CN105249995A - Extracorporeal shock wave lithotripter adopting ultrasonic waves to position treatment points and positioning method thereof - Google Patents

Abstract

The invention discloses an extracorporeal shock wave lithotripter adopting ultrasonic waves to position treatment points and a positioning method thereof. A B ultrasound machine is mounted, so that accurate judgment for treatment points of the extracorporeal shock wave lithotripter by the B ultrasound machine becomes very difficult. Four ultrasonic transducers of the extracorporeal shock wave lithotripter disclosed by the invention are all fixed on a treatment head, and acoustic axes of the four ultrasonic transducers pass through the focus of the treatment head; the four ultrasonic transducers are connected with transducers cables; the four ultrasonic transducers cables extend out of a housing of the treatment head; one end of a cable lead is connected with a shock wave generation source; the other end of the cable lead extends out of the housing of the treatment head. The stone positioning method disclosed by the invention comprises the following steps: echoes of generated shock waves on a stone are used as a detection signal, and a signal acquisition system is used to process and analyze a received signal, so that the position of the stone and deviation conditions of the treatment points of the extracorporeal shock wave lithotripter are determined, and a basis is provided for adjusting the position of the extracorporeal shock wave lithotripter. According to the invention, the fact that shock waves and echo are spread in the same path is guaranteed and the ultrasonic detection accuracy is improved.

Description

Utilize extracorporeal shock-wave lithotomy instrument and the localization method thereof of ultrasonic locating point of care

Technical field

The invention belongs to medical ultrasound detection field, be specifically related to a kind of the extracorporeal shock-wave lithotomy instrument and the localization method thereof that utilize ultrasonic locating point of care.

Background technology

Extracorporeal shock-wave lithotomy instrument is the armarium pulverizing calculi in vivo, and this equipment produces shock wave in vitro, and inside of human body is carried out in propagation.Shock wave is in communication process, and energy is in the focal spot of about 1cm by constantly converging and be finally gathered in diameter, forms the shock wave that positive peak acoustic pressure is greater than 50MPa, negative peak acoustic pressure is greater than 2MPa.When running into the calculus being arranged in focal spot, powerful active force can be produced.Under the repeated action of shock wave, calculus can finally be pulverized, and is excreted.

In order to ensure effectiveness and the safety of extracorporeal shock-wave lithotomy instrument Clinical practice, calculus must be made to be in the focal spot of extracorporeal shock-wave lithotomy instrument, can ensure that shock wave energy acts in calculus effectively, therefore, the point of care of extracorporeal shock-wave lithotomy instrument is regulated and locates very important.At present, the location of extracorporeal shock-wave lithotomy instrument is realized by B ultrasonic and X-ray machine, B ultrasonic equipment and extracorporeal shock-wave lithotomy instrument are combined, judge whether calculus is in the focal spot of extracorporeal shock-wave lithotomy instrument by B ultrasonic image, when clinical treatment, then by observing the effect that X-ray judges to treat.Because B ultrasonic machine and extracorporeal shock-wave lithotomy instrument are the equipment that two covers are separated, therefore, B ultrasonic machine is installed and accurately can judges that the point of care of extracorporeal shock-wave lithotomy instrument is very difficult, particularly during actual use, because the position of calculus is different, patient will take different positions to treat, and doctor must adjust the position of Ultrasonic-B probe, thus the decline of equipment Position location accuracy can be caused, affect effectiveness and the safety of Clinical practice.

Summary of the invention

The object of the invention is for the deficiencies in the prior art, a kind of the extracorporeal shock-wave lithotomy instrument and the localization method thereof that utilize ultrasonic locating point of care are provided, measure shock wave echo-signal from calculus by using four ultrasonic reception transducers simultaneously, and use signal acquiring system to carry out to received signal processing and analyzing, the propagation time of four transducers is arrived by measuring echo-signal, calculate calculus position, and with the identical length of extracorporeal shock-wave lithotomy instrument focal regions, for the position of adjustment extracorporeal shock-wave lithotomy instrument provides foundation.

