Management Of Cerebral Aneurysms Research Articles

Numerical simulation of endovascular treatment options for cerebral aneurysms

AbstractPredicting the long‐term success of endovascular interventions in the clinical management of cerebral aneurysms requires detailed insight into the patient‐specific physiological conditions. In this work, we not only propose numerical representations of endovascular medical devices such as coils, flow diverters or Woven EndoBridge but also outline numerical models for the prediction of blood flow patterns in the aneurysm cavity right after a surgical intervention. Detailed knowledge about the postsurgical state then lays the basis to assess the chances of a stable occlusion of the aneurysm required for a long‐term treatment success. To this end, we propose mathematical and mechanical models of endovascular medical devices made out of thin metal wires. These can then be used for fully resolved flow simulations of the postsurgical blood flow, which in this work will be performed by means of a Lattice Boltzmann method applied to the incompressible Navier–Stokes equations and patient‐specific geometries. To probe the suitability of homogenized models, we also investigate poro‐elastic models to represent such medical devices. In particular, we examine the validity of this modeling approach for flow diverter placement across the opening of the aneurysm cavity. For both approaches, physiologically meaningful boundary conditions are provided from reduced‐order models of the vascular system. The present study demonstrates our capabilities to predict the postsurgical state and lays a solid foundation to tackle the prediction of thrombus formation and, thus, the aneurysm occlusion in a next step.

Preclinical Direct Endoluminal Assessment of Endothelialization After Flow Diversion With Microangioscopy

BACKGROUND Direct endoluminal imaging, such as with our previously described microangioscope, is an emerging adjunct in endovascular cerebral aneurysm management that enables clinicians to delineate between thrombi and visualize neoepithelialization after stent placement with high resolution. The present study sought to study flow diversion in vivo under direct endoluminal imaging, and to validate our findings with histopathology. METHODS In a rabbit model, we implanted each left common carotid artery with a shielded flow diverter (FD) (Medtronic Pipeline Vantage) and nonshielded FD (Medtronic Pipeline Flex) in the right common carotid artery. We studied 9 animals in 3 groups: (1) no periprocedural antiplatelet therapy, (2) aspirin 81 mg daily, and (3) aspirin 81 mg and clopidogrel 75 mg daily. FD thrombosis, stenosis, malapposition, and neoepithelialization were all evaluated by diagnostic cerebral angiography and microangioscopy after 30 days. Diagnostic cerebral angiography and angioscopic video were analyzed by independent evaluators and compared with histopathologic analysis. RESULTS In the aspirin and dual antiplatelet therapy groups, there were no significant observed differences in stent thrombosis, stenosis, malapposition, or neoepithelialization between the shielded and non‐shielded FD groups. There was significantly more thrombus formation in Group 1. Neointimal thickness as measured by the microangioscope was highly correlated with histology (r = 0.72; P = 0.016). Interrater agreement of microangioscope videos was highest for FD thrombosis and stenosis. CONCLUSION In‐stent thrombosis, stenosis, malapposition, and neopithelialization demonstrated no significant difference between shielded and non‐shielded FDs. Microangioscopy measurements for neointimal thickness were highly correlated with pathology and may be a helpful adjunct to diagnostic cerebral angiography in FD follow‐up.

High-frequency optical coherence tomography for endovascular management of cerebral aneurysms.

Endovascular management of intracranial aneurysms has become the mainstay of treatment in recent years; however, retreatment rates remain as high as 1 in 5. High-frequency optical coherence tomography (HF-OCT) is an emerging imaging modality for the assessment, treatment and follow-up of cerebral aneurysms. EMBASE and SCOPUS databases were searched for studies relating to the management of intracranial aneurysm with OCT. A combination of keywords were used including 'cerebral aneurysm', 'intracranial aneurysm', 'high-frequency optical coherence tomography', 'optical coherence tomography', and 'optical frequency domain imaging'. There were 23 papers included in this review. For the assessment of intracranial aneurysm, OCT was able to accurately assess aneurysm morphology as well as detailed analysis of arterial wall layers. During IA treatment, OCT was used to assess and troubleshoot stent placement to optimise successful isolation from the circulation. In the follow-up period, endothelial growth patterns were visualised by OCT imaging. OCT shows promise for the treatment of IAs at all stages of management. Due to the novel development of HF-OCT, there is limited longitudinal data in human studies. Further research in this area is required with a focus specifically on long-term treatment outcomes in humans.

158 Preclinical Direct Endoluminal Assessment of Endothelialization After Flow Diversion With Microangioscopy

INTRODUCTION: Endoluminal imaging (ELI) is an emerging adjunct in endovascular cerebral aneurysm management. Indirect ELI, as with optical coherence tomography, may be useful in detecting malapposition after flow diversion (FD). Direct ELI technologies, such as with our previous described microangioscope, have been shown to be able to delineate between different thrombi and visualize neoepithelialization after stent placement with high resolution. METHODS: In a rabbit model we implanted each left common carotid artery (CCA) with a shielded FD (Medtronic Pipeline Vantage) and non-shielded FD (Medtronic Pipeline Flex) in the right CCA. We studied 9 animals in 3 groups: 1) no periprocedural antiplatelet therapy, 2) aspirin 81 mg daily, 3) aspirin 81 mg and clopidogrel 75 mg daily. FD thrombosis, stenosis, malapposition, and neoepithelialization were all evaluated by diagnostic cerebral angiography (DSA) and microangioscopy after 30 days. DSA and angioscopic video were analyzed by independent evaluators and compared with histopathologic analysis. RESULTS: In the aspirin and DAPT groups, there were no significant observed differences in stent thrombosis, stenosis, malapposition, or neoepithelialization between the shielded and non-shielded FDs in each rabbit as measured by histologic analysis. There was significantly more thrombus formation in Group 1. Neointimal thickness as measured by the microangioscope was highly correlated with histology (r = 0.72, p = 0.016). Inter-rater agreement of microangioscope videos was highest for FD thrombosis and stenosis. CONCLUSIONS: There were no significant differences between in-stent thrombosis, stenosis, malapposition, or neopithelialization between shielded and non-shielded FDs. Microangioscopy measurements for neointimal thickness were highly correlated with pathology, and thus may be a helpful adjunct to DSA in FD follow-up.

Optimizing resources: financial evaluation of flow diverters versus stent assisted coiling in large and giant cerebral aneurysm management in Brazil public health system

BackgroundCerebral aneurysms, especially large and giant aneurysms, pose challenges in neurointerventional surgery. Treatment choices involve clinical presentation, aneurysm details, and global resource variations. Neurointerventional methods, while innovative, may be cost...

Evaluating Efficacy and Complications of Contour Intrasaccular Device in Cerebral Aneurysm Management: A Multicenter Analysis

IntroductionIntrasaccular devices provide a method for treating complex aneurysms without leaving metallic materials in the parent artery. Compared to other well-studied devices in neurointervention, the Contour device is relatively new as an intrasaccular flow diverter. This study examines its use in cases of incidental aneurysms and its application in the acute treatment of ruptured aneurysms. Additionally, it covers potential complications that may arise and methods for prevention. MethodsWe conducted a retrospective analysis of 25 patients who underwent treatment with the Contour device at three hospital centers. We collected data related to age, gender, baseline modified Rankin Scale (mRS), personal habits, medical history, procedure details, and angiographic results according to the WEB occlusion scale (WOS). ResultsA total of 15 patients (65.5%) achieved a satisfactory angiographic result (grade 0-0’) one year after embolization. Contrast stagnation was observed in 14 patients (58.3%). Intraprocedural complications, such as device displacement, were documented in 3 patients (12%), while 2 patients (8%) had aggregates attached to the device. Regarding late complications, 5 patients (20%) experienced device displacement, and 1 patient had a minor stroke (4%). Retreatment was necessary for 3 patients (12%), involving a flow diverter, stenting, and coiling. Discussion and ConclusionIn summary, the Contour device offers a viable option for treating complex aneurysms. While initial results are promising, it's crucial to acknowledge a learning curve to minimize complications and achieve satisfactory angiographic results without the need for additional treatments.

