Vascular ultrasound treatment device with a flexible waveguides

The device is classified in the field of medical devices, specifically endovascular surgery, and can be used for cardiovascular surgery.

There is a known vascular invasive cleaning device consisting of an ultrasonic generator connected to an electromechanical transducer with a flexible waveguide and a suction system (see The CROSSER ™ System by FlowCardia, lnc)

In the specified device, the inner walls of the blood vessels are cleaned by introducing the waveguide into the blood vessel, its occlusion site, and by generating high frequency mechanical vibrations in the waveguide from the generator. Because the oscillator generates waveguide oscillations at 20,000Hz resonance frequency and vascular plaques and thrombi vary in consistency, resulting in a mechanical load on the waveguide and hence its resonant oscillation frequency, the amplitude of the waveguide oscillation is not always sufficient to completely remove the thrombi. As a result, the process of vascular cleansing is not fully effective.

There is known a device for internal vascular cleaning consisting of a catheter with an ultrasound transfer unit located in the inner part of the catheter and connected directly to the ultrasound generator. The free end of the ultrasonic transmission unit-waveguide is in the form of a spherical head, which may slip out of the catheter and may include a neck or radial groove (tubular) with a cutting edge (see EU Patent No. 0835644A2, published April 15, 1998).

In the above prototype, vascular cleaning is performed by a waveguide, in which mechanical oscillations are excited from the ultrasonic generator. Due to the curvature of the free end of the waveguide in accordance with the vascular profile, its amplitude changes due to its acoustic-mechanical characteristics. Unstable amplitude of waveguide free end vibration

Z in the curved part of the vessel only partially removes the resulting atherosclerotic structures inside the vessel.

The goal is to increase the efficiency of cleaning the inner walls of blood vessels.

The object of the present invention is achieved by the fact that an internal vascular cleaning device consisting of a flexible metal waveguide, an ultrasonic transducer and an ultrasonic generator with a microcontroller controlled system pre-writes the resonant frequencies of the special generator control program, whereby the oscillator scans the frequency within a given range between two frequencies. In this way, the oscillator at the free end of the waveguide generates linear and curvilinear waveguide resonant frequency oscillations from the generator.

The invention is explained in the drawing.

The device comprises a programmable ultrasonic generator 1, an ultrasonic transducer 2, a flexible waveguide 3, a coupling 4, a catheter 5, a suction device 6, a free-spherical head 7 of the waveguide.

The cleaning of the inner walls of blood vessels is done as follows.

Prior to cleaning, the control program of the ultrasonic generator 1 is compatible with the oscillations of the two resonant frequencies of the waveguide 3, between the lower and the upper, depending on the bending angle of the waveguide and for this purpose a flexible waveguide is attached to the ultrasonic transducer 2. 4 is connected to the suction unit 6. An electrical signal from the ultrasonic generator 1 through the ultrasonic transducer 2 excites the mechanical oscillations of the free end spherical head 7 of the flexible waveguide 3. With the waveguide 3 in the linear position, the first longitudinal resonant oscillation frequency is determined and recorded in the control program of the ultrasonic generator 1. The flexible waveguide 3 is then bent at an angle to perform a cleaning operation in the vessel and the second frequency of the longitudinal resonant oscillation of the flexible waveguide 3 is recorded and recorded in the ultrasonic generator 1 control program. The ultrasonic oscillator 1 is set to operate in the floating frequency mode and an excitation signal is applied to the ultrasonic transducer 2, whose frequency varies uniformly between the first and second longitudinal resonant frequencies corresponding to the resonant frequencies of the straight and curved waveguides. After performing the alignment, the flexible waveguide 3 is introduced into the blood vessel through the sleeve 4 and the catheter 5, and a suction device 6 and an ultrasonic generator 1 with a predetermined operating mode are actuated. The vascular cleansing performed in this way completely cleans the inner surface of the blood vessels, thereby increasing cleaning efficiency.

Compared to the prototype, the floating frequency control program in the ultrasonic generator allows the required amplitude of the waveguide oscillations to be maintained irrespective of the waveguide bending angle, which ensures complete cleaning of the vessel's internal surface from clogging, thus increasing cleaning efficiency.