ABR (ABR) testing may show some subtle abnormalities in otherwise normal persons with tinnitus (Kehrle et al, 2008). The main use of ABR (ABR test) is to assist in diagnosing tinnitus due to a tumor of the 8th nerve or tinnitus due to a central process. A brain MRI is used for the same general purpose and covers far more territory, but is roughly 3 times more expensive. ABRs are generally not different between patients with tinnitus with or without hyperacusis (Shim et al, 2017).
Pulsatile tinnitus: This problem usually is related to blood flow, either through normal or abnormal blood vessels near the ear. Causes of pulsatile tinnitus include pregnancy, anemia (lack of blood cells), overactive thyroid, or tumors involving blood vessels near the ear. Pulsatile tinnitus also can be caused by a condition known as benign intracranial hypertension (an increase in the pressure of the fluid surrounding the brain).
It can often be very helpful to talk to someone who understands how you are feeling, who can reassure you about any anxieties you may have, and answer your questions. We can provide details of self-help groups and contacts in the UK, and we also run a helpline on 0800 018 0527. Most of the people who run groups or are contacts have tinnitus themselves and have been helping people with the condition for a long time. Even if you don't want to take part in group activities, it can be a comfort to know there is someone you can contact.
Another way of splitting up tinnitus is into objective and subjective. Objective tinnitus can be heard by the examiner. Subjective cannot. Practically, as there is only a tiny proportion of the population with objective tinnitus, this method of categorizing tinnitus is rarely of any help. It seems to us that it should be possible to separate out tinnitus into inner ear vs everything else using some of the large array of audiologic testing available today. For example, it would seem to us that tinnitus should intrinsically "mask" sounds of the same pitch, and that this could be quantified using procedures that are "tuned" to the tinnitus.
A common cause of tinnitus is inner ear hair cell damage. Tiny, delicate hairs in your inner ear move in relation to the pressure of sound waves. This triggers cells to release an electrical signal through a nerve from your ear (auditory nerve) to your brain. Your brain interprets these signals as sound. If the hairs inside your inner ear are bent or broken, they can "leak" random electrical impulses to your brain, causing tinnitus.