Radiology, Vol 194, 407-412, Copyright © 1995 by Radiological Society of North America
Clinical evaluation of pulmonary nodules with single-exposure dual- energy subtraction chest radiography with an iterative noise-reduction algorithm
S Kido, J Ikezoe, H Naito, J Arisawa, S Tamura, T Kozuka, W Ito, K Shimura and H Kato
Department of Radiology, Osaka University Medical School, Japan.
PURPOSE: To compare the clinical usefulness of the single-exposure dual-
energy subtraction method with an iterative noise-reduction algorithm.
MATERIALS AND METHODS: Fourteen radiologists read three sets of images from
44 patients: original computed radiographic images only, original computed
radiographic images plus conventional bone-subtracted images, and original
computed radiographic images plus iterative noise-reduced bone-subtracted
images. Twenty-two patients had one or more (maximum, five) pulmonary
nodules; 22 had no pulmonary nodules. Observer performance was evaluated by
means of calculation of the average area under the alternative
free-response receiver operating characteristic curves (A1). RESULTS:
Compared with the original computed radiographic image only, detection of
nodules was significantly better with both the original computed
radiographic image plus iterative bone-subtracted image (A1 = 0.72 +/- 0.02
and 0.66 +/- 0.02, respectively; P = .01) and the original computed
radiographic image plus conventional bone- subtracted image (A1 = 0.66 +/-
0.02 and 0.61 +/- 0.01, respectively; P = .03). CONCLUSION: The iterative
noise-reduction algorithm is superior to conventional methods in detection
of pulmonary nodules.
