case_images: PMC9610592_01
case_images: T2-weighted axial (a), T1-weighted sagittal (b), and T1-weighted contrast-enhanced sagittal magnetic resonance imaging (c) showing an intradural extramedullary mass at the C1 level (red arrow in (a),(b),(c)). The mass is hyperintense on T2 and isointense on T1 and is heterogeneously enhanced with gadolinium. Flow voids can be seen around the tumor (blue arrow) (a). T2-weighted sagittal MRI reveals a syringobulbia and syringomyelia (red arrow) (d). A scheme demonstrates the anatomical relationship between the tumor and the spinal cord (e). The tumor is an extramedullary mass with pial invasion or a subpial mass with extramedullary extension.
case_images: SNI-13-443-g001.jpg
case_images: PMC9610592_01_SNI-13-443-g001.jpg
case_images: F1
case_images: T2 MR studies; flow voids surrounded the tumor [Figure 1]. There was accompanying syringomyelia and syringobulbia, and there was no enhancement of the cyst/syrinx walls [Figure 1]. The right vertebral angiography documented a hypervascular C1 lesion fed by the C1/C2 radicular arteries [Figure 2].
case_images: Digital subtraction angiogram of the right vertebral artery showing dense tumor stain supplied by C1 and C2 radicular arteries (arrow).
case_images: SNI-13-443-g002.jpg
case_images: PMC9610592_01_SNI-13-443-g002.jpg
case_images: F2
case_images: T2 MR studies; flow voids surrounded the tumor [Figure 1]. There was accompanying syringomyelia and syringobulbia, and there was no enhancement of the cyst/syrinx walls [Figure 1]. The right vertebral angiography documented a hypervascular C1 lesion fed by the C1/C2 radicular arteries [Figure 2].
case_images: Intraoperative picture showing intradural extramedullary mass with pial invasion. It was red, vascular, and richly supplied by blood vessels (a). Oozing from the tumor was controlled by hemostatic materials (*). Total gross removal was accomplished (b).
case_images: SNI-13-443-g003.jpg
case_images: PMC9610592_01_SNI-13-443-g003.jpg
case_images: F3
case_images: Once the pial feeding vessels were coagulated, the tumor was circumferentially separated and resected en bloc [Figure 3].
case_images: A photograph of the surgical specimen shows large vascular spaces with the typical Staghorn appearance of the vessels.
case_images: SNI-13-443-g004.jpg
case_images: PMC9610592_01_SNI-13-443-g004.jpg
case_images: F4
case_images: Immunohistochemistry was positive for CD34 and CD31 and negative for Bcl-2; the Ki-67 index was 2%. In addition, many small and large blood vessels with characteristic Staghorn vasculature were evident throughout [Figure 4].
case_images: The postoperative T2-weighted magnetic resonance imaging 6 years after the operation shows complete tumor resection with a resolution of syringobulbia and syringomyelia.
case_images: SNI-13-443-g005.jpg
case_images: PMC9610592_01_SNI-13-443-g005.jpg
case_images: F5
case_images: Eight years later, he has exhibited no tumor recurrence [Figure 5].