European Radiology

, Volume 14, Issue 7, pp 1169–1173 | Cite as

Exophytic pilocytic astrocytoma of the brain stem in an adult with encasement of the caudal cranial nerve complex (IX–XII): presurgical anatomical neuroimaging using MRI

  • Indra YousryEmail author
  • Alexander Muacevic
  • Vlad Olteanu-Nerbe
  • Thomas P. Naidich
  • Tarek A. Yousry


We describe a rare case of adult pilocytic astrocytoma in which exophytic growth from the brain stem presented as a right cerebellopontine angle mass. An initial MRI examination using T2- and T1-weighted images without and with contrast suggested the diagnosis of schwannoma. Subsequent use of 3D CISS (three-dimensional constructive interference in steady state) and T1-weighted contrast-enhanced 3D MP-RAGE (three-dimensional magnetization prepared rapid acquisition gradient echo) sequences led to the diagnosis of an exophytic brain stem tumor, documented the precise relationships of the tumor to cranial nerve VIII, revealed encasement of cranial nerves IX–XII (later confirmed intraoperatively), and provided the proper basis for planning surgical management.


Pilocytic astrocytoma MRI Cerebellopontine angle Caudal cranial nerve complex 


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Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  • Indra Yousry
    • 1
    Email author
  • Alexander Muacevic
    • 2
  • Vlad Olteanu-Nerbe
    • 2
  • Thomas P. Naidich
    • 3
  • Tarek A. Yousry
    • 1
  1. 1.Department of NeuroradiologyKlinikum Grosshadern, Ludwig-Maximilians UniversityMunichGermany
  2. 2.Department of NeurosurgeryKlinikum Grosshadern, Ludwig-Maximilians UniversityMunichGermany
  3. 3.Department of Radiology, Section of NeuroradiologyMount Sinai HospitalNew YorkUSA

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