How to get volume data into a Geomery Nodes network?

I’m using a mesh which is being converted into a volume to produce volumetric data. This data is then modified by a shader to further distort it. Now I want to convert that volume data back into a mesh.

(Related to this thread: Is there a way to add a 3D noise texture to a volume? - #5 by Mark_McKay)

I can’t find a way to convert the final volume into a mesh. The geometry nodes just have a Geometry input which seems to ignore the volume data. Is there a way to do this?