Disposable single-use internal dosimeters for detecting radiation in medical procedures/therapies

• US 20050010110A1
• Filed: 06/10/2004
• Published: 01/13/2005
• Est. Priority Date: 11/30/2001
• Status: Active Grant

• Current Assignee: SNC Holdings Corp.
• Original Assignee: Sicel Technologies, Inc.
• Inventors: Widener, Steven R., Mann, Gregory Glenwood, Lehman, Phillip M., Black, Robert D., Carroll, John
• Granted Patent: US 7,491,942 B2
• Time in Patent Office: Days
• US Class Current: 600/436
• CPC Class Codes: A61N 2005/1072 taking into account movement of the target
• CPC Class Codes: A61N 5/1048 Monitoring, verifying, controlling systems and methods
• CPC Class Codes: A61N 5/1071 for verifying the dose delivered by the treatment plan
• CPC Class Codes: G01T 1/026 Semiconductor dose-rate meters

Abstract

Methods, systems, devices, and computer program products include positioning single-use radiation internal dosimeters with MOSFETs into a patient to evaluate the radiation dose delivered during a medical procedure or treatment session. The MOSFETs can be unpowered during irradiation.

Claims

1. A method for monitoring radiation exposure for a patient undergoing a medical procedure, comprising:

inserting a single-use dosimeter into a patient, wherein the at least one dosimeter comprises at least one radiation sensor circuit with a MOSFET and electronic memory that holds calibration data for the MOSFET;

exposing the patient to radiation in a medical procedure during a treatment session;

transmitting data from the dosimeter to a dose-reader device after the exposing step, the transmitting data comprising the calibration data and data associated with a change in an operational parameter in the MOSFET of the dosimeter radiation sensor circuit;

removing the dosimeter from the patient during or proximate in time to an end of the treatment session; and

determining radiation received by the patient during the exposing step based on the change in the operational parameter of the MOSFET and the calibration data.

2. A method according to claim 1, wherein the at least one radiation sensor circuit includes a single operative MOSFET that is unbiased and unpowered during irradiation.

3. A method according to claim 1, wherein the transmitting data is carried out by inserting a tab extending from the at least one dosimeter into a port in the dose-reader device.

4. A method according to claim 1, further comprising storing radiation-data relating to the exposing and/or determining step on a memory device integrated with the at least one dosimeter.

5. A method according to claim 1, further comprising storing a plurality of patient specific data records on the reader, then transmitting the radiation data obtained by the reader from the at least one dosimeter to a remote computer.

6. A method according to claim 1, further comprising sterilizing the single-use dosimeter and packaging the single-use dosimeter in a sterile package suitable for human medical use.

7. A method according to claim 1, wherein the at least one dosimeter is held in and/or on a mouthpiece, and wherein the inserting step comprises placing the mouthpiece in the mouth of the patient.

8. A method according to claim 7, wherein the mouthpiece is a bite block that includes an outwardly extending tab portion, and wherein the transmitting data step comprises engaging a portable reader with the tab portion to electronically engage the reader with the radiation sensor circuit and the electronic memory.

9. A method according to claim 1, wherein the at least one dosimeter is held in a generally conformable nose cavity plug, and wherein the inserting step comprises inserting the plug into a nasal cavity.

10. A method according to claim 9, wherein the nose cavity plug includes an outwardly extending tab portion, and wherein the transmitting data step comprises engaging a portable reader with the tab portion to electronically engage the reader with the radiation sensor circuit and the electronic memory.

11. A method according to claim 1, wherein the at least one dosimeter is held in a generally conformable ear plug, and wherein the inserting step comprises inserting the plug into an ear canal or cavity of the patient.

12. A method according to claim 11, wherein the ear plug includes an outwardly extending tab portion, and wherein the transmitting data step comprises engaging a portable reader with the tab portion to electronically engage the reader with the radiation sensor circuit and the electronic memory.

13. A method according to claim 12, wherein the at least one dosimeter is configured such that at least one dosimeter is held by two different ear plugs, and wherein the step of inserting comprises inserting the plugs into both a right and a left ear canal of the patient.

14. A method according to claim 1, wherein the at least one dosimeter is held in and/or on a flexible male genourinary catheter.

15. A method according to claim 14, wherein the dosimeter comprises a flex circuit with a MOSFET held at a distal end portion of the catheter and an external outwardly extending tab portion located at a proximal end portion of the catheter, and wherein the transmitting data step comprises engaging a portable reader with the tab portion to electronically engage the reader with the radiation sensor circuit and the electronic memory.

