This standard specifies the acoustic field characteristics and measurement methods of medical extracorporeal pressure pulse lithotripsy. The measured parameters can be used to announce the acoustic output of such equipment. This standard applies to medical lithotripsy that introduces pressure waves from outside the body and focuses mechanical energy, but does not apply to percutaneous lithotripsy and laser lithotripsy. GB/T 16407-2006 Acoustics Acoustic field characteristics and measurement of medical extracorporeal pressure pulse lithotripsy GB/T16407-2006 Standard download decompression password: www.bzxz.net
This standard specifies the acoustic field characteristics and measurement methods of medical extracorporeal pressure pulse lithotripsy. The measured parameters can be used to announce the acoustic output of such equipment. This standard applies to medical lithotripsy that introduces pressure waves from outside the body and focuses mechanical energy, but does not apply to percutaneous lithotripsy and laser lithotripsy.

ICS t7, 140
National Standard of the People's Republic of China
GB/T16407-2006/IEC 61846:1998
Acoustics-Characteristics and measurementsof field of pressure pukse lithotripters (IEC61846:1998 Ultrasonics-Pressure pulse lithotripters:-Characteristies of fields, 1DT2006-07-25Promulgated
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Administration of Standardization of the People's Republic of China
2006-12-01Implementation
GB/T 16407—2006/IEC61846;1998 Foreword
Normative references
Terms and definitions
Measurement conditions
Measurement equipment
Water tank
Hydrophone
Voltage measurement
Measurement procedure
7.1 Measurement in the time domain
7.2 Measurement in the time domain
7.3 Acoustic energy measurement
Appendix A (informative)
Appendix B (informative)
Appendix C (informative)
Appendix D (informative)
Acoustic lithotripsy technique
Types of pressure transducers
Sound field measurement
References
GB/T 16407--2006/1EC 61846:1998 This standard is equivalent to EC6184G1998% ultrasonic medical pressure pulse lithotripsy acoustic field characteristics and has been edited and revised. This standard is a revision of GB/T16407-1996, and the requirements for hydrophones and related appendices are added in the revision. Appendix A, Appendix B, Appendix C and Appendix D of this standard are informative appendices. This standard was proposed by the Chinese Academy of Sciences.
This standard was developed by the National Acoustic Standardization Technical Committee (SAC/TC1?). The originating unit of this standard: Acoustic Standardization Technical Committee of the Chinese Academy of Sciences Institute of Medicine, Shanghai Jiaotong University, National Medical Ultrasonic Equipment Testing Center, Peking University People's Hospital Institute of Ultrasonics.
The main drafters of this standard are Mi Houqing, Mo Xiping, Shou Wende, Wang Zhijian, and He Chuancheng. The previous versions of the standard represented by this standard are: GB/Tt6407-1996.
GB/T16407--2006/IEC61846:1998 Introduction
Extracorporeal lithotripsy is used in the clinical treatment of kidney stones, bladder stones, and gallstones. The high-intensity sound waves generated by the lithotripsy crush the stones through a series of sound waves. At present, there are different types of crushers produced by some manufacturers on the market. This standard describes the characteristics of the sound field generated by the extracorporeal lithotripsy and specifies the corresponding measurement methods. 1 Scope
GB/T16407—2006/IEC61846:199E Acoustics Acoustic field characteristics and measurement methods of medical extracorporeal pressure pulse lithotripsy
This standard specifies the acoustic field characteristics and measurement methods of medical extracorporeal pressure pulse lithotripsy. The measured parameters can be used to publish the acoustic output of such equipment.
This standard applies to medical lithotripsy equipment that introduces pressure waves and focuses mechanical energy from outside the body, but does not apply to percutaneous lithotripsy equipment and laser lithotripsy equipment.
Note: At present, the parameters defined in this standard cannot be used as a definite regulation of the effectiveness and possible harm of the lithotripsy, especially it cannot be used to make restrictive regulations on these effects.
This standard is formulated for extracorporeal lithotripsy. In other medical applications of therapeutic extracorporeal pressure pulses, this standard can also be used as a guide as long as no other specific valid standards are involved. 2 Normative references
The clauses in the following documents become the clauses of this standard through reference in this standard. For all dated references, all subsequent amendments (excluding errata) or revisions are not applicable to this standard. However, parties to agreements based on this standard are encouraged to study whether the latest versions of these documents can be used. For all undated references, the latest versions apply to this standard. GB/T 3947-1996 Technical terms and terms
GB/T 16540-1996 Ultrasonic field characteristics and their measurement in the frequency range of 0.5 to 15 MHz Hydrophone method (IEC 61102: 1991)
IEC 60866: 1987 Characteristics and calibration of hydrophones in the frequency range of 0.5 to 15 MHz 3 Terms and definitions
GB/T 3947-1996 and the following terms and definitions are applicable to this standard. 3.1
Medical lithotripsy equipment Lithotripsy equipment is used to crush stones and other contaminants in the human body. Previous: Medical stone removal equipment can be used for the clinical treatment of kidney stones, gallstones, duct stones, glandular stones, joint pain and muscle calcification. 3.2
Hydrophone (underwater microphone) bydrophone (underwater microphooe) is an electroacoustic transducer used to receive water signal. Previous: Due to different working principles, characteristics and structures, there are sound pressure, sound pressure gradient, directional, pointing, piezoelectric fiber and other hydrophones. 3.3
End-uf-cable Joaded sensitivity of a hylrophone14
When the hydrophone is connected to a load with a specified input impedance, the ratio of the output voltage at the end of its cable or connector to the instantaneous sound pressure of the plane wave free field at the acoustic center of the hydrophone when the hydrophone is moved, the unit is volt per Pascal (V/P:). 3.4
Sound pressure
GB/T 16407-2006/IEC61846:1998 The difference between the force and static pressure in the medium, in Pascal (Pa). 3.5
Sound intensity(sound energy flux density, sound power density)1
At a certain moment: at a certain point in the sound field, the sound energy passing through a unit area perpendicular to the direction of the particle velocity in a unit time is called instantaneous sound intensity. In a steady-state sound field, the sound intensity is the average value of the instantaneous sound intensity in a certain time. The unit is watt per square meter (W/㎡). [See 2.26J in CB/T3947.
