technology
Lighting up the Brain and
Breast without Radiation
Michael J. Feeney
Recently, a British study confirmed again
the dangers associated with CT scans
with children: “Children under the age
of 15 who receive multiple CT scans
are three times more likely to develop
a brain tumor or leukemia.” 1 And, in
2009, the Archives of Internal Medicine
announced: “Radiation from CT scans
done in 2007 will kill 15,000 Americans
while also causing 29,000 cancers.” 2
This has come at a time when traumatic brain injuries (TBI) are gaining
national attention due to the recent suicides of NFL players Junior Seau and
David Duerson. TBI is the leading cause
of death for Americans under age 45. It
is the signature wound of the Iraq and
Afghanistan conflicts and, when NHL
player Bob Probert died suddenly at the
age of 45, scientists at Boston University
discovered that the constant blows to his
head caused a degenerative brain disease
called chronic traumatic encephalopathy.
A new patented technology, Optical
Ultrasound Tomography®, offers some
hope to radiologists and other caregivers. It is a novel photoacoustic imaging
approach that will “light up” the brain
and breast tissue without radiation. The
scientists who invented Optical Ultrasound Tomography® hope to give radiologists the ability to view relatively small
structures never before able to be seen.
Optical Ultrasound Tomography® is
also referred to as “non-contact” ultrasound or “non-contact” photoacoustic
imaging. Once the tissue is lit up, the
technology will provide images of tiny
The images obtained from photoacoustic imaging combine
near infrared wavelengths and ultrasound in one modality
in order to obtain high resolution and high contrast images.
structures within the body, functional
information about tissues and cells, and
levels of oxygen in the blood.
Photoacoustic imaging has become
one of the most explored emerging tissue
diagnostic technologies due to its great
potential as demonstrated in multiple
preclinical and, more recently, clinical
in vivo imaging studies. Photoacoustic
imaging is a breakthrough in imaging
technology, as it is based on functional
and not anatomical imaging. The images
obtained from photoacoustic imaging
combine near infrared wavelengths and
ultrasound in one modality in order to
obtain high resolution and high contrast
images.
Photoacoustic imaging is based on
the detection of acoustic waves induced
in tissue by the absorption of a short
laser pulse. Photoacoustic imaging combines the contrast of optical absorption
with the high spatial resolution provided
by ultrasound transducers. But, photoacoustic imaging requires ultrasound
receivers to be in contact with the human
tissue. Since ultrasound waves cannot
successfully propagate though thick bone
or the cranium and deliver high resolution images, neither standard ultrasound
nor photoacoustic imaging can be used
to detect bleeding in the brain and TBI.
Optical Ultrasound Tomography®
detects the ultrasound waves as light
prior to their exit from the tissue or
brain. Thus, there is no need for direct
contact with the human skin or skull.
Optical Ultrasound Tomography® non-invasively measures pressure waves created by a TBI, cerebral injury or cerebral
swelling. When there is a TBI, malignant
tumor, hematoma, hemorrhage, or cerebral edema, the brain cannot quickly
compensate for the increase in the contents of the intra-cranial area, or the
intra-spinal area, in a short period of
time.
A hemorrhagic collection (either
subdural or epidural) in the cranium
(skull) will be in a confined space. An
expanding collection in a confined space
will develop increased pressure, as it fills
the space with more and more blood.
That increase in pressure will lead to an
increase in size and mass effect on the
brain.
Optical Ultrasound Tomography®
will also calculate the concentration of
oxygen carrying blood cells (or hemoglobin) in each lesion. A high density of
hemoglobin in a tumor is known to be
highly correlated with malignancy. Early
stage invasive cancers have a two-fold
higher total hemoglobin concentration
