HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Stoel, B. C. Articles by Stolk, J. Search for Related Content PubMed PubMed Citation Articles by Stoel, B. C. Articles by Stolk, J.

Quality Control in Longitudinal Studies with Computed Tomographic Densitometry of the Lungs

¹ Division of Image Processing, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands; ² Medical Science, Roche Pharmaceuticals, Nutley, New Jersey; ³ Roche Pharmaceuticals, Basel, Switzerland; and ⁴ Department of Pulmonology, Leiden University Medical Center, Leiden, The Netherlands

Correspondence and requests for reprints should be addressed to Berend C. Stoel, Ph.D., Leiden University Medical Center, Albinusdreef 2, 2333 AA Leiden, The Netherlands. E-mail: b.c.stoel{at}lumc.nl

ABSTRACT

To guarantee the reliability of densitometric data in clinical trials on pulmonary emphysema a quality control procedure is presented, to prevent that a measured progression in lung density could be reflected by a gradual change in the maintenance of the computed tomographic scanner. For that purpose, a foam phantom has been developed, which mimicks the densities of emphysematous lung tissue, fixed in a sealed Perspex box. Analysis software was developed to automatically compare the density readings with a baseline reference. It was found that this quality control procedure can pick up subtle changes in the scanner of less than 1 hounsfield unit, due to changes in the X-ray tube, detectors, or reconstruction software, and can detect certain imaging artifacts. Therefore, it is recommended that this type of procedure be used to ensure the integrity of densitometric data in longitudinal studies.

Key Words: pulmonary emphysema • computed tomography • densitometry • quality control

This article has been cited by other articles:

				H. O. Coxson, J. Mayo, S. Lam, G. Santyr, G. Parraga, and D. D. Sin New and Current Clinical Imaging Techniques to Study Chronic Obstructive Pulmonary Disease Am. J. Respir. Crit. Care Med., October 1, 2009; 180(7): 588 - 597. [Abstract] [Full Text] [PDF]