The role of endovascular treatment in unruptured basilar tip aneurysms

Thromboembolic Events in the Posterior Circulation After Flow Diversion-A Closer Look at Coverage of the Posterior Cerebral Artery

BACKGROUND

Flow diversion for bifurcation aneurysms requires excluding one of the branches from the parent artery, raising concern for ischemic events. We evaluated thromboembolic events and their relationship with covering the origin of the posterior cerebral artery (PCA).

METHODS

This retrospective analysis included patients with confirmed basilar and proximal PCA aneurysms treated with flow diversion between 2013 and 2023. Procedures were classified according to the coverage of the origin of the PCA. Thromboembolic events associated with the excluded PCA were evaluated.

RESULTS

Of the total 28 aneurysms included, 7 were at the basilar tip, 16 in the basilar trunk, and 5 in the first segment of the PCA; 15 were treated by excluding one of the PCAs. Dual antiplatelet therapy included aspirin and ticagrelor (57.1%), aspirin and clopidogrel (35.7%), or aspirin and prasugrel (3.57%). Complete and near-complete aneurysm occlusion was achieved in 80.8% of the aneurysms treated at a median follow-up of 12.31 months. Thromboembolic complications occurred in 3 patients (2 with basilar perforator stroke and 1 with basilar in-stent thrombosis). However, the difference in these events was not statistically significant between patients with PCA coverage and those without (P = 0.46). Diminished flow and a lack of flow was seen in 8 and 7 of the covered vessels, respectively. A modified Rankin scale score of ≤2 was reported for 89.3% of patients at a median clinical follow-up of 5.5 months.

CONCLUSIONS

The incidence of thromboembolic events is high in distal basilar and proximal PCA aneurysms; however, PCA coverage was not associated with their occurrence. There was no difference in postprocedural disability between patients whose aneurysms were treated by excluding one of the PCAs and those who were not.

Systematic Review and Meta-Analysis of Endovascular Therapy Effectiveness for Unruptured Saccular Intracranial Aneurysms

Background

Currently, endovascular treatment of intracranial aneurysms (ICAs) is limited by low complete occlusion rates. The advent of novel endovascular technology has expanded the applicability of endovascular therapy; however, the superiority of novel embolic devices over the traditional Guglielmi detachable coils (GDCs) is still debated. We performed a systematic review of literature that reported Raymond-Roy occlusion classification (RROC) rates of modern endovascular devices to determine their immediate and follow-up occlusion effectiveness for the treatment of unruptured saccular ICAs.

Methods

A search was conducted using electronic databases (PUBMED, Cochrane, ClinicalTrials.gov, Web of Science). We retrieved studies published between 2000-2022 reporting immediate and follow-up RROC rates of subjects treated with different endovascular ICA therapies. We extracted demographic information of the treated patients and their reported angiographic RROC rates.

Results

A total of 80 studies from 15 countries were included for data extraction. RROC rates determined from angiogram were obtained for 21,331 patients (72.5% females, pooled mean age: 58.2 (95% CI: 56.8-59.6), harboring 22,791 aneurysms. The most frequent aneurysm locations were the internal carotid artery (46.4%, 95% CI: 41.9%-50.9%), the anterior communicating artery (26.4%, 95% CI: 22.5%-30.8%), the middle cerebral artery (24.5%, 95% CI:19.2%-30.8%) and the basilar tip (14.4%, 95% CI:11.3%-18.3%). The complete occlusion probability (RROC-I) was analyzed for GDCs, the Woven EndoBridge (WEB), and flow diverters. The RROC-I rate was the highest in balloon-assisted coiling (73.9%, 95% CI: 65.0%-81.2%) and the lowest in the WEB (27.8%, 95% CI:13.2%-49.2%). The follow-up RROC-I probability was homogenous in all analyzed devices.

Conclusions

We observed that the coil-based endovascular therapy provides acceptable rates of complete occlusion, and these rates are improved in balloon-assisted coils. Out of the analyzed devices, the WEB exhibited the shortest time to achieve >90% probability of follow-up complete occlusion (~18 months). Overall, the GDCs remain the gold standard for endovascular treatment of unruptured saccular aneurysms.