Gut microbiome in intracranial aneurysm growth, subarachnoid hemorrhage, and cerebral vasospasm: a systematic review with a narrative synthesis.

Intracranial aneurysms (IA) are the most common cerebral vascular pathologies. Their rupture leads to the most dangerous subtype of stroke-aneurysmal subarachnoid hemorrhage (aSAH), which may be followed by cerebral vasospasm and ischemic sequelae. Recently, an imbalance within the intestinal microbiota, referred to as dysbiosis, was suggested to play a role in the formation, progression, and rupture of IA. As no systematic review on this topic exists, considering the significance of this matter and a lack of effective prophylaxis against IA or cerebral vasospasm, we aim to sum up the current knowledge regarding their associations with intestinal microbiome, identify the gaps, and determine future prospects. Scientific databases were systematically and independently searched by two authors from inception to 1st May 2023 for original articles regarding the role of intestinal microbiota in intracranial aneurysmal growth, aSAH occurrence, as well as in cerebral vasospasm following aSAH. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) checklist was followed in an abstraction process. The STROBE tool was applied to assess the risk of bias. This research was funded by the National Science Centre, Poland (grant number 2021/41/N/NZ2/00844). Of 302 records, four studies were included that fully met eligibility criteria. Studies reported (1) that the relative abundance of Hungatella hathewayi is a protective factor against aneurysm growth and rupture, resulting from the reduced inflammation and extracellular matrix remodeling in the cerebral arterial wall and from reduced metalloproteinase-mediated degradation of smooth muscle cells in cerebral vessels. (2) Relative abundance of Campylobacter ureolyticus is associated with aSAH. (3) No article has evaluated microbiota in relation to cerebral vasospasm following aSAH although there is an ongoing study. We concluded that intestinal microbiota might be a potential target for diagnostic and therapeutic tools to improve the management of cerebral aneurysms. However, more studies of prospective design are needed.

Coil embolization and recurrence of ruptured aneurysm originating from hyperplastic anterior choroidal artery.

Hyperplastic anterior choroidal artery (AchA) is an extremely rare congenital vascular variant that can be mistaken for other cerebral arteries. This case report presents a 38-year-old man who presented with a severe sudden-onset headache and was diagnosed with a ruptured aneurysm originating from a hyperplastic AchA. The aneurysm was successfully treated with coil embolization, but recurrence was detected after eight months, leading to additional surgical intervention. The discussion highlights the classification of hyperplastic AchA and emphasizes the importance of recognizing this anatomical variant to avoid complications during treatment. This case report underscores the need for awareness and understanding of hyperplastic AchA in the management of cerebral aneurysms.

A novel parameter for the prediction of rupture risk of cerebral aneurysms based on morphology.

Neurosurgeons often encounter dilemmas in the clinical management of cerebral aneurysms owing to an uncertainty of their rupture status and rupture risk. This study evaluates the influence of natural frequency of an aneurysm, as a novel morphological parameter to understand and analyze rupture status and risk prediction. In this work, we employ the natural frequency of 20 idealized and 50 patient specific aneurysms. The natural frequency of patient specific aneurysms is then compared against their rupture status. A strong correlation was observed between various morphological indicators and natural frequency for ideal and patient specific geometries. A statistical analysis with both Mann Whitney U test and T-test for rupture status against natural frequency has given a p-value less than 0.01 indicating a strong correlation between them. The correlation of morphological parameters with natural frequency from Pearson correlation coefficient and T-test suggests a holistic reflection of their effects on the natural frequency of an aneurysm. Thus, natural frequency could be a good indicator to discern the rupture potential of an aneurysm. The correlation between rupture status and natural frequency makes it a novel parameter that can differentiate between ruptured and unruptured patient specific aneurysms.

Clinical Management of Cerebral Aneurysms

A number of people die every year because of aneurysms. Wide range of researches have been conducted into aneurysms, particularly for brain aneurysms. Due to the serious consequences of intracranial haemorrhage, there have been many new treatments including medication and surgical approaches developed in recent years, but at the same time there is still much room for technological improvement. As research has progressed, researchers have discovered that aneurysms are inextricably linked to inflammation and have proposed a number of medications to treat this condition. However, medication can only control aneurysms to a limited extent and is usually used as an adjunct to surgical treatment. This article summarizes the treatment of different aneurysms, as well as the prospect of surgical intervention and its future perspectives.

