case_images: PMC8632699_01
case_images: Preoperative (A-F) and postoperative (G-I) MRI. A hypointense mass (white arrows) from the left orbit apex to the anterior cranial fossa is shown on T1-weighted axial (A) MRI scan. It is hyperintense on T2-weighted axial (B) and sagittal (C) MRI scans, with a significant enhancement on contrast images (D). Obvious hyperintensity is identified on the ADC map (E) but not on DWI (F). The mass is absent on both T1WI (G) and T2WI (H) while edema (red arrows) recedes incompletely. The contrast scan (I) shows no enhancement indicating the mass was excised completely.
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case_images: PMC8632699_01_fonc-11-763696-g001.jpg
case_images: f1
case_images: MRI revealed a mass occupying from the left orbit apex to the anterior cranial fossa, with hypointensity on T1-weighted images and hyperintensity on T2-weighted images ( Figures 1A-C ). Apparent and homogenous enhancement of the mass was observed on the gadolinium-enhanced MRI scans ( Figure 1D ), while the surrounding area showed no enhancement. The mass showed evident hyperintensity compared to brain parenchyma on ADC maps ( Figure 1E ) but not on DWI ( Figure 1F ). The surrounding area along the left optic nerve was hyperintense on DWI ( Figure 1G ), and was considered severe peritumoral edema. Postoperative MRI ( Figures 1H, I  ) showed a complete excision of the mass.
case_images: Hematoxylin-eosin staining of the excised mass (x20) (A) shows numerous capillary vessels containing red blood cells (black arrows) distributed in the vacuolated stromal cells (red arrows). Immunohistochemistry staining of the mass shows that the endothelial cells of capillary vessels (red arrows) were positive (brown=positive) for CD31 (B), CD34 (C), and F8-R (D). Some interspersed monocytes (red arrows) and macrophages (black arrow) were positive for CD68 (E). Vacuolated stromal cells are positive for GFAP (F) and NSE (G). CgA (H) and Syn (I) is negative among the whole sample tissue.
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case_images: PMC8632699_01_fonc-11-763696-g002.jpg
case_images: f2
case_images: CD68(+) monocytes and macrophages were also observed. CgA and Syn were both negative among the whole tissue ( Figure 2 ).