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ORIGINAL SAC
ARTICLE
OBSTRUCTING LESIONS OF THE ENDOLYMPHATIC
AND DUCT MIMICKING MÉNIÈRE’S DISEASE
Obstructing lesions of the
endolymphatic sac and duct
mimicking Ménière’s disease
Ryan C. Cmejrek, MD; Cliff A. Megerian, MD
Abstract
In this retrospective case series and literature review,
we demonstrate that temporal bone lesions that obstruct
the endolymphatic sac or duct can cause symptoms of
Ménière’s disease. This finding is likely attributable to
endolymphatic hydrops; initially, such cases typically
masquerade as Ménière’s disease. Between July 1995 and
April 2002, a total of 379 patients were treated for an initial
diagnosis of Ménière’s disease at our institution. Among
this group, 3 patients were found to have an obstructing
lesion of the endolymphatic sac or duct that we felt was
causally related to their Ménière’s-like symptomatology.
We reviewed these cases and noted the similarities in each
patient’s presentation, including a common pathophysiology. On imaging studies, each patient had a different
pathologic lesion that involved the endolymphatic sac
or duct: patient 1 had a jugular megabulb, and she was
ultimately treated with vestibular nerve section; patient
2 had a cholesterol granuloma, which was treated with
surgical excision; patient 3 had an endolymphatic sac tumor that was treated with surgical excision. As has been
suggested in previous reports, not all cases of Ménière’s
disease are idiopathic. We conclude that obstruction of
the endolymphatic sac or vestibular aqueduct by a mass
lesion or vascular anomaly can lead to vestibulocochlear
pathology that mimics Ménière’s disease.
Introduction
Ménière’s disease is defined as the idiopathic syndrome
of endolymphatic hydrops that results in hearing loss, tinnitus, and episodic vertigo, and aural fullness.1 However,
there is continuing controversy in the literature regarding
From the Department of Otolaryngology–Head and Neck Surgery, University Hospitals of Cleveland, Case Western Reserve University
School of Medicine, Cleveland.
Reprint requests: Cliff A. Megerian, MD, Department of Otolaryngology–Head and Neck Surgery, University Hospitals of Cleveland,
11100 Euclid Ave., Cleveland, OH 44106. Phone: (216) 844-5500;
fax: (216) 844-5727; e-mail: [email protected]
Originally presented at the Middle Section meeting of the Triological
Society; Jan. 17-19, 2003; Indianapolis.
Volume 83, Number 11
the underlying pathophysiology of Ménière’s disease, and
most authors agree that not all cases are idiopathic. Recent
reports have suggested many possible etiologies, including autoimmune disease,2 viral infection,3 allergy,4 and
otosclerosis.5 In any event, impaired absorption or overproduction of endolymph is presumed to cause endolymphatic hydrops and associated Ménière’s symptomatology.
Similarly, vascular compression of the endolymphatic sac
and duct has been shown to be associated with Ménière’s
symptomatology in the presence of anatomic variants
such as jugular megabulb6 and an anomalous vein of the
vestibular aqueduct.7
Between July 1995 and April 2002, a total of 379 patients
had been seen in the otology–neurotology clinic with a
diagnosis of Ménière’s disease. In addition to the typical
medical and audiologic workup that was administered to all
patients, those with unilateral hearing loss underwent imaging studies in order to rule out retrocochlear disease.
In this article, we describe the cases of 3 patients who
initially presented with fluctuating sensorineural hearing
loss, tinnitus, episodic vertigo, and aural fullness and who
were initially diagnosed with Ménière’s disease. Further
evaluation and diagnostic imaging revealed that each had
a mass lesion of the temporal bone that had obstructed the
endolymphatic system. Patients 1 and 2 exhibited compression and erosion of the endolymphatic sac and duct by a
jugular megabulb and a cholesterol granuloma, respectively.
Patient 3 had two endolymphatic sac tumors that led to an
internal obstruction of the sac bilaterally.
We propose that any abnormal space-occupying lesion of
the temporal bone has the potential to cause endolymphatic
hydrops by obstructing the endolymphatic duct or sac.
Case reports
Patient 1. A 35-year-old woman presented with a 9-year
history of Ménière’s disease; she had a right-sided sensorineural hearing loss that had been sudden in onset and
slowly progressive over the years. The hearing loss was
accompanied by fluctuating nonpulsatile tinnitus, episodes
of vertigo that initially occurred a few times monthly, and
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CMEJREK, MEGERIAN
A
B
Figure 1. Patient 1. A: Preoperative audiogram shows the sloping mild-to-profound sensorineural hearing loss on the right and
essentially normal hearing on the left. Hearing levels for bone
conduction approximated those of air conduction (±10 dB). B:
Noncontrast axial CT of the temporal bones shows the massive
enlargement of the right jugular bulb (arrowhead).
aural fullness. Her symptoms had begun during a pregnancy,
and they were presumed to be of viral etiology. She had
sought intervention when her episodes of vertigo began to
occur almost daily. An audiogram showed essentially normal hearing in the left ear and a sloping mild-to-profound
sensorineural hearing loss in the right ear (figure 1, A). Her
speech discrimination score on the right was 0%. Magnetic
resonance imaging (MRI) was negative for retrocochlear
pathology.
