Saccular Aneurysm Research Articles

Adenosine-induced cardiac standstill in intracranial aneurysm surgery: A case report

Surgical clipping of complex intracranial aneurysms can pose intraoperative challenges due to difficulty in anatomic exposure and uncontrolled intraoperative rupture, leading to significant morbidities or mortalities. This report presents a case of a 61-year-old Asian male with an unruptured saccular basilar tip aneurysm and an unruptured right middle cerebral artery aneurysm. The patient underwent a left temporal craniotomy and clipping of an unruptured basilar tip aneurysm, successfully achieved through adenosine-induced cardiac standstill. This technique reduces perfusion pressure and decreases the turgor of the aneurysm, thereby facilitating clip ligation. Our experience demonstrated that thorough, careful patient selection, optimal anesthetic management, and proper communication between neurosurgeon and anesthesiologist are important for achieving successful surgical outcomes.

Feasibility of single antiplatelet therapy after stent assisted coiling for ruptured intracranial aneurysms.

We retrospectively analyzed clinical data to evaluate the safety and efficacy of single antiplatelet therapy (SAPT) after stent-assisted coil embolization (SAC) for ruptured cerebral aneurysms. In total, 176 stent-assisted coil embolization procedures were investigated. Among them, 77 ruptured and 99 unruptured aneurysms were grouped and compared respectively. In the ruptured group, only SAPT (aspirin) was administered after the procedure. Meanwhile, in the unruptured group, dual antiplatelet therapy (DAPT) (aspirin and clopidogrel) was administered before and after the procedure following standard guidelines. We compared both groups in regards to thromboembolic complications by analyzing post procedural diffusion-weighted images (DWI), hyperacute thrombosis during the procedure, and post-procedural symptoms. The single antiplatelet therapy ruptured intracranial aneurysm (SAPT-RIA) group had 77 saccular aneurysms (62 ICA, 3 MCA, 4 ACA, 8 posterior circulation) with a mean diameter of 8.07 mm. The dual antiplatelet therapy unruptured intracranial aneurysm (DAPT-UIA) group had 99 aneurysms (81 ICA, 5 MCA, 3 ACA, 10 posterior circulation) with a mean diameter of 6.32 mm. DWI positivity rates were similar between groups, but hyperacute thrombosis was higher in the SAPT-RIA group (10.4%) compared to none in the DAPT-UIA group. Each group had one symptomatic complication. SAPT could be a viable option for the peri-procedural management of SAC in acutely ruptured cases.

Comprehensive Management of Thrombosed Lower Extremity Venous Aneurysms: A Single-Center Retrospective Analysis and Insights Into Clinical Strategies.

Venous aneurysms are rare vascular abnormalities associated with venous thromboembolism. In this study, we presented our experience in managing thrombosed lower extremity venous aneurysms and evaluate the impact of vitamin D deficiency and genetic thrombophilic risk factors on patient management and outcomes. A single-center retrospective observational analysis was conducted on ten patients with thrombosed lower limb venous aneurysms who underwent surgical procedures at our hospital from July 2014 to February 2023. Collected data included venous duplex ultrasonographic imaging and laboratory tests including genetic thrombophilic risk factors and assessments of vitamin D levels. There were 5 males and 5 females. The mean age was 46.6 ± 12.1years. The aneurysms were located in the popliteal vein in three patients, the great saphenous vein in six, and the small saphenous vein in one. Venous duplex imaging revealed saccular aneurysms in eight patients and fusiform aneurysms in two, with a mean diameter of 37.2 ± 10.6mm, ranging from 23 to 52mm. Laboratory tests indicated vitamin D deficiency in all of the patients, and genetic thrombophilic risk factors were identified in two cases. Surgical interventions consisted of tangential excision with lateral venorrhaphy in three patients and total excision and ligation in seven patients. The postoperative period was favorable for all patients. Surgical treatment of thrombosed venous aneurysms in the lower extremities is essential to prevent complications such as thromboembolism. A comprehensive approach, including knowledge of genetic risk factors and vitamin D levels, may improve patient outcomes.

Transcirculation Approaches to Endovascular Flow Diversion of Intracranial Aneurysms: A Systematic Review With Technical Considerations.

Flow diversion (FD) of intracranial aneurysms (IAs) is an increasingly used and efficacious treatment modality. Transcirculation approaches, or approaches that cross the contralateral or anteroposterior arterial supply before reaching a target vessel, have been used to treat cerebrovascular pathologies when traditional approaches are unsuitable or require intraoperative complication management. This study sought to review IAs treated with FD using a transcirculation approach to determine the technique's safety and efficacy. A systematic review of the PubMed, Scopus, Web of Science, and Embase databases was completed per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies were included if they described transcirculation approaches in adult patients with IAs undergoing FD. Outcomes of interest included intraoperative complications and aneurysm occlusion rates. Twelve studies with 19 patients (N = 19, mean age = 54.1 y, 89.5% female) were identified. Wide-necked (N = 5, 26.3%) and saccular (N = 5, 26.3%) aneurysms were most represented, while 57.9% (N = 11) of aneurysms were unruptured and 15.8% (N = 3) of aneurysms were ruptured. The mean aneurysm sac and neck size were 16.9 mm and 11.9 mm, respectively. The most commonly deployed flow diverter was the Pipeline Embolization Device (N = 14, 73.9%). Successful FD (complete occlusion and/or good wall apposition) was recorded in 84.6% of qualifying patients with follow-up data, while 2 patients (15.4%) developed an intraoperative carotid-cavernous fistula. Transcirculation approaches to FD offer neurointerventionalists a safe and efficacious method for device deployment, rescue scenarios, and challenging anatomy. Prospective studies may determine the most appropriate indications for transcirculation approaches to FD, while novel, lower profile devices may improve its technical feasibility and safety.

