Treatment Of Complex Intracranial Aneurysms Research Articles

Intrasaccular Treatment of Intracranial Aneurysms: A Comprehensive Review

Background: The endovascular treatment of complex intracranial aneurysms, such as wide-neck aneurysms (WNAs), remains a challenge. More established endovascular techniques, which include balloon-assisted coiling, stent-assisted coiling, and flow diversion, all have their drawbacks. Intrasaccular flow disruptor devices have emerged as a useful tool for the neurointerventionalist. Methods: Here, we discuss landmark studies and provide a comprehensive, narrative review of the Woven EndoBridge (WEB; Microvention, Alisa Viejo, CA, USA), Artisse (Medtronic, Irvine, CA, USA), Contour (Stryker, Kalamazoo, MI, USA), Saccular Endovascular Aneurysm Lattice Embolization System (SEAL; Galaxy Therapeutics Inc, Milpitas, CA, USA), Medina (Medtronic, Irvine, CA, USA), and Trenza (Stryker, Kalamazoo, MI, USA) devices. Results: Intrasaccular devices have proven to be effective in treating complex aneurysms like WNAs. Conclusions: Intrasaccular flow disruptors have emerged as a new class of effective endovascular therapy, and results of ongoing clinical studies for the newer devices (e.g., SEAL and Trenza) are much anticipated.

Current Indications, Trends, and Long-Term Results of 233 Bypasses to Treat Complex Intracranial Aneurysms: A Location-Specific Analysis.

Advances in endovascular flow diverters have led to a secular shift in the management of brain aneurysms, causing debate on current bypass indications. We therefore sought to investigate the long-term results, current indications, and trends of bypasses for brain aneurysms. We retrospectively reviewed bypasses performed between 2005 and 2022 to treat brain aneurysms. Demographic, clinical, and radiological data were collected till the most recent follow-up. Aneurysm occlusion and graft patency was noted on cerebral angiogram in the immediate postoperative, 3-month, and most recent follow-up periods. Clinical outcomes (modified Rankin scores) and complications were assessed at 3 month and most recent follow-up. Trends in bypass volume and graft patency were assessed in 5-year epochs. Results were dichotomized based on aneurysm location to generate location-specific results and trends. Overall, 203 patients (mean age 50 years, 57% female patients) with 207 cerebral aneurysms were treated with 233 cerebral bypasses with a mean follow-up of 2 years. Fusiform morphology was the most common bypass indication. Aneurysm occlusion on immediate postoperative and final follow-up angiogram was 89% (184/207) and 96% (198/207), respectively. Graft patency rate in the immediate postoperative period and most recent follow-up was 95% (222/233) and 92% (215/233), respectively. Of 207 aneurysms, 5 (2%) recurred. Of 203 patients, 81% (165) patients had modified Rankin scores of 0-2 at the 3-month follow-up and 11 patients died (mortality 5%). Although there was a steady decrease in the bypass volume over the study period, the proportion of bypasses for recurrent aneurysms increased serially. Posterior circulation aneurysms had lower rates of aneurysm occlusion and significantly higher incidence of postoperative strokes and deaths (P = .0035), with basilar artery aneurysms having the worst outcomes. Bypass indications have evolved with the inception of novel flow diverters. However, they remain relevant in the cerebrovascular surgeon's armamentarium, and long-term results are excellent.

Technical success, procedural safety, and efficacy of the Silk Vista Baby in the treatment of cerebral aneurysms over a mid-to-long-term follow-up.

