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Figure 13.1. Types of stapedial otosclerosis. (A) Anterior focus. (B) Posterior focus. (C) Circumferential. (D) Biscuit type (thick plate).
(E) Obliterative.
SECTION I — Diseases of Ear
Scan to play Otosclerosis and Its Management.
PATHOLOGY
Grossly, otosclerotic lesion appears chalky white, greyish
or yellow. Sometimes, it is red in colour due to increased
vascularity, in which case, the otosclerotic focus is active
and rapidly progressive.
Microscopically, spongy bone appears in the normally
dense enchondral layer of otic capsule. In immature active lesions, there are numerous marrow and vascular
spaces with plenty of osteoblasts and osteoclasts and a
lot of cement substance which stains blue (blue mantles)
with haematoxylin-eosin stain. Mature foci show less
vascularity and laying of more bone and more of fibrillar
substance than cementum, and is stained red.
SYMPTOMS
1. hearing loss. This is the presenting symptom and
usually starts in twenties. It is painless and progressive
with insidious onset. Often it is bilateral conductive type.
2. paracusis willisii. An otosclerotic patient hears bet-
ter in noisy than in quiet surroundings. This is because a
normal person will raise his voice in noisy surroundings.
3. tinnitus. It is more commonly seen in cochlear oto-
sclerosis and in active lesions.
3. Tuning fork tests show negative Rinne (i.e. BC > AC)
first for 256 Hz and then 512 Hz and still later, when
stapes fixation is complete, for 1026 Hz. Weber test will
be lateralized to the ear with greater conductive loss.
Absolute bone conduction may be normal. It is decreased in cochlear otosclerosis with sensorineural loss.
Pure tone audiometry shows loss of air conduction, more
for lower frequencies.
Bone conduction is normal. In some cases, there is
a dip in bone conduction curve. It is different at different frequencies but maximum at 2000 Hz and is called
Carhart’s notch (5 dB at 500 Hz, 10 dB at 1000 Hz, 15 dB
at 2000 Hz and 5 dB at 4000 Hz) (Figure 13.2). Carhart’s
notch disappears after successful stapedectomy.
Mixed hearing loss is not uncommon in otosclerosis.
There is loss in bone conduction with air-bone gap.
Speech audiometry reveals normal discrimination
score except in those with cochlear involvement.
4. Vertigo. It is an uncommon symptom.
5. speech. Patient has a monotonous, well-modulated
soft speech.
SIGNS
1. Tympanic membrane is quite normal and mobile. Sometimes, a reddish hue may be seen on the promontory
through the tympanic membrane (Schwartze sign). This
is indicative of active focus with increased vascularity.
2. Eustachian tube function is normal.
Figure 13.2. Otosclerosis left ear. Note dip at 2000 Hz in bone
conduction (Carhart’s notch).
Figure 13.3. (A) Before removal of stapes. (B) Stapes removed and
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replaced by a teflon piston.
Tympanometry may be normal in early cases but later
shows a curve of ossicular stiffness. Stapedial reflex becomes absent when stapes is fixed (see p. 26).
DIFFERENTIAL DIAGNOSIS
Otosclerosis should be differentiated from other causes
of conductive deafness particularly serous otitis media,
adhesive otitis media, tympanosclerosis, attic fixation of
head of malleus, ossicular discontinuity or congenital stapes fixation.
TREATMENT
medical. There is no medical treatment that cures otosclerosis. Sodium fluoride has been tried to hasten the
maturity of active focus and arrest further cochlear loss,
but controversies exist and this treatment is not recommended generally.
surgical. Stapedectomy/stapedotomy with a placement of
prosthesis is the treatment of choice. Here the fixed otosclerotic stapes is removed and a prosthesis inserted between the incus and oval window (Figure 13.3). Prosthesis employed may be a teflon piston, stainless steel piston,
platinum–teflon or titanium–teflon piston (Figure 13.4).
In 90% of patients, there is good improvement in hearing
after stapedectomy.
Chapter 13 — Otosclerosis (Syn. Otospongiosis)
selection oF patients For stapes surgery. Hear-
ing threshold for air conduction should be 30 dB or
worse. (It is this level when patient starts feeling socially
handicapped.)
Average air-bone gap should be at least 15 dB with
Rinne negative for 256 and 512 Hz.
Speech discrimination score should be 60% or more.
