PMC8195662_01
Cervical spine X-ray images. The left oblique view (a) revealed the left C5-6 and C6-7 stenoses (arrow). Anteflexion (b) and retroflexion (c) did not show cervical spine instability.
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fig1
Noncontrast-enhanced magnetic resonance images. In horizontal sections (a, b), cervical disc herniation happened in the same region as the left C5-6 and C6-7 stenoses (arrow). At the C1-2 level, an intradural extramedullary cystic lesion existed in the right side of ventral cervical spinal cord, which severely compressed the spinal cord ((c) sagittal, (d) horizontal, and (e) coronal, arrow).
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fig2
Furthermore, an intradural extramedullary cystic lesion on the right side of ventral cervical spinal cord at the C1-2 level severely compressed the spinal cord (Figure 2).
Contrast-enhanced magnetic resonance imaging of the cervical spine. Because a cyst was partially enhancing, a tumor lesion was not identifiable ((a) sagittal, (b) horizontal, (c) coronal, arrow).
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fig3
A cyst was partially enhancing in contrast-enhanced MRI, and a tumor lesion was, therefore, not identifiable (Figure 3).
Noncontrast-enhanced computed tomography (CT) and CT myelography. Foraminal stenosis of the left C6-7 intervertebral foramen was identified in the horizontal section ((a, b), arrow). CT myelography showed an intradural extramedullary cyst ((c) sagittal; (d) horizontal, arrow).
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fig4
Contrast-enhanced computed tomography of the spinal cord showed foraminal stenosis of the left C6-7 intervertebral foramen, along with an intradural extramedullary cyst (Figure 4).
Intraoperative findings. When the dura mater was incised at the C1-2 level, followed by incision in the denticulate ligaments on the right side of the spinal cord, a cystic lesion was present in the right C2 ventral root (arrowhead). The cyst (arrow), which caused compression and significant displacement of the cervical spinal cord from the right ventral side (a), was removed. The cyst capsule, however, seemed to remain in the ventral side and extend posterior to the odontoid process. We found that the dura mater was partly missing in the ventral side ((b) partially missing dura matter: arrowhead).
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fig5
The dura mater was coagulated and closed (Figure 5).
Histopathological findings. The hematoxylin and eosin staining showed synovial cells in the fibrocartilaginous capsule: (a) lower magnification; (b) higher magnification, bar: 100 mum.
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fig6
Pathological examination showed that slides contained both cyst contents and normal dura mater but tumor content (Figure 6).