Fig 5.

Patient 8. Axial postgadolinium T1 (A and C) and axial T2 FLAIR (B) MR images demonstrate an irregularly enhancing, T2 FLAIR hyperintense mass involving the right lateral pons and expected origins and intracranial course of both the right facial (A) and the trigeminal (B and C, arrow) nerves. Enhancement also extends into the right internal auditory canal along its anterior and superior aspect where the extra-axial facial nerve courses (A, arrow). Asterisk (A) marks the approximate site of biopsy. D, Hematoxylin-eosin-stained intraoperative smear preparation (original magnification ×10) demonstrates a population of neoplastic astrocytes with nuclear pleomorphism and numerous mitotic figures. A vessel with extensive budding and endothelial proliferation is present (arrow). Pathologic diagnosis was a glioblastoma, WHO grade IV. This patient presented with right facial numbness and weakness, but no clinical evidence of vestibulocochlear nerve involvement until later in the disease course.