Karlo Christoph, Gnannt Ralph, Frauenfelder Thomas, Leschka Sebastian, Brüesch Martin, Wanner Guido A, Alkadhi Hatem
Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, 8091, Zurich, Switzerland.
Emerg Radiol. 2011 Aug;18(4):285-93. doi: 10.1007/s10140-011-0948-5. Epub 2011 Apr 7.
The purpose of this study is to assess the influence of different arm positioning techniques on thoracic and abdominal image quality and radiation dose of whole-body trauma CT (wbCT). One hundred and fifty polytrauma patients (104 male, mean age 47 ± 19) underwent wbCT with arms elevated above the head (group A, n=50), alongside the abdomen (group B, n=50), and on a pillow ventrally to the chest with both arms flexed (group C, n=50). Two blinded, independent observers measured image noise and rated image quality (scores 1-3) of the liver, aorta, spleen, spine, and lower lungs. Radiation dose parameters were noted, and the abdomens' anterior-posterior diameter and scan lengths were measured. Interreader agreements for image noise (r=0.86; p<0.001) and subjective image quality (k=0.71-0.84) were good. Noise was lower (p<0.05), image quality of the liver, aorta, spleen, and spine was higher, and radiation dose lower in group A than in groups B and C (p<0.001, each). Image quality of the spleen, liver, and aorta were higher in group C than in group B (p<0.05, each). No significant differences in scan length (p=0.61) were found among groups. Abdominal anterior-posterior diameter correlated significantly with noise (r=0.82; p<0.01) and dose (r=0.47; p<0.001). Estimated effective radiation doses were significantly (p<0.001) higher in groups B (21.2 mSv) and C (21.9 mSv) as compared to A (16.1 mSv). In wbCT for polytrauma patients, positioning of the arms above the head results in better image quality and lower radiation dose. Placing the flexed arms on a large pillow ventrally to the chest significantly improves image quality as compared to positioning alongside the abdomen.
本研究的目的是评估不同的手臂摆放技术对全身创伤CT（wbCT）胸部和腹部图像质量及辐射剂量的影响。150例多发伤患者（104例男性，平均年龄47±19岁）接受了wbCT检查，其中手臂举过头顶的为A组（n = 50），手臂放在腹部两侧的为B组（n = 50），双臂弯曲放在胸前枕头上的为C组（n = 50）。两名盲法、独立的观察者测量了图像噪声，并对肝脏、主动脉、脾脏、脊柱和下肺的图像质量进行评分（1 - 3分）。记录辐射剂量参数，并测量腹部前后径和扫描长度。观察者间对图像噪声（r = 0.86；p < 0.001）和主观图像质量（k = 0.71 - 0.84）的一致性良好。A组的噪声更低（p < 0.05），肝脏、主动脉、脾脏和脊柱的图像质量更高，辐射剂量低于B组和C组（均p < 0.001）。C组脾脏、肝脏和主动脉的图像质量高于B组（均p < 0.05）。各组间扫描长度无显著差异（p = 0.61）。腹部前后径与噪声（r = 0.82；p < 0.01）和剂量（r = 0.47；p < 0.001）显著相关。与A组（16.1 mSv）相比，B组（21.2 mSv）和C组（21.9 mSv）估算的有效辐射剂量显著更高（p < 0.00）。在多发伤患者的wbCT检查中，将手臂举过头顶可获得更好的图像质量和更低的辐射剂量。与将手臂放在腹部两侧相比，将弯曲的手臂放在胸前大枕头上可显著提高图像质量。
