Diagnostic apparatus utilizing radiation interaction with biological tissue

• US 6,123,719 A
• Filed: 04/23/1998
• Issued: 09/26/2000
• Est. Priority Date: 10/24/1995
• Status: Expired due to Fees

• Current Assignee: Rosslyn Medical Limited (Jordans Nominees (Cyprus) Ltd.)
• Original Assignee: Rosslyn Medical Limited (Jordans Nominees (Cyprus) Ltd.)
• Inventors: Masychev, Victor
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US09/065,031
• Time in Patent Office: 887 Days
• Field of Search: 600/310, 600/312, 600/321, 600/342, 600/407
• US Class Current: 600/407
• CPC Class Codes: A61B 18/245 for removing obstructions in blood vessels or calculi
• CPC Class Codes: A61B 2560/0233 Optical standards
• CPC Class Codes: A61B 2562/0242 for varying or adjusting the optical path length in the tissue
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/0062 Arrangements for scanning
• CPC Class Codes: A61B 5/0073 by tomography, i.e. reconstruction of 3D images from 2D projections A61B5/0066 takes precedence
• CPC Class Codes: A61B 5/444 Evaluating skin marks, e.g. mole, nevi, tumour, scar
• CPC Class Codes: A61B 5/445 Evaluating skin irritation or skin trauma, e.g. rash, eczema, wound, bed sore
• CPC Class Codes: A61B 6/508 for non-human patients
• CPC Class Codes: A61N 5/062 Photodynamic therapy, i.e. excitation of an agent

Abstract

A diagnostic apparatus comprises a source (1) of probing electromagnetic radiation and means (2) for transmitting the output from the probing radiation source (1) to biological tissue (3) to be examined. The apparatus also comprises means (4, 41) for detecting probing radiation reflected from the tissue (3) and stimulated radiation resulting from excitation of the tissue (3) by the probing radiation. A processing means (5-9) responsive to the reflected and stimulated radiations to produce a signal for diagnosis of the condition of the tissue and means (15, 16) for regulating the intensity of the probing radiation including a feedback circuit (16, 17, 18) for controlling the regulating means (15) and responsive to the intensity of the probing, reflected and/or stimulated radiation are also included.

Claims

1. Diagnostic apparatus comprising:

(a) a source (1) of probing electromagnetic radiation

(b) means (2) for transmitting the output from the probing radiation source (1) to biological tissue (3) to be examined

(c) means (4,

     41) for detecting probing radiation reflected from the tissue (3) and stimulated radiation resulting from excitation of the tissue (3) by the probing radiation

(d) processing means (5-9) responsive to the reflected and stimulated radiations to produce a signal for diagnosis of the condition of the tissue, and

(e) means (15,

     16) for regulating the intensity of the probing radiation including a feedback circuit (16, 17,

     18) for controlling the regulating means (15) and responsive to the intensity of the reflected and stimulated radiation.

2. Diagnostic apparatus as claimed in claim 1, wherein the regulating means comprises a polarising device (15) for varying the intensity of the radiation emitted by the probing radiation source (1), drive means (18) for adjusting the polarising device, and a sensor (17) arranged to be responsive to the reflected and stimulated radiations, said drive means (18) being responsive to the sensor so as to adjust the polarising device and vary the intensity of the probing radiation.

3. Diagnostic apparatus as claimed in claim 2, wherein the source of probing electromagnet radiation produces an output defining an optical axis, and including an optical divider (16) disposed on the optical axis for directing a fraction of the reflected and stimulated radiations to the sensor (17) which is located remotely from the optical axis.

4. Diagnostic apparatus as claimed in claim 1, wherein the probing radiation source is a laser source (1) and the means for regulating the intensity of the probing radiation comprises a partial mirror (16) disposed at the rear of the laser source, said partial mirror transmitting a fraction of the radiation from the source to a sensor (17) which is responsive to the radiation and actuates a regulating device (18) controlling the transparency of the mirror so as to adjust the radiation transmitted therethrough and therefore the intensity of the probing radiation emitted by the laser source.