Trends in the Age of Patients Treated for Unruptured Intracranial Aneurysms from 1990 to 2020

BACKGROUND

The decision for treatment for unruptured intracranial aneurysms (UIAs) is often difficult. Innovation in endovascular devices have improved the benefit-to-risk profile especially for elderly patients; however, the treatment guidelines from the past decade often recommend conservative management. It is unknown how these changes have affected the overall age of the patients selected for treatment. Herein, we aimed to study potential changes in the average age of the patients that are being treated over time.

METHODS

A systematic search of the literature was performed to identify all studies describing the age of the UIAs that were treated by any modality. Scatter diagrams with trend lines were used to plot the age of the patients treated over time and assess the presence of a potential significant trend via statistical correlation tests.

RESULTS

A total of 280 studies including 83,437 UIAs treated between 1987 and 2021 met all eligibility criteria and were entered in the analysis. Mean age of the patients was 55.5 years, and 70.7% were female. There was a significant increasing trend in the age of the treated patients over time (Spearman r: 0.250; P < 0.001), with a 1-year increase in the average age of the treated patients every 5 years since 1987.

CONCLUSIONS

The present study indicates that based on the treated UIA patient data published in the literature, older UIAs are being treated over time. This trend is likely driven by safer treatments while suggesting that re-evaluation of certain UIA treatment decision scores may be of great interest.

A review of the top 100 most influential articles on basilar artery aneurysms

Basilar artery aneurysms account for approximately 5% of all intracranial aneurysms. This bibliometric analysis summarizes the most-cited articles on basilar artery aneurysms and highlights the contributing articles to today's evidence-based practice. In the execution of this bibliometric-based review article, the Scopus database was used to perform a title-specific, keyword-based search for all publications until August 2022. The keyword "basilar artery aneurysm" or "basilar aneurysm" was used. Our results were arranged in descending order based on the article's citation count. The 100 most cited articles were selected for analysis. Parameters included the following: title, citation count, citations per year, authors, specialty of first author, institution, country of origin, publishing journal, Source Normalized Impact Per Paper (SNIP), and Hirsch index. The keyword-based search showed that 699 articles were published between 1888 and 2022. The top 100 articles were published between 1961 and 2019. The top 100 most cited articles collected a total of 8869 citations with an average of 89 citations per paper. The rate of self-citations accounted for an average of 4.85% of the total number of citations. The bibliometric analysis provides a quantitative overview of how medical topics and interventions are analyzed in academic medicine. In the present study, we evaluated the global trends in basilar artery aneurysms by finding the top 100 most cited papers.

Transcavernous Approach in Vascular Neurosurgery

The cavernous sinus is no more considered no man's land. It is a very well organized anatomic entity that can safely be navigated. It is both a route and a destination. Unlocking the cavernous sinus provides a highway that can be used to reach different vascular and tumor locations that were deemed very risky to handle.

Basilar apex aneurysm systematic review: Microsurgical versus endovascular treatment

BACKGROUND

Both microsurgical and endovascular techniques continued to be treatment options for basilar apex aneurysms (BAA). We conducted a systematic review to compare both treatment options in terms of both clinical and radiological outcomes.

METHODS

The PRISMA method was used to identify related articles. Data collected from each article and the two treatment approaches were compared in terms of favorable clinical outcome and complete/near complete occlusion rate. Subgroup analysis was done based on the size and the rupture status of BAA.

RESULTS

Fifty-nine (59) and 32 articles reported a measurable clinical and radiological outcome respectively. The weighted average favorable clinical outcome was significantly higher in the endovascular group (86.4% vs 79.6%, P<0.0001), while the weighted average complete/near complete occlusion rate was significantly higher in the surgical group (92.6% vs 83.8%, P<0.0001). In the subgroup analysis, the favorable clinical outcome remained significantly higher in the endovascular group for the ruptured, unruptured and giant/large BAA (P<0.001), but not in the small BAA subgroup (P=0.26). The occlusion rate remained significantly higher in the surgical group for all subgroups (P<0.001).

