SINGLE-USE INTERNAL DOSIMETERS FOR DETECTING RADIATION IN MEDICAL PROCEDURES/THERAPIES
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.
1 . 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.
2 . An internal radiation dosimeter according to claim 1 , wherein the calibration data comprises a zero temperature coefficient.
3 . An internal radiation dosimeter according to claim 1 , wherein the electronic memory comprises electronic instructions for automatically controlling how a remote reader communicates with the dosimeter.
4 . An internal dosimeter according to claim 1 , wherein the electronic memory is configured to store patient specific data and radiation exposure data.
5 . An internal dosimeter according to claim 1 , wherein the radiation dosimeter is configured to inhibit re-use of the dosimeter.
6 . An internal dosimeter according to claim 1 , 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.
7 . An internal dosimeter according to claim 1 , 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.
8 . An internal dosimeter according to claim 1 , 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.
9 . An internal dosimeter according to claim 7 , 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.
10 . An internal dosimeter according to claim 9 , wherein the elongate flex circuit is held inside a flexible elastomeric elongate probe body.
11 . An internal dosimeter according to claim 1 , 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.
12 . An internal dosimeter according to claim 11 , wherein the dosimeter is configured to provide data from each radiation sensor circuit for determining maxima, minima and average exposure.
13 . An internal dosimeter according to claim 1 , 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.
14 . An internal dosimeter according to claim 1 , 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.
15 . An internal dosimeter according to claim 1 , wherein the dosimeter is integrated in and/or on a mouthpiece.
16 . An internal dosimeter according to claim 15 , 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.
17 . An internal dosimeter according to claim 16 , 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.
18 . An internal dosimeter according to claim 17 , 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.
19 . An internal dosimeter according to claim 1 , wherein the internal dosimeter has a body that is configured as a generally conformable nose cavity plug.
20 . An internal dosimeter according to claim 19 , 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.
21 . An internal dosimeter according to claim 1 , wherein the internal dosimeter has a body that is configured as a generally conformable ear plug.
22 . An internal dosimeter according to claim 21 , 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.
23 . An internal dosimeter according to claim 22 , wherein the dosimeter is held in and/or on a flexible male genourinary catheter.
24 . An internal dosimeter according to claim 23 , 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.
25 . An internal dosimeter according to claim 24 , 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.
26 . An internal dosimeter according to claim 25 , 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.
27 . An internal dosimeter according to claim 26 , wherein the flex circuit comprises a plurality of axially spaced apart radiation sensor circuits that include electrical traces that terminate at the tab portion.
28 . An internal dosimeter according to claim 27 , wherein the dosimeter is configured to obtain radiation data during brachytherapy and/or external radiation beam therapy.
29 . An internal dosimeter according to claim 1 , wherein the dosimeter has a body that is configured as a flexible female genourinary probe.
30 . An internal dosimeter according to claim 29 , wherein the probe is sized and configured as a vaginal probe.
31 . An internal dosimeter according to claim 29 , wherein the probe is sized and configured as a urethral probe.
32 . An internal dosimeter according to claim 29 , 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.
33 . An internal dosimeter according to claim 1 , wherein the dosimeter has a body that is configured as a rectal probe.
34 . An internal dosimeter according to claim 33 , 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.
35 . An internal dosimeter according to claim 1 , wherein the dosimeter is biocompatible and sterilized and held in a sealed package for medical use.
36 . An internal dosimeter according to claim 1 , 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.
37 . An internal dosimeter according to claim 1 , wherein the radiation sensor circuit includes a MOSFET that is devoid of floating gate structures and is unbiased during radiation.