Transducers specifications
From application to transducer

Imasonic HIFU transducers in their operating environment

image1 courtesy Insightec
13aja7028incrustation_3 courtesy Theraclion
edap2hr_-_copie courtesy EDAP TMS

Input parameters

Each application is specific, and requires knowledge and consideration of the uniqueness of all the data that contributes to the performance, reliability and security of the device.

The world-wide sharing of data on the issues of the application and the transforming of these issues into characteristics and constraints applicable to the transducer are the essential steps for defining the transducer solution adapted to the final needs and goals.

The figure on the right illustrates the main parameters to be taken in this framework.

Checklist of the required characteristics

Main features of the transducer

  • Frequency
  • Number of elements
  • Element pattern for array transducers (linear, annular, matrix, other)
  • Active dimensions
  • Focal distance
  • Mechanical dimensions / drawing of the casing
  • Required connection (position of the cable output, cable length, type of connector, pinout diagram)

Detailed conditions of use

  • Description of the environment of the transducer: complete or local immersion, nature of the coupling medium, presence of a membrane, fluid volume/circulation, temperature/regulation of the coupling fluid, orientation of the transducer
  • Excitation conditions: type of excitation signal, number of cycles ON or duration ON, time OFF or repetition frequency
  • Description of the driving electronics: output electric impedance, available electric power (total, per channel), Voltage Standing Wave Ratio

Normative requirements

  • Translation of the standard and legal requirements into requirements applicable to transducers (biocompatibility, electrical safety, other)

Other

  • MRI compatibility
  • Special tests or measurements
  • Information about the application
  • Context of the development (research, proof of concept, feasibility study, clinical evaluation, pre-series, etc.)

Long term perspectives/collaboration

  • A high-power transducer is developed as per the agreed specifications, and is measured and tested in order to check its conformity at the time of delivery. However, many parameters can influence its durability, and the precise knowledge of the behavior and the ageing of the transducer in the specific conditions of use and implementation shall be evaluated in a separate and dedicated action plan.