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Operative management of external auditory canal
cholesteatoma: case series and literature review
M SAYLES, H A KAMEL, F F FAHMY
Department of Otorhinolaryngology - Head and Neck Surgery, West Suffolk Hospital NHS Trust, Bury
St. Edmunds, UK
Abstract
Objectives: To describe the clinical features of external auditory canal cholesteatoma, and to assess the outcome
following bony meatoplasty with tragal cartilage and perichondrium graft repair.
Methods: A retrospective review was carried out, comprising all patients with external auditory canal
cholesteatoma who presented between January 2007 and December 2011. Patients underwent pre-operative
audiometry and computed tomography imaging of the temporal bones, before undergoing bony meatoplasty via
a postauricular incision. Pre- and post-operative comparisons were made of patients’ otological symptoms and
the otoscopic appearance of the external ear canal.
Results and conclusion: Eight patients were included in the analyses. The median age of patients was 46.5 years
(range 14– 68 years), with a male to female ratio of 1:1. The median length of follow up was 16 months. The most
common presenting features were unilateral otalgia and purulent otorrhoea. All patients had relatively advanced
disease at presentation, with erosion of the temporal bone. All patients underwent bony meatoplasty via a
postauricular approach to eradicate the diseas e. Bony meatoplasty was successful in the definitive management
of external ear canal cholesteatoma.
Key words: Cholesteatoma; External Auditory Canal; Otologic Surgical Procedures
Introduction
External auditory canal cholesteatoma is a rare disease
entity with an uncertain aetiology. Few case series have
been reported in the literature, and current management
is highly variable between centres. The locally erosive
and indolent nature of cholesteatoma in the bony exter-
nal ear canal gives rise to complications resulting from
erosion into adjacent structures, such as the mastoid
and the temporomandibular joint.
This study aimed to describe the clinical features of a
series of patients treated for cholesteatoma of the exter-
nal ear canal. We report our experience of operative
management in these patients, who underwent bony
meatoplasty.
Materials and methods
The majority of patients in the series reviewed were
referred to otolaryngology by their general practitioner
with a history of unilateral otalgia and otorrhoea, for
which they had received an (often unsuccessful) trial
of conservative antimicrobial medical therapy prior to
referral. Otoscopy most frequently showed erosion of
the inferior aspect of the bony canal wall, with accumu-
lated keratin and bony sequestrum. A clinical diagnosis
of external auditory canal cholesteatoma was made on
the basis of these findings.
Each patient underwent pre-operative investigation
with high-resolution computed tomography (CT) of
the temporal bones, audiometric assessment, and exam-
ination under anaesthesia with biopsy of the ear canal
lesion where necessary. Axial CT with coronal recon-
struction was used to assess the extent of local involve-
ment. These imaging studies confirmed the presence of
bony canal wall erosion, with or without overlying soft-
tissue attenuation material. Examination of the external
auditory canal lesion under anaesthesia, and biopsy
where appropriate, was used to exclude malignant
(necrotising) otitis externa and squamous cell carci-
noma of the external auditory canal skin. Histological
analysis of biopsy specimens showed keratin, with no
evidence of squamous malignancy.
In each case, the disease was at a relatively advanced
stage, with erosion of the temporal bone. All cases were
managed surgically in order to eradicate the disease
process, preserve normal structure and function, and
provide patients with a self-cleaning ear canal. Bony
meatoplasty, carried out via a postauricular approach,
was performed under general anaesthesia in a main
operating theatre. The postauricular and ear canal skin
Accepted for publication 23 January 2013 First published online 20 August 2013
The Journal of Laryngology & Otology (2013), 127, 859– 866.
MAIN ARTICLE
© JLO (1984) Limited, 2013
doi:10.1017/S0022215113001850
was first infiltrated with 4 ml of 2 per cent lidocaine
hydrochloride with adrenaline (1:80 000). The ear
canal re-entry incision was made just lateral to the cho-
lesteatoma sac. The cholesteatoma sac was elevated and
the cholesteatoma was excised. In order to provide a
smooth ear canal contour, the bony irregularities and
the edge of the bony erosion were drilled out. The
resulting cavity was obliterated with tragal cartilage
and perichondrium grafts, with or without temporalis
fascia, to achieve a smooth, self-cleaning ear canal.
