High-intensity focused ultrasound device and method for controlling piezoelectric driving device used in the same

Abstract

A high-intensity focused ultrasound (HIFU) device and a method for controlling the piezoelectric driving device achieve accurate and stable control as to movement of a transducer and a treatment position by use of a piezoelectric driving device configured to have a compact size in accordance with a great reduction in the size of a handpiece.

What is claimed is: 
     
         1 . A method for controlling a piezoelectric driving device to linearly move a transducer disposed in a cartridge of a high-intensity focused ultrasound handpiece, comprising:
 transmitting a high frequency signal to a piezoelectric motor, thereby causing the piezoelectric motor to generate piezoelectric ultrasound, and causing a piezoelectric driving shaft connected to the piezoelectric motor to generate vibration in accordance with the piezoelectric ultrasound;   coupling a piezoelectric operating unit provided with the transducer to the piezoelectric driving shaft, thereby causing the piezoelectric operating unit to move along the piezoelectric driving shaft in accordance with the vibration of the piezoelectric driving shaft; and   predetermining information as to positions, at which the transducer radiates ultrasound, and performing a control operation for stopping the movement of the piezoelectric operating unit along the piezoelectric driving shaft when it is sensed that the piezoelectric operating unit reaches one of the predetermined position, and irradiating ultrasound through the transducer.   
     
     
         2 . The method according to  claim 1 , wherein the control operation for stopping the piezoelectric operating unit and irradiating ultrasound through the transducer comprises:
 previously storing, in association with a position sensor to sense a position of the piezoelectric operating unit, sensing values respectively corresponding to a plurality of positions, at which the transducer radiates ultrasound, stopping an operation of the piezoelectric motor to stop the piezoelectric operating unit and controlling the transducer to radiate ultrasound when a sensed value of the position sensor generated during movement of the piezoelectric operating unit is equal to one of the stored sensing values; and   repeating the vibration generation, the movement of the piezoelectric operating unit along the piezoelectric driving shaft, and the ultrasound irradiation through the transducer so that the transducer sequentially radiates ultrasound at the positions respectively corresponding to the stored sensing values.   
     
     
         3 . The method according to  claim 1 , wherein:
 a magnet is provided at an end of the piezoelectric operating unit, and a plurality of Hall sensors is disposed in the cartridge, to sense a magnetic field of the magnet; and   the control operation for stopping the piezoelectric operating unit and irradiating ultrasound through the transducer comprises:   previously storing, in association with the Hall sensors, sensing values respectively corresponding to a plurality of positions, at which the transducer radiates ultrasound, stopping an operation of the piezoelectric motor to stop the piezoelectric operating unit and controlling the transducer to radiate ultrasound when one of sensed values of the Hall sensors generated during movement of the piezoelectric operating unit is equal to one of the stored sensing values; and   repeating the vibration generation, the movement of the piezoelectric operating unit along the piezoelectric driving shaft, and the ultrasound irradiation through the transducer so that the transducer sequentially radiates ultrasound at the positions respectively corresponding to the stored sensing values.   
     
     
         4 . The method according to  claim 1 , further comprising:
 moving the piezoelectric operating unit for a predetermined time after irradiation of ultrasound through the transducer at a last one of the predetermined positions;   moving the piezoelectric operating unit in an opposite direction; and   performing a control operation for stopping the movement of the piezoelectric operating unit along the piezoelectric driving shaft when it is sensed that the piezoelectric operating unit reaches one of the predetermined positions, and irradiating ultrasound through the transducer,   whereby a double shot of ultrasound is carried out at a treatment area through the transducer.   
     
