Abstract (Invited) |
Laser Optoacoustic Imaging System in
Application for Cancer Diagnostics
A.Oraevsky (University of Texas Medical
Branch, Galveston, TX, USA); A.A.Karabutov, V.G.Andreev (Moscow State
University, Moscow, Russia); P.M.Henrichs (LaserSonix Technologies, TX, USA)
e-mail:
aaoraevs@utmb.edu
Principles
of the optoacoustic tomography, current status of development of the Laser
Optoacoustic Imaging System (LOIS) and its applications for cancer detection
and characterization will be reviewed based on results of collaborative efforts
at the University of Texas Medical Branch, LaserSonix Technologies Incorporated
and Moscow State University. The optoacoustic tomography employs laser pulses
for effectively generation of transient pressure in cancerous tissue and
ultrawide-band ultrasonic transducers for sensitive detection of profiles of
optoacoustic signals representing distribution of acoustic sources in tissues.
The laser wavelength can be chosen for optimal tissue contrast and penetration
depth in tissue. The main advantage of LOIS compared with conventional
ultrasound is the enhanced optical contrast between tumors and normal tissue
ranging from 200% to 600%. This contrast is defined primarily by increased
concentration of deoxygenated blood in microcirculation network of cancerous
tissue. Application of two colors of laser pulses matching peaks in optical
absorption of oxy- and deoxy- hemoglobin permits differentiation of aggressive
malignant tumors from benign lesions. Two modes of the optoacoustic detection,
forward mode and backward mode, permit flexibility of the system design for
each human organ. Applications of LOIS for cancer detection in the breast,
prostate and digestive system will be discussed. Methods for optimization of
the system parameters, such as resolution, field of imaging, sensitivity and
accuracy of image reconstruction algorithms will be presented.
Section
: 9