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140 Disorders of the Auditory System
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a propensity to bleed when manipulated.
This granulation tissue may also appear
polypoid, and this polyp may extend into
the external auditory canal. The presence
of granulation tissue typically indicates
a secondary infection. Bone erosion generally occurs along the scutum or posterior bony wall and ossicular erosion may
be identified when any debris has been
removed. Pneumatic otoscopy with a fistula test can also reveal bony erosion of
the horizontal semicircular canal. A tuning fork exam may indicate a significant
conductive hearing loss.
The utilization of imaging in the
case of chronic otitis media varies greatly
among otologists. Radiographic imaging of the temporal bone can be helpful
in delineating anatomy and may provide
some information regarding the extent
of disease. High-resolution, thin slice CT
of the temporal bone without contrast is
frequently utilized if there are atypical
symptoms, complications of otitis media,
or suspicion of bony erosion of the tegmen, facial nerve, or the labyrinth. Computed tomography scans can also be particularly useful in preoperative planning
for revision surgical procedures.
Audiologic Management
Similar to other middle ear disorders,
patients with cholesteatomas will require
amplification if traditional medical management is unsuccessful.
Medical Management
Chronic otitis media requires close clinical follow-up. Subtle changes on examination or in history may herald progression
of the disease. With the use of otomicros-
copy, retraction pockets can be evaluated
and cleaned regularly. Some retraction
pockets may remain stable for years without progression or the development of
an invasive cholesteatoma, and monitoring may be the best treatment option for
those that are poor surgical candidates.
Generally, observation of a chronically
diseased ear is not recommended for children. Avoidance of water exposure to the
external auditory canal can be helpful in
decreasing moisture within a retraction
pocket and thus decrease bacterial overgrowth. Ototopical drops composed of
antibiotics with or without steroids are
commonly used to treat persistent drainage and inflammation associated with
chronic otitis media with cholesteatoma.
Placement of a PE tube can aerate the
middle ear and may prevent progression of tympanic membrane retraction.
Although medical treatment can alleviate
the symptoms of cholesteatomas, it does
not address the etiology of the problem.
Irreversible damage to the middle ear,
which is often the case in chronic otitis
media with cholesteatoma, requires surgical intervention.
The purpose of surgical treatment of
cholesteatoma is to create a safe, dry ear.
A secondary goal of surgical intervention is
the restoration of hearing. Tympanoplasty
is a surgical procedure in which disease is
removed from the middle ear and a weakened or perforated tympanic membrane is
repaired. Auricular perichondrium, with
or without cartilage, and temporalis fascia are commonly used to repair and reinforce the tympanic membrane. Mastoidectomy, which may be performed along
with tympanoplasty, involves the removal
of chronic disease within the mastoid air
cells. A complete mastoidectomy, or canal
wall up (CWU) mastoidectomy, involves
careful removal of the cholesteatoma and
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diseased mucosa within the air cells of the
mastoid by drilling the cholesteatoma and
any diseased mucosa away. Using this
approach, the posterior canal wall is left
intact and candidates for this procedure
have an aerated mastoid and reasonable
Eustachian tube function. It is imperative
to remove all of the cholesteatoma during
the procedure because even a microscopic
remnant of squamous debris within the
mastoid or middle ear can lead to a recurrence. It is impossible to evaluate the mastoid cavity in the clinic following a CWU
mastoidectomy, thus a relook procedure
may be recommended in 6 to12 months
to inspect for recurrent disease. During a
relook procedure, the status of the ossicles
can be examined and ossiculoplasty can
be performed to restore ossicular continuity and function, if needed. A CWU
mastoidectomy can only be performed in
a reliable patient as failure to follow up
can result in a devastating progression
of recurrent disease. The advantage of a
CWU mastoidectomy is that the anatomy
of the external auditory ear and tympanic membrane is restored; thus, water
exposure of the external auditory canal
following the surgical procedure is safe.
The ear that has undergone a CWU mastoidectomy also can be amplified with a
hearing aid more easily than one that has
undergone alternative treatments.
Historically, mastoidectomy included
removal of the posterior wall of the external auditory canal to create a wide-open
cavity that could easily be cleaned and
evaluated for recurrence in a clinic setting. This procedure is now called a modified radical mastoidectomy, or canal wall
down (CWD) mastoidectomy. The indications for this procedure are the presence of recurrent disease, a labyrinthine
fistula, extensive destruction of the posterior canal wall by cholesteatoma, choles-
teatoma in an only hearing ear, recurrent
disease following CWU mastoidectomy,
a sclerotic mastoid, or a patient who is
unreliable or unlikely to follow through
with a relook procedure. The disadvantage of a CWD mastoidectomy is that the
ear must remain dry or significant infection can occur within the cavity. Also, the
mastoid bowl must be examined regularly
in the clinic to remove debris as this cavity cannot be self-cleaning by nature. This
procedure typically provides a safe ear in
which recurrence can be caught easily and
removed without significant risk or discomfort to the patient (Bennett, Warren,
& Haynes, 2006).