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Contraindications to Stapes Surgery
1. The only hearing ear.
2. Associated Ménière’s disease. When there is history of
vertigo with clinical evidence of Ménière’s disease in
an otosclerotic patient, there are more chances of sensorineural hearing loss after stapedectomy.
3. Young children. Recurrent eustachian tube dysfunction is common in children. It can displace the prosthesis or cause acute otitis media. Also the growth of
otosclerotic focus is faster in children leading to reclosure of oval window.
4. Professional athletes, high construction workers, divers and frequent air travellers. Stapes surgery has the
risk to cause postoperative vertigo and/or dizziness
and thus interfere with their profession; or frequent
air pressure changes may damage the hearing or cause
severe vertigo.
5. Those who work in noisy surroundings. After stapedectomy, they would be more vulnerable to get sensorineural hearing loss due to noise trauma.
6. Otitis externa, tympanic membrane perforation and
exostosis are relative contraindications. Stapedectomy
can be done after they have been treated first for above
conditions. Similarly, stapedectomy is avoided during
pregnancy.
The operation is preferably done under local anaesthesia.
Steps of Stapedectomy (Figure 13.5)
1. Meatal incision and elevation of the tympanomeatal
flap.
2. Exposure of stapes area. This may require removal of
posterosuperior bony overhang of the canal.
3. Removal of stapes superstructure.
4. Creation of a hole in the stapes footplate (stapedotomy) or removal of a part of footplate (stapedectomy).
5. Placement of prosthesis.
6. Repositioning the tympanomeatal flap.
Figure 13.4. Stapes prostheses. (A) Teflon piston. (B) Platinum–
teflon piston. (C) Titanium–teflon piston.
Complications of Stapedectomy
1. Tear of tympanomeatal flap and later perforation of
tympanic membrane
2. Injury to chorda tympani with taste disturbance particularly if opposite chorda was earlier injured
3. Incus dislocation
4. Injury to facial nerve
5. Vertigo
a. Early in postoperative period (intraoperative trau-
ma, serous labyrinthitis, long prosthesis)
b. Late due to perilymph fistula and benign paroxys-
mal positional vertigo
6. Perilymph fistula/granuloma
7. Conductive loss
a. Short prosthesis
b. Loose prosthesis
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SECTION I — Diseases of Ear
Figure 13.5. Steps of stapedectomy (see text).
c. Displacement of prosthesis
d. Incus erosion (late)
8. Sensorineural hearing loss
a. Intraoperative trauma
b. Labyrinthitis
c. Perilymph fistula/granuloma
9. Dead ear
Two per cent of patients undergoing this operation
may suffer sensorineural loss. Slowly progressive high frequency loss is seen in long-term follow-up. One in 200
patients may get a totally “dead” ear.
Stapes mobilization is no longer done these days as it
gives temporary results; refixation being quite common.
Lempert’s fenestration operation is almost outdated now.
Here an alternative window is created in the lateral semicircular canal to function for the obliterated oval window.
It has the disadvantage of a postoperative mastoid cavity
and an inherent hearing loss of 25 dB which cannot be
corrected.
hearing aid. Patients who refuse surgery or are unfit for
surgery can use hearing aid. It is an effective alternative.
Chapter 14
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Facial Nerve and Its Disorders
ANATOMY AND FUNCTIONS
OF FACIAL NERVE
Facial nerve runs from pons to parotid. It is a mixed nerve
having motor and a sensory root. The latter is also called
the nerve of Wrisberg and carries secretomotor fibres to
the lacrimal gland and salivary glands, and brings fibres
of taste and general sensation. Thus there are two efferent and two afferent pathways. Components of the facial
nerve include:
1. Special visceral efferent forms the motor root and
supplies all the muscles derived from the second
branchial arch, i.e. all the muscles of facial expression,
auricular muscles (now vestigial), stylohyoid, posterior
belly of digastric and the stapedius.
2. General visceral efferent supplies secretomotor fibres
to lacrimal, submandibular and sublingual glands and
the smaller secretory glands in the nasal mucosa and
the palate.
3. Special visceral afferent brings taste from the anterior
two-thirds of tongue via chorda tympani and soft and
hard palate via greater superficial petrosal nerve. Taste
is carried to the nucleus of tractus solitarius.