Pressure pulsepressure pulse
Sound pressure pulse of dust produced by medical lithotripsy
Sound pressure pulse waveformpressure pulse waveformThe time waveform of the instantaneous sound pressure at a specified position in the pressure pulse sound field that contains all sufficient information. 3.8
Pulse sound pressure square integralpulse-pressure-squarel integral;
The time integral of the square of the instantaneous sound pressure on the sound pulse waveform, in units of quadratic Pascal-seconds (Pa·s). 3.9
Derived pulse-intensity integralFH
In the pressure pulse sound field, the integral of the instantaneous sound intensity at a point over the duration of the entire pulse waveform, in units of joules per square meter (J/). 3. 10
derived acoustic pulse energyER
derived acoustic pulse intensity integral is the spatial integral of the cross-sectional area with radius R in the plane perpendicular to the beam axis and including the focus. The unit is joule (J).
derived focal acoustic pulse energyderived facal acoustic pulse energyE
derived acoustic pulse intensity integral is the spatial integral of the cross-sectional area of ​​the focus. The unit is joule (I). 3. 12
peak-positive acoustic pressure, peak-compressional acoustic pressure+
the maximum compressive pressure at any position in the acoustic pulse field. The unit is Pascal (Pa). 3.13
Negative acoustic pressure peak valuepeak-negativeacoustic pressure, peak-rarefractionulacousticpressurep
The maximum absolute value of the rarefied acoustic pressure at any position in the pressure pulse sound field. The unit is Pascals (Pa). 3. 14
Positive acoustic pressure [compression] pulse width
compressional palse durationtywHp
The time difference between the two instantaneous pressures before and after the peak value of the positive acoustic pulse, when the sound pressure value is equal to 50% of the pulse peak value, in seconds (s). Note: The subscript FWHM represents full width half maximum. 2
Negative sound pressure pulse width Rare negative acoustic pulse width WHM
GB/T16407—2006/IEC61846:1998 The time difference between the two instantaneous sound pressures before and after the peak value of a negative acoustic pulse, when the pressure value is equal to 50% of the peak value of the negative pulse, in seconds (s): 3.16
Positive temporal Integratlon limits The time from the time when the positive pulse sound pressure exceeds 10% of the maximum value for the first time to the time when it decreases to 10% of the maximum value for the first time, in seconds (s). 3.17
total termporal integratlon limits The time from the time when the absolute value of the sound pressure pulse waveform exceeds 10% of the maximum value for the first time to the time when it decreases to 10% of the maximum value for the last time, in seconds (s).
Rise time
The time taken for the leading edge of the positive sound pressure pulse at the focus to rise from 10% to 90% of the peak pressure, in seconds (s). 3.19
Focus
The position of the maximum positive sound pressure peak in the pressure pulse sound field. 3.20
Beam axis
The straight line through the geometric center of the pressure pulse generator aperture and the focus. 3.21
Focal length
focalextent
The shortest distance on either side of a point on the beam axis that is 6 dB lower than the maximum positive sound pressure peak, in meters (m). 3.22
maximum focal width
Maximum focal width
The maximum width of the equal sound pressure lines around the focus that are 6 lower than the maximum positive sound pressure peak in the plane containing the focus, in meters (m).
Orthogonal focal width is the width of the equal sound pressure lines around the focus that are 6 lower than the maximum positive sound pressure peak in the plane containing the focus, in meters (m).
Focal cross-sectinnal areaAr
The area of ​​the region enclosed by the equal sound pressure lines 6 dB lower than the maximum positive sound pressure peak (0 dB) in the plane perpendicular to the axis of the sound beam at the focal point. The unit is square meter (m)
GB/T16407-2006/IEC61846:19983.25
Focal volume
focal yolume
The area enclosed by the interface 6 dR lower than the maximum positive sound pressure peak (0 dR) around the focal point, the unit is cubic meter (n). Note: The 6 dB isosonic region around the focus is difficult to measure: in practice, the maximum beam diameter in two orthogonal directions, namely the beam axis (≥ axis), the working axis and the axis perpendicular to the axis, is approximately 3.26
target (target area) position
target lncation
The spatial position of the stone is determined by the lithotripter manufacturer for the user. 4 Symbols
Ar——focal cross-sectional area, m2;
derived focal spot acoustic pulse energy J:
derived pulse acoustic energy, J
f——focal width in the force direction, m
f, focal width in the negative direction, m;
f. focal length·mt
instantaneous sound intensity, W/m;
water acoustic cable end load sensitivity, V/Pa section sound pressure, Pa;
negative peak sound pressure, Pa;
p_positive peak sound pressure, Pa
trwHMp+
tewHVA
5 Measurement conditions
-Square integral of pulse sound pressure. Pa·st
Derived pulse sound intensity integral, J/m\
Rise time, s:
End compression pulse width, s:
Negative compression pulse width, s;
Positive time integral limit, s1
Total time integral limit, 5!
Focal column volume, m\:
-Characteristic acoustic impedance of the medium, Pa·s/rn: The measurement should be carried out under conditions close to clinical use. The following parameters should also be recorded: driving voltage value of pressure pulse generator;
Pressure pulse release rate:
Ambient temperature,
Measurement water conductivity in the water tank;
Measurement water temperature and oxygen content in the water tank.
The measurement water tank should be large enough to meet the oxygen measurement conditions close to the self-exiting field. Deaerated water at 20°C to 40°C is preferred (see Appendix C). If deaerated water is not used, special care should be taken to ensure that no bubbles accumulate on the hydrophone and in the sound path. The conductivity of the water should be compatible with the hydrophone used. The sensitivity of the hydrophone should be based on the calibration data at the water temperature of the water tank. 4
6 Measuring equipment
6.1 Measuring water tank
GB/T16407-2006/1EC61846:1998 The measuring water tank should be firmly mounted on the pressure pulse generator and well coupled with the water medium to ensure good transmission of the pressure pulse energy. The water column should be large enough to ensure that the focal area is several centimeters away from the reflection boundary, paying special attention to the distance from the water surface to the focal area and the reflection interface, so that multiple reflections of the sound pulse do not disturb the measurement: the hydrophone should have an appropriate mechanical support and be placed on a coordinate positioning system so that the measurement position of the hydrophone can be adjusted in three directions relative to the focus. The precise positioning of the hydrophone at the focal position is very important. One axis (axis) of the positioning coordinate system is coaxial with the axis of the sound beam. The positioning accuracy of the hydrophone is not less than 0.5 mm. Care should be taken to ensure that the coupling film does not affect the measurement. The coupling agent used should be specified by the manufacturer. 6.2 Hydrophones
The characteristics of the hydrophone used for measurement shall comply with the provisions of IEC60866:1987. This standard specifies the use of two types of hydrophones:
—Focal hydrophone;
—Sound field hydrophone,
6.2.1 Point hydrophone
The focal hydrophone can be a piezoelectric film point polarization hydrophone with a film thickness of no more than 25μm (see Appendix C and GB/T165401996). Calibration should be performed in the frequency range of 0.5MJI2~15MH2 according to IEC60866:1987. The unevenness of the frequency response shall not exceed +3dB within the calibrated frequency range. The effective diameter of the hydrophone shall not exceed 1.0mm and shall be as small as possible. The diameter value shall be published. Note: According to IEC60866, 1987 and GJ/T165401996, the low frequency limit of hydrophone calibration is 0.5 MHz. However, for the above measurement, it is best to reduce the calibration frequency to at least 0.2 MHz. 6.2.2 Sound field hydrophone
The sound field hydrophone should have a structure that is not easy to break, and the frequency response non-uniformity in the frequency range of 0.5 MHz to 15 MHz should not exceed 23 dB per octave. The effective diameter of the hydrophone is not more than 1.0 mm and as small as possible. The diameter value should be published. During the measurement process, the sensitivity value of the hydrophone should not change by more than ±10%. Note: It is allowed to use two different types of hydrophones, because most hydrophones are very easy to break at the focus. Therefore, a hydrophone with a higher sensitivity but less easy to break can be used as a general sound field measurement hydrophone. As a sound field measurement, the hydrophone must also be able to ensure the output of linear and negative pulse sound pressure at high sound pressure.
