Unused files in iTunes folder

Hi everyone,

I am very sure that over time many unused / abandoned files have cumulated inside my iTunes Music folder (I am using "Copy files to iTunes Music folder" and "Keep my iTunes folder organized)... I guess it happened to everyone every now and then, that you delete a file within iTunes and then hit the wrong button (because it is assigned to the Return key) when asked if you want to move the corresponding file to trash.

So I checked the number of folders inside my iTunes Music folder and it has many more folders, than I have artists inside iTunes, which is proof, that there have to be abandoned files.

Please help me to find a way to identify these or let iTunes scan the whole folder, or anything, which might lead to a clean iTunes Music folder which is 100% in sync with what is listed within iTunes.

Thanks in advance, kind regards,
J.M.