System and method for segmenting medical image

A method for segmenting a medical image, including:

• acquiring a first type of medical image via reconstructing a first type of data, wherein the first type of medical image comprises a plurality of voxels;
• acquiring a second type of data for reconstructing a second type of medical image;
• executing preliminary segmentation to the first type of medical image, and obtaining at least an unambiguous region and at least an ambiguous region;
• generating an attenuation map by assigning different attenuation coefficients corresponding to voxels belonging to different regions of the first type of image being executed preliminary segmentation;
• iteratively estimating the second type of data and the attenuation map to generate the second type of medical image and an estimated attenuation map;
• reassigning attenuation coefficients to the voxels of the first type of medical image based on the estimated attenuation map;
• and
• segmenting the first type of medical image into a plurality of sub-regions distinguished from each other.

A system for segmenting a medical image, the system comprising:

• an image processor comprising:
• a first reconstruction module configured to acquire an MR image via reconstructing the MR data;
• a segmentation module configured to segment the MR image into at least an air/bone ambiguous region and a soft-tissue region, wherein the air/bone ambiguous region comprises air voxels and bone voxels undistinguished from each other, and the soft-tissue region comprises only voxels of soft-tissue;
• a second reconstruction module configured to
• assign initial attenuation coefficient to each voxel of the MR image being segmented, and generate an attenuation map, wherein voxels of the air/bone ambiguous region are assigned attenuation coefficient of water;
• iteratively update the PET data and the attenuation map to generate a PET image and an estimated attenuation map;
• and,
• reassign attenuation coefficient to each voxel of the MR image being segmented based on the estimated attenuation map.