The brain is our busiest organ, and like any complex production site, it generates plenty of waste. Normally, that’s not a problem: metabolic byproducts such as proteins, gases, and cellular debris are cleared through an intricate waste-disposal network. But when this drainage system falters and waste accumulates, the risk of neurological diseases like Alzheimer’s rises significantly.

To better understand how exactly the brain disposes of toxic waste, and potentially uncover ways to prevent neurodegenerative disease, researchers at the Gladstone Institute of Neurological Disease in San Francisco developed a new tracer that reveals the brain’s waste-removal system in unprecedented detail without disrupting the delicate process itself, as earlier contrast fluids often did.