Minimal artifact actively shimmed metallic needles in MRI.

ABSTRACT:

Purpose

Signal voids caused by metallic needles pose visualization and monitoring challenges in many MRI applications. In this work, we explore a solution to this problem in the form of an active shim insert that fits inside a needle and corrects the field disturbance (ΔB₀ ) caused by the needle outside of it.

Methods

The ΔB₀ induced by a 4 mm outside-diameter titanium needle at 3T is modeled and a two-coil orthogonal shim set is designed and fabricated to shim the ΔB₀ . Signal recovery around the needle is assessed in multiple orientations in a water phantom with four different pulse sequences. Phase stability around the needle is assessed in an ex-vivo porcine tissue dynamic gradient echo experiment with and without shimming. Additionally,

SUBMITTER: Sengupta S 

PROVIDER: S-EPMC8868020 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature