不同层厚的CTPA图像对正常肺动脉分支的显示

Detection of normal pulmonary arteries using different slice thickness CTPA imagings

目的比较不同层厚CTPA图像对正常肺动脉分支的显示。方法35例肺野正常CTPA结果阴性的患者图像分别重建为0.625、1.25、2.5mm和5.0mm层厚四组,比较四组层厚图像对肺动脉分支的显示,同时评价四组层厚图像对肺动脉分支连续性的显示。结果0.625mm和1.25mm层厚组间肺动脉连续性优于2.5mm和5.0mm层厚组;对主肺动脉、左右肺动脉的显示,四组层厚图像间无差异;对肺段动脉的显示,0.625、1.25、2.5mm层厚组优于5.0mm层厚组(P=0.001);对亚段肺动脉和第5级肺动脉的显示,0.625mm和1.25mm层厚组间优于2.5mm和5.0mm层厚组(P=0.000);对第6级、第7级、第8级、第9级肺动脉的显示,四组间差异均有统计学意义。结论1.25mm层厚图像在显示肺小动脉分支方面与0.625mm能力相等,明显优于2.5mm和5.0mm层厚图像;而对于亚段肺动脉,应至少采用2.5mm层厚的图像观察,才能保证97%以上的亚段肺动脉被显示。

Objective To compare different thickness CT pulmonary angiography imaging for detecting the normal pulmonary arteries according to anatomic levels.Methods 35 patients＇ imaging data sets,which were normal in parenchyma and negative of CTPA,were reconstructed into different parameters of 0.625mm,1.25mm,2.5mm and 5.0mm slice thicknesses.The four different slice thickness imaging were compared for detecting the pulmonary arteries each other according to anatomic levels.And the succession of vessels of four different slice thickness imaging were compared each other at the same time.Results For succession of pulmonary arteries,there was no statistically significant difference between 0.625mm and 1.25mm slice thickness sets,and was superior to that of 2.5mm imaging and 5.0mm imaging（P0.05）.For detecting the main pulmonary artery,right and left pulmonary artery,there was no statistically significant difference between four slice thickness sets.For detecting the segment pulmonary arteries,there was no statistically significant difference between 0.625mm,1.25mm,and 2.5mm slice thickness sets,and was superior to that of 5.0mm imaging（P=0.001）.For detecting the subsegment and the fifth pulmonary arteries,there was no statistically significant difference between 0.625mm and 1.25mm slice thickness sets,and was superior to that of 2.5mm imaging and 5.0mm imaging（P=0.000）.For detecting the sixth,the seventh,the eighth,and the ninth pulmonary arteries,statistically significant difference was observed between four slice thickness imaging,and was 0.625mm1.25mm2.5mm5.0mm.Conclusion There is no statistically significant difference for detecting small pulmonary arteries between 0.625mm and 1.25mm slice thickness imagings,and is superior to that of 2.5mm and 5.0mm imaging.For subsegment pulmonary arteries,at least 2.5mm imaging or thinner imaging should be taken to ensure more 97% subsegment pulmonary arteries is detected.