PET-CT apparatus, medical image processing method, and non-transitory computer-readable medium

1 . A PET-CT apparatus, comprising:

a CT scanner configured to scan a subject to acquire CT scan data;

a PET scanner configured to detect a gamma ray emitted from the subject to acquire PET scan data; and

processing circuitry configured to:

acquire camera data obtained by a camera configured to scan the subject while the CT scanner scans the subject and configured to scan the subject while the PET scanner detects the gamma ray;

generate correction data for attenuation correction based on the CT scan data;

identify, based on the camera data, a respiratory phase of the subject corresponding to the CT scan data that is used for generating the correction data;

exclude a first period from the PET scan data based on the camera data, the first period being a period during which a movement of the subject that is different from a respiration of the subject occurs while the PET scanner detects the gamma ray;

identify a second period in the PET scan data from which the first period has been excluded, the second period corresponding to the identified respiratory phase;

and

reconstruct a PET image based on the generated correction data and a part of the PET scan data corresponding to the second period.

2 . The PET-CT apparatus according to claim 1 , wherein the processing circuitry is further configured to:

acquire a respiratory waveform from the camera data in which respiratory dynamics of the subject are recorded; and

identify the respiratory phase based on the respiratory waveform.

3 . The PET-CT apparatus according to claim 1 , wherein the camera is an infrared camera that visualizes infrared emitted from the subject.

4 . The PET-CT apparatus according to claim 1 , wherein the camera is a terahertz camera that visualizes a terahertz-band electromagnetic wave emitted from the subject.

5 . The PET-CT apparatus according to claim 1 , wherein the camera is an optical camera that captures an image of a marker placed on a body of the subject.

6 . The PET-CT apparatus according to claim 1 , wherein a part of the CT scan data corresponding to another respiratory phase different from the respiratory phase identified based on the camera data is not used for the generation of the correction data.

7 . A medical image processing method, comprising:

scanning a subject with a CT scanner to acquire CT scan data;

detecting, by a PET scanner, a gamma ray emitted from the subject to acquire PET scan data;

acquiring camera data obtained by a camera configured to scan the subject while the CT scanner scans the subject and configured to scan the subject while the PET scanner detects the gamma ray;

generating correction data for attenuation correction based on the CT scan data;

identifying, based on the camera data, a respiratory phase of the subject corresponding to the CT scan data that is used for generating the correction data;

excluding a first period from the PET scan data based on the camera data, the first period being a period during which a movement of the subject that is different from a respiration of the subject occurs while the PET scanner detects the gamma ray;

identifying a second period in the PET scan data from which the first period has been excluded, the second period corresponding to the identified respiratory phase;

and

reconstructing a PET image based on the generated correction data and a part of the PET scan data corresponding to the second period.