How can I delete Images correctly which were uploaded with Filefield/Imagefield? --> delete also in ImageCache-Folders

Hey,
I hope you can help me.
I want to develope a module which deletes my own images. The images were uploaded with cck+imagefield.
But if I delete an image, the original should be deleted AND the image in ALL Presetfolders of ImageCache.

How can I do that?

Thank you!!!

Greets, David