Photoacoustic and thermoacoustic tomography for breast imaging

Abstract

A system for imaging a biological sample including a tubular body having a side wall defining an interior shaped and sized for receiving the biological sample, an electromagnetic source positioned at one end of the tubular body interior for directing electromagnetic energy into the biological sample in the body interior, and an ultrasonic transducer positioned along said side wall of the body for receiving ultrasonic energy induced by the electromagnetic energy and transmitted through the biological sample.

1 - 24 . (canceled) 
     
     
         25 . A method of acquiring a plurality of photoacoustic signals for imaging a human breast, the method comprising:
 providing a system comprising a cylindrical body with an inner wall extending along a longitudinal axis of the cylindrical body and defining an interior, an electromagnetic source, an array of ultrasound transducers positioned radially outward from the inner wall and opposite the interior, and a cylindrical mount moveably mounted around the cylindrical body, wherein the array of ultrasound transducers is mounted to the cylindrical mount;   receiving and confining the human breast within the interior of the cylindrical body;   advancing the cylindrical mount to a plurality of scanning positions; and   at each position of the plurality of scanning positions:
 producing a pulse of electromagnetic energy using the electromagnetic source; 
 directing the pulse of electromagnetic energy into the interior; and 
 receiving a plurality of induced ultrasonic signals at the array of ultrasound transducers, the plurality of induced ultrasonic signals produced by the human breast within the interior. 
   
     
     
         26 . The method of  claim 25 , wherein advancing the cylindrical mount to a plurality of scanning positions further comprises rotating the cylindrical mount about the longitudinal axis of the cylindrical body. 
     
     
         27 . The method of  claim 26 , wherein the array of ultrasound transducers is mounted to the cylindrical mount in a linear pattern, the linear pattern extending parallel to the longitudinal axis of the cylindrical body. 
     
     
         28 . The method of  claim 26 , wherein the array of ultrasound transducers is mounted to the cylindrical mount in a helical pattern. 
     
     
         29 . The method of  claim 25 , wherein advancing the cylindrical mount to a plurality of scanning positions further comprises translating the cylindrical mount along the cylindrical body in a direction parallel to the longitudinal axis of the cylindrical body. 
     
     
         30 . The method of  claim 29 , wherein the array of ultrasound transducers is mounted to the cylindrical mount in a ring pattern. 
     
     
         31 . The method of  claim 25 , wherein the pulse of electromagnetic energy comprises a wavelength in one of a radiofrequency band, a microwave band, a visible light band, and an infrared light band. 
     
     
         32 . The method of  claim 31 , further comprising at each position of the plurality of scanning positions:
 producing a second pulse of electromagnetic energy using the electromagnetic source, wherein the second pulse of electromagnetic energy comprises a second wavelength;   directing the second pulse of electromagnetic energy into the interior; and   receiving a second plurality of induced ultrasonic signals at the array of ultrasound transducers, the second plurality of induced ultrasonic signals produced by the human breast within the interior; wherein:
 the second pulse of electromagnetic energy comprises a second wavelength in one of the radiofrequency band, the microwave band, the visible light band, and the infrared light band; and 
 the second wavelength of the second pulse of electromagnetic energy is different from the wavelength of the pulse of electromagnetic energy. 
   
     
     
         33 . The method of  claim 32 , wherein the wavelength and the second wavelength are in one of the visible light band and the infrared light band. 
     
     
         34 . The method of  claim 32 , wherein the wavelength is in the microwave band and the second wavelength is in one of the visible light band and the infrared light band. 
     
     
         35 . The method of  claim 25 , wherein:
 the system further comprises a piston slideably mounted within the interior of the cylindrical body; and   receiving and confining the human breast within the interior of the cylindrical body further comprises sliding the piston upward to compress the human breast against a chest wall positioned over the cylindrical body.   
     
     
         36 . The method of  claim 25 , wherein:
 the system further comprises a vacuum pump operatively coupled to a passage formed through the cylindrical body into the interior; and   receiving and confining the human breast within the interior of the cylindrical body further comprises removing air from the interior using the vacuum pump.