After 3 years of conservative medical therapy (a low-salt
diet and a diuretic), the patient returned with worsening
vertigo and drop attacks. Findings on electronystagmog754
raphy were normal. However, computed tomography (CT)
of the temporal bones detected an enlargement of the right
jugular bulb with encroachment on the endolymphatic sac
and duct (figure 1, B). The patient underwent an endolymphatic shunt procedure, but her vertigo actually worsened
and was unresponsive to gentamicin therapy delivered to
the middle ear. Labyrinthectomy was recommended, but
the patient was hesitant to sacrifice the slight degree of
auditory perception that remained in her right ear. Instead,
she underwent a middle fossa vestibular nerve section.
At the 4-year follow-up, she remained free of disabling
vertigo.
Patient 2. A 45-year-old woman presented with a diagnosis of Ménière’s disease and a long history of fluctuating
hearing loss and tinnitus on the left. She reported a 7-year
history of episodic vertigo that had worsened over the
preceding 3 years; she also complained that sound was
distorted. She sought an otologic evaluation when she
began to experience an increasing feeling of pressure and
pain deep in her left ear.
An audiogram revealed a mild high-frequency sensorineural hearing loss on the right and a mild-to-moderate
low-frequency sensorineural hearing loss on the left (figure
2, A). MRI detected a complex mass on the left petrous
bone that extended to the posterior fossa and obstructed
the endolymphatic sac (figure 2, B). A slight dural erosion
was noted, but the internal auditory canal and cochlea were
not involved. Electrocochleography revealed a summatingpotential to action-potential (SP/AP) ratio of 0.56 on the
left and 0.15 on the right, findings that are consistent with
endolymphatic hydrops of the left ear.
The patient underwent a transtemporal resection of the lesion and dural reconstruction. The mass was not only locally
invasive, it had invaded the endolymphatic sac and duct,
as well. Final pathology was consistent with a cholesterol
granuloma. Postoperatively, the patient’s hearing declined
slightly, but her vertigo had completely resolved.
Patient 3. A 37-year-old woman with von Hippel-Lindau
disease presented with a diagnosis of Ménière’s disease
that manifested as hearing loss and tinnitus on the left
over several years and a recent increase in the frequency
of vertigo attacks to one a day. These symptoms had been
unresponsive to diet, diuretics, and other medications. The
patient had no other medical problems related to her von
Hippel-Lindau disease, and she was taking no medications.
Findings on physical examination were significant only
for a Weber test that lateralized to the right ear at 512 Hz.
An audiogram showed an upsloping sensorineural hearing
loss in the left ear (figure 3, A). Her speech discrimination
score on the left was 72%. MRI detected a left temporal
bone lesion posterior to the posterior semicircular canal
and a similar, smaller lesion on the right (figure 3, B).8
The patient underwent a left mastoidectomy and exploration of the left endolymphatic sac with tumor resection and
ENT-Ear, Nose & Throat Journal ■ November 2004
OBSTRUCTING LESIONS OF THE ENDOLYMPHATIC SAC AND DUCT MIMICKING MÉNIÈRE’S DISEASE
A
A
B
B
Figure 2. Patient 2. A: Preoperative audiogram reflects the mild
high-frequency sensorineural hearing loss on the right and the
mild-to-moderate low-frequency sensorineural hearing loss on
the left. Hearing levels for bone conduction approximated those
of air conduction (±10 dB). B: T2-weighted axial MRI shows the
cholesterol granuloma on the left petrous apex (arrowhead).
Figure 3. Patient 3. A: Preoperative audiogram demonstrates
normal hearing on the right and an upsloping mild-to-moderate
sensorineural hearing loss on the left. Hearing levels for bone
conduction approximated those of air conduction (±10 dB). B:
T1-weighted contrast-enhanced axial MRI shows the enhancing
lesion of the endolymphatic sac and duct on the left and a smaller,
similar lesion on the right.
preservation of the labyrinth and dura. Final pathology was
consistent with an endolymphatic sac tumor (previously
known as an aggressive papillary tumor). Postoperatively,
her vertigo resolved and her hearing improved. Although
electronystagmography 6 months postoperatively showed a
residual peripheral deficit on the left, the vertigo remained
absent.