6.3 Voltage measurement
6.3.1 Storage oscilloscope or transient recorder Although transient recorders, digital storage and computer display can meet the requirements, it is recommended to use digital storage oscilloscopes first. The sampling frequency of the digital storage oscilloscope is greater than 100MHz. The frequency response, input resistance and parallel capacitance of the oscilloscope are given. The load sensitivity of the hydrophone winding end is calculated according to 5.1.2 of GR/T16540-1996, and then this value should be used to calculate the incident sound pressure from the output voltage of the measured hydrophone. 6.3.2 Pressure pulse glass recording
According to the output voltage waveform of the recorded hydrophone, the following parameters can be measured and calculated: instantaneous sound intensity
-negative peak sound pressure
-positive peak sound pressure
-rise time t.;
-constricted pulse width tEEHMP
-instantaneous sound intensity l.
GB/T16407-2006/[EC61846:19987 Setting procedure
The measurement should be carried out under at least one clinical setting condition specified by the manufacturer. If one setting condition is used, the setting should be able to produce the maximum effective output in clinical applications, and the setting condition should be stated. Use the y-coordinate system, and the axis direction is the beam axis direction. The following measurements can give the spatial characteristics of the beam. The axis is defined as the direction of the maximum beam width on a fixed plane including the focus. The distance between the focus and the target position should be noted. If the difference between the positive peak sound pressure at the target position and the focus is not greater than 10%, the measurement can be carried out in the ! plane at the target position 2 flexibly.
7. 1 Spatial measurement
The spatial distribution of the sound pressure should be measured in the measuring tank. The maximum spatial sampling interval in the 2:3r plane is 1 mm or 1/2 of the minimum width of the -6 dB isobar, whichever is smaller, and in the ? plane is 2 mm or 1/2 of the maximum dimension of the 6 dB isobar, whichever is smaller. If the difference between the sampling points is not greater than 10%, the spacing between the sampling points can be extended to 5 mm or 10 mm. Field hydrophones can be used. The spacing between the sampling points should be stated when giving the spatial distribution. Note 1: Before making other measurements, first make a measurement near the reference point to determine the focal position (see Appendix 3). Note: The focal position can only be determined accurately after the measurement in 7.1.1 is completed. Note 3: The hydrophone must be carefully selected to have sufficient linearity in the positive and negative pulse regions to ensure that no deviation occurs during the measurement. 7.1.1 Positive Peak Sound Pressure Beam Pattern
The measurement includes the peak pressure in the xy plane at the focal point, and the -6dB beam width is determined by the -6dB isobars. The direction of the maximum beam width in the -y plane is selected and the -6dB isobars in the -z plane and the -z plane are measured. The positive sound pressure at each point in the axial direction can be calculated to obtain the pulse sound intensity integral (see 7.3.1). Because the two curves are different, the areas calculated by the two curves will be quite different. 7.1.2 Negative peak sound pressure beam diagram
Measure the negative peak sound pressure on the surface of & and 2, and estimate the amplitude and position of the maximum negative sound pressure value. In fact, these measurements are difficult, so the spatial sampling interval can be flexibly selected. If the difference in P_values ​​at each point does not exceed 10%, the sampling interval can be specified.
7.1.3 Focus point
The distance between the focal point and the moon mark should be determined, and its accuracy should be within ±2 mm in the axial direction and within ±3 mm in the axial direction.
7.1.4 Focal area width
According to the measurement in 7.1.1, the maximum focal area width f1 on the isoacoustic pressure line of 6dI3 in the y direction can be obtained. The focal area width f2 can be obtained in the orthogonal direction.
7.1.5 Focal area length
According to the isoacoustic pressure diagram of 6 dB on the surface in 7.1.1, the focal area length f2 between the isoacoustic lines of 6dI3 in the y direction can be obtained.
7.1.6 Focal area area
According to the spatial distribution, the focal area transverse area along the y-axis and the y-axis can be determined. Note: The focal area can be approximated as the area of ​​the circular surface with the axial lengths of t1, t2 and t3, respectively. 7.1.7 Focal volume
Based on the spatial distribution, the focal volume along the , and y axes can be obtained. Note: The focal volume can be approximated as a sphere with axis lengths of , , and y, respectively. 7.2 Time domain measurement
The focal hydrophone is placed at the focal position, and the difference between the measured positive peak sound pressure and the one given in the manual shall not exceed ±20. The pressure pulse waveform is measured at the point, and the following parameters are obtained: 6
Positive peak pressure and negative peak pressure:
Pulse width;
—Rise time.
7. 3 Acoustic energy measurement
7.3.1 Square integral of pulse sound pressure
The square integral of the pulse sound pressure at any point (r, y) is as follows: pi(r)=
Note: The integration limit T can be T, or T+.
7.3.2 Derived pulse intensity integral
The derived pulse intensity integral of any point (r, is as shown in formula (2)PI (r.6)
Where:
is the characteristic acoustic impedance of water (see Appendix C). Note: The integration is performed in the time domain, T can be T, or TT. The measurement should be made using a focal hydrophone.
7.3.3 Derived focal acoustic pulse energy
a\(r,et)dt
GH/T 16407—2006/IEC61846:19981
(r.8,n)de
The focal acoustic pulse energy can be calculated from the derived pulse intensity integral focal domain transverse surface integral, as shown in formula (3): E
Note: The integration limit can be T, or T,
where,
P(r.,r)dsdt -
1 I (r,8)ds
p(r,0,t)——the sound pressure at any point (r,8) in time: S——the area within the 6dB equal pressure line passing through the focus and perpendicular to the beam axis (polar coordinates, spatial coordinates): z-
——the characteristic acoustic impedance of water (see Appendix C). 7, 3, 4 Derived acoustic pulse energy
The acoustic pulse energy can be derived from the integral calculation of the Lu strength in the cross-sectional area S with a radius of R, as shown in formula (4): ER =
p*(r,8,tdsd =
The R value is specified and the size of the stone can be simulated. P (r,gds ..
（2）
GB/T16407--2006/IEC61846:1998A. 1 Background
Appendix A
(Informative Appendix)
Ultraperitoneal lithotripsy
In many countries, kidney stones and ureteral stones are common. In Europe, the incidence is estimated to be 3% to 4% of the population. This figure does not include the common gallstones.
