Constructing an Average Geometry and Diffusion Tensor Magnetic Resonance Field from Freshly Explanted Porcine Hearts

摘要

The local arrangement of cardiac fibers provides insight into the electrical and mechanical functions of the heart.Fiber directions can be obtained using diffusion tensor (DT) MR imaging and further integrated into computa-tional heart models for accurate predictions of activation times and contraction. However, this information isnot available due to limitations of cardiac in-vivo DTI; thus, an average atlas could be used instead of individualfiber directions. In this work, we present a simple and computationally efficient pipeline for constructing a novelstatistical cardiac atlas from ex-vivo high resolution DT images of porcine hearts. Our framework involves nor-malizing the cardiac geometries, reorienting local directional information on diffusion, and computing the averagediffusion tensor field. The registration step eliminates the need for landmarks, while the tensor reorientationstrategy enables the transformation of the diffusion tensors and preserves the diffusion tensor orientations.