Usefulness of Cross-Linked Human Acellular Dermal Matrix as an Implant for Dorsal Augmentation in Rhinoplasty

Decellularized Extracellular Matrix Scaffolds for Soft Tissue Augmentation: From Host-Scaffold Interactions to Bottlenecks in Clinical Translation

Along with a paradigm shift in looking at soft tissue fillers from space-filling to bioactive materials, decellularized extracellular matrix (DEM) fillers have gained more attention considering their superior bioactivity. However, the complex mechanisms that govern the interaction between host tissues and DEMs have been partially understood. This review first covers the mechanisms that determine immunogenicity, angiogenesis and vasculogenesis, and recellularization and remodeling after DEM implantation into host tissue, with a particular focus on related findings from filler materials. Accordingly, the review delves into the dual role of macrophages and their M1/M2 polarization paradigm to form both constructive and destructive immune responses to DEM implants. Moreover, the contribution of macrophages in angiogenesis has been elucidated, which includes but is not limited to the secretion of angiogenic growth factors and extracellular matrix (ECM) remodeling. The findings challenge the traditional view of immune cells as solely destructive entities in biomaterials and indicate their multifaceted roles in tissue regeneration. Furthermore, the review discusses how the compositional factors of DEMs, such as the presence of growth factors and matrikines, can influence angiogenesis, cell fate, and differentiation during the recellularization process. It is also shown that the biomechanical properties of DEMs, including tissue stiffness, modulate cell responses through mechanotransduction pathways, and the structural properties of DEMs, such as scaffold porosity, impact cell-cell and cell-ECM interactions. Finally, we pointed out the current clinical applications, the bottlenecks in the clinical translation of DEM biomaterials into soft tissue fillers, as well as the naïve research areas of the field.

Comparison of the efficacy of fat, cartilage, and bone grafts in traumatic and asymmetric noses

BACKGROUND

Correction of asymmetry and irregularity deformities with autologous grafts, without osteotomies, offers advantages to both plastic surgeons and patients with severe deviation. Various autologous tissues such as fat, bone, and cartilage grafts are viable options for this purpose.

OBJECTIVES

This study aimed to compare the efficacy of 3 autologous filling materials in patients with bone asymmetry.

METHODS

A retrospective evaluation was conducted on 297 patients seeking aesthetic nose surgery between 2015 and 2022. Only primary patients without prior surgery and those with bone asymmetry from trauma, with dorsum protrusion <3 mm, and without osteotomy were included. Patients were divided into fat, cartilage, and bone groups. Grafts were applied to the concave side during closed rhinoplasty, and evaluations were done 12 months after surgery by blinded plastic surgeons and patients using established assessment tools.

RESULTS

Fat, cartilage, and bone grafts were utilized in 74, 127, and 96 patients, respectively, with a mean follow-up of 19 months. The mean graft volumes were 1.0 cc (bone), 1.3 cc (cartilage), and 1.6 cc (fat). The patient self-assessment scores were 75%, 84.9%, and 86.6%, respectively. The Asher-McDade averages were 77.2%, 86.7%, and 88.4%, respectively. Cartilage and bone graft results were statistically similar in patients' self-evaluation and significantly higher than those of fat grafts. Blinded assessments showed no significant difference between the cartilage and bone groups.

CONCLUSION

Placing autologous grafts on the concave side for patients with minimal nasal bone protrusion (<3 mm) yields successful results. Cartilage grafts offer advantages in volume, result estimation, and preparation time, making them suitable for larger patient cohorts.

The current techniques in dorsal augmentation rhinoplasty: a comprehensive review

BACKGROUND

An essential aspect of rhinoplasty is the enhancement of the nasal dorsal contour by performing dorsal augmentation (DA) rhinoplasty. A wide range of techniques are available for DA as the demand for aesthetic nasal refinement grows. This review aims to provide a comprehensive overview of the current techniques used in DA rhinoplasty.

MAIN BODY

Research articles on DA rhinoplasty techniques were identified through a comprehensive literature search. Scopus, PubMed, and Web of Science were used as electronic databases. Each database was searched for articles published since its inception. DA rhinoplasty techniques were examined in this literature review. Methodological quality was assessed for the selected studies, and data was extracted to examine materials used, surgical approaches, and reported outcomes for each technique. Various DA methods, including autologous grafts and synthetic implants, are examined in-depth in this review. Comparing approaches can help better understand their respective advantages and limitations.

