An ultrasound is another test that may be used to aid in the diagnosis of tinnitus. An ultrasound uses reflected high-frequency sound waves and their echoes to create images of structures within the body. An ultrasound can reveal how blood flows within vessels, but is only useful for accessible vessels. It is not helpful for blood vessels within the skull.
What does he mean by “ends up in the brain”? Essentially, something that causes even temporary hearing damage — such as exposure to very loud noise or a blow to the head — can change activity patterns in the brain in ways that cause the ringing. Even though some damage or problem in the ear triggered tinnitus to begin with, you continue to hear the sound you do because of a signal from the brain.
Patients with head or neck injury may have particularly loud and disturbing tinnitus (Folmer and Griest, 2003). Tinnitus due to neck injury is the most common type of "somatic tinnitus". Somatic tinnitus means that the tinnitus is coming from something other than the inner ear. Tinnitus from a clear cut inner ear disorder frequently changes loudness or pitch when one simply touches the area around the ear. This is thought to be due to somatic modulation of tinnitus. We have encountered patients who have excellent responses to cervical epidural steroids, and in persons who have both severe tinnitus and significant cervical nerve root compression, we think this is worth trying as treatment.
Some people experience a sound that beats in time with their pulse, known as pulsatile tinnitus or vascular tinnitus. Pulsatile tinnitus is usually objective in nature, resulting from altered blood flow, increased blood turbulence near the ear, such as from atherosclerosis or venous hum, but it can also arise as a subjective phenomenon from an increased awareness of blood flow in the ear. Rarely, pulsatile tinnitus may be a symptom of potentially life-threatening conditions such as carotid artery aneurysm or carotid artery dissection. Pulsatile tinnitus may also indicate vasculitis, or more specifically, giant cell arteritis. Pulsatile tinnitus may also be an indication of idiopathic intracranial hypertension. Pulsatile tinnitus can be a symptom of intracranial vascular abnormalities and should be evaluated for irregular noises of blood flow (bruits).
Atherosclerosis. With age and buildup of cholesterol and other deposits, major blood vessels close to your middle and inner ear lose some of their elasticity — the ability to flex or expand slightly with each heartbeat. That causes blood flow to become more forceful, making it easier for your ear to detect the beats. You can generally hear this type of tinnitus in both ears.