Case 4–5: Cholesteatoma
History
This 70-year-old male with a long-standing history of mastoiditis and meningitis
was seen for reevaluation due to the presence of chronic discharge from both ears
for the past 2 years. The patient’s medical conditions had resulted in diminished
hearing and he previously had been fitted with binaural amplification, which he
continues to use.
Audiology
A comprehensive audiologic examination revealed a severe to profound mixed
hearing loss in the left ear and a profound
mixed hearing loss in the right ear (Figure
4–5). Word recognition was 84% for the
left ear but could not be evaluated for the
right ear. Tympanometry indicated severely
reduced compliance and a normal volume
measurement for the right ear, while the left
ear presented with a large volume consistent with a tympanic membrane
perforation.
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Figure 4–5. Pure-tone air- and bone-conduction thresholds, speech audiometry, and tympanom-
etry results for a 70-year-old male with a right-sided cholesteatoma and a left-sided tympanic membrane perforation (Case 4–5). Results are shown for preoperative testing. There were no significant
audiologic changes in hearing sensitivity postoperatively.
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Medical Examination
The patient presented with an anterior
tympanic membrane perforation on the
left side. The right tympanic membrane
presented no visible landmarks due to
thickening. A CT examination was ordered
and showed a significant cholesteatoma
in the right ear. The cholesteatoma had
eroded a significant amount of bone and
had exposed the dura on the right side.
The left ear demonstrated significant fluid
and soft tissue swelling.
Impression
Right-sided cholesteatoma. This patient
presented with a significant mixed hearing loss in the right ear. Although a portion of the hearing loss is attributed to
the cholesteatoma, there is an underlying
permanent sensorineural component that
will not be corrected by surgery.
Audiologic Recommendations
and Management
It was recommended that the patient continue with the use of binaural amplification following medical management.
Medical Recommendations
and Management
Following medical and audiologic evaluation, it was recommended that the patient
undergo a right radical mastoidectomy.
Additional Comments
The patient chose to undergo the recommended surgical procedure (i.e., right radical mastoidectomy). Results of that surgery revealed an extensive cholesteatoma,
which had eroded much of the cochlea
and the horizontal semicircular canal in
the right ear. This was likely the source of
the patient’s prior history of meningitis.
The patient has done well since the surgery; however, no improvement in hearing was observed postoperatively due to
the extent of the damage (see Figure 4–5).
Case 4–6: Cholesteatoma
History
This 9-year-old male presented with a
long-standing history of intermittent otorrhea (drainage) and recurrent infection in
the left ear. The child reported difficulty
hearing out of the left ear. No other significant audiologic or otologic symptoms
were noted.
Audiology
A comprehensive audiologic examination revealed normal peripheral hearing
sensitivity for the right ear and a severe
rising to mild conductive hearing loss for
the left ear (Figure 4–6). Word recognition
was excellent bilaterally. Tympanometry
indicated reduced compliance for the left
ear and normal pressure, volume, and
compliance for the right ear.
Medical Examination
The patient presented with an obvious
pars flaccida cholesteatoma extending
into the attic in the left ear and a normal
appearing mastoid, pinna, ear canal, and
tympanic membrane without fluid, perforation, or retraction in the right ear.
Impression
Left-sided cholesteatoma.
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A
Figure 4–6. Pure-tone air- and bone-conduction thresholds, speech audiometry, and tympanom-
etry results for a 9-year-old with a left-sided cholesteatoma (Case 4–6). Results are shown for both
preoperative testing (A) and postoperative testing (B). continues
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B
Figure 4–6. continued
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Audiologic Recommendations
and Management
Reevaluation and possible amplification for
the left ear following medical management.
Medical Recommendations
and Management
It was recommended that the patient
undergo left mastoidectomy and tympanoplasty with possible ossicular chain
reconstruction.
Additional Comments
The patient’s parents chose to have their
son undergo the recommended surgery.
Results of that surgery revealed an extensive cholesteatoma, which required revision 5 months postoperatively. Audiologic
test results for the left ear following surgery revealed significant improvement in
hearing sensitivity, as well as improved
middle ear function in this ear (see Figure
4–6B). As the patient still presented with
a mild hearing loss on the left side, a mild
gain hearing aid was recommended.
