I want o extrude my geometry

I have point clouds and *.stl file from mimcs software for cerebral artery. I want to create structure around the poind clouds and extrude my structure for getting artery wall thickness for FSI analysis.this is the pic of my point clouds

help me plz

Looks like a dense mesh. Maybe try MeshOutline and then extrude the resulting curve… --Mitch

Edit: Oh, and is that a paid-for version of Rhino you have there, I’ve never seen versions labeled “Full”, just “Commercial” and “Educational”…?