Apparatus of the present invention comprise seismic wave occurring source, cable tail, ultrasonic transducer, transducer cable, watertight capsule, aqueous medium and treatment head; The shell of described treatment head is positioned at seismic wave occurring source side and is processed with taper installation table top, install table top and equidistantly process four installing hole each self-retainings ultrasonic transducer, the acoustic axis of four ultrasonic transducers is all through treating the focus of head; Four ultrasonic transducers are all connected to transducer cable, and four transducer cables all stretch out outside the shell for the treatment of head; One end of described cable tail is connected with seismic wave occurring source, and the other end stretches out outside the shell for the treatment of head; Described watertight capsule is nested with on shell, and is filled with aqueous medium between watertight capsule and shell.

Described shell adopts stainless steel material.

The active material employing diameter of described ultrasonic transducer is 12mm, thickness is the piezoelectric ceramic wafer of 0.2mm, can receive the ultrasonic signal of 100 ~ 10MHz frequency range and be converted to the output of corresponding voltage waveform; The shell of described ultrasonic transducer is column type, and the taper on the acoustic axis of ultrasonic transducer and treatment head shell installs that table top is vertical to be arranged.

Described transducer cable is twin-core shielding watertight cable, and two heart yearns connect the active material positive and negative electrode of ultrasonic transducer respectively, and shielding line is connected with the shell of ultrasonic transducer; Cable one end is connected with ultrasonic transducer, and the other end stretches out outside the shell for the treatment of head.

The present invention carries out the method for calculus location, and concrete steps are as follows:

One end that step one, four transducer cables stretch out outside shell is all connected with signal sampler, and one end that cable tail stretches out outside shell is connected with driving power source; Driving power source sends the triggering signal of drive voltage signal as signal sampler; The output signal of signal sampler passes to the input of signal analyzer.

The position of step 2, coarse adjustment extracorporeal shock-wave lithotomy instrument, makes calculus near the focal regions of extracorporeal shock-wave lithotomy instrument; Start signal Acquisition Instrument and signal analyzer; By driving power source, extracorporeal shock-wave lithotomy instrument launching shock intensity of wave and operating frequency are set.

Calculus is located in angle and the position of step 3, fine tuning extracorporeal shock-wave lithotomy instrument.Using seismic wave occurring source center as the initial point of rectangular coordinate system xyz, four ultrasonic transducer positions in rectangular coordinate system are respectively P ₁(a, 0,0), P ₂(0, a, 0), P ₃(-a, 0,0), P ₄(0 ,-a, 0), the shock wave of seismic wave occurring source is propagated along z-axis, and at focus O ₁(0,0, z ₀) place's focusing; Wherein, a, z ₀all be not equal to 0.

(1) if calculus is positioned in the focus of shock wave, when shock wave sends from seismic wave occurring source, after calculus reflection by four ultrasonic transducers receive the time delay that produces identical, use t ₀represent:

$t_0=(z_0+\sqrt{z_0^2+a^2})/c---\left(1\right)$

Wherein, c is the spread speed of shock wave in aqueous medium.

(2) if calculus off-focal but still be positioned at the S (x of focal plane ₁, y ₁, z ₀) on point, now:

x ₁＝rcosθ

y ₁＝rsinθ

Wherein, r is the distance of S point to z-axis, and θ is the angle between S point and x-axis.

