title: Typical Symptoms of Normal-Pressure Hydrocephalus Caused by Choroid Plexus Papilloma in the Cerebellopontine Angle.
abstract: BACKGROUND
  Choroid plexus papillomas (CPPs) are rare benign intracranial tumors. We report a rare case of CPP manifesting with typical symptoms of normal-pressure hydrocephalus rather than obstructive hydrocephalus.
  
  
  METHODS
  A 45-year-old woman presented with a 6-year history of headache and typical symptoms of normal-pressure hydrocephalus, including gait disturbance, urinary incontinence, and cognitive dysfunction, in addition to the more common symptoms of CPP, such as lower cranial nerve dysfunctions and ataxia. The CPP arose from the right lateral recess of the fourth ventricle and extended to the cerebellopontine angle. Magnetic resonance imaging did not show any radiographic evidence of obstruction of aqueduct, foramen of Magendie, or foramen of Luschka on the contralateral side. We speculated that hydrocephalus was associated with cerebrospinal fluid overproduction by the CPP originating from the choroid plexus of the lateral recess and extending laterally into the cerebellomedullary fissure (CMF). Surgical excision was performed with a trans-CMF approach. The symptoms of normal-pressure hydrocephalus disappeared. In addition to improved clinical symptoms, radiographic findings showed mitigation of ventricular dilatation.
  
  
  CONCLUSIONS
  The hydrocephalus was of a communicating type and caused by CSF overproduction. The lateral route of the trans-CMF approach is useful for the dissection of tumors that extend into the unilateral cerebellomedullary cistern through the CMF. This approach not only enables sufficient exposure for resection but also avoids damage to the surrounding structures.
authors.affiliation: Department of Neurosurgery, Faculty of Medicine, Saga University, Saga, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ito
authors.affiliation: Department of Neurosurgery, Faculty of Medicine, Saga University, Saga, Japan. Electronic address: nakahara@cc.saga-u.ac.jp.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Nakahara
authors.affiliation: Department of Neurosurgery, Faculty of Medicine, Saga University, Saga, Japan.
authors.forename: Masatou
authors.initials: M
authors.lastname: Kawashima
authors.affiliation: Department of Neurosurgery, Faculty of Medicine, Saga University, Saga, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Masuoka
authors.affiliation: Department of Neurosurgery, Faculty of Medicine, Saga University, Saga, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Abe
authors.affiliation: Neuroscience Center, Fukuoka Sanno Hospital, Fukuoka, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Matsushima
mesh_terms: D002528:Cerebellar Neoplasms / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery; D002530:Cerebellopontine Angle / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D006850:Hydrocephalus, Normal Pressure / Q000000981:diagnostic imaging / Q000209:etiology* / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods; D020288:Papilloma, Choroid Plexus / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery; D015898:Tomography Scanners, X-Ray Computed
keywords: CSF overproduction; Choroid plexus papilloma; Normal-pressure hydrocephalus; Trans-CMF approach