What does a focused ultrasound procedure look like?

The procedure involves patients coming into the hospital. A frame is attached directly to their head with two pins in the front and two pins in the back. Then their head is placed inside a helmet. The lining of the helmet contains over 1,000 individual ultrasound transducer elements, or 1,000 sources of ultrasound. With their head in the helmet, they go into an MRI scanner. Then, we use high-resolution imaging to look at their brain and select which region of the brain to open the blood-brain barrier. But it’s not enough to just apply ultrasound. We need to inject patients with a special contrast agent that contains microbubbles. These microbubbles are small and contain gas. They circulate throughout the body, then get to the brain. When these microbubbles are exposed to ultrasound, they vibrate, increasing and decreasing rapidly in size. That vibration pulls apart the cells making up the blood-brain barrier, and it does so temporarily for about six hours. So there’s a six-hour window of opportunity to deliver whatever’s in the bloodstream into the brain.