cell type and if condition

I have a cell 1x200 B and I want to use it in an if condition. Here an exemple with an 1x4 cell

1x4 cell
8   []  []  []

that I search is to say : if all cell exept the first are empty (other saying 1x0 double) so I return at the begin of the initial loop else I applied other things. I start with this but it doesn't work :

if B{1,2:end}==[]
           return
else
bla bla bla
end