EP1166148A1 - Procede et dispositif d'echographie 3d en temps reel - Google Patents

Procede et dispositif d'echographie 3d en temps reel

Info

Publication number
EP1166148A1
EP1166148A1 EP00918814A EP00918814A EP1166148A1 EP 1166148 A1 EP1166148 A1 EP 1166148A1 EP 00918814 A EP00918814 A EP 00918814A EP 00918814 A EP00918814 A EP 00918814A EP 1166148 A1 EP1166148 A1 EP 1166148A1
Authority
EP
European Patent Office
Prior art keywords
real
transmission signal
receivers
signal
determining
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.)
Withdrawn
Application number
EP00918814A
Other languages
German (de)
English (en)
Inventor
Miroslaw Wrobel
Eckard Glaser
Janet Grassmann
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.)
Son Em GmbH
Original Assignee
Son Em GmbH
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 Son Em GmbH filed Critical Son Em GmbH
Publication of EP1166148A1 publication Critical patent/EP1166148A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B42/00—Obtaining records using waves other than optical waves; Visualisation of such records by using optical means
    • G03B42/06—Obtaining records using waves other than optical waves; Visualisation of such records by using optical means using ultrasonic, sonic or infrasonic waves
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
    • G01S15/88—Sonar systems specially adapted for specific applications
    • G01S15/89—Sonar systems specially adapted for specific applications for mapping or imaging
    • G01S15/8906—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques
    • G01S15/8993—Three dimensional imaging systems

