Complex Intracranial Aneurysms Research Articles

The Art of Cerebral Revascularization: An Illustrative Case Series of Bypass Techniques for Complex Intracranial Aneurysms

Complex intracranial aneurysms (CIAs) comprise a subset of lesions with defiant vascular architecture, difficult access, and prior treatment. Surgical management of CIAs is often challenging and demands an assessment on a case-by-case basis. The generational evolution of bypass surgery has offered a long-standing potential for effective cerebral revascularization. Herein, we aim to illustrate a single-center experience treating CIAs. The authors conducted a retrospective analysis of clinical records of patients treated with cerebral revascularization techniques at Hospital Nacional Dos de Mayo, Lima, Peru during 2018-2022. Relevant data were collected, including patient history, aneurysm features on imaging, preoperative complications, the intraoperative course, aneurysm occlusion rates, bypass patency, neurological function, and postoperative complications. Seventeen patients (70.59% female; median age: 53 years) with 17 CIAs (64.7% saccular; 76.5% ruptured) were included. The most common clinical presentation included loss of consciousness (70.6%) and headaches (58.8%). Microsurgical treatment included first, second, and third-generation bypass. In 47.1% of cases, an anastomosis between the superior temporal artery (STA) and the M3 segment was predominantly used, followed by an A3-A3 bypass (29.4%), STA-M2 bypass (17.6%), and an external carotid artery to M2 bypass (5.9%). The intraoperative aneurysm rupture rate was 11.8%. Postoperative complications included ischemia (40%), cerebrospinal fluid fistulas (26.7%), and pneumonia (20%). At hospital discharge, the median Glasgow Coma Scale score was 14 (range: 10-15). At the six-month follow-up, 82.4% of patients had a modified ranking scale (mRS) score ≤2, bypass patency was present in all cases, and the morbidity rate was 17.6%. CIAs represent a spectrum of defiant vascular lesions with a poor natural history. Bypass surgery offers the potential for definitive treatment. Our case series illustrated the predominant role of cerebral revascularization of CIAs with a critical case-by-case approach to provide optimal outcomes in a limited-resource setting.

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.

A CFD-based framework to evaluate surgical alternatives in cerebral aneurysms

ABSTRACT Computational Fluid Dynamic (CFD) simulations on patient-specific geometries may guide the choice between alternative surgical interventions, especially in the case on non-conventional treatments. We propose and formalise a CFD-based framework to evaluate alternative surgical interventions. It provides surgeons with the CFD analyses of different surgical options, so that they may decide the best strategy based on quantitative haemodynamic parameters for each surgical alternative. The proposed framework is largely automatised and, when it necessarily requires the intervention of a human operator due to the patient-specific nature, this intervention is well-formalised to reduce inter-operator variability and guarantee reproducibility. To provide preliminary evidence on the effectiveness of the framework, we present its application to complex Intracranial Aneurysms (IAs), which involve less than 5% of brain aneurysms, but are usually at a high risk of rupture and often show unexpected response to therapy. Complex IAs include aneurysms that cannot be treated with conventional therapies, such as neck clipping, sac coiling or stenting, while instead their treatment requires the sacrifice of the parent artery. In particular, we refer to a giant cavernous sinus aneurysm inside the left internal carotid artery. Results show the ability of the framework to provide haemodynamic quantitative evaluations, which can be useful additional information for the neurosurgeon towards optimal surgical planning.

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.

