The Development Of Two-dimensional High Intensity Focused Transducer

In the clinical treatment of tumors, High intensity focused ultrasound(HIFU) treatment technology as a non-invasive tumor heat treatment technology, has been used in the treatment of liver cancer, uterine fibroids, breast cancer, renal cancer, pancreatic cancer and other deep abdominal solid tumors.Array of spherical ultrasonic therapy transducer is a new type of transducer of the system, which has become a hot research for scientists. It completes electronic scanning treatment through electronic focusing flexibly and fast. however, its complex structure and the characteristics of multi-parameters needed to design of array eventually lead to the difficulty on design and manufacture.How to get an ideal focusing effect of multi-array spherical ultrasonic therapy transducer with a simple design and manufacturing method at lower cost, that has become one of the research directions for scientists.This paper proposes a novel design method for HIFU transducer, arrange a limited number of the same shape and size of a regular hexagonal planar ceramic plate onto the layout of spherical dome densely, in order to create a low-cost high-intensity focused ultrasound probe.This paper mainly includes two parts. First, building a platform suitable for developing two-dimensional high-intensity focused ultrasound probe. The platform includes a design platform for developing spherical dome therapy array, and a Manufacturing Solution for the HIFU probe by using 3D printing and CNC technology. the probe platform has the value for scientific research and application, and basically meet the demand for the HIFU treatment probe design and development, and provides a simple, low cost, fast probe technology manufacturing solutions as well. Finally, with the platform, this paper developed a number of array elements 125, hexagonal array element side length of 2.5mm, the resonant frequency of 2MHz, the radius of curvature of 60 mm multi-element array of spherical dome HIFU probe. The simulation result shows that: its focal region the size of 1.5×1.5×7.5mm3, the focal plane of maximum deflection range of 6mm, along the axial direction of the beam emission maximum deflection distance of 6mm. In addition, the experiment results shows that a short pulse excitation, the minimum size of the physical focus of the focal region up 1×1×3mm3, its best operating frequency of 2.1MHz. So, through theoretical and experimental results comparing the sound field characteristic of the probe, it proved the feasibility of HIFU treatment probe development platform.