CONCLUSION

A wealth of techniques is available for DA rhinoplasty, each with advantages. Patients' nasal anatomy, desired outcomes, and potential risks must be considered by surgeons when determining their surgical approach. DA methods continue to evolve rapidly, creating a need for a thorough understanding of the current landscape to make informed decisions.

Use of human acellular dermal matrix in rhinoplasty: a systematic review of the literature and meta-analysis

Alloplastic implants such as acellular dermal matrix (ADM) have been used for various aesthetic and reconstructive purposes since the 1990s. Rhinoplasty addresses both aesthetic and functional nasal impairments, often involving the adoption of grafting materials. Currently, autologous grafts, such as those using septal cartilage, are the gold standard. However, they pose the risk of donor site morbidity, technical challenges, and additional operative time. We review total complications, resorption/re-operation and success rates associated with the use of ADM in rhinoplasty. A literature search was conducted on PubMed, Prospero, DynaMed, DARE, EMBASE and COCHRANE databases. (Registry: CRD42023428019). A total of 462 patients from 15 studies were included, the mean (range) age was 30 (12-65) years, with a female-to-male ratio of 2:1. The most common indications for ADM were for cosmetic (35%, n = 163) and functional rhinoplasty (5%, n = 24). The most common type of ADM used was Alloderm (46%, n = 211). The most common indication for ADM was dorsal nasal augmentation (68%, n = 314). Eleven patients (2%) required revision surgery. The pooled success of ADM in rhinoplasty was 96% (95% CI 94 to 99, p = 0.93; I2 = 0%). 2% of patients developed postoperative complications and no statistically significant difference was seen in complications or success rates when comparing the different types of ADM. ADM in rhinoplasty was associated with fewer complications and re-operation rates, and similar if not less resorption compared to traditional autografts. Therefore, it can be a viable alternative to current autologous grafts in rhinoplasty surgery.

Safety and Efficacy of Autologous Cartilage Graft in Augmentation Rhinoplasty

Augmentation rhinoplasty or commonly known as "nose jobs" is one of the most common plastic surgical procedures aimed to improve cosmetic appearance. This procedure is considerably safer, less time consuming with faster recovery and immediate cosmetic effect. This procedure needs of highly experienced and well-trained plastic surgeon. According to facial analysis you can select the type of rhinoplasty. Open discussion with the patient to select appropriate surgical technique and its possible risks with your plastic surgeon to ensure the highest level of safety and satisfaction. Autologous grafting materials are safe, efficient and also the first choice for rhinoplasty due to it can survive without a vascular supply, the resorption rate of cartilage is much lower than that of a bone graft. Autologous grafting materials are stable and resistant to infection and extrusion over time so, they are successfully used for dorsal augmentation. To perform successful augmentation rhinoplasty, surgeons should be highly experienced and well-trained and augmentation materials that are currently available and understand their risks, benefits and uses. Autologous cartilage graft regarded as the graft of choice in augmentation rhinoplasty because of their lower rate of infection, rejection, resorption, extrusion, donor site morbidity, easy reshaping.

The Use of Acellular Human Dermis as a Dorsal Camouflaging Graft in Rhinoplasty

Background: Acellular human dermis (AHD) has many uses in rhinoplasty, but its long-term use as a camouflaging graft has not been adequately described. Objective: To measure the long-term outcomes (infections/contour irregularities) of AHD used as a camouflage graft in rhinoplasty. Methods: A retrospective study of 91 patients who underwent rhinoplasty requiring AHD as a camouflage graft for a 20-year time period (2000-2020) was performed. Complications, revisions, and long-term outcomes were assessed. Surgical technique for AHD use as a dorsal and tip camouflage graft was described in detail and illustrated using intraoperative photography. Results: Of the 91 patients who required AHD in their rhinoplasties, 70 (77%) were performed in revision cases to thicken thinned and scarred skin envelopes. Only 1% had postoperative contour problems that were attributable to AHD, and only 3% had resorption of the AHD. Four percent had postoperative infections, all of which resolved with a single course of oral antibiotics. Patients were followed a mean of 3.8 years. Conclusions: AHD can be a safe, effective, and readily available option for use in thickening the nasal skin envelope in rhinoplasty.

