Tinnitus is not a disease — it’s a symptom. It’s a sign that something is wrong with your auditory system, which includes your ear, the auditory nerve that connects the inner ear to the brain, and the parts of the brain that process sound. There are a variety of different conditions that can cause tinnitus. One of the most common is noise-induced hearing loss.
The important thing to remember about tinnitus is that the brain’s response to these random electrical signals determines whether or not a person is annoyed by their tinnitus or not. Magnetoencephalography (MEG, for short) studies have been used to study tinnitus and the brain. MEG takes advantage of the fact that every time neurons send each other signals, their electric current creates a tiny magnetic field. MEG allows scientists to detect such changing patterns of activity in the brain 100 times per second. These studies indicated tinnitus affects the entire brain and helps with understanding why certain therapies are more effective than others.
It is possible that the most common cause of pulsatile tinnitus is sigmoid sinus diverticulum and dehiscence, which can be collectively referred to as sinus wall abnormalities or SSWA. The sigmoid sinus is a blood carrying channel on the side of the brain that receives blood from veins within the brain. The blood eventually exits through the internal jugular vein. Sigmoid sinus diverticulum refers to the formation of small sac-like pouches (diverticula) that protrude through the wall of the sigmoid sinus into the mastoid bone behind the ear. Dehiscence refers to absence of part of the bone that surrounds the sigmoid sinus in the mastoid. It is unknown whether these conditions represent different parts of one disease process or spectrum, or whether they are two distinct conditions. These abnormalities cause pressure, blood flow, and noise changes within the sigmoid sinus, which ultimately results in pulsatile tinnitus. Narrowing of the blood vessel that leads into the sigmoid sinus, known as the transverse sinus, has also been associated with pulsatile tinnitus.
Tinnitus is not a disease but a symptom that can result from a number of underlying causes. One of the most common causes is noise-induced hearing loss. Other causes include ear infections, disease of the heart or blood vessels, Ménière's disease, brain tumors, emotional stress, exposure to certain medications, a previous head injury, and earwax. It is more common in those with depression.
Even with all of these associated conditions and causes, some people develop tinnitus for no obvious reason. Most of the time, tinnitus isn’t a sign of a serious health problem, although if it’s loud or doesn’t go away, it can cause fatigue, depression, anxiety, and problems with memory and concentration. For some, tinnitus can be a source of real mental and emotional anguish.
Acoustic neuroma: This is a rare subjective cause of tinnitus, and includes a certain type of brain tumor known as an acoustic neuroma. The tumors grow on the nerve that supplies hearing and can cause tinnitus. This type of the condition usually are only noticed in one ear, unlike the more common sort caused by hearing loss usually seen in both ears. Causes of objective tinnitus are usually easier to find.
The outlook for tinnitus depends on its cause. In people with tinnitus related to earwax buildup or medications, the condition usually will go away when the earwax is removed or the medication is stopped. In people with tinnitus related to sudden, loud noise, tinnitus may improve gradually, although there may be some permanent noise-related hearing loss.
In persons with pulsatile tinnitus, additional tests maybe 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 pulsation is arterial, these tests have no effect.
Auditory-somatosensory stimulation is a similar treatment approach to Kilgard’s, in that its goal is to retune the faulty patterns of brain activity that can cause tinnitus. It involves pairing sounds played in the ear with specially timed electric impulses, which are administered to touch-sensitive nerves using a pad attached to the neck, Dr. Shore explains about the research she’s working on.
Steven Doerr, MD, is a U.S. board-certified Emergency Medicine Physician. Dr. Doerr received his undergraduate degree in Spanish from the University of Colorado at Boulder. He graduated with his Medical Degree from the University Of Colorado Health Sciences Center in Denver, Colorado in 1998 and completed his residency training in Emergency Medicine from Denver Health Medical Center in Denver, Colorado in 2002, where he also served as Chief Resident.
In Canada, the level of funding or engagement towards tackling the problem of tinnitus is comparably minimal. But with recent headlines about the effects of tinnitus on those in police forces2 and frustration among veterans, this may change. Because of the progress made in tinnitus treatment and management research – including work done right here in Canada – the time is right to offer tinnitus sufferers effective options and the support they need. While many with tinnitus are not yet aware that there are ways to reduce or manage the constant ringing, hissing or buzzing in their ears, as more health care professionals make effective options available, word will spread. In time, tinnitus and its impact on quality of life can be reduced.
Tinnitus (pronounced ti-ni-tis), or ringing in the ears, is the sensation of hearing ringing, buzzing, hissing, chirping, whistling, or other sounds. The noise can be intermittent or continuous, and can vary in loudness. It is often worse when background noise is low, so you may be most aware of it at night when you're trying to fall asleep in a quiet room. In rare cases, the sound beats in sync with your heart (pulsatile tinnitus).