EP0036181B1 - 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
EP0036181B1
EP0036181B1 EP81101799A EP81101799A EP0036181B1 EP 0036181 B1 EP0036181 B1 EP 0036181B1 EP 81101799 A EP81101799 A EP 81101799A EP 81101799 A EP81101799 A EP 81101799A EP 0036181 B1 EP0036181 B1 EP 0036181B1
Authority
EP
European Patent Office
Prior art keywords
ray
ray tube
transparency
signal
recording
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.)
Expired
Application number
EP81101799A
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German (de)
English (en)
Other versions
EP0036181A1 (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, with a dose rate control device for fluoroscopy, by means of which the average image brightness during the fluoroscopy is kept constant via the X-ray tube power, with an automatic exposure device, which has an integrator for forming a signal corresponding to the respective X-ray dose per image , which causes the X-ray radiation to be switched off when a predetermined dose value for an X-ray exposure is reached, with means for adjusting the X-ray tube voltage as a function of the patient's transparency, and with a storage device which can be supplied with a transparency signal corresponding to the patient's transparency, which is used by the patient corresponds to the X-ray tube power automatically set for an X-ray exposure or X-ray exposure series preceding the X-ray exposure, and that abr a signal at the output of the memory device uft that can be fed to the X-ray generator for adjustment.
  • DE-A-1 929 894 discloses 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 is kept constant during fluoroscopy via a fluoroscopy parameter, and an automatic exposure device with an integrator for forming one of the respective X-ray doses for each image, the corresponding signal, which causes the X-ray radiation to be switched off 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.
  • 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.
  • the invention is based on the object of designing an X-ray diagnostic system of the type mentioned at the outset in such a way that all the exposure values are automatically adapted to the respective patient transparency, with optimal utilization of the resilience of the X-ray tube.
  • This object is achieved according to the invention in that in the memory device for predetermined values of patient transparency and further recording parameters, a pair of values for the x-ray tube power and the recording time, which are matched to the x-ray tube load capacity, are stored in that the output signal of the memory device of the x-ray tube power of the retrieved value pair that can be fed to the x-ray generator is stored and that the transparency signal also calls at the output of the storage device a further signal which corresponds to the exposure time of the retrieved pair of values and which can be fed to a detector which in turn retrieves new stored pairs of values until the difference between the exposure time switched by the exposure machine and the retrieved recording time does not exceed a predetermined level.
  • a signal is derived from a fluoroscopic value, for example the X-ray tube voltage, 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 consists in that a function generator for defining a time window for the recording time and the x-ray tube power belonging to the respective time window is present in the memory device as a function of the transparency signal.
  • 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 will go up or down exceeded, the pair of values is changed so that the next time the recording is made, 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 are provided for the free adjustment of the x-ray tube voltage, which provide correction signals for the storage device, so that the dose per image remains constant and an overload of the x-ray tube is prevented.
  • X-ray generator 1 which feeds an X-ray tube 2, which shines through a patient 3 and generates an X-ray silhouette on the input fluorescent screen of an X-ray image intensifier 4.
  • the output image of the X-ray image intensifier 4 is fed to a film camera 6 and a television camera 7 via a semi-transparent mirror 9.
  • the television camera 7 generates a fluoroscopic image on a television monitor 8.
  • 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 average 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 a signal corresponding to the time window width and the upper and lower limits of the time window, these values also being determined as a function of the transparency.
  • the window detector 17 now monitors during an X-ray exposure in a cinema scene whether the exposure time lies within the time window defined by the function generator 20. If this is not the case, it influences the memory 19 via the line 23, that is to say it selects a new transparency information item from the memory 19 as a function of the actually switched recording time, and the function generator 20 selects a new pair of values for the time window and the X-ray tube power queries. 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, no correction is made, in the other case a correction is made again until the recording time is within the time window.
  • the function generator 20 is connected via a line 24 to the frame rate, via a line 25 to the scene time and via a Line 26 is supplied with a signal corresponding to the selected focus of the X-ray tube, which in addition to the transparency signal on line 19a causes the selection of the pair of values for the X-ray tube power and 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 an optimal X-ray tube performance is stored for each patient transparency.
  • a signal corresponding to the retrieved x-ray tube voltage causes the setting of the x-ray tube voltage in the x-ray generator 1 via line 29.
  • the function generator 20 receives via line 30 a signal corresponding to the retrieved x-ray tube voltage, so that it provides the value pair required for the correct exposure and permissible for a series of exposures from X-ray tube power and recording time.
  • the switched recording time deviates impermissibly from the time called in the function generator 20, but a correction via the X-ray tube power and the time window, i. H. the pulse width is no longer possible for an X-ray exposure, the X-ray tube voltage is corrected via line 31, i. H. a new suitable x-ray tube voltage value is retrieved in the kV memory 27.
  • 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 signal via the line 30, so that the recording time, that is to say the time window, and the X-ray tube power are determined in such a way that the correct exposure is maintained (ie dose per image is constant) and with Safety prevents an overload of the x-ray tube. 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 does not is overloaded.
  • FIG. 2 to 4 show four transparency areas I to IV of a patient.
  • 2 shows the course of the x-ray tube voltage (kV) as a function of the patient thickness, which is programmed in the kV memory 27;
  • FIG. 3 shows the course of the time window (ms) as a function of the patient thickness and
  • FIG. 4 shows the course of the X-ray tube power (kW) as a function of 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's 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 111 when the number decreases X-ray tube power further increasing recording times are given 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 exposure machines 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 power, nor is there any correction of the X-ray tube voltage. In the other case, at least the pair of values consisting of the recording time and the X-ray tube power, possibly also the X-ray tube voltage (area IV), is changed, so that the next time the image is taken, 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)

