1. بسم الله الرحمن الرحيم

2. THE FACIAL NERVE

3. FACIAL NERVE FIBERS Motor Secreto-motor Taste Sensory
to the stapedius and facial muscles
Secreto-motor
to the submandibular, sublingual salivary glands and to the lacrimal glands
Taste
from the anterior two thirds of tongue and palate
Sensory
from the external auditory meatus

4. ANATOMICAL DIVISIONS Intracranial Cranial (intratemporal)
Nuclei & cerebellopontine
Cranial (intratemporal)
Meatal
Fallopian canal ( labyrinthine, tympanic and mastoid )
Extracranial (extratemporal)

5. THE INTRACRANIAL PART
1. The nucleui

6. Upper motor lesions spare the upper facial muscles and affect the contralateral lower face
Lower motor lesions affect all the ipsilateral facial muscles

7. UPPER MOTOR
LOWER MOTOR

8. Intracranial part (CP angle)

9. THE INTRA-TEMPORAL (CRANIAL)

11. THE EXTRACRANIAL PART

13. THE EXTRACRANIAL PART

14. FACIAL NERVE FIBERS Motor Secreto-motor Taste Sensory
to stapedius, and facial muscles
Secreto-motor
to the submandibular, sublingual, and lacrimal glands
Taste
from the anterior two thirds of tongue and palate
Sensory
from the external auditory meatus

15. Distribution of facial nerve fibers

16. The secreto-motor and the taste fibres

17. VARIATIONS AND ANOMALIES

19. CLINICAL MANIFESTATIONS
Paralysis of facial muscles
Asymmetry of the face

26. CLINICAL MANIFESTATIONS
Paralysis of facial muscles
Asymmetry of the face
Inability to close the eye
Accumulation of food in the cheek
Phonophobia
Dryness of the eyes
Loss of taste

27. PATHOPHYSIOLOGY OF FACIAL NERVE INJURY

28. Neuropraxia (Conduction block)
Neurotmeses (Degeneration)

30. REGENERATION

31. Neuropraxia (Conduction block)
Neurotmeses (Degeneration)

33. Electrophysiological Tests
Detect degeneration of the nerve fibers
Useful only hours following the onset of the paralysis

34. Electrophysiological Tests
Nerve Excitability Test (NET)
Electroneurography (ENoG)

35. Nerve excitability test (NET)
The current’s thresholds required to elicit just-visible muscle contraction on the normal side of the face are compared with those values required over corresponding sites on the side of the paralysis

36. Electroneurography (ENoG)
The amplitude of action potentials in the muscles induced by the maximum current is compared with the normal side ; and used to calculate the percentage of intact axons.

38. Indications of Electrophysiological Tests
In clinically complete facial paralysis to differentiate between conduction block (neuropraxia) and degeneration of nerve fibers (neurotmeses)

39. Interpretation of the tests
Not useful in the first 48 – 72 hours
After hours (the time required for degeneration to take place)
Normal results means that there is no degeneration (Neuropraxia)
Abnormal results means degeneration

40. TOPOGNOSTIC TESTS
Indicated in some cases to locate the site of the injury

41. TOPOGNOSTIC TESTS
Schirmer's test
Test the lacrimation function

42. TOPOGNOSTIC TESTS
Schirmer's test
Stapedial reflex
Taste sensation

43. TOPOGNOSTIC TESTS Schirmer's test Stapedial reflex Taste sensation
Salivary flow

44. CAUSES OF FACIAL PARALYSIS
Congenital: Birth trauma
Traumatic: Head and neck injuries & surgery
Inflammatory: O.M, Necrotizing O.E., Herpes
Neoplastic: Meningioma, malignancy ear or parotid
Neurological: Guillain-Barre syndrome, multiple sclerosis
Idiopathic: Bell’s palsy

45. CAUSES OF FACIAL PARALYSIS
Intracranial causes
Cranial (intratemporal) causes
Extracranial causes

46. Congenital Facial Palsy
80-90% are associated with birth trauma
% are associated with developmental lesions

47. INFLAMMATORY CAUSES OF FACIAL PARALYSIS

48. Facial Paralysis in AOM
Mostly due to pressure on a dehiscent nerve by inflammatory products
Usually is partial and sudden in onset
Treatment is by antibiotics and myringotomy

49. Facial Paralysis in CSOM
Usually is due to pressure by cholesteatoma or granulation tissue
Insidious in onset
May be partial or complete
Treatment is by immediate surgical exploration and “proceed”

50. HERPES ZOSTER OTICUS (RAMSAY HUNT SYNDROME)
Herpes zoster affection of cranial nerves VII, VIII, and cervical nerves
Facial palsy, pain, skin rash, SNHL and vertigo

52. HERPES ZOSTER OTICUS (RAMSAY HUNT SYNDROME)
Herpes zoster affection of cranial nerves VII, VIII, and other nerves
Facial palsy, pain, skin rash, SNHL and vertigo
Vertigo improves due to compensation
SNHL is usually irreversible
Facial nerve recovers in about 60%
Treatment by: Acyclovir, steroid and symptomatic

53. Traumatic Facial Injury
Iatrogenic
Temporal bone fracture

54. Iatrogenic Facial Nerve Injury
Operations at the CP angle, ear and the parotid glands

55. Temporal Bone Fracture
Longitudinal
Transverse

56. Transverse Fracture

57. Pathology
Edema
Transection of the nerve

58. Management of Traumatic Facial Nerve Injury
If it is delayed in onset, it is usually incomplete and is due to edema
Conservative
If of immediate onset, it is usually complete and due to transection of the nerve
Surgical repair

59. SURGICAL REPAIR

60. DIRECT ANASTOMOSIS

61. NERVE GRAFT

62. NERVE TRANSFER (ANASTOMOSIS)

63. MUSCLE FLAP

64. BELL’S PALSY Most common diagnosis of acute facial paralysis
Diagnosis is by exclusion

65. PATHOLOGY
Edema of the facial nerve sheath along its entire intratemporal course (Fallopian canal)

66. ETIOLOGY
Vascular vs. viral

67. CLINICAL FEATURES Sudden onset unilateral FP Partial or complete
No other manifestations apart from occasional mild pain
May recur in 6 – 12%

68. PROGNOSIS 80% complete recovery 10% satisfactory recovery
10% no recovery

69. TREATMENT Reassurance Eye protection Physiotherapy
Medications ( steroids, antivirals vasodilators)
Surgical decompression in selected cases

70. SURGICAL MANAGEMENT Debate over years Patients with 90% degeneration
Within 14 days of onset

71. THANK YOU