case_images: PMC9969324_01
case_images: Axial computed tomography of the head demonstrating extensive diffuse subarachnoid hemorrhage involving the premedullary and prepontine cisterns extending into the basal cisterns (A) and evidence of early obstructive hydrocephalus (B)
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case_images: FIG1
case_images: Non-contrast computed tomography (CT) of the head revealed diffuse SAH and associated ventriculomegaly (Figure 1).
case_images: Computed tomography angiography of the head (mean intensity projection) without evidence of basilar perforator aneurysm in the sagittal (A) nor the coronal (B) plane
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case_images: FIG2
case_images: Initial CT angiography (CTA) as well as cerebral digital subtraction angiography (DSA) did not reveal an aneurysm or other vascular lesion (Figure 2).
case_images: Three-dimensional reconstructions from digital subtraction angiography post-bleed day 1 demonstrating angiographic occult perforator aneurysm arising from the distal basilar artery near its junction with the right superior cerebellar artery (A) and a similar angled reconstruction created during digital subtraction angiography following re-rupture (B) as well as lateral view of the aneurysm (C)
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case_images: FIG3
case_images: He was taken to the angiography suite where a small non-trunk basilar perforator aneurysm was identified (Figure 3).
case_images: Operative approach to a ruptured distal basilar perforating artery aneurysm
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case_images: VID1
case_images: Magnetic resonance imaging was obtained after surgery, which demonstrated a small area of diffusion-weighted restriction in the right anterior portion of the rostral pons, suggestive of infarct from occluding the perforator (Figure 4A). Postoperative cerebral DSA confirmed obliteration of aneurysm from circulation (Figure 4B).