Shock wave from the time being applied to calculus after seismic wave occurring source sends is:

$t_0^{\′}=\frac{\sqrt{z_0^2+r^2}}{c\·}---\left(2\right)$

And the time that scatter echo arrives four ultrasonic transducers is respectively:

$t_1={(a^2-2ar\cos \mathrm{\θ}+r^2+z_0^2)}^{\frac{1}{2}}---\left(3\right)$

$t_2={(a^2-2arsin\mathrm{\θ}+r^2+z_0^2)}^{\frac{1}{2}}---\left(4\right)$

$t_3={(a^2+2ar\cos \mathrm{\θ}+r^2+z_0^2)}^{\frac{1}{2}}---\left(5\right)$

$t_4={(a^2+2arsin\mathrm{\θ}+r^2+z_0^2)}^{\frac{1}{2}}---\left(6\right)$

The total delay time that four ultrasonic transducers receive scatter echo is respectively:

T ₁＝t' ₀+t ₁；

T ₂＝t' ₀+t ₂

T ₃＝t' ₀+t ₃

T ₄＝t' ₀+t ₄

(3) due to t' ₀identical, when S point is arranged in first quartile, namely during 0< θ <90 °: T ₁< T ₃; T ₂< T ₄; When S point is arranged in the second quadrant, namely during 90 ° of < θ <180 °: T ₁> T ₃; T ₂< T ₄; When S point is arranged in third quadrant, namely during 180 ° of < θ <270 °: T ₁> T ₃; T ₂> T ₄; When S point is arranged in fourth quadrant, namely during 270 ° of < θ <360 °: T ₁< T ₃; T ₂> T ₄.

Therefore, the total delay time receiving scatter echo by monitoring four ultrasonic transducers judges the position residing for calculus, and then adjusts angle and the position of extracorporeal shock-wave lithotomy instrument.

In described step 2, when the shock wave of extracorporeal shock-wave lithotomy instrument transmitting is initial, select lower powered pulse mode and low operating frequency.

The output signal of described signal sampler to ultrasonic transducer gathers, record exported ultrasonic signal waveform; The sample frequency of signal sampler is 20MHz, and vertical quantified precision is 16bit; Signal sampler has the input channel of more than four, can gather the input signal of four ultrasonic transducers simultaneously; Signal sampler has outer signal and triggers input channel, carries out synchronous acquisition and the writing task of waveform under external signal triggers.

Described signal analyzer is analyzed the multichannel pulse echo signal that signal sampler records, and measures the propagation time of echo-signal received by four ultrasonic transducers.

The invention has the beneficial effects as follows:

(1) echo using extracorporeal shock-wave lithotomy instrument to produce in calculus is detectable signal, can reflect the effect situation of shock wave to calculus in real time, and accurately determine the position at calculus place.

(2) extracorporeal shock-wave lithotomy instrument wave source and ultrasonic listening transducer are coaxially installed, and ensure that shock wave is propagated with echo on identical path, improve the accuracy of ultrasonic listening.

(3) by the echo-signal of synchronous acquisition transducer, calculate the position at calculus place and the identical situation with extracorporeal shock-wave lithotomy instrument focal regions in real time, ensure that effectiveness and the safety of clinical treatment.

(4) instant invention overcomes use B ultrasonic equipment and carry out the intrinsic shortcoming in calculus location, the echo of the shock wave produced with extracorporeal shock-wave lithotomy instrument in calculus is detectable signal, and the wave source receiving ultrasonic transducer and extracorporeal shock-wave lithotomy instrument is coaxially installed, by receiving this echo-signal, and use signal acquiring system to carry out to received signal processing and analyzing, determine calculus place position and with extracorporeal shock-wave lithotomy instrument point of care depart from situation, thus provide foundation for adjusting extracorporeal shock-wave lithotomy instrument position, ensure that this kind equipment obtains more reliable and effective therapeutic effect in Clinical practice.

Accompanying drawing explanation

Fig. 1 is the assembling schematic diagram of apparatus of the present invention;

Fig. 2 is the connection diagram that the present invention and external meters equipment form echo-bearing system;

Fig. 3 is the shock wave echo-signal schematic diagram of the calculus reflection that in the present invention, ultrasonic transducer receives;

Fig. 4 is the fundamental diagram that the present invention utilizes shock wave echo-bearing.

Detailed description of the invention

Below in conjunction with accompanying drawing, the invention will be further described.