The postauricular wound was closed using layers of
subcutaneous vicryl with subcuticular Monocryl
sutures (Ethicon, Somerville, New Jersey, USA). The
ear canal was then packed with two small pieces of
ribbon gauze (approximately 2 cm in length) impreg-
nated with bismuth iodoform paraffin paste (BIPP). A
simple dry gauze dressing was applied to the ear.
Patients were reviewed and, if well, discharged home
on day one following surgery.
Follow up in the out-patient otolaryngology clinic
was arranged two weeks post-surgery for removal of
the BIPP packing. At this stage, patients were given a
one-week course of Sofradex ear drops (Sanofi-
Aventis, Guildford, UK). Patients were reviewed
again at six weeks post-surgery. Thereafter, patients
were kept under regular follow up (usually with six-
monthly intervals). The post-operative follow-up
period for this case series ranged from 6 to 36
months (median 20.5 months).
Results
Eight cases of external auditory canal cholesteatoma
were identified within the study period (Table I). The
median age of patients at presentation was 46.5 years
(range 14– 68 years), and the male to female ratio was
1:1. The most common presenting features were non-
specific unilateral otalgia and purulent otorrhoea. All
patients had relatively advanced disease at presentation,
with erosion of the temporal bone (Table II). The
patients underwent bony meatoplasty via a postauricular
approach in order to eradicate the disease process. One
patient developed a second lesion post-operatively. The
median follow-up period was 16 months. Three selected
cases are described in detail below, with exemplar CT
images and intra-operative photographs.
Case one
A 68-year-old man was referred by his general prac-
titioner with a two-year history of recurrent right-
sided otitis externa. He was a smoker, with a
background of chronic obstructive pulmonary disease,
hypertension, and ischaemic heart disease with pre-
vious coronary artery bypass grafting. The otitis
externa had been managed intermittently with topical
antibiotics prescribed by his general practitioner. On
attending the senior house officers’ emergency otolar-
yngology clinic, the patient described right-sided
otalgia and a sense of aural fullness, with associated
purulent otorrhoea. Medical management with topical
and systemic antibiotics, in combination with aural
toilet, was unsuccessful. He was therefore referred for
a senior specialist opinion.
Otoscopy revealed two ar eas of erosion in the inferior
aspect of the ear canal, which contained bony sequestr a.
Computed tomography confirmed the pr esence of abnor-
mal soft tissue and erosion of the external auditory canal
floor (Figur e 1a). The appearance of the middle-ear cleft
on CT scans was normal. Audiometric assessment
showed moderate to severe high-frequency sensorineural
TABLE I
SUMMARY OF RESULTS
Pt sex, age
(y)
Presenting features Aetiology Risk
factors
Stage
8
Treatment
M, 68 Otalgia, purulent otorrhoea Idiopathic Smoker III Bony meatoplasty
M, 14 Otalgia, purulent otorrhoea Idiopathic – III Bony meatoplasty
F, 46 Otalgia, bloody otorrhoea Idiopathic Diabetic III Bony meatoplasty, topical antibiotics for 2nd
lesion
F, 60 Otalgia, aural fullness,
progressive hearing loss
Idiopathic Smoker III Topical antibiotics, regular aural toilet, bony
meatoplasty at 3 y
F, 37 Otalgia, purulent otorrhoea Idiopathic Smoker III Bony meatoplasty
M, 58 GP referral for aural toilet for wax Idiopathic Hearing
aids
III Bony meatoplasty
M, 39 Otorrhoea Idiopathic Smoker IV (mastoid) Bony meatoplasty
F, 47 Otalgia, purulent otorrhoea Idiopathic – III Bony meatoplasty
Pt = patient; y = years; M = male; F = female; GP = general practitioner
TABLE II
EXTERNAL AUDITORY CANAL CHOLESTEATOMA
STAGING CRITERIA
Stage Histologic
criteria
Macroscopic criteria
I Epithelial
hyperplasia
–
IIa/b Periosteitis Hyperplasia with erythema (IIa), or
denuded but not eroded bone (IIb)
III – Canal wall erosion & bony
sequestration
IV – Invasion into adjacent structures
∗
∗
Subclasses of disease stage IV include: mastoid (M), skull base
and sigmoid sinus (S), temporomandibular joint (J), and facial
nerve canal (F).
