WO1996024859A1 - Messverfahren und sensor zur on-line in-vivo bestimmung der gewebeäquivalenten dosis bei der strahlentherapie - Google Patents
Messverfahren und sensor zur on-line in-vivo bestimmung der gewebeäquivalenten dosis bei der strahlentherapie Download PDFInfo
- Publication number
- WO1996024859A1 WO1996024859A1 PCT/DE1996/000174 DE9600174W WO9624859A1 WO 1996024859 A1 WO1996024859 A1 WO 1996024859A1 DE 9600174 W DE9600174 W DE 9600174W WO 9624859 A1 WO9624859 A1 WO 9624859A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- sensors
- tissue
- dose
- radiation
- sensor
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05G—X-RAY TECHNIQUE
- H05G1/00—X-ray apparatus involving X-ray tubes; Circuits therefor
- H05G1/08—Electrical details
- H05G1/26—Measuring, controlling or protecting
- H05G1/30—Controlling
- H05G1/38—Exposure time
- H05G1/42—Exposure time using arrangements for switching when a predetermined dose of radiation has been applied, e.g. in which the switching instant is determined by measuring the electrical energy supplied to the tube
- H05G1/44—Exposure time using arrangements for switching when a predetermined dose of radiation has been applied, e.g. in which the switching instant is determined by measuring the electrical energy supplied to the tube in which the switching instant is determined by measuring the amount of radiation directly
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N5/00—Radiation therapy
- A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
- A61N5/1048—Monitoring, verifying, controlling systems and methods
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
- G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
- G01T1/02—Dosimeters
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
- G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
- G01T1/16—Measuring radiation intensity
- G01T1/161—Applications in the field of nuclear medicine, e.g. in vivo counting
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05G—X-RAY TECHNIQUE
- H05G1/00—X-ray apparatus involving X-ray tubes; Circuits therefor
- H05G1/08—Electrical details
- H05G1/26—Measuring, controlling or protecting
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
- A61B6/58—Testing, adjusting or calibrating apparatus or devices for radiation diagnosis
- A61B6/582—Calibration
- A61B6/583—Calibration using calibration phantoms
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/02042—Multicore optical fibres
Definitions
- the invention relates to a method for in vivo and on-line determination of the tissue-equivalent dose in radiation therapy and to an apparatus for performing the method.
- thermoluminescent dosimeters It is known to perform an approximately tissue equivalent in vivo measurement of a dose using miniaturized thermoluminescent dosemeters in some applications.
- the limitation to certain applications is disadvantageous.
- the measurement result is only available after an extensive evaluation of the thermoluminescent dosimeter at the earliest one hour after the end of the irradiation.
- sensors are used whose material either have an effective atomic number that differs significantly from the tissue or have a low sensitivity to detection.
- a disadvantage is that an accurate measurement, especially at a photon radiation, is not possible, as the material of the sensor always v deviates on the tissue, and the absorbed dose is material dependent. In principle, no statement about the tissue depth is possible. Furthermore, it is disadvantageous to be limited in the choice of materials
- the object is achieved by a method having the features of claim 1
- the method according to claim 1 can be carried out as follows. First, the radiation dose is measured at one location by at least two sensors. The sensors are to be selected such that the radiation dose changes proportionally to the measurement signal within the measurement range. A proportionality between the measurement signal and the radiation dose achieved by a compensation calculation is sufficient
- At least two measurement signals Sj and S; of the sensors ⁇ and i used must show a different energy dependency of the sensitivity to rewetting for ionizing radiation. Such a different dependency is given for optical sensors with different effective atomic numbers Z e f.
- the different display can also be caused by different shielding of the sensors
- a signal Sj or Sj can have been determined by means of one sensor i or j or, for example, as an average of several measurement signals from several sensors used, which show the same dependence on the detection sensitivity for ionizing radiation. It is crucial that a value that is independent of the dose is used in the further evaluation.
- quotients such as (Sj - S;) / (Sj + Sj) or their reciprocal values can therefore be continued.
- the effective tissue depths d g to 5 belonging to the calculated quotients Qjj are to be determined. This is done using calibration tables or calibration curves. The data required for
- the material of the sensor does not have to be matched to the tissue and can therefore be chosen freely.
- the dose equivalent to tissue is determined very precisely.
- the effective tissue depth provides a measure of the depth in the tissue at which the measurement was made.
- the method according to the jerk-related method claim represents an advantageous embodiment. If a signal S] or S2 is measured twice by two identical sensors, instead of a single value, a corresponding averaging from these two signals can be used for the further calculation
- a measuring device for determining a tissue-equivalent radiation dose according to the method has at least two sensors which show a different energy dependence of the detection sensitivity for ionizing radiation.
