Laryngotracheal augmentation using titanium mesh

Length of Stay in Patients Undergoing Tracheoplasty: A NSQIP Study

BACKGROUND

Prolonged length of stay (LOS) has been associated with increased morbidity and resource utilization in various surgical procedures. We aim to determine factors associated with increased hospital stay in patient undergoing tracheoplasty.

METHODS

The 2012-2018 National Surgical Quality Improvement Program (NSQIP) database was queried for patients undergoing tracheoplasty. Patient LOS was the primary clinical outcome. A LOS >75th percentile was considered as prolonged and was utilized for bivariate analysis of demographic, comorbidity, and operative characteristics. LOS was utilized as a continuous variable for multivariate linear regression analysis.

RESULTS

A total of 252 patients were queried. The majority of patients were female (67.5%), white (82.4%), and over the age of 65 (77.0%). Patients had a median LOS of 7 days with the 75th percentile cutoff being defined at 10 days. On bivariate analysis of associated comorbidities, patients with prolonged LOS were more commonly obese (72.4% vs. 53.1%, p = 0.009), diabetic (37.9% vs. 16.5%, p < 0.001), dyspneic (58.6% vs. 40.7%, p = 0.016), and had chronic steroid use (25.9% vs. 12.9%, p = 0.018). Multivariable logistic regression analysis demonstrated significant associations between prolonged LOS and both chronic obstructive pulmonary disorder (COPD) (OR: 3.43, p = 0.020) and chronic steroid use (OR: 3.81, p = 0.018).

CONCLUSIONS

This study elucidates factors associated with prolonged LOS in patients undergoing tracheoplasty. Patients with COPD and chronic steroid use were significantly associated with prolonged LOS.

LEVEL OF EVIDENCE

4 Laryngoscope, 2022.

3D-bioprinted tracheal reconstruction: an overview

Congenital tracheomalacia and tracheal stenosis are commonly seen in premature infants. In adulthood, are typically related with chronic obstructive pulmonary disease, and can occur secondarily from tracheostomy, prolong intubation, trauma, infection and tumors. Both conditions are life-threatening when not managed properly. There are still some surgical limitations for certain pathologies, however tissue engineering is a promising approach to treat massive airway dysfunctions. 3D-bioprinting have contributed to current preclinical and clinical efforts in airway reconstruction. Several strategies have been used to overcome the difficulty of airway reconstruction such as scaffold materials, construct designs, cellular types, biologic components, hydrogels and animal models used in tracheal reconstruction. Nevertheless, additional long-term in vivo studies need to be performed to assess the efficacy and safety of tissue-engineered tracheal grafts in terms of mechanical properties, behavior and, the possibility of further stenosis development.

Tissue-Engineered Larynx: Future Applications in Laryngeal Cancer

Purpose of Review

This article reviews the latest developments in tissue engineering for the larynx with a specific focus on the treatment of laryngeal cancer.

Recent Findings

Challenges in tissue engineering a total larynx can be divided into scaffold design, methods of re-mucosalization, and how to restore laryngeal function. The literature described a range of methods to deliver a laryngeal scaffold including examples of synthetic, biomimetic, and biological scaffolds. Methods to regenerate laryngeal mucosa can be divided into examples that use a biological dressing and those that engineer a new mucosal layer de novo. Studies aiming to restore laryngeal function have been reported, but to date, the optimum method for achieving this as part of a total laryngeal transplant is yet to be determined.

Summary

There is great potential for tissue engineering to improve the treatments available for laryngeal cancer within the next 10 years. A number of challenges exist however and advances in restoring function must keep pace with developments in scaffold design.