Particular management strategy for intraprocedural coil migration during endovascular treatment of intracranial aneurysm

Migration of coils represents one of the most challenging complications of endovascular management of cerebral aneurysms with a potentially catastrophic result. In this article, we present the successful management of a coil migration during the endovascular occlusion of an anterior communicating artery aneurysm. A stent fixation technique was used with good vascular repermeabilisation. The reported frequency, risk factors and management strategies are also discussed.

Use of Second Window ICG in spinal cord biopsy of a mildly contrast-enhancing lesion: Technical note and review of the literature

IntroductionIndocyanine green (ICG) is commonly used to visualize cerebral vasculature, particularly in the management of cerebral aneurysms. There have also been attempts to use ICG for visualization of tumors. Injection of ICG followed by immediate fluorescence microscopy is limited by the short time window for imaging and administration and restricted depth of imaging. Second Window Indocyanine Green (SWIG) addresses these issues by allowing for longer contrast times and the imaging of deeper regions of brain tissue. Biopsy of spinal cord lesions is often difficult for a variety of reasons, including the delicate nature of the tissue and differentiating normal from lesional tissue visually, especially in lesions with heterogeneous enhancement. MethodsIn this case report, we describe the use of second window ICG to facilitate the visualization of a spinal cord lesion and subsequent biopsy of the lesion. ResultsThis patient is a 24-year-old female who had recurrence of a suprasellar germinoma. An MRI of the rest of the neuraxis was performed to assess for the presence of drop metastases. The spinal cord from C2-5 was expanded with areas of patchy enhancement; however, this lesion was asymptomatic. The patient's oncologist requested a biopsy of this lesion to help direct subsequent care of her recurrent germinoma. The day before surgery, the patient had an intravenous injection of ICG dye. She then underwent a C3-5 laminectomy for biopsy of her cervical intramedullary lesion. After opening of the dura, no visible abnormality of the spinal cord could be identified. A Stryker endoscope showed an area of ICG uptake in the cord at approximately the C3-4 level. A midline myelotomy was centered over the ICG demarcated area and several samples were taken for pathology. Final biopsy results determined the lesion to be spinal cord parenchyma with perivascular and intraparenchymal lymphocytes – not consistent with spinal cord tumor or germinoma. ConclusionSecond Window ICG is effective in visualizing otherwise visually unremarkable spinal cord lesions. This technology can facilitate biopsy of these lesions and possibly their surgical resection.

P120 The burden of the management of cerebral aneurysms in Africa: a scoping review

IntroductionIn Africa, the epidemiology, management, and prognosis of cerebral aneurysms remain poorly understood. Cerebral aneurysms are still highly underdiagnosed and inadequately treated in Africa due to a lack of vascular neurosurgeons and infrastructure. In this review we mapped the burden and management of intracerebral aneurysm in Africa.MethodsA full systematic search on articles published in Africa on brain aneurysms was performed in PubMed, African Journals Online, Google Scholar, WHO Global Health Library and LILACS with no language restrictions. The search results were merged, uploaded into Rayyan software, (FDT, USK, IN, NDAB) independently based on the pre-defined inclusion and exclusion criteria. The full text of the remaining articles were then retrieved and screened by three reviewers independently (FDT, USK, NDAB). Conflicts were resolved by mutual agreement. From all included documents, we extracted information regarding study design, socio-demographic characteristics, clinical findings, type of treatment and outcome results.ResultsWe included 28 articles in our full text retrieval. These studies totaled 1181 patients managed for cerebral aneurysm in Africa. Half (50.0%; n = 14) of all studies had been published in the past 5 years and nearly half (46.4%; n = 13) of these studies were conducted in two countries: eight in Morocco and five in South Africa, we didn’t found any publication on cerebral aneurysm for nearly 80% of African countries. Also, there was a female predominance among cerebral aneurysm study participants (62.5%), and the mean time from diagnosis to surgery was 12.1 days. Cerebral aneurysms were most often located in the internal carotid artery (29.6%) and anterior cerebral artery (23.2%). Microneurosurgery (67%) was the most widely used option in these studies ahead of coiling (7.9%). Patient outcomes were judged favorable in 64.2% of cases, and the mortality rate following surgical (open vascular and endovascular) intervention was 19.4%.ConclusionThe management of intracerebral aneurysms remains suboptimal in Africa. There are few peer-reviewed reports of aneurysm practice.

