Opto-acoustic transducer for medical applications

Patent · Thu Dec 31 23:00:00 EST 1998

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
• 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

/604/606/
100
absorbed
acoustic
acoustic energy
acoustic transducer
acoustic vibration
acoustic vibrations
activated
adiabatic
adjunct
ambient
anti-thrombolytic
applications
biological
catheter
conditions
conjunction
consequent
control
cooling
couples
cw
detection
detection equipment
dissolving
drug
energy
equipment
established
expansion
feedback
feedback control
fiber
fiber optic
field
fluid
generate
generating
head
humans
imaging
incorporate
khz
laser
laser light
light
light transmitted
locally
located
medical
medical applications
medium
method
motion
operated
operating
optic
optically
optically activated
opto-acoustic
original
particularly
pressure
process
producing
provided
pulsed
pulsed laser
pulsing
radiation
radiation field
rate
repetition
repetition rate
returns
stroke-related
stroke-related conditions
therapy
thermal
thrombus
transducer
transmitted
treatment
treatments
ultrasonic
ultrasonic detection
ultrasonic vibrations
vary
vibrations
vivo