M SAYLES, H A KAMEL, F F FAHMY860
hearing loss bilaterally. Examination under general
anaesthesia revealed a 3 mm defect filled with cholestea-
toma, with no involvement of the middle ear. There were
no suspicious areas; hence biopsy was not carried out.
Bony meatoplasty was performed through a post-
auricular approach, with an ear canal skin incision
just lateral to the cholesteatoma pocket. Henle’s spine
was drilled out, the cholesteatoma pocket was elevated,
and the bony irregularities and ridge were drilled to
smooth the cavity. The cholesteatoma cavity was
obliterated with a tragal cartilage and perichondrium
graft (Figure 1b–e). The canal floor was well healed
at the six-week follow up. He remained well six
months later.
Case two
A 14-year-old boy was referred by his general prac-
titioner with an 8-week history of right-sided otalgia
and purulent otorrhoea, which was unresponsive to
topical and systemic antimicrobial therapy. Initial
FIG. 1
Case one: (a) coronal computed tomography scan, showing soft-tissue attenuation material overlying bony erosion in the right external auditory
canal floor (arrow) and normal bony appearances on the left (asterisk); (b) otoscopic appearance of ear canal cholesteatoma; and intra-operative
photographs, showing (c) cholesteatoma excised and bony irregularities drilled out, (d) cartilage graft in situ, and (e) perichondrium in situ.
EXTERNAL AUDITORY CANAL CHOLESTEATOMA MANAGEMENT 861
examination in the senior house officers’ emergency
otolaryngology clinic showed a large aural granulation
tissue polyp. After aural microsuction, the patient
was given a course of Gentisone HC ear drops
(Amdipharm, Basildon, UK) and followed up one
week later. At his next clinic appointment, the polyp
had receded and was cauterised with silver nitrate.
One week later, he was found to have an underlying
keratin-filled erosion of the inferior wall of the right
ear canal (Figure 2b, c).
Computed tomography revealed bony erosion of the
inferior wall of the right external ear canal, with normal
appearances of the middle ear (Figure 2a). Audiometric
assessment showed normal hearing bilaterally. The
patient subsequently underwent bony meatoplasty. At
surgery, he was found to have two cholesteatoma
FIG. 2
Case two: (a) coronal computed tomography scan, showing bony erosion of the right external auditory canal floor (asterisk); (b) and (c) oto-
scopic appearances of the cholesteatoma eroding the external auditory canal wall; and intra-operative photographs showing (d) the middle ear
clear of disease, with the chorda tympani intact, and (e) cartilage palisade grafts in situ.
M SAYLES, H A KAMEL, F F FAHMY862
pockets adjacent to the tympanomastoid suture line,
with no extension into the middle ear. The cholestea-
toma was removed and the defects were filled with car-
tilage palisade grafts (Figure 2d, e).
Case three
A 46-year-old woman presented with a 6-month history
of intermittent right-sided otalgia and otorrhoea. She
had been treated with oral amoxicillin for otitis
externa on two occasions over the preceding four
months, as prescribed by her general practitioner. The
patient had a background of treated hypertension. In
addition, she had well controlled type II diabetes mel-
litus and was on oral hypoglycaemic medication; her
most recent HbA1c had been reported as being 7.9
per cent. She was a non-smoker.
Initial assessment revealed erosion of the floor of the
right external auditory canal, with an accumulation of
keratin debris. Following aural toilet, tri-adcortyl oint-
ment was applied to the erosion. Audiometric assess-
ment showed a high-frequency sensorineural hearing
loss bilaterally. Computed tomography confirmed the
superficial erosion of the floor of the right ear canal,
which involved the temporal bone inferiorly and pos-
teriorly (Figure 3a).
Biopsy of the ear canal lesion was carried out under
general anaesthesia to rule out malignant (necrotising)
otitis externa and squamous cell carcinoma of the
FIG. 3
Case three: (a) coronal computed tomography (CT) scan, showing soft-tissue attenuation mass in the right ear canal, with underlying erosion of
the adjacent temporal bone (arrow); intra-operative photographs demonstrating (b) abnormal bony prominence and cholesteatoma in ear canal,
and (c) a clear middle ear; and (d) coronal CT scan, showing erosion of the adjacent temporal bone anteroinferiorly (arrow) and bony erosion
adjacent to the scutum superiorly (asterisk).
