Mammography device, radiographic imaging method, and program

A mammography device, comprising:

• an x-ray radiation source that emits x-ray radiation to a breast at a plurality of different emission angles;
• a condition setting unit that sets irradiation conditions corresponding to an emission angle of x-ray radiation emitted from the x-ray radiation source;
• an image generation unit that generates a plurality of projection images corresponding to the plurality of emission angles by detecting x-ray radiation, which is emitted from the x-ray radiation source based on the irradiation conditions set by the condition setting unit and is transmitted through the breast;
• a correction unit that corrects each projection image such that a difference between at least either contrasts or density values in the plurality of projection images is reduced;
• and
• a reconstruction unit that reconstructs a tomographic image based on the plurality of projection images corrected by the correction unit,
• wherein the condition setting unit increases a set value of a tube voltage in the x-ray radiation source as a transmission distance of x-ray radiation transmitted through the breast increases according to the emission angle of x-ray radiation, and
• wherein the correction unit converts a density value of a projection image corresponding to each of other emission angles such that differences between density values of at least three pixel groups in a projection image corresponding to a predetermined emission angle and density values of pixel groups corresponding to the at least three pixel groups in the projection image corresponding to each of the other emission angles are reduced.

A mammography device, comprising:

• an x-ray radiation source that emits x-ray radiation to a breast at a plurality of different emission angles;
• a condition setting unit that sets irradiation conditions corresponding to an emission angle of x-ray radiation emitted from the x-rayg23 radiation source;
• an image generation unit that generates a plurality of projection images corresponding to the plurality of emission angles by detecting x-ray radiation, which is emitted from the x-ray radiation source based on the irradiation conditions set by the condition setting unit and is transmitted through the breast;
• a correction unit that corrects each projection image such that a difference between at least either contrasts or density values in the plurality of projection images is reduced;
• and
• a reconstruction unit that reconstructs a tomographic image based on the plurality of projection images corrected by the correction unit,
• wherein the condition setting unit increases a set value of a tube voltage in the x-ray radiation source as a transmission distance of x-ray radiation transmitted through the breast increases according to the emission angle of x-ray radiation, and
• wherein the correction unit converts a density value of each of the plurality of projection images such that a density value of a first pixel in each of the plurality of projection images matches a first standard density value set for the first pixel and a density value of a second pixel in each of the plurality of projection images matches a second standard density value set for the second pixel.

A mammography device, comprising:

• an x-ray radiation source that emits x-ray radiation to a breast at a plurality of different emission angles;
• a condition setting unit that sets irradiation conditions corresponding to an emission angle of x-ray radiation emitted from the x-ray radiation source;
• an image generation unit that generates a plurality of projection images corresponding to the plurality of emission angles by detecting x-ray radiation, which is emitted from the x-ray radiation source based on the irradiation conditions set by the condition setting unit and is transmitted through the breast;
• a correction unit that corrects each projection image such that a difference between at least either contrasts or density values in the plurality of projection images is reduced;
• and
• a reconstruction unit that reconstructs a tomographic image based on the plurality of projection images corrected by the correction unit,
• wherein the correction unit converts image data of each of the plurality of projection images into data in a frequency domain by performing a Fourier transform, and performs filtering processing for multiplying the data in the frequency domain by a filter function of increasing the amount of emphasis in each frequency band as a transmission distance of x-ray radiation transmitted through the breast increases according to the emission angle of x-ray radiation.

A radiographic imaging method, comprising:

• setting irradiation conditions corresponding to an emission angle of x-ray radiation emitted from an x-ray radiation source;
• emitting x-ray radiation from the x-ray radiation source to a breast at a plurality of different emission angles based on the set irradiation conditions;
• generating a plurality of projection images corresponding to the plurality of emission angles by detecting x-ray radiation, which is emitted from the x-ray radiation source and is transmitted through the breast;
• correcting each projection image such that a difference between at least either contrasts or density values in the plurality of projection images is reduced;
• and
• reconstructing a tomographic image based on the plurality of the corrected projection images,
• wherein setting irradiation conditions includes increasing a set value of a tube voltage in the x-ray radiation source as a transmission distance of x-ray radiation transmitted through the breast increases according to the emission angle of x-ray radiation, and
• wherein correcting each projection image includes converting a density value of a projection image corresponding to each of other emission angles such that differences between density values of at least three pixel groups in a projection image corresponding to a predetermined emission angle and density values of pixel groups corresponding to the at least three pixel groups in the projection image corresponding to each of the other emission angles are reduced.