Tinnitus 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). The mechanisms of subjective tinnitus are often obscure. While it is not surprising that direct trauma
Tinnitus masker for hearing loss. Sound generators (masking devices) have received Class II approval from the FDA. However, they are considered to be “experimental, investigational, or unproven” therapies. There is one report of a bone conduction vibration masker that transmits a 60 Hz fundamental with adjustable harmonics up to 1000 Hz. A commercial device based on the phenomenon (Aurex3) was approved by the FDA. A new development in tinnitus management is the use of high audio (10 kHz-20 kHz) or ultrasonic (20-100 kHz) via bone conduction. A 2012 Cochrane Review stated the available studies do not show strong evidence of the efficacy