Source Image Distance 변화에 따른 환자 및 검사자의 피폭선량 비교

In Comparison With Entrance Surface Dose of Patients and Operators With Changing SID

Purpose : We suggest the basic data that we set up the standard SID without changing image quality, by comparing the exposure dose of patients and operators with SID, in fluoroscopy. Materials and Methods : Shimavision 3200HG (Shimaclzu, over tube system) was used for fluoroscopy. Unfors Xi meter(dosimetry), CDRH phantom and Rando phantom were used to measure image as human equivalence. We assess average patient exposure dose and image contrast acquired 10 spots and 10sec of fluoroscopies 10times by changing SID(1000mm, 1100mm, 1200mm, 1300mm). In addition, We measured operator’s dose at point(chest1200mm, thyroid1400mm, lens1600mm) from machine table in same method. Results : The measured results are as follows 1. The longer the SID, the less exposure dose in fluoroscopy and spot. - Fluoroscopy : 1000mm 319.3μGy/s, 1100mm 276.7μGy/s, 1200mm 235.3μGy/s, 1300 203.6μGy/s - Spot : 1000mm 36.9mGy/s, 1100mm 29.3mGy/s, 1200mm 25.5mGy/s, 1300 21.7mGy/s 2. It was the least operator’s exposure dose at chest(1300mm, 1.15μGy/s), otherwise, it was the much at 1000mm (1.38μGy/s). It was the least at thyroid and lens, otherwise, it was the much at 1000mm. 3. AS the result of image quality assessment by using CDRH phantom, It was evaluated in appropriately at SID 1300mm. Conclusion : We suggest that SID was setted up 1200mm. Because it is effectively distance that it is not only a falling-off in image quality but less exposure dose of patients and operators.