PaRaganglioma tumoRs
Introduction
Paraganglioma tumors, also known as
glomus tumors, are benign, slow-growing,
and highly vascularized neoplasms that
may occur in various regions of the body.
They are the second most common benign
neoplasm of the temporal bone, after the
vestibular schwannoma. The understanding and resulting treatment of paragangliomas has evolved dramatically in the past
century. In 1941, while examining a series
of human temporal bones, Stacy Guild
identified a discrete collection of capillary
size vessels similar to the carotid body
adjacent to the jugular bulb and coursing
along the tympanic branch of the glossopharyngeal nerve (Jacobson’s nerve) and
the auricular branch of the vagus nerve
(Arnold’s nerve). He referred to these
masses as “glomus jugularie” (Guild,
1941). Rosenwasser recognized Guild’s
description and gave confirmation of a
distinct disease process as he reported on
the removal of a glomus jugulare tumor in
1945 (Rosenwasser, 1945). Initially, it was
thought that glomus tumors were vascular in origin; however, they actually arise
from a collection of neuroendocrine paraganglial cells originating from neural crest
cells that are surrounded by a dense collection of capillaries and venules (Gulya,
1993); hence, the term paraganglioma
emerged.
Paragangliomas may be present
throughout the body, but temporal bone
tumors are classified based on their location. Cervical paragangliomas occur adjacent to the carotid artery or cranial nerves
and include carotid body tumors and glomus vagale. Paragangliomas of the temporal bone include glomus jugulare and
glomus tympanicum tumors. Glomus jugulare tumors develop from paraganglial
tissue within the adventitia of the jugular
bulb (Gulya, 1993) and may extend from
the skull base into and through the temporal bone to cause significant morbidity. Glomus tympanicum tumors develop
from paraganglion adjacent to either
Jacobson’s nerve or Arnold’s nerve and
typically are confined to the middle ear
space but may extend into the mastoid
or external auditory canal. The ascending
pharyngeal artery provides the primary
blood supply to glomus tumors of the
temporal bone.
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Symptoms
The symptoms of paraganglioma tumors
of the temporal bone are variable and
develop gradually due to a slow growth
pattern. As a glomus tympanicum tumor
fills the middle ear, conductive hearing
loss, otalgia, and aural fullness may be
encountered. The hallmark symptom of
this highly vascular lesion is pulsatile
tinnitus, which is reported to be present in 76% of patients with paragangliomas (Woods, Strasnick, & Jackson, 1993).
Any patient with pulsatile tinnitus must
be fully evaluated for a paraganglioma
tumor. Destruction of the tympanic
membrane and bleeding can occur but
are uncommon. Expansion of the tumor
within the mastoid can compromise the
facial nerve leading to paralysis, and erosion of the labyrinth can occur, resulting
in vertigo and sensorineural hearing loss.
A glomus jugulare tumor may also affect
other cranial nerves, most commonly the
contents of the jugular foramen (Woods
et al., 1993). Glossopharyngeal nerve
injury typically presents as an absent or
decreased gag reflex with potential for
dysphagia due to loss of pharyngeal sensation. Vagus nerve injury may present
with dysphagia, hoarseness, and recurrent aspiration due loss of laryngeal sensation and unilateral vocal fold paralysis.
The accessory nerve, which innervates
the sternocleidomastoid and trapezius
muscles, can present as neck and shoulder weakness when it is compromised.
Finally, the hypoglossal nerve can be compromised, resulting in ipsilateral tongue
paralysis. Intracranial extension of the
tumor can result in mental status changes,
headache, visual changes, and strokelike
symptoms.
Paraganglioma tumors, due to their
neuroendocrine origin, may secrete vaso-
active catecholamines, which when present in significant amounts, may cause
hypertension, palpitations, diaphoresis,
and arrhythmias. These symptoms are
much more common in paragangliomas
of other regions of the body, such as an
adrenal gland pheochromocytoma. Paragangliomas of the head and neck are
reported to be actively hormone secreting in less than 4% of the cases (Erickson
et al., 2001).
Incidence and Prevalence
Paraganglioma tumors are rare lesions of
the temporal bone and occur at a rate of 1
per 1.3 million people (Moffat & Hardy,
1989). Paragangliomas typically are isolated lesions, but other tumors such as
contralateral lesions, carotid body tumors,
or glomus vagale tumors can occur in up
to 10% of patients (Spector, Ciralsky, &
Ogura, 1975). Neoplasms of neural crest
cell origin may also be found in 7% of these
patients (Spector, Maisel, & Ogura, 1974).
Glomus tumors are more common in Caucasians and in women (O’Leary, Shelton,
Giddings, Kwartler, & Brackmann, 1991).
