Shah Mudasir Ashraf, Ahmad Mehtab, Khalid Saifullah, Qaseem Syed M Danish, Siddiqui Shaista, Talib Sayema, Rather Sajad Ahmed, Firdous Arfat
Department of Radiodiagnosis, Faculty of Medicine, Jawaharlal Nehru Medical College, Aligarh Muslim University, Aligarh, Uttar Pradesh, India.
Department of Radiological Physics and Bio-Engineering, Sher-i-Kashmir Institute of Medical Sciences, Srinagar, India.
J Med Phys. 2023 Apr-Jun;48(2):210-218. doi: 10.4103/jmp.jmp_102_22. Epub 2023 Jun 29.
The study aimed to compute the effective dose (E) and size-specific dose estimate (SSDE) of routine adult patients undergoing thorax and abdominal computed tomography (CT) imaging and to present their multivariate analysis. All adult thorax and abdominal CT examinations conducted from March 2022 to June 2022 were prospectively included in this study. The Water Equivalent Diameter () and SSDE of all the examinations were computed from CT dose index volume () and Dose length product (DLP) displayed on the dose report in the CT console. The multivariate statistical analysis was performed to investigate the correlation of SSDE and E on , area of the region of interest (ROI) (), body mass index (BMI), conversion factor ( and hounsfield () number in the ROI at 95% level of significance ( 0.05). The linear regression analysis was performed to investigate the dependence of SSDE and E on other parameters for both abdominal and thorax patients. A total number of 135 (Abdomen = 61 and Thorax = 74) measurements were performed. The mean value of effective dose for abdomen and thorax patients was found to be 7.17 ± 3.94 and 4.89 ± 2.16 , respectively. The SSDE was observed to be 13.24 ± 3.61 and 13.04 ± 3.61 for thorax and abdomen respectively. The multivariate analysis suggests that SSDE for abdominal CT is found significantly dependent on , and with 0.05 and E is found to be significantly dependent on DLP, , and at 95% level of confidence for abdominal CT imaging. SSDE for thorax CT was found significantly dependent on BMI, , , and at 95% level of confidence. Furthermore, E was observed dependent on DLP at 0.05. The linear regression analysis also shows that E is strongly correlated with DLP ( = 1.0) for both thorax and abdominal CT, further the SSDE was observed strongly correlated with with = 0.79 and = 0.86 for abdomen and thorax CT respectively. A strong correlation was observed between BMI and for abdominal CT imaging ( = 0.68). The mean value of SSDE for thorax is slightly greater than abdomen. The average value of effective dose for abdomen and thorax measurements was found to be 7.17 ± 3.94 and 4.89 ± 2.16 and , correspondingly. SSDE for both abdomen and thorax CT is significantly dependent on , and at 95% level of confidence. The strong correlation was also observed E on DLP and SSDE on for both Abdomen and Thorax CT. The strong dependence of on BMI ( = 0.68) is due to the excessive fat concentration around the stomach and abdomen.
本研究旨在计算接受胸部和腹部计算机断层扫描（CT）成像的成年患者的有效剂量（E）和尺寸特异性剂量估计值（SSDE），并进行多因素分析。2022年3月至2022年6月期间进行的所有成年胸部和腹部CT检查均前瞻性纳入本研究。所有检查的水等效直径（）和SSDE均根据CT控制台剂量报告中显示的CT剂量指数容积（）和剂量长度乘积（DLP）计算得出。进行多因素统计分析，以研究SSDE和E与、感兴趣区域（ROI）面积（）、体重指数（BMI）、转换因子（）以及ROI处95%显著性水平（0.05）的亨氏（）值之间的相关性。进行线性回归分析，以研究腹部和胸部患者中SSDE和E对其他参数的依赖性。共进行了135次测量（腹部=61次，胸部=74次）。发现腹部和胸部患者的有效剂量平均值分别为7.17±3.94和4.89±2.16。观察到胸部和腹部的SSDE分别为13.24±3.61和13.04±3.61。多因素分析表明，腹部CT的SSDE在95%置信水平下显著依赖于、和，且E在95%置信水平下显著依赖于DLP、、和。胸部CT的SSDE在95%置信水平下显著依赖于BMI、、、和。此外，在0.05时观察到E依赖于DLP。线性回归分析还表明，胸部和腹部CT的E均与DLP密切相关（=1.0），进一步观察到腹部和胸部CT的SSDE分别与密切相关，=0.79和=0.86。在腹部CT成像中观察到BMI与之间存在强相关性（=0.68）。胸部的SSDE平均值略高于腹部。腹部和胸部测量的有效剂量平均值分别为7.17±3.94和4.89±2.16。腹部和胸部CT的SSDE在95%置信水平下均显著依赖于、和。在腹部和胸部CT中还观察到E与DLP以及SSDE与之间存在强相关性。对BMI的强烈依赖性（=0.68）是由于胃和腹部周围脂肪浓度过高。
