Optimizing the Visibility of a Carbon Fiber Cannula in Spin Echo Sequences Using Currents Induced by Gradient Switching in an Attached Copper Loop: A Feasibility Study

Hanne Wojtczyk¹, Hansjoerg Graf¹, Petros Martirosian¹, Anika Klabes¹, Stefan Kegel¹, Verena Ballweg¹, Christoph Thomas², Fritz Schick¹

Some instruments for interventional MRI procedures, e.g. a carbon fiber cannula, do not produce pronounced signal voids or artifacts. The feasibility of optimizing their visibility by surrounding the object with a loop of thin copper wire was evaluated theoretically and practically: currents induced in the copper loop by gradient switching shall be utilized to create individually controlled gradient echo like artifacts in spin echo sequences. A carbon fiber tube and straws of different lengths were surrounded by loops of copper wire of different diameter and imaged at 1.5 T. The approach works in principle but may be not very practical, however possibly expandable.