Unilateral hearing loss (UHL) affects an individual’s ability to hear sounds in only one ear, while the other ear maintains typical function. UHL can range from mild to profound. While some causes are minor and temporary, others may indicate a significant underlying health issue requiring prompt medical attention. Understanding potential reasons for UHL helps determine appropriate evaluation and care.
Common and Minor Causes
A frequent cause of reduced hearing in one ear is earwax accumulation. Earwax can build up and block the ear canal, leading to a feeling of fullness or muffled hearing.
Middle ear fluid, often developing after a cold, allergies, or a sinus infection, is another common reason. Fluid collects behind the eardrum, dampening sound transmission and causing pressure and muffled hearing.
A foreign object lodged in the ear canal can also impede hearing. These blockages can cause discomfort and reduce hearing ability.
Swimmer’s ear, or otitis externa, is an outer ear canal infection causing swelling and inflammation. This leads to pain, itching, and muffled hearing. Untreated swimmer’s ear can sometimes lead to complications.
More Serious or Urgent Causes
Sudden sensorineural hearing loss (SSNHL) is a rapid loss of hearing, usually in one ear, occurring over hours or days. This condition affects the inner ear or the auditory nerve. It may be accompanied by ringing in the ear (tinnitus), dizziness, or a feeling of ear fullness. Prompt medical evaluation is advised, as early intervention can improve recovery chances.
An acute middle ear infection can lead to significant hearing loss, with pain, fever, or fluid discharge. These infections, caused by bacteria or viruses, inflame the middle ear, impairing the eardrum’s ability to vibrate properly. If left untreated, severe infections can potentially damage the eardrum or spread.
A perforated eardrum, a hole or tear in the tympanic membrane, can also cause hearing loss. This can result from trauma, such as a direct injury or a loud noise, or from severe ear infections. The hole prevents the eardrum from vibrating efficiently, which reduces sound conduction.
Meniere’s disease is an inner ear disorder causing fluctuating hearing loss, severe dizziness (vertigo), ringing, and fullness in the affected ear. This condition is believed to be associated with an imbalance of fluid in the inner ear.
Acoustic neuroma, though rare, is a non-cancerous tumor that develops on the nerve leading from the inner ear to the brain. This growth can cause gradual hearing loss, tinnitus, balance issues, and sometimes facial numbness. Barotrauma, or ear damage from pressure changes, can also result in hearing loss. This occurs when there’s a significant difference in pressure between the middle ear and the external environment, commonly experienced during activities like flying or scuba diving.
When to Seek Medical Care
Any sudden hearing loss, especially in one ear, warrants immediate medical attention. This is particularly true if it occurs rapidly, over hours or days, as it could indicate a serious medical condition like sudden sensorineural hearing loss, which benefits from timely treatment.
Medical consultation is advisable if the hearing loss is accompanied by additional symptoms. These include such as severe ear pain, fever, ear discharge, dizziness, or vertigo. Professional help is also important if hearing loss follows a head injury or trauma.
Consult a healthcare provider if hearing loss does not improve within a day or two, especially if simple self-care measures have not helped. Any personal concern about changes in hearing should also prompt a visit to a doctor or audiologist.
Medical Assessment and Management
Medical assessment for unilateral hearing loss begins with a consultation. A healthcare provider will inquire about your medical history and conduct a physical ear examination, often using an otoscope to look inside. This helps identify visible issues like earwax blockages or infection signs.
Diagnostic tests may be necessary to determine the cause and extent of hearing loss. An audiologist often performs a comprehensive hearing evaluation (audiometry) to measure your hearing abilities across different frequencies and sound levels. If serious causes are suspected, imaging studies like an MRI or CT scan might be recommended.
Treatment varies depending on the cause. Professional earwax removal can restore hearing. Ear infections may be managed with antibiotics or other medications. For sudden sensorineural hearing loss, corticosteroids, administered orally or directly into the ear, are often considered.
Smaller perforated eardrums may heal on their own, but larger ones might require surgical repair, such as tympanoplasty. If fluid persists behind the eardrum, a procedure like myringotomy to drain the fluid may be considered. Patients may also be referred to specialists, such as an ENT (ear, nose, and throat) doctor for medical or surgical management, or an audiologist for hearing assessments and potential hearing devices.