What is Sensorineural Hearing Loss

Sensorineural hearing loss

What is sensorineural hearing loss and how does it affect your life? This common, often permanent hearing impairment stems from issues within the inner ear or auditory nerve. This guide will walk you through its symptoms, causes, and treatments that are reshaping the lives of those with impaired hearing.

What we’ll cover

• The most common type of permanent hearing loss, how it affects the hair cells in the cochlea or the auditory nerve, and how it can lead to cognitive decline, depression, and increased risk of falls.
• Causes of sensorineural hearing loss, from age-related degeneration to exposure to loud sounds and genetic factors, with the condition presenting on a spectrum from mild to profound hearing impairment.
• Advanced treatments for sensorineural hearing loss include modern hearing aids with features like AI and Bluetooth connectivity, bone conduction devices, cochlear implants for severe cases, and preventive measures to safeguard against further hearing degradation.

Understanding Sensorineural Hearing Loss

Sensorineural hearing loss is caused by damage to the hair cells in the cochlea (the spiral cavity of the inner ear) or the auditory nerve. This type of permanent hearing loss, which can affect one ear or both, is the most common, affecting nearly 38 million adults in the United States and 1.5 billion people worldwide.

The impact of untreated sensorineural hearing loss extends beyond hearing itself. It can result in serious health issues, such as:

• dementia
• cognitive decline
• depression
• social isolation
• an increased risk of falls

More than 90% of hearing loss in adults is due to damage in the inner ear or auditory nerve, and hearing aids can significantly enhance hearing ability for these individuals.

Causes Behind Sensorineural Hearing Loss

Sensorineural hearing loss can be caused by a variety of factors. It is a complex condition with diverse underlying causes. Aging is a significant factor, with the prevalence of hearing loss increasing with each passing decade of life. Exposure to loud sounds, whether from a one-time event or consistent noise, can result in noise-induced sensorineural hearing loss.

In some cases, sensorineural hearing loss is present at birth due to genetic factors, particularly the GJB2 gene, which encodes connexin 26, a protein that plays a significant role in converting sound waves to electrical signals for the brain’s interpretation.

Certain medications and medical conditions, such as Ménière’s disease, autoimmune disorders, and vestibular schwannoma, have also been linked to sensorineural hearing loss.

Symptoms: From Mild to Serious Hearing Loss

Individuals with sensorineural hearing loss can find it difficult to follow conversations in noisy environments, especially when there are loud noises. 

Mild sensorineural hearing loss can manifest as issues with clarity when there’s background noise or in group conversations.

However, sensorineural hearing loss isn’t static. It can progress over time, especially when related to age or genetic factors. As the condition worsens, the challenges in understanding normal speech become even more significant, impacting both everyday conversations and professional or educational interactions.

Inner Ear and Auditory Nerve Function

A deeper understanding of sensorineural hearing loss requires a look at the biology of hearing. The cochlea, with its fluid and sensory epithelium composed of hair and supporting cells, is instrumental in hearing. Potassium ions flowing into the hair cell in the cochlea cause depolarization, which is necessary for converting vibrations into electrical impulses.

These impulses then travel via the auditory nerve to the brain, where they are interpreted as sound. When there are abnormalities in the auditory nerve or damage to the hair cells in the cochlea, the ability of the brain to receive sound signals can be impeded, resulting in sensorineural hearing loss.

Imagine the shock of waking up one day to find your hearing significantly reduced, or even gone entirely. This is the reality of sudden hearing loss, specifically sudden sensorineural hearing loss (SSHL), a medical emergency characterized by rapid hearing loss within a 72-hour window. Potential triggers for SSHL include:

• Injury
• Illness
• Exposure to loud noise
• Pathogens like COVID-19

Symptoms of severe SSHL can manifest suddenly and can be due to various factors, including viral infections, trauma, or prolonged exposure to loud sounds. Fortunately, immediate treatment, often with oral steroids or injections, can lead to full or partial restoration of hearing, especially if initiated quickly after the onset of the loss.

The Spectrum of Sensorineural Hearing Impairment

Sensorineural hearing loss isn’t a one-size-fits-all condition; it exists on a spectrum, and mixed hearing loss is another type of hearing impairment. For those with mild sensorineural hearing loss, trouble following conversations in noisy environments is a common issue, which can lead to social isolation.

As the condition progresses to moderate hearing loss, individuals often face significant challenges in understanding normal speech, even with the use of hearing aids. At its most severe, sensorineural hearing loss can result in an inability to hear most conversations, with affected individuals often relying on lip reading or sign language for communication.

Diagnosing Sensorineural Hearing Conditions

Diagnosing sensorineural hearing loss involves multiple steps. It starts with a physical exam of the ears to check for conditions like:

• inflammation
• fluid
• earwax buildup
• eardrum damage

This helps differentiate sensorineural from conductive hearing loss.