Acellular dermal matrix in reconstructive surgery: Applications, benefits, and cost

Modern tissue engineering has made substantial advancements that have revolutionized plastic surgery. Acellular dermal matrix (ADM) is an example that has gained considerable attention recently. ADM can be made from humans, bovines, or porcine tissues. ADM acts as a scaffold that incorporates into the recipient tissue. It is gradually infiltrated by fibroblasts and vascularized. Fortunately, many techniques have been used to remove cellular and antigenic components from ADM to minimize immune system rejection. ADM is made of collagen, fibronectin, elastin, laminin, glycosaminoglycans, and hyaluronic acid. It is used in critical wounds (e.g., diabetic wounds) to protect soft tissue and accelerate wound healing. It is also used in implant-based breast reconstruction surgery to improve aesthetic outcomes and reduce capsule contracture risk. ADM has also gained attention in abdominal and chest wall defects. Some studies have shown that ADM is associated with less erosion and infection in abdominal hernias than synthetic meshes. However, its higher cost prevents it from being commonly used in hernia repair. Also, using ADM in tendon repair (e.g., Achilles tendon) has been associated with increased stability and reduced rejection rate. Despite its advantages, ADM might result in complications such as hematoma, seroma, necrosis, and infection. Moreover, ADM is expensive, making it an unsuitable option for many patients. Finally, the literature on ADM is insufficient, and more research on the results of ADM usage in surgeries is needed. This article aims to review the literature regarding the application, Benefits, and costs of ADM in reconstructive surgery.

Current Practices in Dorsal Augmentation Rhinoplasty

BACKGROUND

Dorsal augmentation rhinoplasty addresses the aesthetic and functional impairments caused by a deficient nasal dorsum. Augmentation rhinoplasty can be performed using a variety of different surgical techniques and grafting materials that all have distinct advantages and disadvantages.

METHODS

Grafting materials have unique characteristics, uses, and safety profiles. A detailed overview of various grafting materials and their uses, risks, and benefits is provided.

RESULTS

Autologous grafting materials include septal cartilage, auricular cartilage, and costal cartilage. These donor sites can provide various amounts of en bloc or diced cartilage. Alternatively, bone may be used when strong structural stability is required, and soft tissue may be used to fill mild to moderate defects. Homologous grafts (e.g., irradiated and nonirradiated rib) and acellular dermal matrices are alternatives to autologous graft with many similar advantages and no need for an additional surgical site. Lastly, alloplastic implants may be successfully used for dorsal augmentation if both patient and surgeon understand their associated risks.

CONCLUSION

To perform successful dorsal augmentation, surgeons should be familiar with the wide variety of operative approaches and augmentation materials that are currently available and understand their risks, benefits, and uses.

Treatment of Human Immunodeficiency Virus-Associated Facial Lipoatrophy With Hyaluronic Acid Filler Mixed With Micronized Cross-Linked Acellular Dermal Matrix

BACKGROUND

Human immunodeficiency virus (HIV)-associated facial lipoatrophy (FLA) is a stigmatizing side effect associated with the use of highly active antiretroviral therapy. We sought to evaluate the safety and efficacy of the hyaluronic acid filler mixed with micronized cross-linked acellular dermal matrix (HA/MADM) in HIV-associated FLA.

METHODS

We conducted an open-label safety and efficacy study in patients with HIV-associated FLA. Fourteen patients received single injection of the HA/MADM, and 13 patients completed the 24-week follow-up evaluation. Treatment efficacy, safety, and patient and physician satisfaction were evaluated. Repeated measure analysis of variance with post-hoc analysis with the Wilcoxon signed rank test was performed to compare and incorporate parameters at each time point.

RESULTS

All 13 patients maintained a significant improvement of the Carruthers Lipoatrophy Severity Scale grade throughout the study period, along with improvement of the depressed volume due to lipoatrophy measured using a three-dimensional camera system. More than 80% of patients and physicians were satisfied with the treatment, and no treatment-related adverse events were reported, except for one case of transient subcutaneous nodule formation.

CONCLUSION

Our study findings suggest that injectable HA/MADM is a potentially effective and safe treatment option for treating HIV-positive patients with FLA.

Clinical applications of acellular dermal matrices: A review

INTRODUCTION

The extracellular matrix (ECM) plays an integral role in wound healing. It provides both structure and growth factors that allow for the organised cell proliferation. Large or complex tissue defects may compromise host ECM, creating an environment that is unfavourable for the recovery of anatomical function and appearance. Acellular dermal matrices (ADMs) have been developed from a variety of sources, including human (HADM), porcine (PADM) and bovine (BADM), with multiple different processing protocols. The objective of this report is to provide an overview of current literature assessing the clinical utility of ADMs across a broad spectrum of applications.

METHODS

PubMed, MEDLINE, EMBASE, Scopus, Cochrane and Web of Science were searched using keywords 'acellular dermal matrix', 'acellular dermal matrices' and brand names for commercially available ADMs. Our search was limited to English language articles published from 1999 to 2020 and focused on clinical data.

