Equipment, measurement and dose-a survey for therapeutic ultrasound

Abstract

Background: Dosimetry for Ultrasound Therapy (DUTy) is a large international project which addresses the development of a metrological infrastructure for the determination of ultrasound exposure and dose to tissue.

Methods: In order to seek the views of the wider therapy ultrasound community and to review dose and in situ exposure quantities that have been suggested or used previously, a web-based questionnaire containing a range of questions covering the type of ultrasound equipment that is used and the range of applications for which it has been developed was created at www.surveymonkey.com. This questionnaire was intended to cover any contemporary therapeutic ultrasound application (including physiotherapy, lithotripsy and drug delivery) and asked specific questions about quantification of in situ exposure and dose, especially as relevant to treatment planning, standardisation and/or regulation.

Results: This paper summarises the 123 responses submitted between February and September 2014 to the questions on clinical applications, equipment, quality assurance (QA) and measurement and standards, as well as to those relating to an understanding of "dose" in the context of ultrasound. The full set of anonymous responses is available in an additional Excel file.

Conclusions: The results clearly demonstrate the need not only for further improvements in measuring devices and for measurement guidelines but also for a wider dissemination and higher awareness of existing standards. Whilst it is unlikely that a single definition of dose can be sufficient for all ultrasound treatment modalities, the answers clearly indicate that many aspects would benefit from clear definitions of relevant dose quantities and shed light on the preferred form of such definitions.

Keywords: Dosimetry; Exposimetry; Survey; Therapeutic ultrasound.

Fig. 1

Responses to questions Q1 (a), Q4 (b) and Q2 (c) related to clinical applications. Multiple answers were possible (“Please tick all that apply”)

Fig. 2

Responses to question Q3. Each respondent’s total does not have to add up to 100 %

Fig. 3

Responses to questions Q5 to Q8 (a–d) related to equipment characteristics. Multiple answers were possible (“Please tick all that apply”)

Fig. 4

Responses to questions Q9 to Q11 (a–c) related to equipment characteristics. Multiple answers were possible (“Please tick all that apply”)

Fig. 5

Responses to questions Q13 to Q15 (a–c) related to measurements made. Multiple answers were possible (“Please tick all that apply”)

Fig. 6

Responses to questions Q17 (a), Q19 (b) and Q20 (c) related to the measurements made. Multiple answers were possible (“Please tick all that apply”)

Fig. 7

Responses to questions Q21 related to the determination of the therapeutic effectiveness. Multiple answers were possible (“Please tick all that apply”)

Fig. 8

Responses to questions Q22 to Q24 (a–c) about the awareness of IEC standards related to ultrasound

Fig. 9

Responses to question Q25 about perceived shortcomings of current measurement methods

Fig. 10

Responses to questions Q27 (a) and Q28 (b) about general and personal usage of the word “dose”

Fig. 11

Responses to questions Q30 (a) and Q31 (b) about possible benefits of a better understanding of “dose” and possible characteristics of “dose”