This document discusses congenital malformations of the external ear. It begins with applied anatomy of the normal ear and embryology of ear development. It then describes various congenital deformities that can occur, including pre-auricular tags, prominent ears, cryptotia, microtia, and congenital aural atresia. For treatment, options include observation, prosthetics, reconstruction with rib cartilage grafts, and surgical correction of atresia. Reconstruction is often done in multiple stages to form the shape of the pinna.

1. CONGENITAL MALFORMATIONS
OF EXTERNAL EAR
By Dr. Yousuf F. Choudhury
PGT, ENT Dept
Moderated By
Dr. Shams Uddin
Prof. HOD, ENT Dept.
Silchar Medical College

2. APPLIED ANATOMY

4. • Average adult female ear is 59 mm tall and the
average male is 63mm tall.
• 85 % of height of ear is achieved by 3 years of
age and almost 100% by 10 years of age.
• The size of ear remains the same size till the
age of 60 when it gradually enlarges
particularly the lobe.
• The average adult ear protrudes 19 mm from
the mastoid skin

5. • The long axis of the ear slopes backwards in
line with the slope of the nose.
• The ear lies between the level of the eyebrow
and a line of few millimetres beneath the
nasal columella.
• The distance between the lateral canthus of
the eye to the front of the ear is just over the
length of the ear.

6. EMBRYOLOGY OF EAR

7. • During the sixty week of intrauterine life the
external ear begins to develop around the dorsal
end of the first branchial cleft. On either side of
this cleft lie the first (mandibular) and second
(hyoid) arches.
• The auricle develops from these arches as 6 small
buds of mesenchyme known as the six hillocks of
His.
• The first arch gives rise to the hillocks 1 to 3 and
the second arch gives rise to hillocks 4 to 6.

8. • There has been always a
controversy regarding
formation of which part of
ear from which hillock.
• The auricle begins to
develop in the anterior neck
region, then it is postulated
to migrate dorsally and
cephalad as the mandible
begins to develop during
the second and third
months of gestation. By the
5th month of gestation the
pinna lies in its adult
location.
HILLOCKS PART OF PINNA
1 ANTERIOR PORTION
OF EAR LOBE
2 TRAGUS
3 ASCENDING HELIX
4 ANTI-HELIX
5 HELIX
6 POSTERIOR
PORTION OF LOBE.

9. • The external auditory canal begins to develop from
the first branchial cleft during the first two months of
gestation.
• During the first month a solid epithelial cell rest
forms in this area and is in contact with the
endoderm of the first pharyngeal pouch. There is an
intervening mesoderm preventing direct contact
between the ectoderm and endoderm

10. CONGENITAL DEFORMITIES OF
EXTERNAL EAR

11. PRE-AURICULAR TAGS
• Very common
• Involves only skin but
usually contains a long
tail of cartilage
extending into the
cheek.
• Liga clip – tag drops off
• Vertical elliptical
excision

12. MIRROR EAR OR POLYOTIA
• Persistent pre-auricular
tissues lying on posterior
cheek resembling extra
ear.
• Skin is peeled off the
extra-auricular tissue,
cartilage remnants
trimmed & packed into
anterior conchal hollow.
Skin redraped to give
cheek flatter shape

13. PRE-AURICULAR PITS
AND SINUSES
• Often bilateral &
frequently
asymptomatic.
• Track deeply to facial
nerve.
• Excision with facial
nerve monitoring.

14. ABNORMAL FOLDS OF PINNA
• Common
• Lop ear - Upper pole of the ear flops over
• ‘Mustarde’ type suture used to create U-shaped
cartilage prop at missing upper anti-helical fold. Ear
hitched to the mastoid fascia
• Other varieties are –
Kink of helical rim
 Abnormal fusion of helical rim to the anti-helical fold
Whole ear appears collapsed vertically
• Surgical correction by scoring, tie-bar type
tethering sutures or direct wedge excision

