The brain controls the entire body. Every function, every thought, memory, and movement starts in the brain. It’s important to keep it protected and healthy.
The blood-brain barrier (BBB) is a crucial part of keeping toxic substances, germs, and pathogens from reaching the brain. It’s often referred to in research as the "Holy Grail" regarding understanding how it works. The mechanism isn’t fully understood, but while it does an excellent job of keeping some things out, some essential substances, like drugs that treat brain cancer, cannot get to tumors and diseased tissue. It’s a fortress that’s almost too strong.
Researchers at Sunnybrook Health Sciences Centre in Toronto have just published promising research that demonstrated how focused ultrasound waves could be aimed at the brain to “jiggle” the BBB open. The study is a first of its kind because the participants were patients with Alzheimer’s disease. While it was a small group of only six patients, and the study was not therapeutic, but was set up just to see if the technology was safe and effective, it’s a significant beginning to finding ways to get medications and treatments exactly where they are needed.
The BBB isn’t like a door or a gate in one spot. It actually refers to the cells that line the blood vessels in the brain. They form interlocking patterns, like puzzle pieces or a zipper and only very tiny molecules can get through the microscopic openings in the cellular network. Dr. Nir Lipsman is the lead author of the study and serves as the Director of the Harquail Centre for Neuromodulation at Sunnybrook. Dr. Lipsman explained, “This is a critical first step. By successfully, safely and reversibly opening the blood-brain barrier in patients with early to moderate Alzheimer’s disease, we can support the continued investigation of focused ultrasound as a potential novel treatment, and further study the delivery of therapies that otherwise cannot access the brain.”
The tech works by first injecting tiny bubbles into the bloodstream. Using an MRI scanner, focused ultrasound waves are directed at a specific area of the brain. The bubbles vibrate, and the energy waves are powerful enough to create openings in the cells lining the blood vessels. Patients wore a helmet-like device in the scanner to help focus the sound waves. Radioactive dye showed up on the scanner images as proof that the barrier had opened as a result of the pulses of ultrasound energy. The researchers verified with a follow-up scan the next day that showed the opening was temporary. There were no adverse effects reported in the group of patients.
It’s not the first time Sunnybook scientists have breached the barrier. In 2015 they used a similar ultrasound process to open the barrier and deliver drugs directly to a tumor. ( The technology has applications for brain cancer, Parkinson’s, ALS and other neurological conditions. More studies are planned to see how it works when drug therapies are added to the protocol. For now, the fact that it works and is safe is a slice of hope for patients and their families. Check out the video below to hear Dr. Lipsman talk about what this could mean for neuroscience.