Tinnitus, or ringing in the ears, affects a significant amount of the population at one time or another in their lives. While it is normal for someone to experience intermittent episodes of buzzing, ringing, or tonal sounds in the ear from time to time, some people experience a condition which is much more persistent and sometimes more bothersome. Prevalence is estimated between 5-42% of the population.
The condition itself does not have one root cause or pathology associated with it. It can be caused by noise trauma, physical trauma, disease, aging, and as a side-effect of some medications. A number of different structures and conditions can contribute to the presentation and the symptoms that an individual experiences. This can include cardiovascular, neurological, mechanical, and inflammatory disease states. These factors will produce a sensitivity in the nervous system, leading to changes in the brain that can produce the phantom sound or make it increasingly difficult to shift our attention elsewhere.
From a cardiovascular perspective, an increase in blood pressure can sometimes result in the ability to hear a thudding or pounding, drum-beat like sound. This can occur unilaterally or bilaterally. This can also be the result of inappropriate formation of small blood vessels in the inner ear and surrounding tissues which does not allow blood to flow through them smoothly in all situations. Anything that is of a vascular nature will require assessment and investigations as recommended by the appropriate physician and/or specialist and is outside the scope of physical therapy.
From an inflammatory basis, a number of structures in the face, head, and ear can contribute to the perception of sound if they become irritated or sensitive. This include various nerves, the sinuses, eustachian tubes, and even the middle ear bones that conduct sound to the eardrum. The eardrum itself can be a source of irritation if it becomes inflamed or scarred as well. The treatment for this typically is medical in nature to try and reduce swelling/inflammation in the specific tissues.
The neurological mechanism is the most common pathway that relates to idiopathic tinnitus. Idiopathic referring to an onset of symptoms with no known injury or mechanism. This can be due to sensitization of the peripheral nervous system, central nervous system, or a combination of the two. This is typically treated through a combination of medication, education, and stress-reduction strategies.
Mechanically, the upper cervical spine and jaw joints can contribute to a presentation of tinnitus in some cases through their connection into a cluster of nerves referred to as the trigeminocervical complex. Since the trigeminal nerve has connections to the other cranial nerves, overwhelming stimulus of these pathways can contribute to the intensity and frequency of symptom presentation. On the bright side, appropriate mechanical treatment and education surrounding these tissues can sometimes provide improvement in the tinnitus symptoms that are experienced. Not everyone has a mechanical presentation, but since treatment and therapy are non-invasive, it can be worthwhile to consider assessment by a trained healthcare practitioner.
Another useful avenue of assessment for those suffering from tinnitus is a comprehensive hearing assessment through an Audiologist. This will assist with understanding the unique features of a patient’s presentation and help other practitioners determine an appropriate course of action. Audiologists also have the ability to treat some aspects of tinnitus with assistive devices that can create white noise, amplify normal hearing, and try to retrain the brain/nervous system to ignore the tinnitus itself.
One of the most important things to note regarding tinnitus is that the amount of distress or the perceived volume of the sound does not relate to the severity of the condition. Louder tinnitus does not mean that someone is at greater risk of harm or injury/disease.
~ Trent, PT
References:
Somatosensory tinnitus: Current evidence and future perspectives. Ralli, M. et al. Journal of International Medical Research. 2017.
Maladaptive plasticity in tinnitus - triggers, mechanisms and treatment. Shore, S., Roberts, L., Langguth B. Nat Rev Neurol. 2016.
Current insights in noise-induced hearing loss: a literature review of the underlying mechanism, pathophysiology, asymmetry, and management options. Le, T., Straatman, L., Lea, J., Westerberg, B. Journal of Otolaryngology - Head & Neck Surgery. 2017.