Breast cancer detection, imaging and screening by electromagnetic millimeter waves

• US 5,807,257 A
• Filed: 04/17/1997
• Issued: 09/15/1998
• Est. Priority Date: 07/01/1994
• Status: Expired due to Term

• Current Assignee: Interstitial, LLC
• Original Assignee: Interstitial, Inc.
• Inventors: Bridges, Jack E.
• Primary Examiner(s): CASLER, BRIAN L
• Application Number:
  US08/843,858
• Time in Patent Office: 516 Days
• Field of Search: 600/407, 600/430, 600/310, 600/473, 600/476, 600/437, 600/438, 600/442, 600/2, 606/2, 606/12, 606/33, 128/915, 607/100, 607/101, 607/97, 607/154, 250/330-334, 250/358.1
• US Class Current: 600/430
• CPC Class Codes: A61B 5/05 Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves impedance plethysmography A61B5/0295; measuring movement of the entire body or parts thereof A61B5/11; detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof A61B5/24
• CPC Class Codes: A61B 5/0507 using microwaves or terahertz waves
• CPC Class Codes: A61B 5/4312 Breast evaluation or disorder diagnosis A61B5/0091 takes precedence
• CPC Class Codes: A61B 6/0435 with means for imaging suspended breasts
• CPC Class Codes: A61B 6/502 for diagnosis of breast, i.e. mammography

Abstract

A method for detecting an incipient tumor in living tissue such as that of a human breast in accordance with differences in relative dielectric characteristics. A generator produces a non-ionizing electromagnetic input wave of preselected frequency, usually exceeding three gigahertz, and that input wave is used to illuminate the living tissue, being effectively focused into a small, discrete volume within the tissue to develop a non-ionizing electromagnetic wave at that position. The illumination location is moved over a portion of the living tissue in a predetermined scanning pattern. Scattered signal returns collected from the living tissue are collected to develop a scatter return signal. The scatter return signal is employed to detect any anomaly, caused by differences in relative dielectric characteristics, that maybe indicative of the presence of a tumor in the scanned living tissue.

Claims

1. A method to detect the presence of a tumor or an incipient tumor in the tissue of a living organism, such as in the tissue of a human breast, in which non-tumor tissue has a predetermined dielectric characteristic different from the corresponding dielectric characteristic of a tumor, the method comprising the following steps:

A. generating a non-ionizing electromagnetic input wave of preselected frequency having a large bandwidth;

B. illuminating the tissue of a living organism with the input wave of step A, effectively focused into a beam impinging upon a first small, discrete volume at a predetermined illumination position within the tissue to develop a non-ionizing electromagnetic wave at that illumination position;

C. moving the illumination position of step B over a preselected portion of the tissue in a predetermined scanning pattern;

D. collecting scattered returns from the tissue while it is being scanned in step C to develop a scattered return signal; and

E. processing the scattered return signal of step D to detect any anomaly in that signal indicative of the presence of a tumor in the scanned tissue.

2. A method of detecting a tumor in the tissue of a living organism, according to claim 1, in which, in step E, the scattered return signal of step D is processed to form a three dimensional image of a tumor.

3. A method of detecting a tumor in the tissue of a living organism, according to claim 1, including the following additional step:

X. controlling the input wave of step B and the scattered return signal of step D to separate the scattered return signal from the input wave.

4. A method of detecting a tumor in the tissue of a living organism, according to claim 1, in which the scattered returns of step D are polarized differently from the input wave of step A, and in which polarization of the scattered returns of step D are utilized to enhance the reliability of detecting the presence of a tumor.

5. A method of detecting a tumor in the tissue of a living organism, according to claim 1, in which tumor-induced resonant anomalies in the scattered returns of step D are utilized to enhance the reliability of detecting the presence of a tumor.

6. A method of detecting a tumor in the tissue of a living organism, according to claim 1, in which tumor-induced anomalies in the direction of scatter, such as, forward scatter or side scatter, are utilized to enhance the reliability of detecting the presence of a tumor.

