'Low-cost wearable ultrasound scanner designed'

Scientists say they have designed a new portable, wearable ultrasound scanner that can be powered by a smartphone, and may cost as little as USD 100.

Conventional ultrasound scanners use piezoelectric crystals to create images of the inside of the body and send them to a computer to create sonograms.

Piezoelectric effect is the ability of certain materials to generate an electric charge in response to applied mechanical stress.

Researchers from the University of British Columbia (UBC) in Canada replaced the piezoelectric crystals with tiny vibrating drums.

These drums are made of polymer resin, called polyCMUTs (polymer capacitive micro-machined ultrasound transducers), which are cheaper to manufacture, they said.

"Transducer drums have typically been made out of rigid silicon materials that require costly, environment-controlled manufacturing processes, and this has hampered their use in ultrasound," said Carlos Gerardo from UBC.

"By using polymer resin, we were able to produce polyCMUTs in fewer fabrication steps, using a minimum amount of equipment, resulting in significant cost savings," said Gerardo, who led the study published in the journal Nature Microsystems & Nanoengineering.

Sonograms produced by the device were as sharp as or even more detailed than traditional sonograms produced by piezoelectric transducers, said Edmond Cretu, a professor at UBC.

"Since our transducer needs just 10 volts to operate, it can be powered by a smartphone, making it suitable for use in remote or low-power locations," he added.

Unlike rigid ultrasound probes, the transducer has the potential to be built into a flexible material that can be wrapped around the body for easier scanning and more detailed views -- without dramatically increasing costs, resaerchers said.

In the US, conventional ultrasound scanners currently cost thousands of dollars.

According to Robert Rohling, a professor at UBC, the next step in the research is to develop a wide range of prototypes and eventually test their device in clinical applications.

"You could miniaturise these transducers and use them to look inside your arteries and veins.

"You could stick them on your chest and do live continuous monitoring of your heart in your daily life. It opens up so many different possibilities," said Rohling.