The usual treatment for kidney stones, ureteral stones and gallstones is invasive surgery, which requires the patient to stay in the hospital for 1 to 3 weeks and has a long recovery period. Since 1978, two new treatment methods, percutaneous ultrasonic lithotripsy and extracorporeal ultrasonic lithotripsy, have become increasingly important. Currently, there are more than 10,000 surgical procedures on the market. Clinical stone treatment, this method can not only reduce trauma, but is even non-invasive, which can shorten the hospitalization and postoperative recovery time. Both methods use high-intensity focused sound waves to break up the stones. The earliest ultrasound equipment using this method used a continuous wave sound source in direct contact with the patient. Extracorporeal lithotripsy uses sequence pulse pressure waves. Percutaneous laser lithotripsy is also valued due to its low surgical trauma. Since the 1990s, a large number of literatures have shown that the potential of high-intensity ultrasound in the treatment of diseases such as bone and joint pain, fracture recovery and muscle calcification has attracted more and more attention. A.2 Percutaneous continuous wave system
Using ultrasound The idea of ​​using acoustic energy to break up stones was first seen in 1953, but actual work was not reported until the 1970s. Although such equipment is still in production, it has not been widely adopted because the treatment time is too long. A.3 Limitations
This section does not discuss percutaneous continuous wave systems and semi-invasive laser lithotripsy. Although laser lithotripsy can combine local plasma and shock waves, this section only considers extracorporeal pressure pulse methods and equipment. A.4 Extracorporeal lithotripsy
Despite the high cost of extracorporeal lithotripsy, the clinical application of extracorporeal lithotripsy for breaking up stones has developed rapidly. In Germany, due to the high cost of this method It is non-invasive, has a short treatment time and a fast recovery, and is now very common in clinical practice. Different models of extracorporeal lithotripters can be purchased from different manufacturers. The key factor in clinical practice is to accurately determine the location of the stone and the location of the stone by the transducer focal column volume. This can be done by three-dimensional positioning using X-rays and B-ultrasound diagnosis, and the process of stone crushing can be monitored in real time using B-ultrasound. The duration of clinical treatment varies and mainly depends on the extracorporeal lithotripter system and the shape, location and size of the stone. The crushed kidney stone fragments are discharged through the ureter, bladder and urethra in the following days. For guanidinium stones, due to the special location of the stone and the softness of the stone, excretion is somewhat difficult.;
--·Condensed pulse width tEEHMP
--Instantaneous sound intensity 1.
GB/T16407-2006/[EC61846:19987 Setup procedure
The measurement should be carried out under at least one clinical setting condition specified by the manufacturer. If one setting condition is used, the setting should produce the maximum effective output in clinical application, and the setting condition should be stated. Using the y-coordinate system, the direction of the axis is the beam axis direction. The following measurements can give the spatial characteristics of the beam. The axis is defined as the direction of the maximum beam width in a plane including the focus. The distance between the focus and the target position should be noted. If the difference between the positive peak sound pressure at the target position and the focus is not greater than 10 degrees, the measurement can be flexibly carried out in the plane at the target position 2!
7.1 Spatial measurements
The spatial distribution of the sound pressure should be measured in the measuring trough. The maximum spatial sampling interval in the 2:3r plane is 1 mm or 1/2 of the minimum width of the -6 dB isobar, whichever is smaller. In the - plane it is 2 mm or 1/2 of the maximum dimension of the 6 dB isobar, whichever is smaller. If the difference in the sampling points is less than 10%, the interval between the sampling points may be increased to 5 mm or 10 mm. Field hydrophones may be used. The interval between the sampling points should be stated when the spatial distribution is given. Note 1: Before making other measurements, first make a measurement near the reference point to determine the focal position (see Appendix 3). Note: Only after the measurements in 7.1.1 have been completed can the exact determination of the focal position be made. Note 3: The hydrophone must be carefully selected to have sufficient linearity in the positive and negative pulse regions to ensure that no deviations occur during the measurement. 7.1.1 Positive Peak Sound Pressure Beam Diagram
Measure the peak sound pressure in the xy plane including the focal point, and determine the -6dB beam width from the -6dB isobars. Select the direction of the maximum beam width in the -y plane and measure the -6dB isobars in the -z plane and the -z plane. The positive sound pressure at each point in the axial direction can be calculated to obtain the pulse intensity integral (see 7.3.1). Since the two curves are different, the calculated areas of the two curves will be quite different. 7.1.2 Negative Peak Sound Pressure Beam Diagram
Measure the negative peak sound pressure in the xy plane and the -6dB beam width, and estimate the amplitude and position of the maximum negative sound pressure value. In fact, these measurements are relatively difficult, so the spatial sampling interval can be flexibly selected. If the difference in P_values ​​at each point does not exceed 10%, the sampling interval can be specified.
7.1.3 Focus point
The distance between the focal point and the moon mark should be determined, and its accuracy should be within ±2 mm in the axial direction and within ±3 mm in the axial direction.
7.1.4 Focal area width
According to the measurement in 7.1.1, the maximum focal area width f1 on the isoacoustic pressure line of 6dI3 in the y direction can be obtained. The focal area width f2 can be obtained in the orthogonal direction.
7.1.5 Focal area length
According to the isoacoustic pressure diagram of 6 dB on the surface in 7.1.1, the focal area length f2 between the isoacoustic lines of 6dI3 in the y direction can be obtained.
7.1.6 Focal area area
According to the spatial distribution, the focal area transverse area along the y-axis and the y-axis can be determined. Note: The focal area can be approximated as the area of ​​the circular surface with the axial lengths of t1, t2 and t3, respectively. 7.1.7 Focal volume
Based on the spatial distribution, the focal volume along the , and y axes can be obtained. Note: The focal volume can be approximated as a sphere with axis lengths of , , and y, respectively. 7.2 Time domain measurement bzxZ.net
The focal hydrophone is placed at the focal position, and the difference between the measured positive peak sound pressure and the one given in the manual shall not exceed ±20. The pressure pulse waveform is measured at the point, and the following parameters are obtained: 6
Positive peak pressure and negative peak pressure:
Pulse width;
—Rise time.
7. 3 Acoustic energy measurement
7.3.1 Square integral of pulse sound pressure
The square integral of the pulse sound pressure at any point (r, y) is as follows: pi(r)=
Note: The integration limit T can be T, or T+.
7.3.2 Derived pulse intensity integral
The derived pulse intensity integral of any point (r, is as shown in formula (2)PI (r.6)
Where:
is the characteristic acoustic impedance of water (see Appendix C). Note: The integration is performed in the time domain, T can be T, or TT. The measurement should be made using a focal hydrophone.
