Myocardial motion tracking stands as an essential clinical tool in the
prevention and detection of cardiovascular diseases (CVDs), the foremost cause
of death globally. However, current techniques suffer from incomplete and
inaccurate motion estimation of the myocardium in both spatial and temporal
dimensions, hindering the early identification of myocardial dysfunction. To
address these challenges, this paper introduces the Neural Cardiac Motion Field
(NeuralCMF). NeuralCMF leverages implicit neural representation (INR) to model
the 3D structure and the comprehensive 6D forward/backward motion of the heart.
This method surpasses pixel-wise limitations by offering the capability to
continuously query the precise shape and motion of the myocardium at any
specific point throughout the cardiac cycle, enhancing the detailed analysis of
cardiac dynamics beyond traditional speckle tracking. Notably, NeuralCMF
operates without the need for paired datasets, and its optimization is
self-supervised through the physics knowledge priors in both space and time
dimensions, ensuring compatibility with both 2D and 3D echocardiogram video
inputs. Experimental validations across three representative datasets support
the robustness and innovative nature of the NeuralCMF, marking significant
advantages over existing state-of-the-art methods in cardiac imaging and motion
tracking.Comment: 18 pages, 11 figure