Treatment Of Tracheobronchial Stenosis Research Articles

A flexible porous chiral auxetic tracheal stent with ciliated epithelium

Tracheal stent placement is a principal treatment for tracheobronchial stenosis, but complications such as mucus plugging, secondary stenosis, migration, and strong foreign body sensation remain unavoidable challenges. In this study, we designed a flexible porous chiral tracheal stent intended to reduce or overcome these complications. The stent was innovatively designed with a flexible tetrachiral and anti-tetrachiral hybrid structure as the frame and hollows filled with porous silicone sponge. Detailed finite element analysis (FEA) showed that the designed frame can maintain a Poisson's ratio that is negative or close to zero at up to 50% tensile strain. This contributes to improved airway ventilation and better resistance to migration during physiological activities such as respiration and neck movement. The preparation process combined indirect 3D printing with gas foaming and particulate leaching methods to efficiently fabricate the stent. The stent was then subjected to uniaxial tension and local radial compression tests, which indicated that it not only has the same desirable auxetic performance but also has flexibility similar to the native trachea. The porous sponge facilitated the adhesion of cells, allowed nutrient diffusion, and would prevent the ingrowth of granulation tissue. Furthermore, a ciliated tracheal epithelium similar to that of the native trachea was differentiated from normal human bronchial primary epithelial cells on the internal wall of the stent under air-liquid interface conditions. These results suggest that the designed stent has the potential for application in the treatment of tracheobronchial stenosis.

Is There a Beneficial Role for a Flexible Bronchoscopic Approach to Oesophageal Tumour-related Tracheobronchial Stenosis?

Interventional pulmonology, in particular, tracheobronchial stent insertion, has been well described in the treatment of tracheobronchial malignant disease. Its benefits are particularly obvious in patients with inoperable malignancy or in those unfit for surgery and have been extensively described. Fewer data exist on the benefits of using self-expanding metal stents (SEMS) inserted via flexible bronchoscopy in the treatment of tracheobronchial stenosis due to extrinsic compression or infiltration from primary oesophageal malignancy. We retrospectively reviewed all patients who had stent insertion via flexible bronchoscopy from 2002 to 2010 at our institution. We found 14 patients who had Ultraflex™ self-expanding metal stent insertion for this condition. We analysed this group of patients with respect to their presentation; indications for stent insertion over surgery; size, location, and number of stents inserted; sedative dose; complications of therapy; and survival time. We conclude that insertion of SEMS via flexible bronchoscopy is a safe and effective therapy for those individuals who require palliation or are too unfit for the general anaesthesia required for surgery. Moreover, this form of stent insertion may be performed by respiratory physicians in the bronchoscopy suite, rather than by their cardiothoracic counterparts in theatre.

Bronchoscopic balloon dilatation of tracheobronchial stenosis: long-term follow-up

Bronchoscopic balloon dilatation (BBD) has become a valuable tool in the treatment of tracheobronchial stenosis (TBS). The objective of this study was to assess the short- and long-term effects of BBD. A retrospective study that included all patients with confirmed, symptomatic stenosis, who underwent BBD between 2002 and 2008. A total of 92 BBD procedures were performed in 35 patients at our institute. Lung function studies were recorded for all patients before, immediately after and 1 month following the BBD. Long-term follow-up was for a mean of 33+/-4 months. All patients had initial success, including increased airway dimensions and symptom relief. No complications were noted related to BBD. Forced expiratory volume after one second (FEV(1)) was significantly increased after BBD (10.5%, p=0.03). These effects persisted for at least 1 month. Long-term follow-up, however, demonstrated the need for stent placement in 25 of 35 patients (71%), 210+/-91 days after BBD. Ten of 35 patients died 456+/-119 days after BBD due to progression of primary disease; all deaths were unrelated to the BBD procedures. BBD is a safe method that offers immediate symptomatic relief in both tracheal and bronchial stenosis. However, BBD is a temporary measure, as many patients will require definitive or additional treatment with laser or stent placement.

Modified neodymium-YAG laser in rigid bronchoscopy

The use of laser bronchoscopy in the treatment of tracheobronchial stenosis has been reported in the past. It is generally safe and effective; however, the complications of haemorrhage, airway perforation, or airway fire are relatively frequent among less experienced surgeons. We illustrate a modified technique of laser probe location to simplify the laser ablation procedure.

