There are many different types of hearing aids out there, each designed to suit different types of hearing loss – and CROS system hearing aids are just one of the incredible technologies designed to help the hearing impaired listen in to the world again.
But what exactly is a CROS hearing aid? What do they do, and how do CROS system hearing aids work, exactly? Let’s take a closer look.
CROS hearing aids are specially designed for people who have little to no hearing in just one ear. Known as unilateral hearing loss or single-sided deafness, this hearing issue is quite common and can be caused by viral infections, Meniere's disease or head and ear injuries. The signs of hearing loss in one ear are similar to other hearing loss symptoms; however, trouble hearing consonants and understanding speech in a crowded, noisy environment may be particularly pronounced.
Because single-sided deafness only affects one ear, there are some quite specific requirements to help get the hearing of a person with this condition back up and running – and a regular hearing aid won’t do the trick, unfortunately. This is due to a phenomenon audiologists call the ‘head-shadow effect’: when a sound occurs on the side of the affected ear, the head literally blocks the sound from reaching the good ear. This affects higher-frequency sounds and makes understanding speech very difficult, as it can be very difficult to distinguish between consonants. For example, ‘hat’ and ‘cat’ may sound virtually the same.
That’s where CROS hearing aid technology comes in. CROS stands for Contralateral Routing of Signals, and these devices are designed specifically for people with unilateral hearing loss. Unlike traditional hearing aids, which send sound into the ear upon which they sit, with a CROS hearing aid, you wear a device on each ear, but only hear through one of them. The sound detected by the device worn on the ‘bad’ ear is transmitted to the device on the ‘good’ ear, removing the ‘head shadow’ effect and allowing a person to hear the sounds on both sides of their head in one ear.
CROS hearing aids are uniquely designed to help people with single-sided hearing loss. While they look like regular hearing aids, they are more like tiny microphones and transmitters, allowing people to hear sounds all around them despite losing hearing in one ear.
For a person experiencing single-sided deafness, the pros of a CROS hearing aid are clear. Their hearing has improved, and they can now hear from their ‘bad’ side. They no longer have to ask people to speak into their ‘good’ ear or be concerned they’ve missed something in conversation, especially in very noisy spaces. There are also broader social benefits – with the improvement in hearing, they may engage in more social interactions.
However, while this technology can be helpful, there can be some downsides to using a CROS hearing aid. They can take some getting used to, and as they don’t necessarily improve the localisation of sound (i.e. where the noise originates), they can’t always help a person know exactly where the sound they’re hearing is coming from. This can be particularly problematic if there’s a lot of background noise.
BiCROS hearing aids are similar to CROS hearing aids; however, they’re designed for people who have hearing loss in both ears but not to the same degree in each ear. This is called asymmetrical hearing loss. BiCROS stands for Bilateral Contralateral Routing of Signals, and it works very similarly to the CROS hearing aid system, but the device in your better-hearing ear will also be programmed for amplification, as a regular hearing aid would be.
As with all hearing aids, prices for CROS and BiCROS hearing aids will vary depending on many factors – your hearing needs, budget and lifestyle, as well as the style, brand and model, and technology built into your hearing devices. At Bay Audiology, CROS systems start at approximately $3,400 (including hearing aids, the microphone and receiver), and our clinicians will help you find the best option to suit you.