16. PROMINENT (‘BAT’) EARS
• Prominence is due to an
absent anti-helical fold but in
some cases, the conchal bowl
is excessively deep
• Grading by Graham and Gault.
• Digital pressure on relevant
part of ear determines cause
and gauge strength of
cartilage.
• Recommended to do surgery
only after 5 years of age.
• Surgical techniques – anterior
scoring, reshaping of the
curves by the use of posterior
sutures and excision
techniques to set back the
concha.
• Very challenging surgery

17. COLLAPSED EARS
• Scaphal hollow folded backwards to rest on conchal
hollow.
• Surgical reconstruction by releasing the soft tissue
tethering between scaphal and conchal cartilages and
splinting these structures apart with a cartilage graft (
conchal hollow)
FOLDED OVER HELICAL RIM
– Helical rim sharply folded over providing double layered in
a single skin envelope, ear looks pinched.
– Folded over cartilage excised and then repositioned.
– Noonan Syndrome
BUMPS
– Bump on helical rim
– Common
– Hillocks 3 & 4 irregular fuison

18. AURICULAR CLEFTS
– Groove or notch due to
poor fusion of hillocks 6 &
1
– In few, significant portion
of lobe mission due to
absence of hillock 6.
– Re-alignment of deep
tissues with deep suture.
UNDERDEVELOPED OR
ABSENT LOBE
– Rebuilt around cartilage
framework using conchal
cartilage.

19. MACROTIA
• Excessively large ears.
• In normal ear, upper pole,
conchal hollow and lobe
take up an equal amount
of the height of ear,
splitting in to thirds.
• Big scaphal hollow or big
lobe are the reasons of
macrotia.
• Anterior crescent of skin
and cartilage be removed
from scaphal hollow.
• Wedge of tissue is
removed from oversized
lobe

20. CUP EARS
• Helical rim is constricted to give prominent,
cone shaped ear.
• Difficult to correct.
• Several techniques used that include V-Y
plasty, recnstruction using carved costal
cartilage.

21. CRYPTOTIA ( ‘THE HIDDEN EAR’ )
• Lower two thirds of ear visible,
upper auricular sulcus seems
lost.
• When ear is pulled away from
the side of the head, the upper
pole cartilage becomes evident,
having hidden beneath scalp
skin.
• Upper pole is tethered and
lower lobe is prominent.
• Small ear buddies splint applied
at birth for non-surgical
correction. Later surgical
correction by releasing the
tethered portion of ear.

22. MICROTIA & CONGENITAL AURAL ATRESIA

23. DEFINITION
• Microtia:
Defined as the abnormal development of the Pinna
resulting in a malformed auricle.
• Congenital aural atresia:
Defined as a failure of development of external
auditory canal.
Congenital aural atresia is always associated with
a certain degree of microtia.

24. EPIDEMIOLOGY
• Microtia and congential auditory atresia occur in
approximately 1 in every 6000 live births.
• These deformities commonly occur unilaterally, more so on
the right side.
• Men are affected thrice as common as women. The degree
of auricular deformity usually correlates with the degree of
middle ear deformity.
• The incidence of inner ear deformities are very rare in
patients with congenital auditory atresia.
• Microtia is associated with other anomalies of face 50% of
the time.
• Women with four or more pregnancies are at increased risk
of bearing a child with microtia.
• The incidence of microtia is higher in Japanese population.

25. ETIOLOGY
• Exposure to teratogens like vitamin A, thalidomide, isotretinoin
• Vascular insults and genetic aberrations.
• Isolated microtia can occur with branchial arch anomalies.
• Syndromic associations of with congenital aural atresia include
– Goldenhar syndrome,
– mandibular facial dysostosis,
– brachio-otorenal syndrome
– Hemifacial microsomia
– Sticklers syndrome
– Crouzons syndrome
– Noonan syndrome
– Foetal Alcohol Syndrome
– CHARGE

26. PATHOGENESIS
CONGENITAL AURAL ATRESIA
• At 28 weeks, a core of ectoderm canalizes from medial to
lateral and eventually breaks through to communicate with
the conchal depression.
• Failure of canalization or more rarely lack of ectodermal
migration can lead to atresia of the external auditory
meatus (EAM) and partial canalization leads to meatal
stenosis (an EAM with a diameter of less than 4 mm).
• Disruption of normal canalization or ectodermal migration
can lead to arrested development of the tympanic ring
mesoderm with the formation of a dense atretic bony plate
in place of the tympanic membrane, an almost universal
finding in canal atresia.