16. A method according to claim 14, wherein the inserting step is carried out so that the MOSFET in at least one of the at least one radiation sensor circuit is disposed proximate a prostate of a male patient.

17. A method according to claim 16, wherein the exposing step is carried out during brachytherapy or external radiation beam therapy.

18. A method according to claim 1, wherein the at least one dosimeter is held in and/or on a flexible female genourinary probe.

19. A method according to claim 18, wherein the at least one dosimeter is held in a vaginal probe.

20. A method according to claim 18, wherein the at least one dosimeter is held in a urethral probe.

21. A method according to claim 18, wherein the at least one dosimeter includes an outwardly extending tab portion, and wherein the transmitting data step comprises engaging a portable reader with the tab portion to electronically engage the reader with the radiation sensor circuit and the electronic memory.

22. A method according to claim 1, wherein the at least one dosimeter is held in or on a rectal probe.

23. A method according to claim 22, wherein the rectal probe includes an outwardly extending tab portion, and wherein the transmitting data step comprises engaging a portable reader with the tab portion to electronically engage the reader with the radiation sensor circuit and the electronic memory.

24. A method according to claim 1, wherein the exposing step is carried out during a high-dose rate brachytherapy using a plurality of open catheters held in a transcutaneous geometric matrix with a radioactive Ir-192 source that travels in the open catheters into the patient, and wherein the inserting step comprises placing the dosimeter inside at least one of the open catheters.

25. A method according to claim 24, wherein the dosimeter includes an outwardly extending tab portion, and wherein the transmitting data step comprises engaging a portable reader with the tab portion to electronically engage the reader with the radiation sensor circuit and the electronic memory.

26. A method according to claim 25, wherein the at least one dosimeter is a plurality of axially aligned dosimeters, each having a respective radiation sensor circuit with a single operative MOSFET, and wherein the determining step comprises determining a radiation dose for each of the radiation sensor circuits to provide a plurality of dose readings associated with exposure to the Ir-192.

27. A method according to claim 1, further comprising positioning at least one surface mount dosimeter patch on the patient, the at least one surface mount dosimeter patch comprising a flex circuit with a radiation sensor circuit having an unbiased MOSFET and electronic memory configured to hold calibration data for the radiation sensor circuit.

28. A method according to claim 27, further comprising transmitting data from the at least one surface mount patch to the dose-reader device after the exposing step to obtain the calibration data and data associated with a change in an operational parameter in the MOSFET of the dosimeter radiation sensor circuit to determine radiation received by the patient during the exposing step based on the change in the operational parameter of the MOSFET and the calibration data.

29. A system for monitoring radiation administered to a patient during a diagnostic and/or therapeutic treatment, the system comprising:

at least one single-use internal dosimeter, the internal dosimeter comprising at least one radiation sensor circuit comprising a MOSFET having an associated threshold voltage that changes when exposed to radiation and electronic memory comprising calibration data for determining radiation dose; and

a portable dose-reader configured to obtain voltage threshold data and calibration data from the at least one internal dosimeter corresponding to a dose amount of radiation exposure received during irradiation exposure.

30. A system according to claim 29, wherein the at least one internal dosimeter comprises at least one contact region that is configured and sized to enter a port in the dose-reader to transmit the voltage threshold data and the calibration data.

31. A system according to claim 29, wherein the dose reader is sized and configured as a handheld and/or pocket-sized portable reader.

32. A system according to claim 29, wherein the dose-reader is configured to obtain data from the internal dosimeter and from a surface mount dosimeter patch and determine radiation dose at a monitored location from each type of dosimeter.

33. A system according to claim 29, wherein the internal dosimeter is sized and configured as a natural body lumen and/or cavity probe.

34. A system according to claim 29, wherein the internal dosimeter is sized and configured as a transcutaneous probe.

35. A system according to claim 33, wherein the internal dosimeter is integrated in and/or on a mouthpiece.

36. A system according to claim 35, wherein the reader further comprises computer program code for identifying what type of dosimeter is undergoing evaluation from a plurality of differently configured dosimeters configured to be evaluated by the dose reader.

37. A system according to claim 36, wherein the reader comprises computer program code that prompts a user to identify the dosimeter configuration being evaluated.

38. A system according to claim 36, wherein the reader automatically identifies the type of dosimeter based on data in the electronic memory of the dosimeter.

