Abstract
Ultrasound is a widely used technology in breast cancer diagnosis. Ultrasound enables the real-time diagnosis, however, the information of general ultrasound scanner is limited (2D) and the tumor detectability is recognized as insufficient compared to that of MRI. Breast MRI imaging has high sensitivity and tumor detectability, but the number of MRI facilities is limited and it is both costly and time-consuming. Thus, we are developing the technology, which constructs a quasi supine MRI image from a prone MRI image using a particle method for fusion with an US image. The biggest challenge to apply US-MRI fusion in breast care area is the deformation of breast tissue; MRI scan is performed with patient in a prone position, whereas the ultrasound diagnosis is performed in a supine position. The present study employed the MPS (Moving Particle Semi-implicit) method to analyze the deformation of breast tissue due to gravity. We manually segmented a prone breast MRI image and generated particles on it for MPS method simulation. Homogeneous and small strain linear elasticity model were used in the simulation. Based on the calculated breast deformation result, we reconstruct a quasi-supine MRI image with backward warping method.
