1. Blood brain barrier and CSF should be separate for all but tiny molecules. It's why CT angiograms are able to visualize distinct vessels. So it is pretty hard to directly interact with this sort of thing in vivo
2. A good chunk of the neuro community have been operating under the assumption that some of those mouse model findings are mechanisms in humans too. Since we couldn't easily prove it, people used a bunch of next best tools with fancy imaging that demonstrated it was very likely. On top of furter proof, this sort of study allows us to begin pinpointing exactly how close our next best tools are at estimating in vivo processes without opening up the head.
1. Blood brain barrier and CSF should be separate for all but tiny molecules. It's why CT angiograms are able to visualize distinct vessels. So it is pretty hard to directly interact with this sort of thing in vivo
2. A good chunk of the neuro community have been operating under the assumption that some of those mouse model findings are mechanisms in humans too. Since we couldn't easily prove it, people used a bunch of next best tools with fancy imaging that demonstrated it was very likely. On top of furter proof, this sort of study allows us to begin pinpointing exactly how close our next best tools are at estimating in vivo processes without opening up the head.