Intraoperative cone beam computed tomography of tracheal stenting for stenosis and fistula diseases: a retrospective cohort study

Background: Angiographic computed tomography (CT) is useful in various medical contexts, but little research has been presented regarding the application of cone beam CT (CBCT) in airway stenting. This study set out to evaluate the clinical feasibility of using CBCT in airway stent placement in a single-center retrospective cohort. Methods: A total of 228 patients with stenosis or fistula diseases were treated with metallic airway stents in the First Affiliated Hospital of Zhengzhou University from January 1, 2015, to December 31, 2018. Of them, 128 patients underwent fluoroscopy-guided airway stenting. CBCT scanning was performed on the other 100 patients during and after treatment, and their images were compared with those from postoperative multidetector CT (MDCT). The outcomes and complications in the CBCT-guided and fluoroscopy-guided groups were also assessed via Pearson's chi(2) test or Fisher's exact test. Results: Tracheal stenting was performed successfully on the first attempt for 90 patients in the CBCTguided group and 123 patients in the fluoroscopy-guided group. The mean measured diameters of the central airway in the CBCT images and MDCT images were 18.2 +/- 2.81 and 19.0 +/- 2.33 mm, respectively, and the mean lengths were 58.7 +/- 16.82 and 58.5 +/- 17.06 mm, respectively. In the CBCT-guided group and the fluoroscopy-guided group, the mean scores for visibility of the distal bronchus were 3.7 +/- 0.49 and 3.9 +/- 0.34, respectively; the mean scores for the pulmonary parenchyma were 3.3 +/- 0.71 and 3.9 +/- 0.31, respectively; and the mean scores for the airway above the upper stent graft were 1.8 +/- 0.41 and 4.0 +/- 0.20, respectively. Two of the three anatomical areas were reproduced in a diagnostically relevant way. The major complications rate was 7% and 19% in the CBCT-guided and fluoroscopy-guided groups, respectively. Conclusions: CBCT produces images with sufficient quality to replace MDCT as a reasonable control measure after stent implantation, and its use during surgery reduces complications relating to airway stent placement.