4. General somatic afferent brings general sensation
from the concha, posterosuperior part of external canal and the tympanic membrane. These fibres account
for vesicular eruption in herpes zoster infection of the
geniculate ganglion. It also brings proprioceptive sensation from the facial muscles.
NUCLEUS OF FACIAL NERVE
Motor nucleus of the nerve is situated in the pons. It receives fibres from the precentral gyrus. Upper part of the
nucleus which innervates forehead muscles receives fibres
from both the cerebral hemispheres, while the lower part
of nucleus which supplies lower face gets only crossed
fibres from one hemisphere. The function of forehead
is preserved in supranuclear lesions because of bilateral
innervation. Facial nucleus also receives fibres from the
thalamus by alternate routes and provides involuntary
control to facial muscles. The emotional movements
such as smiling and crying are thus preserved in supranuclear palsies because of these fibres from the thalamus
(Figure 14.1).
COURSE OF FACIAL NERVE
Motor fibres take origin from the nucleus of VIIth nerve,
hook round the nucleus of VIth nerve and are joined by
the sensory root (nerve of Wrisberg). Facial nerve leaves the
brainstem at pontomedullary junction, travels through
posterior cranial fossa and enters the internal acoustic
meatus. At the fundus of the meatus (lateral most part of
meatus), the nerve enters the bony facial canal, traverses
the temporal bone and comes out of the stylomastoid foramen. Here it crosses the styloid process and divides into
terminal branches. The course of the nerve (Figure 14.2)
can thus be divided into three parts.
1. intracranial Part. From pons to internal acoustic
meatus (15–17 mm).
2. intratemporal Part. From internal acoustic meatus to stylomastoid foramen. It is further divided into:
(a) Meatal segment (8–10 mm). Within internal acoustic
meatus.
(b) Labyrinthine segment (4.0 mm). From fundus of mea-
tus to the geniculate ganglion where nerve takes a
turn posteriorly forming a “genu.” The nerve in the
labyrinthine segment has the narrowest diameter
(0.61–0.68 mm) and the bony canal in this segment
is also the narrowest. Thus oedema or inflammation
can easily compress the nerve and cause paralysis.
This is also the shortest segment of the nerve.
(c) Tympanic or horizontal segment (11.0 mm). From genic-
ulate ganglion to just above the pyramidal eminence.
It lies above the oval window and below the lateral
semicircular canal.
(d) Mastoid or vertical segment (13.0 mm). From the pyra-
mid to stylomastoid foramen. Between the tympanic and mastoid segments is the second genu of the
nerve.
3. extracranial Part. From stylomastoid foramen to
the termination of its peripheral branches.
BRANCHES OF FACIAL NERVE
1. greater superFicial Petrosal NerVe. It arises from
geniculate ganglion and carries secretomotor fibres to lacrimal gland and the glands of nasal mucosa and palate.
2. nerVe to Stapedius. It arises at the level of second
genu and supplies the stapedius muscle.
3. chorda Tympani. It arises from the middle of vertical
segment, passes between the incus and neck of malleus,
and leaves the tympanic cavity through petrotympanic
fissure. It carries secretomotor fibres to submandibular
and sublingual glands and brings taste from anterior twothirds of tongue.
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Figure 14.1. Forehead receives bilateral innervation and is thus
saved in supranuclear paralysis. Emotional movements controlled by
thalamo-nuclear fibres are also preserved.
SECTION I — Diseases of Ear
6. muscular Branches. To stylohyoid and posterior
belly of digastric.
7. peripheral Branches. The nerve trunk, after crossing the styloid process, forms two divisions, an upper
temporofacial and a lower cervicofacial, which further divide into smaller branches. These are the temporal, zygomatic, buccal, mandibular and cervical and together form
pes anserinus (goose-foot). They supply all the muscles of
facial expression.
BLOOD SUPPLY OF FACIAL NERVE
It is derived from four blood vessels: (i) Anterior-inferior
cerebellar artery supplies the nerve in cerebellopontine
angle; (ii) labyrinthine artery, branch of anterior-inferior
cerebellar artery, which supplies the nerve in internal
auditory canal; (iii) superficial petrosal artery, a branch of
middle meningeal artery, which supplies geniculate ganglion and the adjacent region; and (iv) stylomastoid artery,
branch of posterior auricular artery, which supplies the
mastoid and tympanic segment. All the arteries form an
external plexus which lies in the epineurium and feeds a
deeper intraneural internal plexus (Figure 14.3).
