Challenges in Nasal Cartilage Tissue Engineering to Restore the Shape and Function of the Nose.

The repair of nasal septal cartilage is a key challenge in cosmetic and functional surgery of the nose, as it determines its shape and its respiratory function. Supporting the dorsum of the nose is essential for both the prevention of nasal obstruction and the restoration of the nose structure. Most surgical procedures to repair or modify the nasal septum focus on restoring the external aspect of the nose by placing a graft under the skin, without considering respiratory concerns. Tissue engineering offers a more satisfactory approach, in which both the structural and biological roles of the nose are restored. To achieve this goal, nasal cartilage engineering research has led to the development of scaffolds capable of accommodating cartilaginous extracellular matrix-producing cells, possessing mechanical properties close to those of the nasal septum, and retaining their structure after implantation in vivo. The combination of a non-resorbable core structure with suitable mechanical properties and a biocompatible hydrogel loaded with autologous chondrocytes or mesenchymal stem cells is a promising strategy. However, the stability and immunotolerance of these implants are crucial parameters to be monitored over the long term after in vivo implantation, to definitively assess the success of nasal cartilage tissue engineering. Here, we review the tissue engineering methods to repair nasal cartilage, focusing on the type and mechanical characteristics of the biomaterials; cell and implantation strategy; and the outcome with regard to cartilage repair.

Objective diagnosis of internal nasal valve collapse by four-phase rhinomanometry.

Background: Internal valve collapse is a frequent cause of nasal obstruction but remains poorly understood and is sometimes treated inappropriately as a result. No functional or imaging test for the condition has been validated and the reference diagnostic technique is physical examination. The objective of this study was to evaluate the potential of four-phase rhinomanometry as a diagnostic test for internal valve collapse. Methods: In a case-control diagnostic accuracy study, the nostrils of adult patients consulting for chronic nasal obstruction were classified as "collapsed" or "non-collapsed" based on clinical findings. Four-phase rhinomanometry was performed in all patients. The area defined by the path of the flow/pressure curve in the two phases of inspiration (the "inspiratory loop area" or "hysteresis loop area") was calculated for both nasal cavities and the threshold value with the highest Youden index was identified. Results: Sixty-six patients (132 nostrils) were included with 72 nostrils classified as collapsed and 60 as non-collapsed. Before nasal decongestion, the inspiratory loop area with the highest Youden index was 17.3 Pa L s-1 and the corresponding sensitivity and specificity were 88.3% (95% confidence interval, 80.0-95.0%) and 89.9% (82.6-95.7%), respectively. Conclusions: In these patients, a cutoff inspiratory loop area in four-phase rhinomanometry data reproduced clinical diagnoses of internal valve collapse with high sensitivity and specificity. This method may offer a firmer basis for treatment indications than subjective physical examinations. Level of evidence: Level 4.

Combination of bioactive factors and IEIK13 self-assembling peptide hydrogel promotes cartilage matrix production by human nasal chondrocytes.

Nasal reconstruction remains a challenge for every reconstructive surgeon. Alloplastic implants are proposed to repair nasal cartilaginous defects but they are often associated with high rates of extrusion and infection and poor biocompatibility. In this context, a porous polymeric scaffold filled with an autologous cartilage gel would be advantageous. In this study, we evaluated the capacity of IEIK13 self-assembling peptide (SAP) to serve as support to form such cartilage gel. Human nasal chondrocytes (HNC) were first amplified with FGF-2 and insulin, and then redifferentiated in IEIK13 with BMP-2, insulin, and T3 (BIT). Our results demonstrate that IEIK13 fosters HNC growth and survival. HNC phenotype was assessed by RT-PCR analysis and neo-synthesized extracellular matrix was characterized by western blotting and immunohistochemistry analysis. BIT-treated cells embedded in IEIK13 displayed round morphology and expressed cartilage-specific markers such as type II and type IX collagens and aggrecan. In addition, we did not detect significant production of type I and type X collagens and gene products of dedifferentiated and hypertrophic chondrocytes that are unwanted in hyaline cartilage. The whole of these results indicates that the SAP IEIK13 represents a suitable support for hydrogel-based tissue engineering of nasal cartilage. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 893-903, 2019.

A comparative retrospective study: hypoglossofacial versus masseterofacial nerve anastomosis using Sunnybrook facial grading system.

