Hi, again, Nonna,
I've heard that it may take quite awhile for middle ear fluid to drain, and I hope that will resolve your pulsating. However, if it doesn't, my suggestion would then be to seek out another doctor who is a specialist, such as a neurotologist or neurologist. They know a great deal more about pulsatile tinnitus, and may then suggest some tests to determine a possible cause.
Good luck, and please keep me posted on how you're progressing with the fluid drainage.
Best wishes,
Karen