Abstract：
:The radiation dose to the lungs from 133Xe in lung air is directly proportional to the time integral of 133Xe concentration; i.e., the cumulated concentration in the lungs. Using kinetic models developed to fit clinical observations, we have studied the effect of retention on cumulated concentration in lung air. The models studied were (1) equal exponential washin and washout rate constants, (2) unequal exponential washin and washout rate constants, and (3) single-compartment washin and two-compartment washout. Our results show that the radiation dose varies greatly with the model chosen. A simplified method for calculating the average dose to the lungs from activity in lung air is presented. Although we have applied this method only to studies where xenon is rebreathed at constant volume and then washed out, the technique can be adapted to other protocols.
journal_name
Med Physjournal_title
Medical physicsauthors
Watson EE,Cloutier RJdoi
10.1118/1.594341subject
Has Abstractpub_date
1977-11-01 00:00:00pages
521-3issue
6eissn
0094-2405issn
2473-4209journal_volume
4pub_type
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