Artificial Neural Network for Predicting the Safe Temporary Artery Occlusion Time in Intracranial Aneurysmal Surgery.

Background. Temporary artery clipping facilitates safe cerebral aneurysm management, besides a risk for cerebral ischemia. We developed an artificial neural network (ANN) to predict the safe clipping time of temporary artery occlusion (TAO) during intracranial aneurysm surgery. Method. We devised a three-layer model to predict the safe clipping time for TAO. We considered age, the diameter of the right and left middle cerebral arteries (MCAs), the diameter of the right and left A1 segment of anterior cerebral arteries (ACAs), the diameter of the anterior communicating artery, mean velocity of flow at the right and left MCAs, and the mean velocity of flow at the right and left ACAs, as well as the Fisher grading scale of brain CT scans as the input values for the model. Results. This study included 125 patients: 105 patients from a retrospective cohort for training the model and 20 patients from a prospective cohort for validating the model. The output of the neural network yielded up to 960 s overall safe clipping time for TAO. The input values with the greatest impact on safe TAO were mean velocity of blood at left MCA and left ACA, and Fisher grading scale of brain CT scan. Conclusion. This study presents an axillary framework to improve the accuracy of the estimated safe clipping time interval of temporary artery occlusion in intracranial aneurysm surgery.

Can biomechanical analysis shed some light on aneurysmal pathophysiology? Preliminary study on ex vivo cerebral arterial walls

BackgroundThe pathophysiology of cerebral aneurysm is complex and poorly understood, and it can have the most catastrophic clinical presentation. Flow dynamics is a key player in the initiation and progression of aneurysm. Better understanding the interaction between hemodynamic loading and biomechanical wall responses can help to add the missing piece on aneurysmal pathophysiology. In this laboratory study we aimed to analyze the effect of the application of a mechanical force to cerebral arterial walls. MethodsDisplacement control tests were performed on five porcine cerebral arteries. The test machine was the T150 Nanotensile. The stiffness variation with the increment of the strain level is modeled as the outcome of an isotropic hyperelastic material model. FindingsThrough the application of an axial force we obtained Stress/Strain curves that showed a marked isotropic hyperelastic behavior, characterized by an increasing of stiffness with the level of strain. This behavior of the cerebral arterial wall is different from the well-established behavior of other arterial vessel (as the aortic vessel) characterized by a marked anisotropic behavior. Additionally, the data scattering observed for higher values of the applied stress are related to different individual packing of collagen fibers that represent the load-bearing mechanics at higher level of the strain. InterpretationThe data obtained by test in this paper represent a first step in our ongoing research about the mechanics of multi-axial loads on cerebral arterial walls, and in producing more comprehensive patient-specific calculations for potential applications on cerebral aneurysm management.

A Cadaveric Anatomical Study on Anterior Communicating Artery Aneurysm Surgery by Extended Endoscopic Endonasal Approach.

Background:The use of minimally invasive approaches in the management of cerebral aneurysms continues to evolve and a purely endoscopic endonasal approach (EEA) for cerebral aneurysm has its own advantages. The purpose of the present study is to perform a detailed anatomical dissection study to test the usefulness of the extended EEAs for selected anterior communicating artery (ACoA) aneurysm.Materials and Methods:Nine human cadaveric heads were used for this study, and all dissections were performed through the endonasal corridor. Endoscopic endonasal surgical dissections were carried out, and surgery was simulated in all specimens to reach the ACoA region. The ACoA complex, its neural and osseous relations, degree of vascular exposure, and the ability to perform clip placement were observed and analyzed.Results:The transplanum and transtuberculum approaches exposed the A1 and A2 segments of the anterior cerebral artery and the ACoA in all specimens. This route allowed clip ligation of the distal A1 branches, ACoA and proximal A2 branches to the level of the pericallosal segment. Proximal and distal control was most readily achievable at the level of the ACoA complex.Conclusion:The present cadaveric study on nine specimens with bilateral dissection has demonstrated that the endonasal transplanum transtuberculum approach to the ACoA region provides excellent visualization of the vasculature. When selected prudently, such lesions may be favorable targets for an extended endoscopic endonasal (EEA) in comparison to transcranial approaches that may provide a suboptimal exposure.