7.3.3 Derived focal acoustic pulse energy
a\(r,et)dt
GH/T 16407—2006/IEC61846:19981
(r.8,n)de
The focal acoustic pulse energy can be calculated from the derived pulse intensity integral focal domain transverse surface integral, as shown in formula (3): E
Note: The integration limit can be T, or T,
where,
P(r.,r)dsdt -
1 I (r,8)ds
p(r,0,t)——the sound pressure at any point (r,8) in time: S——the area within the 6dB equal pressure line passing through the focus and perpendicular to the beam axis (polar coordinates, spatial coordinates): z-
——the characteristic acoustic impedance of water (see Appendix C). 7, 3, 4 Derived acoustic pulse energy
The acoustic pulse energy can be derived from the integral calculation of the Lu strength in the cross-sectional area S with a radius of R, as shown in formula (4): ER =
p*(r,8,tdsd =
The R value is specified and the size of the stone can be simulated. P (r,gds ..
（2）
GB/T16407--2006/IEC61846:1998A. 1 Background
Appendix A
(Informative Appendix)
Ultraperitoneal lithotripsy
In many countries, kidney stones and ureteral stones are common. In Europe, the incidence is estimated to be 3% to 4% of the population. This figure does not include the common gallstones.
The usual treatment for kidney stones, ureteral stones and gallstones is invasive surgery, which requires the patient to stay in the hospital for 1 to 3 weeks and has a long recovery period. Since 1978, two new treatment methods, percutaneous ultrasonic lithotripsy and extracorporeal ultrasonic lithotripsy, have become increasingly important. Currently, there are more than 10,000 surgical procedures on the market. Clinical stone treatment, this method can not only reduce trauma, but is even non-invasive, which can shorten the hospitalization and postoperative recovery time. Both methods use high-intensity focused sound waves to break up the stones. The earliest ultrasound equipment using this method used a continuous wave sound source in direct contact with the patient. Extracorporeal lithotripsy uses sequence pulse pressure waves. Percutaneous laser lithotripsy is also valued due to its low surgical trauma. Since the 1990s, a large number of literatures have shown that the potential of high-intensity ultrasound in the treatment of diseases such as bone and joint pain, fracture recovery and muscle calcification has attracted more and more attention. A.2 Percutaneous continuous wave system
Using ultrasound The idea of ​​using acoustic energy to break up stones was first seen in 1953, but actual work was not reported until the 1970s. Although such equipment is still in production, it has not been widely adopted because the treatment time is too long. A.3 Limitations
This section does not discuss percutaneous continuous wave systems and semi-invasive laser lithotripsy. Although laser lithotripsy can combine local plasma and shock waves, this section only considers extracorporeal pressure pulse methods and equipment. A.4 Extracorporeal lithotripsy
Despite the high cost of extracorporeal lithotripsy, the clinical application of extracorporeal lithotripsy for breaking up stones has developed rapidly. In Germany, due to the high cost of this method It is non-invasive, has a short treatment time and a fast recovery, and is now very common in clinical practice. Different models of extracorporeal lithotripters can be purchased from different manufacturers. The key factor in clinical practice is to accurately determine the location of the stone and the location of the stone by the transducer focal column volume. This can be done by three-dimensional positioning using X-rays and B-ultrasound diagnosis, and the process of stone crushing can be monitored in real time using B-ultrasound. The duration of clinical treatment varies and mainly depends on the extracorporeal lithotripter system and the shape, location and size of the stone. The crushed kidney stone fragments are discharged through the ureter, bladder and urethra in the following days. For guanidinium stones, due to the special location of the stone and the softness of the stone, excretion is somewhat difficult.;
--·Condensed pulse width tEEHMP
--Instantaneous sound intensity 1.
GB/T16407-2006/[EC61846:19987 Setup procedure
The measurement should be carried out under at least one clinical setting condition specified by the manufacturer. If one setting condition is used, the setting should produce the maximum effective output in clinical application, and the setting condition should be stated. Using the y-coordinate system, the direction of the axis is the beam axis direction. The following measurements can give the spatial characteristics of the beam. The axis is defined as the direction of the maximum beam width in a plane including the focus. The distance between the focus and the target position should be noted. If the difference between the positive peak sound pressure at the target position and the focus is not greater than 10 degrees, the measurement can be flexibly carried out in the plane at the target position 2!
7.1 Spatial measurements
The spatial distribution of the sound pressure should be measured in the measuring trough. The maximum spatial sampling interval in the 2:3r plane is 1 mm or 1/2 of the minimum width of the -6 dB isobar, whichever is smaller. In the - plane it is 2 mm or 1/2 of the maximum dimension of the 6 dB isobar, whichever is smaller. If the difference in the sampling points is less than 10%, the interval between the sampling points may be increased to 5 mm or 10 mm. Field hydrophones may be used. The interval between the sampling points should be stated when the spatial distribution is given. Note 1: Before making other measurements, first make a measurement near the reference point to determine the focal position (see Appendix 3). Note: Only after the measurements in 7.1.1 have been completed can the exact determination of the focal position be made. Note 3: The hydrophone must be carefully selected to have sufficient linearity in the positive and negative pulse regions to ensure that no deviations occur during the measurement. 7.1.1 Positive Peak Sound Pressure Beam Diagram
Measure the peak sound pressure in the xy plane including the focal point, and determine the -6dB beam width from the -6dB isobars. Select the direction of the maximum beam width in the -y plane and measure the -6dB isobars in the -z plane and the -z plane. The positive sound pressure at each point in the axial direction can be calculated to obtain the pulse intensity integral (see 7.3.1). Since the two curves are different, the calculated areas of the two curves will be quite different. 7.1.2 Negative Peak Sound Pressure Beam Diagram
Measure the negative peak sound pressure in the xy plane and the -6dB beam width, and estimate the amplitude and position of the maximum negative sound pressure value. In fact, these measurements are relatively difficult, so the spatial sampling interval can be flexibly selected. If the difference in P_values ​​at each point does not exceed 10%, the sampling interval can be specified.
7.1.3 Focus point
The distance between the focal point and the moon mark should be determined, and its accuracy should be within ±2 mm in the axial direction and within ±3 mm in the axial direction.
7.1.4 Focal area width
According to the measurement in 7.1.1, the maximum focal area width f1 on the isoacoustic pressure line of 6dI3 in the y direction can be obtained. The focal area width f2 can be obtained in the orthogonal direction.
7.1.5 Focal area length
According to the isoacoustic pressure diagram of 6 dB on the surface in 7.1.1, the focal area length f2 between the isoacoustic lines of 6dI3 in the y direction can be obtained.
7.1.6 Focal area area
According to the spatial distribution, the focal area transverse area along the y-axis and the y-axis can be determined. Note: The focal area can be approximated as the area of ​​the circular surface with the axial lengths of t1, t2 and t3, respectively. 7.1.7 Focal volume
Based on the spatial distribution, the focal volume along the , and y axes can be obtained. Note: The focal volume can be approximated as a sphere with axis lengths of , , and y, respectively. 7.2 Time domain measurement
The focal hydrophone is placed at the focal position, and the difference between the measured positive peak sound pressure and the one given in the manual shall not exceed ±20. The pressure pulse waveform is measured at the point, and the following parameters are obtained: 6
Positive peak pressure and negative peak pressure:
Pulse width;
—Rise time.
