Objectives

1. To establish a consensus for the optimisation of new detectors for radiology and dentistry, and nuclear medicine
2. To establish strategies for patient dose management based upon published information
3. To develop acceptance, status and constancy test protocols for new detectors by building upon existing experience

Description of work

1. Refine quality criteria for digital radiology using new digital detectors
2. Collation of performance survey of image post processing algorithms
3. Collation of patient dosimetry data
4. Optimisation studies of post processing algorithms based upon literature data

Deliverables

1. Review and consensus on approaches to digital detected, general radiology and nuclear medicine equipment performance.
2. Review and Survey of dosimetry data and optimisation approaches with digital detectors.
   

Workpackage description

New detectors for digital imaging raise various scientific questions. They are characterised by a large amount of image pre-processing before the data is then subject to image enhancement. Moreover, these detectors have an energy dependant response, which is different to current detectors. This means that optimisation and dose reduction strategies will vary with tube potential and tube filtration in a manner unlike current detectors. Thus difficult to predict in advance. It will therefore be necessary to undertake a literature review of the technical properties of these detectors, as an initial step in establishing an optimisation strategy for exposure parameters. Theoretical approaches will be investigated as a method of predicting optional performance.

The changed energy dependence will also affect image contrast and image quality criteria. Quality criteria will therefore be reviewed in a series of consensus meetings with clinical partners in Europe using a standard set of images.

A literature review of pre and post processing algorithms will be undertaken. This will direct the work into the optimisation of post processing and the quality control of procedures to be undertaken on images not post processed. Post-processing optimisation will be undertaken using a standard set of images. Each image will be subject to different post processing algorithms, with the objective of establishing the best algorithm for a particular set of circumstances.

As new digital detectors have various computer programmes which automatically correct for deterioration in various aspects of performance, it is necessary to perform routine quality control. The quality control procedures must be robust enough to detect these changes in performance. Given the nature of the quality control task, it is vital that it is automated. Thus a computer programme for the automatic evaluation of phantom images already developed will be used to assess the performance of these systems. Images from these systems will be acquired and stored in the DICOM industry standard. Osiris software, widely available on the internet will be used on a PC, the data files will be analysed using image quality assessment algorithms which are portable and have been successfully used on images acquired using other digital detectors. Thus the application described is transposing work successfully completed in the area to be applied to new direct digital detectors. This is an extension of current practice.

A three dose level imaging strategy will be adapted using a consensus approach for the use with new digital detectors. This will be the subject of consensus trials in many European Countries, from which a common European strategy will be developed. A similar approach will be used in dentistry. Consensus on nuclear medicine issues will be achieved via expert groups.

At the end of the project a European consensus conference on Quality and dose management in digital radiology will be organised.

Collation of surveys of functional performance and patient doses with respect to computed radiography, digital radiology and nuclear medicine will be undertaken. This will input into the standardisation activities in workpackage 1.