In vitro extracellular matrix accumulation of nasal and articular chondrocytes for intervertebral disc repair

Chondrocyte based regenerative therapies for intervertebral disc repair such as Autologous Disc Cell Transplantation (ADCT, CODON) and allogeneic juvenile chondrocyte implantation (NuQu^®, ISTO Technologies) have demonstrated good outcomes in clinical trials. However concerns remain with the supply demand reconciliation and issues surrounding immunoreactivity which exist for allogeneic-type technologies. The use of stem cells is challenging due to high growth factor requirements, regulatory barriers and differentiation towards a stable phenotype. Therefore, there is a need to identify alternative non-disc cell sources for the development and clinical translation of next generation therapies for IVD regeneration. In this study, we compared Nasal Chondrocytes (NC) as a non-disc alternative chondrocyte source with Articular Chondrocytes (AC) in terms of cell yield, morphology, proliferation kinetics and ability to produce key extracellular matrix components under 5% and 20% oxygen conditions, with and without exogenous TGF-β supplementation. Results indicated that NC maintained proliferative capacity with high amounts of sGAG and lower collagen accumulation in the absence of TGF-β supplementation under 5% oxygen conditions. Importantly, osteogenesis and calcification was inhibited for NC when cultured in IVD-like microenvironmental conditions. The present study provides a rationale for the exploration of nasal chondrocytes as a promising, potent and clinically feasible autologous cell source for putative IVD repair strategies.

Analysis of the development of the nasal septum and measurement of the harvestable septal cartilage in koreans using three-dimensional facial bone computed tomography scanning

Background

The septal cartilage is the most useful donor site for autologous cartilage graft material in rhinoplasty. For successful nasal surgery, it is necessary to understand the developmental process of the nasal septum and to predict the amount of harvestable septal cartilage before surgery.

Methods

One hundred twenty-three Korean patients who underwent three-dimensional (3D) facial bone computed tomography (CT) were selected for evaluation of the midsagittal view of the nasal septum. Multiple parameters such as the area of each component of the nasal septum and the amount of harvestable septal cartilage were measured using Digimizer software.

Results

The area of the total nasal septum showed rapid growth until the teenage years, but thereafter no significant change throughout the lifetime. However, the development of the septal cartilage showed a gradual decline due to ossification changes with aging after puberty in spite of a lack of change in the total septal area. The area of harvestable septal cartilage in young adults was 549.84±151.26 mm² and decreased thereafter with age.

Conclusions

A 3D facial bone CT scan can provide valuable information on the septal cartilage graft before rhinoplasty. Considering the developmental process of the septal cartilage identified in this study, septal surgery should not be performed until puberty due to the risk of nasal growth impairment. Furthermore, in elderly patients who show a decreased cartilage area due to ossification changes, septal cartilage harvesting should be performed carefully due to the risk of saddle nose deformity.

Midface and upper airway dysgenesis in FGFR2-related craniosynostosis involves multiple tissue-specific and cell cycle effects

Midface dysgenesis is a feature of more than 200 genetic conditions in which upper airway anomalies frequently cause respiratory distress, but its etiology is poorly understood. Mouse models of Apert and Crouzon craniosynostosis syndromes exhibit midface dysgenesis similar to the human conditions. They carry activating mutations of Fgfr2, which is expressed in multiple craniofacial tissues during development. Magnetic resonance microscopy of three mouse models of Apert and Crouzon syndromes revealed decreased nasal passage volume in all models at birth. Histological analysis suggested overgrowth of the nasal cartilage in the two Apert syndrome mouse models. We used tissue-specific gene expression and transcriptome analysis to further dissect the structural, cellular and molecular alterations underlying midface and upper airway dysgenesis in Apert Fgfr2^+/S252W mutants. Cartilage thickened progressively during embryogenesis because of increased chondrocyte proliferation in the presence of Fgf2 Oral epithelium expression of mutant Fgfr2, which resulted in a distinctive nasal septal fusion defect, and premature facial suture fusion contributed to the overall dysmorphology. Midface dysgenesis in Fgfr2-related craniosynostosis is a complex phenotype arising from the combined effects of aberrant signaling in multiple craniofacial tissues.