7. 3 Acoustic energy measurement
7.3.1 Square integral of pulse sound pressure
The square integral of the pulse sound pressure at any point (r, y) is as follows: pi(r)=
Note: The integration limit T can be T, or T+.
7.3.2 Derived pulse intensity integral
The derived pulse intensity integral of any point (r, is as shown in formula (2)PI (r.6)
Where:
is the characteristic acoustic impedance of water (see Appendix C). Note: The integration is performed in the time domain, T can be T, or TT. The measurement should be made using a focal hydrophone.
7.3.3 Derived focal acoustic pulse energy
a\(r,et)dt
GH/T 16407—2006/IEC61846:19981
(r.8,n)de
The focal acoustic pulse energy can be calculated from the derived pulse intensity integral focal domain transverse surface integral, as shown in formula (3): E
Note: The integration limit can be T, or T,
where,
P(r.,r)dsdt -
1 I (r,8)ds
p(r,0,t)——the sound pressure at any point (r,8) in time: S——the area within the 6dB equal pressure line passing through the focus and perpendicular to the beam axis (polar coordinates, spatial coordinates): z-
——the characteristic acoustic impedance of water (see Appendix C). 7, 3, 4 Derived acoustic pulse energy
The acoustic pulse energy can be derived from the integral calculation of the Lu strength in the cross-sectional area S with a radius of R, as shown in formula (4): ER =
p*(r,8,tdsd =
The R value is specified and the size of the stone can be simulated. P (r,gds ..
（2）
GB/T16407--2006/IEC61846:1998A. 1 Background
Appendix A
(Informative Appendix)
Ultraperitoneal lithotripsy
In many countries, kidney stones and ureteral stones are common. In Europe, the incidence is estimated to be 3% to 4% of the population. This figure does not include the common gallstones.
The usual treatment for kidney stones, ureteral stones and gallstones is invasive surgery, which requires the patient to stay in the hospital for 1 to 3 weeks and has a long recovery period. Since 1978, two new treatment methods, percutaneous ultrasonic lithotripsy and extracorporeal ultrasonic lithotripsy, have become increasingly important. Currently, there are more than 10,000 surgical procedures on the market. Clinical stone treatment, this method can not only reduce trauma, but is even non-invasive, which can shorten the hospitalization and postoperative recovery time. Both methods use high-intensity focused sound waves to break up the stones. The earliest ultrasound equipment using this method used a continuous wave sound source in direct contact with the patient. Extracorporeal lithotripsy uses sequence pulse pressure waves. Percutaneous laser lithotripsy is also valued due to its low surgical trauma. Since the 1990s, a large number of literatures have shown that the potential of high-intensity ultrasound in the treatment of diseases such as bone and joint pain, fracture recovery and muscle calcification has attracted more and more attention. A.2 Percutaneous continuous wave system
Using ultrasound The idea of ​​using acoustic energy to break up stones was first seen in 1953, but actual work was not reported until the 1970s. Although such equipment is still in production, it has not been widely adopted because the treatment time is too long. A.3 Limitations
This section does not discuss percutaneous continuous wave systems and semi-invasive laser lithotripsy. Although laser lithotripsy can combine local plasma and shock waves, this section only considers extracorporeal pressure pulse methods and equipment. A.4 Extracorporeal lithotripsy
Despite the high cost of extracorporeal lithotripsy, the clinical application of extracorporeal lithotripsy for breaking up stones has developed rapidly. In Germany, due to the high cost of this method It is non-invasive, has a short treatment time and a fast recovery, and is now very common in clinical practice. Different models of extracorporeal lithotripters can be purchased from different manufacturers. The key factor in clinical practice is to accurately determine the location of the stone and the location of the stone by the transducer focal column volume. This can be done by three-dimensional positioning using X-rays and B-ultrasound diagnosis, and the process of stone crushing can be monitored in real time using B-ultrasound. The duration of clinical treatment varies and mainly depends on the extracorporeal lithotripter system and the shape, location and size of the stone. The crushed kidney stone fragments are discharged through the ureter, bladder and urethra in the following days. For guanidinium stones, due to the special location of the stone and the softness of the stone, excretion is somewhat difficult.19987 Setup Procedure
Measurements shall be made under at least one of the clinical setup conditions specified by the manufacturer. If one setup condition is used, it shall produce the maximum effective output in clinical application and the setup condition shall be stated. Using the y-coordinate system, the direction of the axis is the beam axis. The following measurements will give the spatial characteristics of the beam: the axis is defined as the direction of the maximum beam width in a defined plane including the focal point. The distance between the focal point and the target position shall be noted. If the positive peak sound pressure at the target position does not differ by more than 10 degrees from that at the focal point, measurements may be made in the ! plane at the target position.
7.1 Spatial Measurements
The spatial distribution of the sound pressure shall be measured in the measuring trough. The maximum spatial sampling interval shall be 1 mm or 1/2 of the minimum width of the 6 dB isobar in the 2:3r plane, whichever is smaller, and 2 mm or 1/2 of the maximum dimension of the 6 dB isobar in the ? plane, whichever is smaller. If the difference between the sampling points is less than 10%, the interval between the sampling points can be expanded to 5 mm or 10 mm. Field hydrophones can be used, and the interval between the sampling points should be stated when giving the spatial distribution. Note 1: Before making other measurements, first make a measurement near its reference point to determine the focal position (see Appendix 3). Note: The focal position can only be accurately determined after the measurement of 7.1.1 is completed. Note 3: The hydrophone must be carefully selected to have sufficient linearity in the positive and negative pulse regions to ensure that no fluctuations occur during the measurement. 7.1.1 Positive Peak Sound Pressure Beam Pattern
The measurement includes the peak pressure in the xy plane at the focal point, and the -6 dB beam width is determined by the -6 dB isobars. The direction of the maximum beam width in the -y plane is selected and the -6 dB isobars in the -z plane and the -z plane are measured. : After measuring the positive sound pressure at each point in the axial direction, the pulse sound intensity integral can be calculated (see 7.3.1). Because the two curves are different, the areas calculated by the two curves will be quite different. 7.1.2 Negative peak sound pressure beam diagram
Measure the negative peak sound pressure on the surface of & and 2, and estimate the amplitude and position of the maximum negative sound pressure value. In fact, these measurements are relatively difficult, so the spatial sampling interval can be flexibly selected. If the difference in P_values ​​at each point does not exceed 10%, the sampling interval can be specified.
7.1.3 Focus point
The distance between the focal point and the moon mark should be determined, and its accuracy should be within ±2 mm in the axial direction and within ±3 mm in the axial direction.
7.1.4 Focal area width
According to the measurement in 7.1.1, the maximum focal area width f1 on the isoacoustic pressure line of 6dI3 in the y direction can be obtained. The focal area width f2 can be obtained in the orthogonal direction.
7.1.5 Focal area length
According to the isoacoustic pressure diagram of 6 dB on the surface in 7.1.1, the focal area length f2 between the isoacoustic lines of 6dI3 in the y direction can be obtained.
