Fig. 3

Intraoperative photomicrograph. a The trigeminal nerve (thick arrow) and the tumor (thin arrow) are seen under the tentorium of the cerebellum (dashed line arrow), respectively. b Ampliative Dorello’s canal (dashed line arrow) was stripped to expose the tumor (thin arrow) which was located under the trigeminal nerve (thick arrow). c The tumor (thin arrow) was located between the trigeminal nerve and the basilar artery (thick arrow). The tumor had no relationship with the dura but was strongly adherent to the pons and the basilar artery. d A subtotal removal was performed, and the trigeminal nerve (thin arrow), the pons (dashed line arrow), and the basilar artery (thick arrow) were seen