One Step Closer

This week we headed up to OHSU to meet with their Genetic Counselors. Our goal is to find the cause of Ben's hearing loss.

After giving our family history (no congenital hearing loss on either side), Ben was given a physical exam. He is right on track with his growth and is meeting all the age appropriate developmental markers. We told the counselors about Ben's ABRs and how his MRI and CT scans were normal.

That's where we were stopped short. The counselors had reports from the scans we had not yet seen. Apparently, Ben's MRI and CT scans were not normal. The doctor noted that Ben has enlarged vestibular aqueducts.

So, what does that mean? It's hard to explain, and we are still learning, but this is what we know so far:

• Vestibular aqueducts are narrow, bony canals that travel from the inner ear to deep inside the skull. The aqueducts begin inside the temporal bone, the part of the skull just above the ear.


• A vestibular aqueduct is considered enlarged if it is greater than 1.5 millimeters in size, roughly the diameter of the head of a pin.


• Scientists also are finding that five to 15 percent of children with sensorineural hearing loss, or hearing loss caused by damage to sensory cells inside the cochlea, have EVA.


• The presence of EVA can be a symptom of a genetic disorder called Pendred syndrome, a cause of childhood hearing loss. Approximately one-third of individuals with EVA and hearing loss have Pendred syndrome. With Pendred syndrome, the hearing loss is progressive, which means that a Ben could have less hearing over time.


• EVA may also be linked with balance problems.


• No treatment has proven effective in reducing the hearing loss associated with EVA or in slowing its progression.

Through my many hours Googleing and reading posts on my favorite cochlear implant connection, cicircle yahoo group, I have found that quite a few kids have EVA and receive cochlear implants. Whew! Although there can be some extra complications, implantation is possible.

After letting our new discoveries sink in for a bit, we are actually relieved. Often, children with congenital hearing loss have other physical or developmental challenges that surface as the child ages. With the findings of the EVA we can let many of our fears go.

Our next step is to have Genetics counselors at OHSU test Ben for Pendred Syndrome. We'll worry about that when the time comes.