INTERVENTIONAL OR NON-INTERVENTIONAL INSTRUMENT FOR USE IN AN MRI APPARATUS

摘要

An interventional or a non-interventional instrument like a catheter, a surgical device, a biopsy needle, a pointer, a stent or another invasive or non-invasive device, like a position marker, or a surface or local coil like a head coil is disclosed, wherein these instruments are provided with an MR-safe RF transmission line or cable (2, 3) for connecting the instrument with related RF transmit/MR receive units or other signal processing units for operating the instrument during an MR imaging or MR examination of an examination object. Basically, MR safety is obtained or increased by means of a plurality of fuses (6) which are serially connected into the transmission line or cable (2, 3).

主权项

1. Interventional or non-interventional instrument for use during an MR imaging or MR examination of an examination object, the instrument comprising an RF transmission line or cable for connecting the instrument with a signal processing unit, characterized in that the RF transmission line or cable comprises a plurality of fuses which are serially connected into the RF transmission line or cable, wherein adjacent fuses have a distance (L) from one another which is equal to or shorter than a quarter of an effective wavelength of an RF common mode current which is induced in the RF transmission line or cable when exposed to an RF excitation field of an MR imaging apparatus, and wherein each fuse is selected such that it turns into an at least substantially non-conducting state when the current flowing through the fuse or the temperature of the fuse due to the current flowing through the fuse reaches or exceeds a preset threshold value.