CONCLUSION

Treatment of BAA remains in a trade-off between favorable clinical outcome and complete or near-complete occlusion depending on the treatment modality selected. Careful selection of cases and judicial discussion between open surgical and endovascular team is warranted for treatment optimization.

Junctional dilatation of the basilar tip: A Normal anatomical variant with a benign natural history

PURPOSE

The intracranial arterial vasculature has numerous anatomical variants, which vary from largely benign to having remarkable clinical implications. The significance of a lesser known variant described as a junctional dilatation of the basilar artery tip has not yet been described in the literature.

METHODS

Retrospective query of radiology imaging reports was performed for vascular specific imaging of the head, which included descriptions related to the basilar junctional dilatation variant from 2005 to 2019 at a single institution. Imaging studies were individually scrutinized for true presence of the variant, and were assessed for any change in appearance over time. Primary data-points collected included length of time between imaging studies with stable appearance, intracranial aneurysm incidence, and frequency of hemorrhage associated with aneurysm rupture.

RESULTS

Fifty patients with multiple vascular exams were found to have the typical appearance of the basilar junctional dilatation variant. The variant was found to be stable over time in all patients, without interval expansion or basilar tip aneurysm development. Interval follow-up ranged from 1 to 156 months, with a mean follow-up length of 3.83 years, and total patient-years of follow-up of 192. No adverse neurological events were found which could be attributed to the basilar junctional dilatation variant.

CONCLUSION

Junctional dilatation of the basilar artery tip is a benign, normal variant of the posterior intracranial arterial circulation. It is important for both radiologists and clinicians to recognize its characteristic appearance and benign nature, as misdiagnosis may lead to unnecessary work-up, imaging, and/or treatment.

Acutely ruptured basilar artery bifurcation aneurysm, treated with simultaneous Cascade and Comaneci temporary-assisted coiling

Temporary stent-assisted coiling is an eligible approach for the treatment of acutely ruptured complex cerebral aneurysms. Improved material properties and industrial advances in braiding technology have led to the introduction of new stent-like devices to augment endovascular coil embolization. Such technology includes the Cascade and Comaneci neck-bridging devices. Both devices are manually controlled, non-occlusive and fully retrievable neck-bridging temporary implants. The braided nature and the ultra-thin wire, compliant structure of their bridging meshes helps maintain target vessel patency during coil embolization. In this video (video 1) we demonstrate the straightforward combination of two temporary neck-bridging devices for the embolization of an acutely ruptured aneurysm of the basilar artery. Technical success and complete embolization of the aneurysm were recorded at the final angiography. In this technical video we discuss the technical nuances of the Comaneci and Cascade coil embolization. neurintsurg;13/2/196/V1F1V1Video 1.

XRP44X Enhances the Cytotoxic Activity of Natural Killer Cells by Activating the c-JUN N-Terminal Kinase Signaling Pathway

Natural killer (NK) cells are innate lymphocytes that play an essential role in preventing cancer development by performing immune surveillance to eradicate abnormal cells. Since ex vivo expanded NK cells have cytotoxic activity against various cancers, including breast cancers, their clinical potential as immune-oncogenic therapeutics has been widely investigated. Here, we report that the pyrazole chemical XRP44X, an inhibitor of Ras/ERK activation of ELK3, stimulates NK-92MI cells to enhance cytotoxic activity against breast cancer cells. Under XRP44X stimulation, NK cells did not show notable apoptosis or impaired cell cycle progression. We demonstrated that XRP44X enhanced interferon gamma expression in NK-92MI cells. We also elucidated that potentiation of the cytotoxic activity of NK-92MI cells by XRP44X is induced by activation of the c-JUN N-terminal kinase (JNK) signaling pathway. Our data provide insight into the evaluation of XRP44X as an immune stimulant and that XRP44X is a potential candidate compound for the therapeutic development of NK cells.

