Opto-acoustic transducer for medical applications

Patent · Fri Jan 01 00:00:00 EST 1999

OSTI ID:872480

Benett, William ^[1]; Celliers, Peter ^[2]; Da Silva, Luiz ^[3]; Glinsky, Michael ^[1]; London, Richard ^[4]; Maitland, Duncan ^[1]; Matthews, Dennis ^[5]; Krulevich, Peter ^[6]; Lee, Abraham ^[7]

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1. Livermore, CA
2. Berkeley, CA
3. Danville, CA
4. Orinda, CA
5. Moss Beach, CA
6. Pleasanton, CA
7. Walnut Creek, CA

This invention is an optically activated transducer for generating acoustic vibrations in a biological medium. The transducer is located at the end of a fiber optic which may be located within a catheter. Energy for operating the transducer is provided optically by laser light transmitted through the fiber optic to the transducer. Pulsed laser light is absorbed in the working fluid of the transducer to generate a thermal pressure and consequent adiabatic expansion of the transducer head such that it does work against the ambient medium. The transducer returns to its original state by a process of thermal cooling. The motion of the transducer within the ambient medium couples acoustic energy into the medium. By pulsing the laser at a high repetition rate (which may vary from CW to 100 kHz) an ultrasonic radiation field can be established locally in the medium. This method of producing ultrasonic vibrations can be used in vivo for the treatment of stroke-related conditions in humans, particularly for dissolving thrombus. The catheter may also incorporate anti-thrombolytic drug treatments as an adjunct therapy and it may be operated in conjunction with ultrasonic detection equipment for imaging and feedback control.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• DOE Contract Number: W-7405-ENG-48
• Assignee: Regents of University of California (Oakland, CA)
• Patent Number(s): US 5944687
• OSTI ID: 872480
• Country of Publication: United States
• Language: English

Related Subjects

opto-acoustic
transducer
medical
applications
optically
activated
generating
acoustic
vibrations
biological
medium
located
fiber
optic
catheter
energy
operating
provided
laser
light
transmitted
pulsed
absorbed
fluid
generate
thermal
pressure
consequent
adiabatic
expansion
head
ambient
returns
original
process
cooling
motion
couples
pulsing
repetition
rate
vary
cw
100
khz
ultrasonic
radiation
field
established
locally
method
producing
vivo
treatment
stroke-related
conditions
humans
particularly
dissolving
thrombus
incorporate
anti-thrombolytic
drug
treatments
adjunct
therapy
operated
conjunction
detection
equipment
imaging
feedback
control
optically activated
acoustic transducer
medical applications
repetition rate
fiber optic
laser light
pulsed laser
feedback control
acoustic energy
radiation field
light transmitted
stroke-related conditions
ultrasonic vibrations
acoustic vibrations
ultrasonic detection
detection equipment
acoustic vibration
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