Engineers at Washington University in St. Louis adapted a small ultrasound prove to interface with a Microsoft Windows mobile smartphone. Although the screen may be too small to diagnose anything properly, it is thought the concept will be used to scan a patient away from the clinic, with the data wirelessly sent to physicians with large screen computers for evaluation.
In order to make commercial USB ultrasound probes work with smartphones, the researchers had to optimize every aspect of probe design and operation, from power consumption and data transfer rate to image formation algorithms. As a result, it is now possible to build smartphone-compatible USB ultrasound probes for imaging the kidney, liver, bladder and eyes, endocavity probes for prostate and uterine screenings and biopsies, and vascular probes for imaging veins and arteries for starting IVs and central lines.
“You can carry around a probe and cell phone and image on the fly now,” said Richard [William D. Richard, Ph.D., WUSTL associate professor of computer science and engineering]. “Imagine having these smartphones in ambulances and emergency rooms. On a larger scale, this kind of cell phone is a complete computer that runs Windows. It could become the essential computer of the Developing World, where trained medical personnel are scarce, but most of the population, as much as 90 percent, have access to a cell phone tower.”
Zar [David Zar, research associate in computer science and engineering] said the vision of the new system is to train people in remote areas of the developing world on the basics of gathering data with the phones and sending it to a centralized unit many miles, or half a world away where specialists can analyze the image and make a diagnosis. Zar wrote the phone software and firmware for the probes; Richard came up with the low-power probe electronics design. He began working on ultrasound system designs 25 years ago, and in that span he has shrunk the electronics from cabinet-sized to a tiny circuit board one inch by three inches. A typical, portable ultrasound device may cost as much as $30,000. Some of these USB-based probes sell for less than $2,000 with the goal of a price tag as low as $500.
Another promising application is for caregivers of patients with Duchene’s Muscular Dystrophy. A degenerative disease that often strikes young boys and robs them of their lives by their late 20s, DMD is a degenerative disease for which there is no cure. The leading treatment to slow its progression is a daily dose of steroids. Patients often experience some side effects from steroids, which are dose related. These side effects include behavioral problems and weight gain. Researchers now know that physical changes in muscle tissue can indicate the efficacy of the steroids. Measuring these changes in muscle can be accomplished with ultrasound and may allow researchers to optimize steroid dosing to maximize efficacy while minimizing side effects.
“The idea is that caregivers, who otherwise have to transport a young person, often wheelchair bound, to a hospital or clinic on a regular basis for examination, can be trained to do ultrasound to track muscle condition,” Zar said. “This could lower the dosage to the least effective amount to further increase quality of life of the patient and the caregiver and hopefully extend life. We’re really excited about this application. The caregiver would only have to do a one-minute scan, transfer the data captured to the clinic, and the results would come back to the caregiver. A group at the WUSTL Medical School studying Duchene’s Muscular Dystrophy is very interested in our devices and hopes they can incorporate them into their research plans.”