Summary: | 碩士 === 中臺科技大學 === 醫學影像暨放射科學系暨研究所 === 105 === X-ray examination has been playing an important role to detect early lesion for centuries, the unwanted radiation irritates to patient and relatives is much concerned. The purpose of this study focused on the detection of unwanted radiation by using TLD-100H to record the space radiation distribution.
80 TLD-100H (Harshaw, USA) were allocated in the matrix of space of 140×180 cm², 20 cm each. A LUNGMAN (Kyoto Kagaku, Japan) chest phantom were radiographed 20 times by X-ray machine (Shimadzu, Japan) with 110 kVp, 3.2 mAs, FOV set at 40×40 cm², SID at 100 cm, All data were calculated by Excel software with descriptive analysis.
The results depicted the average of primary beam of X-ray to the phantom was 1545.10 μԌy, and that of surround radiation dose was 25.11 μԌy, the average of scatter radiation at cathode side was197.15 μԌy, and that of 81.07 μԌy at anode one, background radiation dose was detected of 2.98 μԌy.
The study suggests that the radiation dose other than primary bean was lower and obviously directional. It shows the heel effect plays an important role of radiation distribution at exposure. The study also receives the highest average scatter radiation dose at the point of 50cm away from examination table, it gradually decreased of center of primary beam were also observed.
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