by Neil Bauman, Ph.D.
Not much was known about enlarged vestibular aqueducts (EVA) when I first wrote about it in 2002. Back then, it was called Large Vestibular Aqueduct Syndrome (LVAS). Now it is more-commonly referred to as EVA, but it is the same condition.
In the intervening years, researchers have done a number of studies on EVA and related conditions, such as Pendred syndrome, to try to ferret out exactly what causes the hearing loss, what genes are involved, etc, with an eye to finding an effective treatment for this condition.
One of the things that bothered researchers about EVA was that increasing hearing loss did not correlate with the increasing size of the vestibular aqueducts. Thus, it became obvious there must be some other mechanism, not the large vestibular aqueducts themselves, that caused the hearing loss.
The latest research focused on genetics—specifically on the SLC26A4 gene and its role in the expression of the pendrin protein and how that affects hearing. You can learn more about these latest findings in my recently-revised, comprehensive article on EVA.