Share Email Print

Proceedings Paper

Observer study of a noise suppression algorithm for computed radiography images
Author(s): Mary Couwenhoven; William Sehnert; Xiaohui Wang; Michael Dupin; John Wandtke M.D.; Steven Don M.D.; Richard Kraus M.D.; Narinder Paul M.D.; Neil Halin M.D.; Robert Sarno M.D.
Format Member Price Non-Member Price
PDF $17.00 $21.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Lower x-ray exposures are commonly used in radiographic exams to reduce the patient radiation dose. An unwanted side effect is that the noise level increases as the exposure level is reduced. Image enhancement techniques increasing image contrast, such as sharpening and dynamic range compression tend to increase the appearance of noise. A Gaussian filter-based noise suppression algorithm using an adaptive soft threshold has been designed to reduce the noise appearance in low-exposure images. The advantage of this technique is that the algorithm is signal-dependent, and therefore will only impact image areas with low signal-to-noise ratio. Computed radiography images captured with lower exposure levels were collected from clinical sites, and used as controls in an observer study. The noise suppression algorithm was applied to each of the control images to generate test images. Hardcopy printed film versions of control and test images were presented side-by-side on a film alternator to six radiologists. The radiologists were asked to rate the control and test images using a 9-point diagnostic quality rating scale and a 7-point delta-preference rating scale. The results showed that the algorithm reduced noise appearance, which was preferred, while preserving the diagnostic image quality. This paper describes the noise suppression algorithm and reports on the results of the observer study.

Paper Details

Date Published: 6 April 2005
PDF: 10 pages
Proc. SPIE 5749, Medical Imaging 2005: Image Perception, Observer Performance, and Technology Assessment, (6 April 2005); doi: 10.1117/12.595159
Show Author Affiliations
Mary Couwenhoven, Eastman Kodak Co. (United States)
William Sehnert, Eastman Kodak Co. (United States)
Xiaohui Wang, Eastman Kodak Co. (United States)
Michael Dupin, Eastman Kodak Co. (United States)
John Wandtke M.D., Univ. of Rochester Medical Ctr. (United States)
Steven Don M.D., Mallinckrodt Institute of Radiology (United States)
Richard Kraus M.D., Mallinckrodt Institute of Radiology (United States)
Narinder Paul M.D., Univ. of Toronto (Canada)
Neil Halin M.D., Tufts New England Medical Ctr. (United States)
Robert Sarno M.D., Tufts New England Medical Ctr. (United States)

Published in SPIE Proceedings Vol. 5749:
Medical Imaging 2005: Image Perception, Observer Performance, and Technology Assessment
Miguel P. Eckstein; Yulei Jiang, Editor(s)

© SPIE. Terms of Use
Back to Top