made easy

3. You wake up one morning,
and your face feels stiff and
odd. When you look in a
mirror, half your face appears
to droop. You can only
manage half a smile, your eye
is dripping tears and doesn't
want to close. What in the
world is going on?

4.  Charles Bell
› Well known for his
studies on the nervous
system and the brain
› In the 19th century
discovered that lesions
of the 7th cranial nerve
causes facial paralysis

5. The 7th cranial nerve is paired
with the
structure that travels through
a narrow,
bony canal (called the
Fallopian canal) in the skull
beneath the ear
to the muscles on each side of
the face.
The nerve is mostly encased in
this bony shell.

6. Each nerve controls:
› Eye blinking and closing
› Facial expressions
 Smiling and frowning
› Tear glands
› Saliva glands
› Muscle of small bone in middle of ear called the
stapes
› Taste sensations

8.  Upper facial territory is supplied by bilateral motor
cortices
 Lower facial territory is supplied only by contralateral
motor cortex
 Therefore, unilateral central lesions spare upper face
 Lesions distal to geniculate ganglion
› Mostly motor abnormalities
 Lesions proximal to geniculate ganglion
› Motor, gustatory & autonomic abnormalities

9. Sunderland classification of nerve
injury
1° damage = Compression
2° damage = Interruption of axoplasm
3° damage = Disruption of myelin
4° damage = Disruption of perineurium,
myelin and axon
5° damage = Transection of nerve

11.  Characterized by:
› Peripheral facial paralysis
› Acute benign cranial polyneuritis
Acute disorder characterized by a
disruption of the motor branches of
cranial nerve VII on one side of the
face. (in absence of stroke)

12.  Varies from person to
person
› Comes on suddenly
› Mild to total paralysis
 Weakness, twitching on one
of
both sides of the face
› Facial and eyelid droop
› Drooling
› Dryness of eye or mouth
› Impairment of taste
› Excessive tearing of eye

13.  Pain or discomfort in jaw and behind
the ear
 Ringing in one or both ears
 Loss of taste
 Headache
 Hypersensitivity to sound
 Impaired speech
 Dizziness
 Difficulty eating and drinking

14.  Often accompanied by an outbreak
of herpes vesicles in or around the ear.
 Pain around or behind the ear
 Fever, tinnitus, hearing deficits
 Flaccidity of the affected side of the
face with drooping of the mouth
accompanied by drooling DT paralysis
of the facial nerve (motor branches)

15.  Inability to close the eyelids, with an upward
movement of the eyeball when closure is
attempted; lower lid may turn out
 Wide palpebral fissure (opening between
eyelids)
 Flattening of the nasolabial fold
 Inability to smile, frown, or whistle
 Unilateral loss of taste
 Altered chewing ability; loss of or excessive
tearing

17.  Grade I - Normal
 Grade II - Mild dysfunction, slight weakness on close inspection,
normal symmetry at rest
 Grade III - Moderate dysfunction, obvious but not disfiguring
difference between sides, eye can be completely closed with
effort
 Grade IV - Moderately severe, normal tone at rest, obvious
weakness or asymmetry with movement, incomplete closure of
eye
 Grade V - Severe dysfunction, only barely perceptible motion,
asymmetry at rest
 Grade VI - No movement

18.  To determine the anatomical
level of a peripheral lesion
 Lacrimation  Geniculate
ganglion
 Stapedius reflex  motor nerve of
stapedius muscle
 Taste  chorda tympani

19.  Geniculate ganglion & petrosal nerve
function test
 Schirmer’s test +ve when
› Affected side shows less than half
the amount of lacrimation seen on
the normal side
› Sum of the lengths of wetted filter
paper for both eyes less than 25 mm
 Lesion at or proximal to the geniculate
ganglion

21.  Nerve to stapedius muscle test
 Impedance audiometry can record
the presence or absence of
stapedius muscle contraction to
sound stimuli 70 to 100 dB above
hearing threshold
 An absence reflex or a reflex less
than half the amplitude is due to a
lesion proximal to stapedius nerve

22.  Chorda tympani nerve test
 Solution of salt, sugar, citrate, quinine or
Electrical stimulation
 Compares amount of current require for a
response each side of tongue
 Normal : difference < 20 uAmp (thresholds
differening by more than 25%= abnormal)
 Total lack of Chorda tympani : No response
at 300 uAmp
 Disadvantage : False +ve in acute phase of
Bell’s palsy

24.  It occurs when the facial nerve is swollen,
inflamed, or compressed

25.  Mostly unknown
 May be caused by a viral infection
› Viral meningitis
› Herpes simplex
 Influenza
 Headaches
 Chronic ear infections
 High blood pressure
 Diabetes
 Sarcoidosis
 Tumors
 Lyme disease
 trauma

26.  Affects 40,000 Americans each year
› Men and women equally affected
› Can occur at any age
 Mostly after 15 and before 60 y/o
 Occurs more often in people who:
› Are pregnant
› Are diabetic
› Have an upper respiratory infection

27.  Psychological withdrawal DT
changes in appearance,
malnutrition or dehydration,
mucous membrane trauma,
corneal abrasion, muscle
stretching, and facial spasms and
contractures.

