03-08-2022 | By Robin Mitchell

Recently, researchers from MIT have demonstrated a paper-thin sensor that can be stuck onto skin and generate an internal image of vessels and other structures. What challenges do imaging technologies face, what did the researchers develop, and how could it transform the medical industry?

What challenges do imaging technologies face?

When trying to diagnose a patient, doctors have numerous tools at their disposal including heart rate monitors, oxygen detectors, blood tests, and internal imaging systems such as MRI. While it would be convenient for patients to be given the full work every time they visit their doctor, the practical reality of healthcare is that the large expenses involved with complex testing procedures often see doctors start with cheaper tests before moving on to more advanced technology. 

Even though imaging technologies such as MRI and CAT scans can provide invaluable amounts of data, their high cost makes them difficult to provide (especially for government-run services such as the NHS). Worse, some imaging technologies can be potentially harmful in their use, and as such doctors will refrain from using them. One such imaging technology would be CAT scans; the use of powerful x-rays that spin around the patient and image from all angles creates accurate 3D internal models, but at the cost of exposure to ionising radiation.

MRI is a technology that doesn’t use ionizing radiation and as such can be used as many times as needed. However, MRIs are not without their faults with one common issue being claustrophobia. As the scanner requires to be in close proximity to the imaging source, MRIs can be thought of as tight cylinders that produce loud banging noises from the intense magnetic field, and this is something that many patients prefer to avoid. Additionally, MRI machines require the patient to be perfectly still during the entire scan (which can be over 30 minutes).

Finally, imaging technologies such as ultrasound do provide patients with a lower cost option for internal non-invasive scans, but the use of lower frequencies for increased depth imaging results in lower resolution images. As such, they are ideal for viewing a foetus, but not so able to identify small tumours deep inside of tissue.

Researchers create stamp-size sensor able to produce internal images

Recently, researchers from MIT have developed a new sensor that is able to take internal body images non-invasively that fits on a sticker the size of a typical postage stamp. The sensor, which measures 2x3cm, is directly stuck onto skin in the area of interest and is able to identify numerous internal body structures such as blood vessels, growths, and organs.

Images are taken with the use of ultrasound transmitted generated by a ridged piezoelectric probe array that is bonded to the skin with he use of a hydrogel elastomer. Unlike traditional ultrasound imaging devices that require a large probe moved around a target area, multiple sensor patches can be attached to the body simultaneously and used to produce constant real-time images.

According to the researchers, their sensors were able to produce images continuously after 48 hours of use and believe that the use of such sensors could help doctors better understand patient recovery and diagnoses. However, the sensors currently require the patient to be hooked up to machinery via cables and as such are determining new methods to make the sensors wireless.

How could such sensors transform the medical industry?

High-resolution imaging technologies are needed to make informed diagnoses of patients and better understand the internal structure of the body. But this high resolution also makes such technology expensive which is why it is only used when necessary and rarely used for general check-ups.

But while high-resolution is ideal for diagnosis, low-resolution low-cost systems can be ideal for long-term monitoring that looks for changes in biodata. Such changes can indicate potential issues whether it is early stages of cancer, diabetes, or heart disease, and small changes that are detected can then be referred to a doctor who can then run the full suite of tests. 

If the sensors demonstrated by the MIT researchers prove to be practical, it could open up the industry to all kinds of new technologies and healthcare including post-op monitoring of internal vessels and organs, predictive healthcare, and general wellbeing. 


By Robin Mitchell

Robin Mitchell is an electronic engineer who has been involved in electronics since the age of 13. After completing a BEng at the University of Warwick, Robin moved into the field of online content creation, developing articles, news pieces, and projects aimed at professionals and makers alike. Currently, Robin runs a small electronics business, MitchElectronics, which produces educational kits and resources.