case_images: PMC9902057_01
case_images: Preoperative MRI (T2 sagittal) showing a well-defined extradural and ventrodorsal lesion causing severe impingement of the spinal cord (arrow).
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case_images: PMC9902057_01_cureus-0015-00000033496-i01.jpg
case_images: FIG1
case_images: The magnetic resonance imaging (MRI) revealed a well-defined extradural, intensely enhancing right-sided ventrodorsal semicircular lesion causing severe spinal cord impingement (Figure 1) as well as a periaortic soft tissue mass (Figure 2).
case_images: Preoperative MRI (T2 axial) showing a dilated thoracic aorta with a periaortic soft tissue mass (arrow).
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case_images: PMC9902057_01_cureus-0015-00000033496-i02.jpg
case_images: FIG2
case_images: The magnetic resonance imaging (MRI) revealed a well-defined extradural, intensely enhancing right-sided ventrodorsal semicircular lesion causing severe spinal cord impingement (Figure 1) as well as a periaortic soft tissue mass (Figure 2).
case_images: Preoperative CT-aortogram (3D) showing a dilated aorta with a periaortic mass lesion (arrow).
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case_images: FIG3
case_images: The CT aortogram revealed diffuse thickening and enhancement of the ascending aorta, aortic arch, and descending aorta, with periaortic mass measuring up to 13 mm (Figure 3).
case_images: Hematoxylin-eosin stain (x400) of the tissue specimen from the dural mass lesion showing a dense chronic inflammatory infiltrate composed of foamy histocytes, lymphocytes, and plasma cells.
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case_images: FIG4
case_images: Histopathological examination of the tissue revealed a dense chronic inflammatory infiltrate composed of foamy histocytes, lymphocytes, and plasma cells (Figure 4).
case_images: Postoperative MRI (T2 sagittal) showing near-complete resolution of the extradural mass lesion (arrow).
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case_images: FIG5
case_images: TA, the rheumatologist prescribed oral prednisolone 20 mg/day and mycophenolate mofetil 1500 mg/day. The immunotherapy was gradually tapered over six months, and a six-month follow-up MRI revealed a near-complete reduction in the extradural mass (Figure 5) as well as full neurological recovery (Power 5/5).