Ear - Congenital Anomalies & Correction Flashcards
Describe anatomy of ear
Antihelix antitragus complex helix lobule complex concha/scapha/tringular fossa depressions Crus of helix
What is the vascular supply to the ear
posterior auricular STA
What is the innervation to the ear
- Greater auric (C2,3) - lower 1/2
- ATN (V3) - tragus and crus
- Lesser occipital Arnold’s nerve CNX - EAM
- Jacobson CNIX - posterior EAC
What are antropometric landmarks/rules for the position of the ear
20’ off axis from line parallel to nasal dorsum Top of ear in line with lateral brow Bottom of ear in line with columella Ear should be one ear length behind lateral orbital rim Ear should protrude 1-2cm from skull with angle 20-25degrees at level of tragus
Describe the embryology of the ear
Ear development is divided into Inner and MIddle/External
Inner ear - ectoderm - otic placode->pit->otocyst-> semicircular canals, endolymph sacs, organ of corti
Middle extenal - derived from branchial structures 3wks->6mths
Branchial arch 1: Merckel cartilage (Incus Malleus), anterior hillocks (tragus, crus, helix)
Branchial arch 2: Recikert cartilage (stapes), posterior hillocks (antihelix, antitragus, lobule)
Branchial cleft 1: EAC and meatus
Branchial pouch 1: Eustachian tube
Classify congenital ear anomalies
Nagata classification
- Lobule-type microtia (no concha/meatus/tragus)
- Choncal-type microtia (includes concha/tragus)
- Small-concha type (less developed than type 2)
- Anotia
- Atypical microtia
Define microtia
defined as a small ear - includes spectrum of ear abnormalities from small ear to complete anotia
What is the epidemiology of congenital ear deformities?
M>F 3:2 Bilateral most common in syndromic cases R>L>Bi 6:3:1 Highest incidence in navajo and japan
What is the hereditary patterns of microtia?
- variable penetrance or dominant/recessive traits - dominant inheritance for protruding, appendages/preauricular pits
What are associated abnormalities with microtia?
- middle ear abnormalities (half of normal hearing)
- congenital syndromes (TC, HFM, G, T18, BOR)
- CN7 weakness
- Branchial arch deformities**** (1/3)
- Cleft lip/palate
- CV, renal
- Macrostomia
What congenital syndromes are associated with microtia?
MAINLY bilateral
- Treacher collins
- HFM
- Goldenhar syndrome
- Trisomy 18
- Brachi-otorenal syndrome
What syndromes should you think of when you seen bilateral microtia?
TC HFM G T18 BOR
What are options for management of microtia
Non-surgical
- camouflage
- prosthesis
Surgical
- autologous recon
- alloplastic recon (silicone, medpor)
- prefabricated engineered frameworks (remain experimental)
- prothesis with OI implant
What are the ADv/Disad of autologous vs alloplastic recon vs prostheis w OII
Autologous - lower comx rate (exposure/infection) - multiple OR, donor site mrbidity Alloplastic - high exposure/infectionr ate - may eliminate chance of autologous recon Prosthesis - need replacements over lifetime
What are the difference between brent and nagat techqnieues for autologous microtia recon
- Timing
- # stages
- Cartilage harvested
- Suture material
BRENT
- 4 stages, age 5-8
- Contralateral rib 6-8, clear nylon suture
NAGATA
- 2 stages, age 10 or chest circum >60cm
- Ipsilat 6-9, steel wire
What are criticism of brent technique
- too many stages(4)
- poor definition concha, antitragal region
- loss of auriculocephalic contour
What are criticism of nagata technique
- chest wall defomirty
- flap necrosis
Describe the 4 stages of Brent Technique (starts at age 5-8)
- Cartilage Harvested, Framework carved and positioned in pocket between dermis and TPF, ala, commisure, canthus used for position
- Lobule transposition with z-plasty
- Create auricolocepahlic sulcus with banked wedge and skin graft
- Tragus reconstruction with conchal graft from normal ear
Describe Nagata Technique (2stages, starting from 5-10yrs when chest circumf >60cm)
- Cartilage harvest, framework carved including tragus and placed, Lobule transposed.