Nitinol stent for the treatment of tracheobronchial stenosis

The purpose of this study was to evaluate the potential utility of implantation of a nickel-titanium alloy (nitinol) stent for the treatment of malignant or benign tracheobronchial stenosis. We evaluated 18 patients (14 men and 4 women) who received 24 nitinol stents, between November 1997 and May 2000. All 18 patients had severe dyspnea caused by tracheobronchial stenosis. The underlying condition was malignant disease in 15 patients, and benign tracheal collapse in the other 3 patients. Implantation of the stent was successfully performed in all patients. Seventeen patients experienced immediate clinical improvement in respiratory symptoms. The remaining 1 patient with a bronchial fistule after lobectomy did not benefit, and died of pneumonia at 16 days after the implantation. In 15 patients, the procedure was performed using a flexible bronchoscope under local anesthesia alone, while the remaining 3 patients needed intravenous sedation. There was no complication resulting from the stent implantation. Among the 3 patients with benign tracheal collapse, 2 patients were alive at 746 and at 401 days after the stent implantation, at the time of this report. One patient with cicatricial stenosis after intubation died of heart failure due to previous myocardial infarction. Among the 15 patients with malignant disease, 4 patients have survived for 177 to 305 days to date, while the other 11 patients have died of primary malignancy with a mean survival duration of 60.2 days. The nitinol stent was effective in treating malignant or benign tracheobronchial stenosis, and had some remarkable advantages compared with other tracheobronchial stents. In stenting, most procedures can be performed using flexible bronchoscope under local anesthesia.

Treatment of Tracheo-bronchial Stenosis Following Tracheo-bronchial Tuberculosis

Treatment of Tracheo-bronchial Stenosis Following Tracheo-bronchial Tuberculosis

Granulation Stenosis Caused by a Dumon Stent Placed for Endobronchial Tuberculous Stenosis

Two patients with cicatric tracheobronchial stenosis caused by tuberculosis who suffered granulation stenosis after placement of a Dumon stent are reported. Dumon stents, which were long enough to cover the stenotic sites, were placed in the trachea and left main bronchus of each patient. Granulation tissue grew at both edges of the stent 3 or 4 months after stent placement, which caused restenosis and necessitated removal of the stents. The authors conclude that a Dumon stent for treatment of tracheobronchial stenosis caused by tuberculosis can cause granulation stenosis at the edges of the stent.

Comparison of tissue reactions in the tracheal mucosa surrounding a bioabsorbable and silicone airway stents

Background. Treatment of tracheobronchial stenosis is problematic. Conservative methods include stenting the stenotic area, but an ideal stent has not yet been developed. Bioabsorbable airway stents offer benefits; the extraction of the device is unnecessary, and the airway preserves its normal function after stent resorption. The aim of this study was to examine the suitability of self-reinforced poly- l-lactide as a material for an airway stent. Methods. A spiral airway stent made of 0.7-mm wire of self-reinforced poly- l-lactide was implanted operatively in 9 rabbits intratracheally; silicone stents served as controls. Results. Silicone stents had a tendency to become stenosed with encrustation material and to develop a hyperplastic polyp at both ends. Self-reinforced poly- l-lactide stents were well tolerated and caused no foreign body reaction, and they had a tendency to penetrate into the tracheal wall. They had disappeared at the end of the follow-up of 10 months. Conclusions. This experimental study showed that bioabsorbable self-reinforced poly- l-lactide is a promising material for an airway stent for treatment of airway stenosis.

Treatment of Tracheobronchial Stenosis with a Self-Expandable Metallic Stents

Treatment of Tracheobronchial Stenosis with a Self-Expandable Metallic Stents

Ｆｌｅｘｉｂｌｅ Ｅｎｄｏｓｃｏｐｉｃ Ｓｕｒｇｅｒｙ―適応と手技 Ｃ． 形状記憶合金を用いた気道ステント材による気管気管支狭窄治療法について

An innovative thermal shape-memory alloy stent was formulated for use in the treatment of tracheobronchial stenosis and airway collapse. The stent is designed to sustain the cartilagenous part of the airway with a cross-sectional profile of a horseshoe. The stent is made of a Ti-Ni alloy wire with a diameter of 0.5 mm with a transition temperature of 20°C and covered with silicone. The stents cooled in ice-water were placed through an endotracheal tube into the targeted site using a flexible bronchial fiberscope. Experimental study using tracheomalasial model dogs revealed that the stent was effective in overcoming airway stenosis. Encouraged by these promising results in experimental study, we have begun to study clinical applications of the thermal shape-memory alloy stent.

Gianturco self-expanding metallic stents in treatment of tracheobronchial stenosis after single lung and heart and lung transplantation

Three patients with recurrent bronchial stenosis following single lung transplant (SLTx), and one patient with tracheal stenosis following heart-lung transplantation (HLTx), not responding to repeated dilatations (3 patients) and prolonged use of silastic stents (patient with tracheal stenosis), have been treated by the endoscopic insertion of Gianturco self-expanding metallic stents under fluoroscopic control. The stent resulted in immediate improvement in respiratory function in all four patients. One patient (SLTx) had early bronchial re-stenosis due to growth of granulation tissue within the stent which was successfully treated by cryotherapy. In one patient (HLTx), a left lower lobe bronchial stenosis developed 14 months after tracheal stenting. The metallic stent appears to be a promising device in the management of recurrent or resistant bronchial stenosis following SLTx or tracheal stenosis after HLTx.