Here in the S-wing of Toronto’s Sunnybrook Hospital, Mainprize and his research team accomplished on Thursday what no one in the world has ever done before: Using focused ultrasound waves, they have opened the human blood-brain barrier, paving the way for future treatment of an array of currently impossible or hard-to cure-illnesses – from brain cancer to certain forms of depression, stroke, Parkinson’s disease and Alzheimer’s disease.
I’m not very keen on intentionally tearing even small holes in capillaries. It may work well for tumors, since the goal is to damage that tissue anyway. But using this to deliver drugs to healthy tissue sounds problematic. The Blood-Brain Barrier exists for some very good reasons. If used in healthy tissue this would essentially imitate a small hemorrhagic stroke for 8-12 hours. That’s a lot of time for glutamate toxicity alone, and there are many other substances in systemic circulation that aren’t tolerated well in the brain.