Progress of 3D Printing Techniques for Nasal Cartilage Regeneration

Once cartilage is damaged, its self-repair capacity is very limited. The strategy of tissue engineering has brought a new idea for repairing cartilage defect and cartilage regeneration. In particular, nasal cartilage regeneration is a challenge because of the steady increase in nasal reconstruction after oncologic resection, trauma, or rhinoplasty. From this perspective, three-dimensional (3D) printing has emerged as a promising technology to address the complexity of nasal cartilage regeneration, using patient's image data and computer-aided deposition of cells and biomaterials to precisely fabricate complex, personalized tissue-engineered constructs. In this review, we summarized the major progress of three prevalent 3D printing approaches, including inkjet-based printing, extrusion-based printing and laser-assisted printing. Examples are highlighted to illustrate 3D printing for nasal cartilage regeneration, with special focus on the selection of seeded cell, scaffolds and growth factors. The purpose of this paper is to systematically review recent research about the challenges and progress and look forward to the future of 3D printing techniques for nasal cartilage regeneration.Level of Evidence III 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 Authors https://www.springer.com/00266 .

The Clinical Analysis of the Nasal Septal Cartilage by Measurement Using Computed Tomography

BACKGROUND

The nasal septal cartilage is often used as a donor graft in rhinoplasty operations but can vary widely in size across the patient population. As such, preoperative estimation of the cartilaginous area is important for patient counseling as well as operating planning. We aim to estimate septal cartilage area by using facial computed tomography (CT) studies.

METHODS

The study was performed using facial CT images taken from 200 patients between January 2012 to July 2015. Using the mid-sagittal image, the boundary of cartilaginous septum was delineated from soft tissue using the mean difference in signal intensity (or brightness). The area within this boundary was calculated. The calculated area for septal cartilage was then compared across age groups and sexes.

RESULTS

Overall, the mean area of nasal septal cartilage was 8.18 cm² with the maximum of 12.42 cm² and the minimum of 4.89 cm². The cartilage areas were measured to be larger in men than in women (p<0.05). The area decreased with advancing age (p<0.05).

CONCLUSION

Measuring the size of septal cartilage using brightness difference is more precise and reliable than previously reported methods. This method can be utilized as the standard for prevention of postoperative complication.

Effectiveness of caudal septal extension graft application in endonasal septoplasty

Introduction

Septal deviation is a common disease seen in daily otorhinolaryngology practice and septoplasty is a commonly performed surgical procedure. Caudal septum deviation is also a challenging pathology for ear, nose, and throat specialists. Many techniques are defined for caudal septal deviation.

Objective

To evaluate the effectiveness of caudal septal extension graft (CSEG) application in patients who underwent endonasal septoplasty for a short and deviated nasal septum.

Methods

Forty patients with nasal septal deviation, short nasal septum, and weak nasal tip support who underwent endonasal septoplasty with or without CSEG placement between August 2012 and June 2013 were enrolled in this study. Twenty patients underwent endonasal septoplasty with CSEG placement. The rest of the group, who rejected auricular or costal cartilage harvest for CSEG placement, underwent only endonasal septoplasty without any additional intervention. Using the Nasal Obstruction Symptom Evaluation (NOSE) and Rhinoplasty Outcome Evaluation (ROE) questionnaires, pre- and post-operative acoustic rhinometer measurements were evaluated to assess the effect of CESG placement on nasal obstruction.

Results

In the control group, preoperative and postoperative minimal cross-sectional areas (MCA1) were 0.44 ± 0.10 cm² and 0.60 ± 0.11 cm², respectively (p < 0.001). In the study group, pre- and postoperative MCA1 values were 0.45 ± 0.16 cm² and 0.67 ± 0.16 cm², respectively (p < 0.01). In the control group, the nasal cavity volume (VOL1) value was 1.71 ± 0.21 mL preoperatively and 1.94 ± 0.17 mL postoperatively (p < 0.001). In the study group, pre- and postoperative VOL1s were 1.72 ± 0.15 mL and 1.97 ± 0.12 mL, respectively (p < 0.001). Statistical analysis of postoperative MCA1 and VOL1 values in the study and the control groups could not detect any significant intergroup difference (p = 0.093 and 0.432, respectively). In the study group, mean nasolabial angles were 78.15 ± 4.26° and 90.70 ± 2.38°, respectively (p < 0.001).

