case_images: PMC10435885_01
case_images: Parasagittal T2w (A), T1w (B), and T1w post-contrast (C) images from L4 to S1 vertebrae revealing multiple well-defined, round-to-ovoid intradural-extramedullary space-occupying lesions (red arrows) at the level of L4-L5 intervertebral disk space and at the level of the lumbosacral junction. Compared with spinal cord parenchyma, the lesions were heterogeneously markedly hyperintense in T2w, iso- to hypointense in T1w images. After contrast-medium administration, the lesions were markedly contrast-enhancing. The lesions were causing marked-to-severe spinal cord and cauda equina spinal nerve compression. Parasagittal T2w (D), T1w (E), and T1w post-contrast (F) images at the level of the C7 vertebra revealed a single well-defined, heterogenous, round-to-ovoid intradural-extramedullary space-occupying lesion (red arrows). Compared to spinal cord parenchyma, the lesion was heterogeneously markedly hyperintense in T2w, iso- to hypointense in T1w images. After contrast-medium administration, the lesion was markedly contrast-enhancing. The lesion is causing marked-to-severe spinal cord compression Transverse T2w (G), T1w (H), and T1w post-contrast (I) images at the level of L4-L5 intervertebral disk space revealing a left-sided intradural-extramedullary space-occupying lesion (red arrows) causing severe spinal cord compression. Compared to spinal cord parenchyma, the lesions were heterogeneously markedly hyperintense in T2w, iso- to hypointense in T1w images. After contrast-medium administration, the lesions were markedly contrast-enhancing.
case_images: fvets-10-1223729-g0001.jpg
case_images: PMC10435885_01_fvets-10-1223729-g0001.jpg
case_images: F1
case_images: T1w images. The lesions were causing marked-to-severe spinal cord and cauda equina spinal nerve compression. The lesions were consistent with intradural-extramedullary neoplasia (Figure 1). Pre-contrast MRI from the C1 vertebra to T3 vertebrae revealed a similar intradural-extramedullary space-occupying lesion at the level of the C7 vertebra, measuring 1.2 cm in diameter (Figure 1). All the above lesions described were markedly homogenously contrast-enhancing (Figures 1, 2).
case_images: Midsagittal T2w (A), transverse T2w (B), transverse T1w (C), and transverse T1w post-contrast (D) images at the level of the lateral apertures revealing bilateral asymmetrical well-defined, heterogenous, intraventricular space-occupying lesions affecting the left side of the fourth ventricle and the left lateral aperture (red arrows) and the right side of the fourth ventricle and right lateral aperture (dotted red arrow). Compared with gray matter, the lesions were heterogeneously hyperintense in T2w images, iso- to hypointense in T1w images. After contrast-medium administration, the lesions were markedly contrast-enhancing. The lesions were causing moderate cerebellar and medulla oblongata compression.
case_images: fvets-10-1223729-g0002.jpg
case_images: PMC10435885_01_fvets-10-1223729-g0002.jpg
case_images: F2
case_images: A similar but smaller lesion could be observed in the caudal right aspect of the fourth ventricle, extending into the right lateral aperture (Figure 2). All the above lesions described were markedly homogenously contrast-enhancing (Figures 1, 2).
case_images: Macroscopic examination of a transverse fixed specimen of the patient's brain at the level of the lateral apertures (A) revealing a left-sided slightly irregular, soft, gray mass of maximum 1 cm in diameter (dotted red circle). The mass was compressing the adjacent medulla oblongata. Macroscopic examination of serial transverse fixed spinal cord segments at the level of C7 vertebra craniocaudally orientated (B) revealing a large, soft, gray, subdural mass present at the right ventral aspect of the spinal cord and expanding to displace almost the entire cord at its maximal limit (dotted red circles). There was severe spinal cord compression to approximately one-third of its original size.
case_images: fvets-10-1223729-g0003.jpg
case_images: PMC10435885_01_fvets-10-1223729-g0003.jpg
case_images: F3
case_images: This lesion compressed the medulla oblongata at the level of the left lateral aperture (Figure 3). The mass was displacing the leptomeninges rather than invading them (Figure 3).
case_images: (A) Overview of medulla oblongata showing bilateral well-demarcated neoplastic masses, most prominent on the left, causing a midline deviation to the right, HE stain, scale bar 5 mm; (B) overview of the cervical intumescence and mass, enclosed by the dura mater, with severe dorsal compression of the entire spinal cord, HE stain, scale bar 2.5 mm; (C) overview of the lumbar spinal cord and mass, with dorsal compression of the spinal cord. A neoplastic aggregate is also visible at the center of the spinal cord, within the spinal canal, HE stain, scale bar 2.5 mm; (D) high-power view of the primary neoplasm showing single layer papillary formations (cell dehiscence present owing to autolysis), monomorphic nuclei, and no mitoses present in this field, representative of cell morphology observed, HE stain, scale bar 100 mum, equivalent to x400.
case_images: fvets-10-1223729-g0004.jpg
case_images: PMC10435885_01_fvets-10-1223729-g0004.jpg
case_images: F4
case_images: A much smaller similar mass was found, affecting the right side of the medulla oblongata (Figure 4). The dura mater exhibited focal osseous metaplasia (Figure 4).