A simulation-based analysis of the potential of compressed sensing for accelerating passive MR catheter visualization in endovascular therapy.

Passive MRI is a promising approach to visualize catheters in guiding and monitoring endovascular intervention and may offer several clinical advantages over the current x-ray fluoroscopy "gold standard." Endovascular MRI has limitations, however, such as difficulty in visualizing catheters and insufficient temporal resolution. The multicycle projection dephaser method is a background signal suppression technique that improves the conspicuity of passive catheters by generating a sparse (i.e., catheter only) image. One approach to improve the temporal resolution is to undersample the k-space and then apply nonlinear methods, such as compressed sensing, to reconstruct the MR images. This feasibility study investigates the potential synergies between multicycle projection dephaser and compressed sensing reconstruction for real-time passive catheter tracking. The multicycle projection dephaser method efficiently suppressed the background signal, and compressed sensing allowed MR images to be reconstructed with superior catheter conspicuity and spatial resolution when compared to the more conventional zero-filling reconstruction approach. Moreover, compressed sensing allowed the shortening of total acquisition time (by up to 32 times) by vastly undersampling the k-space while simultaneously preserving spatial resolution and catheter conspicuity.