Embolization of Basilar Tip Aneurysm via Ascending Cervical Artery

BACKGROUND

Unusual vascular anatomy can present treatment challenges as traditional approaches may be unfeasible.

CASE DESCRIPTION

In this case we describe a patient who presented with subarachnoid hemorrhage due to a ruptured basilar apex aneurysm, with an occluded left vertebral artery and severely stenotic right vertebral artery. Coil embolization was performed via catheterization of an ascending cervical artery, with a successful clinical and radiographic outcome.

CONCLUSIONS

This demonstrates novel use of an endovascular technique in the setting of multiple vascular pathologies.

Plea for an international Aneurysm Data Bank: description and perspectives

The disease resulting in the formation, growth, and rupture of intracranial aneurysms is complex. Research is accumulating evidence that the disease is driven by many different factors, some constant and others variable over time. Combinations of factors may induce specific biophysical reactions at different stages of the disease. A better understanding of the biophysical mechanisms responsible for the disease initiation and progression is essential to predict the natural history of the disease. More accurate predictions are mandatory to adequately balance risks between observation and intervention at the individual level as expected in the age of personalized medicine. Multidisciplinary exploration of the disease also opens an avenue to the discovery of possible preventive actions or medical treatments. Modern information technologies and data processing methods offer tools to address such complex challenges requiring 1) the collection of a high volume of information provided globally, 2) integration and harmonization of the information, and 3) management of data sharing with a broad spectrum of stakeholders.Over the last decade an infrastructure has been set up and is now made available to the academic community to support and promote exploration of intracranial disease, modeling, and clinical management simulation and monitoring.The background and purpose of the infrastructure is reviewed. The infrastructure data flow architecture is presented. The basic concepts of disease modeling that oriented the design of the core information model are explained. Disease phases, milestones, cases stratification group in each phase, key relevant factors, and outcomes are defined. Data processing and disease model visualization tools are presented. Most relevant contributions to the literature resulting from the exploitation of the infrastructure are reviewed, and future perspectives are discussed.

Assessment of the endoscopic endonasal approach to the basilar apex region for aneurysm clipping

OBJECTIVE

The expanded endoscopic endonasal approach (EEA) has shown promising results in treatment of midline skull base lesions. Several case reports exist on the utilization of the EEA for treatment of aneurysms. However, a comparison of this approach with the classic transcranial orbitozygomatic approach to the basilar apex (BAX) region is missing.The present study summarizes the results of a series of cadaveric surgical simulations for assessment of the EEA to the BAX region for aneurysm clipping and its comparison with the transcranial orbitozygomatic approach as one of the most common approaches used to treat BAX aneurysms.

METHODS

Fifteen cadaveric specimens underwent bilateral orbitozygomatic craniotomies as well as an EEA (first without a pituitary transposition [PT] and then with a PT) to expose the BAX. The following variables were measured, recorded, and compared between the orbitozygomatic approach and the EEA: 1) number of perforating arteries counted on bilateral posterior cerebral arteries (PCAs); 2) exposure and clipping lengths of the PCAs, superior cerebellar arteries (SCAs), and proximal basilar artery; and 3) surgical area of exposure in the BAX region.

RESULTS

Except for the proximal basilar artery exposure and clipping, the orbitozygomatic approach provided statistically significantly greater values for vascular exposure and control in the BAX region (i.e., exposure and clipping of ipsilateral and contralateral SCAs and PCAs). The EEA with PT was significantly better in exposing and clipping bilateral PCAs compared to EEA without a PT, but not in terms of other measured variables. The surgical area of exposure and PCA perforator counts were not significantly different between the 3 approaches. The EEA provided better exposure and control if the BAX was located ≥ 4 mm inferior to the dorsum sellae.

CONCLUSIONS

For BAX aneurysms located in the retrosellar area, PT is usually required to obtain improved exposure and control for the bilateral PCAs. However, the transcranial approach is generally superior to both endoscopic approaches for accessing the BAX region. Considering the superior exposure of the proximal basilar artery obtained with the EEA, it could be a viable option when surgical treatment is considered for a low-lying BAX or mid-basilar trunk aneurysms (≥ 4 mm inferior to dorsum sellae).

