Kay Fernando Uliana, Macedo Ana Carolina Sandoval, Chate Rodrigo Caruso, Szarf Gilberto, Teles Gustavo Borges da Silva, Sasdelli Neto Roberto, Funari Marcelo Buarque de Gusmão
Imaging Department, Hospital Israelita Albert Einstein, Sao Paulo, Brazil.
J Thorac Imaging. 2014 Mar;29(2):107-12. doi: 10.1097/RTI.0000000000000050.
The aim of the study was to compare the effects of different respiratory maneuvers in computed tomography pulmonary angiography for the diagnosis of pulmonary embolism (PE) on the contrast enhancement of pulmonary circulation and on the quality of lung window images.
A retrospective analysis of 520 examinations, half obtained after deep inspiration followed by breath-holding and half solely during breath-holding. Subjective quality analyses and objective measurements of pulmonary arterial enhancement and lung parenchyma attenuation were performed.
Elimination of deep inspiration reduced suboptimal opacification of the pulmonary artery (PA), from 7.3% to 2.7%, with 2.7% of the deep inspiration scans having attenuation values <150 Hounsfield units (HU). The prevalence of PE was similar between the groups (19% vs. 23%, respectively), with excellent interobserver diagnostic agreement (κ=0.89 to 0.91). Lung windows were compromised in 6.9% of the studies with respiratory pause, and these examinations had a higher attenuation of the lung parenchyma (median: -709.8 HU) compared with deep inspiration (-794.8 HU). A positive correlation between attenuation of the PA and the ascending aorta was observed (r=0.40 to 0.56).
Eliminating deep inspiration before image acquisition had opposite effects with the same magnitude: it caused a reduction in inadequate PA enhancement at the cost of an increased number of nondiagnostic lung images and did not compromise diagnostic consistency for PE.
本研究旨在比较计算机断层扫描肺动脉造影中不同呼吸动作对肺循环对比增强及肺窗图像质量的影响，以用于诊断肺栓塞（PE）。
回顾性分析520例检查，其中一半在深吸气后屏气时进行，另一半仅在屏气时进行。对肺动脉强化和肺实质衰减进行主观质量分析和客观测量。
消除深吸气可使肺动脉（PA）不理想的显影率从7.3%降至2.7%，深吸气扫描中有2.7%的衰减值<150亨氏单位（HU）。两组间PE的患病率相似（分别为19%和23%），观察者间诊断一致性良好（κ=0.89至0.91）。在6.9%的呼吸暂停研究中肺窗受到影响，与深吸气（-794.8 HU）相比，这些检查的肺实质衰减更高（中位数：-709.8 HU）。观察到PA与升主动脉的衰减之间存在正相关（r=0.40至0.56）。
在图像采集前消除深吸气有相反但程度相同的影响：它以增加非诊断性肺部图像数量为代价，减少了PA强化不足的情况，且不影响PE的诊断一致性。
