PMC9610206_01
Preoperative magnetic resonance imaging (MRI) T1WI and T2WI sagittal view. T1-weighted magnetic resonance (MR) imaging demonstrated retro-odontoid pseudotumor with double-layer sign; T1 MR showed both layers with isointense areas (a) while T2 MR showed mixed intensity areas of a secondary dorsal layer (b).
SNI-13-446-g001.jpg
PMC9610206_01_SNI-13-446-g001.jpg
F1
T2 MR studies demonstrated ROP and the double-layer sign; T1 unenhanced MR studies showed that both layers were isointense areas while T2 MR showed a mixed intensity secondary dorsal layer [Figures 1a and b]. The patient's cervical myelopathic deficits resolved following a C1-C2 posterior decompression and fusion.
Postoperative MRI T1WI. The patient was treated by posterior fusion and both layers were regressed.
SNI-13-446-g002.jpg
PMC9610206_01_SNI-13-446-g002.jpg
F2
On follow-up MR studies, both layers regressed [Figure 2].