RESULTS

A total of 2443 records underwent screening. After removing non-clinical studies and correspondence, 222 were assessed for eligibility. Of these, 170 were included in our synthesis of the literature. While the earliest ADMs were used in severe burn injuries, usage has expanded to a number of surgical subspecialties and procedures, including orthopaedic surgery (e.g. tendon and ligament reconstructions), otolaryngology, oral surgery (e.g. treating gingival recession), abdominal wall surgery (e.g. hernia repair), plastic surgery (e.g. breast reconstruction and penile augmentation), and chronic wounds (e.g. diabetic ulcers).

CONCLUSION

Our understanding of ADM's clinical utility continues to evolve. More research is needed to determine which ADM has the best outcomes for each clinical scenario.

LAY SUMMARY

Large or complex wounds present unique reconstructive and healing challenges. In normal healing, the extracellular matrix (ECM) provides both structural and growth factors that allow tissue to regenerate in an organised fashion to close the wound. In difficult or large soft-tissue defects, however, the ECM is often compromised. Acellular dermal matrix (ADM) products have been developed to mimic the benefits of host ECM, allowing for improved outcomes in a variety of clinical scenarios. This review summarises the current clinical evidence regarding commercially available ADMs in a wide variety of clinical contexts.

Effectiveness of cross-linked human acellular dermal matrix in primary and revision augmentation rhinoplasty

BACKGROUND

Among the materials used for dorsal augmentation rhinoplasty (DAR), cross-linked human acellular dermal matrix (ADM) has been claimed for its low risk of infection and extrusion. The aim of this study was to compare the effectiveness of ADM in subjects undergoing primary versus revision dorsal augmentation rhinoplasties.

METHODS

Using a retrospective cohort study design, the investigators enrolled a cohort set of DAR patients operated by a single surgeon during a 65-month interval. The predictor variable was the treatment group (primary or revision DAR). The main outcome variables were postoperative changes with regard to the degree of augmentation (ratio of the dorsal height [DH] and radix height [RH] to the nasal length) and patients' and surgeons' satisfaction with the aesthetic and functional results. Other study variables were grouped into the following categories: demographic, surgical, and pathological. Descriptive, uni-, and bivariate statistics were computed using P ≤ 0.05 as a cutoff value.

RESULTS

The study cohort comprised 145 subjects (75.2% with primary DAR; 39.3% females) with a mean age of 30.7 ± 9.4 years (range, 19-58). DAR was linked to the significant changes in DH and RH in both the treatment groups. Comparison of the two groups revealed that there was no significant difference in DH and RH between both the groups. Surgeons' and patients' satisfaction rates were comparable between the two surgery groups, neither of which experienced serious complications. Microscopic findings of the removed ADM showed abundant collagen tissue with newly formed vessels without signs of foreign body reaction.

CONCLUSION

Despite significant differences in patient characteristics (age; number of osteotomy, tip plasty, and hump reduction surgeries), the results of this study suggest that ADM can be used in both primary and revision DAR, with minimal complications.

The use of human acellular dermal matrices in advanced wound healing and surgical procedures: State of the art

Wound closure after post-traumatic injuries and/or localized at peculiar body sites (head-and-neck, oral cavity, legs) are particularly challenging and can often be delayed due to local and systemic factors. In case of deep wounds and/or hard-to-heal wounds, grafting of dermal acellular matrices (ADM) is often needed. Though a great variety of synthetic and semisynthetic dermal and skin equivalents are available, viable human dermis, is still considered the most physiological alternative to replace the loss of autologous dermis, by acting as a physiological scaffold that add structural support to soft tissues. To date, human ADMs (hADMs) have been employed in the reconstruction of skin defects affecting almost all body sites, ranging from visceral sites to the skin and subcutaneous tissues. This review aims to investigate the use of hADM at different body sites and their peculiar advantages. A literature search was using the search terms "acellular dermal matrices", "dermal regeneration", "advances wound healing", "human acellular dermal matrices surgery". A total of 50 out of 150 papers was included. Based on the current body if evidence, hADMs appear to bring several advantages, such as: protection of deep structures (eg, tendons, bones, cartilage and nerves); stimulation of a functional new dermis (rather than a scar); reduction of wound closure time; control of pain and exudate. Finally, hADMs may represent the best treatment option for hard-to-heal wound not only in terms of efficacy and patient satisfaction bout also in terms of sanitary costs, especially across Europe, where hADMs cannot be commercialized as medical devices.

