Programmatically detect dereferenciation in function

[Luca3317]

Given a function (HighFunction) and one of its local variables, how can I, using the API, figure out if that variable is dereferenced in that function?

Because I couldnt find anything regarding that, what I did was iterate over the Pcode instructions, check if its a LOAD or STORE instruction and then checked if a storage varnode of said variable serves as relevant input. This worked fine until I tried some functions with double dereferenciation (i.e. var[i][j]).

Is there some functionality to the API that I missed?