Tuesday, September 26, 2006

CT results are in- we have an answer....

Lily has enlarged vestibular aqueduct syndrome. I was convinced that we would never know the cause of her hearing loss. Will be adding more info as I learn more....

Here is a clearer explanation:
http://www.hearinglosshelp.com/articles/lvas.htm?zoom_highlight=lvas

What I was specifically told was that Lily has "enlarged vestibular aqueducts with mild cochlear dysplasia".

This is an autosomal recessive non-syndromic genetic disorder. I didn't take AP Biology in high school :P but this is my basic understanding: Chris and I are both recessive carriers of the gene that causes EVAS (and I am also finding info that she may have something called Mondini dysplasia). For each of our offspring, there is a 25% chance that we would have a child with hearing loss, a 50% chance of having a child with no hearing loss but is also a recessive carrier, and a 25% chance of having a child with no hearing loss and no recessive gene.


What is the vestibular aqueduct?
The vestibular aqueduct is the bony canal that links the inner ear with the fluid that surrounds the brain. In adults the vestibular aqueduct is narrow and shaped like the letter 'J'. However, when a baby is in the womb the vestibular aqueduct starts off being short, wide and straight before it develops, before birth, into a longer, narrower, J-shaped tube. The terms 'enlarged', 'wide' or 'dilated' refer to vestibular aqueducts that have not developed fully, and remain short and wide. In this document we will refer to an enlarged vestibular aqueduct.
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How does an enlarged vestibular aqueduct affect hearing?
An enlarged vestibular aqueduct can cause progressive or fluctuating deafness. (In other words, deafness that gets worse over time or changes from one level to another and back again.)

No one is quite sure why this happens. One explanation is that an enlarged vestibular aqueduct may allow the various pressure changes in the fluid around the brain to pass through to the inner ear (known as the cochlea), possibly affecting the hearing system.

The type of deafness usually associated with an enlarged vestibular aqueduct tends to be worse in the higher frequencies and usually affects both ears. Some people also experience a feeling of dizziness and imbalance (vertigo), and a general lack of co-ordination. It is difficult to know if your child's deafness will change over time or stay the same. However, the specialist may suggest that your child avoids certain sports, including contact sports and those that involve being exposed to changes in pressure (such as scuba diving). This is because it is thought that severe changes in pressure or a minor head injury can lead to an increase in deafness in children with an enlarged vestibular aqueduct.

2 comments:

Kate Ryan said...

Just wanted to say that your daughter is PRECIOUS and all will be fine! My daughter is 12 and has a mod to sev hearing loss, wears hearing aids, and speaks wonderfully. PLEASE continue to consult AGBell, auditory-verbal, etc. I PROMISE you it is ALL worth it! I can SO relate to the experience of being around kids the same age and realizing how delayed our own kids speech may be...in the early years. I recently met a woman whose 3 year old daughter just received two cochlear implants. She is going through the same thing. I tell her, and I'll tell you, too---one day you will chuckle when your child's teacher sends home a note saying she talks too much in class, or one day you will tell your daughter to please be quiet, then chuckle thinking about how silly that seems after trying for so long to get her to talk. My point is this: the road is not easy, and there are many twists and turns...but it is THE MOST BEAUTIFUL ROAD IN THE WORLD! It is SO worth it! Hang in there! :) I will check back and write more later. I know as well as anyone how important it is for parents of newly diagnosed kids to hear from parents of older kids--it is the ONLY thing that kept me encouraged! Seeing older kids do SO WELL---I KNEW it would be possible for my child, too! and it was! :) God bless!

AOB said...

Thanks so much for your encouragement. It does help to hear about older children with hearing loss who are doing well.