Covered airway stent placement for malignant tracheobronchial strictures in patients with an endotracheal tube

Treatment of aerodigestive fistulas with a novel covered metallic Y-shaped segmented airway stent customized with the assistance of 3D printing

Background

The management of aerodigestive fistula remains challenging. An airway stent that matches well with the individual geometry of the airway is needed for the treatment of the aerodigestive fistula. This study aimed to evaluate the feasibility of a novel covered metallic segmented Y-shaped airway stent customized with the assistance of 3D printing in aerodigestive fistulas involving the carina and distal bronchi and to compare the flexibility of the novel stent with the conventional wholly knitted stent.

Methods

In the flexibility study, we measured the longitudinal bending force and spring-back force of the segmented stent and wholly knitted stent. Patient-specific stents that were individually customized with the assistance of 3D printing technology were implanted in 26 patients with aerodigestive fistulas. The technical success, clinical success, Karnofsky performance status (KPS), and stent-related complications were recorded.

Results

The bending force and spring-back force of the segmented stent were significantly lower than those of the wholly knitted stent. Stent deployment was technically successful in all patients. Clinical success was obtained in 21 patients. The KPS of patients after the stenting procedure improved significantly compared with that before stenting (P<0.001). During follow-up, granulation tissue proliferation, sputum retention, stent migration, and intolerance of the stent were found in 2, 5, 1, and 1 patient, respectively.

Conclusions

The segmented metallic Y-shaped airway stent had greater flexibility than the wholly knitted stent in an ex vivo setting. Implantation of the segmented stent individually customized with the aid of 3D printing is feasible in treating aerodigestive fistulas involving the carina and bronchi distal to the carina.

Customization of stent design for treating malignant airway stenosis with the aid of three-dimensional printing

Background

The treatment of malignant stenosis involving the carina or bronchi is challenging due to complicated anatomy with individual variation, which makes it necessary to customize stents for each patient. Therefore, this study aims to evaluate the feasibility of a novel metallic segmented airway stent customized with the aid of three-dimensional (3D) printing for such cases.

Methods

The stents were individually customized with the aid of a 3D printed mold based on computed tomography (CT) images according to the anatomical features of the airway. A segmented design was applied on the junction part of the main stem and the branches to fit the dynamic changes of the carina angle. In 12 patients with airway stenosis caused by malignancies including esophageal cancer (EC) and lung cancer (LC), the stents were implanted. The technical and clinical success of the stenting procedure, Hugh-Jones (HJ) classification, Karnofsky performance status (KPS), and stent-related complications of patients were evaluated.

Results

The stenting procedure was technically successful in all patients, and 11 patients showed significant palliation of dyspnea after stenting. The HJ and KPS classification of patients after stent insertion improved significantly compared with those before stenting (P=0.003 and P=0.006, respectively). During follow-up, granulation tissue proliferation and sputum retention were found in two and four patients, respectively.

Conclusions

This study shows that the implantation of a novel stent designed with the aid of 3D printing is feasible for relieving dyspnea and improving performance status of patients with inoperable malignant stenosis involving the carina or bronchi.

A Pilot Study of a Novel through-the-Scope Self-Expandable Metallic Airway Stents Delivery System in Malignant Central Airway Obstruction

Objective

Self-expandable metallic (SEM) airway stents are an important approach to malignant central airway obstruction (CAO). SEM airway stent insertions are usually performed under fluoroscopic guidance over a guide wire placed through a flexible bronchoscope often resulting in a longer procedure time and exposure to radiation. In this pilot study, we designed a novel delivery system of the through-the-scope (TTS) SEM airway stent insertion and observed its feasibility.

Methods

From Jan 2015 to Sept 2016, 25 consecutive patients with inoperable malignant CAO were enrolled requiring airway stent implantation. All patients were followed up to death or at least 6 months.

Results

36 TTS stents were inserted into 25 patients using a flexible bronchoscope under general anesthesia or local anesthesia. All stents were successfully deployed directly through the working channel (2.8 mm diameter) of the flexible bronchoscope in 91.7% (33/36) of the subjects. The mMRC score and stenosis grade improved significantly after stent implantation. The common stent-related complications were secretion retention (25%, 9/36), development of granulation tissue (13.9%, 5/36), tumor in-growth (13.9%, 5/36), and hemoptysis (8.3%, 3/36). The 6-month overall survival (OS) was 44% (11/25).

Conclusion

The novel TTS stent release system was an effective and safe approach in malignant central airway obstruction.