Long-term follow-up of cerebral aneurysms treated with the Silk Vista Baby (SVB) flow diverter is lacking. This study aimed to assess the technical success, procedural safety, and efficacy of the SVB (Balt, Montmorency, France) for the treatment of intracranial aneurysms in small cerebral vessels over a mid-to long-term follow-up. We retrospectively analyzed a prospectively maintained database of patients treated with the SVB between September 2018 and June 2021. Data regarding patient demographics, aneurysm characteristics, and technical procedures were also collected. Angiographic and clinical findings were recorded during the procedure and over a period of at least 12 months. Angiographic and clinical follow-up data were available for 50 patients/50 aneurysms. The procedural complication rate was 8%. At 12 months, the final results showed a technical success rate of 100%, the re rupture rate was 0%, neuromorbidity and mortality rates of 4 and 0%, respectively, and an almost complete occlusion rate of 94%. Treatment of complex intracranial aneurysms with the SVB was safe and effective. Long-term results showed high rates of adequate and stable occlusions.

Sacrificing Internal Carotid Artery-External Carotid Artery-Radial Artery-Middle Cerebral Artery Bypass for the Treatment of Complex Intracranial Artery Cavernous Sinus Aneurysms.

The treatment of complex intracranial aneurysms has always been a great challenge in neurosurgery. Craniotomy has a high risk of clipping, there is a risk of rupture at any time, endovascular embolization is relatively low risk, but expensive and easy to relapse, the best treatment needs to be further discussed. Cavernous sinus aneurysms with pituitary adenomas are rare. This case reports a case of complex intracranial aneurysms. Chief complaints are: (1) blepharoptosis with blurred vision for 1 year, (2) headache for 3 days, and (3) digital subtraction angiography showed right internal carotid artery cavernous sinus aneurysm. Combined with the patient's condition and family condition, the external carotid artery-radial artery-middle cerebral artery bypass was selected. After surgical treatment, the symptoms of the patients were improved, the postoperative recovery was good, and the condition was stable. After follow-up, the patient's brain computed tomography showed intra-aneurysm thrombosis.

Intracranial-intracranial bypass strategies for the treatment of complex intracranial aneurysms: anatomical characteristics and surgical intervention.

The effectiveness of revascularization for complex aneurysms is well-established. This study aimed to describe the technical characteristics and clinical efficacy of intracranial-to-intracranial (IC-IC) bypass for the treatment of complex intracranial aneurysms. We retrospectively reviewed all patients with aneurysms who underwent a preplanned combination of surgical or endovascular treatment and IC-IC bypass at our institution between January 2006 and September 2023. IC-IC bypass techniques included four strategies: type A (end-to-end reanastomosis), type B (end-to-side reimplantation), type C (in situ side-to-side anastomosis), and type D (IC-IC bypass with a graft vessel). During the study period, ten patients with aneurysms each underwent IC-IC bypass surgery. Aneurysms were located in the middle cerebral artery (60.0%), anterior temporal artery (10.0%), anterior cerebral artery (20.0%), and vertebral artery (10.0%). There were three saccular aneurysms (30.0%), two fusiform aneurysms (20.0%), one dissecting aneurysm (10.0%), and four pseudoaneurysms (40.0%). We performed the type A strategy on five patients (50.0%), type B on one (10.0%), type C on one (10.0%), and type D on three (30.0%). During a mean period of 68.3months, good clinical outcomes (modified Rankin Scale score, 0-2) were observed in all patients. Follow-up angiography demonstrated complete aneurysmal obliteration in all patients and good bypass patency in nine of ten patients (90.0%). The treatment of complex aneurysms remains a challenge with conventional surgical or endovascular treatments. IC-IC bypass surgery is a useful technique, associated with favorable clinical outcomes, for treating complex aneurysms.

Intracranial-intracranial bypass strategies for the treatment of complex intracranial aneurysms: Anatomical characteristics and surgical intervention

Intracranial-intracranial bypass strategies for the treatment of complex intracranial aneurysms: Anatomical characteristics and surgical intervention

Optimizing the Approach to STA-MCA Bypass Surgery and Reducing Wound Complications

