Scattering properties and femtosecond laser ablation thresholds of human and canine vocal folds at 776-nm wavelength

Liam Andrus, I-Fan T Mau, Adela Ben-Yakar

Research output: Contribution to journalArticle


Ultrafast laser ablation may provide a treatment for vocal fold (VF) scarring. Optical properties of VFs must be known prior to clinical implementation to select appropriate laser surgery conditions. We present scattering lengths of epithelium ℓs  ,  ep, superficial lamina propria ℓs  ,  SLP, and ablation thresholds <italic>F</italic>th of human and canine VF tissues. Our experimental approach involves an image-guided, laser-ablation-based method that allows for simultaneous determination of ℓs and <italic>F</italic>th in these multilayered tissues. Studying eight canine samples, we found ℓs  ,  ep  =  75.3  ±  5.7  μm, ℓs  ,  SLP  =  26.1  ±  1.2  μm, <italic>F</italic>th  ,  ep  =  1.58  ±  0.06  J  /  cm2, and <italic>F</italic>th  ,  SLP  =  1.55  ±  0.17  J  /  cm2. Studying five human samples, we found ℓs  ,  ep  =  42.8  ±  3.3  μm and <italic>F</italic>th  ,  ep  =  1.66  ±  0.10  J  /  cm2. We studied the effects of cumulative pulse overlap on ablation threshold and found no significant variations beyond 12 overlapping pulses. Interestingly, our studies about the effect of sample storage on the scattering properties of porcine VF show a 60% increase in ℓs  ,  ep for fresh porcine VF when compared to the same sample stored in isotonic solution. These results provide guidelines for clinical implementation by enabling selection of optimal laser surgery parameters for subsurface ablation of VF tissues.

Original languageEnglish (US)
Pages (from-to)1-7
Number of pages7
JournalJournal of biomedical optics
Issue number8
Publication statusPublished - Aug 1 2019



  • scattering measurements
  • tissue ablation, ultrafast lasers
  • ultrafast laser surgery
  • vocal folds
  • vocal folds scarring

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Atomic and Molecular Physics, and Optics
  • Biomedical Engineering

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