- a sensor is to be understood as any component that changes one of its physical, chemical or technical properties when irradiated and this change is suitable as a measure of the radiation dose caused by the radiation.
- the change is suitable if the radiation dose is accompanied by a continuous change in the physical, chemical or technical properties.
- micro or fiber optic sensors e.g. B. known from DE 3929294 AI or DE 32 34 900 AI.
- a micro-optical sensor is a sensor with a diameter smaller than 1 mm.
- DE 3929294 A1 An example of such a change is the change in an optical property, such as induced damping, scintillation or fluorescence, known from DE 3929294 A1.
- DE 3929294 AI sensors are connected to measurement and evaluation electronics via fiber-optic, radiation-resistant transmission lines or fibers. The measurement signals are displayed by the electronics. If the sensors consist of micromechanical components, each individual sensor can be arranged in one lumen of a multi-lumen catheter.
- Two sensors show a different energy dependence of the detection sensitivity for ionizing radiation if the measurement signals differ to change. This change can be caused by the design, for example by a different effective atomic number in optical sensors or due to different shielding of the sensors.
- the measuring device is constructed rotationally symmetrically with respect to its sensors and consists of at least three sensors, at least two of which show the same energy dependence of the detection sensitivity for ionizing radiation
- the sensors are identical in construction, e.g. optical sensors with the same effective atomic number, the sensors show the same energy dependency of the sensitivity to detection. along which the sensors z. B. be inserted into a tissue Due to the rotationally symmetrical structure, the device is insensitive to rotation about this central axis
- Fig. 1 planar carrier element for coupling several fiber-optic radiation-sensitive sensors
- Fig. 2 Metal capillary as a carrier element for coupling fiber-optic radiation-sensitive sensors
- Fig. 3 Structure with a scintillating and a fiber-optic sensor measuring radiation-induced vaporization.
- Fig. 4 Three radiation-sensitive sensors in a multi-lumen catheter
- Fig. 6 effective tissue depth depending on the ratio of the signals of two sensors with different effective atomic number
- Fig. 7 Dependence of the calibration factors of two sensors with different effective atomic numbers on the effective tissue depth
- Fig. 8 dose measurements as a function of tissue depth
- FIG. 1 shows a rotationally symmetrical structure with three radiation-sensitive sensor fibers 1, 2 and 3.
- the middle sensor fiber 2 consists of a PbO fiber with 60% by weight lead oxide. This is coupled to a radiation-insensitive twin fiber 4, consisting of two quartz fibers (hard clad fibers with a high numerical aperture) in a common sheath 5.
- the sensor fibers 1 and 3 are Ge-P doped gradient index fibers (germanium approximately 26% by weight, phosphorus approximately 4% by weight), which are commercially available, radiation-hard Message fibers 6 and 7 (eg AT&T wheel Hard 3A) are spliced on.
- the sensor fibers 1, 2 and 3 are embedded in the planar substrate 8 in a rotationally symmetrical manner with respect to the longitudinal axis of the middle fiber 2.
- the substrate 8 consists of metal, glass or silicon. Overall, the planar structure is approximately 0.9 mm wide
- the twin fiber is used as a transmission fiber in order to avoid disturbing Fresnel reflections when reading out the radiation-induced light monitoring.
- the rotationally symmetrical arrangement of the sensors causes the measuring device to be insensitive to rotation about the longitudinal axis of the middle sensor 2 in the radiation field.
- the use of two germanium-phosphor sensors also improves the signal-to-noise ratio of the measurement signal when reading out the germanium-phosphor sensors 1 and 3
- the sensor fibers 1, 2 and 3 are irradiated, the light attenuation in the sensor fibers increases with increasing dose. The attenuation is therefore a measure of the radiation dose.
- the dependency between damping and dose in the PbO fiber differs from the dependency in the Ge-P-doped fibers 1 and 3 due to different effective atomic numbers
- the ends of the sensors are mirrored, opposite the ends to which the
- Transmission fibers 4, 6 and 7 are coupled.
- the mirroring is used for light reflection. Starting from the measuring and evaluation electronics, light reaches the sensors via the transmission fibers 4, 6 and 7. The light is reflected at the mirrored ends and is thus directed back to the electronics. The direction of travel of the light is illustrated in FIG. 1 by the six parallel arrows (in front of the transmission line).
- the electronics register the change in the attenuation and display this change as a measure of the dose
- Fig. 2 shows in principle the structure from Fig. 1. The only difference is the embedding in the VA capillary 9 instead of the planar substrate from Fig. 1. The twin fiber is fixed by means of epoxy adhesive 10
- the structure shown in cross section in FIG. 3 consists of a scintillating NaI crystal 11 as the first sensor and a PbO fiber 12 as the second sensor.
- the NaI crystal 11 also serves as a carrier element for the PbO fiber, which is also from the VA -Capillary 13 is encased.
