Single-sided deafness: What you need to know

Single Sided Deafness (SSD), or significant hearing loss in one ear, affects 60,000 people each year in the United States alone.

According to a study by doctors in the UK, awareness about SSD is limited even in the medical community: “Awareness of SSD and its symptoms is inevitably low... This results in limited or delayed referral and diagnosis, and often the failure to provide support for clients.” So what is Single Sided Deafness and which unique challenges do people with SSD face? Read the facts below.

What is single sided deafness?

Single Sided Deafness (SSD) involves significant damage to hearing in one ear. People with SSD have reduced speech intelligibility for several reasons: The inability to separate background noise from the signal of interest, the lack of binaural summation effect, and difficulties hearing the signal of interest coming from the side of the deaf ear.

How are people with single sided deafness affected by the condition?

People with Single Sided Deafness (SSD) have reduced speech intelligibility, which can lead to problems at work and at home. In one UK study, 24 percent of people with SSD had to give up work. Others reported feelings of social isolation and exclusion. People with SSD often struggle to hear sounds that occur on the side of the deaf ear and have difficulties in challenging listening environments.

Is there a cure for single sided deafness?

While there is no cure for SSD, there are options available to help those who suffer from it. The three most common solutions are:

CROS: These systems wirelessly transmit sound from the deaf ear to the better ear via a transmitter, which is placed behind the deaf ear. The transmitter picks up sound and wirelessly transmits it to a receiver hearing aid on the normal-hearing ear. This solution is discreet and requires a non-invasive fitting procedure.

BiCROS: Similar to CROS, but is made for those who are deaf in one ear and hearing impaired in the other ear. Here, the receiver hearing aid also amplifies sound on the better ear, so that it matches the degree of hearing loss in this ear.

BAHA: This system is a semi-implantable bone-anchored hearing device that transfers sound from the deaf side to the cochlea using bone conduction. This is installed via a surgical procedure and is more visible than CROS or BiCROS systems.

How do cros and bicros systems help people with single sided deafness?

CROS and BiCROS system help people with SSD to better locate sounds and distinguish background noise. In a recent study from Denmark, researchers found that the specific situations in which the test subjects rated the improvement with CROS to be the most significant were when following a conversation in the presence of background noise, when having a conversation while driving a car and when participating in a group conversation.


WIDEX CROS can be fitted with any hearing aid in the DREAM range either as a CROS or BiCROS option to increase awareness and listening.

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