Techniques for Pinna Reconstruction

INTRODUCTION

• Microtia (congenital underdevelopment) - most common indication
• Traumatic avulsion or amputation
• Post-oncologic resection (e.g., squamous cell carcinoma of the pinna)
• Burns
• Congenital anotia

CLASSIFICATION OF MICROTIA (BASIS FOR SURGICAL PLANNING)

OPTIONS FOR PINNA RECONSTRUCTION

1. Autologous reconstruction (rib cartilage framework)
2. Alloplastic reconstruction (porous polyethylene implant)
3. Prosthetic reconstruction (bone-anchored auricular prosthesis - BAAP)

1. AUTOLOGOUS RIB CARTILAGE RECONSTRUCTION

• Construction of a cartilaginous framework
• Soft-tissue coverage
• Projection of the reconstructed pinna

A. TANZER TECHNIQUE (Historical - First Systematic Approach, 1959)

1. Lobule transposition
2. Cartilage framework creation and insertion into a subcutaneous pocket
3. Framework elevation (creation of retroauricular sulcus)
4. Tragal construction and conchal deepening

B. BRENT TECHNIQUE (4-Stage)

• Baseplate from synchondrosis of ribs 6/7; helix from rib 8
• Less three-dimensional detail (no antihelical feature carved separately)
• Atypical appearance persists until lobule transposition at Stage 2
• Requires less cartilage than Nagata - can be done at age 6-7 years
• Can be combined into 3 stages with modifications

C. NAGATA TECHNIQUE (2-Stage) - Most Widely Used

Stage 1 - Framework construction and insertion:

• Performed at age ≥10 years (chest circumference ≥60 cm)
• Lobule split and transposition performed at same time
• Framework carved with overall thickness of 10-14 mm using scalpel, punch biopsies, and gauges
• Components:
  • Base plate (from ribs 6/7 synchondrosis): conchal bowl, scaphoid fossa, triangular fossa carved in
  • Helix (rib 8) - contoured around the base plate
  • Antihelical element (rib 9 may accentuate antihelix)
  • Intertragal complex (from remainder of 6/7 synchondrosis)
• Framework inserted into subcutaneous pocket
• Residual cartilage banked over muscle for use in Stage 2
• Drain placed for tight soft-tissue adherence onto framework

Stage 2 - Ear projection (6 months later):

• Posterior auricular incision peripheral to the neohelix
• Ear framework elevated, creating retroauricular sulcus
• Banked cartilage harvested, carved into crescentic shape for projection block placed posterior to conchal bowl
• Posterior scalp flap (widely elevated) advanced anteriorly and sutured to periosteum
• Anteriorly-based postauricular fascial flap covers the projecting cartilage block
• Full-thickness skin graft (from inguinal region or chest) covers posterior surface of neoauricle

D. PARK TECHNIQUE (Expanded Two-Flap Method, 3-Stage)

• Upper portion placed between skin and fascial flaps
• Lower portion inserted in the earlobe envelope
• Anterior surface covered by skin flap
• Fascial flap drapes the posterior portion
• Skin graft (from groin or scalp) covers exposed fascial flap

2. ALLOPLASTIC RECONSTRUCTION (MedPor/SuPor - Porous Polyethylene)

1. Postauricular incision; excision of remnant cartilage
2. Temporoparietal fascial (TPF) flap raised for coverage (vascular supply from anterior and posterior superficial temporal vessels)
3. TPF may be harvested endoscopically through the postauricular incision (avoids alopecia and scar)
4. Alloplastic implant positioned
5. TPF flap draped over implant
6. Full-thickness skin graft placed over the fascial flap

• Single-stage procedure
• No rib donor site morbidity
• Can be performed at younger age (does not depend on rib cartilage volume; possible from age 3)
• Less dependence on framework carving skill
• Excellent aesthetic outcomes possible

• Higher rates of fracture, extrusion, infection
• Needs significant postoperative maintenance
• Less resilient than autologous cartilage
• Exposed implant rates are well-documented

3. BONE-ANCHORED AURICULAR PROSTHESIS (BAAP)

• Lack of autogenous tissue
• Irradiated area (poor wound healing)
• Failed autologous reconstruction
• Cancer resection
• Absence of lower half of pinna
• Patient preference
• Significant comorbidities
• Craniofacial anomaly

• Requires removal of vestigial ear including lobule - precludes subsequent autologous reconstruction
• Two osseointegrating fixtures are placed (position agreed by surgeon and prosthetist)
• Single- or two-stage surgery (similar to BAHA insertion)
• After osseointegration, a gold retention bar attached to abutments
• Prosthetic ear clips onto this bar

• Prosthesis lasts only 6 months to 2 years before wear becomes apparent
• Seasonal skin tone changes make prosthesis distinction apparent
• Recurrent soft-tissue inflammation around percutaneous abutments
• Traumatic fixture loss
• Patients may not feel it is "part of themselves"
• Significant cost and maintenance