They also have a predilection to be transmitted in an autosomal dominant pattern
with variable penetrance within families,
and these patients are at a higher risk of
multiple tumors (Horn & Hankinson, 1994).
Etiology and Pathology
Paragangliomas are composed of two cells
types. Chief cells, which are neuroendocrine cells, are filled with vasoactive compounds that can be secreted as described
previously. Sustentacular cells are similar
to Schwann cells and support the chief
cells. This cluster of cells is surrounded
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by a dense network of capillaries and
venules. This tumor is typically benign,
slow growing, and travels along the path
of least resistance. Traveling through
haversian canals of the bone and within
mastoid air space, these tumors gradually
erode the temporal bone. They can place
vital neural and vascular structures at risk
with their diffuse yet insidious growth;
thus, appropriate management of these
tumors has involved multidisciplinary
innovation and collaboration. Metastasis
of glomus tumors occurs in approximately
1% to 4% of the patients (Borsanyi, 1962;
Brown, 1985), and this condition appears
to be more prevalent in individuals with
familial inheritance of the disease.
Site of Lesion
Glomus tympanicum tumors are found in
the middle ear space and originate from
paraganglia traveling along Jacobson’s
or Arnold’s nerve on the promontory,
which is the bone overlying the basal turn
of the cochlea (Appendix 4F). Glasscock
and Jackson developed a classification
system for these tumors based on their
location within the middle ear space and
surrounding areas (Table 4–1) (Jackson,
Glasscock, & Harris, 1982).
Jugular paraganglioma tumors develop from the adventitia of the jugular
bulb just below the hypotympanum. Two
separate location classification systems
have been developed. Fisch first described
in 1979 a classification system that does
not distinguish between jugulare and
tympanicum tumors, but simply describes
tumor extension (Table 4–2) (Oldring &
Fisch, 1979). Glasscock and Jackson later
offered their glomus jugularae classification system (Table 4–3) (Jackson et al.,
1982). Both classification systems are used
widely today.
Audiology
On audiologic examination, patients may
present with virtually any pattern of hearing loss (conductive, mixed, or sensorineural), but in rare cases, the patient may
present with normal peripheral hearing
sensitivity. In a retrospective investigation, conductive hearing loss accounted
for nearly 76% of the hearing losses
observed (Fayad, Keles, & Brackmann,
2010). Additionally, tympanometry may
yield a variety of test results but has demonstrated utility in the evaluation of these
vascular lesions (Leveque, Bialostozky,
Blanchard, & Suter, 1979). One unique
Table 4–1. Glasscock-Jackson Glomus
Tympanicum Classification (1982)
Type I Mass limited to the promontory
Type II Mass fills the middle ear space
Type III Mass fills the middle ear and
extends into mastoid
Type IV Mass fills middle ear, mastoid, and
extends into the external auditory
canal
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Table 4 –2 . Fisch Glomus Classification (1979)
Class A Mass limited to the middle ear
Class B Mass limited to the middle ear and mastoid without
destruction of bone in the infralabyrinthine compartment
Class C1 Mass extends into infralabyrinthine compartment with
destruction of the jugular foramen and jugular bulb
Class C2 Mass extends into the infralabyrinthine compartment with
involvement of the vertical portion of the carotid canal
Class C3 Mass extends into the infralabyrinthine compartment with
involvement of the horizontal portion of the carotid canal
Class D1 Mass with up to 2 cm of intracranial extension
Class D2 Mass with greater than 2 cm of intracranial extension
Class D3 Mass with inoperable intracranial extension
Table 4 – 3. Glasscock-Jackson Glomus Jugulare Classification (1982)
Type I Mass involving the jugular bulb, middle ear, and mastoid
Type II Mass extends under the internal auditory canal
Type III Mass extends into the petrous apex
Type IV Mass extends into the clivus or infratemporal fossa
sign that may be observed during tympanometry is a pulsating beat, which can be
seen throughout the immittance recordings. This pulsation is typically synchronous with the patient’s heartbeat (Jerger
& Jerger, 1981).
Medical Examination
The examination of a patient with a paraganglioma glomus tumor must be careful
and thorough. Vital sign documentation
may uncover hypertension or tachycardia present from a secreting tumor. Oto-
scopic examination may reveal a bluish
or reddish mass behind the tympanic
membrane. Upon insufflation of the membrane one may see a blush of the mass,
which is known as Brown’s sign (Karas &
Kwartler, 1993). A paraganglioma tumor
may erode through the membrane and
present as a mass within the external
auditory canal. Biopsy of a polyp or mass
within the external auditory canal is not
advised in the outpatient clinic due to the
risk of brisk bleeding. A thorough cranial
nerve exam during the head and neck
exam is vital to document deficits due to
tumor extension.
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