5. Diagnostic apparatus as claimed in claim 1, wherein the feedback circuit (16,17,18) includes circuit means for effecting a fast, stepped, coarse adjustment of the regulating means and a precision tuning circuit means.

6. Diagnostic apparatus as claimed claim 1, wherein the feedback circuit (16,17,18) includes means for manually adjusting the regulating means (15,16).

7. Diagnostic apparatus as claimed in claim 1, wherein the processing means includes spectral attenuating means (5) for varying the absolute and relative intensities of the reflected and stimulated radiations.

8. Diagnostic apparatus as claimed in claim 1, wherein the processing means includes a monochromator (6) for processing the reflected and stimulated radiations.

9. Diagnostic apparatus as claimed in claim 8 including focusing means (35) located between the spectral attenuator (5) and the monochromator (6) for independently focusing the reflected and stimulated radiations on to a dispersive element (33) of the monochromator, said focusing means being adapted to regulate the diameter of the reflected and stimulated radiation beams at the surface of the dispersive element, and an optical ruler (34) on to which the beams are reflected by the dispersive element.

10. Diagnostic apparatus as claimed in claim 1 wherein the probing radiation source comprises a source (1) for producing optical radiation within the electromagnetic spectrum.

11. Diagnostic apparatus as claimed in claim 10, wherein the source for producing optical radiation comprises a laser source (1) of probing radiation and includes a laser (10a), a spectral element (11) for dividing the radiation emitted by the laser (10a) into a number of discrete spectral components within the bandwidth of the laser, a selection device (12) for selecting discrete spectral components of the radiation, whereby the wavelengths of the probing radiation are adjustable in order to obtain information from different depths in the biological tissue (3) being examined and to which the different wavelengths can penetrate, said selection device (12) also controlling the intensity and physical location of the discrete components, and a wavelength mixer (13) for combining the selected radiation components for launching into the transmitting means (2).

12. Diagnostic apparatus as claimed in claim 1 wherein the probing radiation source (1) produces a wave tunable in the band between 0.3-25 μ

m.

13. Diagnostic apparatus as claimed in claim 1, wherein at least one of the transmitting means (2) and the detecting means (4) comprise fibre optic means.

14. Diagnostic apparatus as claimed in claim 13, including means (21, 22, 36) for coupling the fibre optic means to the tissue (3) to be examined and for regulating the distance of the output and input ends thereof from the tissue.

15. Diagnostic apparatus as claimed in claim 1, including calibrating means (10) adapted to supply the detecting means (4) with radiation signals simulating reflected and stimulated radiation attainable from biological tissue having different healthy and pathological conditions to produce standardised signals, and means for transmitting the standardised signals to the processing means (7) for comparison with real time signals.

16. Diagnostic apparatus as claimed in claim 15, wherein the calibrating means (10) includes interchangeable plates, each of which has optical characteristics simulating tissue, and wherein the calibrating means is operable to cause the probing radiation emitted from the output of the transmitting means (2) to be incident on a selected plate of the calibration means such that the resulting reflected and stimulated radiation is sensed by the detecting means (4).

17. Diagnostic apparatus as claimed in claim 1, including means for determining the boundaries of pathological tissue and wherein the processing means is coupled to the means for determining the boundaries of pathological tissue.

18. Diagnostic apparatus as claimed in claim 1, wherein the processing means includes a visual display device (8) for displaying an image of the area of tissue under examination.

19. Diagnostic apparatus as claimed in claim 1, wherein the means (2) for probing signal transmission and means (4, 41) for probing tissue (3) signal detection detecting probing and stimulating radiation are incorporated in means (31) located at a given distance from the surface plane of biological tissue to obtain salient features of the anathomotopographical zone under survey.

20. Diagnostic apparatus as claimed in claim 1 wherein the means (2) for transmitting the output from the probing radiation source and the means (4, 41) for detecting probing and stimulating radiation are incorporated in means (31), comprising a space scanner producing visual images of discrete pathological spots and graphical diagrams of lesions showing increased or decreased activity of cells on the background of healthy bio-tissues.

