A method for imaging a volume within a patient volume is provided. The method includes generating a first signal and a second signal, directing the first signal and the second signal to a spot in the patient volume； receiving a first response signal and a second response signal from the spot in the patient volume； providing a first image from of the patient volume using the first response signal； providing a second image from the patient volume using the second response signal； and combining the first image and the second image to form a composite image. The method includes receiving multiple images at multiple frequency ranges； selecting a region of interest including the plurality of images； selecting multiple border lines separating the region of interest into multiple sub-regions； selecting data from an image in a sub-region； and forming an image in the region of interest.