As shown in Figure 1, utilize the extracorporeal shock-wave lithotomy instrument of ultrasonic locating point of care, comprise seismic wave occurring source 1, cable tail 2, ultrasonic transducer 4, transducer cable 5, watertight capsule 6, aqueous medium 8 and treatment 9; The shell 3 for the treatment of 9 is positioned at seismic wave occurring source 1 side to be processed with taper table top is installed, table top is installed and equidistantly processes four installing hole each self-retainings ultrasonic transducer 4, the focus 7 of the acoustic axis ensureing four ultrasonic transducers all through treating 9; Four ultrasonic transducers 4 are all connected to transducer cable 5, and four transducer cables 5 all stretch out outside the shell 3 for the treatment of 9; One end of cable tail 2 is connected with seismic wave occurring source 1, and the other end stretches out outside the shell 3 for the treatment of 9; Watertight capsule 6 is nested with on shell 3, and is filled with aqueous medium 8 (degassed water) between watertight capsule 6 and shell 3, and tissue is fully contacted with watertight capsule 6, ensures that shock wave energy effectively propagates into inside of human body.

This utilizes the extracorporeal shock-wave lithotomy instrument of ultrasonic locating point of care, and operation principle is as follows:

1. as shown in Figure 2, extracorporeal shock-wave lithotomy instrument and external meters equipment form echo-bearing system.One end that four transducer cables 5 stretch out outside shell 3 is all connected with signal sampler 13, and one end that cable tail 2 stretches out outside shell 3 is connected with driving power source 10; Driving power source 10 is connected by triggering cable 11 with signal sampler 13, and driving power source 10 sends the triggering signal of drive voltage signal as signal sampler; The output signal of signal sampler passes to the input of signal analyzer 12.

2, debugging is initialized.Regulate the position of extracorporeal shock-wave lithotomy instrument, can be near the focal regions of extracorporeal shock-wave lithotomy instrument to make calculus; Start signal Acquisition Instrument and signal analyzer, and make them be in normal duty.Size and the operating frequency of extracorporeal shock-wave lithotomy instrument launching shock intensity of wave being set by driving power source 10, during initialization, in order to ensure the safety for the treatment of, selecting lower powered pulse mode and low operating frequency.

3, angle and the location positioning calculus of extracorporeal shock-wave lithotomy instrument is regulated.Obtain the calculus echo-signal received by four ultrasonic transducers by signal sampler simultaneously, and measured the time delay of the echo-signal that each ultrasonic transducer receives by signal analyzer.Shock wave has precipitous pulse front edge, and the typical waveform of the echo-signal reflected by calculus as shown in Figure 3.Using the drive voltage signal in driving power source 10 as triggering signal, measure the time delay T corresponding to pulse front edge of each ultrasonic transducer output signal ₁, T ₂, T ₃, T ₄, shock wave can be obtained from focus radiation, through calculus reflection, then by each ultrasonic transducer receive propagation time of experiencing.When calculus is arranged in the focal regions of extracorporeal shock-wave lithotomy instrument, the delay time that echo-signal arrives each ultrasonic transducer is identical, is set to t ₀if calculus is positioned at outside focal regions, then scatter echo arrives the propagation time of each ultrasonic transducer by different, and in the rectangular coordinate system of Fig. 4 definition, the coordinate position of four ultrasonic transducers is respectively P ₁(a, 0,0), P ₂(0, a, 0), P ₃(-a, 0,0), P ₄(0 ,-a, 0), then when calculus depart from z-axis be arranged in the 1st quadrant time, echo reaches P ₁, P ₂time will be less than P ₃, P ₄.Therefore, can regulate the angle of extracorporeal shock-wave lithotomy instrument, make calculus again be positioned at z-axis, then echo arrives the time delay of each ultrasonic transducer close to identical.If before or after calculus is positioned at extracorporeal shock-wave lithotomy instrument focal regions, then the time delay that ultrasonic transducer exports will be less than or greater than t ₀, now, the position regulating extracorporeal shock-wave lithotomy instrument can be passed through, until echo time delay is close to t ₀till.

