低劑量胸部電腦斷層檢查劑量與身體參數相關性探討

Investigation of the relationship between chest low-dose computed tomography dose and body parameters

張書妤(Shu-Yu Chang)

指導教授 ： 黎俊蔚

高雄醫學大學/健康科學院/醫學影像暨放射科學系碩士在職專班/碩士(2020年)

摘要

背景與目的
當低劑量胸部電腦斷層（low-dose chest computed tomography ,LDCT）已成為普遍性檢查時，需要注意輻射暴露是否適當合宜，目前國內LDCT建議輻射劑量基準與國外相同為3 mGy，但有研究指出LDCT輻射劑量上限3 mGy可能不適用於韓國人。本次研究目的是探討LDCT輻射劑量與身體參數相關性。

材料與方法
108年01月至06月共收集到1046筆LDCT資料，使用SPSS軟體依年齡、身高、體重、身體質量指數(body mass index ,BMI)、容積電腦斷層劑量指數(volume computed tomography dose index ,CTDIvol)及劑量長度乘積(dose-length product ,DLP)、體型特異劑量評估（Size-specific dose estimate，SSDE）、體型直徑等數值進行敘述性統計及皮爾森相關係數分析。

研究結果
LDCT檢查的CTDIvol與BMI及體重呈現良好相關性，r值分別為0.871 ( p<0.001)及0.910 ( p<0.001)； DLP與BMI及體重也是呈現良好相關性，r值分別為0.833 ( p<0.001)及0.932 ( p<0.001)， CTDIvol為0.67±0.30 mGy(範圍:0.2-2.0)，低於LDCT建議輻射劑量基準3 mGy；男性的SSDE高於女性，男性的平均體型直徑轉換因子小於女性；在支氣管分岔(tracheal bifurcation)與中間肝(mid-liver)的體型直徑前後+側位與 CTDIvol呈現高度相關性，r值分別為0.879( p<0.001)及0.905( p<0.001)。

討論與結論
本研究的LDCT的CTDIvol為0.67±0.30 mGy，均低於建議輻射劑量基準3 mGy； CTDIvol及DLP會與受檢者BMI、體重與體型直徑呈現高度相關性； CTDIvol與SSDE呈現高度相關性；全部群體的SSDE均高於CTDIvol，表示國人的體型相對偏小，應該採用與國外不同的輻射劑量基準，在未來需要進一步的研究來建立適用於國人的LDCT輻射劑量基準。

關鍵字

低劑量胸部電腦斷層 ； 輻射劑量

並列摘要

Background and Ojective
When low-dose chest computed tomography (LDCT) has become a common examination, it is necessary to pay attention to whether the radiation exposure is appropriate.The current domestic LDCT recommended radiation dose benchmark is 3 mGy, the same as abroad.The studies have pointed out that the upper limit of LDCT radiation dose of 3 mGy may not be suitable for Koreans.The purpose of this study is to explore the correlation between LDCT radiation dose and physical parameters.

Materials and Methods
A total of 1,046 low-dose chest computed tomography data were collected from January to June 108, and SPSS software was used to make statistics based on age, height, weight, BMI, volume computed tomography dose index and dose length product, Size-specific dose estimate, and body size diameter analysis.

Results
The CTDIvol of LDCT examination showed good correlation with BMI and body weight, with r values of 0.871 (p<0.001) and 0.910 (p<0.001).DLP also showed a good correlation with BMI and body weight, with r values of 0.833 (p<0.001) and 0.932 (p<0.001).CTDIvoll is 0.67±0.30 mGy (range: 0.2-2.0), which is 3 mGy lower than the recommended radiation dose benchmark of LDCT.The SSDE of men is higher than that of women, and the average body size conversion factor of men is smaller than that of women.In tracheal bifurcation and mid-liver, the anteroposterior and lateral body diameters were highly correlated with CTDIvol, with r values of 0.879 (p<0.001) and 0.905 (p<0.001).

Conclusion
The CTDIvol of the LDCT in this study is 0.67±0.30 mGy, which was lower than the recommended radiation dose benchmark of 3 mGy,CTDIvol and DLP will be highly correlated with the subject's BMI, body weight and body diameter.CTDIvol and SSDE are highly correlated.The SSDE of all groups is higher than CTDIvol, indicating that Taiwanese people are relatively small and should adopt a different radiation dose benchmark from abroad.In the future, further research is needed to establish LDCT radiation dose benchmarks applicable to Taiwanese people.

並列關鍵字

LDCT ； CTDIvol ； SSDE

參考文獻

參考文獻

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