The physician may also request an OAE test (which is very sensitive to noise induced hearing damage), an ECochG (looking for Meniere's disease and hydrops, an MRI/MRA test (scan of the brain), a VEMP (looking for damage to other parts of the ear) and several blood tests (ANA, B12, FTA, ESR, SMA-24, HBA-IC, fasting glucose, TSH, anti-microsomal antibodies).
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.