Abstract：
PURPOSE:To evaluate a model which can predict patient's Entrance Skin Exposure (ESE) from height and weight and a single kVp mR/mAs measurement for radiographic. METHODS:Patient height, weight and post exposure mAs are obtained to assess ESE based on IAEA model. Patient's thickness is obtained by assuming a cylindrical geometry. The validity of this assumption is tested against actual measurements. Source to Skin Distance (SSD) is computed from patient's thickness and the Source-Image receptor Distance (SID) used during exposure. Entrance Skin Exposure is calculated as a product of post exposure mAs and a single 80 kVp mR/mAs obtained at a reference distance corrected inversely for SSD. Values of mR/mAs at other kVp's are obtained by quadratic variation of output with kVp. RESULTS:The validity of predicting patient thickness will be presented based on numerous measurements performed on test subjects. Deviation between the ESE values using of single kVp, mR/mAs measurement and the ones obtained by the conventional multiple kVp mR/mAs will be presented as well. CONCLUSIONS:This work indicates a simple approach to determine the patient's ESE based on the patient's height and weight for radiographic units, which will be very useful for institutions that do not have a dedicated physicist.
journal_name
Med Physjournal_title
Medical physicsauthors
Maricle S,Jeutang L,Prasad Gdoi
10.1118/1.4734825subject
Has Abstractpub_date
2012-06-01 00:00:00pages
3650issue
6Part5eissn
0094-2405issn
2473-4209journal_volume
39pub_type
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