The treatment of complex intracranial aneurysms with bypass surgery using 2 branches of the superficial temporal artery (STA) proves to be an effective surgical option. However, the harvest of these 2 STA branches, combined with a pterional craniotomy, carries the potential risk of delayed wound healing of the skin flap. This study undertook a retrospective analysis to examine and identify the factors associated with this delayed wound healing. A total of 56 consecutive cases, including both ruptured and unruptured complex intracranial aneurysms, that underwent bypass surgery with 2 branches of the STA, were analyzed retrospectively. Major delayed wound healing was observed in 6 (10.7%) cases. Univariate analysis demonstrated significant associations with the following factors: rupture (P= 0.023), presence of diabetes mellitus (P= 0.028), large craniotomy size (P= 0.012), and the type of skin incision (P ≤ 0.001). Age (P= 0.283), sex (P= 0.558), body mass index (P= 0.221), and other blood test parameters did not demonstrate any statistical significance. Similarly, the presence of a dominant frontal branch (P= 0.515) or a low-positioned frontal branch (P= 0.622) did not reveal statistically significant results. In the treatment of complex intracranial aneurysms, where harvesting of the 2 STA branches is involved with a pterional craniotomy, producing a smaller skin flap (L- or T-shaped incision) is effective in minimizing the risk of delayed wound healing. The process of harvesting the STA and closing the wound demands meticulous care, taking into consideration the normal anatomical structures and the subdermal vascular plexus of the scalp.

Superficial temporal artery interposition bypass for the treatment of complex intracranial aneurysms: Flexible and creative options for flow preservation bypass

PurposeFlow-preservation bypass is a treatment option for complex intracranial aneurysms (IAs) that cannot be managed with microsurgical clipping or endovascular treatment. Various bypass methods are available, including interposition grafts such as the radial artery or saphenous vein. Size discrepancy, invasiveness, and procedure complexity must be considered when using interposition grafts. We describe our experience of treating complex IAs using a superficial temporal artery (STA) interposition bypass. MethodsWe retrospectively reviewed the medical records and operative videos of all patients who were treated for complex IAs at our center from January 2009 to December 2021 using cerebral revascularization. Clinical, radiological, and surgical findings of the cases that underwent STA interposition bypass were investigated. ResultsSeventy-six bypass procedures were performed of which seven (9.2%) complex IAs were managed using STA interposition bypass. Of these 5 cases were of anterior cerebral artery, 1 of middle cerebral artery, and 1 of posterior inferior cerebellar artery aneurysm. There were no postoperative ischemic complications. Revision surgery for postoperative pseudomeningocele was performed in one case. The long-term bypass patency rate was 85.7% (6 out of 7) and good long-term aneurysm control was achieved in all cases, with a mean follow-up of 64 months. ConclusionsWhen treating complex IAs, creative revascularization strategies are needed in selective cases for favorable outcomes. STA interposition graft bypass which can reduce the size discrepancy between the donor and recipient may be a less invasive, flexible, and practical option for treating complex IAs.

Safety and effectiveness of the LVIS and LVIS Jr devices for the treatment of intracranial aneurysms: Final results of the LEPI multicenter cohort study

BackgroundThe Low profile visualized intraluminal support (LVIS)/LVIS Jr is a self-expanding braiding stent for the treatment of intracranial aneurysm. This study is to determine the safety and effectiveness of the LVIS/LVIS Jr for the treatment of intracranial aneurysms in a real-world setting. MethodsThis prospective, observational, multicenter study enrolled patients with unruptured, ruptured and recanalized intracranial aneurysms treated with the LVIS stents, between February 2018 to December 2019. Primary endpoint was the cumulative morbidity and mortality rate (CMMR) assessed at 12 months follow-up (FU). ResultsA total of 130 patients were included (62.3 % women, mean age 55.9 ± 11.4) on an intention-to-treat basis. Four patients (3.1 %) had 2 target aneurysms; 134 total aneurysms were treated. The aneurysms were mainly located on the middle cerebral artery (41/134; 30.6 %) and the anterior communicating artery (31/134; 23.1 %). The CMMR at 1 year linked to the procedure and/or device was 4.6 % (6/130). The overall mortality was 1.5 % (2/130), none of these deaths adjudged as being linked to the procedure and/or device. All aneurysms (134/134, 100 %) were successfully treated with LVIS stent and/or other devices. At a mean FU of 16.8 months post-procedure, complete/nearly complete occlusion was achieved in 112 aneurysms (92.6 %), and only 3 patients (2.5 %) required aneurysm retreatment. ConclusionThis study provides evidence that the LVIS/LVIS Jr devices are safe and effective in the treatment of complex intracranial aneurysms, with very high rates of adequate occlusion at FU. These angiographic results are stable over time with an acceptable complication rate.Trial Registration: ClinicalTrial.gov under NCT 03553771.