[The long-term results of the application of the polypropylene mesh for the plastic correction of extensive laryngo-tracheostomas]

The objective of the present study was to estimate the long-term results of the closure of large laryngeal and tracheal stomas with the use of the polypropylene mesh. The study included 33 adult patients presenting with extensive laryngeal and tracheal stomas. A total of 34 surgical interventions were performed for alloplastic correction of these defects. The complete closure of the tracheal and laryngeal defects with the incorporation of the prosthesis and restoration of respiration was achieved in 88.2% of the alloplastic procedures. The long-term follow-up of the treated patients (median: 75 months) failed to reveal any signs of mesh rejection. Moreover, none of the patients reported an appreciable feeling of discomfort at the site of mesh localization. Thus, the results of the study indicate that the alloplastic correction of laryngeal and tracheal stomas with the implantation of the modern mesh prostheses from polypropylene monofilaments provides the safe and reliable alternative to autoplastic surgery. Low rigidity of the modern prosthetic meshes ensures good immediate results of implant survival in the absence of long-term complications associated with the durable presence of the polypropylene mesh on the neck.

Introducing a 3-dimensionally Printed, Tissue-Engineered Graft for Airway Reconstruction

Objective:

To use 3-dimensional (3D) printing and tissue engineering to create a graft for laryngotracheal reconstruction (LTR).

Study Design:

In vitro and in vivo pilot animal study.

Setting:

Large tertiary care academic medical center.

Subjects and Methods:

A 3D computer model of an anterior LTR graft was designed. That design was printed with polylactic acid on a commercially available 3D printer. The scaffolds were seeded with mature chondrocytes and collagen gel and cultured in vitro for up to 3 weeks. Scaffolds were evaluated in vitro for cell viability and proliferation. Anterior graft LTR was performed on 9 New Zealand white rabbits with the newly created scaffolds. Three animals were sacrificed at each time point (4, 8, and 12 weeks). The in vivo graft sites were assessed via bronchoscopy and histology.

Results:

The in vitro cell proliferation assay demonstrated initial viability of 87.5%. The cells proliferated during the study period, doubling over the first 7 days. Histology revealed that the cells retained their cartilaginous properties during the 21-day study period. In vivo testing showed that all animals survived for the duration of the study. Bronchoscopy revealed a well-mucosalized tracheal lumen with no evidence of scarring or granulation tissue. Histology indicated the presence of newly formed cartilage in the region where the graft was present.

Conclusions:

Our results indicate that it is possible to produce a custom-designed, 3D-printed, tissue-engineered graft for airway reconstruction.

Controlled implant/soft tissue interaction by nanoscale surface modifications of 3D porous titanium implants

Porous titanium implants are widely employed in the orthopaedics field to ensure good bone fixation. Recently, the use of porous titanium implants has also been investigated in artificial larynx development in a clinical setting. Such uses necessitate a better understanding of the interaction of soft tissues with porous titanium structures. Moreover, surface treatments of titanium have been generally evaluated in planar structures, while the porous titanium implants have complex 3 dimensional (3D) architectures. In this study, the determining factors for soft tissue integration of 3D porous titanium implants were investigated as a function of surface treatments via quantification of the interaction of serum proteins and cells with single titanium microbeads (300-500 μm in diameter). Samples were either acid etched or nanostructured by anodization. When the samples are used in 3D configuration (porous titanium discs of 2 mm thickness) in vivo (in subcutis of rats for 2 weeks), a better integration was observed for both anodized and acid etched samples compared to the non-treated implants. If the implants were also pre-treated with rat serum before implantation, the integration was further facilitated. In order to understand the underlying reasons for this effect, human fibroblast cell culture tests under several conditions (directly on beads, beads in suspension, beads encapsulated in gelatin hydrogels) were conducted to mimic the different interactions of cells with Ti implants in vivo. Physical characterization showed that surface treatments increased hydrophilicity, protein adsorption and roughness. Surface treatments also resulted in improved adsorption of serum albumin which in turn facilitated the adsorption of other proteins such as apolipoprotein as quantified by protein sequencing. The cellular response to the beads showed considerable difference with respect to the cell culture configuration. When the titanium microbeads were entrapped in cell-laden gelatin hydrogels, significantly more cells migrated towards the acid etched beads. In conclusion, the nanoscale surface treatment of 3D porous titanium structures can modulate in vivo integration by the accumulative effect of the surface treatment on several physical factors such as protein adsorption, surface hydrophilicity and surface roughness. The improved protein adsorption capacity of the treated implants can be further exploited by a pre-treatment with autologous serum to render the implant surface more bioactive. Titanium microbeads are a good model system to observe these effects in a 3D microenvironment and provide a better representation of cellular responses in 3D.

