case_images: PMC10741809_01
case_images: (A) Coronal computed tomography (CT) angiography of the head demonstrates short segment occlusion of the right supraclinoid segment of the internal carotid artery (arrow). (B) Axial view shows collateral flow from contralateral anterior circulation across the anterior communicating artery (arrow). (C) The bilateral middle cerebral arteries fill completely on axial CT angiography without branch occlusions (arrows), as does (D) the right posterior cerebral artery through the anterior communicating artery (arrow).
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case_images: PMC10741809_01_toj-23-0042-figure1.jpg
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case_images: Computed tomography (CT) angiography demonstrated total occlusion of the right supraclinoid segment of the internal carotid artery (Figure 1). Distal to the occlusion, complete filling of the anterior cerebral artery and middle cerebral artery territories suggested significant collateralization, speculatively via the anterior communicating artery complex (Figure 1).
case_images: Computed tomography perfusion scan of the brain shows (A) increased mean transit times (MTT) in right middle cerebral artery territory and (B) normal symmetric cerebral blood volumes (CBV), indicative of a large penumbra.
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case_images: CT perfusion demonstrated a large right hemispheric penumbra with preserved blood volume (Figure 2).
case_images: Lateral digital subtraction angiography (DSA) of the right internal carotid artery shows (A) chronic occlusion of the communicating segment of the right internal carotid artery (arrow) and retrograde flash filling of the basilar artery (double arrows) via the posterior communicating artery. (B) Mid-arterial phase shows leptomeningeal collateral flow from the splenial branch of the posterior cerebral artery (arrow) to the pericallosal branch of the anterior cerebral artery (double arrows) that fills retrograde, as well as leptomeningeal collateralization (C) between the middle cerebral artery (arrow) and proximal anterior cerebral artery (double arrows). (D) Anteroposterior DSA right internal carotid artery injection shows dominance of the internal carotid artery in perfusing the vertebrobasilar system (double arrowheads) via retrograde flow of the right posterior cerebral artery P1 segment (arrow).
case_images: toj-23-0042-figure3.jpg
case_images: PMC10741809_01_toj-23-0042-figure3.jpg
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case_images: The late arterial phase showed right ipsilateral leptomeningeal collateralization from the posterior cerebral artery to the anterior cerebral artery and middle cerebral artery posterior division (Figure 3).
case_images: Anteroposterior digital subtraction angiography of the left internal carotid artery demonstrates (A) acute occlusion of the left A1-A2 junction (arrow). (B) Postthrombectomy injection demonstrates recanalization of left A1-A2 junction, bilateral anterior cerebral arteries, and bilateral middle cerebral arteries (arrows).
case_images: toj-23-0042-figure4.jpg
case_images: PMC10741809_01_toj-23-0042-figure4.jpg
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case_images: Given the patient's acute neurologic deterioration, the left internal carotid artery was selected to confirm etiology, demonstrating large vessel occlusion of the left A1-A2 junction by acute thrombus that was not clearly seen on CT angiography (Figure 4). Postthrombectomy injection confirmed total recanalization, thrombolysis in cerebral infarction score of 3, and patency of the bilateral middle cerebral artery and bilateral anterior cerebral artery territories (Figure 4).