2023 Volume 51 Issue 3 Pages 222-226
Background: Internal coil trapping of the vertebral artery (VA), including aneurysms, is one of the first-line treatments for ruptured intracranial vertebral artery dissecting aneurysm (VADA). However, brainstem infarction is a major complication of this procedure. Herein, we report brainstem infarction associated with internal coil trapping of the VADA and related risk factors.
Methods: Between January 2003 and April 2020, 61 patients were treated for VADA. The exclusion criteria were as follows: patients who did not undergo internal coil trapping, patients with a dissection extending to the basilar artery, and/or patients who did not undergo magnetic resonance imaging on the day after treatment.
Results: Fifty-two eligible patients that met the inclusion criteria were enrolled in the study. Brainstem infarction occurred in 13 of the 52 patients (25%). The length of the internal coil trapping was strongly correlated with the length of the VADA (correlation coefficient = 0.945, p＜0.001). Factors significantly associated with the occurrence of brainstem infarction were a history of hyperlipidemia (p = 0.016), non-posterior inferior cerebellar artery (PICA)-type VA (p = 0.001), longer VADA(p = 0.003), and longer internal coil trapping (p = 0.006). Ten of the thirteen patients with brainstem infarction and 12 of the 39 patients without brainstem infarction resulted in a modified Rankin Scale score ≥2 at discharge. The outcomes of the patients with brainstem infarction were significantly worse than those without brainstem infarction (p = 0.004).
Conclusion: Brainstem infarction, which results in worse outcomes, is a major problem associated with internal coil trapping in ruptured VADA. To prevent brainstem infarction, preoperative angiographic evaluations, including that of the PICA, and the relationship between the PICA and aneurysm, might be important. Furthermore, the dense packing of coils in the VA as short as possible should be paid attention to during the embolization. Therefore, this study suggests that even if short and dense embolization is performed during internal coil trapping, brainstem infarction cannot always be prevented due to the anatomical conditions of the VADA.