     
         5 . A high-intensity focused ultrasound device for controlling a transducer disposed in a cartridge to linearly move and to radiate ultrasound for treatment, comprising:
 a piezoelectric driving device comprising a piezoelectric motor disposed in the cartridge, to generate piezoelectric ultrasound in accordance with a high frequency signal, a piezoelectric driving shaft connected to the piezoelectric motor, to generate vibration in accordance with the piezoelectric ultrasound, and a piezoelectric operating unit provided with the transducer and coupled to the piezoelectric driving shaft, to move along the piezoelectric driving shaft in accordance with the vibration of the piezoelectric driving shaft;   a position sensor for sensing a position of the piezoelectric operating unit;   a high frequency generator for generating a high frequency signal enabling the piezoelectric motor to generate piezoelectric ultrasound and a high frequency signal enabling the transducer to radiate ultrasound for treatment; and   a controller for predetermining information as to positions, at which the transducer radiates ultrasound, and controlling the high frequency generator performing a control operation for stopping the movement of the piezoelectric operating unit along the piezoelectric driving shaft when it is sensed that the piezoelectric operating unit reaches one of the predetermined positions, and irradiating ultrasound through the transducer.   
     
     
         6 . The high-intensity focused ultrasound device according to  claim 5 , wherein the controller previously stores, in association with the position sensor, sensing values respectively corresponding to a plurality of positions, at which the transducer radiates ultrasound, and controls the high frequency generator such that the piezoelectric motor stops and the transducer radiates ultrasound when a sensed value of the position sensor generated during movement of the piezoelectric operating unit is equal to one of the stored sensing values. 
     
     
         7 . The high-intensity focused ultrasound device according to  claim 5 , wherein:
 a magnet is provided at an end of the piezoelectric operating unit, and a plurality of Hall sensors is disposed at an area facing the magnet in a movement path of the piezoelectric operating unit within the cartridge while being spaced apart from one another by a predetermined distance; and   the controller previously stores, in association with the Hall sensors, sensing values respectively corresponding to a plurality of positions, at which the transducer radiates ultrasound, stops an operation of the piezoelectric motor to stop the piezoelectric operating unit and controls the transducer to radiate ultrasound when one of sensed values of the Hall sensors generated during movement of the piezoelectric operating unit is equal to one of the stored sensing values.   
     
     
         8 . The high-intensity focused ultrasound device according to  claim 5 , wherein the position sensor comprises an optical sensor installed at one side of the piezoelectric driving device, to emit light toward the piezoelectric operating unit, to receive the light reflected after being emitted, and to compare the received light with the emitted light, thereby sensing the position of the piezoelectric operating unit. 
     
     
         9 . A high-intensity focused ultrasound device for controlling a transducer disposed in a cartridge to linearly move and to radiate ultrasound for treatment, comprising:
 a piezoelectric driving device comprising a piezoelectric motor disposed in the cartridge, to generate piezoelectric ultrasound in accordance with a high frequency signal, a piezoelectric driving shaft connected to the piezoelectric motor, to generate vibration in accordance with the piezoelectric ultrasound, and a piezoelectric operating unit provided with the transducer and coupled to the piezoelectric driving shaft, to move along the piezoelectric driving shaft in accordance with the vibration of the piezoelectric driving shaft;   a high frequency generator for generating a high frequency signal enabling the piezoelectric motor to generate piezoelectric ultrasound and a high frequency signal enabling the transducer to radiate ultrasound for treatment;   an optical element array unit comprising a first optical element provided at one side of the piezoelectric operating unit, the first optical element being one of a light emitting element and a light receiving element, and an optical element array provided at an area facing the first optical element, the optical element array comprising a plurality of second optical elements each being the other of the light emitting element and the light receiving element, so that light reception is achieved between the first optical element and the second optical elements during movement of the piezoelectric operating unit along the piezoelectric driving shaft; and   a controller for controlling the high frequency generator to enable the piezoelectric operating unit to move in accordance with vibration generated by the piezoelectric ultrasound and to enable the transducer to radiate ultrasound, stopping the piezoelectric operating unit when the light reception is achieved by the optical element array device, and irradiating ultrasound through the transducer.