Definitions

  • the invention relates to a device and a method for 3D real-time sonography with an ultrasound head, signal processing and a display device, in which the speed of data acquisition via unknown structures is only limited by the physics of the sound conductor in the respective body.
  • Application emits an ultrasound pulse into a tissue and the returning echo pulses are evaluated in relation to the transit time in order to determine the depth and the extent or the course of a specific structure on which the reflections arise.
  • Ultrasound diagnostics use ultrasound heads, which in the best known versions consist of a linear arrangement of individual mechanically separated piezo elements.
  • the piezo elements send a pulse train into the tissue and then continuously receive the returning echo signals within a defined period of time.
  • the same piezo elements then act as pressure sensors for receiving the echo pulses. The time period is determined by the last echo signal arriving at the sensor from the deepest reflection zone.
  • the same piezo elements generally serve both as a transmitter and as a receiver.
  • certain structures may then be recognizable, which in most cases can only be assessed precisely on the basis of the doctor's extensive experience.
  • U.S. Patent 5,601,083 describes a device that uses ellipsoidal back projection to improve resolution.
  • the device has a receiver array in which each receiving element corresponds to a reconstruction pixel angle.
  • the echoes picked up by the receiver are weighted in an amplitude function generator as a function of the reconstruction pixel angle.
  • an image is reconstructed and displayed from the weighted echoes.
  • three-dimensional imaging has undergone a decisive further development.
  • the three-dimensional images are calculated from individual images using the methods that have become known. The main problem so far has been the very high time required for the calculation of these images.
  • By providing fast computers larger image sequences with over 30 images can now be easily calculated within approx. 10 - 15 s.
  • a special transducer contains e.g. a motor that swivels the inner array sound element by 10 ° to 95 ° depending on the type of head at the push of a button. This gives you a large number of cutting planes that are equidistant from each other.
  • the recorded echoes are stored as digital signals in a volume memory.
  • the recording time is between 0.3 s and 2 min. All section planes within the respective volume can then be calculated and displayed from the volume memory.
  • the three-dimensional images can then be displayed one after the other on the monitor either as single images or in the form of a rotation animation.
  • the volume data are recorded externally.
  • the movement of the sound element is coupled to a position transmitter.
  • the transducer can then also be moved by hand. Together with the image data, the Image position can be captured and saved.
  • a standard transducer can then be used, but the system is very bulky and requires a lot of time to acquire the image data. Since the distance between the individual two-dimensional images is not identical, the cutting planes can overlap, which leads to poor display.
  • the object of the present invention is to provide a device which realizes high image quality and fast data acquisition and enables 3D visualization in real time.
  • the object is achieved with the aid of a device for 3D real-time sonography according to claim 1 and a method according to claim 7.
  • the device consists of an ultrasound head, a signal processing and a display device, in which the ultrasound head consists of at least one transmitter and separately at least three receivers, the positions of which are known to the transmitters, the signal processing from a signal generator for generating a transmission signal with any modulation function , one Correlator on each receiver, each connected to the signal generator, a calculation unit for determining the paths of the transmission signal via the reflective structure to the receivers on each correlator, and a calculation unit for determining the spatial coordinates of the reflective structure to which each calculation unit for the determination of the paths of the transmission signal via the reflective structure to the receivers is connected.
  • the user is completely free to choose where to place the transmitter or receivers on the medium with the structure to be examined. This makes it possible to determine the most favorable "viewing and illumination angles" of a structure lying in the interior of a medium. If at least three receivers are arranged in one plane and this is determined as the "viewing window", i.e. as the reference level for all transmitters, a shadow-free image of a structure embedded in a medium can be generated.
  • the user is also free to choose how many transmitters and how many receivers are arranged. For a three-dimensional display, however, at least one transmitter and three receivers or three transmitters and one receiver are required.
  • the transmitters and receivers can e.g. can also be arranged so that the transmission signal hits the structure from the side or the medium lies between the transmitters and the receivers.
  • the echo signals are then essentially influenced by the absorption quality of the medium and the structure to be examined. If there are several transmitters, echo signals can be received which reflect both the quality of absorption and the quality of reflection of a structure.
  • the device for 3D real-time sonography is between the transmitter or transmitters and the Correlator and each receiver and the correlator an A / D converter arranged.
  • the transmission signals and the receiver signals are digitized and then digitally processed.
  • the device for the 3D real-time sonography can contain a memory which stores the digitized transmission signals in order to have them available in the same form for every further sonication process.
