Photoacoustic imaging apparatus, photoacoustic imaging method, and program for executing photoacoustic imaging method

Abstract

An optical property distribution, such as an absorption coefficient of the inside of a subject, is highly precisely acquired. A photoacoustic imaging apparatus includes an acoustic converting unit configured to receive acoustic waves generated by irradiating a subject with emitted light and to convert the acoustic wave to an electrical signal; and a processing unit configured to determine a light intensity distribution inside the subject on the basis of a light intensity distribution or an illuminance distribution of the light incident on the surface of the subject and to generate image data on the basis of the electrical signal and the determined light intensity distribution inside the subject.

1 . A processing apparatus that acquires subject information by using a signal derived from an acoustic wave generated by irradiating a subject a shape of which is defined by a container with light, comprising:
 a storage unit configured to store pieces of information regarding illuminance distribution on a surface of the subject;   a reading unit configured to read, out of the storage unit, information regarding illuminance distribution corresponding to the container among the pieces of information regarding illuminance distribution; and   an acquisition unit configured to, based on the information regarding illuminance distribution corresponding to the container and based on the signal, acquire the subject information.   
     
     
         2 . The processing apparatus according to  claim 1 ,
 wherein, based on the information regarding illuminance distribution corresponding to the container, the acquisition unit acquires information regarding light intensity distribution inside the subject, and   wherein, based on the information regarding light intensity distribution inside the subject and based on the signal, the acquisition unit acquires the subject information.   
     
     
         3 . The processing apparatus according to  claim 2 ,
 wherein, based on the information regarding illuminance distribution corresponding to the container, the acquisition unit places an imaginary light source corresponding to the illuminance distribution in a calculation space, and acquires the information regarding light intensity distribution inside the subject by calculating propagation of light inside the subject from the imaginary light source.   
     
     
         4 . The processing apparatus according to  claim 3 ,
 wherein the acquisition unit acquires the information regarding light intensity distribution inside the subject by calculating the propagation of light inside the subject from the imaginary light source by using a light diffusion equation, a transport equation, or a Monte Carlo simulation for light propagation.   
     
     
         5 . The processing apparatus according to  claim 2 ,
 wherein, based on the signal, the acquisition unit acquires information regarding optical-energy-absorption density distribution or initial-acoustic-pressure distribution inside the subject, and   wherein, based on the information regarding optical-energy-absorption density distribution or initial-acoustic-pressure distribution and based on the information regarding illuminance distribution corresponding to the container, the acquisition unit acquires the subject information.   
     
     
         6 . The processing apparatus according to  claim 5 ,
 wherein the subject information is information regarding absorption-coefficient distribution.   
     
     
         7 . The processing apparatus according to  claim 1 ,
 wherein the storage unit stores pieces of information regarding illuminance distribution corresponding to a plurality of containers, inclusive of the information regarding illuminance distribution corresponding to the container.   
     
     
         8 . The processing apparatus according to  claim 1 ,
 wherein the reading unit reads information regarding illuminance distribution corresponding to a size or a shape of the container.   
     
     
         9 . The processing apparatus according to  claim 1 , further comprising:
 a display control unit configured to cause a display to display an image that is based on the subject information.   
     
     
         10 . A processing apparatus that acquires subject information by using a signal derived from an acoustic wave generated by irradiating a subject a shape of which is defined by a container with light, comprising:
 a storage unit configured to store pieces of information regarding light intensity distribution inside the subject;   a reading unit configured to read, out of the storage unit, information regarding light intensity distribution corresponding to the container among the pieces of information regarding light intensity distribution; and   an acquisition unit configured to, based on the information regarding light intensity distribution corresponding to the container and based on the signal, acquire the subject information.   
     
     
         11 . The processing apparatus according to  claim 10 ,
 wherein, based on the signal, the acquisition unit acquires information regarding optical-energy-absorption density distribution or initial-acoustic-pressure distribution inside the subject, and   wherein, based on the information regarding optical-energy-absorption density distribution or initial-acoustic-pressure distribution and based on the information regarding illuminance distribution corresponding to the container, the acquisition unit acquires the subject information.   
     
     
         12 . The processing apparatus according to  claim 11 ,
 wherein the subject information is information regarding absorption-coefficient distribution.   
     
     
         13 . The processing apparatus according to  claim 10 ,
 wherein the storage unit stores pieces of information regarding light intensity distribution corresponding to a plurality of containers, inclusive of the information regarding light intensity distribution corresponding to the container.   
     
     
         14 . The processing apparatus according to  claim 10 ,
 wherein the reading unit reads information regarding light intensity distribution corresponding to a size or a shape of the container.   
     
     
         15 . A processing method for acquiring subject information by using a signal derived from an acoustic wave generated by irradiating a subject a shape of which is defined by a container with light, comprising:
 reading, out of a storage unit configured to store pieces of information regarding illuminance distribution on a surface of the subject, information regarding illuminance distribution corresponding to the container; and   acquiring, based on the information regarding illuminance distribution corresponding to the container and based on the signal, the subject information.   
     
     
         16 . A processing method for acquiring subject information by using a signal derived from an acoustic wave generated by irradiating a subject a shape of which is defined by a container with light, comprising:
 reading, out of a storage unit configured to store pieces of information regarding light intensity distribution inside the subject, information regarding light intensity distribution corresponding to the container; and   acquiring, based on the information regarding light intensity distribution corresponding to the container and based on the signal, the subject information.   
     
     
         17 . A processing method, comprising:
 acquiring image data that is based on a signal derived from an acoustic wave generated by irradiating a subject with light;   acquiring, based on the image data, information regarding a shape of the subject;   acquiring, based on the information regarding a shape of the subject and based on intensity distribution of the light with which the subject is irradiated, information regarding illuminance distribution of the light with which the subject is irradiated on a surface of the subject; and   acquiring, based on the information regarding illuminance distribution on the surface of the subject and based on the signal, the subject information.   
     
     
         18 . A non-transitory computer-readable storage medium storing a program for causing a computer to execute processes of the processing method according to  claim 15 .