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Applied Physics B

, Volume 42, Issue 2, pp 73–78 | Cite as

Optical studies of pulsed-laser fragmentation of biliary calculi

  • P. Teng
  • N. S. Nishioka
  • R. Rox Anderson
  • T. F. Deutsch
Contributed Papers

Abstract

The fragmentation of gallstones and kidney stones using pulsed visible laser radiation has recently been demonstrated; however, the fragmentation mechanism is not well understood. The temporal and spectral characteristics of the bright flash of light accompanying fragmentation of gallstones were studied using 0.8 and 360-μs-long, 690-nm-wavelength, dye-laser pulses. Time-resolved visible emission spectra show a broad continuum upon which line spectra are superimposed. The continuum emission is due to free-free and free-bound electron transitions indicative of a plasma and the line spectra are due to neutral and ionized calcium. Initiation of this plasma is fluence rather than intensity dependent. A model is proposed in which laser energy is coupled to the plasma, which then impulsively expands, generating intense acoustic transients which fracture the stone.

PACS

52 87 

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Copyright information

© Springer-Verlag 1987

Authors and Affiliations

  • P. Teng
    • 1
    • 2
  • N. S. Nishioka
    • 1
    • 2
  • R. Rox Anderson
    • 1
    • 2
  • T. F. Deutsch
    • 1
    • 2
  1. 1.Department of Dermatology and Medical Service (Gastrointestinal Unit), Wellman Research LaboratoryMassachusetts General HospitalBostonUSA
  2. 2.Departments of Dermatology and MedicineHarvard Medical SchoolBostonUSA

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