7. A method of detecting a tumor in the tissue of a living organism, according to claim 1, in which, in step E, the scattered return signals of step D taken at one time are compared with the scattered return signals of step D taken at a different time.

8. A method of detecting a tumor in the tissue of a living organism, according to claim 1, in which, in step E, the scattered return signals of step D taken from one breast are compared with the scattered return signals of step D taken from the opposite breast.

9. A method of detecting a tumor in the tissue of a living organism, according to claim 1, in which, in step B, the effective focussing of the input wave (step B) is performed by a wave guide array including a plurality of wave guides each in contact with the facing tissue.

10. A method of detecting a tumor in the tissue of a living organism, according to claim 9, in which the movement of step C is performed electronically by changing the phase of the input wave supplied to each of the wave guides in the wave guide array.

11. A method of detecting a tumor in the tissue of a living organism, according to claim 9, in which the movement of step C is performed by changing the timing of the input wave supplied to each of the wave guides in the wave guide array.

12. A method of detecting a tumor in the tissue of a living organism, according to claim 1, in which the movement of step C is performed mechanically.

13. A method of detecting a tumor in the tissue of a living organism, according to claim 1, in which step D includes:

D1. collecting scattered returns from the surface of the tissue;

D2. collecting scattered returns from the small, discrete volume at the predetermined illumination position within the tissue into which the beam is effectively focussed in step B; and

D3. combining the scattered returns of steps D1 and D2 to add constructively to each other to develop a scattered return signal.

14. A method of detecting a tumor in the tissue of a living organism, according to claim 13, in which the illuminating wave of step B is separated from the surface returns of step D1.

15. A method to detect the presence of a tumor or an incipient tumor in the tissue of a living organism, such as in the tissue of a human breast, in which non-tumor tissue has a predetermined dielectric characteristic different from the corresponding dielectric characteristic of a tumor, the method comprising the following steps:

AA. generating a non-ionizing pulsed electromagnetic input wave having a large bandwidth;

BB. effectively focusing the pulsed electromagnetic input wave into a selected focal point in the tissue that may contain a potential tumor;

CC. collecting electromagnetic energy scattered by a tumor in the tissue by a collector that has the same in-tissue focal point as step BB;

DD. scanning the common in-tissue focal point of steps BB and CC at preselected volumes within the tissue;

EE. separating tumor returns from the impinging wave forms and from scattering sources of no interest; and

FF. processing the collected energy of step CC to detect any anomaly that indicates the presence of a tumor within the scanned tissue.

16. The method of claim 15 in which the separation of the desired tumor returns of step EE is by a passive method.

17. The method of claim 16 in which said passive method is polarization.

18. The method of claim 16 in which the separation of the desired tumor returns of step EE is by an active method.

19. The method of claim 15 in which the processing of step FF includes the step of suppressing scattering that does not originate from the common focal point of step CC.

20. The method of claim 15 in which separation of tumor returns as set forth in step EE includes the step of suppressing scattering that does not arrive at the collector of step CC at the same time said scattering arrives from a possible tumor site.

21. The method of claim 15 in which the scanning of the common in-tissue focal point of steps BB and CC as set forth in step DD includes the step of electronically scanning the common focal point of steps BB and CC by controlling the timing of the wave forms that are applied to or received from a set of waveguide aperture antenna locations on the surface of the skin of the tissue.

22. The method of claim 15 in which separating tumor return is set forth in step EE includes the step of comparing past examination results with current examination results.

23. The method of claim 15 in which the step of separating tumor results includes comparing results from adjacent breasts of one human.

24. The method of claim 15 in which separation of tumor returns as set forth in step EE includes the step of providing a known location for wave guide aperture antennas.

25. The method of claim 15 where the focusing of step BB is accomplished by an illuminator in contact with breast tissue.

26. The method of claim 15 in which the focusing of step BB is accomplished by an illuminator which is also the collector.

27. The method of claim 26 in which the focussed illumination of step BB and the collection of step CC are accomplished by a synthetic aperture.