Figure 4. Postoperative MRI and PET-CT scans of an 82-year-old man following tumor debulking. (A) Sagittal and (B) axial T1-weighted (W) MR images performed following posterior laminectomy and tumor debulking show residual tumor predominantly in the anterior epidural space at C7 level (red arrows). Note the post-laminectomy changes on the sagittal T1W post-contrast image (white arrows). (C) Axial positron emission tomographic-computed tomography (PET-CT) image at C7 level shows focal increased 18F-FDG uptake at the anteromedial aspect of the C7 vertebral region, with maximum standardized uptake values, SUVmax=25, indicating residual tumor (red arrow, C) while the mild focal uptake at the right paraspinal soft tissue (SUVmax=8) represents a post-treatment effect (white arrow, C). (D) Axial PET-CT image at L1 level shows a faint focal uptake in the posterior aspect of the conus medullaris (SUVmax=3.5), which was indeterminate at the time of scanning, but subsequent follow-up showed it to be a drop metastasis.