Figure 14.2. (A) Course of facial nerve. Intratemporal part consists of
four segments: meatal (1), labyrinthine (2), tympanic (3) and mastoid
(4). (B) Branches of facial nerve on face.
4. communicating Branch. It joins auricular branch of
vagus and supplies the concha, retroauricular groove, posterior meatus and the outer surface of tympanic membrane.
5. posterior Auricular NerVe. It supplies muscles of
pinna, occipital belly of occipitofrontalis and communicates with auricular branch of vagus.
SURGICAL LANDMARKS OF FACIAL NERVE
For middle ear and mastoid surgery
1. Processus cochleariformis. It demarcates the geniculate ganglion which lies just anterior to it. Tympanic
segment of the nerve starts at this level.
2. Oval window and horizontal canal. The facial nerve
runs above the oval window (stapes) and below the
horizontal canal.
3. Short process of incus. Facial nerve lies medial to the
short process of incus at the level of aditus.
4. Pyramid. Nerve runs behind the pyramid and the posterior tympanic sulcus.
5. Tympanomastoid suture. In vertical or mastoid seg-
ment, nerve runs behind this suture.
6. Digastric ridge. The nerve leaves the mastoid at the
anterior end of digastric ridge.
For parotid surgery (Figure 14.4)
1. Cartilaginous pointer. The nerve lies 1 cm deep and
slightly anterior and inferior to the pointer. Cartilaginous pointer is a sharp triangular piece of cartilage of
the pinna and “points” to the nerve.
2. Tympanomastoid suture. Nerve lies 6–8 mm deep to
this suture.
3. Styloid process. The nerve crosses lateral to styloid
process.
4. Posterior belly of digastric. If posterior belly of digastric muscle is traced backwards along its upper border to its attachment to the digastric groove, nerve is
found to lie between it and the styloid process.
VARIATION AND ANOMALIES OF FACIAL
NERVE (FIGURE 14.5)
1. Bony dehiscence. This is the most common anomaly. Dehiscence (absence of bony cover) occurs
most commonly in tympanic segment over the oval
Chapter 14 — Facial Nerve and Its Disorders
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101
window. It also occurs near the region of geniculate
ganglion or in the region of retrofacial mastoid cells.
A dehiscent nerve is prone to injury at the time of
surgery or gets easily involved in mastoid and middle
ear infections.
2. Prolapse of nerve. The dehiscent nerve may prolapse
over the stapes and make stapes surgery or ossicular
reconstruction difficult.
3. Hump. The nerve may make a hump posteriorly near
the horizontal canal making it vulnerable to injury
while exposing the antrum during mastoid surgery.
4. Bifurcation and trifurcation. The vertical part of
facial nerve divides into two or three branches, each
occupying a separate canal and exiting through individual foramen.
5. Bifurcation and enclosing the stapes. The nerve
divides proximal to oval window—one part passing
above and the other below it and then reuniting.
6. Between oval and round windows. Just before oval
window the nerve crosses the middle ear passing between oval and round windows.
Anomalies of the nerve are more common in congeni-
tal ears; utmost care should be taken while operating cases of microtia or other congenital conditions of the ear.
Figure 14.3. Blood supply of facial nerve. (1) Cerebellopontine angle: Anterior-inferior cerebellar artery. (2) Internal auditory canal:
Labyrinthine artery. (3) Geniculate ganglion and adjacent facial nerve:
Superficial petrosal. (4) Mastoid segment: Stylomastoid artery. Thus
both carotid and vertebrobasilar systems supply the nerve and meet
at labyrinthine segment.
Figure 14.4. Surgical landmarks of the facial nerve in parotid
surgery.
STRUCTURE OF NERVE
From inside out, a nerve fibre consists of axon, myelin
sheath, neurilemma and endoneurium. A group of nerve
fibres is enclosed in a sheath called perineurium to form a
fascicle and the fascicles are bound together by epineurium
(Figure 14.6).
SEVERITY OF NERVE INJURY
Degree of nerve injury will determine the regeneration of
nerve and its function. Earlier nerve injuries were divided
into:
1. Neurapraxia, a conduction block, where flow of axoplasm through the axons was partially obstructed.
2. Axonotmesis—injury to axons.
3. Neurotmesis—injury to nerve.
Sunderland classified nerve injuries into five degrees of
severity based on anatomical structure of the nerve and
this classification is now widely accepted.
