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The Medical Devices Directive

This page contains the report of the working party investigating the MDD and how it will work in the Institute, there are links to several documents and examples of how the proposed forms will work.

In the division we have set up a procedure to ensure that our new MR pulse sequences and analysis programs comply with the Medical Devices Directorate. We are starting from the frame work that Geoff Cusick at UCLH has given us, then applying these guidelines to the MR devices that we develop.
The motivation is to improve the scientific quality and reliability of our work, and also to cover ourselves from any personal liability issues. It is planned to do this with minimal bureaucracy and maximal improvement in our devices. Some immunity from liability is also given by having ethics permission for our imaging.

The MDD and Quantitative Magnetic Resonance

A talk on this topic was given at the IPEM THE SOFTWARE MEDICAL DEVICE 12th November 2004 BIR Conference Suite, London by Paul Tofts and Geoff Cusick

Abstract

The MDD does not necessarily formally apply to  Magnetic Resonance sequences or the resulting image analysis programs that are developed in house. Yet personal indemnity remains an issue for many physicists, who have at times paid for indemnity insurance. Compliance with MDD requirements is a convenient way of demonstrating good practice to both the employer and the courts, in the case of an accident or of an incorrect measurement being used to guide treatment. In addition, compliance may improve the scientific quality of the work, particularly in the design of efficient validation procedures. MR has a series of safety issues, which are largely covered by the manufacturer's FDA approval (unless/until the scanner is operated in research mode). Quantitative aspects bring a new set of Essential Requirements that must be considered, around issues of validation and specifying the accuracy and precision of the measuring device. Experience from the design of other types of medical device will probably be relevant here. The relevance of an 'uncertainty budget, as used in modern measurement science, as a replacement for the traditional notions of accuracy and precision, should also be considered.  Case studies from MR pulse sequence design and image analysis will be presented.

Roadmap for a device provider

  1. See which Essential Requirements apply to your device
  2. Look at one of the examples below

Relevant documents

MDD_ER_checklist_MR  the essential requirements (ER) MDD checklist, answered for MR

MDD_MR1_generic_response   generic response to much of the MR-relevant parts of the ER document

MDD_MR2_questionnaire  the remaining questions that must be answered with specific responses by the MR physicist

MDD_MR3_guidance &nbspguidance to the MR physicist in making the specific responses

Image analysis example: Texture analysis by Dr. Dan Tozer

Pulse sequence example MDEFT
sequence
for Siemens Sonata - questionnaire


There was a working party of one person from each MR group at Queen
Square: Dan Tozer, Louis Lemieux,  Ralph Deichmann, John
Thornton, David Thomas, Paul Tofts. 


This was discussed in detail at the Divisional meeting on January 17th 2005.

The documents were tested by the working party, which met again on April 21st. 


Two responses (see examples above) were presented in final form at the Divisional meeting on July 4th 2005. Please use these as templates for any device you may wish to describe.