27. MICROTIA
• Malformation, such as anotia and microtia,
are likely to be caused by the disturbance of
development at seven to eight weeks
gestational age, whereas deformations (lop,
cup and prominent ears) are caused by a
problem later in the development or by
external compression.

28. CLASSIFICATION
• Marx ‘s classification of external ear has proposed
four descriptive groups which was later amended
by Aguilar and Jahrsdoefer enabling the surgeon
to categorize auricular deformity easily and into
three grades.
• Altman gave anatomical classification of
congenital aural atresia which was later modified
by Marquet and Cremers.
• De la Cruz classification of congenital aural atresia
based on HRCT scan is also used frequently by
some surgeons.

29. GRADING OF MICROTIA ( MARX )
Slightly small or
malformed ear.
Often there is no
surgery required
since the
malformation is
mild
GRADE I MICROTIA
An ear with
structural
deficiencies such as
absent scapha,
absent lobule,
broadened helical
rim, missing helix
etc
GRADE II MICROTIA
Severe auricular
deformity with the
no recognizable
structures present,
anotia
GRADE III MICROTIA

30. CLASSIFICATION OF AURAL ATRESIA
GROUP DESCRIPTION
Grade I TM hypoplastic. Tympanic bone is normal
or hypoplastic. Ossicular malformation
present but stapes is usually mobile
Grade II Atretic plate present. Typanic bone is
normal or hypoplastic. Tympanic cavity
within normal limits. (In Marquet’s
modification, Course of facial nerve is
normal in sub-type ‘a’ and is abnormal in
sub-type ‘b’. In Cremer’s modification,
there is partial bony atresia in sub-type ‘a’
and total bony atresia in subt-type ‘b’)
Grade III Above abnormalities may be found with a
severely hypoplastic tympanic cavity.

31. DE LA CRUZ CLASSIFICATION
HRCT based
• Mastoid Pneumatization
• Inner ear normality
• Facial nerve
• Footplate

32. DE LA CRUZ CLASSIFICATION
Minor
Malformations
• Normal mastoid
pneumatization
• Normal oval
window/footplate
• Good facial nerve–
footplate
relationship
• Normal inner ear

33. DE LA CRUZ CLASSIFICATION
Major
Malformations
• Poor
pneumatization
• Abnormal or absent
oval
window/footplate
• Abnormal course of
facial nerve
• Abnormalities of
inner ear

34. MANAGEMENT
Investigations :
 Age appropriate Hearing assessment
 HRCT Temporal bones
X-ray Cervical spine
USG for congenital renal malformations
Panorex for malocclusion

35. Type Details Advantages Disadvantages
Observation No Risk Appearance
Prosthetic Adhesive retained Appearance Less secure attachment
Ongoing prosthetic care
Daily maintenance Use
restrictions
Implant retained Appearance
Secure retention
Multiple procedures
Requires removal of remnant
and soft tissue Ongoing
prosthetic care Daily
maintenance Use restrictions
Reconstruction Rib Cartilage
(Autogenous)
Autogenous tissue
Minimal maintenance
Becomes sensate
Atresia repair
Inconsistent appearance
Donor sites Multiple
surgeries Reconstruction
performed between 6 and
10 years of age
Medpor Less donor site
morbidity Less
variability in carving
Reconstruction
performed at earlier
age
Foreign body
More challenging to
integrate with atresia repair
OPTIONS FOR MICROTIA MANAGEMENT