Therefore, by monitoring the time delay that four ultrasonic transducers export, regulate angle and the position of extracorporeal shock-wave lithotomy instrument, the time delay of each ultrasonic transducer is near the mark time t ₀, can ensure that calculus can be in the focal regions of extracorporeal shock-wave lithotomy instrument.Now, pulse power can be strengthened and improve operating frequency, carrying out normal therapeutic.Over the course for the treatment of, by the time delay of each ultrasonic transducer of Real-Time Monitoring, and carry out the adjustment of extracorporeal shock-wave lithotomy instrument angle and position in time, can ensure that the safety of clinical treatment is with effective.

This utilizes the extracorporeal shock-wave lithotomy instrument of ultrasonic locating point of care to carry out the method for calculus location, and concrete steps are as follows:

One end that step one, four transducer cables 5 stretch out outside shell 3 is all connected with signal sampler 13, and one end that cable tail 2 stretches out outside shell 3 is connected with driving power source 10; Driving power source 10 is connected by triggering cable 11 with signal sampler 13, and driving power source 10 sends the triggering signal of drive voltage signal as signal sampler; The output signal of signal sampler passes to the input of signal analyzer 12.

The position of step 2, coarse adjustment extracorporeal shock-wave lithotomy instrument, makes calculus near the focal regions of extracorporeal shock-wave lithotomy instrument; Start signal Acquisition Instrument and signal analyzer; Extracorporeal shock-wave lithotomy instrument launching shock intensity of wave and operating frequency are set by driving power source 10, time initial, select lower powered pulse mode and low operating frequency.

Calculus is located in angle and the position of step 3, fine tuning extracorporeal shock-wave lithotomy instrument.Use operation principle that shock wave echo-signal positions calculus as shown in Figure 4, using seismic wave occurring source 1 center as the initial point O of rectangular coordinate system, four ultrasonic transducer positions in rectangular coordinate system are respectively P ₁(a, 0,0), P ₂(0, a, 0), P ₃(-a, 0,0), P ₄(0 ,-a, 0), the shock wave of seismic wave occurring source 1 is propagated along z-axis, and at focus O ₁(0,0, z ₀) place's focusing; Wherein, a, z ₀all be not equal to 0.

(1) if calculus is positioned in the focus of shock wave, when shock wave sends from seismic wave occurring source 1, after calculus reflection by four ultrasonic transducers receive the time delay that produces identical, use t ₀represent:

$t_0=(z_0+\sqrt{z_0^2+a^2})/c---\left(1\right)$

Wherein, c is the spread speed of shock wave in aqueous medium.

(2) if calculus off-focal but still be positioned at the S (x of focal plane ₁, y ₁, z ₀) on point, now:

x ₁＝rcosθ

y ₁＝rsinθ

Wherein, r is the distance of S point to z-axis, and θ is the angle between S point and x-axis.

Shock wave from the time being applied to calculus after seismic wave occurring source 1 sends is:

$t_0^{\&prime;}=\frac{\sqrt{z_0^2+r^2}}{c\&CenterDot;}---\left(2\right)$

And the time that scatter echo arrives four ultrasonic transducers is respectively:

$t_1={(a^2-2ar\cos \mathrm{\&theta;}+r^2+z_0^2)}^{\frac{1}{2}}---\left(3\right)$

$t_2={(a^2-2arsin\mathrm{\&theta;}+r^2+z_0^2)}^{\frac{1}{2}}---\left(4\right)$

$t_3={(a^2+2ar\cos \mathrm{\&theta;}+r^2+z_0^2)}^{\frac{1}{2}}---\left(5\right)$

$t_4={(a^2+2arsin\mathrm{\&theta;}+r^2+z_0^2)}^{\frac{1}{2}}---\left(6\right)$

The total delay time that four ultrasonic transducers receive is respectively:

