A new ultrasound device could make it easier to detect a potentially life-threatening condition that is common in soldiers with blast-related brain injuries and patients who survive aneurysms.
The condition, called cerebral vasospasm, occurs when blood vessels suddenly constrict. The effect is like squeezing a garden hose: the velocity inside the artery builds as pressure grows, and less blood flows to the brain. The condition can develop several days after an initial injury, and is currently detected using ultrasound, which requires a trained technician to find the relevant blood vessels and hold the ultrasound beam in place.
PhysioSonics, based in Bellevue, Washington, has developed a monitor that makes this process automatic, eliminating the need for a technician. The company is adapting the product for military use, and hopes to expand it to also detect a potentially dangerous buildup of pressure inside the head.
The company’s monitor consists of a headset that directs an array of ultrasound beams through the head and uses a proprietary algorithm to automatically detect the mid-cerebral artery, one of the major arteries supplying blood to the brain. The device then locks the relevant beam onto the artery and measures its blood flow. A machine attached to the headset gives an index of flow and peak velocity.
“The point is to give you a variable” that could be read similarly to a heart-rate monitor, says Michel Kliot, company cofounder and a neurosurgeon at University of Washington, where the technology was initially developed.
In November, the company received a military grant of $2.5 million to adapt the device for monitoring vasospasm in soldiers. Nearly half the soldiers who sustain blast injuries develop vasospasm, and the company plans to make a more rugged version of its commercial device for the battlefield.