Endobronchial Stent Placement Research Articles

An Endobronchial Cyst with Squamous Metaplasia at the Location of an Airway Stent

We report a case of an endobronchial cyst discovered on routine surveillance bronchoscopy 1 year after an endobronchial stent was placed in a 52-year-old woman who underwent a single left-lung transplant. The endobronchial stent was noted to be in proper position in the left mainstem bronchus with green, purulent secretions. At the distal edge of the stent was a pink fleshy mass obstructing 70% of the bronchus. An endobronchial biopsy was preformed and after the first “bite” of the mucosa, the entire mass disappeared and clear fluid was released. The endobronchial biopsy indicated squamous metaplasia. Cultures grew Streptococcus pneumoniae and transbronchial biopsy revealed mild rejection without airway involvement. The patient was treated with intravenous antibiotics and steroids. Repeat bronchoscopy 6 months later showed no recurrence of the mass. We conclude that the endobronchial cyst in this patient may have originated from a pre-existing “extracellular cyst” associated with the development of metaplasia. The metaplastic changes are likely associated with a foreign body reaction from endobronchial stent placement exacerbated by chronic inflammation. A review of the literature on endobronchial lesions is presented.

Balloon Dilation and Endobronchial Stent Placement for Bronchial Strictures after Lung Transplantation

To evaluate the effect of balloon dilation and endobronchial stent placement for bronchial fibrous stenoses and bronchomalacia after lung transplantation. Bronchial dilation and/or stent placement was performed on 25 lung transplant recipients. Indications included severe dyspnea with postobstructive pneumonia (n = 24) and respiratory failure (n = 1). All patients underwent pulmonary function testing (PFT) before and after bronchial dilation, the results of which were evaluated for changes. A total of 63 procedures were performed between February 1996 and December 1998. Thirty-five lesions were treated (18 were due to bronchomalacia, 17 were due to fibrosis). Areas treated included the left mainstem bronchus (n = 11), bronchus intermedius (n = 10), right mainstem bronchus (n = 7), left upper lobe bronchus (n = 4), right lower lobe bronchus (n = 2), and right middle lobe bronchus (n = 1). Bronchoscopic and/or bronchographic follow-up ranged from 1 to 34 months (mean, 15 months). Six-month primary patency of stents placed for bronchomalacia was 71% (10 of 14), with three of the four occlusions caused by mechanical failure of Palmaz stents in the mainstem bronchi. Six-month primary patency for treatment of fibrous strictures was 29%. Secondary patency at 1 year was 100% for both bronchomalacia and fibrous strictures. After treatment, there was a significant improvement in mean PFT results (P = .01-.0001). There was one acute complication, obstruction of the left lower lobe bronchus by a Wallstent treated by dilating a hole in the side of the stent. Balloon dilation and stent placement are safe and effective for bronchial strictures and bronchomalacia after lung transplantation, resulting in significant improvement in PFT results. However, there is almost universal restenosis in patients treated for fibrous strictures necessitating reintervention for prolonged patency.

Airway Simulation to Guide Stent Placement for Tracheobronchial Obstruction in Lung Cancer

Background. To effectively palliate large airway obstruction in advanced unresectable lung cancer (stage IIIB or IV), we developed an airway imaging technique to guide selective endobronchial metallic stent placement. Methods. Fourteen consecutive patients with severe dyspnea (American Thoracic Society grade 4) had a combination of fiberoptic bronchoscopy, chest roentgenography, computed tomographic scanning, helical computed tomography with three-dimensional reconstruction, and intraluminal bronchography with selective bronchial guidewire placement under fluoroscopy to visually reconstruct and simulate the abnormal airway before and during stent placement. Wallstent or Gianturco intraluminal stents were used alone or in combination (up to five stents) to establish patency of the distal trachea and the major bronchi. Results. All 14 patients had successful deployment with initial relief of airway stenosis (>75% predicted diameter). No procedural complications were noted. However, technical problems included stent foreshortening and imprecision of placement, misinterpretation of bronchography (mucous versus tumor), and airway maintenance during manipulation. Length of stay attributable to the procedure averaged 4 days. Stent placement initially improved the dyspnea score in 7 of 14 patients. Five of 14 died in less than 1 month, with the remainder alive at up to 8 months’ follow-up. Of those surviving more than 1 month, the Karnofsky score improved in 4 and was unchanged in 5, with 2 dependent (Karnofsky score <50), 3 functional (Karnofsky score, 50 to 70), and 4 active (Karnofsky score >70). Conclusions. A protocol combining helical computed tomography with three-dimensional reconstruction, bronchography, and bronchoscopy allows accurate assessment of malignant airway obstruction to facilitate intralumenal stent placement for relief of stenosis. Patient selection to favor effective palliation and cost effectiveness has yet to be defined.