EXTERNAL AUDITORY CANAL CHOLESTEATOMA MANAGEMENT 863
external auditory canal skin. Histological analysis of
the tissue specimen showed no evidence of malig-
nancy, and was consistent with a diagnosis of external
auditory canal cholesteatoma. The patient subsequently
underwent right-sided bony meatoplasty and tympanot-
omy to exclude any middle-ear disease. At surgery, the
middle ear was found to be free from cholesteatoma
(Figure 3b, c). Bony meatoplasty was carried out
with tragal cartilage and a perichondrium graft to the
external auditory canal wall.
At follow up, the external auditory canal was
initially well healed. However, one year following
surgery the patient was referred back to the otolaryn-
gology clinic by her general practitioner with increas-
ing right-sided otalgia and otorrhoea. She was
diagnosed with eczematous otitis externa. After a
further six months, examination by the senior author
revealed a small area of cavitation in the external audi-
tory canal posterosuperiorly, which contained bony
sequestrum. This was in a different location to her pre-
vious disease. Computed tomography was repeated.
This showed thickening of the ear canal soft tissues,
with bony destruction adjacent to the scutum super-
iorly. Anteriorly, there was involvement of temporal
bone at the level of the temporomandibular joint
(Figure 3d).
The patient was treated initially with oral ciproflox-
acin and topical ofloxacin ear drops. Two months
later, the ear canal lesion was found to be healing
well. She was still under regular follow up at the time
of writing.
Discussion
Aetiology
Cholesteatoma is most commonly found in the middle-
ear cavity. Rarely, cholesteatoma occurs in the external
auditory canal, with an estimated incidence rate of
1.2– 3.7 per 1000 new otology patients.
1,2
The annual
incidence rate of external auditory canal cholesteatoma
in the general population is 0.15 cases per 100 000 indi-
viduals,
2
compared with 9.2 cases per 100 000 individ-
uals per year for middle-ear cholesteatoma.
3
The aetiology of external auditory canal cholestea-
toma remains unclear.
4,5
Idiopathic external auditory
canal cholesteatoma is distinguished from cholestea-
toma that arises secondary to a previous ear canal
insult. Many authorities believe that idiopathic external
auditory canal cholesteatoma results from a reduced
migratory capacity of the canal epithelium, which
leads to ‘keratinisation in situ’.
2,6– 8
However, this
view has recently been challenged by a study which
showed no difference in the rate of epithelial migration
between normal ears and those affected by external
auditory canal cholesteatoma.
9
In some cases, the
occurrence of external auditory canal cholesteatoma
has been linked to branchial arch anomalies, which
result in the retention of epithelial masses and lead to
cholesteatoma formation in the external auditory
canal floor.
4,10
Epidemiologically-linked risk factors for the devel-
opment of external auditory canal cholesteatoma
include smoking, diabetes mellitus and repeated micro-
trauma (e.g. from cotton buds or hearing aids).
4,5
Smoking and diabetes are thought to result in microan-
giopathic changes in the ear canal that potentially
impair epithelial migration.
5
The majority of idiopathic
external auditory canal cholesteatoma occur in the
inferior canal wall. This is thought to be due to the rela-
tively poor blood supply to the skin along the inferior
aspect of the canal.
None of the cases presented here had any identifiable
aetiological factor; at best, they can be regarded as idio-
pathic external auditory canal cholesteatoma (Table I).
Four of the patients were smokers, one patient was dia-
betic, and one wore hearing aids; the use of hearing
aids may have predisposed the individual to external
auditory canal cholesteatoma through repeated micro-
trauma to the ear canal skin.
Presenting features
A recent meta-analysis of published case series con-
cluded that the most common presenting symptoms
of idiopathic external auditory canal cholesteatoma
are unilateral otorrhoea with mild to moderate
otalgia.
5
A minority of patients complained of unilat-
eral hearing loss; or were asymptomatic, with the cho-
lesteatoma being discovered on routine otoscopy
performed for a separate indication. These findings
are consistent with our experience. Six of the eight
patients presented with unilateral otalgia, five of
which presented with associated otorrhoea. One
patient had painless otorrhoea; one patient mentioned
progressive unilateral hearing loss; and one was asymp-
tomatic, with cholesteatoma being discovered inciden-
tally on otoscopy.
