The study was led by Dr. Maysam Chamanzar,
Ph.D, who is an Assistant Professor of Electrical and Computer Engineering at
Carnegie Mellon University, Pittsburgh, Pennsylvania, USA. The study was
conducted by Matteo Giuseppe Scopelliti, who is a Ph.D candidate at Carnegie
Mellon University's College of Engineering.
‘Ultrasound-assisted optical imaging technology has been developed, which could replace invasive procedures like endoscopy. The technology is non-invasive, painless and patient-friendly and could revolutionize the medical imaging field.
’
The study has been
published in the journal
Light: Science
& Applications, which is a Springer Nature publication.
What are the Disadvantages of Endoscopic
Imaging?
The main
disadvantage of endoscopic imaging is that it is highly invasive. In this
procedure, an endoscope consisting of a thin tube or catheter, fitted with a
miniature camera and biopsy instruments need to be inserted deep within the
body cavities for establishing a diagnosis. This procedure is very awkward and
uncomfortable, making it unpopular among patients.
What is Novel about the New Imaging Technology?
The novelty of the
new imaging technology lies in the fact that it permits visualization of deep
tissues within the body, which cannot be visualized by light. Since the
technique is non-invasive, it is essentially
a painless procedure, which makes it
patient-friendly as well as easy to
use. Moreover, by using ultrasound, a 'virtual lens' is created within the
body, which alleviates the need for implantation of a 'physical lens,' thereby
making the procedure much less cumbersome and
more user-friendly. This novel
technology has allowed the visualization of deeply situated tissues, which has
never before been possible using non-invasive techniques.
What is the Underlying Mechanism Involved?
It is an
established fact that biological tissues block light waves, especially those
falling within the visual range of the spectrum. Consequently, currently
available imaging techniques cannot use visible light to visualize deep-seated
tissues within the body.
The new
technology, on the other hand, uses ultrasound waves, which are capable of
compression and rarefaction of the medium through which they pass. This alters
the speed of light, which travels slower in compressed regions and faster in the rarefied
regions. This results in the creation of a 'virtual lens' that focuses light
within the tissue, allowing greater transparency.
The focusing
accuracy of this 'virtual lens' can be fine-tuned by altering the parameters of
the ultrasound waves, allowing visualization of tissues located at different
depths within the body. Moreover, the 'virtual lens' can be moved about without
disturbing the medium by controlling the properties of the ultrasound waves
from outside, allowing visualization non-invasively.
"Being able to relay images from organs such as the brain without the
need to insert physical optical components will provide an important
alternative to implanting invasive endoscopes in the body," says Chamanzar.
"We used ultrasound waves to sculpt a
virtual optical relay lens within a given target medium, which, for example,
can be biological tissue. Therefore, the tissue is turned into a lens that
helps us capture and relay the images of deeper structures. This method can
revolutionize the field of biomedical imaging." What are the Applications of the New Technology?
Some of the potential applications of this new technology
are listed below:
- Brain tissue imaging for monitoring brain activity
- Dermal imaging for diagnosing skin diseases
- Cancer imaging for detecting malignant tumors
- Optical imaging in computer vision
- Metrology (the science of measurement)
- Industrial imaging applications at the micron scale
What are the Future Prospects?
Ultrasound-assisted
optical imaging technique appears to have a bright future ahead. The technology
can be used as a handheld device or a wearable skin patch, depending on which
organ is being imaged. This will enable the physician to instantly visualize
what's going on inside the body, without having to do an endoscopy. Indeed,
endoscopy
may even be replaced by this new technology in the future. Moreover, this
new acousto-optic technology could be used for research purposes involving
brain imaging to better understand conditions such as
Parkinson's disease, as well as psychiatric and
other brain disorders.
Concluding Remarks
"What distinguishes our work from conventional acousto-optic
methods is that we are using the target medium itself, which can be biological
tissue, to affect light as it propagates through the medium," says Chamanzar.
"This in situ interaction provides
opportunities to counterbalance the non-idealities that disturb the trajectory
of light."
Scopelliti
concludes:
"Turbid media have always been
considered obstacles for optical imaging." He adds:
"But we have shown that such media can be converted to allies to help
light reach the desired target. When we activate ultrasound with the proper
pattern, the turbid medium becomes immediately transparent. It is exciting to
think about the potential impact of this method on a wide range of fields, from
biomedical applications to computer vision."
The research team is
optimistic that the new imaging technology could be available for clinical use
within a matter of five years.
Reference : - Breakthrough in optical endoscopy using ultrasound - (https://engineering.cmu.edu/news-events/news/2019/07/16-chamanzar-nature.html)
Source: Medindia