- To increase the light output of the scintillating element its end faces are mirrored and its inner and outer surface 14 with a light-scattering material of low absorption, for. B. barium sulfate or titanium dioxide coated.
- the decoupling of light from the scintillating sensor 11 takes place through one or more windows 15, in front of which Optical fibers are fixed.
- the PbO sensor is in turn connected by means of a twin fiber.
- FIGS. 1 and 2 show a structure analogous to FIGS. 1 and 2. This time, however, a three-lumen catheter tube 16, shown in cross section, is used to position the sensors 1, 2 and 3.
- the PbO fiber 2 is covered by a steel capillary 17.
- the steel capillary 17 is used to couple a twin fiber
- FIG. 5 a, b a further exemplary embodiment with three sensor fibers 1, 2 and 3 analogous to FIGS. 1, 2 or 3 in longitudinal (FIG. 5 a) and cross section (FIG. 5 b) is shown.
- the Ge-P-doped gradient index fibers 1 and 3 are spliced at positions 18 and 19 onto radiation-hard transmission fibers 6 and 7 and are protected by the biocompatible potting compound 20.
- the PbO fiber 2 is first surrounded by a jacket 21 and then by a metal capillary 22.
- the AI mirror 23 is used for light reflection.
- the method according to claim 1 can be carried out with all the sensors shown.
- the measurement results shown in FIGS. 6, 7 and 8 were achieved with a structure according to FIGS. 5 a, b.
- the tissue-equivalent dose was determined in accordance with the description of the method.
- FIG. 6 shows the effective tissue depth dg as a function of the quotient Q ] 2 of the two dose displays S ⁇ and S2 when the double sensor has been calibrated in the dose maximum of the depth dose distribution.
- One signal S] represents the mean value of the two signals originating from the Ge-P sensors 1 and 3.
- the calibration point is located at the intersection 24 of the dotted lines.
- Detection sensitivity for ionizing radiation as illustrated by the measuring points 27 which differ from one another compared to the measuring points 28.
- the squares 29 represent the result determined in accordance with the method.
- a comparison of the determined values 29 with the dose display of an ionization chamber shown by the solid line 30 shows that the method delivers an almost tissue-equivalent result and is in particular more precise than the result measured by the PbO sensor.
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT96901236T ATE200584T1 (de) | 1995-02-06 | 1996-02-01 | Messverfahren und sensor zur on-line in-vivo bestimmung der gewebeäquivalenten dosis bei der strahlentherapie |
JP8523893A JPH10513559A (ja) | 1995-02-06 | 1996-02-01 | 放射線療法で組織に等価な線量を生きた状態でオンライン測定する測定方法とそのセンサ |
DE59606771T DE59606771D1 (de) | 1995-02-06 | 1996-02-01 | Messverfahren und sensor zur on-line in-vivo bestimmung der gewebeäquivalenten dosis bei der strahlentherapie |
EP96901236A EP0808464B1 (de) | 1995-02-06 | 1996-02-01 | Messverfahren und sensor zur on-line in-vivo bestimmung der gewebeäquivalenten dosis bei der strahlentherapie |
US08/894,568 US5938605A (en) | 1995-02-06 | 1996-02-01 | Measuring process and sensor for on-line in-vivo determination of the tissue-equivalent dose in radiotherapy |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19503647.6 | 1995-02-06 | ||
DE19503647A DE19503647C2 (de) | 1995-02-06 | 1995-02-06 | Meßvorrichtung zur in-vivo und on-line-Bestimmung der gewebeäquivalenten Dosis bei der Strahlentherapie |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1996024859A1 true WO1996024859A1 (de) | 1996-08-15 |
Family
ID=7753167
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/DE1996/000174 WO1996024859A1 (de) | 1995-02-06 | 1996-02-01 | Messverfahren und sensor zur on-line in-vivo bestimmung der gewebeäquivalenten dosis bei der strahlentherapie |
Country Status (6)
Country | Link |
---|---|
US (1) | US5938605A (de) |
EP (1) | EP0808464B1 (de) |
JP (1) | JPH10513559A (de) |
AT (1) | ATE200584T1 (de) |
DE (2) | DE19503647C2 (de) |
WO (1) | WO1996024859A1 (de) |
