PMC10400907_01
(A-C) Preoperative head CT revealed early ischemic changes in the right parahippocampal gyrus (arrowhead) without intracranial hemorrhage and showed the hyperdense vessel sign in the BA and the left posterior cerebral artery (arrows). (D and E) Preoperative left subclavian artery angiography showed no evidence of the left VA. (F) Right subclavian artery angiography revealed the hypoplastic right VA (arrow). BA: basilar artery; VA: vertebral artery
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Head CT revealed a low-density lesion in the right parahippocampal gyrus without intracranial hemorrhage or obvious early ischemic changes in the brainstem. Head CT also showed a hyperdense vessel sign in the BA, due to a thrombus approximately 30 mm in length from the mid BA to the P1 segment of the left posterior cerebral artery (Fig. 1A-1C). Flexor Shuttle guiding sheath 80 cm (Cook Medical, Bloomington, IN, USA) into the dominant left VA via the right femoral artery under local anesthesia. For this, we first performed left subclavian artery angiography, which showed no evidence of a left VA (Fig. 1D and 1E). Next, we performed right subclavian artery angiography, which showed a hypoplastic right VA that was too small to allow navigation of a large bore aspiration catheter (Fig. 1F).
Preoperative DSA of the left CCA. (A) AP view and (B) lateral view: showed the type 1 persistent PPA originating from the left ECA at the level of the C2 vertebral body that coursed between the C1 arch and occipital bone (arrows). Preoperative DSA of the PPA. (C) AP view and (D) lateral view: the BA was occluded just distal to the AICA (arrows). AICA: anterior inferior cerebellar artery; AP: anteroposterior; BA: basilar artery; CCA: common carotid artery; ECA: external carotid artery; PPA: proatlantal artery
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Finally, the catheter was navigated into the left CCA and angiography was performed, which showed the origin of the left VA from the PPA, which itself originated from the left ECA at the level of the C2 vertebral body (Fig. 2A and 2B).
(A and B) Digital angiogram during the procedure (A: AP view and B: lateral view): the Penumbra 5MAX ACE 60 catheter was navigated into the occluded BA (arrow). (C) A red thrombus 28 mm in length was retrieved by MT. (D and E) DSA of the left ECA immediately after the first attempt (D: AP view and E: lateral view): recanalization of the BA was achieved successfully, although with distal occlusion of the posterior cerebral arteries bilaterally. (F) MRA performed the day after thrombectomy showed good recanalization of the BA and absence of bilateral PCoAs. (G and H) MRI FLAIR images on the day after thrombectomy revealed a large hemorrhagic infarction in the pons (ECASS criteria: PH2) and infarction in the right temporal and bilateral occipital lobes. AP: anteroposterior; BA: basilar artery; ECA: external carotid artery; ECASS: European Cooperative Acute Stroke Study; MT: mechanical thrombectomy; PCoAs: posterior communicating arteries
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Alameda, CA, USA) aspiration catheter was navigated to the occlusion site with a coaxial system using a Velocity microcatheter (Penumbra Inc.) and Asahi Chikai micro guidewire (Asahi Chikai, Asahi Intecc, Aichi, Japan) (Fig. 3A and 3B). After the 5MAX ACE aspiration catheter contacted the clot, aspiration was commenced with a MAX pump (Penumbra Inc.) for 120 sec, and the aspiration catheter was withdrawn into the guiding sheath. A large red thrombus with a total length of 28 mm was retrieved (Fig. 3C) and successful recanalization of the BA was achieved at the first thrombectomy attempt, although with the subsequent development of distal occlusion of the branches of the posterior cerebral arteries (PCAs) bilaterally (Thrombolysis in Cerebral Infarction scale 2b) (Fig. 3D and 3E). Cooperative Acute Stroke Study [ECASS] criteria: PH2) and infarction in the right temporal and bilateral occipital lobes (Fig. 3G and 3H). Cervical MRA showed that the left PPA originated from the ECA at the level of the C2 vertebral body (Fig. 4A), ascended to the suboccipital space without passing through the transverse foramen of the atlas (Fig. 4B) and coursed between the atlas and occipital bone to enter the foramen magnum (Fig. 4C).
Cervical MRA source image on the day after thrombectomy. (A) At the level of the C2 vertebral body: the left PPA (arrow) originated from the left ECA (arrowhead). (B) At the level of the C1 vertebral body: unlike the contralateral VA (arrowhead), the left PPA (arrow) ascended without passing through the transverse foramen of the atlas. (C) At the level of the foramen magnum: the PPA (arrow) coursed between the C1 arch and occipital bone to enter the foramen magnum (arrowhead). ECA: external carotid artery; PPA: proatlantal artery; VA: vertebral artery
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Cooperative Acute Stroke Study [ECASS] criteria: PH2) and infarction in the right temporal and bilateral occipital lobes (Fig. 3G and 3H). Cervical MRA showed that the left PPA originated from the ECA at the level of the C2 vertebral body (Fig. 4A), ascended to the suboccipital space without passing through the transverse foramen of the atlas (Fig. 4B) and coursed between the atlas and occipital bone to enter the foramen magnum (Fig. 4C).