Nasal Valve Considerations in Mohs Reconstruction

Airway obstruction is a possible sequela following reconstruction of the nose after Mohs excision of skin cancers. While the principles and goals of tissue replacement after Mohs micrographic surgery are well-established, less attention has been paid to the evaluation of the nasal airway after reconstruction. Reconstructive planning begins with understanding the risk factors associated with the development of nasal valve compromise. Several approaches to prevent and correct nasal valve narrowing will be reviewed as part of a unified reconstructive plan for patients after skin cancer excision in high risk areas.

Decision Making in Nasal Reconstruction: When to Use the Forehead Flap?

In this review, the paramedian forehead flap indications and uses are reviewed, specifically examining clinical situations where patient selection is important. In these settings, a preoperative discussion with a patient regarding surgical expectations and goals in the setting of their defect is paramount. The authors review the literature regarding the psychosocial aspects of major nasal reconstruction and review preoperative discussion points that are key to a well-informed patient and improved patient satisfaction through the nasal reconstructive process.

Reducing Risks of Graft Failure for Composite Skin–Cartilage Grafts

Facial skin defects pose unique challenges for the reconstructive surgeon. Aesthetically complex areas involving a free margin-such as the ear, eyelid, columella, columella-lobule interface, soft tissue triangle, alar rim, and internal nasal lining-are particularly demanding, as secondary soft tissue contracture in these locations can lead to a very poor cosmetic outcome. In these cases, composite grafts offer an ideal combination of soft tissue coverage and structural rigidity, all accomplished in a single-stage surgery. Composite grafts are often underused in facial reconstructive surgery due to the tenuous blood supply and high reported rates of graft failure.

Surgical Techniques Following Free Cartilage Grafting

BACKGROUND

Reconstruction of surgical defects with free cartilage grafts poses unique challenges.

OBJECTIVES

To characterize surgical techniques following free cartilage grafting.

MATERIALS AND METHODS

A literature review was performed using the Embase, PubMed Medline, Cochrane Library, ClinicalTrials.gov, and Web of Science databases from inception to May 21, 2021. Studies describing free cartilage grafts harvested from the ear or nose under local anesthesia, specifically for reconstruction of facial surgical defects, were selected for inclusion. Only surgical defects resulting from tumor resection were included.

RESULTS

In total, 34 studies involving 713 patients with 723 surgical defects met inclusion criteria. The mean age of patients was 63.3 ± 10.4 years. Free cartilage grafts were most commonly harvested from the ear (93.1%). The most common recipient site was the nose (90.3%), followed by the lower eyelid (6.7%) and ear (3.0%).

CONCLUSION

Free cartilage grafts are an effective reconstructive option for patients with deep or cartilaginous defects that have compromised structural support on the nose, ear, or eyelid.

Three-Dimensional Bioprinting Scaffolding for Nasal Cartilage Defects: A Systematic Review

BACKGROUND

In recent years, three-dimensional (3D)-printing of tissue-engineered cartilaginous scaffolds is intended to close the surgical gap and provide bio-printed tissue designed to fit the specific geometric and functional requirements of each cartilage defect, avoiding donor site morbidity and offering a personalizing therapy.

METHODS

To investigate the role of 3D-bioprinting scaffolding for nasal cartilage defects repair a systematic review of the electronic databases for 3D-Bioprinting articles pertaining to nasal cartilage bio-modelling was performed. The primary focus was to investigate cellular source, type of scaffold utilization, biochemical evaluation, histological analysis, in-vitro study, in-vivo study, animal model used, length of research, and placement of experimental construct and translational investigation.

RESULTS

From 1011 publications, 16 studies were kept for analysis. About cellular sources described, most studies used primary chondrocyte cultures. The cartilage used for cell isolation was mostly nasal septum. The most common biomaterial used for scaffold creation was polycaprolactone alone or in combination. About mechanical evaluation, we found a high heterogeneity, making it difficult to extract any solid conclusion. Regarding biological and histological characteristics of each scaffold, we found that the expression of collagen type I, collagen Type II and other ECM components were the most common patterns evaluated through immunohistochemistry on in-vitro and in-vivo studies. Only two studies made an orthotopic placement of the scaffolds. However, in none of the studies analyzed, the scaffold was placed in a subperichondrial pocket to rigorously simulate the cartilage environment. In contrast, scaffolds were implanted in a subcutaneous plane in almost all of the studies included.

CONCLUSION

The role of 3D-bioprinting scaffolding for nasal cartilage defects repair is growing field. Despite the amount of information collected in the last years and the first surgical applications described recently in humans. Further investigations are needed due to the heterogeneity on mechanical evaluation parameters, the high level of heterotopic scaffold implantation and the need for quantitative histological data.

Long-term in vivo integrity and safety of 3D-bioprinted cartilaginous constructs

Long-term stability and biological safety are crucial for translation of 3D-bioprinting technology into clinical applications. Here, we addressed the long-term safety and stability issues associated with 3D-bioprinted constructs comprising a cellulose scaffold and human cells (chondrocytes and stem cells) over a period of 10 months in nude mice. Our findings showed that increasing unconfined compression strength over time significantly improved the mechanical stability of the cell-containing constructs relative to cell-free scaffolds. Additionally, the cell-free constructs exhibited a mean compressive stress and stiffness (compressive modulus) of 0.04 ± 0.05 MPa and 0.14 ± 0.18 MPa, respectively, whereas these values for the cell-containing constructs were 0.11 ± 0.08 MPa (p = .019) and 0.53 ± 0.59 MPa (p = .012), respectively. Moreover, histomorphologic analysis revealed that cartilage formed from the cell-containing constructs harbored an abundance of proliferating chondrocytes in clusters, and after 10 months, resembled native cartilage. Furthermore, extension of the experiment over the complete lifecycle of the animal model revealed no signs of ossification, fibrosis, necrosis, or implant-related tumor development in the 3D-bioprinted constructs. These findings confirm the in vivo biological safety and mechanical stability of 3D-bioprinted cartilaginous tissues and support their potential translation into clinical applications.

