Yes, they have a seperate sushi menu and when we were there I didn't find it limited at all, you don't have to sit at the sushi bar to be able to have a larger selection DH and I sat a a regular table and ordered a number of different sushi and rolls.
If you do go try the green tea creme brule, it's to die for. mmmm.
The food there is excellent and despite what the PP has said I didn't find their prices expensive at all.