[BenFranklin100]

It doesn’t. The brain must be cleared which generally involves removing lipids so the tissue has a homogeneous index of refraction throughout. Given lipids are an extremely important component of the brain (for instance myelin is a lipid rich material that surrounds axons) even if one were able to clear the brain without excising it from the skull, the clearing process essentially destroys the brain by preventing it from function properly.

[robwwilliams]

Correct. But that is where the lightsheet adds sufficient resolution. MRI for the “mesopic” scale, lightsheet for for microscopic scale to 0.2 microns, and selective elecron microscopy down as low as tissue quality will allow.

[BenFranklin100]

You’re not even responding to the original questions, which is is lightsheet microscopy capable of imaging entire living brains? Pay attention.

[kevviiinn]

Can you use light microscopy on a living brain? No

[BenFranklin100]

Two and three photon microscopy works on living brains down to depth of approximately 1.5 mm. A company even sells head mounted miniature microscopes for mice. Try to refrain from commenting on topics outside your expertise.