Cardiac Arrest during Temporary Clipping for Ruptured Internal Carotid Artery Aneurysm: A Case Report

Abstract Objectives Mechanical stimulation of the trigeminal nerve during craniofacial, skull base, or dental surgeries may cause bradycardia, hypotension, or cardiac arrest. This phenomenon is called trigeminal cardiac reflex (TCR). We encountered a rare case of a patient who experienced sinus arrest due to temporary clipping of the intracranial carotid artery during the clipping of a ruptured aneurysm. We discuss possible reasons for the occurrence of TCR in this case. Materials and Methods A man in his 30s with no medical history presented with a sudden-onset headache. Computed tomography revealed a subarachnoid hemorrhage in the basal cistern and left Sylvian fissure. Angiography revealed a saccular aneurysm of the left internal carotid-anterior choroidal artery. A left frontotemporal craniotomy and dural incision were performed, followed by a trans-Sylvian approach. Cardiac arrest occurred twice during the temporary clipping of the intracranial carotid artery. After surgery, we performed a cardiac ultrasound echo and a 1-week Holter electrocardiogram. Neither showed abnormalities. No arrhythmia or cardiac events were observed over a one and half-year follow-up period. Results The cardiac arrest might have been triggered by the stimulation of the trigeminal nerve in the internal carotid artery. The repeated and anatomical features of this case suggest that TCR triggered cardiac arrest. Conclusion The high probability that cardiac arrest was induced by trigeminal nerve stimulation should be considered during the temporary clipping of the internal carotid artery. However, the predisposing factors and exact underlying mechanisms for these arrhythmias remain unknown and require further investigation.

Comparative Efficacy and Safety of Self-Expandable vs. Balloon-Expandable Stent Grafts in Visceral Artery Aneurysm Management.

This study assesses the efficacy and safety of self-expandable (SE) versus balloon-expandable (BE) stent grafts for managing visceral artery aneurysms (VAAs), focusing on procedural success and complication rates. We conducted a retrospective analysis of VAA patients treated at our institution from April 2006 to September 2021. The study reviewed patient demographics, aneurysm characteristics, treatment details, and outcomes, including endoleaks. Among the 23 patients analyzed, splenic artery aneurysms represented 44% of cases. Fifteen patients were treated with balloon-expandable stent grafts (BE SGs), and eight patients were treated with self-expandable stent grafts (SE SGs). For saccular aneurysms, the average neck size was 10.10 ± 8.70 mm in the BE group versus 18.50 ± 3.40 mm in the SE group (p = 0.23), with an average sac size of 20.10 ± 18.9 mm in the BE group versus 15.60 ± 12.7 mm in the SE group (p = 0.16). The average sac-to-neck ratio was 1.69 ± 2.23 in the BE group versus 1.38 ± 0.33 in the SE group (p = 0.63). The BE group exhibited a significantly higher endoleak rate (60%) compared to the SE group (12.5%; p = 0.03). While further investigation is needed to fully assess the outcomes of stent graft treatment for VAAs, initial data show a significantly higher endoleak rate with BE SGs compared to SE SGs. The SE SGs may offer better outcomes due to their superior ability to conform to tortuous and mobile visceral arteries.

Effects of hematocrit and non-Newtonian blood rheology on pulsatile wall shear stress distributions in vascular anomalies: A multiple relaxation time lattice Boltzmann approach

In the present study, we investigate the flow dynamics of non-Newtonian blood, focusing on the distribution of wall shear stress (WSS) and hematocrit levels, which is the volume percentage of red blood cells in whole blood. We analyze these factors under pulsatile conditions, in vascular anomalies such as stent channels and intracranial aneurysms. To achieve this, a three-dimensional computational approach based on the lattice Boltzmann method (LBM) with a multiple relaxation time (MRT) collision operator is employed. To represent the blood's shear-thinning properties, we developed a constitutive model inspired by the Carreau–Yasuda model. This model considers the variability in blood viscosity with shear rate correlated with hematocrit levels based on experimental data documented in the literature. The accuracy of the employed MRT-LBM is demonstrated by the consistency of results with analytical solutions for steady state and experimental data for pulsatile WSS distributions in non-Newtonian and Newtonian fluids. Results indicate that, in areas narrowed by stenosis or expanded by aneurysms, hematocrit levels affect flow dynamics. Higher hematocrit levels intensify pulsatile flow through stenotic regions, increasing WSS cyclic variations. We derived a density distribution function to demonstrate how shear rates vary in vascular anomalies, revealing blood viscosity changes and non-Newtonian properties. These properties complicate flow patterns, resulting in non-linear WSS distributions, which are essential for understanding endothelial cell reactions and disease pathways. Pulsatile blood flow and altered rheological properties due to increased hematocrit affect saccular aneurysm fluid dynamics over time and space, causing vorticities to change shape, size, and intensity.

