Getting drugs to treat maladies in the brain is hampered by the blood-brain barrier, a protective shield that makes sure only the right chemicals pass through. Ultrasound has become a promising way of opening up pathways in the blood-brain barrier to let drugs in, but it has come with accompanying side effects. These include letting unwanted chemicals into the brain during treatment and accidental damage to tissues within the target area.
Scientists at Imperial College London have been looking into optimizing ultrasound to be able to deliver drugs while minimizing the side effects, and turns out that the wavelength of the delivered ultrasound is key.
Typically, the way the technology usually works is that microbubbles are injected into the blood stream and made to resonate using ultrasound, essentially jiggling their way across the blood-brain barrier. The wavelengths that have been usually used have been relatively long, which are optimized to get the microbubbles to jiggle the most. The Imperial team tried to see whether shorter wavelengths would work and found out that indeed, coupled with more rapid pulses, they seem to work even better than longer wavelengths. Moreover, the side effects will hopefully be shown in the future to be reduced.
So far the research was conducted on lab mice to identify whether the technique would work at all, so further studies will be needed to identify potential side effects and compare this approach to the more “traditional” longer wavelengths.
Flashbacks: Focused Ultrasound and Microbubbles Push Drugs Across Blood-Brain Barrier…; Focused Ultrasound and Intranasal Drug Delivery for Brain Cancer Therapy…; First Alzheimer’s Patient Treated with Focused Ultrasound to Open Blood-Brain Barrier…