effective delivery of radiation dose to an osseous target volume. With regard to radiation therapy, the use of CF/PEEK implants appears to be particularly beneficial for intramedullary nails.

Reduction of CT Artifacts Using Polyetheretherketone (PEEK), Polyetherketoneketone (PEKK), Polyphenylsulfone (PPSU), and Polyethylene (PE) Reconstruction Plates in Oral Oncology

“…Metal artifact reduction algorithms (MAR) for image optimization are incapable of preventing this effect (10). Hence, CT image quality needed for radiotherapy planning systems (TPS), dosimetric calculations around medical implants (11) or postoperative tumor follow-up deteriorates (12,13). Therefore, in the wake of scientific development of new and innovative chemical compositions of osteosynthesis materials radiolucency increasingly becomes important (14).…”

Experimental testing of fracture fixation plates: A review

“…Another shortcoming is the lack of radiolucency of the metallic plates which can be an obstacle when it comes to assessing the healing of the bone, and also poses an additional challenge with oncological patients or patients who require radiotherapy. 19 , 20 …”

Mechanical Properties and Gamma-Ray Shielding Performance of 3D-Printed Poly-Ether-Ether-Ketone/Tungsten Composites

“…With the rapid development of 3D printing of PEEK and PEEK composite materials, PEEK has widely been adopted for applications in biology, medicine, aerospace, and other fields [ 43 , 44 , 45 , 46 , 47 ]. However, only a handful of studies dealing with the nuclear radiation shielding performances of 3D-printed PEEK and PEEK composite materials have so far been reported.…”