Small Unruptured Intracranial Aneurysms Can Be Effectively Treated With Flow-Diverting Devices

Transcirculation Approaches to Endovascular Flow Diversion of Intracranial Aneurysms: A Systematic Review With Technical Considerations

BACKGROUND AND OBJECTIVES

Flow diversion (FD) of intracranial aneurysms (IAs) is an increasingly used and efficacious treatment modality. Transcirculation approaches, or approaches that cross the contralateral or anteroposterior arterial supply before reaching a target vessel, have been used to treat cerebrovascular pathologies when traditional approaches are unsuitable or require intraoperative complication management. This study sought to review IAs treated with FD using a transcirculation approach to determine the technique's safety and efficacy.

METHODS

A systematic review of the PubMed, Scopus, Web of Science, and Embase databases was completed per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies were included if they described transcirculation approaches in adult patients with IAs undergoing FD. Outcomes of interest included intraoperative complications and aneurysm occlusion rates.

RESULTS

Twelve studies with 19 patients (N = 19, mean age = 54.1 y, 89.5% female) were identified. Wide-necked (N = 5, 26.3%) and saccular (N = 5, 26.3%) aneurysms were most represented, while 57.9% (N = 11) of aneurysms were unruptured and 15.8% (N = 3) of aneurysms were ruptured. The mean aneurysm sac and neck size were 16.9 mm and 11.9 mm, respectively. The most commonly deployed flow diverter was the Pipeline Embolization Device (N = 14, 73.9%). Successful FD (complete occlusion and/or good wall apposition) was recorded in 84.6% of qualifying patients with follow-up data, while 2 patients (15.4%) developed an intraoperative carotid-cavernous fistula.

CONCLUSION

Transcirculation approaches to FD offer neurointerventionalists a safe and efficacious method for device deployment, rescue scenarios, and challenging anatomy. Prospective studies may determine the most appropriate indications for transcirculation approaches to FD, while novel, lower profile devices may improve its technical feasibility and safety.

Pipeline Flex with Shield Technology Placement for Small- and Medium-sized Aneurysms Achieves Early Complete Occlusion

The flow diverter has been shown to be a safe and effective device for large cerebral aneurysms in the proximal internal carotid artery (ICA). Recently, its indication has been expanded to small- and medium-sized cerebral aneurysms in the distal segment of the ICA. In this study, we report a single-center, retrospective investigation of the safety and efficacy of the Pipeline Flex device to treat these aneurysms. Of the patients who underwent Pipeline implantation for small- and medium-sized ICA aneurysms (≤12 mm) at our hospital between July 2013 and October 2021, 102 patients with 104 aneurysms were included in this study. The mean age of the patients was 57.7 ± 12.1 years, and 94 (90.4%) were female. The mean aneurysmal dome diameter was 9.2 ± 2.3 mm, the mean neck diameter was 5.3 ± 1.6 mm, and the mean dome-to-neck ratio was 1.8 ± 0.5. Twenty-five patients (24.0%) had incorporated vessels from the aneurysm. Complete occlusion of the aneurysms was obtained in 96 patients (92.3%). There were no cases of parent artery stenosis or major stroke after the procedure. Absence of incorporated vessel from the aneurysm dome and adjunctive coil embolization are statistically significant factors indicating complete occlusion in multivariate analysis. The time to complete occlusion was determined earlier with the use of the Pipeline Shield (p = 0.0386) and with adjunctive coils (p = 0.0025). We showed that Pipeline implantation for small- and medium-sized aneurysms was safe and highly effective.

Risk factors for repeated recurrence of cerebral aneurysms treated with endovascular embolization

Purpose

To explore the risk factors of recurrence after second endovascular embolization of recurrent aneurysms and the characteristics of recurrent refractory aneurysms to help clinical decision-making.

Materials and methods

Forty-nine patients with recurrent aneurysms who underwent repeated embolization were retrospectively enrolled and divided into the recurrent and non-recurrent group. The risk factors of recurrence, complications and follow-up results of repeated embolization, and characteristics of recurrent refractory aneurysms were analyzed.

Results

Among the 49 patients with the second embolization, 5 were lost to follow-up, 9 recurred, and 35 did not. Univariate analysis showed that aneurysm size (P = 0.022), aneurysm classification (P = 0.014), and Raymond-Roy grade after the second embolization (P = 0.001) were statistically different between the two groups. Multivariate analysis demonstrated the Raymond-Roy grade as an independent risk factor for the recurrence of aneurysms after the second embolization (P = 0.042). The complication rate after the second embolization was 4%. There were five recurrent refractory aneurysms with an average aneurysm size of 23.17 ± 10.45 mm, including three giant aneurysms and two large aneurysms. To achieve complete or near-complete embolization of the recurrent refractory aneurysms, multiple treatment approaches were needed with multiple stents or flow diverting devices.

Conclusion

Aneurysm occlusion status after the second embolization is an independent risk factor for the recurrence of intracranial aneurysms. Compared with near-complete occlusion, complete occlusion can significantly reduce the risk of recurrence after second embolization. In order to achieve complete or near-complete occlusion, recurrent refractory aneurysms need multiple treatments with the use of multiple stents or flow diverting devices.