28.  There are no specific lab tests to confirm
diagnosis
 Will exam for upper and lower facial
weakness
 Electromyography
› Confirm presence of damage and determine
severity
 MRI and CT
› r/o causes of pressure on nerve

29.  No real Treatment
› Symptoms usually subside
 Anti-inflammatory and an antiviral
› Prednisone and acyclovir
 Increases the chance of recovery
 Acupuncture and surgery
› For long term paralysis

30.  Hard to close eye
› Use and eye patch
› Eye drops
› Tape eye shut when sleeping

31.  Corticosteroids- drug of choice
 Prednisone may be started immediately!
› Best if initiated before paralysis is complete
› Taper off over 2 weeks
› Decrease edema and pain
Analgesics may be needed for pain
Antivirals : Acyclovir (Zovirax) and Famvir
because HSV is implicated in 70% of cases.

32.  Outcome is good!!!
 Total recovery depends on amount of damage to
nerve
 Improvement is gradual
 Usually start to get better after 2 weeks of onset
and most recover completely within 3 to 6 months.
 In a few cases, the symptoms may never
completely disappear.
 In rare cases, the disorder may recur, either on the
same or the opposite side of the face.

33.  Clinical features
› Slower onset of symptoms
› Bilateral
› Recurrence
 Numbness is not unusual
 Progression beyond seven
days suggests another
cause

34.  Lyme disease (borreliosis)
› Endemic areas (Northeast USA, central
Europe, Scandinavia, Canada)
› Consider in children w/atypical facial palsy
 Imaging: small white matter lesions similar
to multiple sclerosis, enhancement of
facial & other cranial nerves
 Bilateral facial paralysis: 25%
 Important to make diagnosis early
because it is curable early w/antibiotics

35.  Caused by reactivation varicella zoster virus
(herpes virus type 3)
 Facial paralysis + hearing loss +/- vertigo
› Herpes zoster oticus
 Two-thirds of patients have rash around ear
 Other cranial nerves, particularly trigeminal nerves
(5th CN) often involved
 Worse prognosis than Bell’s (complete recovery:
50%)
 Important cause of facial paralysis in children
6-15 years old

36.  Acute facial paralysis may result from
bacterial or tuberculous infection of middle
ear, mastoid & necrotizing otitis externa
 Incidence of facial paralysis with otitis
media: 0.16%
› Infection extends via bone dehiscences to nerve
in fallopian canal leading to swelling,
compression & eventually vascular compromise
& ischemia
 Immune compromised patients are at risk
for pseudomona infection
 Poor prognosis (complete recovery is < 50%)

37.  Most acute post traumatic facial palsies are
due to t-bone fractures
 Historically fractures classified as
longitudinal or transverse with transverse
carrying risk of permanent paralysis
› Longitudinal fracture usually leads to temporary
paralysis from concussion & swelling of nerve
› Transverse fracture can lead to transection of
nerve
 In all types of paralysis due to fracture,
usually the region of geniculate ganglion is
involved

38.  27% of patients with tumors involving the
facial nerve develop acute facial paralysis
 Most common causes: schwannomas,
hemangiomas (usually near geniculate
ganglion) & perineural spread such as with
head and neck carcinoma, lymphoma &
leukemia
 Other neoplasms can also involve the facial
nerve
› Adults: metatstatic disease, glomus tumors,
vestibular schwannomas & meningiomas
› Children: eosinophilic granuloma & sarcomas

39.  Guillain-Barre Syndrome
› Ascending paralysis
 Iatrogenic
› Temporal bone surgery
 Excision of vestibular schwannoma
has <10% chance of paralysis
 Middle ear surgeries
› Babies who required forceps delivery
 >90% recovery

40.  Acute episodes of facial paralysis
› Facial swelling
› Fissured tongue
 “Scrotal” tongue
 Very rare
 Familial but sporadic
› Usually begins in adolescence
 Leads to facial disfigurement
 No definite therapy