Researchers at MIT have designed a wearable ultrasound device that could allow people to detect early-stage breast cancer tumours. In particular, it could be valuable for patients at high risk of developing breast cancer in between routine mammograms.
The device is a flexible patch that can be attached to a bra. The wearer can then image the breast tissue from different angles by moving an ultrasound tracker along the patch. The researchers have demonstrated that the images that the device can provide have a resolution comparable to that of the ultrasound probes used in medical-imaging centres.
‘We changed the form factor of the ultrasound technology so that it can be used in your home. It’s portable and easy to use, and provides real-time, user-friendly monitoring of breast tissue,’ said Canan Dagdeviren, an associate professor in MIT’s Media Lab.
Dagdeviren drew inspiration for the project from her late aunt, Fatma Caliskanoglu, who was diagnosed with late-stage breast cancer at age 49, despite being screened regularly, and passed away six months later. At her aunt’s bedside, Dagdeviren, then a postdoc at MIT, drew up a rough schematic of a diagnostic device that could be incorporated into a bra and would allow for more frequent screening of individuals at high risk for breast cancer.
Breast tumours that develop in between regularly scheduled mammograms – known as interval cancers – account for 20–30 per cent of all breast cancer cases, and these tumours tend to be more aggressive than those found during routine scans.
‘My goal is to target the people who are most likely to develop interval cancer,’ said Dagdeviren, whose research group specialises in developing wearable electronic devices that conform to the body. ‘With more frequent screening, our goal is to increase the survival rate to up to 98 per cent.’
To make her vision of a diagnostic bra a reality, Dagdeviren designed a miniaturised ultrasound scanner that could allow the user to perform imaging at any time. This scanner is based on the same kind of ultrasound technology used in medical-imaging centres, but incorporates a novel piezoelectric material that allowed the researchers to miniaturise the ultrasound scanner.
To make the device wearable, the researchers designed a flexible, 3D-printed patch that has honeycomb-like openings. Using magnets, this patch can be attached to a bra that has openings that allow the ultrasound scanner to make contact with the skin. The ultrasound scanner fits inside a small tracker that can be moved to six different positions, allowing the entire breast to be imaged. The scanner, which doesn’t require any special expertise to operate, can also be rotated to take images from different angles.
‘This technology provides a fundamental capability in the detection and early diagnosis of breast cancer, which is key to a positive outcome,’ said Anantha Chandrakasan, dean of MIT’s School of Engineering and the Vannevar Bush professor of electrical engineering and computer science. ‘This work will significantly advance ultrasound research and medical device designs, leveraging advances in materials, low-power circuits, AI algorithms and biomedical systems.’
Working with the MIT Center for Clinical and Translational Research, the researchers tested their device on one human subject – a 71-year-old woman with a history of breast cysts. Using the new device, the researchers were able to detect the cysts, which were as small as 0.3 centimetres in diameter – the size of early-stage tumours. They also showed that the device can image tissue at a depth up to eight centimetres.
‘Access to quality and affordable health care is essential for early detection and diagnosis. As a nurse, I have witnessed the negative outcomes of a delayed diagnosis. This technology holds the promise of breaking down the many barriers for early breast cancer detection by providing a more reliable, comfortable and less-intimidating diagnostic,’ said Catherine Ricciardi, nurse director at MIT’s Center for Clinical and Translational Research.
To see the ultrasound images, the researchers currently have to connect their scanner to the same kind of ultrasound machine used in imaging centres. However, they’re now working on a miniaturised version of the imaging system that would be about the size of a smartphone.
‘Breast cancer is the most common cancer among women, and it is treatable when detected early,’ said Tolga Ozmen, a breast cancer surgeon at Massachusetts General Hospital. ‘One of the main obstacles in imaging and early detection is the commute that the women have to make to an imaging centre. This conformable ultrasound patch is a highly promising technology as it eliminates the need for women to travel to an imaging centre.’
The researchers hope to develop a workflow so that once data are gathered from a subject, artificial intelligence can be used to analyse how the images change over time, which could offer more accurate diagnostics than relying on the assessment of a radiologist comparing images taken years apart. They also plan to explore adapting the ultrasound technology to scan other parts of the body.
The research has been published in Science Advances.