Facial Nerve Regeneration Through Semipermeable Porous Chambers

Abstract

Peripheral nerve regeneration, over a 10-mm transectional gap, was determined in 70 rabbit buccal divisions of the facial nerve using two entubational systems (semipermeable porous and impermeable silicone chambers) and three naturally occurring media (serum, blood, saline) during a 5-week period. The number of myelinated axonal regenerates at the midchamber and 2 mm into the distal transected neural stump were counted in each group and compared to normative pooled myelinated axonal counts in nine normal rabbit buccal divisions of the facial nerve. Semipermeable porous chambers had an overall greater regeneration success rate (75% vs. 42.8%) and regained, on average, a higher number of myelinated axons (51.4% vs. 26.1%) than silicone chamber regenerates. Semipermeable porous chambers containing serum or blood had significantly higher regeneration success, myelinated axonal couts, and percentages of neural innervation of the distal transected neural stump. Both entubational systems produced similar axonal counts with intraluminal saline. The highest overall success rate (93.7%) and average number of myelinated axons per chamber (3072) were achieved in porous chambers filled with serum.