Conclusion

Endonasal septoplasty with CESG placement is an effective surgical procedure with minimal complication rate for subjects who have a deviated, short nasal septum and weak nasal tip support.

Compressive and tensile mechanical properties of the porcine nasal septum

The expanding nasal septal cartilage is believed to create a force that powers midfacial growth. In addition, the nasal septum is postulated to act as a mechanical strut that prevents the structural collapse of the face under masticatory loads. Both roles imply that the septum is subject to complex biomechanical loads during growth and mastication. The purpose of this study was to measure the mechanical properties of the nasal septum to determine (1) whether the cartilage is mechanically capable of playing an active role in midfacial growth and in maintaining facial structural integrity and (2) if regional variation in mechanical properties is present that could support any of the postulated loading regimens. Porcine septal samples were loaded along the horizontal or vertical axes in compression and tension, using different loading rates that approximate the in vivo situation. Samples were loaded in random order to predefined strain points (2-10%) and strain was held for 30 or 120 seconds while relaxation stress was measured. Subsequently, samples were loaded until failure. Stiffness, relaxation stress and ultimate stress and strain were recorded. Results showed that the septum was stiffer, stronger and displayed a greater drop in relaxation stress in compression compared to tension. Under compression, the septum displayed non-linear behavior with greater stiffness and stress relaxation under faster loading rates and higher strain levels. Under tension, stiffness was not affected by strain level. Although regional variation was present, it did not strongly support any of the suggested loading patterns. Overall, results suggest that the septum might be mechanically capable of playing an active role in midfacial growth as evidenced by increased compressive residual stress with decreased loading rates. However, the low stiffness of the septum compared to surrounding bone does not support a strut role. The relatively low stiffness combined with high stress relaxation under fast loading rates suggests that the nasal septum is a stress dampener, helping to absorb and dissipate loads generated during mastication.

Do the upper lateral nasal cartilages exist? The concept of septolateral cartilages

BACKGROUND

In the cartilaginous nose, classical surgical anatomy describes 2 triangular upper lateral cartilages (ULCs) framing the lateral sides of the mid-third of the nasal pyramid, which articulate with to the superior edge of the quadrangular cartilage (QC) of the nasal septum. This anatomic arrangement in 3 distinct cartilage parts is, however, controversial.

OBJECTIVE

The present study aimed to describe the articulation between the ULCs and the QC, avoiding dissection artefacts.

MATERIALS AND METHODS

Six nasal pyramids were taken in monobloc from fresh cadavers and imaged on micro-MRI with 0.4mm slice thickness. Images were interpreted jointly by 2 head and neck surgeons and a radiologist.

RESULTS

The cartilage skeleton supporting the mid-third of the nasal dorsum in all specimens presented as 2 septal plates backing onto the midline and curving on either side to form a continuous dome under the inferior aspect of the piriform aperture.

CONCLUSION

Like the alar cartilages framing the tip of the nose, there are two continuous septolateral cartilages (SLCs) framing the mid-third of the nasal pyramid, likewise showing 2 cruras, medial and lateral, joined in a dome. The SLCs (also known as triangular cartilages) thus cannot be separated as 2 individual anatomic structures. These findings are in line with the shared embryological origin of all the elements composing the fibrocartilaginous nose in evo-devo theory.

The Relation Between the Lower Lateral Cartilages and the Function of the External Nasal Valve

INTRODUCTION

The position of the lower lateral cartilages (LLC) is closely related to the function of the external nasal valve (ENV). When there is a cephalic malposition of these cartilages, the nasal alae have inadequate support, which leads to ENV insufficiency during deep inspiration.

METHODS

Retrospective study with 60 patients evaluated: the positioning of the LLC and the occurrence of ENV insufficiency; the effectiveness of structuring the medial and lateral walls of the ENV; and the frequency of the grafts used for structuring it.

