Tomographic image generating apparatus, tomographic image generating method, and tomographic image generating program

A tomographic image generating apparatus comprising at least one processor,

• wherein the processor is configured to:
• acquire a plurality of projection images corresponding to a plurality of radiation source positions, the plurality of projection images being generated by causing an imaging apparatus to perform tomosynthesis imaging in which a radiation source is moved relative to a detection surface of a radiation detector in order to emit radiation to a subject at the plurality of radiation source positions according to movement of the radiation source;
• reconstruct all or a part of the plurality of projection images to generate a tomographic image on each of a plurality of tomographic planes of the subject;
• detect a plurality of feature point from a plurality of the tomographic images;
• discriminate whether the corresponding tomographic plane corresponding to the tomographic image in which each of the plurality of feature points is detected is a focal plane, and
• derive a positional shift amount between the plurality of projection images based on body movement of the subject with the feature point as a reference on a corresponding tomographic plane which is discriminated to be the focal plane.

A tomographic image generating apparatus comprising at least one processor,

• wherein the processor is configured to:
• acquire a plurality of projection images corresponding to a plurality of radiation source positions, the plurality of projection images being generated by causing an imaging apparatus to perform tomosynthesis imaging in which a radiation source is moved relative to a detection surface of a radiation detector in order to emit radiation to a subject at the plurality of radiation source positions according to movement of the radiation source;
• reconstruct all or a part of the plurality of projection images to generate a tomographic image on each of a plurality of tomographic planes of the subject;
• detect at least one feature point from a plurality of the tomographic images;
• and
• derive a positional shift amount between the plurality of projection images based on body movement of the subject with the feature point as a reference on a corresponding tomographic plane corresponding to the tomographic image in which the feature point is detected,
• wherein the processor is further configured to reconstruct the plurality of projection images by correcting the positional shift amount to generate a corrected tomographic image on at least one tomographic plane of the subject, and
• wherein the processor is further configured to perform image quality evaluation for a region of interest including the feature point in the corrected tomographic image, and determines whether the derived positional shift amount is appropriate or inappropriate based on a result of the image quality evaluation.

A tomographic image generating apparatus comprising at least one processor,

• wherein the processor is configured to:
• acquire a plurality of projection images corresponding to a plurality of radiation source positions, the plurality of projection images being generated by causing an imaging apparatus to perform tomosynthesis imaging in which a radiation source is moved relative to a detection surface of a radiation detector in order to emit radiation to a subject at the plurality of radiation source positions according to movement of the radiation source;
• reconstruct all or a part of the plurality of projection images to generate a tomographic image on each of a plurality of tomographic planes of the subject;
• detect at least one feature point from a plurality of the tomographic images;
• and
• derive a positional shift amount between the plurality of projection images based on body movement of the subject with the feature point as a reference on a corresponding tomographic plane corresponding to the tomographic image in which the feature point is detected,
• wherein the processor is further configured to reconstruct the plurality of projection images by correcting the positional shift amount to generate a corrected tomographic image on at least one tomographic plane of the subject, and
• wherein the processor is further configured to derive an evaluation function for performing image quality evaluation for a region of interest including the feature point in the corrected tomographic image, and
• derive the positional shift amount for optimizing the evaluation function.

A tomographic image generating apparatus comprising at least one processor,

• wherein the processor is configured to:
• acquire a plurality of projection images corresponding to a plurality of radiation source positions, the plurality of projection images being generated by causing an imaging apparatus to perform tomosynthesis imaging in which a radiation source is moved relative to a detection surface of a radiation detector in order to emit radiation to a subject at the plurality of radiation source positions according to movement of the radiation source;
• reconstruct all or a part of the plurality of projection images to generate a tomographic image on each of a plurality of tomographic planes of the subject;
• detect at least one feature point from a plurality of the tomographic images;
• and
• derive a positional shift amount between the plurality of projection images based on body movement of the subject with the feature point as a reference on a corresponding tomographic plane corresponding to the tomographic image in which the feature point is detected,
• wherein the subject is a breast, and
• wherein the processor is further configured to change a search range in a case of deriving the positional shift amount depending on at least one of a density of a mammary gland, a size of the breast, an imaging time of the tomosynthesis imaging, a compression pressure of the breast in a case of the tomosynthesis imaging, or an imaging direction of the breast.

A tomographic image generating method comprising:

• acquiring a plurality of projection images corresponding to a plurality of radiation source positions, the plurality of projection images being generated by causing an imaging apparatus to perform tomosynthesis imaging in which a radiation source is moved relative to a detection surface of a radiation detector in order to emit radiation to a subject at the plurality of radiation source positions according to movement of the radiation source;
• reconstructing all or a part of the plurality of projection images to generate a tomographic image on each of a plurality of tomographic planes of the subject;
• detecting a plurality of feature point from a plurality of the tomographic images;
• discriminating whether the corresponding tomographic plane corresponding to the tomographic image in which each of the plurality of feature points is detected is a focal plane, and
• deriving a positional shift amount between the plurality of projection images based on body movement of the subject with the feature point as a reference on a corresponding tomographic plane which is discriminated to be the focal plane.

A non-transitory computer-readable storage medium that stores a tomographic image generating program causing a computer to execute:

• a step of acquiring a plurality of projection images corresponding to a plurality of radiation source positions, the plurality of projection images being generated by causing an imaging apparatus to perform tomosynthesis imaging in which a radiation source is moved relative to a detection surface of a radiation detector in order to emit radiation to a subject at the plurality of radiation source positions according to movement of the radiation source;
• a step of reconstructing all or a part of the plurality of projection images to generate a tomographic image on each of a plurality of tomographic planes of the subject;
• a step of detecting a plurality of feature point from a plurality of the tomographic images;
• a step of discriminate whether the corresponding tomographic plane corresponding to the tomographic image in which each of the plurality of feature points is detected is a focal plane, and
• a step of deriving a positional shift amount between the plurality of projection images based on body movement of the subject with the feature point as a reference on a corresponding tomographic plane which is discriminated to be the focal plane.