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

This Article Figures Only Full Text Full Text (PDF) All Versions of this Article: 2222010491v1 222/2/519    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend 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 Google Scholar Google Scholar Articles by Boone, J. M. Articles by Lane, S. M. Search for Related Content PubMed PubMed Citation Articles by Boone, J. M. Articles by Lane, S. M.

Grid and Slot Scan Scatter Reduction in Mammography: Comparison by Using Monte Carlo Techniques¹

¹ From the Department of Radiology, University of California, Davis, 4701 X St, Research Imaging Laboratory, UC Davis Medical Center, Sacramento, CA 95817 (J.M.B., J.A.S.); Creatv Microtech, Inc, Potomac, Md (C.M.T.); and Lawrence Livermore National Laboratory, Livermore, Calif (S.M.L.). Received February 20, 2001; revision requested April 11; revision received June 15; accepted June 22. Supported in part by grant 1RB-0192 from the California Breast Cancer Research Program and by National Institutes of Health (NIH) grant R21 CA 82077 for support of the techniques discussed herein as they are relevant to low-kV computed tomography of a specimen; C.M.T. supported in part by grant R43-CA76752 from the NIH for the development of novel grid technology. Address correspondence to J.M.B. (e-mail: jmboone@ucdavis.edu).

PURPOSE: To evaluate a comprehensive array of scatter cleanup techniques in mammography by using a consistent methodology.

MATERIALS AND METHODS: Monte Carlo techniques were used to evaluate the Bucky factor (BF) and the contrast improvement factor (CIF) for linear and cellular grids and for slot scan and scanning multiple-slot assembly (SMSA) systems.

RESULTS: For a 28-kVp molybdenum anode–molybdenum filter spectrum with a standard detector and a 6-cm-thick 50% adipose–50% glandular breast phantom, slot scan techniques delivered an ideal BF. For slot widths greater than 4 mm, however, the CIF was lower than that achieved by the high-transmission cellular grid with a grid ratio of 3.8:1. A tungsten-septa air-interspaced cellular grid with a 4:1 grid ratio outperformed the high-transmission cellular grid in both BF and CIF. The SMSA was shown to be efficacious when 4-mm-wide slots were separated by at least 20 mm. In comparison with the literature, 3.6% agreement was achieved with other Monte Carlo studies, 3.3% with an experimental study that used a digital detector, and 13%–29% agreement was demonstrated in comparison to film-based experimental studies.

CONCLUSION: With use of consistent methods for comparison, cellular grids were shown to substantially outperform linear grids but have slightly higher BFs compared with that of slot scan geometries at the same CIF.   

Index terms: Breast radiography, technology, 00.112, 00.1215 • Physics, 00.99 • Radiations, 00.99