RESULTS

Of the 60 operated cases, 37 patients (62%) had ENV insufficiency, in 23 cases there was cephalic malposition of the LLC, and in the latter group 17 patients (74%) presented this insufficiency. A structured ENV was effective in the treatment of this insufficiency (p = 0.001). A lateral crural strut graft was performed in 24 cases (40%) of 60 patients operated. The alar contour graft was performed from 2013 to 2015 in 4 patients (22%) of 18 cases operated, and between 2016 and 2018 it was performed in 29 patients (69%) out of 42 cases. The columellar strut was routinely used from 2013 to mid-2016 in 33 cases (100%), and after that period until the present day the tongue-in-groove technique was performed in 11 cases (41%) and in the remaining 16 cases (59%) the caudal septal extension graft was performed.

CONCLUSION

Cephalic malposition of the LLC is an important red flag of ENV insufficiency. This insufficiency should be treated by structuring the walls of the ENV.

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 .

Sonography of the nasal cartilage: technique and normal anatomy

The cartilagineous parts of the nose may be involved in a wide range of pathologies ranging from trauma and infection to malignancy. If pathology is suspected on examination, an easy-to-use imaging modality would be helpful in everyday clinical work. Until now, sonography of the nasal cartilage has not been described. This short letter describes the technique and normal anatomy of the nasal cartilage on sonography. Sonography may evolve into a powerful imaging tool in imaging of the nasal cartilage.

Evaluation of human nasal cartilage nonlinear and rate dependent mechanical properties

Nasal reconstruction frequently requires donor cartilage and tissue, and ideally, donor tissue will closely emulate native nasal cartilage mechanics. Tissue engineering scaffolds, especially 3D printed scaffolds, have been proposed for nasal reconstruction, and the success of these constructs may depend on how well scaffolds reflect native nasal cartilage mechanical properties. Therefore, consistent and comprehensive characterization of native nasal cartilage mechanical properties is a foundation for nasal cartilage tissue engineering and reconstruction in general by providing design targets for reconstructive materials. Our group has previously shown the feasibility of producing scaffolds with porous architecture permitting chondrocyte growth and cartilage production. In this study, we determined the nonlinear and stress relaxation behavior of human nasal cartilage under unconfined compression. We then fit this experimental data to nonlinear elastic, nonlinear viscoelastic and nonlinear biphasic constitutive models. The resulting coefficients will provide design targets for nasal reconstruction and scaffold design as well as outcome measures for assessment of tissue engineered nasal cartilage.

Optimal harvest and efficient use of septal cartilage in rhinoplasty

BACKGROUND

Nasal septal cartilage is used to obtain favorable aesthetic and functional outcomes in rhinoplasty, but is often difficult to harvest or the harvested amount is insufficient. Therefore, the objective of this study is to introduce how to harvest septal cartilage optimally without losing and use harvested cartilage efficiently.

METHODS

From March 2015 to January 2020, we tried to harvest as much septal cartilage as possible while maintaining the L-strut in 30 patients. A spreader flap and septal rotation suture were used instead of a spreader graft. Also in patients who needed a spreader graft and septal extension graft, a spreader graft was used on one side and a one-piece spreader graft combined with a septal extension graft was performed on the other side. For tip plasty, a columella septal suture was performed first. Postoperative patient satisfaction was assessed using the Rhinoplasty Outcome Examination questionnaire.

RESULTS

No serious complications were observed. The patient satisfaction score was 50% or above in 27 patients (90%) and less than 50% in only three patients (10%). The average score was 81.5 points.

CONCLUSION

For septal cartilage deficiency, a spreader flap, the septal rotation suture, or onepiece spreader graft combined with a septal extension graft was used. The nasal tip was sufficiently rotated using the columellar septal suture technique first. These techniques made it possible to obtain good aesthetic outcomes using only septal cartilage, without harvesting other cartilage.

One-stage reconstruction of full-thickness alar defects with a folded nasolabial island flap

Background

The reconstruction of large full-thickness alar defects requires complex surgical procedures that are usually performed in two stages, with concomitant disadvantages in terms of patient trauma, surgical risk, and cost. This study presents a functional folded nasolabial island flap (FNIF) that can be used to repair large-sized full-thickness alar defects in a straightforward manner.