1°= Partial block to flow of axoplasm; no morphologi-
cal changes are seen. Recovery of function is complete
(neurapraxia).
2°= Loss of axons, but endoneurial tubes remain intact.
During recovery, axons will grow into their respective
tubes, and the result is good (axonotmesis).
3°= Injury to endoneurium. During recovery, axons of
one tube can grow into another. Synkinesis can occur
(neurotmesis).
4°= Injury to perineurium in addition to above. Scarring
will impair regeneration of fibres (partial transection).
5°= Injury to epineurium in addition to above (complete
nerve transection).
The first three degrees are seen in viral and inflamma-
tory disorders while fourth and fifth are seen in surgical
or accidental trauma to the nerve or in neoplasms.
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SECTION I — Diseases of Ear
Figure 14.5. Variations and abnormalities in the course of facial nerve. (A) Normal, (B) bony dehiscence, (C) hump posteriorly (near the second
genu), (D) bifurcation, (E) trifurcation, (F) bifurcating and reuniting round the oval window and (G) the nerve passing between the oval and
round windows.
Figure 14.6. Structure of a nerve. (A) Cross section of nerve. (B) Structure of a nerve fibre, longitudinal and cross-sectional views.
Chapter 14 — Facial Nerve and Its Disorders
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ELECTRODIAGNOSTIC TESTS
These tests are useful to differentiate between neurapraxia
and degeneration of the nerve. They also help to predict
prognosis and indicate time for surgical decompression
of the nerve.
1. minimal NerVe Excitability Test. The nerve is
stimulated at steadily increasing intensity till facial twitch
is just noticeable. This is compared with the normal side.
There is no difference between the normal and paralyzed
side in conduction block. In other injuries, where degeneration sets in, nerve excitability is gradually lost. When the
difference between two sides exceed 3.5 m amp, the test
is positive for degeneration. Degeneration of fibres cannot
be detected earlier than 48–72 h of its commencement.
2. maximal Stimulation Test (mst). This test is simi-
lar to the minimal nerve excitability test but instead of
measuring the threshold of stimulation, the current level
which gives maximum facial movement is determined
and compared with the normal side. Response is visually
graded as equal, decreased or absent. Reduced or absent
response with maximal stimulation indicates degeneration and is followed by incomplete recovery.
3. electroneuronography (enog). It is a sort of
evoked electromyography. The facial nerve is stimulated at
the stylomastoid foramen and the compound muscle action potentials are picked up by the surface electrodes. Supramaximal stimulation is used to obtain maximal action
potentials. The responses of action potentials of the paralyzed side are compared with that of the normal side on
similar stimulation and thus percentage of degenerating
fibres is calculated. Studies reveal that degeneration of 90%
occurring in the first 14 days indicates poor recovery of
function. Faster rate of degeneration occurring in less than
14 days has a still poorer prognosis. ENoG is most useful
between 4 and 21 days of the onset of complete paralysis.
4. electromyography (emg). This tests the motor
activity of facial muscles by direct insertion of needle
electrodes usually in orbicular oculi and orbicularis oris
muscles and the recordings are made during rest and voluntary contraction of muscle.
In a normal resting muscle, biphasic or triphasic po-
tentials are seen every 30–50 ms.
In a denervated muscle, spontaneous involuntary action potentials called fibrillation potentials are seen. They
appear 14–21 days after denervation. With regeneration
of the nerve after injury, polyphasic reinnervation potentials
replace fibrillation potentials. They appear 6–12 weeks
prior to clinical evidence of facial function and thus provide the earliest evidence of recovery.
Voluntary contraction causes motor discharge. Diminished or no response to voluntary contraction is seen after nerve injury.
Electromyography is useful in planning reanimation
procedures. Presence of normal or polyphasic potentials
after 1 year of injury indicates that reinnervation is taking
place and there is no need for reanimation procedure. If
fibrillation potentials are seen, it indicates intact motor
end plates but no evidence of reinnervation and need for
nerve substitution. Electrical silence indicates atrophy of
motor end plates and need for muscle transfer procedures
rather than nerve substitution.
Thus ENoG and EMG are complimentary and help to
prognosticate in cases of facial paralysis and in deciding
the procedure for reanimation, i.e. nerve substitution versus muscle transposition or sling operation.