Safety and efficacy of the fourth-generation Acandis Acclino flex plus stent for the treatment of complex intracranial aneurysms.

The low-profile Acandis Acclino flex plus (AFP) is a fourth-generation laser-cut microstent with a flexible structure designed for the treatment of a wide variety of aneurysms. We report our single-center experience with this device in the treatment of complex aneurysms. Twenty-eight patients were treated with the Acclino flex plus for 28 aneurysms. Aneurysm characteristics, technical success, complications, clinical outcome, and angiographic results were retrospectively analyzed. The cohort included 8 unruptured untreated aneurysms, 9 unruptured recurrent aneurysms, and 12 ruptured aneurysms with aneurysm diameters ranging from 3 to 23 mm. The anterior communicating artery was the most common location (52%). Stent deployment was successful in 28 cases (97%) with an average of 1.3 stents per aneurysm. The overall procedural complication rate was 17%, including 2 (6.8%) major clinical events (one ischaemic stroke and one aneurysm perforation) and one (3.4%) minor clinical event (one seizure). Angiographic results of 23 aneurysms at a mean of 6 months were complete occlusion in 74%, neck remnants in 13% and aneurysm remnants in 13%. Three patients were retreated. Given the complexity of the aneurysms, the use of the Acclino flex plus was feasible and associated with a favourable safety and efficacy profile. Further studies are needed to evaluate Acclino flex plus in other aneurysm subsets and to define its role in endovascular aneurysm treatment.

A review and journey in intrasaccular treatment of intracranial aneurysms.

The invested effort and collaboration of clinicians and medical device companies to improve occlusion rates and clinical outcomes for patients with intracranial aneurysms treated via less invasive endovascular means led to the development of the concept of intrasaccular devices. Intrasaccular devices were introduced to offer simple treatment options, offering easier navigation through difficult anatomy, simpler and quicker deployment into large and wide-neck aneurysms. Additionally, they offer easier sizing, whilst offering a wide range of options suitable for aneurysms of different sizes. The concept of most intrasaccular devices is to occupy the aneurysm neck, however offering better stability than simple coiling, therefore increasing the chance of long-term aneurysm occlusion. This is achieved without a sizable metal content within the parent vessel, contrary to flow diverters, theoretically reducing the risk of thromboembolic events. This review aims to discuss the history and latest developments of intrasaccular intracranial devices, which offer an exciting and potentially successful option for treatment of complex intracranial aneurysms.

Flow Diversion for Intracranial Aneurysms in Large‐Diameter Vessels: A Subanalysis From the SESSIA Study