Treatment of Wide-Neck Intracranial Aneurysms with the Woven EndoBridge Device Associated with Stenting: A Single-Center Experience

BACKGROUND AND PURPOSE

The intrasaccular flow disruptor, the Woven EndoBridge device, is increasingly used for the treatment of wide-neck intracranial aneurysms. Due to unfavorable anatomy, additional stent placement is sometimes required to avoid Woven EndoBridge protrusion into bifurcation branches. We report our experience with the Woven EndoBridge associated with stent placement for the treatment of complex intracranial aneurysms.

MATERIALS AND METHODS

Patients with aneurysms treated with the Woven EndoBridge Single-Layer plus stent placement were evaluated retrospectively with prospectively maintained data. The technical feasibility, procedural complications, aneurysm occlusion, and clinical outcome were studied.

RESULTS

Seventeen patients and aneurysms treated with the Woven EndoBridge plus stent placement were included. The mean aneurysm size was 7 ± 3.1 mm. Aneurysm locations were the following: MCA (10 patients), anterior communicating artery (3 patients), basilar tip (3 patients), and posterior communicating artery (1 patient). Two lesions were ruptured and treated in the acute phase. The Woven EndoBridge and stent placement were successfully delivered in all cases. There were no permanent/major complications. Among the 2 patients with SAH, minor and completely reversible in-stent thrombosis occurred during treatment. An asymptomatic occlusion of the angular artery with a distal nonbifurcation aneurysm was discovered during the angiographic follow-up. Long-term (10.4 months) angiographic complete (Raymond-Roy I) and near-complete (Raymond-Roy II) occlusion was obtained in 11 (69%) and 2 (12.5%) aneurysms, respectively. The mean sizes of aneurysms showing Raymond-Roy I/Raymond-Roy II and Raymond-Roy III occlusion were 5.5 ± 2.1 mm and 10 ± 1 mm, respectively (P = .003). The mean fluoroscopy time was 35 ± 14 minutes.

CONCLUSIONS

Aneurysm embolization with the Woven EndoBridge device associated with stent placement appears technically feasible and effective for the treatment of lesions with unfavorable anatomy. In our study, this strategy was relatively safe with a low rate of relevant procedure-related adverse events.

Comparative Analysis of Orbitozygomatic and Subtemporal Approaches to the Basilar Apex: A Cadaveric Study

BACKGROUND

The subtemporal and orbitozygomatic approaches are the most commonly used surgical approaches for the treatment of basilar artery apex (BAX) aneurysms. Relative advantages and disadvantages are generally reported based on surgeons' experience. This study was performed to provide a detailed comparison between the subtemporal and orbitozygomatic approaches based on cadaveric dissection analysis for the treatment of BAX aneurysms.

METHODS

Subtemporal and orbitozygomatic approaches were performed on 5 cadaveric heads (10 sides), and the following variables were assessed and compared between the 2 approaches: 1) number of exposed perforators on P₁-posterior cerebral arteries (PCA); 2) lengths of exposure and clipping for bilateral PCA, superior cerebellar arteries (SCA), and basilar trunk; 3) surgical area of exposure; and 4) surgical freedom at the BAX.

RESULTS

Number of perforators exposed on P₁-PCA was not different between the subtemporal and orbitozygomatic approaches. Exposure and clipping of ipsilateral SCA and PCA were superior using the subtemporal approach, and better for contralateral SCA and PCA using the orbitozygomatic approach, all reaching statistical significance. The orbitozygomatic approach provided greater exposure and clipping length for the proximal basilar trunk. Although the surgical area of exposure was similar between the 2 approaches, the overall surgical freedom was greater in the orbitozygomatic approach.

CONCLUSIONS

The orbitozygomatic approach provides a greater number of surgical corridors to the BAX and is superior regarding multiple surgically relevant anatomic parameters. Importantly, control over the basilar trunk and over the contralateral SCA and PCA (blind spots) is superior with the orbitozygomatic approach.