Needle electrode-based electromechanical reshaping of cartilage.

Area of Science:

• Biomedical Engineering
• Regenerative Medicine
• Tissue Engineering

Background:

• Traditional cartilage reshaping relies on surgical methods.
• Electromechanical reshaping (EMR) offers a non-surgical alternative.
• Previous EMR required surface electrodes, limiting its application.

Purpose of the Study:

• To assess the feasibility of using needle electrodes for EMR of facial cartilage.
• To investigate the relationship between electrode configuration, voltage, and application time on cartilage shape change.
• To evaluate cell viability post-EMR.

Main Methods:

• Rabbit nasal septal cartilage was bent and subjected to varying needle electrode configurations, voltages (0-7.5V), and application times (1-9 min).
• Shape change was quantified by retained bend angle; current and temperature were monitored.
• Ex vivo reshaping of rabbit and pig ears was performed using optimized settings.
• Cell viability was assessed using live/dead assays and confocal microscopy.

Main Results:

• Cartilage reshaping increased with higher voltage and longer application times.
• Negligible heat generation (<1°C) was observed up to 6V.
• Significant reshaping occurred at and above 5V with a 2-minute application time.
• Plateau in reshaping was observed above 5 minutes of application time at 6V.

Conclusions:

• Needle electrode EMR is effective for reshaping cartilage grafts and intact ears.
• The procedure results in negligible temperature elevation and spatially limited cell injury.
• Optimized parameters allow for controlled and efficient cartilage modification.