Background Flow diverters are now considered first‐line tools for treating intracranial aneurysms. However, few devices are available for patients with large‐diameter vessels (LDVs). Hence, we evaluated the performance of the largest diameter Surpass Streamline for aneurysms in LDVs. Methods We performed a subanalysis of the SESSIA (Safety and Efficacy of the Surpass Streamline for Intracranial Aneurysms) multicenter cohort study of patients treated with Surpass Streamline between 2018 and 2021. Patients in whom a 5‐mm diameter Surpass Streamline was implanted were divided into 2 groups according to vessel diameter at the landing zones (LDV, ≥5.3 mm versus non‐LDV [N‐LDV], <5.3 mm). Efficacy was complete occlusion at final follow‐up. Safety was ischemic/hemorrhagic events and mortality up to 30 days. Results Thirty patients harboring 30 aneurysms were included. Fifteen cases were included per group (LDV versus N‐LDV). Baseline demographics, clinical characteristics, median aneurysm size (LDV, 11 mm versus N‐LDV, 10 mm), and location were similar. Vessel diameters at the proximal (LDV, 5.3 mm versus N‐LDV, 4.2 mm; P <0.001) and distal (5.6 versus 4.0 mm; P <0.001) flow diverter landing zones were different. Procedural characteristics (including balloon‐assisted angioplasty and stenting) were similar. At the final follow‐up (12±6 months), complete occlusion (LDV, 75% versus N‐LDV, 84%; P =0.548), and ischemic/hemorrhagic events (1 per group; P =1.00) were not different. Conclusions The use of large‐diameter flow diverters for treating complex intracranial aneurysms arising in LDVs is technically feasible and safe. Comparative studies evaluating devices suitable for this patient population will provide valuable insights for the best device selection.

Application of protective superficial temporal artery to middle cerebral artery bypass through the lateral supraorbital approach: Technical note

ObjectiveThe lateral supraorbital (LSO) approach is a minimally invasive craniotomy widely used in the surgical treatment of intracranial aneurysms (IAs). A protective bypass is considered a safety measure in high-risk and complex clipping procedures to maintain distal cerebral flow. However, the protective bypass has so far only been applied through a pterional or larger craniotomy. We aimed to describe the characteristics of the superficial temporal artery to middle cerebral artery (STA-MCA) bypass through the LSO craniotomy to treat complex IAs. MethodsWe retrospectively identified six patients with complex IAs who underwent clipping and a protective STA-MCA bypass through the LSO approach between January 2016 and December 2020. The STA donor artery was harvested through the same curvilinear skin incision with a small extension, and it was anastomosed to the opercular segment of the MCA. Subsequently, aneurysm clipping followed standardized steps. ResultsAnastomosis was successful in all patients. Despite requiring temporary occlusion of the parent artery, all aneurysms were successfully clipped without any neurological deterioration. ConclusionsA protective STA-MCA bypass is feasible through the LSO approach with certain technical modifications. This technique helps protect distal cerebral flow for safe clip placement in the treatment of complex IAs with the associated benefits of a less invasive craniotomy.

Combined Double-Barrel Superficial Temporal Artery to M4 Bypass and Parent Artery Occlusion for the Treatment of Complex Intracranial Aneurysms in Internal Carotid Artery and Middle Cerebral Artery: A Retrospective Case Series.

Very little research has been conducted to assess the efficacy of combined double-barrel superficial temporal artery (STA) to M4 bypass and parent artery occlusion (PAO) in the treatment of complex intracranial aneurysms. To determine whether this operation could become a reasonable flow replacement therapy and have longer-term benefits. A series of double-barrel STA-M4 bypasses performed between 2016 and 2021 were reviewed. Preoperative digital subtraction angiography (DSA), computed tomography angiography (CTA), computed tomography perfusion (CTP), and balloon test occlusion were routinely performed for a thorough evaluation of individual benefits and risks. After bypass, the proximal end of the parent artery was permanently occluded with the coil. Augmentation and patency of STA were reassessed by postoperative DSA, CTA, and CTP. The blood flow volume of STA was measured by ultrasound at admission and a 3-month follow-up. This study included 12 consecutive patients (5 males, 7 females) who successfully underwent double-barrel STA-M4 bypass, including 8 complex aneurysms in the internal carotid artery (ICA) and 4 in the middle cerebral artery (MCA). Postoperative angiography and CTP suggested that all the STAs were patent, and there was a significant improvement in perfusion after the operation ( P < .05). Ultrasonic measurement at the 3-month follow-up showed that the blood flow provided by STA was 76.3 to 190.5 mL/min. Postoperative ischemia was found in 1 patient, but she recovered after treatment. Double-barrel STA to M4 bypass can provide adequate flow for the parent artery area, which may be a reasonable flow replacement therapy for some complex intracranial aneurysms in ICA and MCA.

