Abstract
Enlarged Vestibular Aqueduct (EVA) and Mondini’s dysplasia (incomplete partitioning type II) are entitites that have been fairly well described in the literature as potential causes of hearing loss in the young. However, it is uncommon for this condition to be detected bilaterally, especially so for both conditions to coexist bilaterally in the same patient. This is a brief description of a patient with the above bilateral condition with attached high resolution CT scan images of the temporal bone to illustrate the case.
A 38-year-old lady presented with progressive bilateral hearing loss. She had apparent normal hearing in both ears early in life but required a hearing aid in the right ear by the time she was 12 year old because her hearing in that ear had deteriorated. At that time, she recalls her left-sided hearing to be normal. However, she sustained head injury shortly after that, where she reported her left-sided hearing (which was previously normal) to abruptly deteriorate. For the past 20 years or so, she has managed well with her hearing aid but noticed her ability to communicate to progressively deteriorate in recent years. A recent audiogram noted bilateral profound hearing loss with a speech discrimination score of 30% on the right side, whereas there was no response on the left side ( Fig. 1 ).
A high-resolution computed tomography (CT) of the temporal bone was performed. It revealed bilateral enlarged vestibular aqueducts (EVAs) as well as bilateral incomplete partition type II (Mondini dysplasia) of the cochlea. The modiolus is also dysplastic bilaterally. However, all other inner ear features including the vestibules, semicircular canals, and oval and round windows are normal bilaterally ( Figs. 2 and 3 ).