Tubridge flow diverter for the treatment of recurrent cerebral aneurysms

Background & Objective: The Tubridge flow diverter is a commonly used device in China for reconstructing the parental artery and occluding complex intracranial aneurysms. However, there is limited experience with the device in treating recurrent intracranial aneurysms. The purpose of this study is to assess the safety and effectiveness of the Tubridge flow diverter in treating recurrent single- coiling aneurysms. Methods: The clinical records of patients with recurrent intracranial aneurysms who were treated with a Tubridge flow diverter were reviewed to show the therapeutic process, occlusion rate, and clinical outcomes associated with this treatment method. Results: Five patients with recurrent aneurysms of the internal carotid artery after singe coiling were included in the study. The recurrent aneurysmal sac had a mean length and width of 8.34/4.30 mm. All five Tubridge flow diverters were implanted without any unfold failure. The last angiographic follow-up showed a complete occlusion rate of 100%. Five branch arteries were covered, and only one branch artery disappeared during follow-up. No cases of cerebral infarction or intracranial hemorrhage were found among the patients. Conclusions: Our initial findings indicate that the Tubridge flow diverter could be a reliable and successful method for treating recurring single-coil aneurysms. We observed that the branch arteries were well-preserved, and no patients experienced cerebral infarction or hemorrhage. However, further research is necessary to establish clear indications and potential complications through a multicenter randomized controlled trial with long-term follow-up.

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.

In situ interposition bypass for complex intracranial aneurysms: A single-center experience and efficacy analysis.

The purpose of this study was to investigate the application and efficacy analysis of in situ interposition bypass in complex intracranial aneurysms. This study retrospectively analyzed the clinical data of 21 patients with complex intracranial aneurysms treated with in situ interposition bypass grafting in the Department of Neurosurgery at Tianjin Huanhu Hospital from June 2015 to December 2022. The aneurysms were located in the middle cerebral artery in 16 cases, the anterior cerebral artery in 3 cases, the posterior cerebral artery in 1 case, and the posterior inferior cerebellar artery in 1 case. The interposition graft vessels were taken from the radial artery in 15 cases, the superficial temporal artery in 5 cases, and the occipital artery in 1 case. All patients underwent end-to-end anastomosis with in situ interposition bypass after aneurysm resection, including 13 cases of "I-shaped" type, 5 cases of "V-shaped" type, and 3 cases of "Y-shaped" type. Postoperative digital subtraction angiography (DSA) or computed tomography angiography (CTA) reviews were performed for all the patients, and modified Rankin Scale (mRS) score was used to assess patient prognosis. Three patients developed postoperative basal ganglia infarction and two of them recovered well. One case developed transient incomplete aphasia and one case developed mild hemiparesis, which recovered well after 3months. The remaining 16 patients did not develop new neurological deficits. Postoperative DSA or CTA showed that the anastomosis of the bypass graft and the graft vessels were patent, and all aneurysms were completely eliminated. Regular postoperative follow-up ranged from 3 to 89months, and no aneurysm recurred. The percentage of patients with mRS ≤ 2 at the final follow-up was 90.5%. Based on the experience of surgical treatment in our center, in situ interposition bypass technique is a safe and effective option for the treatment of some complex intracranial aneurysms.

Periprocedural management of patients presenting for neurointerventional procedures using flow diverters for complex intracranial aneurysms: An anesthetist's perspective - A narrative review.

Complex intracranial aneurysms pose significant challenges in the realm of neurointervention, necessitating meticulous planning and execution. This article highlights the crucial roles played by anesthetists in these procedures, including patient assessment, anesthesia planning, and continuous monitoring and maintaining hemodynamic stability, which are pivotal in optimizing patient safety. Understanding these complex procedures and their complications will aid the anesthetist in delivering optimal care and in foreseeing and managing the potential associated complications. The anesthetist's responsibility extends beyond the procedure itself to postprocedure care, ensuring a smooth transition to the recovery phase. Successful periprocedural anesthetic management in flow diverter interventions for complex intracranial aneurysms hinges on carefully orchestrating these elements. Moreover, effective communication and collaboration with the interventional neuroradiologist and the procedural team are emphasized, as they contribute significantly to procedural success. This article underscores the essential requirement for a multidisciplinary team approach when managing patients undergoing neurointerventions. In this collaborative framework, the expertise of the anesthetist harmoniously complements the skills and knowledge of other team members, contributing to the overall success and safety of these procedures. By providing a high level of care throughout the periprocedural period, anesthetists play a pivotal role in enhancing patient outcomes and minimizing the risks associated with these intricate procedures. In conclusion, the periprocedural anesthetic management of neurointervention using flow diverters for complex intracranial aneurysms is a multifaceted process that requires expertise, communication, and collaboration.

