Introduction:

CROS (Contralateral Routing of Signals) hearing aids are a type of assistive device designed for individuals with significant hearing loss or "unaidable" hearing in one ear. These devices transfer sound from the ear with no useful hearing to the better-hearing ear. If one ear has normal or manageable hearing while the other is severely impaired, a CROS system can help balance your hearing experience.

What Is a CROS System?

A CROS system is a form of binaural hearing aid configuration where one device functions as a full hearing aid while the other is essentially a microphone. The microphone picks up sounds from the poorer-hearing side and wirelessly transfers them to the hearing aid in the better ear. CROS hearing aids are commonly available in Receiver-in-Canal (RIC) styles, which are discreet and comfortable to wear.

Who Really Needs a CROS System?

CROS systems are designed for individuals with single-sided deafness (SSD) or asymmetric hearing loss. For example:

People with normal hearing in one ear and unaidable hearing in the other.

Those who experience minimal benefit from traditional hearing aids in their poorer ear due to a severe hearing loss or poor speech understanding.

The goal of a CROS system is to provide a solution for individuals who struggle to hear sounds coming from the side of the unaidable ear, allowing them to maintain awareness of their surroundings more effectively.

How Many Options of CROS Exist?

There are two main types of CROS systems:

CROS Model: This option is ideal for people with normal hearing in one ear and unaidable hearing in the other. The device in the poorer ear transfers sound to the better ear without amplifying it.

BiCROS Model: This option is suitable for people with hearing loss in both ears, where one ear is more severely affected than the other. In this case, both ears receive amplification, but the poorer ear primarily functions as a microphone for sound transmission to the better ear.

Why Go for a CROS System Over Hearing Aids in One Ear?

Some may wonder why they can’t just wear a hearing aid in the poorer ear and leave the better ear untreated. The answer depends on factors like:

Severity of Hearing Loss: Severe hearing loss in one ear can make conventional hearing aids uncomfortable, producing distortion, and providing little benefit.

Speech Understanding Ability: If speech recognition is poor in the affected ear, a hearing aid may just amplify noise without improving clarity.

Previous Experience: If you’ve used a hearing aid in your poorer ear before without significant benefit, this could indicate that a CROS system may be more appropriate for you.

When Does It Become an Absolute Necessity?

CROS systems are particularly useful for people who face challenges in complex auditory environments, such as:

Difficulty localizing where sounds are coming from.

Trouble hearing in group conversations or noisy environments.

Inability to hear people speaking from the side of their poorer ear.

Missing alerts, name calls, or important sounds when the better ear is occupied (e.g., during phone calls).

Do CROS Hearing Aids Actually Benefit Users?

The benefits of CROS hearing aids depend on several factors, including the degree of hearing loss in the better ear and the specific environments where you need support.

CROS systems are most beneficial for people who have difficulty hearing in noisy situations, group settings, or when sounds originate from the poorer ear's side.

They may improve sound localization, attention to alerts, and can make it easier to follow conversations when the better ear is engaged elsewhere.

However, it’s essential to note that CROS hearing aids won’t fully replicate the experience of hearing with two functioning ears.

Individuals with CROS systems often report the most improvement in environments where they previously struggled, such as crowded places or meetings, but may still encounter limitations in complex auditory environments.

Conclusion:

CROS hearing aids offer a valuable solution for those with single-sided or asymmetric hearing loss. By rerouting sounds from the poorer ear to the better ear, they allow for greater situational awareness and improved hearing in challenging environments.

While they may not restore full binaural hearing, they can significantly enhance quality of life for those struggling with single-sided hearing challenges.

Be sure to consult with a qualified audiologist to determine if a CROS system is right for you, and to explore the latest advancements in technology that can further enhance your experience.

Sahil Singh

Head Audiologist – Faridabad Speech & Hearing Centre

To know more: WhatsApp 8700723994