EP0036181A1 - Appareil de diagnostic par rayons X comportant une chaîne de télévision à intensificateur d'images - Google Patents

Appareil de diagnostic par rayons X comportant une chaîne de télévision à intensificateur d'images Download PDF

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Publication number
EP0036181A1
EP0036181A1 EP81101799A EP81101799A EP0036181A1 EP 0036181 A1 EP0036181 A1 EP 0036181A1 EP 81101799 A EP81101799 A EP 81101799A EP 81101799 A EP81101799 A EP 81101799A EP 0036181 A1 EP0036181 A1 EP 0036181A1
Authority
EP
European Patent Office
Prior art keywords
ray
ray tube
exposure
values
fluoroscopy
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP81101799A
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German (de)
English (en)
Other versions
EP0036181B1 (fr
Inventor
Klaus Dipl.-Ing. Brunn
Walter Polster
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
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Siemens AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG filed Critical Siemens AG
Publication of EP0036181A1 publication Critical patent/EP0036181A1/fr
Application granted granted Critical
Publication of EP0036181B1 publication Critical patent/EP0036181B1/fr
Expired legal-status Critical Current

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    • 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
    • H05G1/46—Combined control of different quantities, e.g. exposure time as well as voltage or current
    • 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
    • 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
    • H05G1/64—Circuit arrangements for X-ray apparatus incorporating image intensifiers

