[Acoustic neurinoma located exclusively in cerebellopontine angle cistern ("cisternal" acoustic neurinoma): a case report].
This is a case report of acoustic neurinoma which was located exclusively in the cerebellopontine angle (CPA) cistern and which did not extend into the internal auditory meatus ("cisternal" acoustic neurinoma). The 43-year-old female patient had signs of the left trigeminal nerve impairment including left face neuralgia. However, she did not have any neurootological symptom. No abnormal bony changes in the internal auditory meatus (IAM) were found by high-resolution bone-window CT. MRI showed a left CPA tumor of 25mm not extending into the IAM. The tumor was totally removed by the lateral suboccipital approach. It originated from the vestibular nerve medial to the porus acusticus and was located exclusively in the CPA cistern. No tumor extension into the IAM was confirmed. The cochlear nerve was involved in the tumor capsule and could not be preserved. The pathological diagnosis was that it was a neurilemmoma. Early diagnosis of "cisternal" acoustic neurinoma is difficult because it does not show neurootological symptoms in the early stage. The lateral suboccipital approach is appropriate for the removal of a "cisternal" acoustic neurinoma. However, in spite of the good preoperative hearing, the preservation of hearing is difficult because of the large tumor size.
Yamakami
I
I
Department of Neurosurgery, Chiba University School of Medicine.
Oka
N
N
Yamaura
A
A
D002528:Cerebellar Neoplasms / Q000175:diagnosis / Q000601:surgery*; D002530:Cerebellopontine Angle; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D009464:Neuroma, Acoustic / Q000175:diagnosis / Q000601:surgery*; D014057:Tomography, X-Ray Computed