7.1.6 Focal area area
According to the spatial distribution, the focal area transverse area along the y-axis and the y-axis can be determined. Note: The focal area can be approximated as the area of ​​the circular surface with the axial lengths of t1, t2 and t3, respectively. 7.1.7 Focal volume
Based on the spatial distribution, the focal volume along the , and y axes can be obtained. Note: The focal volume can be approximated as a sphere with axis lengths of , , and y, respectively. 7.2 Time domain measurement
The focal hydrophone is placed at the focal position, and the difference between the measured positive peak sound pressure and the one given in the manual shall not exceed ±20. The pressure pulse waveform is measured at the point, and the following parameters are obtained: 6
Positive peak pressure and negative peak pressure:
Pulse width;
—Rise time.
7. 3 Acoustic energy measurement
7.3.1 Square integral of pulse sound pressure
The square integral of the pulse sound pressure at any point (r, y) is as follows: pi(r)=
Note: The integration limit T can be T, or T+.
7.3.2 Derived pulse intensity integral
The derived pulse intensity integral of any point (r, is as shown in formula (2)PI (r.6)
Where:
is the characteristic acoustic impedance of water (see Appendix C). Note: The integration is performed in the time domain, T can be T, or TT. The measurement should be made using a focal hydrophone.
7.3.3 Derived focal acoustic pulse energy
a\(r,et)dt
GH/T 16407—2006/IEC61846:19981
(r.8,n)de
The focal acoustic pulse energy can be calculated from the derived pulse intensity integral focal domain transverse surface integral, as shown in formula (3): E
Note: The integration limit can be T, or T,
where,
P(r.,r)dsdt -
1 I (r,8)ds
p(r,0,t)——the sound pressure at any point (r,8) in time: S——the area within the 6dB equal pressure line passing through the focus and perpendicular to the beam axis (polar coordinates, spatial coordinates): z-
——the characteristic acoustic impedance of water (see Appendix C). 7, 3, 4 Derived acoustic pulse energy
The acoustic pulse energy can be derived from the integral calculation of the Lu strength in the cross-sectional area S with a radius of R, as shown in formula (4): ER =
p*(r,8,tdsd =
The R value is specified and the size of the stone can be simulated. P (r,gds ..
（2）
GB/T16407--2006/IEC61846:1998A. 1 Background
Appendix A
(Informative Appendix)
Ultraperitoneal lithotripsy
In many countries, kidney stones and ureteral stones are common. In Europe, the incidence is estimated to be 3% to 4% of the population. This figure does not include the common gallstones.
The usual treatment for kidney stones, ureteral stones and gallstones is invasive surgery, which requires the patient to stay in the hospital for 1 to 3 weeks and has a long recovery period. Since 1978, two new treatment methods, percutaneous ultrasonic lithotripsy and extracorporeal ultrasonic lithotripsy, have become increasingly important. Currently, there are more than 10,000 surgical procedures on the market. Clinical stone treatment, this method can not only reduce trauma, but is even non-invasive, which can shorten the hospitalization and postoperative recovery time. Both methods use high-intensity focused sound waves to break up the stones. The earliest ultrasound equipment using this method used a continuous wave sound source in direct contact with the patient. Extracorporeal lithotripsy uses sequence pulse pressure waves. Percutaneous laser lithotripsy is also valued due to its low surgical trauma. Since the 1990s, a large number of literatures have shown that the potential of high-intensity ultrasound in the treatment of diseases such as bone and joint pain, fracture recovery and muscle calcification has attracted more and more attention. A.2 Percutaneous continuous wave system
Using ultrasound The idea of ​​using acoustic energy to break up stones was first seen in 1953, but actual work was not reported until the 1970s. Although such equipment is still in production, it has not been widely adopted because the treatment time is too long. A.3 Limitations
This section does not discuss percutaneous continuous wave systems and semi-invasive laser lithotripsy. Although laser lithotripsy can combine local plasma and shock waves, this section only considers extracorporeal pressure pulse methods and equipment. A.4 Extracorporeal lithotripsy
Despite the high cost of extracorporeal lithotripsy, the clinical application of extracorporeal lithotripsy for breaking up stones has developed rapidly. In Germany, due to the high cost of this method It is non-invasive, has a short treatment time and a fast recovery, and is now very common in clinical practice. Different models of extracorporeal lithotripters can be purchased from different manufacturers. The key factor in clinical practice is to accurately determine the location of the stone and the location of the stone by the transducer focal column volume. This can be done by three-dimensional positioning using X-rays and B-ultrasound diagnosis, and the process of stone crushing can be monitored in real time using B-ultrasound. The duration of clinical treatment varies and mainly depends on the extracorporeal lithotripter system and the shape, location and size of the stone. The crushed kidney stone fragments are discharged through the ureter, bladder and urethra in the following days. For guanidinium stones, due to the special location of the stone and the softness of the stone, excretion is somewhat difficult.19987 Setup Procedure
Measurements shall be made under at least one of the clinical setup conditions specified by the manufacturer. If one setup condition is used, it shall produce the maximum effective output in clinical application and the setup condition shall be stated. Using the y-coordinate system, the direction of the axis is the beam axis. The following measurements will give the spatial characteristics of the beam: the axis is defined as the direction of the maximum beam width in a defined plane including the focal point. The distance between the focal point and the target position shall be noted. If the positive peak sound pressure at the target position does not differ by more than 10 degrees from that at the focal point, measurements may be made in the ! plane at the target position.
7.1 Spatial Measurements
The spatial distribution of the sound pressure shall be measured in the measuring trough. The maximum spatial sampling interval shall be 1 mm or 1/2 of the minimum width of the 6 dB isobar in the 2:3r plane, whichever is smaller, and 2 mm or 1/2 of the maximum dimension of the 6 dB isobar in the ? plane, whichever is smaller. If the difference between the sampling points is less than 10%, the interval between the sampling points can be expanded to 5 mm or 10 mm. Field hydrophones can be used, and the interval between the sampling points should be stated when giving the spatial distribution. Note 1: Before making other measurements, first make a measurement near its reference point to determine the focal position (see Appendix 3). Note: The focal position can only be accurately determined after the measurement of 7.1.1 is completed. Note 3: The hydrophone must be carefully selected to have sufficient linearity in the positive and negative pulse regions to ensure that no fluctuations occur during the measurement. 7.1.1 Positive Peak Sound Pressure Beam Pattern
The measurement includes the peak pressure in the xy plane at the focal point, and the -6 dB beam width is determined by the -6 dB isobars. The direction of the maximum beam width in the -y plane is selected and the -6 dB isobars in the -z plane and the -z plane are measured. : After measuring the positive sound pressure at each point in the axial direction, the pulse sound intensity integral can be calculated (see 7.3.1). Because the two curves are different, the areas calculated by the two curves will be quite different. 7.1.2 Negative peak sound pressure beam diagram
Measure the negative peak sound pressure on the surface of & and 2, and estimate the amplitude and position of the maximum negative sound pressure value. In fact, these measurements are relatively difficult, so the spatial sampling interval can be flexibly selected. If the difference in P_values ​​at each point does not exceed 10%, the sampling interval can be specified.