Definitions

  • the invention relates to an X-ray diagnostic system with an image intensifier television chain, a dose rate control device for fluoroscopy, by means of which the average image brightness during the fluoroscopy is kept constant by means of a fluoroscopy parameter, and an automatic exposure device with an integrator for forming a signal corresponding to the respective X-ray dose per image, which is via a Switching stage switches off the X-ray radiation when a predetermined dose value is reached and with means for adjusting the X-ray tube voltage as a function of the patient's transparency.
  • X-ray diagnostic system of this type is described in DE-AS 19 29 894.
  • the X-ray tube voltage is influenced when a predetermined time window for the recording time of an X-ray recording is exceeded or undershot so that the recording time of the image following an adjustment process is again within the limits specified by the time window.
  • a predetermined time window for the recording time of an X-ray recording is exceeded or undershot so that the recording time of the image following an adjustment process is again within the limits specified by the time window.
  • the invention has for its object to design an X-ray diagnostic system of the type mentioned in such a way that an automatic adjustment of all exposure values to the respective patient transparency, whereby an optimal utilization of the resilience of the X-ray tube is given.
  • a storage device in which a pair of values for the x-ray tube power and the exposure time is stored for each patient transparency and further exposure values, in that a transparency signal is supplied to this storage device, which signal signals at least one during an x-ray exposure or exposure series previous fluoroscopy automatically adjusted fluoroscopy parameters and the corresponding stored value pair generates corresponding signals at the output of the storage device, which are fed to the x-ray generator for adjustment and that a detector is present, which changes the value pair retrieved when the exposure time switched by the exposure machine from the retrieved exposure time deviates by a predetermined amount.
  • a signal is derived from a fluoroscopic value, for example the X-ray tube voltage, during a fluoroscopy preceding an X-ray or series of recordings, which embodies the transparency of the patient.
  • This signal then causes the X-ray tube power and the recording time to be set automatically for a recording or series of recordings.
  • an optimal pair of values for the X-ray tube performance and the exposure time can be programmed so that the load capacity of the X-ray tube is fully utilized.
  • a further development of the invention is that a function generator for the in the memory device Definition of a time window for the recording time depending on the transparency signal is present.
  • the set of values for the x-ray tube power and the time window is not corrected if the switched recording time is within the time window.
  • the time window is exceeded up or down, the pair of values is changed so that the next time the picture is taken, the recording time is within the time window. If it is no longer possible to change the pair of values, the x-ray tube voltage can also be influenced to adapt to the patient's transparency.
  • a further embodiment of the invention consists in that means for the free adjustment of the x-ray tube voltage are provided, which provide correction signals for the other recording values to prevent overloading the x-ray tube.
  • FIG. 1 shows an X-ray generator 1 that feeds an X-ray tube 2, which shines through a patient 3 and generates an X-ray silhouette on the fluorescent screen of an X-ray image intensifier 4.
  • the output image of the X-ray image intensifier 4 becomes a film via a semi-transparent mirror 9 camera 6 and a television camera 7 supplied.
  • the television camera 7 generates a fluoroscopic image on a television monitor 8.
  • a mirror 5 which is also semi-transparent and which is a photo.
  • multiplier 10 supplies a light signal corresponding to the average image brightness.
  • This light signal is from the photomultiplier. 10 converted into a corresponding electrical signal appearing at its output 11.
  • This signal can be fed via a switch 12 during the fluoroscopy of a dose rate control device 13, which changes the fluoroscopy values, that is to say the X-ray tube current and the X-ray tube voltage, during a fluoroscopy in such a way that the average image brightness remains constant.
  • a switch 12 changes the fluoroscopy values, that is to say the X-ray tube current and the X-ray tube voltage, during a fluoroscopy in such a way that the average image brightness remains constant.
  • At its output 14 it delivers a transparency signal corresponding to the respective fluoroscopic values and thus the patient transparency.
  • the photomultiplier 10 supplies a signal to an integrator 15 in its dashed position via the switch 12, which signal is converted by integration into a signal corresponding to the radiation dose, which signal is fed to a threshold switch 16.
  • the threshold switch 16 supplies the X-ray generator 1 with a switch-off signal when a predetermined radiation dose has been reached; it sets the exposure time for an x-ray.
  • the components 10, 15 and 16 thus form an automatic exposure device for forming a signal corresponding to the x-ray dose per image, which, via the threshold value switch 16 as a switching stage, switches off the x-ray radiation when a predetermined dose value is reached.
  • a time window detector 17 is connected to the threshold switch 16 and specifies an adjustable time window for the exposure time of an X-ray exposure.
  • a switch 18 is flipped into its position shown in dashed lines, so that the exposure values can be corrected in the manner described below if the exposure time switched by the automatic exposure device exceeds the respectively predetermined time window upwards or downwards.
  • a line leads from the switch 18 to a memory 19, in which information for a function generator 20 is stored for each transparency.
  • the dependency of the time window and the x-ray tube power on the transparency is stored in the function generator 20.
  • a signal corresponding to the time window is present at output 21 and a signal corresponding to the x-ray tube power is present at output 22
  • switches 12 and 18 assume their fully drawn positions.
  • the mean image brightness is kept constant and the memory 19 receives a signal corresponding to the transparency via the line 14, so that it supplies the function generator 20 with information corresponding to the transparency.
  • the function generator 20 and the components 15, 16, 17 are switched off by the generator 1 during fluoroscopy.
  • the switches 12 and 18 are flipped into their positions shown in dashed lines.
  • the x-ray tube power is set via the function generator 20.
  • the window detector 17 receives one of the time window width and the upper and lower limits of the Time window corresponding signal, these values are also determined depending on the transparency.
  • the window detector 17 now monitors during an X-ray exposure in a cinema scene, whether the exposure time is within the time window defined by the function generator 20. If this is not the case, it influences the memory 19 via line 23, i.e. depending on the actually switched recording time, he selects a new transparency information from the memory 19, which queries the function generator 20 for a new pair of values for the time window and the X-ray tube power. This new pair of values is then set in the X-ray generator 1 and entered in the window detector 17. If the recording time is within the new time window, then no correction is made, in the other case a correction is made again, until the recording time is within the time window.
  • the signal generator 20 is fed via a line 24 to the image frequency, via a line 25 to the scene time and via a line 26 to a signal corresponding to the selected focus of the x-ray tube, which in addition to the transparency signal on line 19a also selects the pair of values for the x-ray tube power and causes the recording time.
  • the x-ray tube voltage is also automatically determined depending on the transparency of the patient.
  • a kV memory 27 is provided, which receives a signal corresponding to the patient transparency at the input 28 and in which for. each patient transparency an optimal x-ray tube performance is stored.
  • a signal corresponding to the retrieved x-ray tube voltage effects the adjustment of the x-rays via line 29 tube voltage in the x-ray generator 1.
  • the function generator 20 receives a signal corresponding to the called x-ray tube voltage via the line 30, so that it can set the pair of values of x-ray tube power and exposure time required for the correct exposure and permissible for a series of exposures.
  • the x-ray tube voltage is corrected via line 31, ie a new suitable x-ray tube voltage value im kV memory 27 accessed.
  • An adjustment device 32 for the free adjustment of the x-ray tube voltage is connected to the kV memory 27. If this free setting is made, the function generator 20 receives a correction via the line 30. tursignal, so that the recording time, i.e. the time window, and the X-ray tube power are determined so that the correct exposure is maintained (i.e. dose per image is constant) and overloading of the X-ray tube is certainly prevented. This overload is always prevented with certainty even during the automatic adjustment of the x-ray tube voltage, because for each patient transparency only such value pairs from the exposure time and x-ray tube power are queried from the function generator 20 and only such an x-ray tube voltage is set via the kV memory 27 that the x-ray tube 2 is not overloaded.
  • FIGS. 2 to 4 show four transparency areas I to IV of a patient.
  • Figure 2 shows the course of the x-ray tube voltage from the patient thickness, which is programmed in the kV memory 27;
  • FIG. 3 shows the course of the time window as a function of the patient thickness and
  • FIG. 4 shows the course of the X-ray tube power from the patient thickness.
  • the area I corresponds to a very thin patient and the area IV to a very thick patient.
  • the patient thicknesses assigned to areas I to IV thus increase from I to IV.
  • FIG. 3 shows that, depending on the patient thickness, pairs of values from approximately constant recording time and increasing X-ray tube output are initially programmed (area I), that increasing values of the recording time are then defined in area II with constant X-ray tube output, and then in area III with decreasing X-ray tube output further increasing recording times are specified and that finally the x-ray tube voltage increases with reduced constant x-ray tube power and constant recording time.
  • area IV the described retrieval of new x-ray tube voltage values from the kV memory 27 takes place by the function generator 20.
  • a time window is specified for the exposure time switched by the automatic exposure device 10, 15, 16. If the recording time is within the time window, there is no correction of the pair of values from the recording time (time window) and X-ray tube output, nor is there any correction of the X-ray tube voltage. In the other case, at least the pair of values from the recording time and the X-ray tube power, and possibly also the X-ray tube voltage (area IV), is changed so that the next time after the change, the recording time is again within the time window. It is also possible not to specify a time window, but rather a single recording time value from the function generator 20. In this case, a correction is made if the recording time actually switched does not match the specified recording time value.
  • the time window is predetermined by a function generator in the function generator 20.
  • a function generator is also present in the function generator 20 for the X-ray tube power.
  • the corresponding functions are shown in FIG. 1 in the function generator 20. They correspond to the functions according to FIGS. 3 and 4.
  • the adjustment of the x-ray tube voltage via the kV memory 27 is of course only carried out in the recording mode. In fluoroscopic mode, this task is performed by the dose rate control device 13.

