Passive artifact behavior prediction of interventional tools in high-field MRI using a 0.55T portable benchtop MR scanner.

Using magnetic resonance imaging (MRI) for guiding minimally invasive interventions requires surgical devices which on one hand are visible in the MR image but on the other hand do not generate large artifacts, which distort the overall imaging process. Passive markers are one way to visualize devices such as catheters or biopsy needles in MRI. The evaluation of newly developed passive markers usually requires access to high-field MRI scanners (1.5 T and 3 T). This makes the practical evaluation time-consuming and expensive. Hence, we propose to use a high-resolution, low field (0.55 T) benchtop MRI system to quantify the size of an artifact and to make a prediction for its corresponding size in a clinical high-field system. For the evaluation of the proposed method, catheters coated with different passive marker materials in varying concentrations were imaged in the 0. 55 T benchtop MRI scanner as well as in clinical 3 T MRI system using FLASH sequences. The experimental results revealed that an artifact prediction based on measurements in the 0. 55 T is possible for the tested marker materials. Hence, the proposed approach has a high potential for testing newly developed medical devices at a low cost, in less time and during the development process for fast feedback.