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Congenital Aural Atresia
Hwa J Son, M.D.
Faculty Advisor: Tomoko Makishima, MD, PhD
October 17, 2007
UTMB Otolaryngology
Grand Rounds Presentation
Epidemiology
• 1 in 10,000 to 20,000 live births
• Male > Female
• Right side > Left side
• Unilateral > Bilateral (3:1)
• Bony atresia > Membranous
Embryology
• 1st branchial groove forms meatal plate at 6
- 8 wks resorbs/forms EAC at 21st wk
• Auricle
– 1,2 BA
– 8 -12 wk
• Middle Ear
– 1,2 BA
– 5 -12 wk
• Inner ear
– otic capsule
– 3 - 20th
wk
Associated Ear Deformity
• Common
– Middle Ear
•Malleus/Incus fusion
– External Ear
•Microtia
•Severity of microtia correlates with
malformation of middle ear
• Uncommon
– Stapes footplate
– Inner Ear problems
Etiology
• Sporadic
• Syndromic (11-47%) – Goldenhar’s,
Treacher-Collins, branchio-oto-renal
syndrome, de Grouchy syndrome (18q-) and
Crouzon syndrome.
• Familial– within immediate family
4.9%, extended family 10.3%
Non-Syndromic Associations
• Facial asymmetry (36.5%)
• FN weakness (15.2%)
• Cleft lip/palate (4.3%)
• Urogenital defects (4%)
• CV malformation (2.5%)
• Macrostomia (2.5%)
• Congenital cholesteatoma (4-7%)
History
• Hx of teratogens
– microtia- thalidomide, isoretinoin,
vincristine, cholchicine, cadmium
• Family hx
• Hearing status, speech development,
past surgical procedures
• Frequency of otitis media
Physical Exam
• Location of condyle: posterior position
poor prognosis – atretic plate and ME
are poorly developed
• Size of mastoid (palpate mastoid tip,
spine of Henle, condyle, zygomatic
arch)
• Craniofacial anomaly
• Severity of microtia
Grades of Microtia
Schucknecht Classification
Audiological Assessment
• When: ABR within 2-3 months of birth
• Results
– Bone conduction usually normal
– Air conduction maximal at 60dB
• Intervention
- Normal or u/l confirm with behavioral
audiogram at 6 M age, no need for aid
- B/L: Need bone conduction hearing aid, early
speech therapy
Imaging
• When? At several months
• Look for
– Status of the inner ear
– Extent of temporal bone pneumatization;
– Course of the facial nerve
– Presence of the oval window/stapes footplate.
• Also important
– Size of bony atretic plate
– Soft tissue contribution to the atresia
– Size/status of the middle ear cavity
– Presence/absence of congenital cholesteatoma.
Example 1
Example 2
Jahrsdoerfer Grading System
Parameter Points
Stapes 2
Oval window open 1
Middle ear space 1
Facial nerve normal 1
Malleus-incus complex present 1
Mastoid well pneumatized 1
Incus-stapes connection 1
Round window normal 1
Appearance of external ear 1
Treatment Options
• Non-reconstructive option
– Bone conduction hearing aids
– BAHA
• Atresiaplasty +/- auriculoplasty
Non-Reconstructive Option
• Bone conduction hearing aid (BCHA)
– Ideally before age 6M for b/l CAA.
BAHA
• Surgically-implanted, percutaneous
titanium screw fixture
• Osseointegrates into the temporal
bone.
Advantages of BAHA
• Sound energy is not attenuated by the
skin and intervening soft tissues
• More comfortable at contact site
• Does not preclude
reconstruction later
on because of
surgical scars
Surgery for BAHA
• Needs 2-stage surgery in young
children (age 2-10)
– 1st: titanium screw
– 2nd
: 3M later, skin-penetrating abutment
• Complications limited to:
– local infection / inflammation (7.5%)
– failure to osseointegrate (2.5%)
BAHA Results
• Grandstrom(1993, L4)
– 100% subjective satisfaction and speech
thresholds <30 dB in 39 pt with J’s Score <6,
• Hakansson et al.(1995, L4)
– 147 pt. PTA <45 dB 89% with subjective
improvement.
– PTA 46-60 with 61% and PTA >60 with 22%
• Lustig et al.(2004, L4)
– 40 pt (9 w/ CAA) - ABG closure of <10 in 80%, <5
in 60%.
2004 BAHA Consensus
Statement (L5)
• BAHA best option when:
– ABG>30 with external canal occlusion
– tx resistant OM
• B/l case, give b/l
conductive aid before
age 6M
• Awaiting reconstruction:
– BAHA can be used in
children <2yo with
steel or elastic band
Reconstructive Surgery
Goal of Reconstructive Surgery
• Create a patent, skin-lined EAC
• Postoperative air-bone gap within 20
to 30 dB.
