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) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map 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 HighWire Citing Articles via Google Scholar Google Scholar Articles by Rezentes, P. S. Articles by Barnes, G. T. Search for Related Content PubMed PubMed Citation Articles by Rezentes, P. S. Articles by Barnes, G. T.

Mammography Grid Performance

¹ Department of Radiology, University of Alabama Hospital and Clinics, 619 S 19th St, Birmingham, AL 35233 (P.S.R., G.T.B.)
² Faculty of Physical Sciences, Universidade de Sao Paulo, Campus de Ribeirao Preto, Brasil (A.d.A.).

PURPOSE: To measure directly the grid performance of mammography units for the range of breast thicknesses and x-ray tube potentials encountered in clinical practice.

MATERIALS AND METHODS: Contrast improvement factors and Bucky factors were determined for four mammographic units as a function of x-ray tube potential (25, 30, and 35 kVp), phantom thickness (2, 4, and 8 cm) and, on one unit, three target-filter combinations. Three units used a linear grid; one, a cellular grid. Two methods were used for nongrid measurements.

RESULTS: For all units tested, contrast improvement factor increased with increased phantom thickness and with increased kilovolt peak level for the 8-cm-thick phantom and changed little with kilovolt peak level for 2- and 4-cm-thick phantoms. At 25 and 30 kVp, contrast improvement factor performance with the linear grids was comparable; with the cellular grid, it was 5%–10% higher. In all cases, the Bucky factor increased with increased phantom thickness and decreased with increased tube potential.

CONCLUSION: Differences in grid performance exist. At 25 and 30 kVp, the cellular grid exhibited superior contrast improvement factor performance, whereas one of the linear grids exhibited superior Bucky factor performance. Measured contrast improvement and Bucky factors are dependent on nongrid technique. Cassette tunnels introduce scatter and should not be used with nongrid or magnification techniques.

Index terms: Breast radiography, quality assurance, 00.11 • Breast radiography, technology, 00.11

This article has been cited by other articles:

				J. M. Boone, J. A. Seibert, C.-M. Tang, and S. M. Lane Grid and Slot Scan Scatter Reduction in Mammography: Comparison by Using Monte Carlo Techniques Radiology, February 1, 2002; 222(2): 519 - 527. [Abstract] [Full Text] [PDF]