An Operator Independent Method for Bronchial Tree Analysis from Trachea to the Small Airways Using Volumetric Multi-Detector Computed Tomography

Abstract

Measurement of bronchial lumen and wall thickness of large and small airways from CT images is useful in clinical practice for the characterization of several diseases. Automatic methods are high desirable to save reporting time and to improve measurement reproducibility. In this study airways segmentation was performed by the application of a multi-step algorithm including airways segmentation, scheletonization and classification of the bronchial three, and calculation of the bronchial diameter and the airway wall thickness. The proposed method was validated on images from ten patients with suspect airways disease, comparing measurements obtained by the proposed algorithm with manual measurements performed by two expert users. Wall thickness and lumen diameter automatic measurements performed by the proposed approach were interchangeable with manual measurements, in the sense that the difference in measurements between the automatic method and the manual analysis is equivalent to the inter-observer variability. The proposed approach thanks to their simplicity showed computational efficiency, reliability, and was demonstrated to be totally operator-independent.

Impact of 3D printing on the surgical management of tracheal stenosis associated to pulmonary sling: a case report

“…3D printing technology was proposed to have a detailed definition of the patient's anatomy. To build the 3D model, images analysis procedure was performed on the entire CT dataset as 3D data volume using a custom operator independent algorithm, able to perform airways segmentation and measurement (5). To extract the airways path geometry we applied the following three procedures: airways mask computation, computation of a hierarchical binary tree defining the airways segments, and computing lumen edge for all bronchial segments.…”

“…CTS is rare lesions considered to increase mortality risk of PS. The complexity is due to the dimension of the children's trachea that can be very small especially in the neonates (1)(2)(3)(4)(5)(6)(7)(8). Management by a dedicated tracheal team and ST have been considered a breakthrough in the improvement of the outcomes (2).…”

“…However, as other authors have stated (6), "one slide cannot fit all", the different anatomical patterns of tracheal stenosis make standardization of the surgical techniques difficult. The use of 3D printing has been demonstrated to be beneficial instead a bidimensional conventional exams, even when reconstructed three-dimensionally on the computer screen (4,5). The advantage of 3D printing lies precisely in the possibility to see and touch the model miming what will appear on operative field, manipulate it or simulating the surgical technique.…”

“…This choice, we believe, gave to the patient the cumulative risk of two surgical techniques, with dehiscence as the most dangerous one and the dramatic postoperative course confirmed our hypothesis. In order to improve subsequent outcomes, the case was discussed by the multidisciplinary tracheal team, and the use 3D printing was suggested on the base of the encouraging result described in the literature with its use (4,5,7). The necessity of a more specific knowledge of the anatomical pattern of the cases considered to be complex and the better technique to approach those cases, rise in our practice from the growing number of reports about favourable result by conservative management of CTS associate to PS (8).…”