Sensory hearing loss, also known as sensorineural hearing loss (SNHL), is a type of hearing loss caused by damage to the inner ear (cochlea), the auditory nerve, or the brain's central auditory pathways. It's the most common type of hearing loss.
Understanding Sensorineural Hearing Loss (SNHL)
SNHL occurs when there's a problem with how sound vibrations are converted into electrical signals in the inner ear, or how those signals are transmitted to the brain. This can result in a reduction in sound sensitivity, affecting the ability to hear quiet sounds, understand speech clearly, or both.
Causes of Sensorineural Hearing Loss
Several factors can contribute to SNHL, including:
- Age-related hearing loss (Presbycusis): This is a gradual decline in hearing due to natural aging processes.
- Noise-induced hearing loss (NIHL): Prolonged exposure to loud noise can damage the hair cells in the cochlea.
- Genetic factors: Some individuals are predisposed to hearing loss due to inherited genes.
- Infections: Viral or bacterial infections (e.g., measles, mumps, meningitis) can damage the inner ear.
- Ototoxic medications: Certain medications (e.g., some antibiotics, chemotherapy drugs) can be toxic to the inner ear.
- Head trauma: Injury to the head can damage the inner ear or auditory nerve.
- Tumors: In rare cases, tumors on the auditory nerve can cause hearing loss.
- Meniere's disease: This inner ear disorder can cause vertigo, tinnitus, and hearing loss.
Symptoms of Sensorineural Hearing Loss
Common symptoms of SNHL include:
- Difficulty hearing quiet sounds
- Trouble understanding speech, especially in noisy environments
- Tinnitus (ringing, buzzing, or hissing in the ears)
- Feeling that others are mumbling
- Dizziness or balance problems (in some cases)
Diagnosis and Treatment
Diagnosis typically involves a hearing test (audiogram) to determine the type and severity of hearing loss. Treatment options may include:
- Hearing aids: These amplify sound to improve hearing.
- Cochlear implants: These surgically implanted devices bypass the damaged portions of the inner ear and directly stimulate the auditory nerve.
- Assistive listening devices (ALDs): These can help in specific situations, such as watching television or talking on the phone.
- Communication strategies: Learning techniques to improve communication, such as lip reading and using visual cues.
