Intravestibular Lipoma An Important Imaging Diagnosis

Lipomas constitute 0.1% of all intracranial tumors.(1) Very rarely they are located in the cerebellopontine angle (CPA) or the internal auditory canal, and even less frequently they have been described in an intravestibular location.(2-4) These lipomas should not be treated surgically because their adherence to nerves and surrounding brain structures often leads to neurological deficits when surgical removal of the lesion is attempted. 1 Therefore, it is important to distinguish inner ear and CPA lipomas from more common tumors in the cerebellopontine region, such as acoustic neuromas, which are often treated surgically. Thus, noninvasive diagnosis by radiological imaging is crucial. We report herein a case of intravestibular lipoma that is associated with CPA lipoma and cystic cochleovestibular malformation (incomplete partition type 1) of the inner ear. Diagnostic magnetic resonance imaging (MRI) and computed tomographic (CT) characteristics of lipomas are discussed in detail. Furthermore, this unique combination of intravestibular lipoma with cystic cochleovestibular malformation provides more understanding of the pathophysiologic characteristics of these rare tumors.