Radiolucent Headholder Hybrid Pins Made of Carbon Fiber Reinforced Plastics and Aluminum for Intraoperative Image Evaluations.

Abstract

Computed tomography (CT) is the most widely applied intraoperative imaging technique in neurosurgery. However, tools for head fixation, especially headholder pins, are made of different materials, often with inadequate strength and radiolucency performance. None of the commercially available pins have both sufficient mechanical strength and radiolucency. Therefore, we aimed to develop and evaluate a novel approach to address this issue. We designed a hybrid-type headholder pin primarily composed of carbon fiber-reinforced plastic with an aluminum tip. We then compared its radiolucent performance and strength with existing pins using CT image evaluations and the American Society for Testing and Materials F3395 mechanical tests. The hybrid pin showed significantly fewer artifacts on qualitative image evaluation. The variations in CT brightness value for each pin were as follows (mean ± standard deviations): present study: 8.7 ± 3.2, carbon fiber-reinforced plastic with titanium alloy: 18.4 ± 4.2, sapphire: 22.4 ± 13.8. This hybrid pin showed significantly lower range of the density in Hounsfield unit for each column than other existing pins (P < 0.01). It also exhibited sufficient durability to withstand loads in both axial (360.0 N) and lateral directions (111.0 N), which is definitely sufficient to sustain the loads during clinical-use when compared with existing pins. The hybrid pin showed reduced artifacts and sufficient strength compared to existing pins. This device provides better quality intraoperative imaging for use as an external fixation device.