case_images: PMC9345094_01
case_images: Computed tomography (CT) scans on admission. (a and b) CT scan with bone window demonstrates a large lesion in the right frontoparietal cranium expanding into the diploic space and exerting a mass effect on the right frontal lobe. (c and d) Perfusion CT shows that cerebral blood flow (c) and cerebral blood volume (d) are increased in the right frontal mass. (e) The venous phase of four-dimensional CT angiography displays occluded superior sagittal sinus.
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case_images: F1
case_images: C4, F8, T4, and T6. Computed tomography (CT) scan showed a 10.7 x 10.0 x 5.5-cm mass from the right frontal to the parietal bone, expanding into the diploic space, and partly extending beyond the sagittal suture to the contralateral side [Figures 1a and b]. Perfusion CT-indicated increased blood flow and volume [Figures 1c and d]. Furthermore, the venous phase of four-dimensional CT angiography revealed that the superior sagittal sinus (SSS) was occluded due to the tumor [Figure 1e].
case_images: Magnetic resonance imaging (MRI) on admission. (a and b) Both T1- (a) and T2-weighted MRI (b) display high-intensity mass with flow void. The right frontal lobe is compressed by the mass, causing a midline shift. (c) T1-weighted fat-suppressed MRI with contrast shows a mass with heterogeneous enhancement. Fat suppression reveals low signal in most of the mass, suggesting the presence of adipose tissue in the mass. (d-f) T1-weighted fat-suppressed MRI with contrast displays large cranial tumor with superior sagittal sinus (SSS) obstruction.
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case_images: F2
case_images: T1WI, suggesting a tumor with a fat component [Figures 2a-f]. There was no signal change in the brain parenchyma, but it was accompanied by a midline shift [Figure 2b]. The right external carotid artery angiography revealed marked tumor staining from the right middle meningeal artery (MMA) [Figure 3a]. The tumor was fed mainly from the anterior branch of the MMA, and the other feeders were the posterior convexity branch of the MMA, deep temporal artery (DTA), and superficial temporal artery.
case_images: Cerebral angiogram on admission and after preoperative embolization. (a) The arterial phase of the right external carotid angiography shows a marked tumor staining from the right middle meningeal artery. Notably, dilated blood vessels are noted. (b) The venous phase of right external carotid angiography shows varices and congestion of contrast medium. (c) Right external carotid artery angiography after endovascular embolization confirms no residual hypervascular mass and arteriovenous shunt.
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case_images: F3
case_images: T1WI, suggesting a tumor with a fat component [Figures 2a-f]. There was no signal change in the brain parenchyma, but it was accompanied by a midline shift [Figure 2b]. The right external carotid artery angiography revealed marked tumor staining from the right middle meningeal artery (MMA) [Figure 3a]. The tumor was fed mainly from the anterior branch of the MMA, and the other feeders were the posterior convexity branch of the MMA, deep temporal artery (DTA), and superficial temporal artery. Furthermore, the draining veins were highly dilated within the tumor and formed varices [Figure 3b]. A couple of the drainers were also delineated in the arterial phase, suggesting the presence of an AVF [Figure 3a]. Finally, the tumor stain was dramatically reduced after embolization [Figure 3c].
case_images: Intraoperative photograph. The tumor is exposed on the right frontotemporal bone.
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case_images: F4
case_images: When the flap was inverted, the tumor was partially exposed on the bone [Figure 4].
case_images: Postoperative computed tomography (CT) scan. CT scans before (a and b) and after (c and d) placement of the titanium plate are provided. (a and b) A large craniotomy is shown. Compression on the brain is greatly improved. (c and d) The skull defect is reconstructed with a vast mesh plate, and there is no brain compression.
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case_images: F5
case_images: The bleeding was controlled by removing the inner table and attaching dura, but a small part of the tumor near the SSS was left behind to preserve venous return [Figures 5a and b]. Cranioplasty was performed using a custom-made titanium mesh plate 1 month after the tumor resection [Figures 5c and d].
case_images: MRI 2 years after the operation. (a-c) MRI 2 years after the surgery shows no tumor recurrence, and the occluded SSS is refluxed.
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case_images: F6
case_images: MRI performed 2 years after the surgery showed no tumor recurrence, the occluded SSS was refluxed, and the midline shift had disappeared [Figures 6a-c]. Taken together with the lack of cytological atypia of adipocytes and vessels [Figure 6b], there were no findings suggestive of malignancy; thus, the patient was finally diagnosed with angiolipoma.
case_images: Hematoxylin and eosin (H&E) staining of the specimens with different magnifications. (a) Loupe image shows that tumors comprising various-sized blood vessels and fat are enlarged under the cortical bone. (b) A high-power image displays that multiple blood vessels are interspersed in mature adipose tissue (H&E, original magnification, x20). (c) Pathology photograph of aneurysm-forming vessels is provided. The elastic plate and smooth muscle of the tunica media are not clear, consistent with varices. (H&E, original magnification, x2). (d) A high-power image reveals mild inflammatory cell infiltration in the outer membrane (H&E, original magnification, x10).
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case_images: F7
case_images: Histological examination revealed that the intracranial tumor was composed of mature adipocytes with various-sized dilated vessels [Figures 7a and b]. The abnormal vessels in the tumor had varices with a mild chronic inflammatory cell infiltration in the adventitia [Figures 7c and d].