7.1.3 Focus point
The distance between the focal point and the moon mark should be determined, and its accuracy should be within ±2 mm in the axial direction and within ±3 mm in the axial direction.
7.1.4 Focal area width
According to the measurement in 7.1.1, the maximum focal area width f1 on the isoacoustic pressure line of 6dI3 in the y direction can be obtained. The focal area width f2 can be obtained in the orthogonal direction.
7.1.5 Focal area length
According to the isoacoustic pressure diagram of 6 dB on the surface in 7.1.1, the focal area length f2 between the isoacoustic lines of 6dI3 in the y direction can be obtained.
7.1.6 Focal area area
According to the spatial distribution, the focal area transverse area along the y-axis and the y-axis can be determined. Note: The focal area can be approximated as the area of ​​the circular surface with the axial lengths of t1, t2 and t3, respectively. 7.1.7 Focal volume
Based on the spatial distribution, the focal volume along the , and y axes can be obtained. Note: The focal volume can be approximated as a sphere with axis lengths of , , and y, respectively. 7.2 Time domain measurement
The focal hydrophone is placed at the focal position, and the difference between the measured positive peak sound pressure and the one given in the manual shall not exceed ±20. The pressure pulse waveform is measured at the point, and the following parameters are obtained: 6
Positive peak pressure and negative peak pressure:
Pulse width;
—Rise time.
7. 3 Acoustic energy measurement
7.3.1 Square integral of pulse sound pressure
The square integral of the pulse sound pressure at any point (r, y) is as follows: pi(r)=
Note: The integration limit T can be T, or T+.
7.3.2 Derived pulse intensity integral
The derived pulse intensity integral of any point (r, is as shown in formula (2)PI (r.6)
Where:
is the characteristic acoustic impedance of water (see Appendix C). Note: The integration is performed in the time domain, T can be T, or TT. The measurement should be made using a focal hydrophone.
7.3.3 Derived focal acoustic pulse energy
a\(r,et)dt
GH/T 16407—2006/IEC61846:19981
(r.8,n)de
The focal acoustic pulse energy can be calculated from the derived pulse intensity integral focal domain transverse surface integral, as shown in formula (3): E
Note: The integration limit can be T, or T,
where,
P(r.,r)dsdt -
1 I (r,8)ds
p(r,0,t)——the sound pressure at any point (r,8) in time: S——the area within the 6dB equal pressure line passing through the focus and perpendicular to the beam axis (polar coordinates, spatial coordinates): z-
——the characteristic acoustic impedance of water (see Appendix C). 7, 3, 4 Derived acoustic pulse energy
The acoustic pulse energy can be derived from the integral calculation of the Lu strength in the cross-sectional area S with a radius of R, as shown in formula (4): ER =
p*(r,8,tdsd =
The R value is specified and the size of the stone can be simulated. P (r,gds ..
（2）
GB/T16407--2006/IEC61846:1998A. 1 Background
Appendix A
(Informative Appendix)
Ultraperitoneal lithotripsy
In many countries, kidney stones and ureteral stones are common. In Europe, the incidence is estimated to be 3% to 4% of the population. This figure does not include the common gallstones.
The usual treatment for kidney stones, ureteral stones and gallstones is invasive surgery, which requires the patient to stay in the hospital for 1 to 3 weeks and has a long recovery period. Since 1978, two new treatment methods, percutaneous ultrasonic lithotripsy and extracorporeal ultrasonic lithotripsy, have become increasingly important. Currently, there are more than 10,000 surgical procedures on the market. Clinical stone treatment, this method can not only reduce trauma, but is even non-invasive, which can shorten the hospitalization and postoperative recovery time. Both methods use high-intensity focused sound waves to break up the stones. The earliest ultrasound equipment using this method used a continuous wave sound source in direct contact with the patient. Extracorporeal lithotripsy uses sequence pulse pressure waves. Percutaneous laser lithotripsy is also valued due to its low surgical trauma. Since the 1990s, a large number of literatures have shown that the potential of high-intensity ultrasound in the treatment of diseases such as bone and joint pain, fracture recovery and muscle calcification has attracted more and more attention. A.2 Percutaneous continuous wave system
Using ultrasound The idea of ​​using acoustic energy to break up stones was first seen in 1953, but actual work was not reported until the 1970s. Although such equipment is still in production, it has not been widely adopted because the treatment time is too long. A.3 Limitations
This section does not discuss percutaneous continuous wave systems and semi-invasive laser lithotripsy. Although laser lithotripsy can combine local plasma and shock waves, this section only considers extracorporeal pressure pulse methods and equipment. A.4 Extracorporeal lithotripsy
Despite the high cost of extracorporeal lithotripsy, the clinical application of extracorporeal lithotripsy for breaking up stones has developed rapidly. In Germany, due to the high cost of this method It is non-invasive, has a short treatment time and a fast recovery, and is now very common in clinical practice. Different models of extracorporeal lithotripters can be purchased from different manufacturers. The key factor in clinical practice is to accurately determine the location of the stone and the location of the stone by the transducer focal column volume. This can be done by three-dimensional positioning using X-rays and B-ultrasound diagnosis, and the process of stone crushing can be monitored in real time using B-ultrasound. The duration of clinical treatment varies and mainly depends on the extracorporeal lithotripter system and the shape, location and size of the stone. The crushed kidney stone fragments are discharged through the ureter, bladder and urethra in the following days. For guanidinium stones, due to the special location of the stone and the softness of the stone, excretion is somewhat difficult.The interval between sampling points can be extended to 5 mm or 10 mm. Field hydrophones can be used. The interval between sampling points should be stated when the spatial distribution is given. Note 1: Before making other measurements, first make a measurement near the reference point to determine the focal position (see Appendix 3). Note: The focal position can only be determined accurately after the measurement in 7.1.1 is completed. Note 3: The hydrophone must be carefully selected to have sufficient linearity in the positive and negative pulse regions to ensure that no fluctuations occur during the measurement. 7.1.1 Positive Peak Sound Pressure Beam Pattern
The measurement includes the peak pressure in the xy plane at the focal point, and the -6 dB beam width is determined by the -6 dB isobars. The direction of the maximum beam width in the -y plane is selected and the -6 dB isobars in the -z plane and the -z plane are measured. The pulse sound intensity integral can be calculated after the positive sound pressure at each point in the axial direction is measured (see 7.3.1). Because the two curves are different, the areas calculated by the two curves will be quite different. 7.1.2 Negative peak sound pressure beam diagram
Measure the negative peak sound pressure on the surface of & and 2, and estimate the amplitude and position of the maximum negative sound pressure value. In fact, these measurements are difficult, so the spatial sampling interval can be fle
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