Comparative Study of Functional Nasal Reconstruction Using Structural Reinforcement

Importance

Nasal reconstruction after Mohs surgery is a unique challenge in that it must satisfy both functional and aesthetic goals. Despite some advocacy in the literature for using structural reinforcement to achieve both functional and aesthetic outcomes in soft-tissue reconstruction, no study has validated this claim by comparing reconstruction with and without structural support.

Objective

To evaluate the effectiveness of and need for structural reinforcement when reconstructing the nasal alar and sidewall subunits.

Design, Setting, and Participants

This study was a retrospective review of the medical records of 190 patients 18 years or older who underwent nasal reconstruction after Mohs surgery in a tertiary care academic center between January 1, 2013, and August 31, 2015. Data on each patient included demographics, comorbidities, smoking status, details of the lesion, size of defect, subunits involved, and reconstructive technique. Patients were divided into 2 cohorts composed of those who had reconstruction with structural reinforcement (ie, cartilage grafting or suspension suture) and those with only soft-tissue reconstruction. Patients with nasal obstruction from the functional collapse of the reconstructed area and no history of nasal obstruction were included (n = 38). Patients who had a follow-up of less than 2 months, no alar or sidewall involvement, nasal obstruction secondary to turbinate hypertrophy, septal deflection or other nonstructural causes, and incomplete documentation for analysis were excluded (n = 102).

Main Outcomes and Measures

Rates of postoperative nasal obstruction secondary to nasal sidewall collapse and need for revision surgery.

Results

Of the 38 patients who met the inclusion criteria, 22 were men and 16 were women with a mean (range) age of 64.5 (35-92) years. Twenty-three patients (61%) underwent reconstruction by a facial plastic surgeon and 15 (39%) by 2 dermatologic surgeons. Three (8%) underwent reconstruction without reinforcement and experienced postoperative nasal obstruction. The mean size of reconstructed defects that resulted in nasal valve collapse was 2.1 cm in diameter (range, 1.2-2.6 cm). Defect size was associated with incidence of postoperative nasal obstruction. For defects greater than 1.2 cm in diameter, patients reconstructed without reinforcement had a statistically significant increase of nasal obstruction secondary to functional nasal collapse compared with patients reconstructed with reinforcement (3 of 14 [21%] vs 0 of 17; 95% CI, 0.005-0.358; P = .04).

Conclusions and Relevance

Nasal defects greater than 1.2 cm in diameter and involving the alar and sidewalls were associated with lower incidence of postoperative nasal obstruction when a structural reinforcement technique was used in reconstruction. The findings of this study support the structural reinforcement of the nasal functional subunits during Mohs reconstructive surgery to achieve optimal outcomes.

Level of Evidence

3.

Engineered autologous cartilage tissue for nasal reconstruction after tumour resection: an observational first-in-human trial

BACKGROUND

Autologous native cartilage from the nasal septum, ear, or rib is the standard material for surgical reconstruction of the nasal alar lobule after two-layer excision of non-melanoma skin cancer. We assessed whether engineered autologous cartilage grafts allow safe and functional alar lobule restoration.

METHODS

In a first-in-human trial, we recruited five patients at the University Hospital Basel (Basel, Switzerland). To be eligible, patients had to be aged at least 18 years and have a two-layer defect (≥50% size of alar subunit) after excision of non-melanoma skin cancer on the alar lobule. Chondrocytes (isolated from a 6 mm cartilage biopsy sample from the nasal septum harvested under local anaesthesia during collection of tumour biopsy sample) were expanded, seeded, and cultured with autologous serum onto collagen type I and type III membranes in the course of 4 weeks. The resulting engineered cartilage grafts (25 mm × 25 mm × 2 mm) were shaped intra-operatively and implanted after tumour excision under paramedian forehead or nasolabial flaps, as in standard reconstruction with native cartilage. During flap refinement after 6 months, we took biopsy samples of repair tissues and histologically analysed them. The primary outcomes were safety and feasibility of the procedure, assessed 12 months after reconstruction. At least 1 year after implantation, when reconstruction is typically stabilised, we assessed patient satisfaction and functional outcomes (alar cutaneous sensibility, structural stability, and respiratory flow rate).

FINDINGS

Between Dec 13, 2010, and Feb 6, 2012, we enrolled two women and three men aged 76-88 years. All engineered grafts contained a mixed hyaline and fibrous cartilage matrix. 6 months after implantation, reconstructed tissues displayed fibromuscular fatty structures typical of the alar lobule. After 1 year, all patients were satisfied with the aesthetic and functional outcomes and no adverse events had been recorded. Cutaneous sensibility and structural stability of the reconstructed area were clinically satisfactory, with adequate respiratory function.

INTERPRETATION

Autologous nasal cartilage tissues can be engineered and clinically used for functional restoration of alar lobules. Engineered cartilage should now be assessed for other challenging facial reconstructions.

FUNDING

Foundation of the Department of Surgery, University Hospital Basel; and Krebsliga beider Basel.