T ₁＝t' ₀+t ₁；

T ₂＝t' ₀+t ₂

T ₃＝t' ₀+t ₃

T ₄＝t' ₀+t ₄

(3) due to t' ₀identical, when S point is arranged in first quartile, namely during 0< θ <90 °: T ₁< T ₃; T ₂< T ₄; When S point is arranged in the second quadrant, namely during 90 ° of < θ <180 °: T ₁> T ₃; T ₂< T ₄; When S point is arranged in third quadrant, namely during 180 ° of < θ <270 °: T ₁> T ₃; T ₂> T ₄; When S point is arranged in fourth quadrant, namely during 270 ° of < θ <360 °: T ₁< T ₃; T ₂> T ₄.

Therefore, by monitoring the total delay time that four ultrasonic transducers receive, the position residing for calculus can be judged, and then adjusting accordingly.

Claims (8)

1. utilize the extracorporeal shock-wave lithotomy instrument of ultrasonic locating point of care, comprise treatment head, it is characterized in that: also comprise seismic wave occurring source, cable tail, ultrasonic transducer, transducer cable, watertight capsule and aqueous medium; The shell of described treatment head is positioned at seismic wave occurring source side and is processed with taper installation table top, install table top and equidistantly process four installing hole each self-retainings ultrasonic transducer, the acoustic axis of four ultrasonic transducers is all through treating the focus of head; Four ultrasonic transducers are all connected to transducer cable, and four transducer cables all stretch out outside the shell for the treatment of head; One end of described cable tail is connected with seismic wave occurring source, and the other end stretches out outside the shell for the treatment of head; Described watertight capsule is nested with on shell, and is filled with aqueous medium between watertight capsule and shell.

2. the extracorporeal shock-wave lithotomy instrument utilizing ultrasonic locating point of care according to claim 1, is characterized in that: described shell adopts stainless steel material.

3. the extracorporeal shock-wave lithotomy instrument utilizing ultrasonic locating point of care according to claim 1, it is characterized in that: the active material employing diameter of described ultrasonic transducer is 12mm, thickness is the piezoelectric ceramic wafer of 0.2mm, can receive the ultrasonic signal of 100 ~ 10MHz frequency range and be converted to the output of corresponding voltage waveform; The shell of described ultrasonic transducer is column type, and the taper on the acoustic axis of ultrasonic transducer and treatment head shell installs that table top is vertical to be arranged.

4. the extracorporeal shock-wave lithotomy instrument utilizing ultrasonic locating point of care according to claim 1, it is characterized in that: described transducer cable is twin-core shielding watertight cable, two heart yearns connect the active material positive and negative electrode of ultrasonic transducer respectively, and shielding line is connected with the shell of ultrasonic transducer; Cable one end is connected with ultrasonic transducer, and the other end stretches out outside the shell for the treatment of head.

5. the extracorporeal shock-wave lithotomy instrument of ultrasonic locating point of care that utilizes according to any one of Claims 1 to 4 carries out the method for calculus location, it is characterized in that: the concrete steps of the method are as follows:

One end that step one, four transducer cables stretch out outside shell is all connected with signal sampler, and one end that cable tail stretches out outside shell is connected with driving power source; Driving power source sends the triggering signal of drive voltage signal as signal sampler; The output signal of signal sampler passes to the input of signal analyzer;

The position of step 2, coarse adjustment extracorporeal shock-wave lithotomy instrument, makes calculus near the focal regions of extracorporeal shock-wave lithotomy instrument; Start signal Acquisition Instrument and signal analyzer; By driving power source, extracorporeal shock-wave lithotomy instrument launching shock intensity of wave and operating frequency are set;

Calculus is located in angle and the position of step 3, fine tuning extracorporeal shock-wave lithotomy instrument; Using seismic wave occurring source center as the initial point of rectangular coordinate system xyz, four ultrasonic transducer positions in rectangular coordinate system are respectively P ₁(a, 0,0), P ₂(0, a, 0), P ₃(-a, 0,0), P ₄(0 ,-a, 0), the shock wave of seismic wave occurring source is propagated along z-axis, and at focus O ₁(0,0, z ₀) place's focusing; Wherein, a, z ₀all be not equal to 0;

