Laser-assisted fixation of a nitinol stapes prosthesis

Lasers Surg Med. 2018 Feb;50(2):153-157. doi: 10.1002/lsm.22738. Epub 2017 Nov 2.

Abstract

Background and objective: Otosclerosis is an inner ear bone disease characterized by fixation of the stapes and consequently progressive hearing loss. One treatment option is the surgical replacement of the stapes by a prosthesis. When so called "smart materials" like nitinol are used, prosthesis fixation can be performed using a laser without manual crimping on the incus. However, specific laser-prosthesis interactions have not been described yet. The aim of the present study was to elucidate the thermo-mechanical properties of the NiTiBOND® prosthesis as a basis for handling instructions for laser-assisted prosthesis fixation.

Study design and materials and methods: Closure of the NiTiBOND® prosthesis was induced ex vivo by either a diode laser emitting at λ = 940 nm or a CO2 laser (λ = 10,600 nm). Total energy for closure was determined. Suitable laser parameters (pulse duration, power per pulse, distance between tip of the laser fiber and prosthesis) were assessed. Specific laser-prosthesis interactions were recorded.

Results: Especially the diode laser was found to be an appropriate energy source. A total energy deposit of 60 mJ by pulses in near contact application was found to be sufficient for prosthesis closure ex vivo. Energy should be transmitted through a laser fiber equipollent to the prosthesis band diameter. Specific deformation characteristics due to the zonal prosthesis composition have to be taken into account.

Conclusion: NiTiBOND® stapes prosthesis can be closed by very little energy when appropriate energy sources like diode lasers are used, suggesting a relatively safe application in vivo. Lasers Surg. Med. 50:153-157, 2018. © 2017 Wiley Periodicals, Inc.

Keywords: CO2 laser; NiTiBOND®; diode laser; prosthesis; smart materials; stapes surgery.

MeSH terms

  • Alloys
  • Equipment Design
  • In Vitro Techniques
  • Laser Therapy / methods*
  • Lasers, Semiconductor
  • Materials Testing
  • Ossicular Prosthesis*
  • Otosclerosis / surgery*
  • Prosthesis Design
  • Prosthesis Implantation / methods*
  • Stapes Surgery / methods*

Substances

  • Alloys
  • nitinol