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  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • X-Ray Techniques (AREA)
EP81101799A 1980-03-14 1981-03-11 Appareil de diagnostic par rayons X comportant une chaîne de télévision à intensificateur d'images Expired EP0036181B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3009952 1980-03-14
DE19803009952 DE3009952A1 (de) 1980-03-14 1980-03-14 Roentgendiagnostikanlage mit einer bildverstaerker-fernsehkette

Publications (2)

Publication Number Publication Date
EP0036181A1 true EP0036181A1 (fr) 1981-09-23
EP0036181B1 EP0036181B1 (fr) 1983-07-06

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EP81101799A Expired EP0036181B1 (fr) 1980-03-14 1981-03-11 Appareil de diagnostic par rayons X comportant une chaîne de télévision à intensificateur d'images

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US (1) US4649558A (fr)
EP (1) EP0036181B1 (fr)
DE (2) DE3009952A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3506389A1 (de) * 1984-05-29 1985-12-05 VEB Transformatoren- und Röntgenwerk "Hermann Matern", DDR 8030 Dresden Roentgendiagnostikeinrichtung mit einer bildverstaerker-fernsehkette
EP0564551A1 (fr) * 1990-12-28 1993-10-13 Fisher Imaging Corp Commande dynamique d'impulsions utilisee en fluoroscopie.

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4821727A (en) * 1986-10-30 1989-04-18 Elscint Ltd. Mammographic biopsy needle holder system
US5966425A (en) * 1989-12-07 1999-10-12 Electromed International Apparatus and method for automatic X-ray control
JPH0458498A (ja) * 1990-06-25 1992-02-25 Toshiba Corp Ｘ線診断装置
US5917882A (en) * 1996-11-29 1999-06-29 Continental X-Ray Corporation Radiographic/fluoroscopic imaging system with reduced patient dose and faster transitions between radiographic and fluoroscopic modes
US7372940B2 (en) * 2005-09-30 2008-05-13 Topel, Llc Radiation therapy system with risk mitigation
FR2926823B1 (fr) * 2008-01-24 2010-06-11 Superba Sa Dispositif de positionnement du tapis transporteur en defilement dans des machines de traitement thermique de fils
US8845190B2 (en) * 2010-10-06 2014-09-30 Carestream Health, Inc. Low-dose automatic exposure control system for digital portable X-ray imaging
DE102011087127B4 (de) * 2011-11-25 2015-11-19 Siemens Aktiengesellschaft Bestimmung von Aufnahmeparametern bei einer Dual-Energy Tomosynthese
EP3574311A4 (fr) * 2017-08-04 2020-11-18 Hewlett-Packard Development Company, L.P. Transmissions de données alimentées par rayons x

Citations (9)

