胸腔入口平面气管右旁气囊影:临床与影像初步观察

Clinical and Imaging Preliminary Observation of Right Paratracheal Air Cysts in the Thoracic Inlet

目的探讨胸腔入口平面气管右旁气囊影(right paratracheal air cysts,RPAC)临床与影像特点及意义。资料与方法在PACS浏览近半年就诊患者临床及胸部MSCT信息,搜集其中MSCT发现的RPAC影像资料进行分析;并随机选取胸部MSCT无RPAC患者60例作为对照组,比较两者气管指数。结果 6213例患者发现RPAC 64例,发生率1.03%,63例在气管右后侧,1例在气管左后侧。水平直径:(1.26±0.64)cm,纵向直径:(2.02±1.21)cm;体积:(1.92±1.05)cm3,其中慢性支气管炎肺气肿组:(2.13±0.94)cm3,无慢性支气管炎无肺气肿组:(0.95±0.47)cm3(t=5.32,P<0.05);38例复查病例RPAC体积变化:(0.12±0.08)cm3(t=2.33,P>0.05)。RPAC发生率及所占比例随年龄增大而增加。气管指数平均值RPAC组:0.64±0.27,对照组:1.16±0.35(t=6.12,P<0.05)。RPAC与气管间细管状气道影常规厚层(7 mm)显示7例,亚毫米(0.75 mm)显示27例(t=8.62,P<0.01);35例CT仿真内镜(CTVE)显示气管内表面局限性凹陷或小孔,27例VR清晰显示RPAC与气管间连接的空间关系。结论 RPAC实质可能多为气管憩室,MSCT能显示其影像特征及其与气管关系,为诊断提供客观依据并提示阻塞性肺病或肺气肿可能。

Objective To explore the clinical and imaging features of right paratracheal air cysts（RPAC） in the thoracic inlet and its significance.Materials and Methods In the PACS,the thoracic clinical and MSCT information of patients treated in the past six months was browsed,in which the RPAC imaging data found by MSCT was collected and analyzed;and 60 cases without RPAC in chest were randomly selected as the control group,The trachea index between the study group and the control group was compared.Results The RPAC in the thoracic inlet were found in 64 of 6213 patients,the ratio was 1.03%,The position of RPAC was located at the right posterolateral aspect of trachea in 63 of 64 patients,only one was located at the left posterolateral aspect of trachea.The mean diameter of RPAC was 1.26±0.64 cm in the axial plane and 2.02±1.21 cm in the vertical plane,The mean volume of RPAC was 1.92±1.05 cm3in all 64 patients and 2.13±0.94cm3 in bronchitis emphysema groups and 0.95±0.47 cm3 in no bronchitis emphysema groups,There were significant differences（P0.05） between two groups;The volume change of RPAC in 38 cases by review was 0.12±0.08 cm3,This change was no statistically significant（P0.05）.With age-related increase,the incidence and proportion of RPAC were increased.The mean value of trachea index was 0.64±0.27 in the RPAC group and 1.16±0.35 in the control group,There were significant differences（P0.05） between two groups.The fine tubular airway shadows between RPAC and trachea was displayed 7 cases in conventional thick layer（7 mm） and 27cases in sub-millimeter thin layer（.75 mm）（P0.01）;The limited sag or holes in endotracheal surface was displayed in 35 cases by CTVE;The space connective relations between RPAC and trachea was clear display in 27 cases by VR.Conclusion The most probable nature of RPAC in the thoracic inlet is tracheal diverticulum,MSCT can show the image characteristics and its relationship with the trachea,and to provide theoretical evidence for diagnosis and suggest the possibilities of presence of obstructive lung disease or emphysema.