Syngeneic Transplantation of Rat Olfactory Stem Cells in a Vein Conduit Improves Facial Movements and Reduces Synkinesis after Facial Nerve Injury.

BACKGROUND: Posttraumatic facial paralysis is a disabling condition. Current surgical management by faciofacial nerve suture provides limited recovery. To improve the outcome, the authors evaluated an add-on strategy based on a syngeneic transplantation of nasal olfactory stem cells in a rat model of facial nerve injury. The main readouts of the study were the recording of whisking function and buccal synkinesis. METHODS: Sixty rats were allocated to three groups. Animals with a 2-mm facial nerve loss were repaired with a femoral vein, filled or not with olfactory stem cells. These two groups were compared to similarly injured rats but with a faciofacial nerve suture. Olfactory stem cells were purified from rat olfactory mucosa. Three months after surgery, facial motor performance was evaluated using video-based motion analysis and electromyography. Synkinesis was assessed by electromyography, using measure of buccal involuntary movements during blink reflex, and double retrograde labeling of regenerating motoneurons. RESULTS: The authors' study reveals that olfactory stem cell transplantation induces functional recovery in comparison to nontransplanted and faciofacial nerve suture groups. They significantly increase (1) maximal amplitude of vibrissae protraction and retraction cycles and (2) angular velocity during protraction of vibrissae. They also reduce buccal synkinesis, according to the two techniques used. However, olfactory stem cell transplantation did not improve axonal regrowth of the facial nerve, 3 months after surgery. CONCLUSIONS: The authors show here that the adjuvant strategy of syngeneic transplantation of olfactory stem cells improves functional recovery. These promising results open the way for a phase I clinical trial based on the autologous engraftment of olfactory stem cells in patients with a facial nerve paralysis.

Lower lateral crural turnover flap combined with alar batten graft for the long-term result of the treatment of alar convexities.

INTRODUCTION: Concave lower lateral cartilages not only cause an esthetic defect but can also lead to external nasal valve insufficiency. The objective of this article is to analyze the combination of two well-known surgical techniques: turning over the alar cartilages as well as the addition of grafts in order to obtain satisfying esthetic and functional long term results. MATERIALS AND METHODS: From August 2016 to July 2018, 62 rhinoplasties, a combination of both primary and revision cases, were performed at the Rouen University Hospital in France. Six of these involved the correction of concave alar cartilages. The turnover technique alone or in combination with Batten grafts was performed. RESULTS: Immediate and 3-months post-operative esthetic results using the turnover flap technique were satisfactory. Alar batten grafts were occasionally employed in order to maintain the newly positioned alar cartilages and avoid long-term contour depressions. CONCLUSION: The combination of these two techniques seems to be an interesting solution to maintain long-term esthetic results.