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Severe left mainstem bronchial stenosis due to tuberculosis treated with modified hourglass stent A, B: CT and bronchoscopic images showing severe LMSB stenosis (arrow). C, D: Significant granulation tissue complicating straight silicone stent. E, F: Modified hourglass stent fitting well in the LMSB CT: computed tomography; LMSB: left mainstem bronchus
Source publication
Central airway obstruction often presents with airway narrowing of differing internal diameters. Conventional straight stents do not fit these airways well and are prone to migration. We present a series of cases where hourglass-shaped silicone stents were customized intra-operatively to fit airway obstructions of both malignant and non-malignant e...
Contexts in source publication
Context 1
... employment purposes, she underwent a chest X-ray, which noted a possible airway abnormality. The follow-up CT confirmed LMSB stenosis ( Figure 3A). Surgical consultation recommended left pneumonectomy but she declined. ...
Context 2
... revealed a significant fibrotic stricture of the LMSB ( Figure 3B). This was recanalized using an electrocautery knife and balloon dilation. ...
Context 3
... did not fit well, but attempts were made to modify its shape and it was left in place. With this intervention, her symptoms improved temporarily, but she required two more bronchoscopies over the ensuing four months for recurring symptoms; stent-related granulation tissue had resulted in an uneven airway with mild obstruction proximal to the stent but significant distal obstruction ( Figures 3C, 3D). Ultimately, during repeat bronchoscopy, the stent was removed as per the patient's request and because of a suspected stent infection. ...
Citations
... Tracheobronchial silicone stents were first described by Dumon in 1990 [43]. Unlike metallic stents, silicone stents must be deployed using a rigid bronchoscope, but can be customized at the time of procedure [44,45]. For instance, the stent can be cut to a certain length and side holes can be cut out to allow for ventilation of the bypassed normal airway branches. ...
Airway stents, first developed in the 1980s, have become fundamental in managing a multitude of airway pathologies and complications within the field of interventional pulmonology. The primary function of an airway stent is to re-establish airway patency and integrity when obstruction, stenosis, anastomotic dehiscence, or fistulae develop as a result of various malignant or benign conditions. Nevertheless, airway stents are foreign bodies that can result in complications. In this review article, we will discuss airway stents and their ongoing role in the management of several malignant and benign diseases. We will describe indications for airway stenting and review the elements that must be taken into consideration for optimal patient and stent selection. Given the prevalence of data regarding therapeutic bronchoscopy and airway stenting in malignant airway obstruction, much of the discussion in this review will focus on stent placement for that indication. We will also review the data as it pertains to safety, efficacy, and complications after stent placement, and conclude with a discussion of the future applications and research avenues related to airway stents.
... The Dumon 'hourglass' model (BostonMedical Products, Westborough, MA) was designed for cases with intrinsic or extrinsic luminal compression that abruptly change diameter, such as in subglottic stenosis, consequently preventing single-diameter stents from fitting properly. 16 Silicone Y stents have been used for many decades. ...
The first dedicated tracheobronchial silicone stent was designed by the French pulmo-nologist Jean-Paul Dumon. The most common indications for stenting are to minimise extrinsic airway compression from mass effect, maintain airway patency due to intrinsic obstruction or treat significant nonmalignant airway narrowing or fistulae. Silicone stents require rigid bronchoscopy for insertion; however, they are more readily repositioned and removed compared with metallic stents. Metallic stents demonstrate luminal narrowing when loads are applied to their ends, therefore stents should either be reinforced at the ends or exceed the area of stenosis by a minimum of 5 mm. Nitinol, a nickel-titanium metal alloy, is currently the preferred material used for airway stents. Airway stenting provides effective palliation for patients with severe symptomatic obstruction. Drug-eluting and three-dimensional printing of airway stents present promising solutions to the challenges of the physical and anatomical constraints of the tracheobronchial tree. Biodegradable stents could also be a solution for the treatment of nonmalignant airway obstruction.
... Airway stenosis directly below the acoustic cavity requires modification of the hourglass-shaped silicone stent to completely fit the waist of the stent to the stenosis; otherwise, it may cause coughing, granulation, airway restenosis, and stent displacement. Modifications to the stent can better accommodate anatomical and pathological alterations of the airway (5). Two factors are mainly considered for the modification: to make the stent waist fit with the stenosis, and to keep the upper edge of the stenosis at a suitable distance from the acoustic canal. ...
Background
Benign subglottic stenosis has been a challenging illness to treat and manage in clinical because of its special anatomical location, and easy recurrence of the condition, which can cause life-threatening asphyxia. For patients who are not suitable for surgery or in urgent need of preoperative transitional treatment, respiratory endoscopy-guided stent placement becomes an alternative treatment option.
Case Description
Clinical data were collected from four patients who received treatment at the Jining First People’s Hospital due to benign subglottic stenosis, which was achieved after tracheal intubation/tracheotomy. All patients were male, admitted with shortness of breath, with an average of 45±8.95 years. Among them, three patients refused the surgery, and one patient was unable to tolerate the surgery. Despite repeated intervention under bronchoscopy, airway stability was still not maintained. By inserting modified hourglass silicone stents, the patient’s symptoms were improved and the clinical efficacy was satisfactory. Regular follow-up showed good stent position and no granulomatous growth at the ends of the stents.
Conclusions
This is an initial report of improved hourglass stents used for the treatment of benign subglottic airway stenosis. In these cases, the modified hourglass stents had good efficacy and fewer complications and were also accepted by patients.
... They are typically lined with studs that help anchor the stents to the airways but also allow a small space between the airway and the stent, allowing for the continued benefit of mucociliary function. Given their intrinsically-variable shape, the Y and hourglass stents, in particular, can be creatively modified to tailor to the needs of a given obstructed airway (19,20). ...
Central airway obstruction is a serious complication of various diseases, most often malignancy. Malignant etiologies include primary lung cancer as most common though metastases from various other cancers can obstruct the airways as well. Benign etiologies include inflammatory or fibrotic changes due to prior airway interventions (e.g., endotracheal intubation or tracheostomy) or specific autoimmune conditions. Different interventional modalities exist including various electrosurgical or mechanical debulking tools, though these are sometimes insufficient or contraindicated for the purpose of restoration of airway patency. The placement of stents is thus needed in certain particularly complex or refractory cases. Airway stenting requires careful patient selection and stent selection along with a thorough knowledge of relevant anatomy and procedural technique. Indeed, certain clinical presentations are better suited for stent placement and more likely to achieve a symptomatic benefit. Moreover, a variety of stents exist with each having different attributes that may better fit specific conditions. Complications must be managed properly as well. These include stent migration, granulation tissue formation, and stent-related infection which can have clinically significant consequences. In this review, we will discuss airway stenting for central airway obstruction with regard to these various subject areas as well as conclude with discussion of future research directions.
