Tinnitus is the perception of sound when no external sound is present. This phantom noise can manifest as ringing, buzzing, roaring, clicking, or hissing. While common, its occurrence in only one ear, known as unilateral tinnitus, often warrants more focused attention than bilateral tinnitus, as it can indicate specific underlying causes.
The Significance of Tinnitus in One Ear
Unilateral tinnitus is more significant than tinnitus affecting both ears. While general tinnitus can be benign, one-sided tinnitus may indicate an underlying medical condition. This is because the auditory system has distinct pathways for each ear leading to the brain. A localized issue affecting one ear, its auditory nerve, or a specific part of the brain can cause sound perception limited to that side.
The auditory nerve, also known as the vestibulocochlear nerve, transmits sound and balance information from the inner ear to the brain. Problems along this pathway can lead to symptoms confined to one ear. Therefore, unilateral tinnitus often prompts healthcare professionals to investigate specific conditions affecting the auditory system on that side.
Everyday Factors Leading to Unilateral Tinnitus
Several common factors can lead to tinnitus affecting only one ear. One frequent cause is earwax impaction, where earwax buildup in one ear canal blocks sound and creates pressure, causing ringing or buzzing. Removing the excess earwax often resolves this type of tinnitus.
Temporary noise exposure can also induce one-sided tinnitus. Loud sounds, such as from a concert or power tools, can temporarily damage the delicate hair cells in the inner ear of the exposed side, leading to a ringing sensation. This typically resolves as the ear recovers, but repeated exposure can lead to permanent damage.
Eustachian tube dysfunction, involving issues with the tube connecting the middle ear to the back of the nose, can cause pressure changes and a feeling of fullness in one ear, sometimes accompanied by tinnitus. Problems with the temporomandibular joint (TMJ) on one side can refer pain and sound to the adjacent ear. Localized trauma to the head or neck can also impact nerves or blood flow related to hearing, potentially resulting in unilateral tinnitus.
Medical Conditions Causing One-Sided Tinnitus
Medical conditions can also manifest as unilateral tinnitus. Meniere’s disease, an inner ear disorder, commonly affects one ear and is characterized by fluctuating tinnitus, hearing loss, vertigo (a spinning sensation), and a feeling of fullness in the affected ear, thought to result from an imbalance of fluid.
An acoustic neuroma is a non-cancerous growth that develops on the vestibulocochlear nerve. As this tumor slowly grows, it can press on the auditory and balance nerves, causing unilateral tinnitus, hearing loss, and balance issues. Though benign, its growth can interfere with brain function, making early detection important.
Otosclerosis involves abnormal bone growth in the middle ear, which can impede sound vibrations and lead to hearing loss and tinnitus. This condition causes the tiny bones in the middle ear to stiffen, preventing them from vibrating correctly.
Additionally, certain vascular issues can cause pulsatile tinnitus, a rhythmic whooshing or throbbing sound that beats with one’s heartbeat. This can be due to changes in blood flow in vessels near the ear and warrants investigation for circulatory problems. Lastly, some medications are known to be ototoxic, meaning they can cause damage to the ear. In some instances, these side effects might affect one ear more significantly, causing unilateral tinnitus.
When to Consult a Healthcare Professional
Any new, persistent, or worsening tinnitus experienced in only one ear warrants a medical evaluation. While some causes are benign, unilateral tinnitus can sometimes signal a more serious underlying condition. It is advisable to seek medical advice for any one-sided tinnitus that does not resolve quickly or is accompanied by other symptoms.
Specific “red flags” include sudden hearing loss in the affected ear, episodes of vertigo or dizziness, or facial weakness. Tinnitus accompanied by severe pain or other neurological symptoms also requires prompt attention. During an initial evaluation, a healthcare professional will typically take a detailed medical history, perform an examination of the ear, and may recommend hearing tests.