Methods

This retrospective study included seven patients who received a FNIF for a full-thickness alar defect between January 2007 and December 2020. The FNIF is different from the conventional nasolabial flap in that it is folded and twisted to achieve nostril reconstruction with a satisfactory three-dimensional mucosal lining in a single stage. The cosmetic and functional results of FNIF were evaluated by both patients and physicians.

Results

The age ranged from 51 to 82 years (mean, 65.6 years). The causes of the defects were squamous cell carcinoma, basal cell carcinoma, and trigeminal trophic syndrome. The nostril lining did not collapse, there was no hypertrophic scarring, and air movement through the nostrils on the flap side was normal. Overall, FNIF produced excellent aesthetic and functional outcomes, with minimal patient discomfort. There were no postoperative complications.

Conclusion

Compared with existing reconstruction methods for large full-thickness alar defects, FNIF can easily achieve aesthetic and functional success in a single-stage procedure. It provides satisfactory results for both the patient and the surgeon.

3D Bioprinting of Hyaline Cartilage Using Nasal Chondrocytes

Due to the limited self-repair capacity of the hyaline cartilage, the repair of cartilage remains an unsolved clinical problem. Tissue engineering strategy with 3D bioprinting technique has emerged a new insight by providing patient's personalized cartilage grafts using autologous cells for hyaline cartilage repair and regeneration. In this review, we first summarized the intrinsic property of hyaline cartilage in both maxillofacial and orthopedic regions to establish the requirement for 3D bioprinting cartilage tissue. We then reviewed the literature and provided opinion pieces on the selection of bioprinters, bioink materials, and cell sources. This review aims to identify the current challenges for hyaline cartilage bioprinting and the directions for future clinical development in bioprinted hyaline cartilage.

Age- and Gender-Related Variability in Nasal Tip Support

BACKGROUND

The age at which nasal tip support changes start to occur is unknown. Evaluation of nasal tip support is difficult, especially as the ideal nasal tip support pressure remains elusive. The aim of this study is to determine the nasal tip support pressure alterations relative to age and sex.

OBJECTIVES

The aim of this study is to determine the changers in resistance of the nasal tip support in relation to age and sex.

METHODS

This prospective clinical study was conducted between January and April 2019 at a tertiary health facility. Nasal tip resistances were measured in four different age-groups (20-29, 30-39, 40-64, and > 65 years) with a digital Newton meter. A total of 159 patients with a minimum of 36 patients per group were included in the study. Nasal tip resistance measurements were compared among nasal tip displacement distances of 2, 3, and 4 mm, focusing on age and sex.

RESULTS

The nasal tip resistance of the 20-29 age-group was significantly higher at 2, 3, and 4 mm nasal tip displacement distances, when compared with the 30-39 and 40-64 age-groups, whereas compared to the > 65 years group, it was significantly higher at 3 and 4 mm nasal tip displacement distances (p < 0.005). Nasal tip resistance of males was found to be significantly higher than that of females, at 3 and 4 mm nasal tip displacement distances (p < 0.001).

CONCLUSIONS

Nasal tip resistance is higher in males and universally decreases significantly after 30 years of age while remaining constant at later ages. Therefore, surgeons should prefer nasal tip resistance increasing techniques in the rhinoplasty operations that are performed on patients even from early years of age, in order to maintain and strengthen the nasal tip resistance.

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.

Fate and Development of Human Vomeronasal Organ - A Microscopic Fetal Study

INTRODUCTION

The existence of Vomeronasal organ in human is a controversial subject. Presence of Vomeronasal organ and its structure was not reported in standard text books. The presence of Vomeronasal organ in fetal life is doubtful. Hence identification of the organ by histological examination was planned.

MATERIALS AND METHODS

A study was conducted on resected specimens of nasal septum obtained from 45 spontaneously aborted fetuses from Obstetrics and Gynaecology department, PSG Institute of Medical Sciences and Research, Coimbatore, after ethical clearance.

RESULTS

The histological structure of Vomeronasal organ was observed from 11 weeks old fetus. The epithelial lining of the organ, presence of cilia, presence of lamina propria, acini and the blood vessel and the types of cells were observed. The organ was lined by pseudostratified columnar epithelium. The organ showed Lamina propria with serous acini from 18 weeks fetus. Vomeronasal duct opening into the nasal cavity and three types of cells were observed in 28 weeks fetus.