39. A system according to claim 35, wherein the mouthpiece is a bite block that includes an externally extending tab portion, and wherein the tab portion is configured to electronically engage the reader with the radiation sensor circuit and the electronic memory.

40. A system according to claim 33, wherein the internal dosimeter is configured as a generally conformable nose cavity plug.

41. A system according to claim 40, wherein the nose cavity plug includes a tab portion that is configured to engage the portable reader to electronically engage the reader with the radiation sensor circuit and the electronic memory.

42. A system according to claim 33, wherein the internal dosimeter is configured as a generally conformable ear plug.

43. A system according to claim 42, wherein the ear plug includes an outwardly extending tab portion that is configured to electronically engage the portable reader with the radiation sensor circuit and the electronic memory.

44. A system according to claim 33, wherein the at least one dosimeter is held in and/or on a flexible male genourinary catheter.

45. A system according to claim 44, wherein the dosimeter comprises a flex circuit with a MOSFET held at a distal end portion of the catheter and a tab portion located at a proximal end portion of the catheter that is configured to electronically engage the portable reader with the radiation sensor circuit and the electronic memory.

46. A system according to claim 45, wherein the catheter comprises an expandable balloon that expands above a male urinary sphincter and holds the catheter in position during irradiation so that the MOSFET in at least one of the at least one radiation sensor circuits is configured to reside proximate a prostate of a male patient above the urinary sphincter.

47. A system according to claim 46, wherein the flex circuit is configured to be slidably received in the catheter to allow in situ axially adjustable placement of at least one of the radiation sensor circuits.

48. A system according to claim 46, wherein the dosimeter is configured to obtain radiation data during brachytherapy and/or external radiation beam therapy.

49. A system according to claim 33, wherein the at least one dosimeter is held in and/or on a flexible female genourinary probe.

50. A system according to claim 49, wherein the probe is configured as a vaginal probe.

51. A system according to claim 49, wherein the probe is configured as a urethral probe.

52. A system according to claim 49, wherein the dosimeter includes a tab portion configured to engage the portable reader to electronically engage the reader with the radiation sensor circuit and the electronic memory.

53. A system according to claim 33, wherein the dosimeter configured as a rectal probe.

54. A system according to claim 53, wherein the rectal probe includes an outwardly extending tab portion configured to electronically engage a portable reader with the radiation sensor circuit and the electronic memory.

55. A system according to claim 34, wherein the at least one dosimeter is sized and configured to be received in at least one of a plurality of open catheters held in a transcutaneous geometric matrix during HDR (high dose rate) brachytherapy to provide radiation dose estimates of a radioactive source that travels in the open catheters into the patient.

56. A system according to claim 55, wherein the dosimeter includes an outwardly extending tab portion configured to engage a portable reader to electronically engage the reader with the radiation sensor circuit and the electronic memory.

57. A system according to claim 29, wherein the at least one dosimeter is a plurality of axially aligned dosimeters held on a common flex circuit in a common probe body, each having a respective radiation sensor circuit with a single operative MOSFET configured to provide radiation data for a plurality of axially spaced apart subsurface depth locations.

58. A system according to claim 29, wherein the calibration data comprises data associated with a zero temperature coefficient of the MOSFET for radiation quantification.

59. A system according to claim 29, wherein the electronic memory is configured to store radiation data and patient information.

60. A system according to claim 29, wherein the at least one dosimeter is biocompatible and sterilized and held in a package for medical use.

61. A system according to claim 29, wherein the reader comprises computer program code for prompting a clinician to enter calibration data associated with a particular patient and medical procedure and computer program code for determining radiation exposure received by the patient.

62. A system according to claim 61, wherein the reader comprises computer program code for prompting a user to select the type of radiation dosimeter being evaluated from a predetermined list of dosimeter types including external and internal dosimeter configurations.

97. An internal dosimeter according to claim 33, wherein the dosimeter is sized and configured to be slidably received in at least one of a plurality of open catheters held in a transcutaneous geometric matrix during HDR (high dose rate) brachytherapy to provide radiation dose estimates of a radioactive source that travels in the open catheters into the patient.

98. An internal dosimeter according to claim 97, wherein the dosimeter includes an outwardly extending tab portion that defines the reader contact zone and is configured to enter a port in the portable reader to electronically engage the reader with the radiation sensor circuit and the electronic memory.

99. An internal dosimeter according to claim 98, wherein the dosimeter comprises a plurality of axially spaced apart radiation sensor circuits held on a common flex circuit, each having a respective single operative MOSFET configured to provide dose data at a plurality of internal depth locations.