36. MICROTIA RECONSTRUCTION WITH
AUTOGENOUS CARTILAGE
• The technique was refined by Tanzer, father of Otoplasty.
• Tanzer surgery: Performed in four stages. There is a three
month gap between these stages.
First stage: Rib cartilage is harvested and sculptured into
the shape of pinna and is placed under skin pocket of the
microtic ear.
Second stage: Formation of the lobule
Third stage: Elevation of the ear with insertion of a post
auricular skin graft
Fourth stage: Formation of the tragus with a skin/cartilage
composite graft from the contralateral ear and full-
thickness skin graft for the conchal area from the
contralateral ear

37. • Nagata technique: This is a two staged procedure
developed by Nagata. This involves constructing the
auricular framework form the sixth to ninth rib
cartilages. The framework is created using stainless
steel sutures. There is six months gap between the
two stages.
– Stage 1: Cartilage Implantation and Lobule
Transposition
– Stage 2: Elevation of the Ear and Creation of Post-
auricular Sulcus

38. COMPLICATIONS OF MICROTIA SURGERY
• MAJOR
– hematoma formation, skin flap necrosis, infection,
and pneumothorax.
• MINOR
– malpositioning, scar contracture or hypertrophy,
and poor contour.

39. MANAGEMENT OF CONGENITAL AURAL ATRESIA
• When associated with microtia, congenital aural atresia
reconstruction may be undertaken before microtia
reconstruction, after completion of all stages, or in
combination with a stage of microtia repair.
• Historically, most authors advocate CAA repair to follow
three stages of microtia reconstruction: cartilaginous
auricular reconstruction, lobule rotation, and postauricular
elevation and skin grafting.
• Currently, the optimal age to begin auricular reconstruction
is generally considered age 7 years.
• For the occasional case of CAA without microtia and for
CEACS, the atresiaplasty may be undertaken after the age
of 4 years.

40. • Jahrsdoefer et al. proposed a scoring system
for the selection of patients with congenital
aural atresia using a ten-point scale based on
CT-scan elements and the appearences of
external ear.
• Score 8-10 achieved post-operative SRT of 5-
25 dB.

41. SCORING SYSTEM FOR CANDIDACY FOR SURGERY FOR
CONGENITAL AURAL ATRESIA
SCORE
Stapes present 2
Oval window open 1
Middle ear space 1
Facial nerve 1
Malleus incus complex 1
Mastoid Pneumatization 1
Incus stapes connection 1
Round window 1
Appearance of external ear 1
Total availabl points 10

42. Prognostic Rating Scale
• 10 Excellent
• 9 Very good
• 8 Good
• 7 Fair
• 6 Marginal
• ≤5 Poor
de Alarcon A, Jahrsdoerfer RA, Kesser BW. Congenital absence of the oval window: diagnosis, surgery, and audiometric outcomes. Otol
Neurotol. 2008;29:23–28.

43. SURGICAL APPROACHES OF
ATRESIAPLASTY
• Three possible approaches can be followed for
congenital aural atresia repair. They are:
1. Anterior
2. Modified anterior
3. Mastoid

44. ANTERIOR APPROACH
• Is the most common approach used these days.
• In this approach a post auricular incision is made and the
subcutaneous tissue and periosteum are raised anteriorly
up to the level of glenoid fossa.
• If any remnant of tympanic bone is present drilling is
started at the cribriform area, and if no tympanic bone is
present the drilling begins at the temporal line just
posterior to the glenoid fossa.
• Drilling is continued anteriorly and medially till
epitympanum is entered.
• The most common anamoly encountered in the middle ear
of these patients is a fused malleal - incudal joint. Stapes is
usually normal in these patients.

45. • The atretic bone is carefully removed uncovering the
ossicles.
• The facial nerve usually lie medial to the ossicular
mass, and must be protected at all costs.
• Drilling is continued till the canal is about 10mm in
size.
• Ossicular chain reconstruction is performed and a neo
tympanum is fashioned using temporalis fascia graft.
• Split thickness skin graft is used to line the external
auditory canal.
• A wide meatoplasty is fashioned and a large wick is
inserted to stent the canal.