Silk + flow-diverter stent for the treatment of intracranial aneurysms associated with balloon angioplasty: A retrospective study.

The silk + flow-diverter stent is increasingly used to treat complex intracranial aneurysms including wide-neck and fusiform aneurysms. Balloon angioplasty has been used to better appose the flow diverter (FD) to the vessel wall and, thus, improve aneurysm occlusion rates and decrease periprocedural complications. Sparse data are available concerning the results of this technique. We report our experience with silk + FD associated with balloon angioplasty for the treatment of intracranial aneurysms. A retrospective study was conducted on all patients treated by the silk + FD. Clinical charts, procedural data, and angiographic results were reviewed and compared between those treated with balloon angioplasty. A multivariate analysis was conducted to identify predictors of complications, occlusion, and outcome. Between July 2014 and May 2016, we identified 209 patients with 223 intracranial aneurysms. There were 176 (84.2%) women and 33 (15.8%) men. The most common stent size used was 4.5 mm in 101 patients (46.1%), followed by 4 mm in 57 patients (26%). Univariate analysis observed that stent diameter was significantly related to aneurysm occlusion (P < 0.05). Patients with more than 1 aneurysm treated with silk + stent have a 9.07 times greater chance of having complications in the procedure than patients with only 01 aneurysm (OR = 9.07; P = 0.0008). Patients who had angioplasty without the use of a balloon have a 13.69-times-higher risk of complications (OR = 13.69; P = 0.0003). Older age, larger aneurysms, and the use of more than 1 FD device were predictors of recanalization. Endovascular treatment of intracranial aneurysms with the silk + FD associated with balloon angioplasty is a safe and effective therapeutic option. Balloon angioplasty in combination with FD lowers the risk of complications. Higher complication rates and worse outcomes are associated with older age and large aneurysms.

Combined open revascularization and endovascular treatment of complex intracranial aneurysms: case series.

The treatment of complex intracranial aneurysms can be challenging with stand-alone open or endovascular techniques, particularly after rupture. A combined open and endovascular strategy can potentially limit the risk of extensive dissections with open-only techniques, and allow for aggressive definitive endovascular treatments with minimized downstream ischemic risk. Retrospective, single-institution review of consecutive patients undergoing combined open revascularization and endovascular embolization/occlusion for complex intracranial aneurysms from 1/2016 to 6/2022. Ten patients (4 male [40%]; mean age 51.9 ± 8.7 years) underwent combined open revascularization and endovascular treatment of intracranial aneurysms. The majority of aneurysms, 9/10 (90%), were ruptured and 8/10 (80%) were fusiform in morphology. Aneurysms of the posterior circulation represented 8/10 (80%) of the cases (vertebral artery [VA] involving the posterior inferior cerebellar artery [PICA] origin, proximal PICA or anterior inferior cerebellar artery/PICA complex, or proximal posterior cerebral artery). Revascularization strategies included intracranial-to-intracranial (IC-IC; 7/10 [70%]) and extracranial-to-intracranial (EC-IC; 3/10 [30%]) constructs, with 100% postoperative patency. Initial endovascular procedures (consisting of aneurysm/vessel sacrifice in 9/10 patients) were performed early after surgery (0.7 ± 1.5 days). In one patient, secondary endovascular vessel sacrifice was performed after an initial sub-occlusive embolization. Treatment related strokes were diagnosed in 3/10 patients (30%), largely from involved or nearby perforators. All bypasses with follow-up were patent (median 14.0, range 4-72 months). Good outcomes (defined as a Glasgow Outcomes Scale ≥4 and modified Rankin Scale ≤2) occurred in 6/10 patients (60%). A variety of complex aneurysms not amenable to stand-alone open or endovascular techniques can be successfully treated with combined open and endovascular approaches. Recognition and preservation of perforators is critical to treatment success.