63. An internal single-use radiation dosimeter, the dosimeter comprising:

at least one radiation sensor circuit with a MOSFET having an associated threshold voltage that changes when exposed to radiation to provide quantifiable radiation exposure data, wherein the radiation sensor circuit is unpowered during irradiation;

electronic memory having radiation calibration data for the MOSFET; and

a reader contact zone on the dosimeter configured to allow a portable reader to electrically engage the dosimeter to obtain the radiation exposure and calibration data, wherein the radiation dosimeter is a single-use dosimeter configured for use during a single medical treatment session.

64. An internal radiation dosimeter according to claim 63, wherein the calibration data comprises a zero temperature coefficient.

65. An internal radiation dosimeter according to claim 63, wherein the electronic memory comprises electronic instructions for automatically controlling how a remote reader communicates with the dosimeter.

66. An internal dosimeter according to claim 63, wherein the electronic memory is configured to store patient specific data and radiation exposure data.

67. An internal dosimeter according to claim 63, wherein the radiation dosimeter is configured to inhibit re-use of the dosimeter.

68. An internal dosimeter according to claim 63, wherein, in operation, the dosimeter electronic memory is configured to allow a portable reader to write patient specific data and radiation exposure calculation values to the electronic memory once.

69. An internal dosimeter according to claim 63, wherein the dosimeter is sized and configured to reside in a natural body lumen with the MOSFET of the radiation sensor circuit held a distance in the natural body lumen and the reader contact zone held external of the body.

70. An internal dosimeter according to claim 63, wherein the dosimeter is sized and configured as a transcutaneous or subcutaneous dosimeter probe with the MOSFET of the radiation sensor circuit held at a subsurface depth in tissue in the body and with the reader contact zone residing external of the body.

71. An internal dosimeter according to claim 69, wherein the dosimeter comprises an elongate flex circuit with the radiation circuit MOSFET held on a distal end portion thereof and the reader contact zone held on an opposing proximal portion, and with at least one electrical trace extending therebetween.

72. An internal dosimeter according to claim 71, wherein the elongate flex circuit is held inside a flexible elastomeric elongate probe body.

73. An internal dosimeter according to claim 63, wherein the dosimeter comprises an elongate flex circuit with a plurality of axially spaced apart radiation sensor circuits, each radiation sensor circuit comprising a single operative MOSFET, and wherein the radiation sensor circuits comprise separate electrical traces that extend from a respective MOSFET to terminate at the reader contact zone.

74. An internal dosimeter according to claim 73, wherein the dosimeter is configured to provide data from each radiation sensor circuit for determining maxima, minima and average exposure.

75. An internal dosimeter according to claim 63, wherein the internal dosimeter contact zone is configured and sized to enter a port in the portable dose-reader to transmit the voltage threshold data and the calibration data.

76. An internal dosimeter according to claim 63, wherein the internal dosimeter is configured and sized to reside in a natural mouth cavity with the MOSFET of the radiation sensor circuit held a distance in the natural body lumen and the reader contact zone held external of the body.

77. An internal dosimeter according to claim 63, wherein the dosimeter is integrated in and/or on a mouthpiece.

78. An internal dosimeter according to claim 77, wherein the mouthpiece is a bite block that includes at least one externally extending tab portion that defines the reader contact zone, and wherein at least one tab portion is configured to enter into a port in the reader to electronically engage the reader with the radiation sensor circuit and the electronic memory.

79. An internal dosimeter according to claim 78, wherein the mouthpiece is configured to hold a plurality of spaced apart radiation sensor circuits, each with a respective MOSFET, each having a separate outwardly extending tab for allowing contact with the portable reader.

80. An internal dosimeter according to claim 79, wherein the tab portions comprise a removeable cover that remains in position when the bite block is in a mouth cavity during irradiation, and is removeable for electronic access thereto after irradiation.

81. An internal dosimeter according to claim 63, wherein the internal dosimeter has a body that is configured as a generally conformable nose cavity plug.

82. An internal dosimeter according to claim 81, wherein the nose cavity plug includes a tab portion that defines the reader contact zone and is configured to enter a port in the reader to electronically engage the reader with the radiation sensor circuit and the electronic memory.

83. An internal dosimeter according to claim 63, wherein the internal dosimeter has a body that is configured as a generally conformable ear plug.

84. An internal dosimeter according to claim 83, wherein the ear plug includes an outwardly extending tab portion that defines the reader contact zone and is configured to enter a port in the portable reader to electronically engage the reader with the radiation sensor circuit and the electronic memory.

