PMC9479517_01
(a) Preoperative axial computed tomography (CT) demonstrating ventriculomegaly. (b) Postoperative Axial CT demonstrating decrease in ventricle size following endoscopic third ventriculostomy. Pneumocephalus is evident on scan.
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F1
Findings were consistent with chronic hydrocephalus [Figure 1]. Postoperative head CT demonstrated a significant decrease in hydrocephalus [Figure 1b].
Axial T2 sequence magnetic resonance imaging (MRI) illustrating cortical subarachnoid hemorrhage (SAH)/siderosis from chronic SAH.
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F2
Magnetic resonance imaging (MRI) of the brain demonstrated chronic cortical SAH (cSAH)/superficial siderosis of the parasagittal frontoparietal sulci and left anterior frontal sulci [Figure 2].
Arrows point to multifocal stenosis of medium to small caliper cerebral arteries demonstrated on angiography. (a) Red arrow: R. posterior cerebral artery; White arrow: R. superior cerebellar artery; Orange arrow: R. anterior inferior cerebellar artery; Black arrow: L. superior cerebellar. (b) Yellow arrow: R. anterior cerebral artery; Red arrow: R. posterior cerebral artery. (c) Blue arrows: L. middle cerebral artery.
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F3
CT angiogram. Cerebral angiography confirmed these results [Figures 3a-c].
MRI/cerebrospinal fluid: cerebrospinal fluid flow study. Red arrow: arachnoid cyst membrane; Orange arrow: splayed optic tracks; Blue arrow: flattened infundibular recess; Yellow arrow: stenotic cerebral aqueduct.
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F4
CSF flow study was subsequently performed, revealing partial obstruction of the cerebral aqueduct [Figure 4]. CSF obstruction was found at the junction of the cerebral aqueduct and the superior aspect of the fourth ventricle.
Intraventricular arachnoid cyst: Endoscopic third ventriculostomy screenshot.
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F5
Intraoperative endoscopy located a large cyst within the third ventricle obscuring the ventricular floor [Figure 5].