Abstract:
:A computerized system for monitoring dose-area product (DAP) has been developed for region of interest (ROI) fluoroscopy in which patient exposure is reduced using an x-ray attenuating filter with an aperture. The system includes an IBM compatible computer which is connected through an IEEE-488 interface to an electrometer which measures the charge from a DAP ionization chamber. A digital input/output board connects the computer to the filter placement device to determine whether the filter is in or out of the beam, and to the x-ray generator to determine when the exposure is due to spot filming. The computer logs the DAP from conventional fluoroscopy, ROI fluoroscopy and spot filming separately, applying the appropriate calibration factor for each. Measured DAPs, fluoroscopic DAP rates and exposure times are displayed in real-time. The system has been installed in a GI fluoroscopic room so that the dose-reduction potential of ROI imaging can be evaluated.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Kezerashvili M,Bednarek DR,Rudin Sdoi
10.1088/0031-9155/42/4/001subject
Has Abstractpub_date
1997-04-01 00:00:00pages
613-23issue
4eissn
0031-9155issn
1361-6560journal_volume
42pub_type
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