PMC6024507_01
Axial T2-weighted (a) and Sagital T2-weighted (b) images revealing central C4-C5 disc extrusion with effacement of the anterior subarachnoid space and compression / indentation of the spinal cord (hawk beak sign or Y sign, suggestive of intradural disc herniation - arrow)
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F1
The cervical spine magnetic resonance imaging (MRI) showed a large ossified/calcified central disc herniation at the C4/5 level with OPLL contributing to marked ventral cord compression [Figure 1].
(a) En bloc removal of the calcified disc fragment, protruding through the posterior longitudinal ligament and through the dura. (b) Central defect in the dura is observed, with arachnoid exposed. No CSF leak. Cord seen nicely pulsating through the arachnoid
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F2
ACDF was performed, they encountered a large calcified disc fragment with OPLL that was removed en bloc. Although there was a tear in the dura, the arachnoid remained intact; there was no accompanying cerebrospinal fluid (CSF) fistula [Figure 2].
Axial T2-weighted (a) and Sagital T2-weighted (b) images revealing status post-anterior discectomy and fusion (asterix) with repermeabilization of the anterior subarachnoid space and decompression of the spinal cord (punctate left paramedian spinal cord lesion is seen - arrow)
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F3
Notably, the postoperative MRI scan revealed adequate spinal cord decompression, but a punctate intramedullary C4-C5 cord contusion [Figure 3].