Angiographic and Clinical Outcomes of Various Techniques of Intracranial-to-Intracranial Bypass for Complex Cases with a Review of Pertinent Literature and Illustrated Cases

Determine the utility of intracranial-to-intracranial bypass (IIB) surgery for complex cases and bypass options. Eighteen IIB cases were included. Each case was classified as IIB with interposition grafts and non-interposition grafts. Clinical and angiographical status were evaluated pre- and postoperatively and at the last follow-up. Angiographic images were analyzed and schematically drawn. Postoperative angiography was used to measure the bypass patency and the presence of postoperative cerebral infarction. Recipient artery occlusion time of each bypass was measured. 14 cases were complex intracranial aneurysms (IAs), 1 case was vertebrobasilar dolichoectasia, and 3 cases were intracranial arterial steno-occlusive disease (ICAS). 10 patients had incidental discovered IAs, and 7 patients presented with neurological deficits due to ischemia or aneurysmal mass effects. 10 cases were IIB with interposition grafts, including 4 cases of superficial temporal artery (STA) and 6 cases of radial artery graft (RAG) bypass. Eight cases were IIB with non-interposition grafts, including 3 cases of in situ bypass, 1 case of reanastomosis, and 4 cases of reimplantation. The pre- and postoperative mRS were not changed or improved, and all the bypasses were patent. There was no mortality during the mean follow-up period of 50.0 months. Mean occlusion time of recipient artery was 59.5 min. Total 8 patients had postoperative cerebral infarction but almost recovered at the discharge period. With the proper selection of the IIB type, IIB surgery can be a suitable treatment option for some patients with complex IAs and ICAS when extracranial-to-intracranial bypass is not feasible.

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.

The surgical strategy and technical nuances of in situ side-to-side bypass for the management of complex intracranial aneurysms.

Despite continuous advances in microsurgical and endovascular techniques, the treatment of complex aneurysms remains challenging. Aneurysms that are dilemmatic for conventional clipping or endovascular coiling often require bypass as part of a strategy to reduce the risk of ischemic complications. In anatomically favorable sites, the intracranial-intracranial in situ bypass may be an appealing choice. This article details the surgical strategies, operative nuances, and clinical outcomes of this technique with a consecutive series in our department. A retrospective review of a prospectively maintained neurosurgical patient database was performed to identify all patients treated with side-to-side in situ bypass from January 2016 to June 2022. In total, 12 consecutive patients, including 12 aneurysms, were identified and included in the series. The medical records, surgical videos, neuroimaging studies, and follow-up clinic notes were reviewed for every patient. Of the 12 aneurysms, there were 5 middle cerebral artery aneurysms, 4 anterior cerebral artery aneurysms, and 3 posterior inferior cerebellar artery aneurysms. The morphology of the aneurysms was fusiform in 8 patients and saccular in the remaining 4 patients. There were 3 patients presented with subarachnoid hemorrhage. The treatment modality was simple in situ bypass in 8 cases and in situ bypass combined with other modalities in 4 cases. Bypass patency was confirmed in all cases by intraoperative micro-doppler probe and (or) infrared indocyanine green (ICG) video angiography intraoperatively and with digital subtraction angiography (DSA) or computed tomography angiography (CTA) postoperatively. None of the patients developed a clinically manifested stroke due to the procedure though a callosomarginal artery was intentionally removed in one patient. The median follow-up period was 16.2 months (6-36). All patients had achieved improved or unchanged modified Rankin scale scores at the final follow-ups. Cerebral revascularization technique remains an essential skill for the treatment of complex aneurysms. The in situ bypass is one of the most effective techniques to revascularize efferent territory when vital artery sacrifice or occlusion is unavoidable. The configuration of in situ bypass should be carefully tailored to each case, with consideration of variations in anatomy and pathology of the complex aneurysms.

