![]() Download AlongAway.prc |
PalmOS PDA Applications: Along & AwayAnother popular basis for brachytherapy QA are the Greenfield-Tichman-Norman (GTN) linear source implant tables (Greenfield MA, Tichman M and Norman A, Dosage tables for linear radium sources filtered by 0.5 and 1.0 mm of platinum. Radiology 1959; 73:418). It is common for the original tables to be modified to yield cGy/milligram-hour by dividing the original values by the factor C = 0.84 / (0.825 * 0.957) = 1.064 which corrects for the alteration of Γ for radium and converts exposure to dose to tissue. The tables can be adapted for HDR use by converting the original values to a more convenient form for Ir-192 (Γ = 0.469) HDR by dividing the original values by C and then again by HGTN = (3600 * 0.825 / 0.469) = 6333 to yield cGy/mCi-sec. The HDR dwell time in seconds is calculated by dividing the tabulated cGy/mCi-sec values by the prescribed dose (in cGy) and multiplying by the current activity of the source (in mCi). Note: The reciprocal (ie mCi-sec/cGy) is actually displayed in this calculator to be consistent with the Paterson-Parker based companion application for linear sources. Click here to download the .zip archive: Along & Away 1.0.0 (20K), last updated 9/16/03. Download: AlongAway.prc.zip (16K)
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