Generation of 4D access corridors from real-time multislice MRI for guiding transapical aortic valvuloplasties

Real-time image-guided cardiac procedures (manual or robot-assisted) are emerging due to potential improvement in patient management and reduction in the overall cost. These minimally invasive procedures require both real-time visualization and guidance for maneuvering an interventional tool safely inside the dynamic environment of a heart. In this work, we propose an approach to generate dynamic 4D access corridors from the apex to the aortic annulus for performing real-time MRI guided transapical valvuloplasties. Ultrafast MR images (collected every 49.3 ms) are processed on-the-fly using projections to extract a conservative dynamic trace in form of a three-dimensional access corridor. Our experimental results show that the reconstructed corridors can be refreshed with a delay of less than 0.5ms to reflect the changes inside the left ventricle caused by breathing motion and the heartbeat.