CAUSES OF FACIAL PARALYSIS
The cause may be central or peripheral. The peripheral lesion may involve the nerve in its intracranial, intratemporal or extratemporal parts. Peripheral lesions are more
common and about two-thirds of them are of the idiopathic variety (Table 14.1).
A. IDIOPATHIC
1. Bell’s Palsy
Sixty to seventy-five per cent of facial paralysis is due to
Bell’s palsy. It is defined as idiopathic, peripheral facial pa-
ralysis or paresis of acute onset. Both sexes are affected with
TABLE 14.1 CAUSES OF FACIAL PARALYSIS
• Central
• Brain abscess
• Pontine gliomas
• Poliomyelitis
• Multiple sclerosis
• Intracranial part (cerebellopontine angle)
• Acoustic neuroma
• Meningioma
• Congenital cholesteatoma
• Metastatic carcinoma
• Meningitis
• Intratemporal part
• Idiopathic
– Bell palsy
– Melkersson syndrome
• Infections
– Acute suppurative otitis media
– Chronic suppurative otitis media
– Herpes zoster oticus
– Malignant otitis externa
• Trauma
– Surgical: Mastoidectomy and stapedectomy
– Accidental: Fractures of temporal bone
• Neoplasms
– Malignancies of external and middle ear
– Glomus tumour
– Facial nerve neuroma
– Metastasis to temporal bone (from cancer of breast,
bronchus, prostate)
• Extracranial part
• Malignancy of parotid
• Surgery of parotid
• Accidental injury in parotid region
• Neonatal facial injury (obstetrical forceps)
• Systemic diseases
• Diabetes mellitus
• Hypothyroidism
• Uraemia
• Polyarteritis nodosa
• Wegener’s granulomatosis
• Sarcoidosis (Heerfordt’s syndrome)
• Leprosy
• Leukaemia
• Demyelinating disease
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SECTION I — Diseases of Ear
equal frequency. Any age group may be affected though
incidence rises with increasing age. A positive family history is present in 6–8% of patients. Risk of Bell palsy is
more in diabetics (angiopathy) and pregnant women (retention of fluid).
aetiology
1. viraL InFection. Most of the evidence supports the
viral aetiology due to herpes simplex, herpes zoster or the
Epstein–Barr virus. Other cranial nerves may also be involved in Bell palsy which is thus considered a part of the
total picture of polyneuropathy.
2. vaScuLar ISchaeMia. It may be primary or secondary. Primary ischaemia is induced by cold or emotional
stress. Secondary ischaemia is the result of primary ischaemia which causes increased capillary permeability leading to exudation of fluid, oedema and compression of
microcirculation of the nerve.
3. hereDitary. The fallopian canal is narrow because of
hereditary predisposition and this makes the nerve susceptible to early compression with the slightest oedema. Ten per
cent of the cases of Bell palsy have a positive family history.
4. autoiMMune DiSorDer. T-lymphocyte changes have
been observed.
clinical Features (Figures 14.7 and 14.8 A,B ).
Onset is sudden. Patient is unable to close his eye. On attempting to close the eye, eyeball turns up and out (Bell
phenomenon). Saliva dribbles from the angle of mouth.
Face becomes asymmetrical. Tears flow down from the
eye (epiphora). Pain in the ear may precede or accompany
the nerve paralysis. Some complain of noise intolerance
Figure 14.7. Facial paralysis left side. Compare it with normal side.
(stapedial paralysis) or loss of taste (involvement of chorda tympani). Paralysis may be complete or incomplete.
Bell palsy is recurrent in 3–10% of patients.
diagnosis. Diagnosis is always by exclusion. All other
known causes of peripheral facial paralysis should be excluded. This requires careful history, complete otological
and head and neck examination, X-ray studies, blood
tests such as total count, peripheral smear, sedimentation
rate, blood sugar and serology.
Nerve excitability tests are done daily or on alternate
days and compared with the normal side to monitor
nerve degeneration.
Localizing the site of lesion (topodiagnosis) helps in
establishing the aetiology and also the site of surgical decompression of nerve, if that becomes necessary.
treatment
generaL
1. Reassurance.
2. Relief of ear pain by analgesics.
3. Care of the eye as outlined on p. 108. Eye must be pro-
tected against exposure keratitis.
