Chandrasekharan Rajsekar, Kulkarni Chinmay Bhimaji, Pullara Sreekumar Karumathil, Moorthy Srikanth
Department of Radiology, Amrita Institute of Medical Sciences, Amrita Vishwa Vidyapeetham, Kochi, Kerala, India.
J Clin Imaging Sci. 2021 Jul 14;11:38. doi: 10.25259/JCIS_97_2021. eCollection 2021.
The objective was to evaluate whether contrast dose based on lean body weight (LBW) protocol has the potential to reduce contrast volume in patients with high basal metabolic index (BMI) compared to total body weight (TBW)-based protocols.
The Institutional Review Board approval was obtained for this prospective study. Initially, a pilot study with a sample size of 150 patients was conducted to estimate the average fat fraction in our population. Then, CT angiography (CTA) for the thoracic and abdominal aorta was performed using a 256-multidetector computed tomography scanner in 117 patients who were undergoing screening for aortic aneurysm and vascular assessment of prospective transplant donors. The patients were divided into two groups: A TBW group ( = 60) and LBW group ( = 57). Lean body weight (LBW) was estimated from the patient weight, height, and gender using Hume's equation. The TBW group received 1.2 ml/kg contrast dose and the LBW group received 1.6 ml/kg contrast dose to achieve approximately equal iodine dose in both groups. Differences in the degree of aortic enhancement between the estimated LBW and TBW group were evaluated. In higher BMI patients (>25), the mean aortic enhancement (MAEnh) and the contrast volume delivered between the LBW and TBW group were compared.
Mean aortic enhancement (MAEnh) 422.45 (±74.5) Hounsfield unit (HU) in the TBW group and 432.67 (±69.4) HU in the LBW group showed no statistical difference ( = 0.439). In population with BMI >25, the contrast delivered in LBW protocol patients was significantly less ( = 0.00) compared to TBW protocol patients, with no significant difference in the MAEnh between the groups ( = 0.479).
CTA using a LBW protocol helps to significantly reduce the volume of contrast delivered, especially in patients with BMI >25 compared to TBW protocol, without compromising the aortic enhancement.
评估与基于总体重（TBW）的方案相比，基于瘦体重（LBW）的造影剂剂量方案是否有可能减少基础代谢指数（BMI）较高患者的造影剂用量。
本前瞻性研究获得了机构审查委员会的批准。最初，进行了一项样本量为150例患者的试点研究，以估计我们研究人群的平均脂肪含量。然后，使用256层螺旋CT扫描仪对117例接受主动脉瘤筛查和潜在移植供体血管评估的患者进行胸主动脉和腹主动脉CT血管造影（CTA）。患者分为两组：TBW组（n = 60）和LBW组（n = 57）。使用休谟公式根据患者的体重、身高和性别估算瘦体重（LBW）。TBW组接受1.2 ml/kg的造影剂剂量，LBW组接受1.6 ml/kg的造影剂剂量，以使两组的碘剂量大致相等。评估估算的LBW组和TBW组之间主动脉强化程度的差异。在BMI较高（>25）的患者中，比较了LBW组和TBW组之间的平均主动脉强化（MAEnh）和造影剂用量。
TBW组的平均主动脉强化（MAEnh）为422.45（±74.5）亨氏单位（HU），LBW组为432.67（±69.4）HU，无统计学差异（P = 0.439）。在BMI>25的人群中，与TBW方案的患者相比，LBW方案患者使用的造影剂明显更少（P = 0.00），两组之间的MAEnh无显著差异（P = 0.479）。
与TBW方案相比，使用LBW方案进行CTA有助于显著减少造影剂用量，尤其是在BMI>25的患者中，且不影响主动脉强化。
