Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/56—Details of data transmission or power supply
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/44—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device
  • A61B8/4444—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device related to the probe
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
  • B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
  • B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
  • B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
  • B06B1/0207—Driving circuits
  • B06B1/0215—Driving circuits for generating pulses, e.g. bursts of oscillations, envelopes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
  • B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
  • B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
  • B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
  • B06B1/0207—Driving circuits
  • B06B1/0223—Driving circuits for generating signals continuous in time
  • B06B1/0238—Driving circuits for generating signals continuous in time of a single frequency, e.g. a sine-wave
  • B06B1/0246—Driving circuits for generating signals continuous in time of a single frequency, e.g. a sine-wave with a feedback signal
• • 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
  • G01S15/8909—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques using a static transducer configuration
  • G01S15/8915—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques using a static transducer configuration using a transducer array
• • 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
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
  • G01S7/52017—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00 particularly adapted to short-range imaging
  • G01S7/52019—Details of transmitters
  • G01S7/5202—Details of transmitters for pulse systems
• • 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
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
  • G01S7/52017—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00 particularly adapted to short-range imaging
  • G01S7/52096—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00 particularly adapted to short-range imaging related to power management, e.g. saving power or prolonging life of electronic components
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/52—Devices using data or image processing specially adapted for diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/5215—Devices using data or image processing specially adapted for diagnosis using ultrasonic, sonic or infrasonic waves involving processing of medical diagnostic data
  • A61B8/5223—Devices using data or image processing specially adapted for diagnosis using ultrasonic, sonic or infrasonic waves involving processing of medical diagnostic data for extracting a diagnostic or physiological parameter from medical diagnostic data
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
  • B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
  • B06B2201/00—Indexing scheme associated with B06B1/0207 for details covered by B06B1/0207 but not provided for in any of its subgroups
  • B06B2201/70—Specific application
  • B06B2201/76—Medical, dental