• Long term hearing result that is
adequate for speech/language
development in children
• Cosmetically appealing auricle
Difficulty of Surgery
• Altered anatomy, absence of
anatomical landmarks
• Fear of injuring FN
• SNHL from drilling
• Difficulty of placing skin graft
• Chance of meatal stenosis
• Concern of post-op infection
Staging of Surgery
• Stage 1: Cartilage graft harvest,
sculpturing, implantation
• Stage 2: Lobule repositioning (z-plasty
to more posterior/inferior)
• Stage 3: Elevation of auricle
• Stage 4: Tragus formation,
atresiaplasty
Contraindications
• Significant SNHL or inner ear malformation.
• Limited middle ear–mastoid pneumatization
or a significantly hypoplastic middle-ear
cleft.
• Anomalous facial nerve or aberrant major
vascular structure.
• Middle cranial fossa tegmen sagging
– Would restrict anatomic access to the middle-ear
cleft.
Timing of Surgery
• Start at age 6Y or later.
• Limitations for earliest date
– Rib cartilage maturation
– Post-op cooperation
• Reconstruction of auricle first
– Chance of success/healing best without
vascular compromise
• Operate on better ear first
Canaloplasty
Tympanoplasty, Skin grafting
Meatoplasty
Pitfalls
• Second genu makes acute angle turn
instead of 90°
– Vertical course crosses the middle ear
Follow-up Care
• Meatal suture out in 7 days
• Packing removed at 2 and 3 wks
• Antibiotic drops for 8-12 wks
• Audiogram at 8 wks, 6 M and yearly
• New ear canal must be debrided under
microscope q 6-12M
Final Cosmetic Result
Hearing Results
• Jahrsdoerfer (1992, L4)
– 90 operated on, 37 with grade 8-9.
– SRT <10 in 11% and SRT 10-25 in 78%
• Chandrasekhar (1995, L4)
– 92 pt, ABG <30 in 60% of primary and in 54% of
revision sx
• Murphy (1997, L4)
– 33% of partial atresia with SRT <20 dB and 15%
of total atresia
• De La Cruz (2003, L4)
– 116 ears, 58% ABG <30 for primary, 56% for
revision
Long Term Hearing
• De La ruz (2003, L4)
– 90 ears with >6M f/u.
– PTA: 59.9dB 45.3 dB 52.5 dB
– ABG: 45.1 dB 28.1 dB 32 dB
• Hearing gets worse long term, but not
statistically significant
• Ossicular chain refixation the most
common cause of HL
Results Summary
• Surgeon dependent
• What’s termed success varies between
studies
– May not be appropriate for pre-school
and school aged children (SRT <15 per
audiology literature)
Complication
• Lateralization of TM (22-28%)
– up to 12 M post-op
• Meatal stenosis (cartilagenous >
bony): 8-12%
• SNHL – inner ear damage (2%)
• Facial nerve injury (<1%)
• Fixation/discontinuity of ossicles
(11.5%)
Measures to Avoid Complication
• Lateralization of TM
– Cut off nitrous oxide 30 min before grafting.
– The graft anchored medially to the malleus and
the tab placed into the protympanum.
– Use of silastic button.
• Stenosis:
– Use of large STSG
– Merocel wicks
• SNHL:
– Caution with drilling,
– Use laser
• FN injury
– Intra-op monitor
“Surgery or implantable hearing
devices?”
Surgery vs. BAHA
• Evans (2006, L4)
• Compare hearing results, complications, cost
Reconstructed BAHA
2-stage
BAHA
1-stage
Hearing
gain
17.3 dB per ear 31.8 31.8
Cost $51506 $42449 $28341
Cost/dB $2909 $1238 $826
Results
• Cost
– BAHA covered by Medicare
– Cost about 1/4 of sx per dB gain
• Hearing
– 93% of reconstructive sx pt still needed some
form of sound amplification
– BAHA achieves HL <15dB with normal bone
curves
• Complications
– Reconstruction : Canal stenosis (22.2%), ROE
(19%), canal prolapse(5%), cholesteatoma (3%)
– BAHA with fewer serious complications: 1/6 with
hypertrophic scar
BAHA for Binaural Hearing
Use of BAHA in Unilateral CAA
• Wazen et al.
– Prospective case series with 9 pt.
• Pt benefited in tonal, spondee
threshold
• Significant improvement in handicap
score (from questionnaire)
• Gain binaural benefit in
localization/speech perception in
noise
Case Presentation #1
53 yo M with no other signif PMHx presents to B-clinic as a referral from
audiology. He has Left microtia s/p microtia repair? at age 9 in Mexico,
wearing BCHA on right side. He wishes to be re-fitted for another BCHA.
Case Presentation #1
Case Presentation #2
• RP is a 10 M old boy presenting to
pedi ENT clinic for f/u after failing OAE
as a newborn on Right side.
• PE showed left microtia with narrow
EAC at bony-cartilaginous junction.