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.

Treatment Modalities of Complex Anterior Circulation Intracranial Aneurysms

Background Complex intracranial aneurysms (CIAs) are the most technically demanding neurosurgical pathologies. Although extensive work and effort has been directed to the treatment of these challenging vascular lesions, no formal definition exists on what complex aneurysms are, and it is rather subjective to individual interpretation that an aneurysm receives such label. Aim of the Study The overall aim of the study is to assess the clinical outcomes of the different modalities in management of complex intracranial anterior circulation aneurysms and to try to set up a clear and concrete treatment algorithm for the management dilemma. Patients and Methods This study is a prospective observational study that included 40 patients. All patients were evaluated by an interdisciplinary conference consisting of neuroendovascular surgeons and vascular neurosurgeons for assessment of the therapeutic options and the suitability of endovascular and/or surgical treatment. Initially, study setting was supposed to be in Ain Shams University teaching hospitals, Egypt, King’s College Hospital, United Kingdom and Barrow’s Neurological institute, USA. Unfortunately, due to COVID-19 Pandemic, Cases from King’s College Hospital in London were only included. Results Twenty cases were managed surgically, while 18 were treated by different endovascular techniques. Both surgical and endovascular modalities were used as a hybrid approach to treat 2 cases. Recurrence of treated aneurysms was seen only in the endovascular modality. Four cases out of the 18 cases treated by endovascular techniques showed either residual or recurrence of the previously treated aneurysms. Four documented intervention related mortalities occurred during the first 6 months. Two cases out of the 4 were treated by endovascular techniques (balloon assisted coiling & parent vessel occlusion), one case was surgically treated by clip/wrap technique and the last mortality was seen in a case treated by the hybrid approach (Clipping+ flow diverter). Conclusion Complex intracranial aneurysms managed surgically showed less recurrence rate than those treated by different endovascular techniques. CIAs treated by endovascular modalities showed much lower length of hospital stay and better modified Rankin scale after 6 months. Complications rate and mortality rate were nearly similar in both groups and were usually related to the initial poor presentation with hight WFNS grade upon the initial ictus.

Hemodynamic Investigation of the Flow Diverter Treatment of Intracranial Aneurysm

Flow diverter stents (FDS) are increasingly used for the treatment of complex intracranial aneurysms such as fusiform, giant, or wide-neck aneurysms. The primary goal of these devices is to reconstruct the diseased vascular segment by diverting blood flow from the aneurysm. The resulting intra-aneurysmal flow reduction promotes progressive aneurysm thrombosis and healing of the disease. In the present study, a numerical investigation was performed for modeling blood flow inside a patient-specific intracranial aneurysm virtually treated with FDS. The aim of the study is to investigate the effects of FDS placement prior to the actual endovascular treatment and to compare the effectiveness of devices differing in porosity. Numerical simulations were performed under pulsatile flow conditions, taking into account the non-Newtonian behavior of blood. Two possible post-operative conditions with virtual stent deployment were simulated. Hemodynamic parameters were calculated and compared between the pre-operative (no stent placement) and post-operative (virtual stent placement) aneurysm models. FDS placement significantly reduced intra-aneurysmal flow velocity and increased the Relative Residence Time (RRT) on the aneurysm, thus promoting thrombus formation within the dilatation and aneurysm occlusion. The results highlighted an increase in the effectiveness of FDS as its porosity increased. The proposed analysis provides pre-operative knowledge on the impact of FDS on intracranial hemodynamics, allowing the selection of the most effective treatment for the specific patient.

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.