- Create auriculocephalic sulcus with TPF flap
Describe Nagata framework
Multilayer
Base framework
+ Helix + crus helicis
+ Antihelix
+ Superior crus + Inferior Crus
Describe complications of autologous reconstruction for microtia repair
EARLY
- PTX
- Wound dehiscence, skin flap loss
- infection, hematoma, seroma
- graft loss
LATE
- chest wall deformity
- malposition
- framework resorption
- poor scarring
- suture/framework exposure
What are your options for failed reconstruction
1- Re-attempt autologous recon (excise scar, use TPF is not used by nagata techqnieue
2- prosthesis with or not OIimplant
Classify congenital ear abnormalities
1- Microtia
2- Prominent ear
3- Constricted ear
4- Cryptotia
5- Stahl’s ear
6- Preauricular tags/sinuses
Define Ear Prominence
- Helical rim to mastoid distance at level of tragus >2cm
- Conchoscaphal angle >35 degrees
- Adequate helical rim/length (as oppose to constricted ear)
Describe the inheritance pattern/etiology
Variable penetrance of AD trait
Due to high estrogen levels and cartilage plaibilty
Describe the pathophysiology of the prominent ear
1- Poorly develop anti-helical fold
2- Overly developed conchal wall
3- Combination of both
Describe Anatomic characteristis (5)
- Poor definition of antihelix w flat superior crus
- Conchal height excess
- increase angle from helical rim to scalp
- Scaphoconchal angle >90
- normal helical length
What do you manage ear prominence?
Non-surgical
- camouflage
- moulding ***initiate with 72hrs of birth to tak eadv of circulatinghormones
Surgical
- Antihelix manipulation (Mustarde, Stenstorm, Luckett or Converse-Wood)
- conchal manipulation (Furnas Cm sutures)
- Conchal excision
Describe technique for antihelix manipulation
- Mustarde: recreate antihelix fold and reduce scophoconchal angle (posterior approach
- Stenstrom: scoring anterior surface
- Luckett or COnverse-wood: Full thickness excision
Describe technique for Conchal manipulation
- Furnas: (CM sutures) Reduce of conchal prominence with excision of skin, postauric muscle and ligament and conchomastoid sutures
- Conchal excision: used ofen in combo with furnas CM suture
Describe post-operative course after prominent ear correction surgery
Close f/u to assess for complications
Head wrap/band for 3-6wksto protect during sleep/activity
What are complications of ear prominence correction surgery
EARLY
- hematoma, infection, chondritis, necrosis
LATE
- poor scarring
- recurrence
- suture exposure
- injury to GAN
- sharp edges, poor correction
Define Constricted ear
Inadequate helical rim/circumference
What is a lop ear and cup ear
Older terms for Constricted ear
- Lop ear: inadequate helical rim + missing scapha, poor antihelix
- Cup ear: inadequate helical rim + poor antihelix+ deep concha
How do you classify Constricted ear?
Tanzer classification
- Type 1 - Helix involved only
- Type 2A - Helix and scapha invovled, sufficient skin
- Type 2B - Helix and scapha involved, NOT sufficient skin
- Type 3 - Helix, scapha and concha invovled, - some classify as microtia
How do you manage constricted Type 1 (Helical rim involved only)
Mark where normal Height of helix should be
1- Lid of extra skin excised
2- Prominent upper pole set back with scapho-mastoid suture
How do you manage constricted type 2A (helix and and scapha invovled with enough skin)
Deglove upper cartilage structures
Cartilage graft for increasing helical rim
How do you manage constricted type 2B (helix and and scapha invovled with NOT enough skin)
- Split ear at middle 1/3 to open ear up
- chondrocutaneous flap from conchal bowl for anterior defect and retroauricular skin for posterior skin defect created
How do you manage constricted type 3 (helix scapha antihelix concha invovled )
Reconstruciton as per microtia (too small of an ear - needs framework)
Defien Cryptotia
Upper pole of ear fails to stand out from head (helical rim is buried superiorly under temporal tissues ) - lack of fold superiorly)
What are anatomic characteristics of Cryptotia?
- buried superior pole of helix
- scapha underdeveloped
- sharp antihelix
common in asians
How do you manage cryptotia
Non surgical
- camouflage
- early splinting
Surgical
- recreate auriculocephalic sulcus w zplasty, VY adv
Define Stahl ear
Deformity with a third crus traversing traingular fossa forcing rim up at the jx point
How do you manage stahl ear
non-surgical - splinting
Surgical
-direct excision/rotation and suturing
Define preauricular sinus/cyst
INcomplete fusion of 6Hillocks with extodermal invagination/entrapment
Located anterior to EAC, at ascending crus of helix
How to do you manage preauricular cyst/fistula/sinus
Usually asymptomatic
Conservative if no infection
If symptomatic
complete excision of sinus/tract + part of helical cartilage
Define preauricular tag
mound of epithelium pedunculated in preauric area
Do not contian cartilage/bone and are not connected to ear structures
What syndromes/disorders are associated with preauricular tags?
BOR syndrome brachio-otorenal
OAV syndrome oculoauriculovertebral
What are complications associated with OIimplants
CSf leak, open mastoid air cells
skin irritation
