PMC8492432_01
(a) Post-contrast axial computed tomography at the C5 level showing crushed paraspinal soft tissues around the right C4/5 intervertebral foramen with unclear delineation of the right vertebral artery (arrow). No extravasation of contrast agent is observed. (b) Non-contrast axial computed tomography of the head showing no abnormal findings in the lower cerebellum. Asterisk: Left vertebral artery.
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F2
The spinal CT at presentation revealed crushed paraspinal soft tissues around the right C4/5 intervertebral foramen with unclear delineation of the VA [Figure 2a]. Head CT performed at presentation did not show any abnormal findings in the lower cerebellum [Figure 2b].
Post contrast axial computed tomography at the C5 level (a) and its delayed-phase image (b) showing lateral protrusion of the right vertebral artery wall (arrow). (c) Three-dimensional computed tomography angiography, right posterolateral view, showing an aneurysm with a maximal dimension of 10 mm projecting laterally (arrow) at the C4/C5 level. Dominance between the vertebral arteries is not observed. CCA: common carotid artery, H: head side, P: posterior, R: right, SCA: subclavian artery, Asterisk: vertebral artery.
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F3
Spinal CT performed again on posthospitalization day 7 identified lateral protrusion of the right VA wall at the C4/5 level [Figure 3a and b]. Three-dimensional CT and catheter angiography showed a broad-based VA aneurysm with an irregular contour [Figures 3c and 4a] projecting laterally at the C4/5 level, with a maximal dimension of 10 mm.
Intraprocedural images. (a) Right vertebral arteriogram, oblique view, showing a broad-based aneurysm with an irregular contour (arrow). (b) Three-dimensional right vertebral angiogram, oblique view, showing abnormal shunts formed between the aneurysm (arrow) and paravertebral venous plexus (arrowheads). Oblique view of the right vertebral arteriogram (c) and lateral view of the cervical X-ray (d) showing obliteration of the vertebral artery segment involving the aneurysm (arrow). Asterisk: Vertebral artery.
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F4
Three-dimensional CT and catheter angiography showed a broad-based VA aneurysm with an irregular contour [Figures 3c and 4a] projecting laterally at the C4/5 level, with a maximal dimension of 10 mm. In addition, abnormal arteriovenous shunts were observed between the aneurysm and the paravertebral venous plexus [Figure 4b]. Then, the patient underwent emergency coil embolization of the VA segment involving the aneurysm on the same day [Figure 4c and d].
Cerebral magnetic resonance angiography (a) performd immediately after surgery showing the intact flow of the right vertebral artery, while not detecting the posterior inferior cerebellar artery. Axial diffusion-weighted magnetic resonance image (b and c) showing an infarct in the distribution area of the right posterior inferior cerebellar artery.
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F5
The right PICA was not detected on cerebral magnetic resonance angiography [Figure 5].