Chapter 64 - Facial Reanimation

Question 1

How soon does facial reinnervation need to take place

Answer 1

by 12-18mo post injury

nerve and motor endplate fibrosis

Question 2

Tool to use to tell if spontaneous recovery occuring

Answer 2

EMG

Question 3

Synkinesis

Answer 3

hyperkinetic uncoordinated mass facial movement
aberrent regeneration
May present as increased lacrimation
Tx botox

Question 4

How to easily distinguish between HB 3, 4, 5

Answer 4

3: noticeable weakness, complete eye closure requiring maximum effort
4: incomplete eye closure
5: asymmetry at rest

Question 5

How EMG works

Answer 5

study depolarization of mm fiber
Denervated: spontaneous fibrillation potentials
Regen: polyphasic action potentials
Normal: no electrical activity at rest

Question 6

potential sequelae of lagophthalmos

Answer 6

dry eye, exposure keratitis, corneal ulceration, blindness

Question 7

Ways to dynamically reanimate face

Answer 7

cable graft, cross-facial n graft, XII to VII, V to VII

gracilis flap, transposition of temporalis or masseter, temporalis tendon transfer

Question 8

how to treat lower lid with CN VII paralysis

Answer 8

snap test to determine laxity
medial laxity –> tx with medial canthoplasty to prevent eversion of inferior punctum and epiphora
lateral laxity –> tx with horizontal lid shortening of producing scleral show or ectropion

Question 9

Upper lip tx with CN VII paralysis

Answer 9

gold or platinum weight (low reactivity, high density)

Can give you undesirable lid closing when supine

Question 10

How soon should you repair a transected facial nerve?

Answer 10

Within 72 hours (when wallerian degeneration occurs)

Must reapproximate primarily without tension (may need to mobilize or re-route adjacent segments)

Question 11

What should you do if you can’t reapproximate CN VII primarily without tension?

Answer 11

interposition nerve graft (auricular or sural)

Question 12

Cross-facial nerve graft

Answer 12

graft sural nerve onto functioning side buccal and zygomatic branches
9-12mo later, do neurorraphies between paralyzed nerve branches and the cross-face graft…requires functional motor end plates on paralyzed side

Question 13

What is nerve transposition

Answer 13

coap facial n to another CN
Use when distal branches viable, but no viable proximal facial stump
XII, V

Question 14

When to use muscle transposition

Answer 14

If nerve graft not possible
temporalis tendon over lateral commissure or melolabial fold.
temporalis muscle transfer has cosmetic deformity associated

Question 15

free flap facial reanimation

Answer 15

cross-facial nerve graft
Wait 9-12 mo
gracilis transfer, connect anterior br of obturator nerve to cross graft, and adductor br of deep femoral plus venae comitantes to facial a/v

Question 16

Static facial procedures used for CN VII paralysis

Answer 16

for asymmetry of brow

May also do sling procedures to correct midface, melolabial fold, nasal obstruction