【Method】The facial nerve trunk of 8-week-old Lewis rats was ligated and detached to prepare a facial nerve complete paralysis model. The affected side marginal mandibular branch was sutured end to side hypoglossal nerve. And Cross-nerve graft from healthy-side was transferred to affected side. 5 weeks later, Cross-nerve graft was sutured marginal mandibular branch end to end (Baby-sitter group). After 13 weeks from the first operation, physiological function evaluation was performed using retrograde tracer, induced electromyogram (CMAP), and mimic muscle and facial nerve branch were collected, and a histologic comparison study with intact group and non treatment group was conducted went.
【Result】 The staining of facial nucleus by retrograde tracer proved re-innervation of affected facial muscle by babysitter method. In CMAP, Babysitter group was also significantly higher than Amplitude, Duration, and Latency compared to non - treatment group. In the histological examination, the number of myelinated fibers, axon diameter and myelin sheath thickness were significantly higher in the Intact group than in the Baby-sitter group.
【Discussion】 In this study, the “baby-sitter” procedure for rat facial nerve palsy was established. Compared to the non-treated group histologically and physiologically, the Baby-sitter group could confirm the effect of shortening the denervation period using the affected hypoglossal nerve prevention effect of mimic muscle atrophy.