PMC5437802_01
(a) Coronal slice from the follow-up angio-magnetic resonance imaging showing the reconstitution of the physiological caliber of the right transverse-sigmoid sinus. Comparison between preoperative (b) and follow-up (c) axial magnetic resonance imaging images demonstrating the resolution of two important radiological signs of intracranial hypertension: the posterior flattening of the ocular globes and the papillary protrusion
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F1
The patient underwent a magnetic resonance imaging (MRI) scan of the brain with Gadolinium which showed signs in keeping with longstanding raised ICP, including bilateral kinking of the optic nerves within the orbit, enlargement of subarachnoid spaces, flattening of the posterior sclera, and the empty sella sign [Figure 1b].
(a) Angiographic sequence showing the mild right sinus dominance and the clear effect of the compression on the transverse-sigmoid junction. (b) Angio-magnetic resonance imaging coronal slice showing the hyperintense solid lesion responsible for the hampering of the venous blood flow
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F2
The same investigation documented a single, 16 mm, oval, T1 and T2 isointense, contrast-enhancing lesion arising in the right mastoid region, and narrowing the transverse-sigmoid sinus junction [Figure 2b]. A cerebral angiography digital subtraction angiography documented the compression of the right transverse-sigmoid junction distal to the vein of Labbe, within a picture of mild right side dominance of the venous sinuses circulation in the posterior fossa [Figure 2a].
Histological preparation of the lesion. It shows the typical structure of the osteoblastoma consisting in anastomosing bone trabeculae embedded in a loose fibro-vascular stroma (H and E, x200)
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F3
The histological examination was in keeping with a diagnosis of osteoblastoma [Figure 3].