Purpose : Uniform dose distribution of the whole body is essential factor for the total body irradiation(TBI). In order to achieved this goal, we used to compensation filter to compensate body contour irregularity and thickness differences. But we can not compensate components of body, namely lung or bone. The purpose of this study is evaluation of dose attenuation in bone tissue when TBI using diode detectors and TLD system.
Materials and Methods : The object of this study were 5 patients who undergo TBI at our hospital. Dosimetry system were diode detectors and TLD system. Treatment method was bilateral and delivered 10MV X-ray from linear accelerator. Measurement points were head, neck, pelvis, knees and ankles. TLD used two patients and diode detectors used three patients.
Results Results : are as followed. All measured dose value were normalized skin dose. TLD dosimetry : Measured skin dose of head, neck, pelvis, knees and ankles were respectably. Measured mid-depth dose of pelvis, knees and ankles were respectably. There were dose attenuation at mid-depth in pelvis, knees and ankles. Diode detector : Measured skin dose of head, neck, pelvis, knees and ankles were respectably. There were dose attenuation at mid-depth in pelvis, knees and ankles.
Conclusion : We concluded that dose measurement with TLD or diode detector was inevitable when TBI treatment. Considered dose attenuation in bone tissue, We must have adequately deduction of compensator thickness that body portion involved bone tissue.
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