Estimating cardiac fiber orientations in pig hearts using registered ultrasound and MR image volumes

• Authors: James D. Dormer, Emory University; Yuguang Meng, Emory University; Xiaodong Zhang, Emory University; Rong Jiang, Emory University; Mary Wagner, Emory University; Baowei Fei, Emory University
• Journal Title: Proceedings of SPIE
• Volume: Volume 10139
• Publisher: Society of Photo-optical Instrumentation Engineers (SPIE) | 2017-01-01
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1117/12.2255515
• Subjects: Health Sciences, Radiology
• Keywords: Science & Technology; Physical Sciences; Life Sciences & Biomedicine; Optics; Radiology, Nuclear Medicine & Medical Imaging; Magnetic resonance diffusion tensor imaging (MR-DTI); ultrasound imaging; cardiac fiber orientation; image registration; deformable registration; heart disease; cardiac fiber imaging

Abstract

Heart fiber mechanics can be important predictors in current and future cardiac function. Accurate knowledge of these mechanics could enable cardiologists to provide a diagnosis before conditions progress. Magnetic resonance diffusion tensor imaging (MR-DTI) has been used to determine cardiac fiber orientations. Ultrasound is capable of providing anatomical information in real time, enabling a physician to quickly adjust parameters to optimize image scans. If known fiber orientations from a template heart measured using DTI can be accurately deformed onto a cardiac ultrasound volume, fiber orientations could be estimated for the patient without the need for a costly MR scan while still providing cardiologists valuable information about the heart mechanics. In this study, we apply the method to pig hearts, which are a close representation of human heart anatomy. Experiments from pig hearts show that the registration method achieved an average Dice similarity coefficient (DSC) of 0.819 ± 0.050 between the ultrasound and deformed MR volumes and that the proposed ultrasound-based method is able to estimate the cardiac fiber orientation in pig hearts.