(1) if calculus is positioned in the focus of shock wave, when shock wave sends from seismic wave occurring source, after calculus reflection by four ultrasonic transducers receive the time delay that produces identical, use t ₀represent:

$t_0=(z_0+\sqrt{z_0^2+a^2})/c---\left(1\right)$

Wherein, c is the spread speed of shock wave in aqueous medium;

(2) if calculus off-focal but still be positioned at the S (x of focal plane ₁, y ₁, z ₀) on point, now:

x ₁＝rcosθ

y ₁＝rsinθ

Wherein, r is the distance of S point to z-axis, and θ is the angle between S point and x-axis;

Shock wave from the time being applied to calculus after seismic wave occurring source sends is:

$t_0^{\&prime;}=\frac{\sqrt{z_0^2+r^2}}{c\&CenterDot;}---\left(2\right)$

And the time that scatter echo arrives four ultrasonic transducers is respectively:

$t_1={(a^2-2ar\cos \mathrm{\&theta;}+r^2+z_0^2)}^{\frac{1}{2}}---\left(3\right)$

$t_2={(a^2-2ar\sin \mathrm{\&theta;}+r^2+z_0^2)}^{\frac{1}{2}}---\left(4\right)$

$t_3={(a^2+2ar\cos \mathrm{\&theta;}+r^2+z_0^2)}^{\frac{1}{2}}---\left(5\right)$

$t_4={(a^2+2arsin\mathrm{\&theta;}+r^2+z_0^2)}^{\frac{1}{2}}---\left(6\right)$

The total delay time that four ultrasonic transducers receive scatter echo is respectively:

T ₁＝t' ₀+t ₁；

T ₂＝t' ₀+t ₂

T ₃＝t' ₀+t ₃

T ₄＝t' ₀+t ₄

(3) due to t' ₀identical, when S point is arranged in first quartile, namely during 0< θ <90 °: T ₁< T ₃; T ₂< T ₄; When S point is arranged in the second quadrant, namely during 90 ° of < θ <180 °: T ₁> T ₃; T ₂< T ₄; When S point is arranged in third quadrant, namely during 180 ° of < θ <270 °: T ₁> T ₃; T ₂> T ₄; When S point is arranged in fourth quadrant, namely during 270 ° of < θ <360 °: T ₁< T ₃; T ₂> T ₄;

Therefore, the total delay time receiving scatter echo by monitoring four ultrasonic transducers judges the position residing for calculus, and then adjusts angle and the position of extracorporeal shock-wave lithotomy instrument.

6. the method utilizing the extracorporeal shock-wave lithotomy instrument of ultrasonic locating point of care to carry out calculus location according to claim 5, it is characterized in that: in described step 2, when the shock wave of extracorporeal shock-wave lithotomy instrument transmitting is initial, select lower powered pulse mode and low operating frequency.

7. the method utilizing the extracorporeal shock-wave lithotomy instrument of ultrasonic locating point of care to carry out calculus location according to claim 5, is characterized in that: the output signal of described signal sampler to ultrasonic transducer gathers, record exported ultrasonic signal waveform; The sample frequency of signal sampler is 20MHz, and vertical quantified precision is 16bit; Signal sampler has the input channel of more than four, can gather the input signal of four ultrasonic transducers simultaneously; Signal sampler has outer signal and triggers input channel, carries out synchronous acquisition and the writing task of waveform under external signal triggers.

8. the method utilizing the extracorporeal shock-wave lithotomy instrument of ultrasonic locating point of care to carry out calculus location according to claim 5, it is characterized in that: described signal analyzer is analyzed the multichannel pulse echo signal that signal sampler records, measure the propagation time of echo-signal received by four ultrasonic transducers.