'Tis the season of champagne quaffing, and while it’s a well-known fact that bubbles of the alcoholic variety go rapidly to a person’s head (I write from experience), it’s a lesser-known fact that bubbles of the medical variety (pictured) are also excellent at getting to the brain – specifically at delivering brain-targeted medications. The brain is difficult to access, medically speaking, because the blood-brain barrier – a specialsed lining of the brain’s blood vessels that prevents bacteria and viruses from entering – also blocks most drugs. Scientists are investigating ways to bypass the barrier, and one recent method under review is microbubbles with focused ultrasound. After drug-loaded microbubbles are injected into the blood, sound waves are directed at blood vessels in the brain making the bubbles jiggle erratically – like merry employees at an office Christmas disco. The jiggling bubbles then temporarily break down the barrier and release their contents into the brain.
Image from work by C. Sierra et al., Ultrasound Elasticity Imaging Laboratory Columbia University
Department of Biomedical Engineering, Ultrasound and Elasticity Imaging Laboratory, Columbia University, New York, NY, USA
Image copyright held by original authors
Research published in the Journal of Cerebral Blood Flow & Metabolism, June 2016