Dose compensation of the total body irradiation therapy

The aim of the study is to improve dose uniformity in the body by the compe nsator-rice and to decrease the dose to the lung by the partial lung block. Rando phantom supine was set up to treat bilateral fields with a 15 MV lin ear accelerator at 415 cm treatment distance. The experimental procedure in cluded three parts. The first part was the bilateral irradiation without ri ce compensator, and the second part was with rice compensator. In the third part, rice compensator and partial lung block were both used. The results of thermoluminescent dosimeters measurements indicated that without rice co mpensator the dose was non-uniform. Contrarily, the average dose homogeneit y with rice compensator was measured within +/-5%, except for the thorax re gion. Partial lung block can reduce the dose which the lung received. This is a simple method to improve the dose homogeneity and to reduce the lung d ose received. The compensator-rice is cheap, and acrylic boxes are easy to obtain. Therefore, this technique is suitable for more studies. (C) 2001 El sevier Science Ltd. All rights reserved.