Measurement of skin entrance exposure with a dose-area-product meter at chest radiography

Skin entrance exposure measurements obtained with a dose-area-product meter and thermoluminescent dosimeters were compared at posteroanterior and lateral chest radiography in 52 adult male patients. In a linear regression analysis of data collected in both views, values of 1.23 +/- 0.02 and 1.26 +/- 0.01 (r = .98 and .99) were found fur the ratios of thermoluminescent-dosimeter and dose-area-product exposures, respectively. Skin entrance exposures from 16 mR (4.13 mu C/kg) to 150 mR (38.7 mu C/kg) in the posteroanterior view and 24 mR (6.19 mu C/kg) to 475 mR (123 mu C/kg) in the lateral view were found. Dose-area-product meters offer a rapid and accurate means to measure skin entrance exposure when the radiography field size is known.