Sound waves at frequencies above the human hearing threshold, Ultrasounds are commonly used in medical care. For example, in cases of injuries, ultrasound generates heat in deep tissues, which increases blood flow, reduces inflammation and muscle spasms, and speeds healing.
They also help doctors diagnose and monitor diseases, as well as provide first insight during pregnancy. But now, a team of scientists has come up with a new perspective: patients with conditions ranging from cancer to neurodegenerative diseases such as Alzheimer’s could soon benefit from recent advances in this technology.
Ultrasound is generated with a probe containing a material that converts electrical current into vibrations, and vice versa. As ultrasonic waves pass through the body, they are reflected at the boundaries of different types of tissue. The probe detects these reflections and converts them back into electrical signals that computers can use to create images of those tissues. Like echo-sonar.
In a recent essay, Richard J. Price of the University of Virginia notes that “more than 80 years ago, scientists discovered that focusing these ultrasonic waves on a volume the size of a grain of rice can heat and destroy brain tissue. This effect is analogous to concentrating sunlight with a magnifying glass to light a dry leaf. “I think some of the most promising applications of focused ultrasound include improving drug delivery to the brain, stimulating the immune response against cancer, and treating rare diseases of the central nervous system.”
one of the greatest problems that experts face when administering drugs is the blood-brain barrierevolution’s ideal solution to keep harmful substances away from the brain. This barrier only allows certain types of molecules to enter the brain, protecting against pathogens and toxins.
More than 20 years ago, pioneering studies determined that sending pulses of Low-intensity focused ultrasound could temporarily open the blood-brain barrier by causing the oscillation of microbubbles in blood vessels.
This oscillation pushes and pulls on the surrounding vascular walls, briefly opening small pores They allow drugs from the bloodstream to enter the brain. It is essential that the blood-brain barrier opens only where the focused ultrasound is applied.
“After many years of testing the safety of this technique and improving the control of ultrasonic energy – adds Price – we have developed several devices that use focused ultrasound to open the blood-brain barrier for therapeutic purposes.”
In fact, clinical trials are being carried out that evaluate the ability of these devices to deliver drugs to the brain and treat conditions such as glioblastoma, brain metastases, and Alzheimer’s disease.
Animal studies have shown that the use of focused ultrasound to open the blood-brain barrier may facilitate the delivery of gene therapies to their targets in the brain, opening the door to testing this technique in people.
“We have discovered that focused ultrasound can destroy solid tumors so that the immune system can better recognize and destroy cancer cells,” concludes Price.