INTRODUCTION: The aim of our study is to compare the functional results between two surgical techniques for reanimation of facial paralysis: hypoglossal-to-facial versus masseteric-to-facial nerve anastomosis. METHODS: This is a retrospective study of 13 patients treated for complete facial paralysis in two medical tertiary centers. The patients were classified into two groups. First group: masseteric-to-facial nerve anastomosis. Second group: hypoglossofacial nerve anastomosis. Sunnybrook facial grading system was used to evaluate the functional results. The mean scores were compared using Mann-Whitney test. The correlation between the age at surgery, the delay in time from the onset of the facial paralysis to the time of surgery and the results of Sunnybrook scores was studied using correlation and linear regression. RESULTS: No significant statistical difference was found between the mean of total score of the two groups (first group = 38 ± 4.898, second group = 37.83 ± 4.956). All the patients treated by hypoglossofacial nerve anastomosis presented with hemiglossal atrophy. We found slight superiority for the masseterofacial nerve anastomosis in dynamic movements, whereas at rest the hypoglossofacial anastomosis is slightly better. All the differences were not statistically significant. No correlation was found between the age at surgery (age range included 32-73 years) and post-operative results. No correlation was found between the delays up to 24 months from the onset of the facial paralysis and post-operative results. CONCLUSION: Our study showed that both types of anastomosis are effective with comparable results. The masseterofacial nerve anastomosis is preferred when possible to avoid the hemiglossal atrophy and its complications.

Safeguarding Fertility With Whole Ovary Cryopreservation and Microvascular Transplantation: Higher Follicular Survival With Vitrification Than With Slow Freezing in a Ewe Model.

BACKGROUND: In young women, ovarian cortex cryopreservation before gonadotoxic chemotherapy and its avascular grafting after cancer healing permitted fertility restoration. However, ischemia reduced the grafts' lifespan. Microvascular transplantation of cryopreserved whole ovary may allow immediate revascularization, ensuring better fertility preservation, but the best cryopreservation method is unknown. We aimed to compare slow freezing and vitrification of whole ovary for fertility preservation purposes, in an ewe model. METHODS: Twelve ewes were allocated at random to slow freezing (n = 6) or vitrification group (n = 6). Ewes' left ovary was removed and cryopreserved. Dimethyl sulfoxide 2 M was used as cryoprotector for slow freezing. Vitrification was obtained using increasing concentrations of a vitrification solution of the latest generation (VM3) and gradual temperature lowering to minimize toxicity. After a month, the right ovary was removed, the left ovary was thawed/warmed, and its vessels were anastomosed to the right pedicle. Fertility and ovarian function were assessed for 3 years. Ovarian follicles in native and transplanted ovaries were counted and compared at study completion. RESULTS: Hormonal secretion resumed in all ewes of both groups. One ewe of the slow-freezing group delivered healthy twins 1 year 9 months and 12 days after transplantation. Estimated whole follicle survival was very low in both groups but significantly higher after vitrification than after slow freezing (0.3% ± 0.5% vs 0.017% ± 0.019%, respectively; p < 0.05). CONCLUSIONS: Further progress is needed before whole-ovary cryopreservation can be considered an option for safeguarding fertility. Whole ovary vitrification provides better follicular survival compared to slow freezing and may be a valuable cryopreservation option.

Infraorbital and infratrochlear nerve blocks combined with general anaesthesia for outpatient rhinoseptoplasty: A prospective randomised, double-blind, placebo-controlled study.

INTRODUCTION: We conducted a study to determine the efficacy of bilateral extraoral infraorbital and infratrochlear nerve blocks during outpatient rhinoseptoplasty under general anaesthesia. PATIENTS AND METHODS: In this prospective, double-blind, randomised, controlled trial, 40 adult patients undergoing outpatient rhinoseptoplasty under general anaesthesia were assigned to receive bilateral infraorbital and infratrochlear nerve blocks with either 10mL of 0.25% levobupivacaine (Group LB) or isotonic saline (control group). Patients in Group LB received 0.1mL/kg of isotonic saline as a placebo and patients in the control group received 0.1mL/kg of morphine. The primary endpoint was total perioperative morphine consumption (intraoperative and in the post-anaesthesia care unit). The secondary endpoints were pain scores, time spent in the post-anaesthesia care unit and the outpatient ward, block-related complications and patient satisfaction. RESULTS: The total dose of perioperative morphine was lower in Group LB than in the control group (2.5±2.8mg versus 9.5±3.5mg, respectively, P<0.001). The mean±SD or median [IQR] times spent in the post-anaesthesia care unit (60±10min and 78±33min, respectively, P<0.03) and in the outpatient ward (210 [178-223] min versus 275 [250-300] min, respectively, P<0.001) were lower in Group LB than in the control group. There were no differences between groups for other endpoints. CONCLUSION: Bilateral extraoral infraorbital and infratrochlear nerve blocks performed with 0.25% levobupivacaine during general anaesthesia combining remifentanil and desflurane reduce the perioperative dose of morphine and the time spent in the post-anaesthesia care unit and the outpatient ward in adult patients undergoing outpatient rhinoseptoplasty.