CONCLUSION

Knowledge about the persistence of Vomeronasal organ in fetuses and its structure need to be known. The organ may be found as a putative pit posterior to anterior nasal spine. The organ may be damaged in nasal septal surgeries and nasal endoscopic procedures. The organ may not be seen on gross examination in all human fetuses and cadavers.

Secondary rhinoplasty for unilateral cleft lip nasal deformity using the complex of autologous costal cartilage and fascia grafts

BACKGROUND

Secondary unilateral cleft lip nasal deformity is a prevalent condition in the world, and surgical repair remains a formidable challenge. The objective of the study is to investigate functionally and aesthetically outcomes of a new technique using a complex of autologous costal cartilage and fascia grafts to repair the secondary unilateral cleft lip nasal deformity.

METHODS

First, the autologous costal cartilage and fascia were harvested from a total of 34 patients with secondary unilateral cleft lip nasal deformity, who were undergoing treatments at the First Affiliated Hospital of Xi'an Jiaotong University from April 2020 to June 2023. Then, the cartilage was sub-divided into 6 pieces and placed on the depressed alar base, nasal columella, lower lateral cartilage, and nasal tip. At the same time, the fascia was trimmed to cover the nasal tip cap graft and augment the dorsum of the nose. Patient outcomes were assessed through subjective evaluation and objective anthropometric measurements. In addition, associated complications were also examined.

RESULTS

All were primary healing incisions, and no patients were encountered with any clinical complications. We found that the overall mean score of the Independent Rhinoplasty Outcome Score (IROS) was very good during the subjective assessment. Also, the objective measurements indicated an excellent nasal symmetry. Furthermore, both functionally and aesthetically satisfactory outcomes were obtained in all the patients during long-time follow-up.

CONCLUSIONS

Secondary rhinoplasty using the complex of autologous costal cartilage and fascia grafts is a safe and effective approach for unilateral cleft lip nasal deformity repair.

Correction of Short Nose Using M-shaped Cartilage in Asian Patients: Finite Element Analysis and Recommendations for Surgery

BACKGROUND

Using M-shaped cartilage grafts is a new method for the correction of short nose deformity with good effect for Asians. Although the basic approach to M-shaped cartilage surgery is well understood, there is a great deal of uncertainty when plastic surgeons perform the procedure, and still a lack of standard guidance on the specific details.

METHODS

In this study, the authors used finite element analysis to explore and compare postoperative cartilage stability of different fixing methods, different suturing positions, and different sizes of M-shaped cartilage. The authors applied a 0.01 N load to a 1 cm2 area of the nasal tip to simulate nasal tip palpation and compared the maximum deformations of different groups, which were used to make stability judgments.

RESULTS

The maximum deformation of the model was the least when the M-shaped cartilage was fixed medially to the septal cartilage and laterally to the outer crura of the lower lateral cartilage. At the same time, the maximum deformation was the least when the M-shaped cartilage was sutured to the middle of the nasal septal cartilage. Besides, the length of M-shaped cartilage was preferably around 30 mm, while its width was not worthy of being overly concerned.

CONCLUSIONS

For optimal postoperative stability of Asian short nose correction, the M-shaped cartilage should be sutured and fixed medially to the middle of the septal cartilage and laterally to the lateral crura of the lower lateral cartilage, and the length of the M-shaped cartilage should be controlled at around 30 mm.

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 .

