Facial Nerve Repair by Muscle-Vein Conduit in Rats: Functional Recovery and Muscle Reinnervation.

Area of Science:

• Neurosurgery
• Regenerative Medicine
• Animal Models

Background:

• Facial nerve injuries are common in head and neck trauma, often leading to incomplete functional recovery.
• Postparalytic syndrome, including synkinesia and altered blink reflexes, frequently occurs after nerve repair.
• Current microsurgical techniques for nerve repair have limitations in restoring full function.

Purpose of the Study:

• To evaluate the efficacy of a novel nerve-gap repair strategy using an autologous vein filled with skeletal muscle.
• To assess the impact of this muscle-vein-combined conduit (MVCC) on axonal regeneration and neuromuscular junction reinnervation.
• To determine if MVCC improves the recovery of whisking function in a rat model of facial nerve injury.

Main Methods:

• Transection and suture of the buccal branch of the facial nerve in rats.
• Repair of the nerve gap using an autologous vein graft filled with denervated skeletal muscle (MVCC).
• Assessment of vibrissal (whisking) motor performance via video motion analysis.
• Immunofluorescence imaging to analyze target muscle reinnervation and neuromuscular junction characteristics.

Main Results:

• The muscle-vein-combined conduit (MVCC) demonstrated a positive effect on improving whisking function after facial nerve repair.
• Evidence suggests improved axonal regeneration and reduced polyinnervation at neuromuscular junctions.
• Enhanced coordinated function of facial muscles was observed in rats treated with MVCC.

Conclusions:

• Autologous vein grafts combined with skeletal muscle show promise for enhancing facial nerve repair outcomes.
• This approach may promote a higher degree of monoinnervation and improve functional recovery after nerve injury.
• The findings support the use of trophic sources within vascular grafts for nerve regeneration.