3d custom antenna elements

Is there a way to use 3d shapes imported from .stl, and other 3d model types as custom antenna elements ?

[Jorge Cossio]

I am also interested in finding out if this is possible. I've managed to import and mesh 2 helical antennas of different sizes, looking to obtain the S21 parameters of both. I've had success with other 2D shapes, but there is no real way for simulating our antennas using 2D architecture.