Over the course of 3 years, the patient’s speech discrimination score fell to 0% in the left ear despite the absence of
tumor regrowth on imaging studies. Electrocochleography
showed an increase in the SP/AP ratio in both ears (right:
0.48; left: 0.53), and she began noticing a fluctuation in
the hearing in her right ear and a return of the vertigo.
There was also a subtle increase in the size of her rightsided endolymphatic sac tumor. She elected to continue
medical management.
A noteworthy aspect of this case is that it was included
in an earlier series describing hearing preservation surgery
in von Hippel-Lindau disease–related endolymphatic sac
tumors.8 Since that report was written, new electrocochleographic data presented herein further support the hypothesis
that the affected ears are indeed hydropic.
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CMEJREK, MEGERIAN
Discussion
The role of endolymphatic hydrops in Ménière’s disease
has been a topic of much discussion in the otolaryngology literature since it was first described by Hallpike and
Cairns in 1938.9 To date, the most reliable animal model
of hydrops has been the guinea pig, the model initially
described by Kimura and Schuknecht.10 However, studies
of endolymphatic duct obstruction in primates have not as
strongly supported its role as a principal inciting pathologic
entity in Ménière’s disease in humans.11,12 The limitations
of detecting hydrops in living patients has made it difficult
to definitively establish a cause-and-effect relationship
between endolymphatic obstruction, Ménière’s disease,
and its proposed histopathologic correlate, endolymphatic
hydrops.
Our findings, combined with those of Jahrsdoerfer et al6
and Hosseinzadeh et al,7 support the concept that obstruction
of the endolymphatic sac and duct by a number of causes
(e.g., a tumor, vascular anomaly, or internal sac disease)
can produce symptomatic Ménière’s-like disease, likely
via the production of endolymphatic hydrops, as has been
seen in the guinea pig.10 This concept is supported by the
presence of the electrocochleographic abnormalities in 2
of our patients and the relief of their vertigo symptoms by
surgical decompression or VIIIth nerve section.
Our findings and those of temporal bone histologic studies support the concept that even microscopic violation of
the endolymphatic duct can potentially incite hydrops.13,14
Yoon et al were able to show that endolymphatic hydrops
and otosclerotic obstruction of the vestibular aqueduct can
coexist.13 Rizvi and Gibbin demonstrated that vestibular
aqueduct obstruction secondary to fracture-induced ossification also has the potential to produce hydrops.14
These findings support the concept that any disturbance
of longitudinal outflow of endolymph can lead to the
development of endolymphatic hydrops and Ménière’s
symptomatology.
The cause of idiopathic Ménière’s disease in the absence
of obvious endolymphatic sac or duct obstruction remains
unclear. Data on the underabsorption or overproduction of
endolymphatic fluid are still being accumulated. Clinical
data presented in our report and others6,7,10 indicate that
sac and duct malfunction by reason of gross obstruction
appears to be an important contributing cause of hydrops
production in some cases. Hence, the evidence indicates
that a variety of lesions that cause obstruction of the endolymphatic sac by external or internal luminal obstruction
can lead to clinical Ménière’s disease symptomatology.
Our 3 case reports provide further evidence to support the
idea that endolymphatic hydrops represents the final common pathway in the production of Ménière’s symptomatology. However, they also underscore the fact that Ménière’s
disease is a diagnosis of exclusion. Careful physical and
radiologic assessment of each patient is warranted even
756
when classic Ménière’s disease seems to be the most likely
diagnosis. Further research into the underlying mechanisms
of endolymphatic hydrops will likely lead to refinement
of our current understanding of the link between hydrops
and Ménière’s disease in the coming years.
References
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and evaluation of therapy in Meniere’s disease. American Academy
of Otolaryngology–Head and Neck Foundation, Inc. Otolaryngol
Head Neck Surg 1995;113:181-5.
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a target antigen of anti-inner ear antibodies in autoimmune inner
ear diseases. Otol Neurotol 2001;22:614-18.
3. Takahash K, Aono T, Shichinohe M, et al. Herpesvirus DNA in
peripheral blood mononuclear cells of some patients with Meniere’s
disease. Microbiol Immunol 2001;45:635-8.
4. Noell CA, Roland PS, Mabry RL, Shoup AG. Inhalant allergy and
Meniere’s disease. Use of electrocochleography and intranasal allergen challenge as investigational tools. Otolaryngol Head Neck
Surg 2001;125:346-50.
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Laryngol 1981;90(6 Pt 1):619-23.
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disease caused by an anomalous vein of the vestibular aqueduct.
Arch Otolaryngol Head Neck Surg 1998;124:695-8.
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Hippel-Lindau syndrome. Otol Neurotol 2002;23:378-87.
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syndrome. J Laryngol Otol 1938;53:625-55.
10. Kimura RS, Schuknecht HF. Membranous hydrops in the inner ear
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endolymphatic sac in a primate species. Laryngoscope 1988;98:
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