Following this, initial screening may involve tuning fork tests, such as the Weber and Rinne tests, to assess sound perception and compare air and bone conduction. Audiometry tests are then conducted, culminating in an audiogram that shows the lowest volumes heard at different sound frequencies. These evaluations, conducted by audiologists or hearing instrument specialists, are crucial for the correct diagnosis and subsequent treatment of sensorineural hearing loss.

Innovative Hearing Aids: Technology for Better Hearing

Hearing aids have come a long way from the bulky, problematic devices of the past. Modern hearing aids now come equipped with advanced features like:

• Rechargeable batteries
• Bluetooth connectivity
• Water resistance
• Artificial intelligence, which automates sound quality adjustments in different environments

These innovative hearing aids are capable of dialing in on specific sounds and enhancing the frequencies associated with a user’s particular hearing loss, without unnecessarily amplifying other sounds. They also feature advancements in nanocoating and repellent technologies, making them more durable against wear and tear from water, wax, and moisture.

Customizable Hearing Solutions

Advanced digital technology has made it possible for hearing aids to be precisely customized to a user’s hearing needs. These customizable hearing solutions provide a personalized listening experience by adjusting the relationship between soft sounds to loud sounds for individual comfort.

Moreover, modern hearing aids are complemented by smartphone apps which offer users the ability to easily personalize sound settings to their preference. This level of customization makes for a more tailored and effective hearing solution.

Bone Conduction Devices

For some, bone conduction devices offer an alternative to traditional hearing aids. These devices work by amplifying sound through vibrations that are transmitted to the bones in the skull, directly stimulating the inner ear and bypassing the outer and middle ear.

This technology can be a game-changer for those unable to use conventional hearing aids.

Smart Features in Modern Hearing Aids

Artificial intelligence isn’t just for self-driving cars and voice assistants; it’s also enhancing the functionality of modern hearing aids. Artificial intelligence enables hearing aids to recognize the user’s environment and automatically adjust their settings for the best sound quality.

Furthermore, modern hearing aids are equipped with the following features:

• Bluetooth connectivity
• Internet connectivity
• Improved user interactivity
• Personalization

These smart features bring a new level of sophistication and convenience to hearing aid technology.

Cochlear Implants: A Leap Forward for Severe SNHL

While hearing aids can provide significant hearing improvements for individuals with mild to moderate sensorineural hearing loss, those with profound hearing loss may not find them sufficient. In such cases, cochlear implants can be a game-changer. These devices bypass damaged hair cells to directly stimulate the auditory nerve, significantly improving the capacity for communication, language development, and educational access.

Within 3 to 6 months of using a cochlear implant, most individuals experience considerable advancements in speech comprehension, even in the absence of visual cues. While some adults may begin with a unilateral cochlear implant complemented by a hearing aid, children with severe bilateral hearing loss often receive two implants simultaneously to aid in language development.

Strategies for Managing Life with Hearing Loss

Living with hearing loss can be challenging, but some strategies can help. Simple actions like positioning oneself to face the speaker and choosing quieter, well-lit environments can improve communication. Residents in many states can even get an internet-based Captel phone for free with confirmation from a doctor or audiologist, aiding communication.

Modern hearing aids offer several advanced features, including:

• Integration of sensors and artificial intelligence to track body and brain health
• Direct streaming of audio from devices like televisions and radios, providing a more personalized listening experience
• Compatibility with closed captioning for TV, movies, and online videos, which can significantly aid individuals with sensorineural hearing loss in understanding spoken content.

Prevention Tactics: Safeguarding Your Hearing

While treatment options for sensorineural hearing loss have significantly advanced, prevention remains the best medicine. Noise-induced hearing loss accounts for an estimated 16% of disabling hearing loss among adults globally. This can be prevented by using earplugs or noise-canceling headphones, avoiding noisy places, and keeping volume levels down when using earbuds or headphones.

Earplugs or earmuffs should be used as hearing protection devices when exposure to loud sounds can’t be avoided or reduced. Regular hearing checks by a licensed audiologist or qualified professional are also important, especially if there are concerns about potential hearing loss in one or both ears.

Differentiating Hearing Loss Types

Understanding whether hearing loss is sensorineural or conductive is crucial, as treatment options vary significantly. Conductive hearing loss is a condition where sound waves cannot be efficiently transmitted from the middle or outer ear to the inner ear.

Common causes of conductive hearing loss include obstructions or issues within the middle or outer ear. Clinical methods like the Weber and Rinne tests are used to differentiate between sensorineural and conductive hearing loss types. Understanding the type of hearing loss is the first step toward an effective treatment plan.