In this form of tinnitus the sufferer hears something resembling their heartbeat in their ear. The cause for pulsatile tinnitus usually involves vascular, tumor or muscular causes. A blood vessel may be close to the eardrum, a vascular tumor such as a "glomus" may fill the middle ear, or a vein similar to a varicose vein may make enough noise to be heard. Other pulsatile tinnitus possibilities include dehiscence of the jugular bulb, and an abberently located carotid artery. An enlarged jugular bulb on the involved side is common in persons with venous type pulsatile tinintus.
In persons with pulsatile tinnitus, additional tests may be proposed to study the blood vessels and to check the pressure inside the head. Gentle pressure on the neck can be performed to block the jugular vein but not the carotid artery. The Valsalva maneuver reduces venous return by increasing intrathoracic pressure. If there is a venous hum, this usually abates or improves markedly. If the pulsatile tinnitus pulsation is arterial, these tests have no effects. MRI/MRA or CT is often suggested in younger patients with unilateral pulsatile tinnitus. In older patients, pulsatile tinnitus is often due to atherosclerotic disease and it is less important to get an MRI/MRA. In some cases of pulsatile tinnitus a lumbar puncture may be considered if there is a possibility of benign intracranial hypertension. More invasive pulsatile tinnitus testing includes the "balloon occlusion test", where a balloon is blown up in the internal jugular vein to see if it eliminates pulsatile tinnitus.
It is strongly recommended that all individuals with pulsatile tinnitus locate an excellent physician with interest in the circulatory system and complete a thorough examination. Based on research, which included reviewing 7 otolaryngology textbooks and over 250 research studies, data appears to support the underlying cause for detecting a pulsatile tinnitus as physiologic in nature. That said, there are many, many cases of pulsatile tinnitus that defy diagnosis and identification of the causative agent.