4. Physiotherapy or massage of the facial muscles gives
psychological support to the patient. It has not been
shown to influence recovery. Active facial movements
are encouraged when there is return of some move-
ment to the facial muscles.
MeDicaL ManageMent
• Steroids. Their utility has not been proved beyond
doubt in carefully controlled studies. Prednisolone is
the drug of choice. If patient reports within 1 week,
the adult dose of prednisolone is 1 mg/kg/day divided
into morning and evening doses for 5 days. Patient is
seen on the fifth day. If paralysis is incomplete or is
recovering, dose is tapered during the next 5 days. If
paralysis remains complete, the same dose is continued for another 10 days and thereafter tapered in next
5 days (total of 20 days). Contraindications to use of
steroids include pregnancy, diabetes, hypertension,
peptic ulcer, pulmonary tuberculosis and glaucoma.
Steroids have been found useful to prevent incidence
of synkinesis, crocodile tears and to shorten the recovery time of facial paralysis. Steroids can be combined
with acyclovir for Herpes zoster oticus or Bell palsy.
• Other drugs. Vasodilators, vitamins, mast cell inhibitors
and antihistaminics have not been found useful.
Figure 14.8. Bell’s palsy left side: (A) Adult. (B) Child.
Scan to play Bell’s Palsy.
Figure 14.9. Ramsay–Hunt syndrome. Note facial palsy and small vesicles in the concha of the right side.
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surgical Treatment. Nerve decompression relieves
pressure on the nerve fibres and thus improves the microcirculation of the nerve. Vertical and tympanic segments
of nerve are decompressed. Some workers have suggested
total decompression including labyrinthine segment by
postaural and middle fossa approach.
Chapter 14 — Facial Nerve and Its Disorders
105
prognosis. Eighty-five to ninety per cent of the patients
recover fully. Ten to fifteen per cent recover incompletely and may be left with some stigmata of degeneration.
Recurrent facial palsy may not recover fully. Prognosis is
good in incomplete Bell palsy (95% complete recovery)
and in those where clinical recovery starts within 3 weeks
of onset (75% complete recovery).
2. Melkersson Syndrome
It is also an idiopathic disorder consisting of a triad of
facial paralysis, swelling of lips and fissured tongue. Paralysis may be recurrent. Treatment is the same as for Bell
palsy.
• Recurrent facial palsy. Recurrent facial palsy is seen
in Bell palsy (3–10% cases), Melkersson syndrome,
diabetes, sarcoidosis and tumours. Recurrent palsy on
the same side may be caused by a tumour in 30% of
cases.
• Bilateral facial paralysis. Simultaneous bilateral fa-
cial paralysis may be seen in Guillain-Barré syndrome,
sarcoidosis, sickle cell disease, acute leukaemia, bulbar
palsy, leprosy and some other systemic disorders.
B. INFECTIONS
Herpes Zoster Oticus (Ramsay–Hunt
Syndrome)
There is facial paralysis along with vesicular rash in the
external auditory canal and pinna (Figure 14.9). There
may also be anaesthesia of face, giddiness and hearing
impairment due to involvement of Vth and VIIIth nerves.
Treatment is the same as for Bell palsy.
Infections of Middle Ear (see p. 89)
Malignant Otitis Externa (see p. 55)
Figure 14.10. (A) A longitudinal fracture runs along the axis of petrous pyramid. Typically, it starts at the squamous part of temporal
bone, runs through the roof of the external ear canal and middle ear
towards the petrous apex and to the foramen lacerum. (B) Transverse
fracture. It runs across the axis of petrous. Typically, it begins at the
foramen magnum, passes through occipital bone, jugular fossa and
petrous pyramid, ending in the middle cranial fossa. It may pass medial, lateral or through the labyrinth.
C. TRAUMA
1. Fractures of Temporal Bone
Fractures of temporal bone may be longitudinal, transverse or mixed (Figures 14.10 and 14.11). Facial palsy is
seen more often in transverse fractures (50%). Paralysis is due to intraneural haematoma, compression by a
bony spicule or transection of nerve. In these cases, it
is important to know whether paralysis was of immediate or delayed onset. Delayed onset paralysis is treated
conservatively like Bell palsy while immediate onset paralysis may require surgery in the form of decompression, re-anastomosis of cut ends or cable nerve graft
(Table 14.2).
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