Dissecting Vertebral Artery Aneurysm Presenting Regrowth After Stent-Assisted Coil Embolization in Acute Stage

Delineability and anatomical variations of perforating arteries from normal vertebral artery on 3D DSA: implications for endovascular treatment of dissecting aneurysms

BACKGROUND AND PURPOSE

Endovascular trapping of the vertebral artery dissecting aneurysms (VADAs) carries a risk of medullary infarction due to the occlusion of the perforating arteries. We evaluated the detectability and anatomical variations of perforating arteries arising from the vertebral artery (VA) using three-dimensional DSA.

METHODS

In 120 patients without VA lesions who underwent rotational vertebral arteriography, the anatomical configurations of perforating arteries from the VA were retrospectively evaluated on the bi-plane DSA and reconstructed images to reach the consensus between two experienced reviewers. The images were interpreted by focusing on the numbers and types of perforating arteries, the relationships between the number of perforators and the anatomy of the VA and its branches.

RESULTS

Zero, 1, 2, 3, 4, and 6 perforators were detected in 2, 51, 56, 9, 1, and 1 patient, respectively (median of 2 perforators per VA). The 200 perforators were classified into 146 terminal and 54 longitudinal course types and into 32 ventral, 151 lateral, and 17 dorsolateral distribution types. All ventral type perforators were also terminal type. In contrast, the longitudinal type was seen in 28.5% of lateral types and in 65% of dorsolateral types. Regarding the difference in the origin of the posterior inferior cerebellar artery (PICA), non-PICA type VAs gave off larger number of perforators than the other types of VAs.

CONCLUSIONS

Non-PICA type VAs give off a significantly larger number of perforators than other types, indicating that the trapping of non-PICA type VAs is associated with a risk of ischemic complications.

Comparison of Clinical and Radiologic Outcomes of Diverse Endovascular Treatments in Vertebral Artery Dissecting Aneurysm Involving the Origin of PICA

OBJECTIVE

To determine clinical and radiologic outcomes of vertebral artery dissecting aneurysms involving posterior inferior cerebellar artery according to different types of endovascular treatment.

METHODS

This study included 18 vertebral artery dissecting aneurysms (6 ruptured and 12 unruptured) involving posterior inferior cerebellar artery treated from January 2009 to December 2016. Treatments were multiple stenting, stent-assisted coil embolization, vertebral artery trapping with vertebral artery-posterior inferior cerebellar artery stenting, and Pipeline embolization. Clinical and radiologic information were obtained from retrospective chart review and radiologic review.

RESULTS

Subarachnoid hemorrhage was diagnosed initially in 6 of 18 patients, and infarction was diagnosed initially in 2 patients. Multiple stenting was performed in 4 patients, including 1 (25%) who had cerebellar infarction and 1 (25%) who had recurrence. Stent-assisted coil embolization was performed in 8 patients, including 1 (12.5%) who had postoperative cerebellar infarction and 2 (25%) who had recurrence. Vertebral artery trapping with vertebral artery-posterior inferior cerebellar artery stenting was performed in 4 patients, including 1 (25%) who had postoperative cerebellar infarction. There was no recurrence (0%). Pipeline embolization was performed in 2 patients, including 1 (50%) who had recurrence. There was no postoperative infarction (0%). No subarachnoid hemorrhage occurred during follow-up. Deterioration in modified Rankin Scale score was found only in the stent-assisted coil embolization group (1/8; 12.5%).

CONCLUSIONS

Vertebral artery trapping with vertebral artery-posterior inferior cerebellar artery stenting showed the lowest rate of aneurysm recurrence with high rate of minor infarction and favorable neurologic outcome. Stent-assisted coil embolization showed high recurrence rates with possible fatal disabling infarction.