- 期刊
不同體重男性的心臟電腦斷層之有效劑量評估
Effective Dose Evaluation for Males of Different Weights with Cardio Examination Undergoing Computed Tomography
摘要
已知男性受檢者在進行心臟電腦斷層掃描時，尚未量測出不同體重所受到的輻射劑量。利用侖道假體(Rando phantom)與參考ICRU-48號報告，設計出10、30、50、70及90公斤的自研數學假體(self-developed mathematic phantom, SDM)，並利用中山醫學大學附設醫院的Philips PET/CT掃描儀，將變因固定於120kVp、600mAs、30mA及每片1mm的厚度條件下進行掃描，在假體內置入熱發光劑量計(thermoluminescent dosimety, TLD)，當為量測各個器官及組織所受的輻射劑量，再利用ICRP-60號報告的各器官加權因子，計算出不同公斤數下的男性受檢者，進行心臟電腦斷層檢查時所受到的全身有效劑量，此實驗結果，得到劑量在7.04到28.61mSv間，而且劑量隨著體重的增加而減低。此外，我們也得到一個指數函數方程式，藉以推演散射劑量於假體中心之劑量最高點與距離的關係。最後可以得到男性受檢者進行心臟電腦斷層掃描時，所受到的輻射劑量與體重的關係，並評估出受檢者的鄰近器官致癌風險，提供主管機關輻射評估的卓參。
並列摘要
A reliable system is yet to be established for making effective dose assessments for cardiac examination of male patients of different weights undergoing computed tomography (CT) examination. A method has been developed to correlate the effective dose-body weight relations via Rando and self-developed mathematic phantom (SDM) 90, 70, 50, 30, and 10 kg, which were derived from ICRU-48. All scans were carried out on the Philips machine with a setting of 120 kVp, 600 mAs, 30mA per slice and 1 mm slice width. Doses were measured in the organs and tissues of interest by using thermoluminescent dosemeters (TLDs). Effective doses were calculated by ICRP Publication 60. This result indicated effective doses of rando and SDM ranged from 7.04 to 28.61 mSv and decreased with the body weight. In additional, best fit lines of exponential equations were used to mold the secondary radiation as a function of distance from central axis of these phantoms. A simple equation could be used to derive relationship of effective dose and body weight of cardiac CT examination of male patients to which advisory for radiation protection can be assessed at Taiwan.