Abstract：
:Radiographic magnification is often employed in mammography to improve detection of small anatomical details of clinical interest, such as microcalcifications. The image size depends on the conventional magnification factor, on the focal spot size, and on the x-ray angulation. In this paper magnification effects are investigated for an object which lays off the radiation field center, for which there is a "lateral magnification" that makes it possible to obtain a sharper image of the object. This occurs because the true image size (i.e., the shadow) becomes larger as the distance from the beam center to the object increases, while the total blurring (penumbra) which is responsible for the unsharpness remains constant. The statement is valid only in the boundary of the perpendicular axis, which for most mammographic units corresponds to the position where the thickest portion of the breast is placed. Calculations are presented which show that the lateral magnification can be useful for enhancing breast microcalcifications using radiographic magnification.
journal_name
Med Physjournal_title
Medical physicsauthors
Schiabel H,Ventura A,Frère AFdoi
10.1118/1.597288subject
Has Abstractpub_date
1994-02-01 00:00:00pages
271-6issue
2eissn
0094-2405issn
2473-4209journal_volume
21pub_type
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