Open Microsurgical Cerebral Aneurysm Treatment After Failed Endovascular Therapy: An Evaluation of Aneurysm Treatment Frequencies in All Neurovascular Centers Across Austria and the Czech Republic Over 20 Years.

BACKGROUND AND OBJECTIVES: Endovascular treatment of cerebral aneurysms has tremendously advanced over the past decades. Nevertheless, aneurysm residual and recurrence remain challenges after embolization. The objective of this study was to elucidate the portion of embolized aneurysms requiring open surgery and evaluate whether newer endovascular treatments have changed the need for open surgery after failed embolization. METHODS: All 15 cerebrovascular centers in Austria and the Czech Republic provided overall aneurysm treatment frequency data and retrospectively reviewed consecutive cerebral aneurysms treated with open surgical treatment after failure of embolization from 2000 to 2022. All endovascular modalities were included. RESULTS: On average, 1362 aneurysms were treated annually in the 2 countries. The incidence increased from 0.006% in 2005 to 0.008% in 2020 in the overall population. Open surgery after failed endovascular intervention was necessary in 128 aneurysms (0.8%), a proportion that remained constant over time. Subarachnoid hemorrhage was the initial presentation in 70.3% of aneurysms. The most common location was the anterior communicating artery region (40.6%), followed by the middle cerebral artery (25.0%). The median diameter was 6 mm (2-32). Initial endovascular treatment included coiling (107 aneurysms), balloon-assist (10), stent-assist (4), intrasaccular device (3), flow diversion (2), and others (2). Complete occlusion after initial embolization was recorded in 40.6%. Seventy-one percent of aneurysms were operated within 3 years after embolization. In 7%, the indication for surgery was (re-)rupture and, in 88.3%, reperfusion. Device removal was performed in 16.4%. Symptomatic intraoperative and postoperative complications occurred in 10.2%. Complete aneurysm occlusion after open surgery was achieved in 94%. CONCLUSION: Open surgery remains a rare indication for cerebral aneurysms after failed endovascular embolization even in the age of novel endovascular technology, such as flow diverters and intrasaccular devices. Regardless, it is mostly performed for ruptured aneurysms initially treated with primary coiling that are in the anterior circulation.

Microsurgical Clipping after Failed Contour Device Embolization of an Anterior Communicating Artery Aneurysm: Technical Note.

BACKGROUND: Endovascular therapy has revolutionized the treatment of cerebral aneurysms in recent years and decades. So-called intrasaccular devices (i.e., Woven EndoBridge [WEB], MicroVention, Aliso Viejo, California, United States; or Contour, Cerus Neurovascular, Fremont, California, United States) are a promising endovascular technology, especially for wide-based aneurysms. However, long-term outcome data are currently particularly scarce for Contour and strategies for failed Contour cases are lacking. Here, we report the feasibility of microsurgical clipping after failed Contour device embolization. METHODS: Feasibility of microsurgical clipping after failed aneurysm embolization with a Contour intrasaccular device was assessed in a patient. RESULTS: We present the case of a 36-year-old male patient diagnosed with Hunt and Hess grade 1 subarachnoid hemorrhage from an anterior communicating artery aneurysm. The ruptured aneurysm was initially treated with the Contour device. After 3 months, angiographic imaging showed a clear aneurysm residual deemed not endovascularly accessible. The patient was then successfully clipped using microsurgical techniques. The patient was discharged with no neurologic abnormalities. CONCLUSION: After thorough bibliographical research, this presents the first published case report of microsurgical clipping after failed embolization with Contour. The main insights gained after clipping were that the Contour does not significantly disturb or hinder clipping. In contrast to coils in aneurysms to be clipped, the Contour can be easily compressed by the clip blades and does not have to be removed. In addition, the Contour had not migrated into the subarachnoid space and there was no abnormal scarring. Clipping appears to be a reasonable treatment strategy for failure of embolization with Contour if endovascular means are not suitable.

Middle cerebral artery aneurysm surgery after stent misplacement: A case report.

Stent misplacement during endovascular treatment of middle cerebral artery (MCA) aneurysms can cause challenges and be problematic, if clipping becomes necessary. This article reports on a 56-year-old woman with an unruptured, multi-lobulated MCA aneurysm, whom primarily refused surgery; therefore, she was scheduled for stent-assisted coiling. After successful deployment of the stent, it unfortunately then became snagged by the microcatheter and was pulled backwards. The subsequent surgical procedure (i.e. clipping of the MCA aneurysm) was challenging, due to the position of the dislodged stent. Such as misplacement of the stent is rarely documented: It resulted in the difficult handling of a MCA aneurysm. Aneurysms of the MCA should primarily be considered for surgical clipping. In conclusion, an increased risk for eventual surgery should be considered, in cases where endovascular treatments with stents are performed.