Foramen magnum/petroclival meningioma – immediate postoperative radiosurgery for residual

SKULL BASE REGION	Foramen magnum
HISTOPATHOLOGY	Meningioma, WHO grade 1
PRIOR SURGICAL RESECTION	Yes
PERTINENT LABORATORY FINDINGS	N/A

Case description

A 63-year-old woman presented with a worsening headache and was found to have a 4-cm petroclival meningioma centered on the lower third of the clivus with compression of the brainstem and a 360-degree encasement of the right vertebral artery ( Figure 11.55.1 ). The patient underwent subtotal resection through a suboccipital retrosigmoid approach with an estimated 90% tumor resection. Residual tumor was left at the foramen magnum, where the vertebral artery was encased by the tumor. Postoperatively, she developed a right hypoglossal nerve palsy. Follow-up imaging demonstrated rapid regrowth of the tumor residual at the foramen magnum, with recurrence of brainstem compression ( Figure 11.55.2 ). This recurrent tumor was resected through a far lateral approach 29 months after the initial operation. The surgical goal of brainstem decompression was achieved with residual tumor left on the foramen magnum and vertebral artery ( Figure 11.55.3 ). She then underwent stereotactic radiosurgery (SRS) of the residual tumor about 3 months after surgery ( Figure 11.55.4 ).