Assessment of major airway obstruction using image analysis of digital CT information

摘要

Major airway obstruction (trachea, right and left main bronchi) is an important cause of morbidity and mortality. Management requires adequate assessment of the position, extent and severity of the obstructing or stenotic segment. The objective of this study was to evaluate 3D reconstruction of the major airways using volumetric image display and analysis (VIDA), in subjects with major airflow obstruction. We have evaluated five subjects with major airway obstruction using Electron Beam Computed Tomography (EBCT) with a contiguous 3 mm slice thickness at total lung capacity. The digital information was transferred to a Sun Workstation (SPARC 5) for data analysis using VIDA. From this data set, the airway dimensions were calculated using a method for airway centerline determination and slice reformatting so as to section the airway perpendicular to its local long axis. Once appropriately sectioned, a number of different methods were used in edge finding. The airways were also presented as a surface rendered 3D image in either still or movie format. Finally, all subjects underwent flexible bronchoscopy to assess the abnormalities by direct visualization, with results of the bronchoscopic assessment being compared to the VIDA measurements. In all subjects, the volumetric image display and analysis gave anatomically correct and detailed images, which could be accurately measured. This information enabled appropriate pre-planning of operative corrective procedures, that included laser therapy, stent placement and balloon bronchoplasty. We conclude that the volumetric image display and analysis provides useful and reliable information for the management of major airflow obstruction.