Destruction of concretions by combined treatment.

p0001The invention relates to a process for the comminution of concretions in the bodies of living beings, a device for carrying out the method and the commercial use of products to the aforementioned method.

p0002From EP 225 104 A1 it is known to use for gallstone comminution ultrasonic fields along with a lytic agent, which was introduced by means of a catheter.

p0003It has already been proposed (German patent application P 37 08 325) to crush gallstones with shock waves and then with shock waves of low energy the Bruckstuecke to move in a lyse, which was entered with a catheter. Instead of the shock waves is also provided to use ultrasonic waves lesser strength.

p0004Object of the invention is to propose a method, faster, and minimize stressful for patients, can be crushed with the concrements in bodies of living beings, especially kidney stones, gallstones or gallbladder stones.

p0005This object is inventively solved by method comprising the steps specified in the claims. Professional uses and devices are objects of the dependent claims.

p0006Essence of the invention is the combination of two in themselves known treatment methods, namely the extracorporeal shock wave lithotripsy and the ultrasonic treatment simultaneously or sequentially. It has been found that the combination of shock wave and ultrasonic treatment results in a substantially faster dissolution of the stones, as was to be expected, individual measures for both. The synergistic effect is probably due to the fact that the shock waves are working particularly effective when there are in the stone around cavitation nuclei, for example, were produced by ultrasound or by chemical means, which improve the cavitation.

p0007In the invention, it is preferably a non-invasive method of treating lithiasis, particularly gallstones, gallbladder stones or kidney stones. One advantage is that the combination of shock waves and ultrasound treatment - preferably in conjunction with a Litholyse - the stones are crushed quickly and the time needed to reach complete stone clearance is considerably shortened. The invention is distinguished from the separate process by the fact that an optimal effect is achieved by appropriate combination of methods. This results in a considerably reduced burden on the patient and an extension of the indication region.

p0008Preferably, prior to, during and after treatment decreased the lithogenic index of the surrounding liquid the concrement through oral administration of drugs; That is, it is, for example, generates a cholesterinuntersättigte bile into the gallbladder. These are currently being chenodeoxycholic, ursodeoxycholic acid and a combination of the two funds. However, it is also possible, the environment of the stones by an appropriate diet or - to change by injecting water into the gallbladder - invasive. This means that already by a dietary treatment may be altered to the environment of the stone that the resolution of the stone is much faster by ultrasound.

p0009The solitary and multiple stones are crushed by the shock waves generated extracorporeally. The crushing effect and the dissolution rate of the remaining stone fragments is increased by the application of high intensity ultrasound. This procedure can be used in several ways: - Shockwave application under continuous ultrasound exposure of the stone - Shock wave application with ultrasound exposure in the treatment breaks - Shock wave application with ultrasonic exposure followed.

p0010The ultrasonic treatment after the shock wave treatment may extend over several days and are repeated several times daily.

p0011In the ultrasonic transducer can be either be a focusing, in part focusing or planar oscillator. focused on the stone surrounding shockwaves have very few side effects. The ultrasound exposure can either be continuous or intermittent, ie, the pulse length, the period and the repetition can be freely selected, whereby an optimal adjustment to the stones can be achieved.

p0012The intensity of the oscillator is in the therapeutic range, should for reasons of tissue damage to a peak of about 15 W / cm but not exceeding. The operating frequency is in the range between 10 Hz and 500 kHz, preferably between 10 kHz and 500 kHz. Low-frequency ultrasound is be-especially in connection with chemical Lysemitteln.

p0013In the ultrasonic transducer may be a separate from the shock wave source oscillator, or an oscillator, low energy or sinusoidal ultrasonic waves can be generated with the optional shock waves of high energy shock waves.

p0014Besides sinusoidal ultrasonic waves also shock waves of low energy and high repetition rate (60 Hz to 200 kHz) can be applied.

p0015It has been found that fragmentation of gall bladder stones and renal calculi by shock waves is strongly dependent on the ambient pressure. This dependence can be explained by the fact that the destruction of these stones is dependent mainly by cavitation and subsequent Kavitationsblasenkollaps in stone and its immediate surroundings. The cavitation is thus largely dependent on the Kavitationskeimdichte in stone and its surroundings directly during shock wave application.

p0016According to the invention the stone Kavitationskeimdichte of the surrounding medium optimized by suitable choice of the quasi-stationary local state parameters, in particular by suitable choice of the surrounding medium. The relevant parameters are: - Low vapor pressure, low viscosity, - Vaccination with Kavitationskeimen, - Administration of contrast media with a tendency of cavitation, - Ultrasonic irradiation.

p0017The Kavitationskeimdichte in stone is increased by prior treatment with ultrasonic waves. The Kavitationskeimdichte is also significantly affected by the shock wave application during the ultrasonic irradiation.

p0018Another explanation for the surprisingly good effect of the combination of this invention may be that ultrasound and shockwave lead locally in stone by constructive or destructive interference at elevated pressure and higher tensile or pressure gradients. The shock waves and the ultrasonic waves can be directed from the same or from different directions to the stone. By varying the operating frequency of the ultrasonic generator improving Stone resolution can be achieved by generating resonance effects in the cavitation bubbles or in stone.

p0019In addition to shock waves of high energy that produce the lithographs in k-bar area, also shock waves of low energy, the prints can generate several bar in the area, are ver turns. However, the weaker shockwaves should then be used with higher refresh rates.

p0020The invention is illustrated by three figures.

p0021Show it:<ul><li>1 shows a focusing, piezoelectric oscillator,</li><li>2 shows the waveforms generated by the piezoelectric oscillator and</li><li>3, the combined use of shock waves, and ultrasound.</li></ul>

p0022Figure 1 schematically shows a piezoelectric transducer, which directs a focused sound field on the stone, which is in the focus of the transducer.

p0023Figure 2 shows three different waveforms which can be generated by the vibrator shown in FIG. 1 Top left of the response of a shock wave is shown, the maximum pressures in focus are in the range of kbar. Right above the pressure course of several shock waves of lower energy is shown. The prints in the focus range of several or tens-bar, the repetition is for much higher than for the individual, strong shock wave, as shown left. Links below the pressure profile of an ultrasonic wave is shown. The pressures vary in the bar area.

p0024Figure 3 below shows a shock wave source, the shock waves are generated by spark discharge and here passed over the reflector to the stone in the body of the patient. Links an ultrasonic transmitter is shown, which sends a unfocused ultrasound field here in the stone field. Both devices can be operated independently or correlated with one another. The choice of the entrance window in the patient's body is arbitrary. The initiation of shock waves or ultrasound waves takes place as usual on pillows or by means of a liquid bath.