21. Diagnostic apparatus as claimed in claim 1, incorporating external means (42) designed to regulate the intensity of the stimulated radiation on the tissue (3) under survey.

22. Diagnostic apparatus as claimed in claim 21 wherein external means (42) is a source emitting one of beta and gamma radiation onto the tissue under survey.

23. Diagnostic apparatus as claimed in claim 21 wherein external means (42) is a source, radiating in band 0.2 to 11 μ

m.

24. Diagnostic apparatus as claimed in claim 21 wherein external means (42) regulates at least one of the surface temperature and the temperature inside the volume of the tissue (3) under survey.

25. Diagnostic apparatus as claimed in claim 21 wherein external means (42) regulates stimulated radiation intensity on the basis of at least one of electrical, optical, magnetic, chemical and biological input.

26. Diagnostic apparatus as claimed in claim 21 wherein external means (42) regulates stimulated radiation intensity on the basis of injection of medicinal preparations.

27. Diagnostic apparatus as claimed in claim 1 including a photoplethysmograph means (45) for measuring microcirculation and oxygenation of the tissue and a therapeutic optical radiation dosimeter, and wherein the output of the photoplethysmograph operates to control the therapeutic optical radiation dosimeter.

28. Diagnostic apparatus as claimed in claim 1 incorporating means (46) presenting medical visualisation of at least one of interior and surface structures of a living organism.

29. Diagnostic apparatus as claimed in claim 28, incorporating means (46) for obtaining and superposing images selected from visual, Roentgen, ultrasonic, magnetic-resonance, thermographic, radio-nucleus and computer-tomographic diagnostic images on a single display (48) with the object of at least one of consecutive and joint tissue diagnostic survey.

30. Diagnostic apparatus as claimed in claim 1 wherein the means (2) for transmitting the output from the probing radioactive source (1) and the means (4, 41) for detecting probing and stimulating radiation are incorporated in means (49) used to perform biopsy tests and to produce signals in the mode of the interstitial tissue diagnostics.

31. Diagnostic apparatus as claimed in claim 1 in combination with apparatus for treating tissue including laser means (44) for treating the tissue under examination by the diagnostic apparatus.

32. Diagnostic apparatus as claimed in claim 1 in combination with apparatus for treating tissue incorporating means (44), comprising a radioactive source for performing radial therapy, means for measuring microcirculation and tissue oxygenation, means for tissue oxygenation stimulation with the object of overcoming resistance and controlling radiomodifying properties of hypoxic lesion cells.

33. Diagnostic apparatus as claimed in claim 32, wherein the means for tissue oxygenation stimulation comprises an optical source, radiating in band 0.4 to 11 μ

m.

34. Diagnostic apparatus as claimed in claim 32, wherein the means for tissue oxygenation stimulation comprises at least one of electrical and magnetic field source.

35. Diagnostic apparatus as claimed in claim 32, wherein the means for tissue oxygenation stimulation comprises at least one of a compression chamber for breathing and a local generator of oxygen and at least one of oxygen derivatives and oxygen containing mixture in the lesion area.

36. Diagnostic apparatus as claimed in claim 32, wherein the means for tissue oxygenation stimulation comprises medical injection of vasodilating preparations.

37. Diagnostic apparatus as claimed in claim 1 incorporating an elipticity-meter for defining at least one of roughness, turgor and humidity and biological objects on the noncontact basis.

38. A method of diagnosing the condition of biological tissue (3), comprising the steps of impinging electromagnetic radiation on the tissue, detecting probing radiation reflected from the tissue and stimulated radiation resulting from excitation of the tissue by the probing radiation, processing the reflected and stimulated radiations to produce a signal identifying the condition of the tissue, monitoring the intensity of the probing radiation by sensing a fraction of the reflected and stimulated radiations, and regulating the intensity of the probing radiation in response to the intensity of said fraction.

39. A method as claimed in claim 38 in combination with a method of treating tissue including the steps of treating the tissue under diagnosis and repeating the diagnosis and treatment until the tissue is diagnosed as normal.

