PMC10069914_01
Computed tomography images.
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Head computed tomography (CT) revealing subarachnoid hemorrhage, primarily in the right prepontine cistern, and aneurysm-like structures in the interpeduncular cistern (a, b). The bilateral carotid canals are hypoplastic (right, 2.9 mm; left, 3.4 mm) (c), and the right nasal cavity is obstructed (d, white arrow). Bone CT revealing hypoplasia of the bilateral zygomatic bone and mandible (e, f).
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Head computed tomography (CT) revealed SAH, particularly in the right prepontine cistern, and aneurysm-like structures in the interpeduncular cistern (Fig. 1a, b). The diameters of the hypoplastic ICAs were 2.9 mm (right) and 3.4 mm (left) (Fig. 1c). The right external auditory meatus and nasal cavity were obstructed (Fig. 1d). CT showed bilateral zygomatic bone and mandible hypoplasia (Fig. 1e, f). CT angiography (CTA) revealed bilateral ICA hypoplasia (Fig. 2a, b).
Computed tomography angiography images.
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Computed tomography angiography (CTA) revealing bilateral internal carotid artery (ICA) hypoplasia above the cervical bifurcation (a, b). Aneurysmal changes at the basilar artery tip (black arrowhead), right ICA terminal segment (white arrowhead), and right anterior inferior cerebellar artery (AICA) origin (white arrow) can be seen on the CTA image (c).
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ECA, external carotid artery
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CT showed bilateral zygomatic bone and mandible hypoplasia (Fig. 1e, f). CT angiography (CTA) revealed bilateral ICA hypoplasia (Fig. 2a, b). Aneurysmal changes in the basilar artery tip, right ICA terminal segment, and right anterior inferior cerebellar artery (AICA) origin were also detected on CTA (Fig. 2c).
Vertebral angiograms.
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Right vertebral angiograms revealing aneurysmal changes at the basilar artery tip (black arrowhead) and right anterior inferior cerebellar artery (AICA) origin (white arrow) (a, b).
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Eight coils were used to embolize the right AICA aneurysm (c: preoperative; d: postoperative).
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Tactics (Technocrat Corporation, Aichi, Japan)/Excelsior SL-10 Microcatheter (Stryker Neurovascular, Fremont, USA)/0.014 Transend EX SOFT TIP guidewire (Endeavor; Boston Scientific/Target, Fremont, CA) was coaxially guided into the aneurysm, and eight coils were used for embolization. The surgery was completed once we confirmed the absence of blood flow through the aneurysm and an intact AICA (Fig. 3a-d).