Nasal alar rim redraping method to prevent alar retraction in rhinoplasty for Asian men: A retrospective case series

BACKGROUND

For an attractive and natural tip contour in Asian rhinoplasty, insertion of a nasal implant and reinforcement of the cartilaginous framework are essential. However, scar contracture, which often results from augmentation with implant insertion and inadequate soft tissue coverage of the framework, is one of the most common causes of alar retraction. This study reports a novel method of redraping soft tissue along the alar rim to prevent alar retraction in Asians.

METHODS

Twenty young Asian men who underwent primary rhinoplasty with septoplasty were retrospectively reviewed. After the usual rhinoplasty procedures, alar rim redraping was conducted for the soft tissue along the transcolumellar and bilateral infracartilaginous incisions. The longest axis of the nostril (a) and the height of the nostril from that axis (b) were measured in anterior-posterior and lateral views. The preoperative and postoperative ratios (b/a) were analyzed using the paired t-test.

RESULTS

All 20 patients showed natural contours of the nasal tip, nostrils, and alae after a mean follow-up of 53.6 weeks (range, 52-60 weeks). The ratio of the nostril axes significantly decreased postoperatively in all patients except one, by an average of 11.08%±6.52% in the anterior-posterior view and 17.74%±8.49% in the lateral view (P<0.01). There were no complications, including asymmetry, contracture, subdermal plexus injury, flap congestion, or infection.

CONCLUSIONS

A quantitative analysis of alar retraction by evaluating the ratio of nostril axes showed that alar rim redraping is a simple and effective adjuvant technique for preventing alar retraction in rhinoplasty for young Asian men.

Comparison of Volume Retention and Biocompatibility of Acellular Dermal Matrix/Hyaluronic Acid Filler to Autologous Fat Grafts in a Mouse Model

BACKGROUND

Although fat grafting has become a widely used technique in aesthetic and reconstructive surgeries, resorption is still a challenge. Micronized acellular dermal matrix (ADM) has been considered as a stable, biocompatible soft tissue coverage material that can be used as a volume filler. Here, we compared the bioacceptance and sustainability of ADM hyaluronic acid (HA) filler with human fat graft in a mouse model.

METHODS

Harvested human fat and ADM/HA filler were injected randomly on the dorsal side of mice. Thirty-two mice were analyzed over a 7-week period with respect to volume, weight and microscopic evaluations with hematoxylin and eosin (H&E), epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) staining.

RESULTS

The volume and weight were maintained at 80% and 83%, respectively, in the ADM/HA filler group and 56.5% and 49.7%, respectively, in the fat-grafted group by the 7th week. There were no significant microscopic differences in inflammatory changes and granulation via H&E staining. At 1 and 2 weeks, EGF and VEGF immunostaining intensity scores were lower in the ADM/HA filler group. At 7 weeks, there were no significant differences in immunostaining intensity scores between the two groups.

CONCLUSIONS

During the 7-week experimental period, the ADM/HA filler showed no foreign body reaction and the proper volume was well maintained. This suggests that the ADM/HA filler can possibly be used in small amounts as an alternative to autologous fat grafts.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authorshttp://www.springer.com/00266.

Camouflage of the Nasal Dorsum in Thin-Skinned Patients with Diced Cartilage Combined with a New Cross-Linked Hyaluronan (NCH) Gel and Blood: A New Method

INTRODUCTION

Nasal dorsum irregularities after rhinoplasty are still one of the most common complaints among both surgeons and patients. In this study, we used a new cross-linked hyaluronan (NCH) gel and blood mixture as the stabilisation scaffold. Diced cartilage combined with the NCH gel and blood mixture was used for nasal dorsum camouflage.

PATIENTS AND METHODS

Fifty-two thin-skinned patients (29 females and 23 males) underwent primary rhinoplasty including nasal dorsum enhancement with diced cartilage combined with the NCH gel and blood mixture. The cartilage tissue was diced into small pieces; then, 1 cc NCH gel and blood were added into diced cartilage. The mixture was delivered onto the nasal dorsum via dorsal retractor.

RESULTS

After 1 year of follow-up, there were no irregularities in the nasal dorsum area observed, nor any displacement or absorbance of the camouflage material. No complications occurred.

CONCLUSION

The use of diced cartilage combined with the NCH gel and blood is an effective, simple and safe method for nasal dorsum camouflage in thin-skinned patients in rhinoplasty. The NCH gel within the mixed graft also reduces adhesions at the osteotomy lines.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .