What are the differences between the Nagata and Brent techniques for microtia reconstruction?

Differences Between Nagata and Brent Techniques for Microtia Reconstruction

The Nagata technique offers more detailed cartilage framework construction but has higher complication rates compared to the Brent technique, which uses a simpler framework but requires more surgical stages.

Overview of Both Techniques

Brent Technique

• A four-stage approach to microtia reconstruction using autologous costal cartilage 1
• Stages include:
  1. Creation and placement of the cartilage framework from 6th-8th ribs
  2. Lobule rotation from microtia remnant
  3. Ear elevation with skin graft to create the auriculocephalic angle
  4. Tragus formation using composite graft from the opposite ear 1
• Lower complication rate of approximately 2.98% compared to Nagata's 12.2% 2

Nagata Technique

• A two-stage approach that creates a more detailed three-dimensional framework 3
• Stages include:
  1. Implantation of a detailed cartilage framework and ear lobe transposition in a single procedure
  2. Ear elevation using temporoparietal fascia flap (in original technique) 4
• Higher complication rate of approximately 12.2% 2
• Requires more technical skill but potentially creates more natural-looking results 3

Key Differences

Framework Construction

• Brent technique: Uses a simpler framework with less detailed contouring 1
• Nagata technique: Creates a more complex three-dimensional framework with specific attention to the inferior crus and tragal position 3

Number of Surgical Stages

• Brent technique: Traditional four-stage approach 1
• Nagata technique: Two-stage approach, with some modern modifications allowing single-stage reconstruction 3

Ear Elevation Method

• Brent technique: Uses skin graft for elevation in third stage 1
• Nagata technique: Originally uses temporoparietal fascia flap for elevation, though modifications exist using rotation flaps from the mastoid and neck 4

Technical Complexity

• Brent technique: Generally considered technically less demanding 2
• Nagata technique: More technically challenging with a steeper learning curve 2

Outcomes and Complications

Aesthetic Results

• The Nagata technique potentially offers superior aesthetic outcomes due to more detailed framework construction, particularly for the antihelix, tragus, and conchal bowl 3
• The Brent technique may produce less defined contours but with more consistent results 1

Complication Rates

• Multivariate analysis shows the Nagata technique has significantly higher risk for complications (OR 6.14 [95% CI 1.63-23.19]) 2
• Common complications for both techniques include:
  • Framework exposure
  • Cartilage resorption
  • Infection
  • Wire/suture extrusion 5

Patient Selection Factors

• Age considerations: Better outcomes reported when reconstruction is delayed until at least 15 years of age (53% good outcomes vs. 9% in younger patients) 5
• Neither technique shows significant outcome differences based on patient sex or laterality of microtia 2

Recent Modifications and Trends

• Modern approaches have evolved toward single-stage reconstructions modified from the Nagata technique 3
• Technical modifications include:
  • Use of double-armed nylon sutures instead of wire for framework construction
  • Reduced projection of the third layer of the framework in select cases
  • Inclusion of projection blocks to achieve symmetric projection 5, 3
• Some surgeons now avoid the second stage entirely if adequate projection is achieved in the first stage 5

Practical Considerations for Technique Selection

• The Brent technique may be preferred for:

  • Surgeons early in their learning curve
  • Cases where minimizing complications is the priority
  • Patients who can tolerate multiple shorter procedures 2, 1

• The Nagata technique may be preferred for:

  • More experienced surgeons
  • Cases where optimal aesthetic outcome is the priority
  • Patients who prefer fewer surgical stages 3