  • the memory is connected to the generator directly or via a control unit.
  • the control unit can be designed in such a way that it can be triggered manually or automatically.
  • the invention also includes a method for 3D real-time sonography, in which ultrasound signals are emitted from an ultrasound head into a medium and the echo signals are received and displayed on an image unit, the method comprising the following steps: a) emitting a transmission signal with any modulation function from at least one transmitter into a medium; b) receiving the echo signals from at least three receivers which are arranged separately from the transmitters and whose positions to the transmitters are known; c) correlation of the echo signals with the transmission signal for determining the paths of the transmission signal from the transmitter via a reflective structure in the medium to the respective receivers, by determining the pattern features of the transmission signal in the echo signals; d) determining the spatial coordinates and the quality of reflection and / or absorption of the reflective structure from the results of step c) using triangulation; and e) displaying the spatial coordinates and the reflection and / or Absorption quality of the reflective structure on a display device.
  • the individual transmitters must transmit the transmission signals one after the other so that the “lighting directions” can be distinguished from the receivers. If transmission signals with different modulation functions are transmitted, they can the transmitters simultaneously emit their transmission signal into the medium.
  • the transmission signal Due to the separation of the receiver from the transmitter, the transmission signal has no length limit. Its duration is only limited by the modulation function.
  • the transmission signal and the echo signals are digitized before the correlation.
  • Wavelet methods are used, or neural networks can be used, with the aid of which the characteristics of the transmission signal are searched for in the echo signals.
  • the method for 3D real-time sonography is also expanded if the transmission signals are stored in a memory and are used to control the transmission generator for renewed generation of the same transmission signals. This method step is particularly favorable if a body is first irradiated with a transmission signal with a freely adjustable modulation function until recognizable reflections become visible on the display device. In the case of repetitions, the transmission signal can then be called up from the memory as often as desired using the same modulation function.
  • Each echo signal is a superposition of the reflection signals from the volume.
  • the echo signals are processed separately in each channel and correlated with the respective transmission signal.
  • the path from the transmitter via the reflection points to the individual receivers must first be determined.
  • the echo signals are correlated with the transmission signal.
  • the resulting signal shows a certain signal pattern at the times when a reflected signal arrives. From these points in time, the ellipses or ellipsoids are determined, which are determined further by the path of the transmission signal up to the reflection points to the receivers, the transmitter and the receiver being in the focal points of the respective ellipses or ellipsoids.
  • the spatial coordinates of the reflection points result from the intersection points of the individual ellipsoids belonging to the receivers.
  • the decisive difference to the conventional methods lies in the fact that the individual levels of the reflections are not recorded one after the other, but all data are recorded simultaneously. That fact is an essential prerequisite for real-time sonography that has not yet been realized. This makes it possible for the first time to track moving structures in real time, for example the movement of the heart valves as a 3D image in slow motion. This gives the cardiologist and the gynecologist very important instruments.
  • the depth of penetration decreases with increasing frequency.
  • This fundamental contradiction is inherent in the investigation of living matter.
  • the contradiction can be reduced if the sound energy is increased, but this is only possible to a limited extent in living matter.
  • the inventive solution offers the possibility of achieving a very high resolution with a large penetration depth.
  • Ultrasound diagnostics can thus be carried out with very low energies and thus with the least possible strain on the patient.
  • the maximum resolution is 1.5 mm with a penetration depth of approximately 20 cm.
  • the resolution is constant 0.1 mm.
  • the resolution can be increased to 0.05 mm.
  • An arbitrarily modulated ultrasound signal (e.g. also a growing or falling frequency sequence - based on the method of echolocation used in bats and dolphins) is emitted.
  • the information for the entire image volume can be obtained with a single such signal, the time required for this depending on the depth of the
  • Structure in the medium can be in the microsecond range.
  • the echo signals are recorded "in parallel" and are therefore much more time-efficient than with the conventional methods.
  • Another decisive advantage is that the representation of the detected structures contains significantly fewer noise components. This makes the display significantly clearer, meaning that the experience of a doctor is no longer decisive for the assessment of a sonogram. Since primarily signal processing and no image processing takes place - as in the conventional methods - the entire information content is retained. A falsification of the representation is therefore excluded.
  • Another advantage, particularly for the examination of living tissue, is the possibility of using very low energies with which the body must be sonicated. This eliminates the crucial disadvantage of all previous methods that only improve resolution by increasing energy.
