Cerebellopontine angle tumors including schwannoma or meningioma are located around the vestibular nerve. In case of surgical removal, intraoperative neurophysiologic monitoring (IONM) modality such as brainstem auditory evoked potential (BAEP) could detect its neurologic function. We demonstrate 2 cases cerebellopontine surgery using BAEP an IONM modality. And we also suggest how to deal with ...

Hemifacial spasm can be caused by vascular compression of the facial nerve at the root exit zone from the brainstem. Several case reports suggest that narrowing of the cerebellopontine angle cistern caused by Paget's disease, abnormal elevation of the petrous bone caused by hyperplasia, or contralateral acoustic neurinoma may increase the chance of vascular compression of the facial nerve. Ther...

Both lipomas and dermoid cysts of the cerebellopontine angle are rare tumors. These tumors differ in their embryological origin but share similar features on imaging. Both of these congenital lesions can be found in the cerebellopontine angle (CPA), and symptomatic clinical presentation is dictated by the location of the lesion. This paper demonstrates a unique case in which a CPA lipoma was mi...

IMAGING FINDINGS Magnetic resonance imaging (MRI) of the brain showed a 1.5to 1.8-cm solid and cystic mass that enhances on T1 with contrast at the right cerebellopontine angle and extends into the internal auditory canal, abutting the cerebellum medially (Figure 1). On the day of treatment a stereolocalization MRI showed a mass in the right cerebellopontine angle extending into the right inter...

Vestibular schwannomas are the most common cerebellopontine angle tumors. These tumors commonly present with ipsilateral dysfunction of acoustic, vestibular, trigeminal, and facial nerves.1 Presentation of the vestibular schwannoma with contralateral facial nerve dysfunction is quite uncommon, and the contralateral facial paresis has been mentioned as a false localizing sign for posterior fossa...

hemangiopericytoma (hPC) is a rare tumor by definition and intracranial hPC makes up to less than one percent of all the intracranial tumors. It is a dural base tumor and its clinical features and radiological findings are similar to meningiomas. however, cerebellopontine angle hemangipericytoma had only been reported twice and would almost always be misdiagnosed. definite diagnosis is importan...

We report the case of a 71-year-old man who presented with a 2-year history of progressive left-sided hearing loss caused by a cerebellopontine angle mass lesion with classic imaging characteristics of a vestibular schwannoma. Vestibular schwannomas are typically diagnosed on dedicated MRI of the internal auditory canals obtained for asymmetric sensorineural hearing loss, as in this case. We re...