Laser and acoustic lens for lithotripsy

Patent · Tue Jan 01 00:00:00 EST 2002

OSTI ID:874928

Visuri, Steven R ^[1]; Makarewicz, Anthony J ^[2]; London, Richard A ^[3]; Benett, William J ^[1]; Krulevitch, Peter ^[4]; Da Silva, Luiz B ^[4]

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1. Livermore, CA
2. San Ramon, CA
3. Orinda, CA
4. Pleasanton, CA

An acoustic focusing device whose acoustic waves are generated by laser radiation through an optical fiber. The acoustic energy is capable of efficient destruction of renal and biliary calculi and deliverable to the site of the calculi via an endoscopic procedure. The device includes a transducer tip attached to the distal end of an optical fiber through which laser energy is directed. The transducer tip encapsulates an exogenous absorbing dye. Under proper irradiation conditions (high absorbed energy density, short pulse duration) a stress wave is produced via thermoelastic expansion of the absorber for the destruction of the calculi. The transducer tip can be configured into an acoustic lens such that the transmitted acoustic wave is shaped or focused. Also, compressive stress waves can be reflected off a high density/low density interface to invert the compressive wave into a tensile stress wave, and tensile stresses may be more effective in some instances in disrupting material as most materials are weaker in tension than compression. Estimations indicate that stress amplitudes provided by this device can be magnified more than 100 times, greatly improving the efficiency of optical energy for targeted material destruction.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• DOE Contract Number: W-7405-ENG-48
• Assignee: The Regents of the University of California (Oakland, CA)
• Patent Number(s): US 6491685
• OSTI ID: 874928
• Country of Publication: United States
• Language: English

Related Subjects

laser
acoustic
lens
lithotripsy
focusing
device
waves
generated
radiation
optical
fiber
energy
capable
efficient
destruction
renal
biliary
calculi
deliverable
site
via
endoscopic
procedure
transducer
tip
attached
distal
directed
encapsulates
exogenous
absorbing
dye
proper
irradiation
conditions
absorbed
density
pulse
duration
stress
wave
produced
thermoelastic
expansion
absorber
configured
transmitted
shaped
focused
compressive
reflected
densitylow
interface
invert
tensile
stresses
effective
instances
disrupting
material
materials
weaker
tension
compression
estimations
indicate
amplitudes
provided
magnified
100
times
greatly
improving
efficiency
targeted
optical fiber
laser radiation
acoustic wave
compressive stress
/606/