  • FIG. 1 shows a block diagram of a device for 3D real-time sonography according to the present invention with analog transmit signals and corresponding analog processing of the echo signals;
  • FIG. 2 shows a block diagram of a device for 3D real-time sonography according to the present invention with digital processing of the echo signals;
  • 3A and 3B show a special transmission signal referred to as "chirp" and the corresponding echo signal;
  • FIG. 4 shows an echo signal of the “chirp” according to FIG. 3, which was reflected by 3 points;
  • FIG. 5 shows the result of the correlation of the "chirp" according to Fig. 3 with the echo signal according to Fig. 4;
  • Fig. 6 shows an echo signal with an SNR of 0 dB;
  • FIG. 7 shows the result of the correlation of the echo signal corresponding to FIG. 6 with the transmit signal according to FIG. 3;
  • FIG. 8 illustrates the triangulation method with three receivers for determining the spatial coordinates of a reflection point.
  • the generator 1 shows a device for 3D real-time sonography according to the invention in the form of a block diagram, in which an analog transmit signal is generated and the echo signals are consequently processed analog.
  • the generator 1 generates a carrier which is modulated in a modulator 2 with any function.
  • this transmission signal is emitted by a transmitter 3 into any medium or body.
  • the echo pulses reflected from the structures in the medium are received by the three receivers 4 in this exemplary embodiment.
  • each echo signal in correlator 5 must therefore first be correlated with the transmitted signal.
  • Each point of reflection in the medium is "seen" by the individual receivers 4 at a different time.
  • the modulator 2 is connected to the correlator 5 of each individual receiver 4.
  • the same features in the transmission signal and the respective echo signal mean a reflection Features can therefore be provided, for example, by shifting the transmission signal on the echo signals until there is a match which is an indication of a reflection to the point of reflection and back to the respective receiver 4. That is, the transmitter 3 and the respective receiver 4 lie in the two focal points of an ellipsoid.
  • the spatial coordinates of these reflection points are described in the following calculation Unit 6 determined by a simple triangulation.
  • the starting point is that the points of the same distance from the transmitter 3 to the reflection point and to the receiver 4 lie on an ellipsoid.
  • the intersection of the three ellipsoids indicates the spatial coordinates at which the actual reflection took place.
  • Fig. 8 illustrates this fact.
  • the spatial coordinates are then displayed on a display device 7 with the corresponding intensity.
  • the generator 1 generates a carrier which is modulated in a modulator 2 with any function.
  • the transmission signal is also emitted by a transmitter 3 into any medium.
  • an A / D converter 8 is arranged between the modulator 2 and each correlator 5 and each receiver 4 and the associated correlators 5.
  • a memory 9 is also arranged between the A / D converter 8 for the modulated signal and the generator 1 and stores the transmitted transmission signal for later repetition. For this purpose, the memory 9 is coupled to the generator 1.
  • FIG. 3 shows a transmission signal with an increasing frequency. It is a chirp with a frequency of f min to f max > The wavelength of this signal decreases from left to right in the drawing. The entire information content of the area of interest is recorded at the same time with only one transmission signal and processed in parallel in a fast computer.
  • the echo signals of the transmission signal described in FIG. 3 are received by each receiver 4. Such an echo signal, which was detected by one of the receivers 4 and which was reflected at three points, is shown in FIG. No noise components are superimposed on the echo signal in this representation. Only the first reflection point can be seen in this illustration. Additional reflection points are no longer recognizable in this diagram due to the superimposition of the echoes. Only after the correlation of the echo signal with the transmission signal do other reflection points become visible.
  • FIG. 5 shows the result of the correlation of the “chirp” according to FIG. 3 with the echo signal according to FIG. 4.
  • a pattern feature arises precisely at the reflection points, the amplitude of which is proportional to the quality of reflection or absorption.
  • the properties of the medium are of eminent importance. Because of its complicated composition, it is very difficult to derive a simple model that the Frequency dependence of the attenuation of the ultrasound describes. In general, a linear relationship between the attenuation, the distance traveled by the signal and the frequency is assumed. If G represents the attenuation (in dB), f the frequency (in MHz), z the depth (in cm) in the medium and ß the attenuation constant (in dB / [MHz cm]) of the medium, you get:
  • Gall bladder 0.5-1.0 fat 1.0-2.0
  • Table 2 shows the attenuation (in dB) as a function of the depth in the tissue and the frequency for tissue with the attenuation constant of 0.7 dB / [MHz cm]).
  • Point of reflection It is illustrated how it is possible to determine the spatial coordinates of reflection points by sending an arbitrarily modulated signal. After the distances of the reflection points from the respective transmitter 3 to the reflection points to the respective receiver 4 have been determined in the correlator, one can define ellipsoids in the focal points of which the transmitter 3 or the receiver 4 are arranged. Each intersection of all three ellipsoids characterizes the spatial coordinates of a reflection point. If there are more than three receivers for a transmitter, there are also more than three ellipsoids for each reflection point, all of which intersect at a point that determines the spatial coordinates of the respective reflection point. List of the reference symbols used