Letter to the Editor Regarding “Large Craniotomy Increases the Risk of Minor Perioperative Complications in Revascularization Surgery for Moyamoya Disease”

Cerebral aneurysms are rare in the pediatric population, making a definitive treatment algorithm difficult. Microsurgical clipping is the first choice for treatment but is not always feasible, while high recurrence rates and radiation exposure make endovascular options less favorable. Extracranial-intracranial (EC-IC) bypass, though not commonly performed in the pediatric aneurysm population, has been reported in a small number of studies to be both safe and effective for the management of cerebral aneurysms. The authors present the case of a child with a distal middle cerebral artery (MCA) aneurysm in eloquent territory, successfully treated with a superficial temporal artery (STA) to MCA bypass and trapping. A review of the current literature on pediatric EC-IC bypass in the treatment of intracranial aneurysms is presented.

Management of Anterior Cerebral Circulation Aneurysms by Endovascular Coiling

Background: Endovascular management of cerebral aneurysms is relatively a new modality of management in Egypt. So, studies are needed to evaluate efficacy, safety, and outcome; especially with this rapid evolution in both materials and equipment. Aim of the work: To asses safety, efficacy, and outcome of our case series with cerebral aneurysm managed by endovascular coiling.Patients and Methods: Here we documented the clinical, treatment, and outcome variables of cerebral aneurysm case series treated by endovascular coiling between May 2018 and December 2019 in a single center in Egypt.Results: In 30 patients, 34 aneurysms were found, 31 aneurysms [91.1%] were treated by coiling, and only 3 aneurysms [2 cases] [8.9%] failed to be treated by coiling. Total occlusion was achieved in 25 aneurysms [80.6%]. Neck remnants were present in 6 aneurysms [19.4%]. Regarding functional outcome, 26 patients had good outcome and 2 patients had poor outcome.Conclusion: Endovascular coiling is safe and effective method for management of cerebral aneurysm and should considered as the first choice in management.

Anaesthetic Management of Cerebral Aneurysm Surgery

Management of cerebral aneurysm is always a challenge for a neurosurgeon and anaesthesiologist. Proper knowledge, experience, timely intervention and goal directed therapy will definitely save a lot of lives. The leading causes of death and disability were, in descending order, vasospasm, the direct effects of the initial bleed (massive subarachnoid, subdural, or intracerebral hematoma, permanent ischemic effects of increased intracranial pressure, rebleeding, and surgical complications. This article revises the anaesthetic challenges during managing the cerebral aneusysms.

Combined Endovascular and Microsurgical Hybrid Management of Cerebral Aneurysms: The Preliminary Fujita Experience.

Introduction:A subgroup of complex aneurysms demands multimodal treatment by microscopic and endovascular means. Partial obliteration or remnant postprocedure demands to go further to the other modality.Materials and Methods:All patients between July 2016 and January 2017 who had to undergo multimodality measures for complete obliteration of the aneurysms were included in the study. The patients who had either undergone clipping or coiling for their aneurysms, but with incomplete obliteration of the aneurysm, were also included in the study.Results:Between July 2016 and January 2017, a total of three patients had to undergo coiling after clipping of the aneurysm for complete obliteration. Two patients had to go for clipping following coiling. All five patients had complete obliteration of the aneurysm sac.Conclusion:Both microscopic and endovascular means are complementary measures instead of competing procedures. It is important to realize the technical difficulties when surgical therapy follows initial endovascular treatment. Similarly, coiling a previously clipped aneurysm can be difficult, if the clip obscures normal working projections.