What’s the high intensity focused ultrasound transducer

High intensity focused ultrasound HIFU is an emerging in vitro non-invasive treatment of tumor technology. The physical principle of treatment is: through a certain form of ultrasound focusing transducer, the ultrasound energy is focused on the target tissue, and the target tissue is rapidly heated to above 65 degrees in 1 s, resulting in protein denaturation, thereby causing irreversible coagulation of the target tissue. Necrosis, for non-invasive treatment purposes. The HIFU transducer is a core component of the HIFU treatment device. Therefore, the design of the transducer has become a key issue in HIFU treatment.

HIFU transducer research history related to HIFU beauty sensor transducer research, can be traced back to the 20th century high intensity focused ultrasound is a new in vitro non-invasive treatment of tumor technology. The physical principle of treatment is: through a certain form of ultrasound focusing transducer, the ultrasound energy is focused on the target tissue, and the target tissue is rapidly heated to above 65 in 1 s, resulting in protein denaturation, resulting in irreversible coagulative necrosis of the target tissue. To achieve non-invasive treatment purposes. The HIFU transducer is a core component of the HIFU treatment device. Therefore, the design of the transducer has become a key issue in HIFU treatment. HIFU transducer research history related to HIFU transducer research, can be traced back to the 20th century * National Ministry of Education Innovation Team Development Program project funding and National Outstanding Youth Fund-funded project mechanical adjustment treatment bed, can achieve accurate positioning and scanning of lesions treatment.

Focused ultrasound transducer classification

According to the contact with the body surface, the therapeutic HIFU piezoceramic transducer can be divided into two categories: one is the intracavitary treatment transducer, which is currently used to treat urinary system diseases. This type of transducer is characterized by small size and short focal length. FocusSurgery's line of devices for the treatment of prostate disease uses a treatment head for intracavitary treatment transducers that uses mechanical scanning to create large focal spots. The other type is an in vitro focus transducer, which is characterized by a large diameter, a long focal length, and a high energy ratio. The external focus transducer mainly has an acoustic lens focus transducer, a spherical autofocus transducer, a multi-element self-focusing transducer, and an electronic phased array focus transducer, which are respectively described below.Acoustic Lens Focusing Transducer Acoustic lens focusing is one of the commonly used acoustic focusing methods. The principle is to use the refraction of sound waves at the curved interface to achieve the purpose of collecting sound waves. Commonly used acoustic lens materials are aluminum, plexiglass, and the like. In the treatment, the general power is not large, the use of plexiglass, and at high power, because the plexiglass is not resistant to high temperatures, aluminum is generally used. It has been found that the shape of the coagulative necrosis produced by the division of the acoustic lens by different segmentation methods is quite different from that of the temperature field. A suitable division shows a good temperature field distribution, and the resulting coagulative necrosis shape is more regular. The 3D hifu transducer treatment system uses an acoustic lens focusing transducer, and the transducers of different focal lengths can be replaced according to clinical requirements to achieve adjustable focal length.

Spherical self-focusing transducer
The spherical HIFU piezo ceramic transducer is made by grinding the piezoelectric ceramic into a spherical surface, then being polarized and plated with silver, and the radiation has a focusing characteristic. This type of transducer can be sized according to different depths, and mechanical scanning is generally used during work. Spherical self-focusing transducers are relatively simple in theoretical analysis and power amplifier control system design. They have mature analysis and design methods, and it is easy to realize the ideal shape of the focal region. There is a spherical self-focusing transducer with a frequency of 7MHz, the focal length is 140mm, the transducer is mounted on a robot, and the degree of freedom is three-dimensionally rotated. The transducer is placed in a water bag and the ultrasound is directed down through the water bag (containing degassed water) into the tissue.

Multivariate self-focusing transducer

Multi-element self-focusing transducers typically consist of no more than 10 unit transducers. Such transducers generally arrange a plurality of piezoelectric ceramic sheets on a spherical concave surface of several tens of centimeters in diameter to form a high energy density region. If the special three-dimensional surface self-focusing method is adopted, the focus of each unit transducer can be concentrated to the same point, supplemented by the matching of the ultrasonic power source and the transducer, and the phase consistency and amplitude consistency can be adjusted. Very good focus sound field distribution. A series of high-energy focused ultrasound oncology machines with multi-sphere self-focusing transducers.