Definitions

• This invention relates to medical diagnostic ultrasonic imaging and, in particular, to powering ultrasonic transducer probes.
• Ultrasound transducer probes such as those used for 3D imaging, can have transmit circuitry located in the probe and coupled to the transducer array (sensor,) which excites the transducer elements with energy from power supplies located in ultrasound system.
• the front-end circuitry can require higher electrical currents than the system power supplies are capable of supplying. An attempt by a probe to draw these high currents can result in a decline of the voltage level of the high- voltage supply which provides drive voltage to the front-end and the transducer, which in turn results in a drop in the acoustic pressure of the transmitted ultrasound, which degrades imaging and therapeutic effect.
• the physical size of the capacitor bank is better
• the electrical resistance of the transducer cable becomes a constraining factor.
• the imaging modality can tolerate a 1 volt decline during a transmit pulse that requires 5A, the cable resistance needs to be less than 0.2 ⁇ .
• the present invention includes ultrasound imaging systems including an active supply provides power to the array transducer in an
• the ultrasound imaging systems can include an ultrasonic transducer located in a probe enclosure, an active supply, having an input coupled to a high voltage supply and an output coupled to the ultrasonic transducer, and a voltage feedback line coupled between the ultrasonic transducer and the active supply.
• the active supply can be configured to adjust an output voltage
• the active supply which supplies energy to the probe through conductors in the transducer cable, may be located a various places in the imaging system, such as in an ultrasound system mainframe, the transducer probe itself, or in the transducer probe's connector.
• the active high voltage supply can be coupled to a capacitor bank, which is charged to a higher voltage.
• the capacitor bank can be any suitable capacitor bank, which is charged to a higher voltage.
• the active supply receives feedback from a point closer to the sensor in the signal path and an error amplifier compares the feedback signal to a reference either generated on the connector or provided by the ultrasound system. In response to the error amplifier output, the active supply changes its output to compensate for the change in the load presented by the front end sensor.
• the capacitor bank stores enough charge for the active supply to provide the current needed by the sensor throughout the duration of the transmit excitation.
• the voltage of the capacitor bank can be high enough for the active supply to maintain the desired voltage at the transducer through the transmit interval.
• the use of the active supply allows use of the capacitor bank on the order of hundreds of microfarads instead of thousands as in the passive case, because its voltage decline can be many more volts than the voltage at the transducer front-end.
• FIGURE 1 is a schematic diagram of an ultrasound system constructed in accordance with the principles of the present invention.
• FIGURE 2 illustrates a probe with its cable and connector for an ultrasound system mainframe.
• FIGURES 3a and 3b illustrate schematic
• implementations of the present invention for positive and negative supply voltages.
• FIGURE 4 illustrates voltage and current levels during a transmit pulse at different points in an implementation of the present invention.
• FIGURE 5 is a schematic diagram of an active supply constructed in accordance with the principles of the present invention.
• FIGURE 6 is a block diagram of the supply of probe power using multiple active supplies.
• FIGURE 7 is a block diagram of another
• FIGURE 1 an ultrasound imaging system constructed in accordance with the principles of the present invention is shown in block diagram form.
• An ultrasound probe enclosure 10 is provided which is to be held by its handle section 8 with its distal end 6 against the body of a patient to image the anatomy below the point of contact.
• An array transducer inside the distal end 6 of the probe enclosure transmits focused pulses or waves along directions referred to as beam directions over a two or three dimensional region of the body. This region is shown as a sector-shaped plane 12 in FIGURE 1. Transmission is accomplished by applying high voltage pulses or waveforms to elements of the array
• transducer by transmitters located in the probe or an ultrasound system mainframe, to which the probe can be connected by a cable 24 or wirelessly. Echoes are returned from tissue, blood and structures along the beam directions in response to each transmission and the echoes are processed by beamforming with a system beamformer 14 to form coherent echo signals from the ultrasound signals received by elements of the array transducer. Some or all of the beamforming may also be performed by a microbeamformer ASIC located in the probe and coupled to the array transducer. After the received signals have been fully beamformed they are coupled to a signal processor 16 which performs functions such as decimation, filtering, harmonic separation, and signal compounding. The processed signals are coupled to an image processor 18 which forms them into images by processes such as amplitude or Doppler detection and scan conversion. The formed images are displayed on an image display 20.
• the system includes a power supply 22 which provides a number of voltages used to energize the various components of the ultrasound system.
• the power supply 22 can be coupled to an active supply 40 as described further herein and can provide a high voltage (e.g., ⁇ 100v) for use by the transmitter circuits to stimulate the transducer elements to transmit pulses or waves for imaging or therapy.
• the high voltage can be applied to transmitters in the system mainframe and/or transmitters in the probe 10.
• an ultrasound system mainframe is included in the system and is operable with a number of different types of probes for different diagnostic applications.
• the system mainframe can include one or more connectors to which probes may be connected.
• FIGURE 2 illustrates a probe 10 with a connector 30 at the proximal end of the cable 24. Strain reliefs 26 prevent excessive flexing at the ends of the cable where it is attached to the probe and probe connector. The probe
• connector 30 comprises a case which contains a multi- pin plug to which the conductors of the cable are connected.
• the plug is indicated at 36.
• the plug 36 is plugged into a mating connector on the ultrasound system and a lock handle 34 is turned to securely attach it to the system.
• an active supply 40 is used to provide a high voltage to the sensor as
• FIGURES 3a and 3b An active approach for supplying transmit energy can achieve the same supply voltage performance as the passive capacitor bank approach, but with less capacitance (e.g., about 90% less capacitance) and, as a result, a much smaller space requirement in the probe or system.
• an active supply and its capacitance can readily fit in several parts of an ultrasound system, including the probe, the system mainframe, and most conventional probe connectors.
• the active approach can use existing transducer cable designs.
• FIGURE 3a shows a simplified block diagram of an active supply for a transmitter in a transducer probe 10.
• the active supply 40 is located in the transducer connector 30 and supplies energy through conductors in the transducer cable 24.
• the active high voltage supply 40 is powered by a high voltage (+HV IN) from the power supply 22, which is applied to a capacitor CI at the input of the active supply.
• the power supply charges the capacitor CI to the high supply voltage.
• the capacitor CI can discharge by tens of volts during operation, but the active supply maintains the voltage at the probe's front end sensor 50 within a tighter range that is acceptable for imaging and therapy.
• the active supply receives feedback from the sensor along a voltage feedback line, and
• the active supply compares the feedback voltage in the circuitry to a reference voltage either generated in the connector 30 or provided by the ultrasound system mainframe.
• a reference voltage either generated in the connector 30 or provided by the ultrasound system mainframe.
• the active supply varies its output to compensate for the change in the load presented by the sensor.
• the capacitor CI stores enough charge for the active supply 40 to provide the current needed by the sensor 50 and its bypass capacitance 52 for the duration of the transmit excitation period.
• the voltage at the capacitor CI only needs to be high enough for the active supply to maintain the voltage at the sensor through the transmit interval.
• the capacitor CI can be on the order of hundreds of microfarads instead of thousands as in the passive case, because it can drop by many more volts than the actively controlled voltage at the sensor front-end.
• the active supply can provide either a positive or a negative high voltage and that the sensor load can source or sink current.
• a sensor may utilize one or both polarities of high voltage.
• FIGURE 3b schematically illustrates the same arrangement as FIGURE 3a but for a sensor requiring a negative (-HV) drive voltage.
• a negative high voltage is applied to the capacitor CI at the input to the active supply 40, and the current flow is in the opposite sense as indicated by the direction of the arrow in the symbol for the sensor 50.
• FIGURE 4 illustrates exemplary waveforms at points in the circuit of FIGURE 3b during the supply of a high negative transmit voltage.
• the input to the active supply 40 is -77V
• the voltage at the sensor 50 is maintained to within IV of -60V during a transmit interval of less than one millisecond, during which 5 amps (A) is drawn by the sensor.
• the capacitor CI has a value of 300 ⁇ and the voltage at the input to the active supply drops by 10V, from -77V to -67V as shown by curve 60.
• Negative feedback from the sense conductor of the cable 24 forces the active supply 40 to decrease the voltage at the connector end of the supply conductor of the cable 24 to compensate for the voltage drop over the cable when the sensor sinks 5A into the cable. This is shown by curve 62, where the nominal
• -60V is changed to -62.5V to account for the cable's voltage drop.
• Curve 64 shows the voltage change at the sensor, which is from -60V to -59V, an acceptable one volt decline, which occurs when the sensor is drawing 5A as shown by curve 66.
• the capability of sinking 5A at -60V during the transmit interval is something that the typical ultrasound system power supply cannot do with this performance.
• FIGURE 4 The active supply in this example is implemented as a high voltage linear regulator. It will be understood that switching supplies can also be used.
• the linear regulator as shown receives negative feedback from the sensor 50 at terminal FB, which enables it to maintain an approximately constant voltage at the feedback point, as the load and its input voltage vary. Since the high voltage supply -HV coupled to the input terminal IN of the linear regulator cannot sink 5A, the negative voltage on the capacitor CI will rise towards 0V during the load (transmit) interval .
• the regulator compensates for the change in load and its input voltage variation by varying the drain to source resistance of its NMOS pass transistor Ml.
• a feedback network consisting of resistors Rl and R2 sets the voltage to be produced for the supply conductor (s) at the output terminal OUT to be
• Transistors Ql and Q2 form an operational
• the current output of Ql drives the gate of the pass transistor Ml to a voltage which is set by resistor R4, thereby
• the voltage at the regulator output will decrease, which increases the bias of Q2 and results in an increase in the conductivity of Q2 and a decrease in the conductivity of Ql .
• This decreases the gate drive of the pass transistor which raises its drain-source resistance and increases the output voltage of the regulator.
• the same mechanism causes the drain- source resistance of the pass transistor Ml to decrease as the input voltage to the regulator decreases; and increase as the input voltage
• the linear regulator holds the voltage at a set voltage as the load and its input voltage vary.
• the discharge circuit protects the ultrasound system from being back-driven by capacitor CI when the negative high voltage supply is raised towards Ov.
• the discharge circuit also prevents a shock hazard which could occur if the capacitor CI were directly
• Diodes Dl and D2 become reverse-biased when -HV is increased by the system, or disconnected.
• the Q3 transistor then develops a positive bias on its base and drives the base of transistor Q4, which causes Q4 to discharge the capacitor CI through R7 and transistor Q4.
• an implementation of the present invention can employ multiple active supplies 40 and switches 44a, b, and c to change the actively
• FIGURE 6 shows the same circuitry for the transducer when the excitation voltage changes.
• FIGURE 6 shows the same circuitry for the transducer when the excitation voltage changes.
• the illustrated switching arrangement switches both the supply conductor and the sense line connections.
• the active supplies 40 are shown with a single capacitor CI.
• FIGURE 7 shows the same
• Switches 42a, b and c selectively couple the system high voltage HV to the capacitors CI .