4. RECONSTRUCTION FOR TRAUMATIC DEFECTS

• Small partial defects: primary closure or local flaps
• Helical defects: Antia-Buch chondrocutaneous advancement flap (for upper/middle third) - based on subcutaneous pedicle
• Composite grafts from contralateral ear for small defects
• For larger peripheral defects: 3-step rib cartilage reconstruction

• Prosthesis is the most common offering following parotidectomy/pinna excision and radiotherapy
• Autologous reconstruction less frequently performed due to irradiated bed

5. FLAP OPTIONS FOR COVERAGE

COMPLICATIONS

COMPARISON TABLE: AUTOLOGOUS vs ALLOPLASTIC vs PROSTHETIC

CONCLUSION

Perforators of the Pinna for Reconstruction

ARTERIAL SUPPLY - OVERVIEW

1. Superficial Temporal Artery (STA) - anterior supply
2. Posterior Auricular Artery (PAA) - posterior supply

1. SUPERFICIAL TEMPORAL ARTERY (STA) - ANTERIOR AURICULAR BRANCHES

2. POSTERIOR AURICULAR ARTERY (PAA) - PERFORATORS

Specific Perforating Points (PAA perforators through cartilage):

• Supplies skin of the mastoid/retroauricular region (basis of postauricular flaps)
• Stylomastoid branch enters the fallopian canal and supplies the inferior segment of the facial nerve (clinically important in parotid/mastoid surgery)

3. ANASTOMOTIC NETWORK - SURGICAL IMPORTANCE

• In the concha
• Along the helix
• Along the antihelix
• Alongside the tragus
• Superior STA branch ↔ PAA anastomosis at the superior helix

• Composite grafts survive well (rely on peripheral revascularization)
• Postauricular flaps are robust with minimal necrosis risk
• The pinna tolerates replantation and staged elevation better than many body parts

4. SURGICAL RELEVANCE - FLAP DESIGN BASED ON PERFORATORS

A. Postauricular Island Flap (Masson 1972)

• Based on auricular branch of PAA + STA
• Axial flap design based on one of the major divisions of PAA
• Covers defects of helix, scaphoid fossa, concha, EAC
• Single-stage; rich vascular supply; minimal flap necrosis risk
• Donor site closed primarily (well-hidden scar in retroauricular sulcus)
• Designs: superiorly pedicled (superior pole defects), inferiorly pedicled (lower pole/lobule defects), subcutaneous pedicle propeller island flap

B. Antia-Buch Chondrocutaneous Advancement Flap (1967)

• Used for helical rim defects (middle and upper third)
• Relies on posterior auricular skin left intact to provide blood supply via PAA perforators
• Helical rim incisions through anterior skin and cartilage only; posterior auricular skin remains attached
• Posterior auricular skin is freed from conchal cartilage to allow advancement
• The uncut posterior auricular skin = the vascular pedicle

C. Temporoparietal Fascial (TPF) Flap

• Based on the superficial temporal artery (parietal branch)
• Used to cover alloplastic (MedPor) frameworks in microtia reconstruction
• Thin, well-vascularized; allows skin graft adherence
• Can be endoscopically harvested to reduce alopecia risk

D. Earlobe-Based Advancement Flap (ELBAF)

• Newer technique based on the inferior and middle STA branches converging at the earlobe
• Arteries from earlobe run superiorly along helical rim
• Simpler alternative to Antia-Buch for helical defects

E. Preauricular Flaps

• Based on STA anterior auricular branches
• Used for anterior surface defects of pinna

5. VENOUS DRAINAGE

6. LYMPHATIC DRAINAGE (Clinically Important for Malignancy)

7. PRACTICAL SURGICAL PRINCIPLES FROM PERFORATOR ANATOMY

1. Never thin the skin over the framework excessively - PAA perforators enter through specific cartilage windows; an overly thin flap sacrifices the subdermal plexus
2. Posterior auricular skin is the workhorse - rich PAA supply makes it the most reliable donor tissue
3. Leave posterior skin intact in Antia-Buch - it is the sole blood supply to the advanced chondrocutaneous flap
4. STA-PAA anastomoses protect composite grafts - peripheral revascularization allows composite graft survival up to ~1.5 cm
5. Skin necrosis in embolic occlusion - the pinna is particularly susceptible to cutaneous branch emboli from the ECA (important in embolization procedures)
6. TPF flap elevation must preserve the superficial temporal vessels (run just under the temporoparietal fascia, superficial to deep temporal fascia)

SUMMARY DIAGRAM

External Carotid Artery
├── Superficial Temporal Artery (STA) [ANTERIOR supply]
│   ├── Superior anterior auricular branch → ascending helix, upper pole
│   ├── Middle anterior auricular branch → tragus, upper lobule
│   └── Inferior anterior auricular branch → lobule, lower helix
│                ↕ anastomoses (concha, helix, antihelix, tragus)
└── Posterior Auricular Artery (PAA) [POSTERIOR supply]
    ├── Retroauricular skin branches → postauricular skin (flap basis)
    ├── Perforators through cartilage:
    │   ├── Triangular fossa
    │   ├── Cymba conchae
    │   ├── Helical root
    │   └── Concha
    └── Stylomastoid branch → facial nerve (inferior segment)