[Reconstruction of nasal cartilage defects using a tissue engineering technique based on combination of high-density polyethylene and hydrogel]. / Reconstruction du cartilage nasal par ingénierie tissulaire à base de polyéthylène de haute densité et d'un hydrogel.

AIM OF THE STUDY: Nasal reconstruction remains a challenge for any surgeon. The surgical indications for nasal reconstruction after oncologic resection, trauma or as part of cosmetic rhinoplasty, are steadily increasing. The current attitude for reconstruction is the use of autologous cartilage grafts of various origins (septal, ear or rib) trying to restore a physiological anatomy but their quantity is limited. Thus, in order to produce an implantable cartilaginous model, we developed a study protocol involving human nasal chondrocytes, growth factors and a composite biomaterial and studied at the molecular, cellular and tissue level the phenotype of the chondrocytes cultured in this model. MATERIALS AND METHODS: After extraction of chondrocytes and their amplification on plastic, the cells were cultured for 15 days either in monolayer or within an agarose hydrogel or a composite biomaterial (agarose/high density polyethylene: Medpor(®)) in the presence or not of a cocktail of soluble factors (BIT): bone morphogenetic protein-2 (BMP-2), insulin and triiodothyronine (T3). The quality of the chondrocyte phenotype was analyzed by PCR, western blotting and immunohistochemistry. RESULTS: During their amplification in monolayer, chondrocytes dedifferentiate. However, our results show that the BIT cocktail induces redifferentiation of chondrocytes cultured in agarose/Medpor with synthesis of mature chondrogenic markers. Thereby, chondrocytes associated with the agarose hydrogel will colonize Medpor and synthesize an extracellular matrix characteristic of nasal cartilage. CONCLUSION: This nasal cartilage tissue engineering protocol provides the first interesting results for nasal reconstruction.

[Importance of a molding nasolabial flap in the reconstruction of mobile nose defects, a review of 25 cases]. / Intérêt du lambeau nasogénien (LNG) modelant dans la reconstruction des pertes de substances du nez mobile à propos de 25 cas.

INTRODUCTION: Mobile nose reconstruction, because of its location, its anatomy and its functional role is a surgical challenge. We describe throughout this article the surgical technique and the importance of the nasolabial flap in a single-step procedure for repairing mobile nose defects. MATERIALS AND METHODS: We present 25 cases of mobile nose defects secondary to an oncologic etiology, affecting the supratip, the alar margin and the columella. Patients benefited from a superiorly pedicled molding nasolabial flap harvested in a one-step procedure under local anesthesia. RESULT: Aesthetic result of each repair was evaluated according to 5 criteria and was considered as very satisfactory by the surgeons. No complication such as necrosis or infection was recorded. DISCUSSION: A molding nasolabial flap allows optimum repair of the mobile nose. It represents reliability, elasticity at the price of minimal scarring. We find it an important tool in the therapeutic armamentarium in patients with tissue loss in mobile nose.

[Analysis of the projection of the nasal tip]. / Analyse de la projection de la pointe nasale.

The success of a rhinoplasty is conditioned by a detailed preoperative analysis of the morphology of the nose and face of the patient. A good knowledge of the characteristic reference marks and nasal proportions authorize a detailed description of the nose. The position of the nasal tip is one of the principal characteristics of the nose. It is expressed by the combination of its projection and its height. A reflexion on the position of the tip and its ideal position post-operatively enabled us to work out a conceptual approach aiming at guiding the surgical project. The drawing of two circles centered on the nasal pyramid is the expression of this concept. Thus, a detailed analysis of the nasal pyramid and a biomechanical approach are the key to a relevant surgical plan.