Raczeck Paul, Minko Peter, Graeber Stefan, Fries Peter, Seidel Roland, Buecker Arno, Stroeder Jonas
1 Department of Diagnostic and Interventional Radiology, Saarland University Medical Center, Kirrberger Str 1, 66421 Homburg/Saar, Germany.
2 Institute of Medical Biometry, Epidemiology and Medical Informatics, Saarland University Medical Center, Homburg/Saar, Germany.
AJR Am J Roentgenol. 2016 Mar;206(3):481-6. doi: 10.2214/AJR.15.15176.
The purpose of this study was to prospectively compare the effect of inspiration and resting expiratory position on contrast enhancement in pulmonary CT angiography (CTA) in a randomized clinical trial.
In accordance with a power analysis performed before the study, we included 28 consecutive patients referred for evaluation of suspected pulmonary embolism in this prospective study. Patients were randomly assigned to perform either inspiration (n = 14; six men, eight women; mean age [SD], 38.1 ± 9.8 years) or resting expiratory position (n = 14; six men, eight women; mean age: 42.1 ± 9.2 years). All patients were scanned in a standardized supine position and scanning parameters were kept constant. Contrast medium was injected automatically with bolus tracking. Objective pulmonary vessel attenuation was quantified with digital measurement. Results were analyzed by using the unpaired t test and chi-square test.
Patients in the resting expiratory position showed significantly higher contrast attenuation than those who performed inspiration (302.9 ± 11.9 HU vs 221.5 ± 20.9 HU; p < 0.01). There were no significant differences in applied total volume of contrast agent (76.8 ± 1.9 mL vs 75.7 ± 1.6 mL; p = 0.6765), total volume including normal saline bolus (116.8 mL ± 2.8 mL vs 121.8 mL ± 2.3 mL; p = 0.1724) or flow rate (3.1 mL/s ± 0.1 mL/s vs 3.2 mL/s ± 0.1 mL/s).
Pulmonary CTA should be performed in the resting expiratory position, and patients should be instructed to avoid inspiration to achieve the highest possible attenuation in the pulmonary arteries.
本研究的目的是在一项随机临床试验中前瞻性比较吸气位和静息呼气位对肺部CT血管造影（CTA）中对比剂增强效果的影响。
根据研究前进行的功效分析，我们纳入了28例连续转诊来评估疑似肺栓塞的患者进行这项前瞻性研究。患者被随机分配为吸气位组（n = 14；6名男性，8名女性；平均年龄[标准差]，38.1±9.8岁）或静息呼气位组（n = 14；6名男性，8名女性；平均年龄：42.1±9.2岁）。所有患者均在标准化仰卧位进行扫描，扫描参数保持恒定。采用团注追踪自动注射对比剂。通过数字测量对目标肺血管衰减进行量化。结果采用成组t检验和卡方检验进行分析。
静息呼气位组患者的对比剂衰减明显高于吸气位组患者（302.9±11.9 HU对221.5±20.9 HU；p<0.01）。对比剂应用总量（76.8±1.9 mL对75.7±1.6 mL；p = 0.6765）、包括生理盐水团注在内的总量（116.8 mL±2.8 mL对121.8 mL±2.3 mL；p = 0.1724）或流速（3.1 mL/s±0.1 mL/s对3.2 mL/s±0.1 mL/s）均无显著差异。
肺部CTA应在静息呼气位进行，并且应指导患者避免吸气，以在肺动脉中获得尽可能高的衰减。