Safety and effect of pipeline flex embolization device for complex unruptured intracranial aneurysms

To investigate the safety and short-term effect of Pipeline Flex devices in the treatment of complex unruptured intracranial aneurysms, a retrospective study was performed for patients with complex unruptured intracranial aneurysms who were treated with the Pipeline Flex embolization device (PED Flex device) combined with or without coiling. The clinical, endovascular, and follow-up data were analyzed. One hundred and thirty-one patients with 159 complex unruptured cerebral aneurysms were treated with the PED Flex device, with 144 Flex devices deployed. Periprocedural complications occurred in four patients, resulting in the complication rate of 3.1%, including ischemic complications in three patients (2.3%) and hemorrhagic complication in one (0.8%). At discharge, the mRS was 0 in 101 (77.1%) patients, 1 in 25 (19.1%), 2 in four (3.1%), and 4 in one (0.8%), with the good prognosis rate (mRS 0–2) of 99.2%. Clinical follow-up was carried out in 87 (66.4%) patients 3–42 months after the procedure, with the mRS of 0 in 78 (89.7%), 1 in five (5.7%), 2 in three (3.4%), and 4 in one (1.1%). No significant (P = 0.16) difference existed in the mRS at discharge compared with that at clinical follow-up. Angiographic follow-up was performed in 61 (46.7%) patients with 80 (50.3%) aneurysms at 3–40 months, with the OKM grade of D in 57 (71.3%) aneurysms, C in eight (10%), and B in 15 (18.8%). Asymptomatic instent stenosis occurred in four patients (6.6%). In conclusion: The treatment of complex intracranial aneurysms with the Pipeline Flex embolization device may be safe and effective, with a high complete occlusion rate, a decreased complication rate, and a good prognosis rate at medium follow-up.

Abstract Number ‐ 140: Transcranial Doppler Emboli Monitoring for Stroke Prevention after Flow Diversion: A Single Center Experience

Introduction Following the favorable clinical and radiographical results of flow diversion, its use has continually expanded for the treatment of complex intracranial aneurysms. The high metal surface of flow diverters (FD) increases the risk of thromboembolic complications. Current emboli monitoring data after FD placement is limited. Transcranial doppler (TCD) offers a non‐invasive evaluation of microembolic signals and might be a valuable tool to prevent ischemic complications. We evaluated the rate of embolic signals and their management after FD implantation. Methods We performed a retrospective, single‐center evaluation of adult patients who underwent a FD procedure with the Pipeline Embolization Device (PED) for unruptured intracranial aneurysms between 2012 and 2016. Covariates included patient demographics, comorbidities, aneurysm characteristics, procedure characteristics, and post‐procedure TCD emboli monitoring (immediate and &gt;12 hours post‐operative). TCD emboli signals were classified as positive (&lt; 15 microembolic signals) and strongly positive (&gt;15 signals). The primary outcome was the rate of symptomatic stroke at 2 and 12 weeks in these patients. Results 105 patients with 132 aneurysms were analyzed. Mean age was 59.7 years, and 78% were females. Mean aneurysm size was 7.8 ± 6.4 mm. Most of them were located in the paraclinoid region (40%). Two PEDs were implanted in 12 (11%) cases and adjunctive coiling was performed in 15 (14%) cases. Microemboli were detected in 11.4% of cases (12/105 patients) after PED deployment. In 5/12 patients, the emboli resolved upon repeat testing with no intervention. In 6/12 patients, further heparinization, additional clopidogrel administration, or change in antiplatelet agents were needed. These treatments reduced the microembolic events. In 1 patient who was clopidogrel‐resistant and a ticagrelor super‐responder, mechanical thrombectomy was necessary due to acute in‐stent thrombosis. There were no symptomatic strokes at 2 and 12 weeks. Conclusions TCD emboli monitoring can be a powerful non‐invasive tool for the early identification and prevention of thromboembolic events after FD implantation. Early detection of microembolic signals offers the possibility to modify postoperative management, avoid silent emboli, and potentially avoid symptomatic strokes.

