Aligning apparatus, aligning method, and the program

Abstract

An aligning method and apparatus for aligning images having different imaged regions with improved alignment accuracy. Aligning the imaged region of each of a plurality of partial images with an overall reference image. Then, two images having an overlapping area are aligned with each other based on the amount of shift when one of the two images is aligned with the overall reference image, and the amount of shift when the other of the two images is aligned with the overall reference image.

1 . An aligning apparatus comprising:
 a first model image storing means for storing a first normal density distribution model image obtained by a first imaging apparatus, the first normal density distribution model image representing a plurality of anatomical structures in normal density values normally appearing on the images obtained by the first imaging apparatus;   a second model image storing means for storing a second normal density distribution model image obtained by a second imaging apparatus, the second normal density distribution model image representing a plurality of anatomical structures in normal density values normally appearing on the images obtained by the second imaging apparatus;   a first image storing means for storing a first image that includes an anatomical structure obtained by imaging a predetermined subject using the first imaging apparatus;   a second image storing means for storing a second image that includes an anatomical structure obtained by imaging the predetermined subject using the second imaging apparatus;   a first aligning means for aligning a corresponding anatomical structure between the first normal density distribution model image and the first image to obtain a first corresponding position;   a second aligning means for aligning a corresponding anatomical structure between the second normal density distribution model image and the second image to obtain a second corresponding position; and   a corresponding position obtaining means for obtaining a corresponding position of the anatomical structure between the first and second images from a corresponding position of a corresponding anatomical structure between the first normal density distribution model image and the second normal density distribution model image, the first corresponding position, and the second corresponding position.   
     
     
         2 . The aligning apparatus according to  claim 1 , wherein the first or second imaging apparatus is any of a CT scanner, a PET scanner, and a MRI machine. 
     
     
         3 . An aligning method for use with an aligning apparatus that includes:
 a first model image storing means for storing a first normal density distribution model image obtained by a first imaging apparatus, the first normal density distribution model image representing a plurality of anatomical structures in normal density values normally appearing on the images obtained by the first imaging apparatus;   a second model image storing means for storing a second normal density distribution model image obtained by a second imaging apparatus, the second normal density distribution model image representing a plurality of anatomical structures in normal density values normally appearing on the images obtained by the second imaging apparatus;   a first image storing means for storing a first image that includes an anatomical structure obtained by imaging a predetermined subject using the first imaging apparatus; and   a second image storing means for storing a second image that includes an anatomical structure obtained by imaging the predetermined subject using the second imaging apparatus, the method comprising:   a first aligning step for aligning a corresponding anatomical structure between the first normal density distribution model image and the first image to obtain a first corresponding position;   a second aligning step for aligning a corresponding anatomical structure between the second normal density distribution model image and the second image to obtain a second corresponding position; and   a corresponding position obtaining step for obtaining a corresponding position of the anatomical structure between the first and second images from a corresponding position of a corresponding anatomical structure between the first normal density distribution model image and the second normal density distribution model image, the first corresponding position, and the second corresponding position.   
     
     
         4 . A program for causing a computer to function as:
 a first model image readout means for reading out a first normal density distribution model image obtained by a first imaging apparatus, the first normal density distribution model image representing a plurality of anatomical structures in normal density values normally appearing on the images obtained by the first imaging apparatus;   a second model image readout means for reading out a second normal density distribution model image obtained by a second imaging apparatus, the second normal density distribution model image representing a plurality of anatomical structures in normal density values normally appearing on the images obtained by the second imaging apparatus;   a first image readout means for reading out a first image that includes an anatomical structure obtained by imaging a predetermined subject using the first imaging apparatus, and stored in a first image storing means; and   a second image readout means for reading out a second image that includes an anatomical structure obtained by imaging the predetermined subject using the second imaging apparatus, and stored in a second image storing means;   a first aligning means for aligning a corresponding anatomical structure between the first normal density distribution model image and the first image to obtain a first corresponding position; and   a second aligning means for aligning a corresponding anatomical structure between the second normal density distribution model image and the second image to obtain a second corresponding position; and   a corresponding position obtaining means for obtaining a corresponding position of the anatomical structure between the first and second images from a corresponding position of a corresponding anatomical structure between the first normal density distribution model image and the second normal density distribution model image, the first corresponding position, and the second corresponding position.