[Bone ablation using ultrashort laser pulses. A new technique for middle ear surgery]

Area of Science:

• Otolaryngology and surgical technology.
• Biomedical optics and laser-tissue interactions.

Context:

• Conventional laser systems (CO2, argon, KTP, erbium) used in tympanic cavity surgery present limitations such as heat generation and acoustic load.
• A novel femtosecond laser system was investigated to overcome these limitations for middle ear applications.

Purpose:

• To evaluate the ablation characteristics of a femtosecond laser on human ossicles and porcine compact bone.
• To determine the threshold energy, ablation ratio, and thermal effects of femtosecond laser application.
• To assess the precision and quality of perforations created by the femtosecond laser.

Summary:

• Femtosecond laser ablation requires lower threshold energy (<1 J/cm²) compared to conventional lasers, with minimal thermal damage to surrounding bone tissue due to ultra-short pulse durations (180 fs).
• Histological and scanning electron microscopy analyses confirmed high precision, with incisions and drillings accurate to the micrometer level.
• The femtosecond laser demonstrated efficient, touch-free operation with reduced side effects.

Impact:

• The femtosecond laser emerges as a promising surgical tool for middle ear procedures, offering enhanced handling of bony structures like the incus and stapes footplate.
• Potential applications include improved coupling for implantable hearing aids and ossicular chain reconstruction prostheses.
• This technology could lead to safer and more effective surgical interventions in otology.