The BMUS guidelines for regular quality assurance testing of ultrasound scanners

Abstract

The provision of Ultrasound Quality Assurance (QA) across the UK is variable. In some areas, a comprehensive service is provided, usually by a Medical Physics Department, but many clinical ultrasound services have no formal QA programme. Where there is no formal QA programme, it might be expected that ultrasound users would report and ensure repair of obvious faults, such as mechanical damage or “drop-out”, but anecdotal evidence from around the country tells us that this is not always the case. On many modern scanners, faults are masked by advanced processing.

Professional bodies in the UK and around the world¹^–⁴ have been providing and updating ultrasound QA guidelines for over 35 years, but the implementation of QA has been inconsistent. There are many possible reasons for this inconsistency, including the lack of a legislative requirement, availability of Medical Physics services, sonography workload and a view that formal QA is unnecessary.

Legislation requires QA for other imaging modalities, where ionising radiations are used. The legislation is designed to protect staff, patients and members of the public from the effects of radiation, but enforcing bodies expect QA to include assessment of image quality as well as radiation dose. Medical Physics Departments do not all have expertise in ultrasound, and the distribution of Ultrasound Physicists around the country changes with retirements and career development moves. The most stable and consistent physics support for ultrasound seems to be where services are provided on a regional, rather than local, basis. Sonography workload is a growing issue for QA services, affecting both sonographer engagement and access to equipment.

The fairly widely held view that QA is unnecessary is challenged by the facts. In addition to anecdotal reports of failure of some users to report and remedy obvious faults, there is increasing evidence in the literature of the efficacy of formal QA programmes identifying more subtle deterioration of imaging performance.⁵^–⁹ Sonographers should note that in signing off a report, they are certifying that their equipment is fit for purpose.

The importance of QA for diagnostic equipment has been recognised in the UK by the Department of Health,10 the Care Quality Commission,¹¹ the National Health Service Litigation Authority¹² and the Medical and Healthcare Products Regulatory Authority.¹³ It will be a condition of contracts in the reforming National Health Service and is mandatory for ultrasound equipment used in NHS Screening Programmes.^2,14,15

The new emphasis on user testing in a number of recent QA guidelines^1–4 gives sonographers the opportunity to establish their own QA programme, even where there is no physics support for further testing and no test equipment. The tests are not time consuming, and some elements will already be carried out in departments complying with local infection control and equipment management requirements.

The aim of the QA guidelines published in this issue is to empower sonographers to take a leading role in demonstrating the consistency of performance of their equipment for the benefit of their patients. Please take up the challenge.

References

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10.

Department of Health. Diagnostic Tests – Direct Access Non-Obstetric Ultrasound Service. See https://www.supply2health.nhs.uk/AQPResourceCentre/AQPServices/PTP/Pages/DiagnosticTests.aspx (last checked 25 February 2013).

11.

CQC National Standards. See http://www.cqc.org.uk/public/what-are-standards/national-standards (last checked 18 February 2013).

12.

National Health Service Litigation Authority (NHSLA). NHSLA Risk Management Standards 2012–2013, London: NHSLA, 2012.

13.

Medical and Healthcare products Regulatory Authority (MHRA). Devices in Practice: A Guide for Professionals in Health and Social Care, London: MHRA, 2008.

14.

NHS Fetal Anomaly Screening Programme. 18⁺⁰ to 20⁺⁶ Weeks Fetal Anomaly Scan – National Standards and Guidance for England, Exeter: NHSFASP, 2010.

15.

NHS Abdominal Aortic Aneurysm Screening Programme. Essential Elements in Developing an Abdominal Aortic Aneurysm (AAA) Screening and Surveillance Programme, Gloucester: NHS AAA Screening Programme, 2011.