Holography: How the 50,000 pound MRI machine can become“light”
Iron Man would not be Iron Man without JARVIS, Tony Stark’s closest confidant and an entirely holographic information system that’s perfect for picking out tuxedos and defeating alien warlords. Though JARVIS may be a fictional software dreamed up by Marvel’s Cinematic Universe, some individuals interface with holographic technology almost as much as Tony Stark does.
Holography is an extremely interdisciplinary science, relying heavily on math and physics. The basic principles of holography are based on the physical properties of light. As light travels through different media, such as water or a piece of paper, it scatters. Light scattering is the phenomenon that photons, the energetic particles of light, will be displaced in space depending on the medium that they’re traveling through. That is, the light may scatter more or less based on the specific medium. This scattering is the cornerstone of holography. Scattered photons move chaotically and cannot tell us much about an object being observed with light. However, by directing the position and angle of each photon at a certain distance from the light source, a formerly disordered frenzy can be reconstructed into an intelligible image.
Mary Lou Jepsen, founder of Openwater — a startup with a mission to develop more accessible and precise medical imaging technology — combines holographic science with an innovative new computer chip to image human body parts at an unprecedented level of detail. This newfound resolution will make visualizing individual cell bodies in vivo possible on a non-invasive scale.
Jepsen’s revolutionary, customized computer chip provides a sleek and effective method of directing a hologram and collecting the data. The computer chip directs the operations of the holographic technology by pinging ultrasound rays into the body that align photons of red light. When the ultrasound waves interfere with the photons, the photons change color, which can be collected as data before the chip redirects the waves to a new location. The main operational component of the chip is to enable rapid scanning and subsequent de-scattering of light in order to see through flesh and bone. Finally, the data is readily decoded within milliseconds to form an intelligible image. Using these innovative methods, Mary Lou Jepsen is changing the face of modern imaging with holographic science.
Jepsen’s visualization methods are remarkably fast and accessible compared to pre-existing methods, such as EEG, PET, MRI, and fMRI, which may take anywhere between minutes or days to process. For instance, EEG, short for electroencephalography, is used to display brain activity at different physiological states using electrical conduction from certain regions of the brain. The main drawback of EEG is that electrical conductivity may vary from person to person to the degree that it may not even be clear which region of the brain is emitting the signal. EEG data is comprised of signals from nerve throughout an individual’s body — their heart, the movement of their eyes, the expansion of their lungs — as well as from the surrounding environment. All of these overlapping signals constitute “noise” that must be removed from the signal of interest. Furthermore, noise varies between individuals and environments. Therefore, EEG technology presents the significant challenge of separating and making sense of signals accurately.
Another method of neuroimaging, positron emission tomography (PET), involves injecting a radioactive particle, a “tracer,” into the bloodstream. The tracer’s path through the body is tracked by a special detector that can identify where it is at a given moment. PET scans are ideal for identifying general regions of activity, but cannot pinpoint exact locations of activity and require a low-radiation injection. Additionally, PET scans are not a viable method of imaging for pregnant women or diabetics due to the interference of the radioactive tracer with the fetus or with glucose, respectively.
Magnetic resonance imaging, or MRI, uses radio waves to stimulate atomic nuclei and measures the movement of the nuclei to form an image of different brain structures. MRI currently has the best resolution of any other imaging techniques: it can visualize distinct structures in real-time. However, current MRI’s are bulky and expensive. And although MRI has the best resolution to date, it isn’t a reliable imaging method for individuals with implants that may interfere with signal acquisition.
The last of the modern imaging techniques, fMRI, or functional MRI, measures signaling changes in the brain that pertain to blood flow and levels of oxygenated blood. fMRI will display regions where there is more blood flow in “warm” tones, such as red and orange; conversely, it will illustrate regions where there is decreased blood flow with “cool” tones, like blue and purple. A functional MRI requires the same procedure and machinery as a regular MRI and presents the same drawbacks.
Overall, modern imaging techniques permit differential success in visualizing human body parts; none of these methods, however, confer the precision, accuracy, and lack of invasiveness that Mary Lou Jepsen’s approach does.
Jepsen’s technology is precise, fast, and portable. Her intended business model is to implement the computer chips into everyday objects such as belts, hats, or even pillows. The technology would operate at the user’s discretion and would be as easily accessible as changing your belt or putting on a different cap.
The holographic imaging technology pioneered by Jepsen has applications that extend from microbiological to public health-related issues. In a TED Talk she delivered earlier this year, Mary Lou Jepsen explained that her innovation has the ability to kill the bacteria, viruses, or fungi that cause pneumonia. In addition, her technology is capable of detecting the specific type of stroke that has affected an individual so that they may be administered the correct medicine within the shortest amount of time possible. Turning her attention to global public health, Jepsen also pointed out that two-thirds of humanity lack medical imaging. She hopes her technology will give rise to a new age of portable, fast, and efficient imaging devices that will make a profound impact on communities that currently lack the infrastructure necessary to have large, expensive, and high maintenance imaging machines. Lastly, Jepsen alluded to an extraordinarily complex, farther-than-ever-before reaching brain-computer interface system that is facilitated by her extremely precise technology.
The field of technology is continuously growing and expanding in each and every direction. At its intersection with biology, Mary Lou Jepsen has harnessed human and machine intelligence to spawn true innovation.
This article was co-written by Rachel Woody and Rebecca Bair and edited by Jwalin Joshi.
Rachel Woody is a student at the University of California, Berkeley, studying Cognitive Science and Computer Science.
Rebecca Bair is an undergraduate at the University of California, Berkeley studying Neurobiology.
Jwalin Joshi is an undergraduate at the University of California, Berkeley, studying Applied Math and Computer Science.
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