Sensorineural hearing loss can be divided into two parts: sensory and neural. Sensorineural hearing loss is brought on by inner ear or audio nerve dysfunction. The sensory component can stem from damage to the organ of Corti or the hair cells’ inability to stimulate the hearing nerves. The neural component stems from severe damage to the organ of Corti, which causes the hearing nerves to degenerate.
Annually, there are 4,000 cases of sensorineural hearing loss in the U.S., most commonly affecting those aged 30 to 60 years.
In many cases of sensorineural hearing loss, patients can recover, but in about 15 percent of cases it can actually become progressively worse, and hearing aids or cochlear implants may be required as treatment.
Causes of sensorineural hearing loss
Sensorineural hearing loss usually takes place when damage occurs in the inner ear, the cochlea, or the nerve pathways between the ear and the brain. There are over 100 different causes of sensorineural hearing loss, and yet in some cases, a cause may never be uncovered.
Possible causes for sensorineural hearing loss include:
- Malformation of the inner ear
- Head injury or trauma
- Prolonged exposure to loud noises
- Neurologic conditions like multiple sclerosis
- Autoimmune diseases
- Meniere’s disease
- Lyme disease
- Ototoxic medication
- Snake bite venom
- Blood circulation problems
- Abnormal tissue growth or tumors
- Blood vessel disease
Signs and symptoms of sensorineural hearing loss
Symptoms of sensorineural hearing loss may include a reduction in hearing upon awakening, or changes in hearing when using headphones or talking on the phone. Some may experience a sudden hearing loss followed by a loud pop.
Other symptoms of sensorineural hearing loss include:
- Difficulty following group conversations
- Muffled conversation sounds
- Inability to hear when background noise is present
- Difficulty hearing high-pitched sounds
- Balance problems
Sensorineural hearing loss vs. conductive hearing loss
Conductive hearing loss, one of the two main types of hearing loss, is brought on by the problem in the middle ear – ear drum or ossicles. The other type is sensorineural hearing loss, which is due to the damage in the inner ear. In some cases, a person may experience both types, which is considered mixed hearing loss.
There are several causes of conductive hearing loss, including the following:
- Ear wax buildup
- Ear infections
- Hole in the eardrum
- Glue ear – the middle ear begins to fill with fluid, which prevents the ear drum to move properly
- Inherited hearing loss
- Problem with the small bones in the ear
- Trauma to the head
- Ear surgery
Signs and symptoms related to conductive hearing loss include difficulty hearing others speak, symptoms related to an ear infection like pain, excess wax, tumor growth, and abnormal growth inside the ear leading to hearing loss.
The main difference between conductive hearing loss and sensorineural hearing loss is where the hearing loss occurs. Conductive hearing loss affects the middle ear, whereas sensorineural hearing loss affects the inner ear. In both types, though, damage is the primary cause of hearing loss.
Diagnosis and treatment options for sensorineural hearing loss
To diagnose sensorineural hearing loss, your doctor will perform a physical exam and review your medical history. During the physical exam, they will run tests to determine your level of hearing. They may also refer you for an MRI scan to check for any growths or abnormalities that could be contributing to your hearing loss.
In order to treat sensorineural hearing loss, your doctor must uncover the cause to target. Steroids are a common treatment as they can reduce inflammation and swelling. In some cases, a cochlear implant must be surgically inserted to help amplify sounds. Hearing aids, too, can aid in improving hearing.
Many patients can experience partial recovery from sensorineural hearing loss and roughly 3.6 percent will experience complete recovery. It’s important that you see your doctor at the first signs of any changes in your hearing in order to receive treatment sooner rather than later.