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Acoustics & Sound (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
  • Ultra Sonic Daignosis Equipment (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)

Abstract

L'invention concerne un procédé et un dispositif d'échographie 3D en temps réel. Le dispositif comprend une tête à ultrasons, une unité de traitement de signaux et un dispositif d'affichage. La tête à ultrasons comprend au moins un émetteur et au moins trois récepteurs, séparés dudit émetteur, dont la position par rapport à ce dernier est connue. L'unité de traitement de signaux comprend un générateur de signaux, qui génère un signal d'émission possédant n'importe quelle fonction de modulation; un corrélateur, connecté à chaque récepteur et relié au générateur de signaux; une unité de calcul, qui détermine les trajets du signal d'émission via la structure réfléchissante jusqu'aux récepteurs de chaque corrélateur; et une unité de calcul, qui détermine les coordonnées spatiales de la structure réfléchissante et à laquelle sont reliées toutes les unités de calcul déterminant lesdits trajets du signal d'émission.
EP00918814A 1999-04-07 2000-03-20 Procede et dispositif d'echographie 3d en temps reel Withdrawn EP1166148A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE1999115583 DE19915583A1 (de) 1999-04-07 1999-04-07 Vorrichtung und Verfahren für die 3D-Echtzeitsonographie
DE19915583 1999-04-07
PCT/EP2000/002436 WO2000062091A1 (fr) 1999-04-07 2000-03-20 Procede et dispositif d'echographie 3d en temps reel

Publications (1)

Publication Number Publication Date
EP1166148A1 true EP1166148A1 (fr) 2002-01-02

Family

ID=7903720

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00918814A Withdrawn EP1166148A1 (fr) 1999-04-07 2000-03-20 Procede et dispositif d'echographie 3d en temps reel

Country Status (6)

Country Link
EP (1) EP1166148A1 (fr)
JP (1) JP2002540910A (fr)
CN (1) CN1354834A (fr)
CA (1) CA2366534A1 (fr)
DE (1) DE19915583A1 (fr)
WO (1) WO2000062091A1 (fr)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10027828A1 (de) * 2000-06-05 2001-12-06 Sonem Gmbh Aktives Ultraschall-Sichtgerät
DE10112034A1 (de) * 2001-03-14 2002-10-02 Sonem Gmbh Anordnung zur Bildwiedergabe für Computertomographen mit Ultraschall
JP2008253663A (ja) * 2007-04-09 2008-10-23 Toshiba Corp 超音波診断装置およびその制御処理プログラム
CN101292883B (zh) 2007-04-23 2012-07-04 深圳迈瑞生物医疗电子股份有限公司 超声三维快速成像方法及其装置
US20160106392A1 (en) * 2013-05-24 2016-04-21 The Governing Council Of The University Of Toronto Ultrasonic array for bone sonography
JP7346249B2 (ja) * 2019-11-05 2023-09-19 株式会社ニチゾウテック 超音波探傷検査装置、および反射源特定方法
CN112326790B (zh) * 2020-10-28 2022-11-29 武汉中岩科技股份有限公司 一种超声波成孔检测探头装置及其检测方法
CN115604647B (zh) * 2022-11-28 2023-03-10 北京天图万境科技有限公司 一种超声波感知全景的方法及装置

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US5235857A (en) * 1986-05-02 1993-08-17 Forrest Anderson Real time 3D imaging device using filtered ellipsoidal backprojection with extended transmitters
US4855961A (en) * 1986-07-31 1989-08-08 Woods Hole Oceanographic Institute Imaging apparatus
US5111823A (en) * 1989-04-20 1992-05-12 National Fertility Institute Apparatus and method for generating echographic images
DE4331020A1 (de) * 1992-12-08 1994-06-09 Siemens Ag Ultraschall-Abbildungseinrichtung
US5842991A (en) * 1997-02-20 1998-12-01 Barabash; Leonid S. Ultrasound transducer with extended field of view
GB9714735D0 (en) * 1997-07-15 1997-11-05 Roke Manor Research Acoustic location system

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Title
See references of WO0062091A1 *

Also Published As

Publication number Publication date
CN1354834A (zh) 2002-06-19
JP2002540910A (ja) 2002-12-03
CA2366534A1 (fr) 2000-10-19
DE19915583A1 (de) 2000-10-12
WO2000062091A1 (fr) 2000-10-19

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