Plymouth Hospitals NHS Trust, Derriford Hospital, Plymouth, Devon, UK.
Clin Radiol. 2010 Dec;65(12):1013-7. doi: 10.1016/j.crad.2010.08.001. Epub 2010 Sep 29.
To calculate the effective dose from cardiac multidetector computed tomography (MDCT) using a computer-based model utilizing the latest International Commission on Radiation Protection (ICRP) 103 tissue-weighting factors (2007), to compare this dose with those calculated with previously published chest conversion factors and to produce a conversion factor specific for cardiac MDCT.
An observational study of 152 patients attending for cardiac MDCT as part of their usual clinical care in a university teaching hospital. The dose for each examination was calculated using the computer-based anthropomorphic ImPACT model (the imaging performance assessment of CT scanners) and this was compared with the dose derived from the dose-length product (DLP) and a chest conversion factor.
The median effective dose calculated using the ImPACT calculator (4.5 mSv) was significantly higher than the doses calculated with the chest conversion factors (2.2-3 mSv).
The use of chest conversion factors significantly underestimates the effective dose when compared to the dose calculated using the ImPACT calculator. A conversion factor of 0.028 would give a better estimation of the effective dose from prospectively gated cardiac MDCT.
利用基于计算机的模型，使用最新的国际辐射防护委员会（ICRP）103 组织权重因子（2007 年）计算心脏多排螺旋 CT（MDCT）的有效剂量，将该剂量与之前发表的胸部转换因子计算的剂量进行比较，并生成心脏 MDCT 的专用转换因子。
这是一项在大学教学医院进行的 152 例接受心脏 MDCT 检查的患者的观察性研究。使用基于计算机的人体形态学 ImPACT 模型（CT 扫描仪的成像性能评估）计算每次检查的剂量，并将其与剂量长度乘积（DLP）和胸部转换因子计算的剂量进行比较。
使用 ImPACT 计算器计算的中位数有效剂量（4.5 mSv）明显高于胸部转换因子计算的剂量（2.2-3 mSv）。
与使用 ImPACT 计算器计算的剂量相比，胸部转换因子的使用会显著低估有效剂量。对于前瞻性门控心脏 MDCT，转换因子 0.028 可以更好地估计有效剂量。
