Carbon fiber magnetic resonance compatible instruments

Abstract

Instruments are constructed of a carbon fiber material optionally doped with a doping agent such as iron oxide, the instrument having a magnetic susceptibility being adjusted to a portion of a subject being imaged. Therefore there is little effect upon the lines of magnetic flux and the magnetic field homogeneity, reducing distortion in an MR image. These carbon fiber instruments exhibit virtually no magnetic torsional forces when inserted into a magnetic field. This is important, for example when the instrument is a scalpel. Doped carbon fiber has minimal affect on radiofrequency fields. The instruments do not affect the homogeneity of an applied homogeneous magnetic field or an applied radiofrequency field. Doped carbon fiber exhibits a rigidity large enough to allow construction of high strength instruments such as biopsy needles. It also has the ability to retain a sharp edge, allowing construction of scalpels and cutting instruments. Doped carbon fiber surgical instruments may be used inside a magnetic field during magnetic resonance imaging, thereby allowing interactive internal images to be produced and displayed to a surgeon during surgery. A method is also disclosed for imaging a control material and then the instrument to determine the type and amount of doping agent required.