Primary Design Concept for Non-metallic Needle for MRI Guided Spinal Applications

This work describes an initial design concept for a spinal needle using new materials to optimize their visualization in magnetic resonance imaging. Common MRI needles made of Nickel-Titanium alloys still show poor visibility in imaging because they generate susceptibility artifacts due to material’s interactions with the magnetic environment. The use of non-metallic materials can reduce these artifacts. However, so far no non-metallic needle design has made it to clinical routine due to sharpness and cost issues. We propose a design of a coaxial needle with a fiber enforced inner core and an outer hollow sheet. The concept has been evaluated in the MRI environment. Additionally, mechanical tests were performed to examine and quantify the variation between a conventional spinal needle and our proposed design.