Screen Resolution and Tlistbox

[Razor]

I got a problem i can generate supported resolution modes in a ilstbox,right..
Then i got this after calling the enumdisplaysettings.This is in a listbox.

640X480 8 bit
640X480 8 bit
640X480 8 bit
640X480 8 bit
640X480 16 bit
640X480 16 bit
640X480 16 bit
640X480 16 bit

Can i somehow filter(remove) the items that have the same name.Couse i dont need that many items that are the same its confusing!