Combining position-based dynamics and gradient vector flow for 4D mitral valve segmentation in TEE sequences. - Lennart Tautz; Lars Walczak; Joachim Georgii; Amer Jazaerli; Katharina Vellguth; Isaac Wamala; Simon H. Sündermann; Volkmar Falk; Anja Hennemuth (Int. J. Comput. Assist. Radiol. Surg., 2020)