Miniaturized photoacoustic imaging apparatus including a rotatable reflector

• US 9,351,705 B2
• Filed: 01/08/2010
• Issued: 05/31/2016
• Est. Priority Date: 01/09/2009
• Status: Active Grant

• Current Assignee: Washington University In St Louis
• Original Assignee: Washington University In St Louis
• Inventors: Wang, Lihong, Maslov, Konstantin, Yang, Joon-Mo
• Primary Examiner(s): Lamprecht, Joel
• Application Number:
  US13/143,832
• Publication Number:
  US 20110275890A1
• Time in Patent Office: 2,335 Days
• US Class Current: 1/1
• CPC Class Codes: A61B 5/0062 Arrangements for scanning
• CPC Class Codes: A61B 5/0068 Confocal scanning
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: A61B 5/0095 by applying light and detecting acoustic waves, i.e. photoacoustic measurements
• CPC Class Codes: A61B 5/08 Detecting, measuring or recording devices for evaluating the respiratory organs A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/0873 using optical means
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: A61B 8/4461 Features of the scanning mechanism, e.g. for moving the transducer within the housing of the probe

Abstract

A reflection-mode photoacoustic endoscope includes a light source configured to emit a light pulse, a signal detection or transmission unit configured to detect or emit an ultrasonic pulse, and a rotatable reflector. The rotatable reflector is configured to reflect at least one of the light pulse and the ultrasonic pulse into a target area of an object, and reflect a response signal to the signal detection unit. The response signal is one of a photoacoustic wave generated by the object responsive to the light pulse and an ultrasonic pulse echo generated by the object responsive to the ultrasonic pulse.

Claims

1. A reflection-mode photoacoustic endoscope comprising:

a tube;

a light source configured to emit a light pulse suitable for photoacoustic imaging;

a signal detection or detection and transmission unit configured to detect or emit and detect an ultrasonic pulse; and

a reflector rotatable relative to said tube and configured to;

reflect the light pulse and the ultrasonic pulse into a target area of an object; and

reflect a response signal to said signal detection unit, the response signal being one of a photoacoustic wave generated by the object responsive to the light pulse and an ultrasonic pulse echo generated by the object responsive to the ultrasonic pulse.

2. A reflection-mode photoacoustic endoscope in accordance with claim 1, further comprising a micromotor coupled at a first end to said reflector, said micromotor configured to impart a rotational force on said reflector.

3. A reflection-mode photoacoustic endoscope in accordance with claim 2, wherein said micromotor comprises a galvanometer lead.

4. A reflection-mode photoacoustic endoscope in accordance with claim 2, wherein said micromotor comprises a plurality of gears.

5. A reflection-mode photoacoustic endoscope in accordance with claim 2, wherein said micromotor is coupled at a second end to a gear mechanism.

6. A reflection-mode photoacoustic endoscope in accordance with claim 1, further comprising a micromotor and a magnet assembly, said magnet assembly coupled to said reflector.

7. A reflection-mode photoacoustic endoscope in accordance with claim 6, wherein said magnet assembly comprises a first magnet coupled to said micromotor and a second magnet positioned with respect to said first magnet and coupled to said reflector, said micromotor configured to generate torque, said first magnet configured to convert the torque into a magnetic field, said second magnet configured to rotate said reflector based on the magnetic field.

8. A reflection-mode photoacoustic endoscope in accordance with claim 1, wherein said signal detection unit comprises an ultrasonic transducer, said reflector comprises a parabolic mirror configured to reflect and focus the response signal onto said ultrasonic transducer.

9. A reflection-mode photoacoustic endoscope in accordance with claim 1, wherein said reflector comprises a plurality of reflective surfaces.

10. A reflection-mode photoacoustic endoscope in accordance with claim 1, wherein said endoscope is sized to fit within a catheter.

11. An endoscopy system comprising:

a reflection-mode photoacoustic endoscope comprising;

a tube;

a light source configured to emit a light pulse suitable for photoacoustic imaging;

a signal detection or transmission unit configured to detect or emit an ultrasonic pulse; and

a mirror rotatable relative to said tube configured to reflect the light pulse and the ultrasonic pulse into a target area of an object, and reflect a response signal to said signal detection unit, the response signal being one of a photoacoustic wave generated by the object responsive to the light pulse and an ultrasonic pulse echo generated by the object responsive to the ultrasonic pulse;

a data-acquisition system configured to receive an electronic signal generated by said signal detection unit based on the response signal; and

a data-analysis computer configured to generate an image based on the electronic signal.

12. An endoscopy system in accordance with claim 11, wherein said endoscope further comprises a micromotor coupled at a first end to said mirror, said micromotor configured to impart a rotational force on said mirror.

13. An endoscopy system in accordance with claim 11, wherein said endoscope further comprises a micromotor and a magnet assembly, said magnet assembly coupled to said mirror.

14. An endoscopy system in accordance with claim 13, wherein said magnet assembly comprises a first magnet coupled to said micromotor and a second magnet positioned with respect to said first magnet and coupled to said mirror, said micromotor configured to generate torque, said first magnet configured to convert the torque into a magnetic field, said second magnet configured to rotate said mirror based on the magnetic field.

15. An endoscopy system in accordance with claim 11, wherein said signal detection unit comprises an ultrasonic transducer, said mirror comprises a parabolic mirror configured to reflect and focus the response signal onto said ultrasonic transducer.

16. An endoscopy system in accordance with claim 11, wherein said mirror comprises a plurality of reflective surfaces.

17. An endoscopy system in accordance with claim 11, wherein said endoscope is sized to fit within a catheter.

18. An endoscopy scanning method comprising:

emitting a light pulse and an ultrasonic pulse;

reflecting the pulses into an object using a mirror rotatable relative to a tube such that a response signals are emitted by the object responsive to the pulses;

reflecting the response signals, by the mirror, to a signal detection unit, the response signals being a photoacoustic wave generated by the object in response to the light pulse and an ultrasonic pulse echo generated by the object in response to the ultrasonic pulse;

generating electronic signals based on the response signals; and

generating an image based on the electronic signals.

19. An endoscopy scanning method in accordance with claim 18, further comprising rotating the mirror using a micromotor coupled to a plurality of gears.

20. An endoscopy scanning method in accordance with claim 18, further comprising rotating the mirror using a micromotor coupled to a magnet assembly.