Ho Lisa M, Nelson Rendon C, Delong David M
Department of Radiology, Duke University Medical Center, Box 3808, Durham, NC 27710, USA.
Radiology. 2007 May;243(2):431-7. doi: 10.1148/radiol.2432060390.
To prospectively evaluate the use of lean body weight (LBW) as the main determinant of the volume and rate of contrast material administration during multi-detector row computed tomography of the liver.
This HIPAA-compliant study had institutional review board approval. All patients gave written informed consent. Four protocols were compared. Standard protocol involved 125 mL of iopamidol injected at 4 mL/sec. Total body weight (TBW) protocol involved 0.7 g iodine per kilogram of TBW. Calculated LBW and measured LBW protocols involved 0.86 g of iodine per kilogram and 0.92 g of iodine per kilogram calculated or measured LBW for men and women, respectively. Injection rate used for the three experimental protocols was determined proportionally on the basis of the calculated volume of contrast material. Postcontrast attenuation measurements during portal venous phase were obtained in liver, portal vein, and aorta for each group and were summed for each patient. Patient-to-patient enhancement variability in same group was measured with Levene test. Two-tailed t test was used to compare the three experimental protocols with the standard protocol.
Data analysis was performed in 101 patients (25 or 26 patients per group), including 56 men and 45 women (mean age, 53 years). Average summed attenuation values for standard, TBW, calculated LBW, and measured LBW protocols were 419 HU +/- 50 (standard deviation), 443 HU +/- 51, 433 HU +/- 50, and 426 HU +/- 33, respectively (P = not significant for all). Levene test results for summed attenuation data for standard, TBW, calculated LBW, and measured LBW protocols were 40 +/- 29, 38 +/- 33 (P = .83), 35 +/- 35 (P = .56), and 26 +/- 19 (P = .05), respectively.
By excluding highly variable but poorly perfused adipose tissue from calculation of contrast medium dose, the measured LBW protocol may lessen patient-to-patient enhancement variability while maintaining satisfactory hepatic and vascular enhancement.
前瞻性评估在肝脏多排螺旋计算机断层扫描中，使用去脂体重（LBW）作为造影剂用量和注射速率的主要决定因素的情况。
本符合健康保险流通与责任法案（HIPAA）的研究获得了机构审查委员会的批准。所有患者均签署了书面知情同意书。比较了四种方案。标准方案是注射125 mL碘帕醇，注射速率为4 mL/秒。总体重（TBW）方案是每千克TBW注射0.7 g碘。计算去脂体重（calculated LBW）方案和测量去脂体重（measured LBW）方案分别是根据计算或测量的男性和女性去脂体重，每千克分别注射0.86 g碘和0.92 g碘。三种实验方案的注射速率根据计算出的造影剂用量按比例确定。在门静脉期对每组患者的肝脏、门静脉和主动脉进行造影后衰减测量，并对每位患者的测量值进行求和。使用Levene检验测量同组患者之间增强的变异性。使用双尾t检验比较三种实验方案与标准方案。
对101例患者（每组25或26例患者）进行了数据分析，其中包括56名男性和45名女性（平均年龄53岁）。标准方案、TBW方案、计算去脂体重方案和测量去脂体重方案的平均衰减值总和分别为419 HU±50（标准差）、443 HU±51、433 HU±50和426 HU±33（P值均无统计学意义）。标准方案、TBW方案、计算去脂体重方案和测量去脂体重方案的衰减值总和数据的Levene检验结果分别为40±29、38±33（P = 0.83）、35±35（P = 0.56）和26±19（P = 0.05）。
通过在造影剂剂量计算中排除高度可变但灌注不良的脂肪组织，测量去脂体重方案可能会减少患者之间增强的变异性，同时保持肝脏和血管的增强效果令人满意。