Staging and complications
The indolent and locally erosive nature of external
auditory canal cholesteatoma can result in late presen-
tation, with severe complications due to the involve-
ment of neighbouring structures. If the cholesteatoma
invades into the mastoid, it may erode the facial
nerve canal, sigmoid sinus and semicircular
canals.
2,7,11– 17
Erosion through the anterior wall of
the canal may affect the temporomandibular
joint.
2,13,18
Rarely, in advanced cases, extension into
the posterior fossa has been reported, with resulting
intracranial abscess.
15
Naim et al.
8
developed a (I– IV) staging system for
external auditory canal cholesteatoma based on the
extent of erosion into nearby structures (Table II).
Seven of the cases reported here presented with stage
III disease, in which there was erosion of the adjacent
temporal bone in the inferior aspect of the external
auditory canal. In one patient, the disease involved
the adjacent mastoid air cells and was therefore
M SAYLES, H A KAMEL, F F FAHMY864
graded as stage IV (mastoid subclass).
8
The majority of
cases reported in the literature are of at least stage IIb.
Reports of stage I external auditory canal cholestea-
toma are very rare.
5,8
This is probably because the ear-
liest stages of the disease are usually asymptomatic. As
the disease progresses to involve the bony canal walls,
the accumulated keratin debris and bony sequestrum
become a focus for infection, which results in the
typical presentation with recurrent otalgia and
otorrhoea.
Computed tomography of the temporal bones has
become accepted as the gold standard for staging and
pre-operative planning in external auditory canal cho-
lesteatoma.
19
This method allows accurate evaluation
of the extent of local bone erosion and examination
for the involvement of adjacent structures.
Treatment
As with middle-ear cholesteatoma, the aims of treatment
in e xternal auditory canal cholestea toma cases are the
eradication of the disease with pr eservation of normal
structure and function, and the restoration of normal epi-
thelial migra tion. C onservative therapy, with fr equent
debridement of the keratin debris and sequestered
bone, is fa v oured in early stage disease.
5,11
If these
simple measures are inadequate to control otalgia and
otorrhoea, or in more advanced disease (stages
IIb–IV), surgical intervention is necessary. The aim of
surgery is to excise the cholesteatoma and to restore a
smooth, self-cleaning canal wall epithelium, usually
with the aid of cartilage and fascial grafts to pr otect
denuded structures, and fill any canal wall defect.
When the mastoid air cells are invaded, a modified
radical mastoidectomy may be indicated, with the tym-
panic membrane and ossicles left intact.
20
• External auditory canal cholesteatoma is rare,
with potentially serious complications
• Computed tomography is the investigation of
choice for disease staging and pre-operative
planning
• Most patients present with non-specific
symptoms of unilateral otalgia and otorrhoea
• Bony meatoplasty with cartilage graft repair
is effective in the definitive management of
this disease
All our patients underwent bony meatoplasty via a
postauricular approach. One patient was initially reluc-
tant to pursue operative management as her symptoms
were mild. She was therefore initially managed with
topical antibiotic preparations and regular debridement
in the clinic. After three years of follow up, she under-
went successful curative surgery. One patient suffered
further external auditory canal cholesteatoma at a sep-
arate location in the same ear canal 18 months after
bony meatoplasty. This was being managed conserva-
tively at the time of writing.
Conclusion
External auditory canal cholesteatoma is a poorly
understood and rare disease entity, which presents
diagnostic and therapeutic challenges. Computed tom-
ography is the most useful investigation for disease
staging and pre-operative planning. Of the eight
patients reviewed, seven underwent meatoplasty for
stage III external auditory canal cholesteatoma and
one for stage IV (mastoid subclass) disease. In the
absence of surgical intervention, close clinical monitor-
ing with regular follow up is required to treat symptoms
and monitor patients for potentially serious
complications.
Acknowledgement
We would like to thank Mr Patrick Axon (consultant ENT
surgeon at Addenbrooke’s Hospital, Cambridge, UK) for
his assistance in the management of case seven.
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Address for correspondence:
Mr M Sayles,
Department of Otorhinolaryngology - Head and Neck Surgery,
West Suffolk Hospital NHS Trust,
Hardwick Lane,
Bury St. Edmunds IP33 2QZ, UK
E-mail: sayles.m@gmail.com
Mr M Sayles takes responsibility for the integrity
of the content of the paper
Competing interests: None declared
M SAYLES, H A KAMEL, F F FAHMY866
