What is Microtia and Aural Atresia?
Microtia and aural atresia are developmental problems of the external ear and ear canal (see image on the right). Microtia refers to the underdevelopment or lack of the external ear, while aural atresia is the absence of the ear canal. This birth deformity is usually one sided (unilateral) but occasionally can occur with both ears (bilateral). Most people understand that bilateral hearing loss is a profound handicap, but many are unaware of the significant handicap caused by unilateral hearing loss and how it affects a child’s ability to learn. These children are classified as educationally disabled by the Individuals with Disabilities Educational Act of 2004, 602(3).
Most people assume that having one ear is like having only one eye. If we cover one eye, we can see clearly out of our other eye. We are able to read, watch instructional videos, and focus on objects both near and far with the same clarity. The only consequence is a limited field of vision and reduced depth perception. We therefore assume that those born with only one ear are only limited in the volume of the sound that they hear; this is not the case.
Complications of Aural Atresia and Microtia
A person born with unilateral microtia and aural atresia is unable to localize sound. If they are walking down a busy street and a car horn sounds to alert them of impending danger, they are unable to determine the direction of the sound. Likewise, when their mother or father calls their name in a crowded environment, they are unable to determine the location of their parent.
More problematic, is the inability to differentiate between sounds. Those with normal hearing in both ears can easily distinguish between multiple sounds. If we are sitting in a noisy cafeteria with two friends at our table, we are able to focus on one person speaking and can ignore the other distracting sounds around us. We even have the ability to tune out the conversation between friends at our own table to focus on a conversation at another table. Children with unilateral microtia and aural atresia do not have this ability. All of the sound occurring around them comes into one ear and competes equally for their attention. In the classroom setting these children have difficulty hearing the teacher’s words because of other competing sounds in the room. These sounds could be the other children whispering behind them, the air conditioner blower fan, the lawnmower outside the window, or a floor buffer out in the hallway. All of these sounds compete with the teacher’s voice making it very difficult for the child to focus and learn.
Effects of Unilateral Hearing Loss on Education
Children with unilateral hearing loss have been found to have increased rates of grade failures, have need of additional educational assistance, and have perceived behavioral issues in the classroom.1,2 Speech and language delays are also common. As a result, these children usually require an individual educational plan (IEP). This creates three main problems. First, the child is limited in developing their full potential both in classroom learning and socialization. Second, their speech skills are often limited requiring time away from the classroom to attend school sponsored speech therapy sessions. Third, added costs that must be absorbed by the school system to cover the individualized educational plan and all of the added professional services (including the speech therapist).
About the Solution
Recent studies have shown significant improvements in the hearing acuity and classroom performance of children with microtia and aural atresia who are fitted with a specialized bone conducting hearing device called a BAHA, or Pronto Pro. This device is significantly different than a normal hearing aid. A normal hearing aid fits within the ear canal and amplifies the sound. Children with microtia and aural atresia are born without an ear canal so traditional hearing aids cannot help them. Fortunately, these children often have a normal cochlea embedded deep within the temporal bone, which would allow them to hear if the sound waves could reach it. The bone conducting hearing device transfers sound waves into vibrations. It is held against the bone immediately behind the malformed ear with a soft headband and the vibrations from the device can be perceived as sound by the cochlea embedded deep within the bone. The bone conducting hearing device allows them to hear out of both ears, localize the direction of sound, and focus more clearly on the teacher’s words through other competing sounds in the classroom. Having two ears allows them to learn more effectively. Having two ears helps to provide safety in a noisy and confusing world.
A problem most of our children with microtia and aural atresia encounter is that the BAHA hearing device is not covered by most insurance plans. When purchased new, these devices can cost between $4,000 and $5,000. Many families with children in elementary school do not have the resources to obtain this device.
2 Ears 2 Learn is a non-profit organization created to help with this problem. We collect used BAHA and Pronto Pro sound processors from audiologists, otolaryngologists, and from patients who no longer need them. We have them refurbished and then provide them to children with microtia and aural atresia at no cost. Our target group is children between 4 and 10 years of age.
We strive to educate elementary school teachers, nurses, therapists, and administrators about the significant learning handicap caused by microtia and aural atresia, and provide materials for them to share with the parents of affected children. We want to help these parents understand why their child is falling behind, and help them find out how to obtain a refurbished sound processor for their child.
We also work with each state’s Interagency Coordination Council for Special Education to help them understand that these children are protected by the Individuals with Disabilities Education Act (IDEA 602(3)). We can help each state meet their requirements as mandated by the education act, by providing a hearing assist device to these affected children. States and school districts can then educate these children more effectively, resulting in fewer IEP’s, fewer grade failures, and less strain on classroom teachers.
Finally, we stive to properly educate state insurance boards about the difference between a bone anchored sound processor and a regular hearing aid. We hope to thereby restrict insurance companies from denying coverage for these helpful devices for children born with microtia and aural atresia.
- Lieu J. Speech-language and educational consequences of unilateral hearing loss in children. Arch Otolaryngol Head & Neck Surg. 2004; 130(5):524-530.
- Lieu JE, Tye-Murray N, Fu Q. Longitudinal study of children with unilateral hearing loss. Laryngoscope. 2012;122(9):2088-2095.
- Christensen l, Richter GT, Dornhoffer JL. Update on bone-anchored hearing aids in pediatric patients with profound unilateral sensorineural hearing loss. Arch Otolaryngol Head & Neck Surg. 2010; 136(2):176-177.