Claims (3)

1. Installation de radiodiagnostic avec une chaîne de télévision à amplificateur de brillance (7, 8), avec un dispositif de réglage du débit de dose (4, 5, 10, 13) pour la radioscopie et à l'aide duquel est maintenue constante la luminosité de l'image, par rapport à la puissance du tube à rayons X, avec un régulateur automatique du temps d'exposition (10, 15, 16) qui comporte un intégrateur (15) pour former un signal qui correspond à la dose de rayons X par image et qui, par l'intermédiaire d'un étage de commutation (16), provoque le débranchement du rayonnement X lorsqu'est atteinte une valeur de dose prédéterminée pour une radiographie, avec des moyens (27, 29) pour régler la tension du tube à rayons X pour une prise de vue en fonction de la transparence du patient, et avec un dispositif à mémoire (19, 20) auquel est susceptible d'être appliqué un signal de transparence qui correspond à la transparence du patient, signal de transparence qui correspond à la puissance du tube à rayons X qui a été réglée automatiquement lors d'une radioscopie qui a précédé une radiographie ou une série de radiographies, et qui prélève, à la sortie du dispositif à mémoire (19, 20), un signal qui est susceptible d'être appliqué au générateur radiologique (1) pour le réglage de ce dernier, caractérisée par le fait que dans le dispositif à mémoire (19, 20) est mémorisée, pour des valeurs prédéterminées de la transparence du patient et pour d'autres paramètres de la prise de vue, respectivement une paire de valeurs pour la puissance du tube à rayons X et pour le temps d'exposition, adaptée à la charge admissible pour le tube à rayons X, que le signal de sortie du dispositif à mémoire (19, 20) qui est susceptible d'être appliqué au générateur radiologique (1) correspond à la puissance du tube à rayons X de la paire de valeurs prélevée, et que le signal de transparence prélève, en outre, à la sortie du dispositif à mémoire, un signal supplémentaire qui correspond à la durée d'exposition de la paire de valeurs prélevée et qui est susceptible d'être appliqué à un détecteur (17) qui, à son tour, prélève de nouvelles paires de valeurs jusqu'à ce que l'écart entre la durée d'exposition commutée par le régulateur automatique du temps d'exposition (10, 15, 16) et la durée d'exposition prélevée, ne dépasse pas une valeur prédéterminée.
2. Installation de radiodiagnostic selon la revendication 1, caractérisée par le fait que le dispositif à mémoire (19, 20) comporte un générateur de fonction pour déterminer un créneau temporel pour la durée d'exposition et la puissance du tube à rayons X associée au créneau temporel concerné, en fonction du signal de transparence.
3. Installation de radiodiagnostic selon la revendication 1 ou 2, caractérisée par le fait que sont prévus des moyens (32, 27) pour le libre réglage de la tension du tube à rayons X, et qui fournissent les signaux de correction pour le dispositif à mémoire (19,20), afin que la dose par image reste constante et pour que soit empêchée une surcharge du tube à rayons X.
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)

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EP0036181A1 EP0036181A1 (fr) 1981-09-23
EP0036181B1 true 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)

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DD225307A1 (de) * 1984-05-29 1985-07-24 Transform Roentgen Matern Veb Roentgendiagnostikeinrichtung mit einer bildverstaerker-fernsehkette
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
US5119409A (en) * 1990-12-28 1992-06-02 Fischer Imaging Corporation Dynamic pulse control for fluoroscopy
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

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US3546461A (en) * 1968-09-13 1970-12-08 Litton Medical Products Automatic control of a nonsynchronous cine fluororadiographic apparatus
DE2204453B2 (de) * 1972-01-31 1977-09-01 Siemens AG, 1000 Berlin und 8000 München Roentgendiagnostikapparat mit einer bildverstaerker-fernsehkette und einem die dosisleistung nach dem patienten einstellenden regelkreis
DE2245939B2 (de) * 1972-09-19 1976-07-22 Siemens AG, 1000 Berlin und 8000 München Roentgendiagnostikapparat zur durchleuchtung und aufnahme mit einem funktionsgenerator zur festlegung der aufnahmespannung in abhaengigkeit von der durchleuchtungsspannung
DE2350391A1 (de) * 1973-10-08 1975-04-17 Philips Patentverwaltung Roentgengenerator fuer ein schichtaufnahmegeraet
US4035649A (en) * 1973-10-08 1977-07-12 U.S. Philips Corporation X-ray generator for a tomography apparatus
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US4160906A (en) * 1977-06-23 1979-07-10 General Electric Company Anatomically coordinated user dominated programmer for diagnostic x-ray apparatus
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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

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Publication number Publication date
EP0036181A1 (fr) 1981-09-23
DE3009952A1 (de) 1981-09-24
US4649558A (en) 1987-03-10
DE3160551D1 (en) 1983-08-11

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