Bit of overlapping here and some definitions need applying.
2 main sensations in the ear, due to completely different causes.
1) Tinnitus
2) Pulsations
Tinnitus is a high pitched ringing noise as described by trt
Pulsations, heartbeat as described by carlton.
Carlton...ventilating tube is a small tube inserted into the ear drum under an operating microscope. Easy, day case and no big deal and might well relieve the symptoms of a Patulous Eustachian tube, if the diagnosis was PET.
In my opinion it is the diagnosis of despair in many cases, and used when no diagnosis comes to mind.