Abstract：
:Luminance scatter fractions were measured for patients and phantoms in various regions of the chest film. Scatter fractions were found to be highly variable, being quite high in the regions of the chest with a large equivalent tissue thickness (e.g. mediastinum, chest wall, and subdiaphragmatic areas). For example, approximately 90% of the radiation reaching the mediastinum region of the chest film was found to be scattered radiation when a grid was not used. Even with a 12:1 grid, less than 50% of the available primary beam contrast was being displayed in the mediastinum. In regions of the chest film with high scatter fractions, film latitude was also a problem, further reducing image contrast in these regions. Image contrast and scatter fractions in chest radiography were investigated for different scatter rejection techniques including air gaps, antiscatter grids, and slit radiography.
journal_name
Med Physjournal_title
Medical physicsauthors
Niklason LT,Sorenson JA,Nelson JAdoi
10.1118/1.595027subject
Has Abstractpub_date
1981-09-01 00:00:00pages
677-81issue
5eissn
0094-2405issn
2473-4209journal_volume
8pub_type
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