UBC researcher Carlos Gerardo shows new ultrasound transducer. Credit: Clare Kiernan, University of British Columbia

A team from the University of British Columbia has created a portable, wearable ultrasound transducer that could reduce the cost of ultrasound scanners down to about $100.

Conventional ultrasound scanners utilize piezoelectric crystals that are able to create images of the inside of the body and send them to a computer to create sonograms.

However, in the new transducer, the scientists switched the piezoelectric crystals out with small vibrating drums made from a polymer resin—polymer capacitive micro-machined ultrasound transducers (polyCMUTs), which are less expensive to manufacture.

“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,” study lead author Carlos Gerardo, a PhD candidate in electrical and computer engineering at UBC, said in a statement. “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.”

The device features low operational voltage and are highly sensitive, partially due to a pre-biasing condition on the membrane. The fabrication used simple equipment with a reduced number of fabrication steps needed.

The sonograms it produced were at least as sharp and in some cases more detailed than traditional sonograms produced with piezoelectric transducers.

“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,” co-author Edmond Cretu, a professor of electrical and computer engineering, said in a statement. “And unlike rigid ultrasound probes, our 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.”

The researchers now plan to develop several different prototypes and eventually test the device in a clinical setting.

“You could miniaturize these transducers and use them to look inside your arteries and veins,” co-author Robert Rohling, a professor of electrical and computer engineering, said in a statement. “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.”

According to the study, the forecasted growth for the ultrasound market went from $4.6 billion in 2012 to almost $7 billion by 2019.

The study was published in Microsystems & Nanoengineering.