Landscapes

• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Radar, Positioning & Navigation (AREA)
• Remote Sensing (AREA)
• Computer Networks & Wireless Communication (AREA)
• General Physics & Mathematics (AREA)
• Biomedical Technology (AREA)
• Molecular Biology (AREA)
• Pathology (AREA)
• Radiology & Medical Imaging (AREA)
• Biophysics (AREA)
• Heart & Thoracic Surgery (AREA)
• Medical Informatics (AREA)
• Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
• Surgery (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Acoustics & Sound (AREA)
• Mechanical Engineering (AREA)
• Ultra Sonic Daignosis Equipment (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=57326451

Family Applications (1)

Country Status (5)

Cited By (1)

Families Citing this family (4)

Citations (3)

Family Cites Families (44)

• 2016
  • 2016-11-02 JP JP2018522613A patent/JP7065768B6/ja active Active
  • 2016-11-02 EP EP16797651.3A patent/EP3370622B8/en active Active
  • 2016-11-02 WO PCT/IB2016/056582 patent/WO2017077456A1/en not_active Ceased
  • 2016-11-02 CN CN201680063983.0A patent/CN108472007B/zh active Active
  • 2016-11-02 US US15/768,989 patent/US10799220B2/en active Active

Patent Citations (3)

Also Published As

Similar Documents

Legal Events