The Effect of Crosslinking Density on Nasal Chondrocytes' Redifferentiation

Hydrogels appear to be an attractive class of biomaterial for cartilage tissue engineering due to their high water content, excellent biocompatibility, tunable stiffness, etc. The crosslinking density of the hydrogel can affect their viscoelastic property, and therefore potentially impact the chondrogenic phenotype of re-differentiated chondrocytes in a 3D microenvironment through physical cues. To understand the effect of crosslinking densities on chondrocytes phenotype and cellular interaction with the hydrogel, this study utilized a clinical grade thiolate hyaluronic acid and thiolate gelatin (HA-Gel) hydrogel, crosslinked with poly(ethylene glycol) diacrylate to create various crosslinking densities. The HA-Gel hydrogels were then mixed with human nasal chondrocytes to generate neocartilage in vitro. The influence of the hydrogel crosslinking density and the viscoelastic property on the cell behaviours on the gene and matrix levels were evaluated using biochemistry assays, histology, quantitative polymerase chain reaction (qPCR) and next-generation sequencing (RNA seq). In general, the differences in the storage modulus of the HA-Gel hydrogel are not enough to alter the cartilaginous gene expression of chondrocytes. However, a positively correlated trend of PPAR-γ gene expression to the crosslinking density was measured by qPCR. The RNA-seq results have shown that 178 genes are significantly negatively correlated and 225 genes are positively correlated to the crosslinking density, which is worth investigating in the future studies.

Aesthetic and Functional Consequences of Spreader Graft without Suturing To the Upper Lateral Nasal Cartilage: A Randomized Double-Blinded Clinical Trial

Background

Considering the importance of the spreader graft technique in order to prevent collapse and airway retention and the importance of its effect on the dorsal aesthetic line and nasal width, in this study we compared the outcome of suturing spreader graft to septum _upper lateral cartilageas the classic technique to suturing spreader graft only to septum.

Methods

This comparative observational study was conducted on 50 consecutive patients referred to Rhinoplasty Department in 15 khordad Hospital from 2019 - 2020 . The study participants were randomly assigned into two groups which scheduling the new spreader graft technique without suturing the upper lateral cartilage (n = 25) or the frequent spreader graft technique with suturing to both septum and upper lateral nasal cartilage (n = 25). The nasal obstruction degree, the status and health-related quality of life, patients' satisfaction, and subjective mental image of the nasal structure were the study endpoint. The patients were followed-up for six months.

Results

The two groups were matched for gender and age. Although all study endpoints significantly improved in both groups, but the six-month trend of the change in each parameter was different in the two groups with superior improvement in those who planned for spreader graft technique without suturing the upper lateral cartilage.

Conclusion

In patients scheduling for selective rhinoplasty, new procedural technique including spreader graft without suturing to upper lateral cartilage can lead to more postoperative favorable outcome with regard to patients' satisfaction of the procedure, lack of obstructive symptoms, aesthetic feature, and health-related quality of life as compared to suturing to both septum and upper lateral cartilage.

M-Shaped Auricular Cartilage Grafts for Correcting Short Nose Deformity in Asians: A Retrospective Study

BACKGROUND

The demand for rhinoplasty in Asia is growing annually, and short nose deformity has been one of the main reasons for the surgery due to its high incidence. There is an urgent need for rhinoplasty suitable for Asians because of their different facial features from Westerners. The M-shaped auricular cartilage rhinoplasty has been developed as a new method for correcting short nose deformity for Asians. This study aimed to evaluate the aesthetic and functional results of M-shaped auricular cartilage rhinoplasty compared to clinically commonly used rhinoplasty methods.

METHODS

A total of 45 patients were enrolled and divided into three groups of 15 patients: The first group underwent M-shaped auricular cartilage rhinoplasty, the second group underwent auricular-septal cartilage rhinoplasty, and the third group underwent overlapped auricular cartilage rhinoplasty. All of these patients underwent comprehensive rhinoplasty and had silicone or expanded polytetrafluoroethylene implants in the dorsum of their noses.

RESULTS

The patient score improvements on the three patient-reported outcome measures were higher in the M-shaped auricular cartilage rhinoplasty group (1.65/1.79/0.11) compared with the overlapped auricular cartilage rhinoplasty group (1.40/1.51/0.05), and the score improvements in the auricular-septal cartilage rhinoplasty group (2.04/1.98/0.28) were the highest.

CONCLUSIONS

This is a retrospective clinical study demonstrating the clinical efficacy of M-shaped auricular cartilage rhinoplasty. Compared with the overlapped auricular cartilage rhinoplasty, the effect of this novel M-shaped method is better. However, when compared to the auricular-septal cartilage rhinoplasty with septal extension and reinforcement using nasal septal cartilage, its effect is slightly worse.

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 .