Families Citing this family (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19528096C2 (de) * | 1995-08-01 | 1999-01-07 | Forschungszentrum Juelich Gmbh | Verfahren und Vorrichtung zur Messung der Eindringtiefe einer Strahlung |
DE19545060C1 (de) * | 1995-12-02 | 1997-04-03 | Forschungszentrum Juelich Gmbh | Sensor zur Messung einer gewebeäquivalenten Strahlendosis |
SE9600360L (sv) * | 1996-02-01 | 1997-03-10 | Goeran Wickman | Anordning vid mätning av absorberad dos i ett joniserande strålfält samt känsligt medium i en jonisationskammare |
JPH10213663A (ja) * | 1997-01-29 | 1998-08-11 | Mitsubishi Electric Corp | 局所線量計 |
DE19857502A1 (de) * | 1998-12-14 | 2000-06-15 | Forschungszentrum Juelich Gmbh | Erhöhung der Strahlungsempfindlichkeit einer Glasfaser |
DE19860524A1 (de) * | 1998-12-29 | 2000-07-13 | Deutsches Krebsforsch | Vorrichtung und Verfahren zur Überprüfung dynamisch erzeugter räumlicher Dosisverteilungen |
US7204796B1 (en) | 2000-02-02 | 2007-04-17 | Northern Digital Inc. | Device for determining the position of body parts and use of the same |
US7373197B2 (en) * | 2000-03-03 | 2008-05-13 | Intramedical Imaging, Llc | Methods and devices to expand applications of intraoperative radiation probes |
SE522162C2 (sv) * | 2002-05-06 | 2004-01-20 | Goergen Nilsson | Metod att utföra in vivo-dosimetri vid IMRT-behandling |
EP1493389A1 (de) * | 2003-07-01 | 2005-01-05 | Siemens Aktiengesellschaft | Verfahren und Einrichtung zum Erzeugen eines Röntgenbildes aus der Fokusregion eines Lithotripters |
US7399977B2 (en) * | 2004-07-23 | 2008-07-15 | University Health Network | Apparatus and method for determining radiation dose |
CA2803827C (en) | 2010-07-07 | 2014-04-08 | University Health Network | Fiber optic radiochromic dosimeter probe and method to make the same |
WO2016049585A1 (en) * | 2014-09-26 | 2016-03-31 | Battelle Memorial Institute | Image quality test article set |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0103835A2 (de) * | 1982-09-21 | 1984-03-28 | Siemens Aktiengesellschaft | Faseroptischer Sensor |
EP0416493A2 (de) * | 1989-09-04 | 1991-03-13 | Forschungszentrum Jülich Gmbh | Verfahren, Sensor und Messeinrichtung zur Messung der Dosis von Kernstrahlung |
US5014708A (en) * | 1988-09-14 | 1991-05-14 | Olympus Optical Co. | Radioactive ray detecting therapeutic apparatus |
EP0608101A2 (de) * | 1993-01-18 | 1994-07-27 | Hamamatsu Photonics K.K. | Szintillationszähler |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5008546A (en) * | 1990-06-18 | 1991-04-16 | The Regents Of The University Of California | Intraoperative beta probe and method of using the same |
EP0993119A1 (de) * | 1998-10-09 | 2000-04-12 | Mitsubishi Semiconductor Europe GmbH | Multiplexer-Schaltung und Analog-Digital-Wandler |
-
1995
- 1995-02-06 DE DE19503647A patent/DE19503647C2/de not_active Expired - Fee Related
-
1996
- 1996-02-01 US US08/894,568 patent/US5938605A/en not_active Expired - Fee Related
- 1996-02-01 DE DE59606771T patent/DE59606771D1/de not_active Expired - Fee Related
- 1996-02-01 JP JP8523893A patent/JPH10513559A/ja active Pending
- 1996-02-01 EP EP96901236A patent/EP0808464B1/de not_active Expired - Lifetime
- 1996-02-01 AT AT96901236T patent/ATE200584T1/de not_active IP Right Cessation
- 1996-02-01 WO PCT/DE1996/000174 patent/WO1996024859A1/de active IP Right Grant
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0103835A2 (de) * | 1982-09-21 | 1984-03-28 | Siemens Aktiengesellschaft | Faseroptischer Sensor |
US5014708A (en) * | 1988-09-14 | 1991-05-14 | Olympus Optical Co. | Radioactive ray detecting therapeutic apparatus |
EP0416493A2 (de) * | 1989-09-04 | 1991-03-13 | Forschungszentrum Jülich Gmbh | Verfahren, Sensor und Messeinrichtung zur Messung der Dosis von Kernstrahlung |
EP0608101A2 (de) * | 1993-01-18 | 1994-07-27 | Hamamatsu Photonics K.K. | Szintillationszähler |
Also Published As
Publication number | Publication date |
---|---|
JPH10513559A (ja) | 1998-12-22 |
DE19503647C2 (de) | 1999-12-16 |
US5938605A (en) | 1999-08-17 |
DE19503647A1 (de) | 1996-08-08 |
ATE200584T1 (de) | 2001-04-15 |
EP0808464B1 (de) | 2001-04-11 |
DE59606771D1 (de) | 2001-05-17 |
EP0808464A1 (de) | 1997-11-26 |
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