46. MODIFIED ANTERIOR APPROACH
• This approach is used in patients with a thick atretic
plate because of poor orientation during dissection.
• This poor orientation may risk carotid artery, facial
nerve, and lateral semicirular canal to injury.
• Orientation in these patients could be achieved by an
initial posterior dissection up to the level of sinodural
angle. This enables the surgeon to identify the level of
lateral canal and ossicular mass. From here on the
approach is similar to that described under anterior
approach

47. MASTOID APPROACH
• In this approach the external auditory canal is
created at the expense of mastoid cavity.
• It involves drilling out the mastoid and
identifying the sino-dural angle.
• This is a risky procedure because of distorted
anatomy of the facial nerve in these patients.

48. COMPLICATIONS OF ATRESIAPLASTY
• Facial Nerve Inury – Transient or Permanent
• SNHL
• External auditory canal wall stenosis
• Lateralized tympanic membrane causing CHL
• Recurrent acute otitis, otitis media with
effusion, retraction pockets, cholesteatoma,
mastoiditis, chronic suppurative otitis media,
tympanic membrane perforation, or any other
disease of the ear

49. CONGENITAL EXTERNAL AUDITORY
CANAL STENOSIS
• Congenital external auditory canal stenosis (CEACS) is
defined by Jahrsdoerfer et al. as an EAC with a
diameter of less than 4 mm.
• A four level classification of CEACS was developed by
Schuknecht.
• Meatal stenosis occurs as a result of partial lack of
embryologic canalization of the EAC from the usual
medial to lateral direction.
• Isolated meatal stenosis may be repaired, if severely
narrow, via canaloplasty with drilling of the bony ear
canal and thinning of the soft tissues with skin flap
preservation.

50. ALTERNATIVES FOR CONGENITAL AURAL ATRESIA:
IMPLANTABLE HEARING AIDS IN CHILDREN
• Several types of implantable hearing aids may
be used for hearing rehabilitation of CAA in
children over 5 years of age, as an alternative
to atresiaplasty:
– percutaneous (crosses skin) bone-conduction
devices (BAHA, Ponto),
– transcutaneous (closed-skin) bone-conduction
devices (Sophono), and
– active middle ear implants (Vibrant Soundbridge).

51. BAHA
• Was first described by Tjellström and colleagues.
• BAHA is considered the gold standard in terms of closure of
the air-bone gap and the air-conduction PTA gain in
children with CAA.
• The BAHA/Ponto may be useful for children with CAA who
have unfavorable anatomy for reconstruction, those who
are poor candidates for a lengthy atresiaplasty procedure
for medical reasons, or for families that desire good hearing
with less surgical risk.
• The standard surgical procedure includes the placement of
a titanium fixture in the temporal bone with the reduction
of the subcutaneous tissue and creation of a zone of
alopecia around the abutment

52. • The standard surgical procedure includes the
placement of a titanium fixture in the temporal
bone with the reduction of the subcutaneous
tissue and creation of a zone of alopecia around
the abutment
• The planned site for BAHA placement is 5.5 mm
posterosuperior to the EAC or planned site of the
EAC.
• It is 6.5 to 7.0 cm from the planned site of the
EAC in ears with planned future microtia
reconstruction, rather than the usual 5.5-cm
distance.

53. • The image of the BAHA shows how a button (or stud
if you prefer) is inserted into the bone of the skull
above the ear.

54. COMPLICATIONS OF BAHA SYSTEMS
• Bone
– Failure of osseointegration
– Chronic infection
– Trauma
• Soft tissue
– Irritation of the skin surrounding the implant
– Skin flap necrosis (death of the skin flap, e.g. due to
interrupted blood supply)
– Overgrowth of skin over the device
– Wound dehiscence (splitting apart of the wound)
– Bleeding or hematoma formation
– Persistent pain

55. The BAHA device is attached to the
button within the skull. It is unobtrusive
(once the hair is put back into place).
(image is from Island Hearing. )
The PONTO device is attached to an
abutment (i.e. stud) behind the ear
(image is from Ponto web site. )
The SOPHONO device is attached using a
magnet (image is from Sophono web
site. )