离体猪肺的气管、支气管树遮盖表面显示法三维重建

Three Dimensional Reconstruction with Shaded Surface Display on Tracheobronchial Tree of Pig Lung in Vitro

目的 :探讨CT扫描层厚和间隔对三维重建的影响。材料和方法 :研究对象为10具离体新鲜猪肺标本。每一对象均接受层厚/间隔分别为3mm/3mm、3mm/1.5mm和1.5mm/1.5mm三种组合的EBCT扫描。扫描条件 :130kV/630mA ,扫描方式 :连续容积扫描(CVS)。其横断面图像转入Insight工作站(accuimagediagnosticcorporation,USA)进行三维重建 ,重建方式为遮盖表面显示法(SSD)。重建阈值为 -500Hu～ -300Hu。结果 :(1)新鲜离体猪肺标本气管和支气管的一、二级分支的三维测量与解剖测量相符合。(2)3mm/3mm、1.5mm/1.5mm和3mm/1.5mm三组扫描参数的猪肺气管、支气管一级分支的三维重建评分结果间无显著差异 ;对于二级支气管分支(3.67mm左右管径)的三维重建 ,3mm/1.5mm组的评分高于1.5mm/1.5mm组 ,有统计学意义 ;1.5mm/1.5mm组高于3mm/3mm组 ,也有统计学意义。结论 :降低层厚或重叠扫描进行的三维重建可更好地显示较细的支气管 。

Purpose:To explore the influence of slice thickness and interval of CT on three dimensional reconstruction.Materials and Method:The subjects were 10 pig lung in vitro.Every one was scanned by Electron Beam CT with 3mm/3mm?3mm/1.5mm and 1.5mm/1.5mm slice thickness/slice interval.The cross-section images were transmitted to the INSIGHT workstation and reconstructed with SSD(Shaded Surface Display),and their threshold setting were -500Hu to -300Hu.Results:1.The three dimensional measurement of diameter in trachea and the first to second bronchus branch was coordinated to that of amatomy measurement.2.To three group scanning parameters(3mm slice thickness and interval,1.5mm slice thickness/interval and 3mm slice thickness/1.5mm slice interval),the scores of their 3D images were of no difference in pig trachea and the first bronchus branch,but there were statistic significance among the three group in scoring of the second bronchus branch.Conclusion:The experimental part demonstrated that descending slice thickness or with overlapping scan can improve the imaging effect of 3D reconstruction of small bronchus.