case_images: PMC10874249_01
case_images: Initial brain magnetic resonance imaging.. Contrast-enhanced T1-weighted images show an intraventricular mass in the third ventricle to the anterior horn of the left lateral ventricle (A-C; white arrow) with hydrocephalus. Corpus callosum agenesis is noted in the coronal and sagittal images (B and C; yellow arrows).
case_images: cureus-0016-00000052510-i01.jpg
case_images: PMC10874249_01_cureus-0016-00000052510-i01.jpg
case_images: FIG1
case_images: Initial treatment for suspected viral meningitis did not lead to improvement, and an initial MRI revealed an intraventricular mass measuring 52x22 mm and characterized as a heterogeneous enhancing tumor with cystic components, along with agenesis of the corpus callosum (Figures 1A-1C).
case_images: Preoperative CT and MRI one month after the initial visit.. (A) Axial computed tomography (CT), (B) T2-weighted image (T2WI), (C) T2*WI, (D) T1WI, (E)diffusion-weighted image (DWI), (F) apparent diffusion coefficient (ADC) map, (G) axial postcontrast T1WI, and (H) coronal postcontrast T1WI.. The tumor consisted of two following components: the ventral component appeared dense on CT, slightly hyperintense on T1WI, demonstrated contrast enhancement on postcontrast T1WI, and had a decreased ADC value (F; yellow arrow). The dorsal component showed ring enhancement on postcontrast T1WI and an increased ADC value in the solid component (E and F; white arrows). In DWI, both components showed signals close to the cerebral white matter, and no marked high signals were observed. No hemorrhage or calcification was observed on T2*WI (C). The tumor predominantly occupies the third ventricle and left Moro foramen, located beneath the thalamostriate vein (H; black arrow), and appears contiguous with the brain parenchyma (H; blue arrow).
case_images: cureus-0016-00000052510-i02.jpg
case_images: PMC10874249_01_cureus-0016-00000052510-i02.jpg
case_images: FIG2
case_images: Preoperative computed tomography (CT) and MRI performed one month later showed an enlarged tumor (Figures 2A-2H). The tumor consisted of two following components: the ventral component appeared dense on CT, slightly hyperintense on T1-weighted images (T1WI), demonstrated contrast enhancement on postcontrast T1WI, and had a decreased apparent diffusion coefficient (ADC) value (Figure 2, yellow arrows). The dorsal component showed ring enhancement on postcontrast T1WI, and an increased ADC value in the solid component (Figure 2, white arrows). T2*WI (Figure 2C). The tumor predominantly occupies the third ventricle and left Moro foramen, located beneath the thalamostriate vein (Figure 2H, black arrow), and appears contiguous with the brain parenchyma (Figure 2H, blue arrow). Therefore, an exophytically growing high-grade glioma, such as glioblastoma, was considered.
case_images: Intraoperative endoscopic images.. Intraoperative endoscopic images viewed from the frontal horn of the left ventricle showed a tumor (*) located beneath the brain parenchyma and near the left thalamostriate vein (A; white arrow). A gentle elevation, indicative of an intraaxial tumor, arises from the left frontal lobe (B; white arrows). The tumor nearly occludes the foramen of Monro. Resection of the tumor surface was performed using tumor forceps, with careful avoidance of the tumor's red area.
case_images: cureus-0016-00000052510-i03.jpg
case_images: PMC10874249_01_cureus-0016-00000052510-i03.jpg
case_images: FIG3
case_images: Postoperative MRI of the patient.. Contrast-enhanced T1-weighted images display a reduced tumor in the ventricles (A and B) and improved hydrocephalus, with the mass's decreased size more clearly indicating its left frontal basal origin (A and C; arrows).
case_images: cureus-0016-00000052510-i04.jpg
case_images: PMC10874249_01_cureus-0016-00000052510-i04.jpg
case_images: FIG4
case_images: Postoperative MRI showed a reduced intraventricular mass volume, clarifying that the mass protruded from the base of the left frontal lobe into the ventricles (Figures 4A-4C; arrows).
case_images: H&E stained histology images of the excised specimen.. The histological specimen displayed characteristics of pleomorphic xanthoastrocytoma. Most nuclei were enlarged and exhibited bizarre shapes, accompanied by a vacuous, foamy cytoplasm (A). A significant number of xanthic cells were observed (B); numerous eosinophilic granular bodies were also visible (C). Mitotic figures are present (D).
case_images: cureus-0016-00000052510-i05.jpg
case_images: PMC10874249_01_cureus-0016-00000052510-i05.jpg
case_images: FIG5
case_images: The histological specimen revealed characteristics consistent with PXA (Figures 5A-5D).