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DE1929894A1 (de) * 1968-09-13 1970-07-23 Litton Industries Inc Kinematographische Roentgenstrahleinrichtung
DE2204453A1 (de) * 1972-01-31 1973-08-09 Siemens Ag Roentgendiagnostikapparat mit einer bildverstaerker-fernsehkette und einem regelkreis fuer die dosisleistung nach dem patienten
DE2245939A1 (de) * 1972-09-19 1974-04-11 Siemens Ag Roentgendiagnostikapparat zur durchleuchtung und aufnahme
DE2350391A1 (de) * 1973-10-08 1975-04-17 Philips Patentverwaltung Roentgengenerator fuer ein schichtaufnahmegeraet
DE2550911A1 (de) * 1975-04-15 1976-10-28 Transform Roentgen Matern Veb Ueberlastungsschutzeinrichtung fuer roentgenroehren von roentgen-diagnostik- generatoren
US4035649A (en) * 1973-10-08 1977-07-12 U.S. Philips Corporation X-ray generator for a tomography apparatus
DE2650872A1 (de) * 1976-11-06 1978-05-11 Philips Patentverwaltung Roentgengenerator fuer ein schichtaufnahmegeraet
DE2653252A1 (de) * 1976-11-24 1978-06-01 Philips Patentverwaltung Roentgendiagnostikgenerator mit einer dosisleistungsmesseinrichtung
DE2827146A1 (de) * 1977-06-23 1979-01-11 Gen Electric Anatomisch koordinierter, vom benutzer beherrschter programmierer fuer eine diagnostische roentgenvorrichtung

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Publication number Priority date Publication date Assignee Title
DE2855405A1 (de) * 1978-12-21 1980-07-10 Siemens Ag Roentgendiagnostikapparat zur durchleuchtung und aufnahme
DE3006049C2 (de) * 1980-02-18 1984-04-12 Siemens AG, 1000 Berlin und 8000 München Röntgendiagnostikanlage für Röntgenaufnahmen mit einem Röntgenbildverstärker, einer Filmkamera und einem Belichtungsautomaten

Patent Citations (15)

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Publication number Priority date Publication date Assignee Title
US3546461A (en) * 1968-09-13 1970-12-08 Litton Medical Products Automatic control of a nonsynchronous cine fluororadiographic apparatus
DE1929894A1 (de) * 1968-09-13 1970-07-23 Litton Industries Inc Kinematographische Roentgenstrahleinrichtung
DE2204453A1 (de) * 1972-01-31 1973-08-09 Siemens Ag Roentgendiagnostikapparat mit einer bildverstaerker-fernsehkette und einem regelkreis fuer die dosisleistung nach dem patienten
FR2169962A1 (fr) * 1972-01-31 1973-09-14 Siemens Ag
DE2245939A1 (de) * 1972-09-19 1974-04-11 Siemens Ag Roentgendiagnostikapparat zur durchleuchtung und aufnahme
US3991314A (en) * 1972-09-19 1976-11-09 Siemens Aktiengesellschaft X-ray diagnosis apparatus for X-raying and exposure
US4035649A (en) * 1973-10-08 1977-07-12 U.S. Philips Corporation X-ray generator for a tomography apparatus
DE2350391A1 (de) * 1973-10-08 1975-04-17 Philips Patentverwaltung Roentgengenerator fuer ein schichtaufnahmegeraet
DE2550911A1 (de) * 1975-04-15 1976-10-28 Transform Roentgen Matern Veb Ueberlastungsschutzeinrichtung fuer roentgenroehren von roentgen-diagnostik- generatoren
DE2650872A1 (de) * 1976-11-06 1978-05-11 Philips Patentverwaltung Roentgengenerator fuer ein schichtaufnahmegeraet
DE2653252A1 (de) * 1976-11-24 1978-06-01 Philips Patentverwaltung Roentgendiagnostikgenerator mit einer dosisleistungsmesseinrichtung
FR2372570A1 (fr) * 1976-11-24 1978-06-23 Philips Nv Generateur utilise pour le radiodiagnostic et muni d'un dispositif pour mesurer le debit de rayonnement
DE2827146A1 (de) * 1977-06-23 1979-01-11 Gen Electric Anatomisch koordinierter, vom benutzer beherrschter programmierer fuer eine diagnostische roentgenvorrichtung
FR2395669A1 (fr) * 1977-06-23 1979-01-19 Gen Electric Systeme de diagnostic pour rayons x programme sur base de l'anatomie
US4160906A (en) * 1977-06-23 1979-07-10 General Electric Company Anatomically coordinated user dominated programmer for diagnostic x-ray apparatus

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3506389A1 (de) * 1984-05-29 1985-12-05 VEB Transformatoren- und Röntgenwerk "Hermann Matern", DDR 8030 Dresden Roentgendiagnostikeinrichtung mit einer bildverstaerker-fernsehkette
EP0564551A1 (fr) * 1990-12-28 1993-10-13 Fisher Imaging Corp Commande dynamique d'impulsions utilisee en fluoroscopie.
EP0564551A4 (fr) * 1990-12-28 1994-03-09 Fisher Imaging Corporation

Also Published As

Publication number Publication date
DE3009952A1 (de) 1981-09-24
US4649558A (en) 1987-03-10
DE3160551D1 (en) 1983-08-11
EP0036181B1 (fr) 1983-07-06

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