Fig. 2

A 55-year-old woman presented with numbness and weakness of limbs and was diagnosis with basilar invagination. A and B: Preoperative sagittal T1-weighted and T2-weighted MR images show intraspinal tumor in the upper cervical spine. C and D: Preoperative sagittal CT scan and CT angiography of the upper cervical spine. E: Intraoperative fluoroscopy with locating pin. F: Intraoperative tumor exposure after spinal durotomy. G: Duraplasty after tumor excision. H: Posterior fusion and stabilization. I and J: Postoperative sagittal T1-weighted and T2-weighted MR images show that intraspinal tumor was resected and the spinal cord was sufficient decompressed. K and L: Sagittal T1-weighted and T2-weighted MR images at a follow-up of 3 months postoperatively and the patient could walk well after the operation