Magnetic resonance elastography for ultrasound image simulation

#The present embodiments relate to ultrasound image simulation. Ultrasound images are easily acquired during an interventional or radiotherapy procedure. However, ultrasound images may lack the resolution or detail of computed tomography (CT) images. A CT volume may be acquired prior to the procedure and may be valuable for guidance during the procedure.

#By registering the ultrasound images with the pre-operative CT volume, real-time and detailed information are both provided during the procedure. To register these different modalities, the CT volume may be used to simulate an ultrasound image. The pseudo-ultrasound simulations may better register with the actual ultrasound images. To simulate ultrasound from the CT volume, the acoustic properties (e.g., density of tissue) from the CT volume are used. The Houndsfield Unit (HU) from CT may be used as an estimate of density.

#Magnetic resonance (MR) imaging may have different or greater variety of functional and/or anatomical information than CT imaging. However, MR imaging does not produce information as closely resembling density as provided by CT imaging. Physical sensors or feature recognition may be used for registration of ultrasound with MR, but sensors and feature recognition may make examination more expensive or difficult or be inaccurate.

#The components and the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like reference numerals designate corresponding parts throughout the different views.

#FIG. 1 is a block diagram of one embodiment of a system for ultrasound data simulation using magnetic resonance elastography; and

#FIG. 2 is a flow chart diagram of one embodiment of a method for ultrasound data simulation using magnetic resonance elastography.

#MR elastography is used to obtain images describing the elastic properties or density of the volume. For registration and/or fusion, ultrasound images are simulated from the elastic properties or density information. Since elastography directly models the material properties of sound waves within the volume, ultrasound images may be accurately simulated through the volume.

#A real-time system capable of MR to ultrasound image registration is provided. Such a system may be particularly useful as compared to CT due to less radiation exposure. For example, CT imaging may not be used for breasts due to radiation exposure. Simulation of ultrasound from MR elastography may allow for fusion of real-time ultrasound information with more detailed pre-operative MR anatomy information in procedures for the breast, liver, kidney, or other organs. The ultrasound simulation with MR elastography may be used for registration for diagnosis or treatment of any organ.

#FIG. 1 shows a system 10 for ultrasound data simulation using magnetic resonance elastography. The system 10 includes a memory 12, an MR system 14, an ultrasound system 16, a transducer 18, a processor 26, and a display 28. Additional, different, or fewer components may be provided. For example, a network or network connection is provided, such as for networking with a medical imaging network or data archival system. As another example, separate transducers 18 are used for acquiring MR elastography data and ultrasound data. In another example, a user interface is provided. In yet another example, the ultrasound system 16 and transducer 18 are not provided where the system 10 just generates an ultrasound simulation. The MR system 14 may not be provided in some embodiments, such as where the MR data is acquired by transfer or from storage.