Laryngeal framework reconstruction using titanium mesh in glottic cancer after frontolateral vertical partial laryngectomy

OBJECTIVES

To investigate the feasibility and efficacy of laryngeal framework reconstruction using titanium mesh in patients with glottic cancer after frontolateral vertical partial laryngectomy.

STUDY DESIGN

Prospective study.

METHODS

Defect of laryngeal framework, caused by frontolateral vertical partial laryngectomy in nine patients with T2 or T3 squamous cell carcinoma of glottic, were reconstructed with titanium mesh from 2007 to 2009. Computed tomography (CT) and fiberscopic examinations were performed at two weeks and three months postoperatively.

RESULTS

No aspiration and laryngeal stenosis was observed in the nine patients. CT scanning showed that titanium mesh was fastened well without displacement and deformity and that there was no laryngeal stenosis. Fiberscopic inspection showed that the larynx lumen was maintained well without stricture, shrinkage, and necrosis. No titanium mesh was exposed to the larynx lumen.

CONCLUSIONS

Titanium mesh was a good alternative for reconstruction of the laryngeal framework. It provided adequate structural support to maintain airway patency.

Delayed laryngotracheal reconstruction with titanium plate: report of 10 cases

BACKGROUND

Subglottic stenosis is congenital or acquired narrowing of subglottic area. The management of subglottic stenosis is still a serious surgical challenge. Although different surgical techniques are accomplished to manage the condition, no standard treatment has been presented yet.

STUDY DESIGN

Titanium mesh was used in the reconstruction of the anterior laryngotracheal wall in 10 tracheostomized patients with laryngotracheal stenosis because of prolonged intubation. The anterior laryngotracheal wall was split, followed by excision of scar tissue. After several weeks, in a second-stage performance, the titanium plate was fixed at the split edges.

RESULTS

Finally, all the patients were decanulated. However, one patient developed respiratory distress because of granulation tissue and underwent a second trial of decanulation. In one patient, the titanium plate extruded.

Use of titanium mesh in laryngotracheal reconstruction: an experimental study on rabbits

Titanium mesh may be an alternative material to be used in laryngotracheal reconstruction. Twenty New Zealand rabbits were divided into two groups. Group A underwent laryngotracheoplasty with titanium mesh-buccal mucosa-muscle complex, and Group B received auricular cartilage grafts. All animals survived without complications. The animals were killed at 60 days, and laryngotracheal regions were evaluated. There was no subglottic collapse at physiologic and supraphysiologic negative airway pressures in Group A and mild-moderate collapse in Group B. Macroscopically the average antero-posterior and lateral diameters were not statistically different among two groups. Light microscopic examination revealed no fibrosis, necrosis or new cartilage formation in both groups. Inflammation and granulation were more pronounced in Group A. The lumens in both groups were moderately obstructed. Reconstruction of the upper airway with titanium mesh may be used in very selected cases where autologous grafting materials are inadequate and unsatisfactory.

Managing obstruction of the central airways

Lung cancer is the most common cause of cancer death in Australia, Europe and the USA. Up to 20-30% of these cancers eventually affect the central airways and result in reduced quality of life, dyspnoea, haemoptysis, post-obstructive pneumonia and ultimately death. Non-malignant processes may also lead to central airway obstruction and can have similar symptoms. With the development of newer technologies, the last 20 years have seen the emergence of the field of interventional pulmonology to deal specifically with the diagnosis and management of thoracic malignancy, including obstruction of the central airways. This review discusses the pathology, pre-procedure work-up and management options for obstructing central airway lesions. Several treatment modalities exist for dealing with endobronchial pathology with local availability and expertise guiding choice of treatment. While the literature lacks large, multicentre, randomized studies defining the optimal management strategy for a given problem, there is growing evidence from numerous case studies of improved physiology, of quality of life and possibly of survival with modern interventional techniques.