Biological information imaging apparatus and method for analyzing biological information

• US 9,131,851 B2
• Filed: 02/04/2009
• Issued: 09/15/2015
• Est. Priority Date: 02/06/2008
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Fukutani, Kazuhiko, Nakajima, Takao, Asao, Yasufumi
• Primary Examiner(s): FERNANDEZ, KATHERINE L
• Application Number:
  US12/365,237
• Publication Number:
  US 20090198128A1
• Time in Patent Office: 2,414 Days
• Field of Search: 600/407, 600/437, 600/438, 600/476
• US Class Current: 1/1
• CPC Class Codes: A61B 5/0091 for mammography
• CPC Class Codes: A61B 5/0095 by applying light and detecting acoustic waves, i.e. photoacoustic measurements
• CPC Class Codes: A61B 5/4312 Breast evaluation or disorder diagnosis A61B5/0091 takes precedence
• CPC Class Codes: A61B 5/4887 Locating particular structures in or on the body
• CPC Class Codes: A61B 5/489 Blood vessels
• CPC Class Codes: A61B 8/0825 for diagnosis of the breast, e.g. mammography
• CPC Class Codes: A61B 8/4416 related to combined acquisition of different diagnostic modalities, e.g. combination of ultrasound and X-ray acquisitions
• CPC Class Codes: A61B 8/5223 for extracting a diagnostic or physiological parameter from medical diagnostic data for algorithms to analyse biomedical images G06T7/0012
• CPC Class Codes: G01N 29/2418 using optoacoustic interaction with the material, e.g. laser radiation, photoacoustics photoacoustic cells G01N21/1702; measuring characteristics of vibrations by using radiation-sensitive means G01H9/00; acousto-optical conversion techniques for short-range imaging G01S15/8965; sound-producing devices using laser bundle G10K15/046

Abstract

There are provided a biological information imaging apparatus that can measure ultrasound generated from an optical absorber in a deep part of a subject living body with high sensitivity, and a method for analyzing biological information using the biological information imaging apparatus. The biological information imaging apparatus that detects ultrasound and images biological information, includes: a light source that irradiates the subject with light for generating ultrasound from an optical absorber existing in the subject; an ultrasound transmission unit that transmits focused ultrasound to a specific region where the optical absorber exists; and an ultrasound detection unit that detects an ultrasound synthesized signal due to interaction between ultrasound generated from the optical absorber that absorbs the light and the focused ultrasound transmitted to the specific region.

Claims

1. An apparatus that detects ultrasound comprising:

a light source configured to irradiate a subject with light;

an ultrasound transmission unit configured to transmit a first focused ultrasound to a specific region in the subject while the subject is not irradiated with the light from said light source and a second focused ultrasound to the specific region while the subject is irradiated with the light from said light source;

an ultrasound detection unit configured to detect a reflection ultrasound or a transmission ultrasound of the first focused ultrasound and to output a signal in response to said detection, wherein said ultrasound detection unit is further configured to detect an overlapped ultrasound in which a photoacoustic wave generated by irradiating the subject with the light and a reflection ultrasound or a transmission ultrasound of the second focused ultrasound are overlapped and to further output an overlapped ultrasound signal in response to said detection of said overlapped ultrasound; and

a signal processing unit configured to obtain a difference signal corresponding to an intensity difference between intensity of the overlapped ultrasound signal and intensity of the signal.

2. The apparatus according to claim 1, wherein said ultrasound detection unit and said ultrasound transmission unit form an ultrasound transmission/detection unit,

wherein said ultrasound transmission/detection unit is configured to transmit the first and second focused ultrasounds, and

wherein said ultrasound transmission/detection unit is configured to detect the reflection ultrasound of the first focused ultrasound.

3. The apparatus according to claim 1, wherein said ultrasound detection unit or said ultrasound transmission unit includes a plurality of ultrasound transducers arranged two-dimensionally.

4. The apparatus according to claim 1, wherein said ultrasound transmission unit or said ultrasound detection unit includes capacitance transducers.

5. The apparatus according to claim 1, wherein said ultrasound detection unit is arranged in a region including a surface of the subject.

6. The apparatus according to claim 1, wherein said light source is a pulsed-light source that outputs pulsed light.

7. The apparatus according to claim 6, wherein said pulsed-light source outputs the pulsed light having a wavelength of 400 nm to 1600 nm.

8. The apparatus according to claim 6, wherein a time width of the pulsed light is 100 picoseconds to 500 nanoseconds.

9. The apparatus according to claim 1, wherein the signal processing unit is configured to obtain information on an optical property value of the specific region based on the difference signal.

10. The apparatus according to claim 1, wherein said ultrasound transmission unit is configured to transmit the first focused ultrasound such that a frequency of the first focused ultrasound is continuously changed.

11. The apparatus according to claim 1, wherein said ultrasound transmission unit is configured to transmit the first and second focused ultrasounds such that waveforms of the first and second focused ultrasounds have a plurality of frequencies.

12. A method comprising the steps of:

transmitting a first focused ultrasound to a specific region in a subject while the subject is not irradiated with light from a light source;

detecting a reflection ultrasound or a transmission ultrasound of the first focused ultrasound and outputting a signal in response to said detection;

irradiating the subject with the light;

transmitting a second focused ultrasound to the specific region in the subject while the subject is irradiated with the light;

detecting an overlapped ultrasound in which a photoacoustic wave generated by irradiating the subject with the light and a reflection ultrasound or a transmission ultrasound of the second focused ultrasound are overlapped and outputting an overlapped ultrasound signal in response to said detection of said overlapped ultrasound; and

obtaining a difference signal corresponding to an intensity difference between intensity of the overlapped ultrasound signal and intensity of the signal.

13. The method for detecting ultrasound according to claim 12, wherein the light is pulsed light.

14. The method for detecting ultrasound according to claim 13, wherein a time width of the pulsed light is 100 picoseconds to 500 nanoseconds.

15. The method for detecting ultrasound according to claim 12, wherein a frequency of the second focused ultrasound is continuously changed.

16. The method for detecting ultrasound according to claim 12, further comprising obtaining information on an optical characteristic value of the specific region based on the difference signal.

17. The method for detecting ultrasound according to claim 12, wherein the specific region is scanned in the subject to repeat measurement to obtain a three-dimensional optical characteristic value distribution in the subject.

18. The method for detecting ultrasound according to claim 12, wherein waveforms of the first and second focused ultrasounds have a plurality of frequencies.