Radiotherapy and Facial nerve graft

Facial nerve function after raadiotherapy
effect of high-dose radiation therapy on facial nerve grafts is controversial.
Some believe radiotherapy is so detrimental to the outcome of facial nerve
graft function that dynamic or static slings should be performed instead of
facial nerve grafts in all patients who are to receive postoperative radiation
o Problem- the facial function achieved with dynamic and static slings is
almost always inferior to that after facial nerve grafts.
Lit review
 Brandt et al J Reconstr Microsurg. 1999 Aug;15(6):421-5. (MD Anderson)
o Rat study
o Group 1 animals served as controls and Groups 2 and 3 received
fractionated postoperative irradiation doses of 66 and 106 Gy,
o no significant difference in the nerve-fiber density of the grafted or
distal segments, compared to controls.
o Functional evaluation by walking-track analysis showed no difference
between the irradiated groups and controls over the length of the study.
o These results suggest that acute nerve grafting of nerve defects in the
face of planned postoperative irradiation is safe.
 Brown et al Int J Radiat Oncol Biol Phys. 2000 Oct 1;48(3):737-43. (Mayo
o 66 patients with nerve grafts following parotidectomy
o Negative prognostic factors for achieving a functional facial nerve:
1. presence of preoperative facial nerve palsy
2. duration of preoperative palsy
3. age greater than 60 years
o Radiotherapy was not a negative prognostic factor. Comparing
irradiated and unirradiated grafts revealed no difference in best facial
nerve function achieved
 Reddy Laryngoscope 1999 Jun;109(6):894-9.
o Postoperative radiotherapy did not appear to affect return of function,
and younger patients consistently achieved good functional outcomes
after nerve grafting
o Older patients frequently require surgical procedures for eye