Abstract:
:Computer tomographic (CT) scans are used to correct for tissue inhomogeneities in radiotherapy treatment planning. In order to guarantee a precise treatment, it is important to obtain the relationship between CT Hounsfield units and electron densities (or proton stopping powers for proton radiotherapy), which is the basic input for radiotherapy planning systems which consider tissue heterogeneities. A method is described to determine improved CT calibrations for biological tissue (a stoichiometric calibration) based on measurements using tissue equivalent materials. The precision of this stoichiometric calibration and the more usual tissue substitute calibration is determined by a comparison of calculated proton radiographic images based on these calibrations and measured radiographs of a biological sample. It has been found that the stoichiometric calibration is more precise than the tissue substitute calibration.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Schneider U,Pedroni E,Lomax Adoi
10.1088/0031-9155/41/1/009subject
Has Abstractpub_date
1996-01-01 00:00:00pages
111-24issue
1eissn
0031-9155issn
1361-6560journal_volume
41pub_type
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