Right side stenotic, TM not visualized
• ABR showed repeatable V-wave
– Left: <30dB HL air stimulation
– Right: <30dB bone stimulation
Conclusion
• Early identification of problem important for
hearing amplification and special education
• Patient classification with audio/CT
important for predicting results of sx
• Severity of microtia predict ME deformity
• BCHA should be fitted before age 6M for b/l
• BAHA with better audio results and
satisfaction than BCHA for non-sx candidate
• Sx needs careful planning with
multidisciplinary effort, careful timing
Conclusion
• Surgery
– Questionably adequate audio result for
children
• BAHA
– Good hearing results and more cost
effective for hearing gain
• Binaural BAHA
– Recommended for further gain in speech
in noise and localization
Bibliography
• Nuijten I. Admiraal R. Van Buggenhout G. Cremers C. Frijns JP. Smeets D. van Ravenswaaij-Arts C. Congenital aural atresia in 18q deletion
or de Grouchy syndrome. [Case Reports. Journal Article]Otology & Neurotology. 24(6):900-6, 2003 Nov. UI: 14600472
• Dostal A. Nemeckova J. Gaillyova R. Vranova V. Zezulkova D. Lejska M. Slapak I. Dostalova Z. Kuglik P. Identification of 2.3-Mb gene locus
for congenital aural atresia in 18q22.3 deletion: a case report analyzed by comparative genomic hybridization. [Review] [46 refs] [Case
Reports. Journal Article. Research Support, Non-U.S. Gov't. Review] Otology & Neurotology. 27(3):427-32, 2006 Apr.
• Wazen JJ. Spitzer J. Ghossaini SN. Kacker A. Zschommler A. Results of the bone-anchored hearing aid in unilateral hearing loss. [Journal
Article] Laryngoscope. 111(6):955-8, 2001 Jun.
• Granstrom G. Bergstrom K. Tjellstrom A. The bone-anchored hearing aid and bone-anchored epithesis for congenital ear malformations.
[Comparative Study. Journal Article. Research Support, Non-U.S. Gov't] Otolaryngology - Head & Neck Surgery. 109(1):46-53, 1993 Jul.
• Jahrsdoerfer RA. Yeakley JW. Aguilar EA. Cole RR. Gray LC. Grading system for the selection of patients with congenital aural atresia. [Case
Reports. Journal Article] American Journal of Otology. 13(1):6-12, 1992 Jan.
• Murphy TP. Burstein F. Cohen S. Management of congenital atresia of the external auditory canal. [Journal Article] Otolaryngology - Head
& Neck Surgery. 116(6 Pt 1):580-4, 1997 Jun.
• De la Cruz A. Teufert KB. Congenital aural atresia surgery: long-term results. [Journal Article] Otolaryngology - Head & Neck Surgery.
129(1):121-7, 2003 Jul.
• Jahrsdoerfer RA. Yeakley JW. Aguilar EA. Cole RR. Gray LC. Grading system for the selection of patients with congenital aural atresia.
[Case Reports. Journal Article] American Journal of Otology. 13(1):6-12, 1992 Jan.
• Murphy TP. Burstein F. Cohen S. Management of congenital atresia of the external auditory canal. [Journal Article] Otolaryngology -
Head & Neck Surgery. 116(6 Pt 1):580-4, 1997 Jun.
Bibliography, pt. 2
• Ear and Temporal b one Surgery. Wiet. 2006. Thieme
• Pediatric Otolaryngology. Wetmore et al. 2000 Thieme
• Evans AK. Kazahaya K. Canal atresia: "surgery or implantable hearing devices? The expert's question is
revisited". [Journal Article] International Journal of Pediatric Otorhinolaryngology. 71(3):367-74, 2007
Mar.
• Chandrasekhar SS. De la Cruz A. Garrido E. Surgery of congenital aural atresia. [Journal Article]
American Journal of Otology. 16(6):713-7, 1995 Nov.
• Snik AF. Mylanus EA. Proops DW. Wolfaardt JF. Hodgetts WE. Somers T. Niparko JK. Wazen JJ. Sterkers O.
Cremers CW. Tjellstrom A. Consensus statements on the BAHA system: where do we stand at present?.
[63 refs] [Consensus Development Conference. Journal Article] Annals of Otology, Rhinology, &
Laryngology - Supplement. 195:2-12, 2005 Dec.
• Lustig LR. Arts HA. Brackmann DE. Francis HF. Molony T. Megerian CA. Moore GF. Moore KM. Morrow T.
Potsic W. Rubenstein JT. Srireddy S. Syms CA 3rd. Takahashi G. Vernick D. Wackym PA. Niparko JK.
Hearing rehabilitation using the BAHA bone-anchored hearing aid: results in 40 patients. [Clinical Trial.
Journal Article. Multicenter Study] Otology & Neurotology. 22(3):328-34, 2001 May.
• Hakansson B. Liden G. Tjellstrom A. Ringdahl A. Jacobsson M. Carlsson P. Erlandson BE. Ten years of
experience with the Swedish bone-anchored hearing system. [Comparative Study. Journal Article] Annals
of Otology, Rhinology, & Laryngology - Supplement. 151:1-16, 1990 Oct.
• Jahrsdoerder, RA., Mason, JC. Congenital aural atresia. Operative Techniques in Otolaryngology-Head
and Neck Surgery, Vol 14, No 4 (Dec), 2003: PP247-151