Congress:
EuroSafe Imaging 2017
Keywords:
Radiation safety, Digital radiography, CT, Cone beam CT, Radioprotection / Radiation dose, Action 5 - Performance indicators for radiation protection management, Action 9 - Facilitation of research in advanced topics of radiation protection, Action 2 - Clinical diagnostic reference levels (DRLs), Action 9 - Development of criteria for safe imaging procedures, Action 7 - Medical radiation protection research: MELODI, EURAMED, Action 3 - Optimisation, diagnostic reference levels, image quality, Technical aspects, Education and training, Quality assurance
Authors:
W. Stiller, R. W. Loose, C. Hoeschen, K. Katsari, L. Oleaga Zufiría, D. Tsetis, C. Granata, S. Schindera, J. Damilakis, D. Tack, L. Rainford
DOI:
10.1594/esi2017/ESI-0054
Background/Introduction
In clinical routine,
different imaging tasks require different levels of quality: Images of the highest quality are not essential for all diagnostic tasks.
Instead,
the level of image quality needed (e.g.
good low-contrast discernibility at low noise levels,
or high spatial resolution accepting an increased noise level) is dependent on the clinical task,
i.e.
it should be based on the indication as well as on the individual patient characteristics [2].
For imaging modalities relying on the use of ionizing radiation such as computed tomography (CT),
correct selection of the image quality “appropriate” for each specific diagnostic task will thus result in an optimum use of radiation and in a reduction of exposure to ionizing radiation for most patients [2].
Definitions of diagnostic indication-based “appropriate image quality” should be driven by the clinicians’ requirements of everyday clinical routine and needs input from the radiologists’ community by subspecialty.
Determining the image quality “appropriate” for a certain diagnostic purpose is a complex task,
as both quantitative metrics (e.g.
noise,
spatial resolution,
etc.) and qualitative observer perceptions (fine structure discernibility and low-contrast detail detectability) are involved and need to linked to each other[2].
As part of the EuroSafe Imaging campaign,
which is the flagship radiation protection initiative of the ESR launched in 2014,
its Appropriate Image Quality subgroup aims at a definition of indication-based “appropriate image quality” by a panel of experts for those CT examinations deemed to be clinically most relevant (“relevant exams”).
To this end,
the group is working toward the identification of adequate standardized criteria for judging the “appropriateness” of image quality for a certain CT imaging task in view of diagnostic confidence.
The definition of indication-based “appropriate image quality” enabling reliable and reproducible diagnosis with regard to each specific diagnostic question encountered in clinical routine should be based on standardized quality criteria arising from clinicians’ requirements by subspecialty.
Therefore,
after having identified the clinically most relevant CT examinations by indication and subspecialty,
it is foreseen to define qualitative image quality criteria for these clinical indications by expert consensus.
Based on these qualitative criteria derived from clinical practice,
measurable quantitative metrics for assessing indication-based image quality will be sought and linked to the clinical criteria.