Abstract: An object of the present invention is to provide a medical image data alignment apparatus, method and program capable of aligning different kinds of image data on a tissue to be objected at high precision and in a short time. According to the present invention, a patient SPECT and a patient CT are aligned via atlas data. The atlas data is a standard of SPECT image data, and is created based on SPECT image data of a plurality of patients. The patient SPECT and the atlas data are aligned based on the correlation of image signal values thereof, and a first transformation matrix T1 is determined. The atlas data and the patient CT are aligned based on the coordinate information added to these data in advance, and a second transformation matrix T2 is determined. The patient SPECT and the patient CT are aligned using the first transformation matrix T1 and the second transformation matrix T2.

Abstract: A tissue extraction system for extracting tissue from a subject by using an image, wherein the tissue extraction system comprises: an imaging unit for arranging coordinate axes to capture a plurality of sequences; a conversion unit for converting the plurality of sequences captured by the imaging unit into histogram space in which the sequences are described in terms of the coordinate axes; and an extraction unit for extracting the tissue of the subject from the distribution of the histogram converted by the conversion unit.

Abstract: An image-constituting element group corresponding to bone areas is selected from among a plurality of image-constituting elements that make up a three-dimensional image model, and CT values originally associated only with the selected image-constituting element group are replaced by values resulting from multiplying the original values by ¼. As a result, a distribution curve 34A denoting a frequency distribution of bone is shifted to a region of CT values that are lower than those of a distribution curve 33 denoting a frequency distribution of blood vessels. An observation image is then constructed by maximum intensity projection on the basis of three-dimensional image data after such signal value replacement.

Abstract: An object of the present invention is to provide a medical image data alignment apparatus, method and program capable of aligning different kinds of image data on a tissue to be objected at high precision and in a short time. According to the present invention, a patient SPECT and a patient CT are aligned via atlas data. The atlas data is a standard of SPECT image data, and is created based on SPECT image data of a plurality of patients. The patient SPECT and the atlas data are aligned based on the correlation of image signal values thereof, and a first transformation matrix T1 is determined. The atlas data and the patient CT are aligned based on the coordinate information added to these data in advance, and a second transformation matrix T2 is determined. The patient SPECT and the patient CT are aligned using the first transformation matrix T1 and the second transformation matrix T2.

Abstract: An image-constituting element group corresponding to bone areas is selected from among a plurality of image-constituting elements that make up a three-dimensional image model, and CT values originally associated only with the selected image-constituting element group are replaced by values resulting from multiplying the original values by 1/4. As a result, a distribution curve 34A denoting a frequency distribution of bone is shifted to a region of CT values that are lower than those of a distribution curve 33 denoting a frequency distribution of blood vessels. An observation image is then constructed by maximum intensity projection on the basis of three-dimensional image data after such signal value replacement.

Abstract: In the present invention, the difference between regions in which the signal value ranges are close to each other or the presence of overlapping regions of signal values can be clearly displayed on a predetermined image region of an observation image, and the displayed regions and display state thereof can be easily adjusted based on the signal value ranges. The present invention is configured such that a plurality of separate and mutually independent display property curves can be set on the same coordinate system, and a color and a degree of opaqueness, which are established by any number of display property curves from among the plurality of display property curves that are set, can be at once reflected in the image within the region to be observed.

Abstract: From CT images having captured an abdomen, a two-dimensional characteristic space is assumed, in which X and Y axes indicate CT values of image data taken in first and second time phases different from each other. In this space, a two-dimensional histogram concerning respective pixels located at the same position in the two time phases is taken as a sample distribution of pixels. A two-variable distribution function is applied to this sample distribution, so as to estimate a matrix distribution of pixels corresponding to the whole liver region. According to this matrix distribution, a range of CT value of pixels corresponding to the liver region is estimated.