40. A method as claimed in claim 39, including the steps of producing standardised signals corresponding to the intensities of the probing and stimulated radiations, measuring within a pathological area of the tissue, at least one of inflammatory, dystrophic and oncological activity by comparing reflection coefficients of reflected and stimulated radiations in real time with the standardised signals, and conducting treatment by periodically obtaining the reflection coefficients of the reflected and stimulated radiations and comparing their rate of change with database information.

41. A method of defining the state of biological tissue (3), using apparatus including a source of probing electromagnetic radiation, means for transmitting an output from the source of probing electromagnetic radiation to biological tissue to be examined, and means for detecting probing radiation reflected from the tissue and stimulated radiation resulting from excitation of the tissue by the probing radiation, and including the steps of:

(a) transmitting a probing signal comprising probing radiation from the source of probing electromagnetic radiation to biological tissue to be examined,

(b) detecting probing radiation reflected from the tissue and stimulated radiation resulting from excitation of the tissue by the probing radiation,

(c) modulating amplitude, frequency and temporal characteristics of the probing signal, and

(d) step-by-step analysis, and amplitude, frequency and temporal characteristics processing of the tissue reflected probing signal and the signal stimulated by the probing irradiation, and of variations invoked by modulation of the characteristics of the probing signal, to define the state of the biological tissue.

42. A method of defining the state of biological tissue (3), using apparatus including a source of probing electromagnetic radiation, means for transmitting an output from the source of probing electromagnetic radiation to biological tissue to be examined, and means for detecting probing radiation reflected from the tissue and stimulated radiation resulting from excitation of the tissue by the probing radiation, and including the steps of:

(a) transmitting a probing signal comprising probing radiation from the source of probing electromagnetic radiation to biological tissue to be examined,

(b) detecting probing radiation reflected from the tissue and stimulated radiation resulting from excitation of the tissue by the probing radiation,

(c) modulating amplitude, frequency and temporal characteristics of external means, regulating intensity of the stimulated radiation, and

(d) step-by-step analysis, and amplitude, frequency and temporal characteristics processing of the tissue reflected probing signal and the signal stimulated by the probing irradiation, and of variations invoked by modulation of the characteristics of the external means, to define the state of the biological tissue.

43. A method of defining the state of biological tissue (3), using apparatus including a source of probing electromagnetic radiation, means for transmitting an output from the source of probing electromagnetic radiation to biological tissue to be examined, and means for detecting probing radiation reflected from the tissue and stimulated radiation resulting from excitation of the tissue by the probing radiation, and including the steps of:

(a) transmitting a probing signal comprising probing radiation from the source of probing electromagnetic radiation to biological tissue to be examined and the probing signal further comprising a fixed band wave scanning in accordance with at least one of definite and random control,

(b) detecting probing radiation reflected from the tissue and stimulated radiation resulting form excitation of the tissue by the probing radiation, and

(c) step-by-step dynamic analysis of the stimulated signal characteristic frequencies and amplitude peak-value displacements due to the probing signal fixed band wave scanning to define the state of the biological tissue.

44. A method of defining the state of biological tissue (3) and radiant therapy for treating the tissue, using apparatus including a source of probing electromagnetic radiation, means for transmitting an output from the source of probing electromagnetic radiation to biological tissue to be examined, means for detecting probing radiation reflected from the tissue and stimulated radiation resulting from excitation of the tissue by the probing radiation, a radioactive source for performing radiant therapy, and means for tissue oxygenation stimulation, and the process of defining the state of biological tissue including the steps of:

(a) transmitting a probing signal comprising probing radiation from the source of probing electromagnetic radiation to biological tissue to be examined,

(b) detecting probing radiation reflected from the tissue and stimulated radiation resulting from excitation of the tissue by the probing radiation, the process of radiant therapy including the steps of;

(c) performing oxygenation stimulation to reach maximal oxygen concentration in tissue with subsequent radiant therapy and

(d) repeating steps a) through c) until the tissue is diagnosed as normal.