85. An internal dosimeter according to claim 84, wherein the dosimeter is held in and/or on a flexible male genourinary catheter.

86. An internal dosimeter according to claim 85, wherein the dosimeter comprises a flex circuit with a MOSFET held at a distal end portion of the catheter and a tab portion located at a proximal end portion of the catheter that defines the reader contact zone and is configured to enter a port in the portable reader to electronically engage the reader with the radiation sensor circuit and the electronic memory.

87. An internal dosimeter according to claim 86, wherein the catheter comprises an expandable balloon that is expanded during irradiation to position the MOSFET in at least one of the at least one radiation sensor circuits proximate a prostate of a male patient above the urinary sphincter.

88. An internal dosimeter according to claim 87, wherein the flex circuit is configured to be slidably received in the catheter to allow in situ axially adjustable placement of at least one of the radiation sensor circuits.

89. An internal dosimeter according to claim 88, wherein the flex circuit comprises a plurality of axially spaced apart radiation sensor circuits that include electrical traces that terminate at the tab portion.

90. An internal dosimeter according to claim 89, wherein the dosimeter is configured to obtain radiation data during brachytherapy and/or external radiation beam therapy.

91. An internal dosimeter according to claim 63, wherein the dosimeter has a body that is configured as a flexible female genourinary probe.

92. An internal dosimeter according to claim 91, wherein the probe is sized and configured as a vaginal probe.

93. An internal dosimeter according to claim 91, wherein the probe is sized and configured as a urethral probe.

94. An internal dosimeter according to claim 91, wherein the dosimeter includes a tab portion that defines the reader contact zone and is configured to enter a port in the portable reader to electronically engage the reader with the radiation sensor circuit and the electronic memory.

95. An internal dosimeter according to claim 63, wherein the dosimeter has a body that is configured as a rectal probe.

96. An internal dosimeter according to claim 95, wherein the rectal probe includes an outwardly extending tab portion that defines the reader contact zone and is configured to enter a port in the portable reader to electronically engage the reader with the radiation sensor circuit and the electronic memory.

100. An internal dosimeter according to claim 63, wherein the dosimeter is biocompatible and sterilized and held in a sealed package for medical use.

101. An internal dosimeter according to claim 63, wherein the at least one radiation circuit is configured to detect radiation doses in the range of at least one of:

from about 20 to about 1500 cGy, from about 20-500 cGy, and from about 500-1500 cGy.

102. An internal dosimeter according to claim 63, wherein the radiation sensor circuit includes a MOSFET that is devoid of floating gate structures and is unbiased during radiation.

103. A portable medical radiation dose reader, comprising:

a portable housing; and

a circuit held in the portable housing, the circuit configured to communicate with an electronic memory of at least one single use internal dosimeter to obtain voltage threshold data corresponding to a dose amount of radiation exposure that the at least one dosimeter is exposed to during irradiation and to prompt a user to input predetermined data associated with dose evaluation, patient data and/or clinic data.

104. The reader of claim 103, wherein the reader is also configured to communicate with an electronic memory of at least one single use external skin mount radiation dosimeter patch to obtain voltage threshold data corresponding to a dose amount of radiation exposure that the at least one patch is exposed to during irradiation and to prompt a user to input predetermined data associated with dose evaluation, patient data and/or clinic data

105. The reader of claim 104, wherein the reader comprises a port that is configured to receive an input portion of the internal and surface mount dosimeter to make electrical contact therewith to communicate with the electronic memory to obtain the threshold data corresponding to the dose amount of radiation exposure the at least one internal and/or surface mount patch dosimeter is exposed to during the administering of therapeutic radiation.

106. The reader of claim 104, wherein the reader further comprises computer program code for identifying what type of dosimeter is undergoing evaluation, and computer program code that provides a selectable list of differently configured dosimeters, including an external skin mount patch and a plurality of different internal dosimeters, all configured to be evaluated by the dose reader.

107. The reader of claim 104, wherein the reader comprises computer program code that prompts a user to identify the dosimeter configuration being evaluated.

108. The reader of claim 104, wherein the reader comprises computer program code that automatically identifies the type of dosimeter being evaluated based on data in the electronic memory of the dosimeter.

109. The reader of claim 103, wherein the reader comprises computer program code for prompting a clinician to enter data associated with a particular patient and/or medical procedure and computer program code for determining radiation exposure received by the patient.