Abstract Number ‐ 43: Flow Diversion for Intracranial Aneurysms in Large Caliber Vessels: A Case Series

Introduction The safe and effective profile of flow diverters (FD) has allowed neuro‐interventionalists to consider them as a versatile tool for the treatment of aneurysms with different morphologies, locations, and characteristics. Optimal deployment with complete wall apposition affects FD performance. However, few devices are suitable for aneurysms in large caliber vessels. Herein, we aimed to describe the safety and efficacy of a large caliber (5 mm) FD for the treatment of intracranial aneurysms. Methods We performed a retrospective, multi‐center cohort study of adult patients in whom a 5 mm Surpass Streamline FD was implanted between 2018 and 2021 in the United States. Efficacy outcome was complete occlusion at final follow‐up. Safety outcomes were ischemic/hemorrhagic events and mortality up to 30 days following the procedure. Secondary safety was assessed by the rate of adjunctive devices/treatments to overcome technical complications and improve wall apposition. Results A total of 29 patients harboring 29 aneurysms were treated with 39 FDs (36 large‐diameter devices). Mean age was 57.8 ± 15.7 years. Aneurysm morphologies were saccular (n = 15), pseudoaneurysm (n = 7), fusiform (n = 6), and dissecting (n = 1). Locations were internal carotid artery (ICA) petro‐cavernous segment (n = 15), ICA paraophthalmic (n = 5), ICA cervical (n = 4), basilar artery (n = 3), and vertebral artery (n = 2). Aneurysm size mean was 11.4 ± 6.7 mm, and neck size mean 6.5 ± 3.9 mm. Proximal FD landing zone vessel diameter was 4.8 ± 1.3 mm and distal 4.5 ± 1.2 mm. At a mean final follow‐up of 12 ± 6 months, 18 (65%) aneurysms were completely occluded. Ischemic/hemorrhagic events occurred in 2 (7%), and 1 patient died during hospitalization. Balloon‐assisted angioplasty was performed in 19 (66%) cases, adjunctive stenting in 8 (28%), and coiling in 1 (3%). Patients who received an adjunctive device/treatment had an 82% (14/17) complete occlusion compared to 66% (4/6) in those who did not. Conclusions The use of large caliber FDs to treat complex intracranial aneurysms located in large‐diameter dysplastic vessels is technically feasible and safe. The use of adjunctive devices and techniques to achieve optimal wall apposition seems crucial to optimize treatment outcomes. Comparative studies with devices specially designed for this patient population might provide further insights into the best device selection.

Roadmapping technique in the hybrid operating room for the microsurgical treatment of complex intracranial aneurysms.

To describe the roadmapping technique and our three-year experience in the management of intracranial aneurysms in the hybrid operating room. We analyzed all patients who underwent surgical clipping for cerebral aneurysms with the roadmapping technique from January 2017 to September 2019. We report demographic, clinical, and morphological variables, as well as clinical and radiological outcomes. We further describe three illustrative cases of the technique. A total of 13 patients were included, 9 of which (69.2%) presented with subarachnoid hemorrhage, with a total of 23 treated aneurysms. All patients were female, with a mean age of 47.7 years (range 31-63). All cases were anterior circulation aneurysms, the most frequent location being the ophthalmic segment of the internal carotid artery (ICA) in 11 cases (48%), followed by posterior communicating in 8 (36%), and ICA bifurcation in 2 (8%). Intraoperative clip repositioning was required in 9 aneurysms (36%) as a result of the roadmapping technique in the hybrid operating room. There were no residual aneurysms in our series, nor reported mortality. The roadmapping technique in the hybrid operating room offers a complementary tool for the adequate occlusion of complex intracranial aneurysms, as it provides a real time fluoroscopic-guided clipping technique, and clip repositioning is possible in a single surgical stage, whenever a residual portion of the aneurysm is identified. This technique also provides some advantages, such as immediate vasospasm identification and treatment with intra-arterial vasodilators, balloon proximal control for certain paraclinoid aneurysms, and simultaneous endovascular treatment in selected cases during a single stage.