A comparison of film, Computed Radiography (CR) hard copy and PACS soft copy images and the effect of radiation dose on contrast detail curves.

Gwyn Weatherburn

Health Economics Research Group, Brunel University,

Uxbridge, Middlesex, UB8 3PH

Glyn Davies

Department of Radiology, Glan Clwyd Hospital,

Bodelwyddan.

Clwyd, LL18 5UJ

This study was undertaken as part of an evaluation of a small Picture Archive and Communications System (PACS) linking the Radiology Department and the Intensive Therapy Unit (ITU) at Glan Clwyd Hospital and was financed by NHS Wales. 

In this hospital, the ITU clinicians viewed soft copy images in ITU and the radiologists reported the same examinations from hard copy images in Radiology.  Conventional film/screen images were used throughout the rest of the hospital.  Thus, this study aimed to compare these three types of images using standard test tools. 

Leeds test objects (not designed for use with CR and PACS systems) were used to compare film, CR hard copy and PACS images in terms of high contrast resolution, low contrast detectability, effective dynamic range and threshold contrast detail detectability.  In addition, for threshold detail detectability, the effect of increase in mAs on all three types of images was investigated.  All images were viewed and scored by four medical physicists.

The results of this study will be presented.

Correspondence:
Gwyn Weatherburn
Health Economics Research Group,
Brunel University,
Uxbridge, Middlesex, UB8 3PH, UK

Oral presentation at EuroPACS'98, Barcelona, Spain