
The new system was developed by a CSAIL group led by Professor Dina Katabi (pictured)
Photo: Simon Simard
CSAIL wireless system suggests future where doctors could implant sensors to track tumors or even dispense drugs.
Investigating inside the human body often requires cutting open a patient or swallowing long tubes with built-in cameras. But what if physicians could get a better glimpse in a less expensive, invasive, and time-consuming manner?
A team from MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) led by Professor Dina Katabi is working on doing exactly that with an “in-body GPS” system dubbed ReMix. The new method can pinpoint the location of ingestible implants inside the body using low-power wireless signals. These implants could be used as tiny tracking devices on shifting tumors to help monitor their slight movements.
In animal tests, the team demonstrated that they can track the implants with centimeter-level accuracy. The team says that, one day, similar implants could be used to deliver drugs to specific regions in the body.
ReMix was developed in collaboration with researchers from Massachusetts General Hospital (MGH). The team describes the system in a paper that’s being presented at this week’s Association for Computing Machinery’s Special Interest Group on Data Communications (SIGCOMM) conference in Budapest, Hungary.
Tracking inside the body
To test ReMix, Katabi’s group first implanted a small marker in animal tissues. To track its movement, the researchers used a wireless device that reflects radio signals off the patient. This was based on a wireless technology that the researchers previously demonstrated to detect heart rate, breathing, and movement. A special algorithm then uses that signal to pinpoint the exact location of the marker.
Interestingly, the marker inside the body does not need to transmit any wireless signal. It simply reflects the signal transmitted by the wireless device outside the body. Therefore, it doesn’t need a battery or any other external source of energy.
A key challenge in using wireless signals in this way is the many competing reflections that bounce off a person’s body. In fact, the signals that reflect off a person’s skin are actually 100 million times more powerful than the signals of the metal marker itself.
To overcome this, the team designed an approach that essentially separates the interfering skin signals from the ones they’re trying to measure. They did this using a small semiconductor device, called a “diode,” that mixes signals together so the team can then filter out the skin-related signals. For example, if the skin reflects at frequencies of F1 and F2, the diode creates new combinations of those frequencies, such as F1-F2 and F1+F2. When all of the signals reflect back to the system, the system only picks up the combined frequencies, filtering out the original frequencies that came from the patient’s skin.
One potential application for ReMix is in proton therapy, a type of cancer treatment that involves bombarding tumors with beams of magnet-controlled protons. The approach allows doctors to prescribe higher doses of radiation, but requires a very high degree of precision, which means that it’s usually limited to only certain cancers.
Its success hinges on something that’s actually quite unreliable: a tumor staying exactly where it is during the radiation process. If a tumor moves, then healthy areas could be exposed to the radiation. But with a small marker like ReMix’s, doctors could better determine the location of a tumor in real-time and either pause the treatment or steer the beam into the right position. (To be clear, ReMix is not yet accurate enough to be used in clinical settings. Katabi says a margin of error closer to a couple of millimeters would be necessary for actual implementation.)
“The ability to continuously sense inside the human body has largely been a distant dream,” says Romit Roy Choudhury, a professor of electrical engineering and computer science at the University of Illinois, who was not involved in the research. “One of the roadblocks has been wireless communication to a device and its continuous localization. ReMix makes a leap in this direction by showing that the wireless component of implantable devices may no longer be the bottleneck.”
Looking ahead
There are still many ongoing challenges for improving ReMix. The team next hopes to combine the wireless data with medical data, such as that from magnetic resonance imaging (MRI) scans, to further improve the system’s accuracy. In addition, the team will continue to reassess the algorithm and the various tradeoffs needed to account for the complexity of different bodies.
“We want a model that’s technically feasible, while still complex enough to accurately represent the human body,” says MIT PhD student Deepak Vasisht, lead author on the new paper. “If we want to use this technology on actual cancer patients one day, it will have to come from better modeling a person’s physical structure.”
The researchers say that such systems could help enable more widespread adoption of proton therapy centers. Today, there are only about 100 centers globally.
“One reason that [proton therapy] is so expensive is because of the cost of installing the hardware,” Vasisht says. “If these systems can encourage more applications of the technology, there will be more demand, which will mean more therapy centers, and lower prices for patients.”
Learn more: A “GPS for inside your body”
The Latest on: In-body GPS
via Google News
The Latest on: In-body GPS
- 3 research-backed resolutions for improving visual communication in 2021on January 12, 2021 at 2:51 pm
It's time for marketers to set and implement content resolutions for 2021 – starting with visual content. Petra O’Halloran outlines what consumers will respond to when it comes to visual communication ...
- OpenGate to buy Solvay’s amphoteric surfactant manufacturing businesson January 5, 2021 at 8:46 am
The Business is a key player in surfactants, with a focus on the production of amphoterics primarily utilized in body care, hair care, and home care products. Approximately 175 employees are part ...
- Today’s Apple deals feature the latest M1 Mac mini and moreon December 29, 2020 at 11:00 pm
GPS-only version with a Space Gray Aluminum Case with a Black Sport Band for just under $370, meaning you save $39. We have eight deals on fitness apps that will help you stay healthy in body and ...
- Taser- and body-camera maker Axon Enterprise wants to change policing with its productson December 29, 2020 at 2:52 pm
The company in August introduced its Respond cloud-based communication, dispatch, GPS and camera system ... sparked interest in body cameras worn by police, with an Obama administration task ...
- What are the best cheap DSLRson December 24, 2020 at 2:55 am
Built-in GPS tags the locations where you capture images in case you ... the K-1 MkII is one of the few DSLRs to include a 5-axis In Body Image Stabilisation system, which will help keep shots sharp, ...
- 'Stay fat rather than Atkins'on December 23, 2020 at 3:59 pm
More than one in four GPs would advise a patient to stay obese rather than go on the controversial Atkins diet, a new survey reveals. Concerns about the long-term effects on health of the trendy ...
- GPs 'failed to carry out Shipman checks'on December 22, 2020 at 4:00 pm
The GPs, who all worked in surgeries close to Shipman's practices, regularly counter-signed cremation forms filled out by the murderer and stand accused of failing to make sufficient inquiries ...
- How to remain undetected in Welcome to America, Comrade gig – Cyberpunk 2077on December 9, 2020 at 3:16 pm
In Cyberpunk 2077, you’ll receive a gig to act as an agent saboteur and place a GPS tracker on Mikhail Akulov ... only if you have six points in body. If you do not, jumping over the container ...
- Dual-Visionon December 7, 2020 at 4:00 pm
Speed, direction, GPS coordinates, G-shock sensing accelerometer, speed and panic event marking with Google map layovers are all available with up to 14 hours of continuous recording on a ...
- The best way to win a horse race? Mathematicians may have the answeron December 2, 2020 at 11:26 am
GPS data from horse races at the Chantilly track ... successful,” he says—and not just because horses vary so much in body size and aerobic capacity: The models cannot account for the horse ...
via Bing News