Board Thread:Theories and Speculation/@comment-1512913-20161119171442/@comment-1512913-20161204183022

There is no requirement. Only the power/potential of the 'special brain chakra' (Sharingan/Mangekyou Sharingan) has to be reached, the eyes are just representation of the special brain chakra, so they are not needed for the Susanoo, the power is in the brain.