A rare presentation of saccular aneurysm at junction of middle carotid artery and internal carotid artery mimicking the normal tension glaucoma

Acquired (pathologic) excavation of the optic cup is not always due to glaucoma. Ophthalmological signs of pathological disc cupping have been recognised in patients with normal intraocular pressures and with optic atrophy of various causes including ischaemic and compressive optic neuropathy, optic neuritis and trauma. Intracranial lesions have been reported to mimic the clinical presentation of glaucomatous optic disc changes and have also resulted in misdiagnosis. Optic atrophy caused by intracranial lesions shows pallor more than cupping. The macular nasal–temporal ratio compares the nasal and temporal thickness of the macular ganglion cell and inner plexiform layer and can be used to differentiate between compressive and non-compressive lesions as depicted in this case. This case report also suggests the importance of different imaging modalities in diagnosing compressive lesions and differentiating them from similar conditions.

A combined endovascular and open repair of innominate artery bifurcation pseudoaneurysm: a case report

BackgroundInnominate artery aneurysms (IAAs) are rare and may result in rupture, distal arterial embolization, or local compression without timely treatment. Rupture is the most dangerous of these complications. This article reports a case of innominate artery bifurcation pseudoaneurysm.Case presentationThe patient was a 45-year-old man who was admitted to the emergency department due to chest discomfort. The computed tomographic angiography (CTA) imaging indicated the presence of a 3.6*2.4 cm saccular aneurysm in the bifurcation of the innominate artery, involving both the right proximal subclavian and common carotid arteries. The patient’s vital signs were normal, there was equal blood pressure in the upper arms and no neurological dysfunction was observed. Gadolinium-enhanced magnetic resonance angiography indicated that the circle of Willis was intact. The treatment involved open surgery combined with endovascular therapy. The external carotid artery was first transposed to the right subclavian artery (RSA) and an 8-mm woven Dacron graft was inserted in the middle. The covered stent graft was then placed in the proximal part of the innominate artery to close the entrance of the aneurysm. Lastly, an occluder was implanted at the origin of the RSA. There were no perioperative or postoperative complications. At 1-year follow-up, no aneurysm was observed on CTA and the right vertebral artery was patent.ConclusionsThis study indicated that the combined use of endovascular therapy and open repair surgery is an effective strategy to treat innominate artery bifurcation pseudoaneurysm.

Development of an Injectable, ECM-Derivative Embolic for the Treatment of Cerebral Saccular Aneurysms.

Cerebral aneurysms are a source of neurological morbidity and mortality, most often as a result of rupture. The most common approach for treating aneurysms involves endovascular embolization using nonbiodegradable medical devices, such as platinum coils. However, the need for retreatment due to the recanalization of coil-treated aneurysms highlights the importance of exploring alternative solutions. In this study, we propose an injectable extracellular matrix-derived embolic formed in situ by Michael addition of gelatin-thiol (Gel-SH) and hyaluronic acid vinyl sulfone (HA-VS) that may be delivered with a therapeutic agent (here, RADA-SP) to fill and remodel aneurysmal tissue without leaving behind permanent foreign bodies. The injectable embolic material demonstrated rapid gelation under physiological conditions, forming a highly porous structure and allowing for cellular infiltration. The injectable embolic exhibited thrombogenic behavior in vitro that was comparable to that of alginate injectables. Furthermore, in vivo studies in a murine carotid aneurysm model demonstrated the successful embolization of a saccular aneurysm and extensive cellular infiltration both with and without RADA-SP at 3 weeks, with some evidence of increased vascular or fibrosis markers with RADA-SP incorporation. The results indicate that the developed embolic has inherent potential for acutely filling cerebrovascular aneurysms and encouraging the cellular infiltration that would be necessary for stable, chronic remodeling.

L-Wnk1 Deletion in Smooth Muscle Cells Causes Aortitis and Inflammatory Shift.

The long isoform of the Wnk1 (with-no-lysine [K] kinase 1) is a ubiquitous serine/threonine kinase, but its role in vascular smooth muscle cells (VSMCs) pathophysiology remains unknown. AngII (angiotensin II) was infused in Apoe-/- to induce experimental aortic aneurysm. Mice carrying an Sm22-Cre allele were cross-bred with mice carrying a floxed Wnk1 allele to specifically investigate the functional role of Wnk1 in VSMCs. Single-cell RNA-sequencing of the aneurysmal abdominal aorta from AngII-infused Apoe-/- mice revealed that VSMCs that did not express Wnk1 showed lower expression of contractile phenotype markers and increased inflammatory activity. Interestingly, WNK1 gene expression in VSMCs was decreased in human abdominal aortic aneurysm. Wnk1-deficient VSMCs lost their contractile function and exhibited a proinflammatory phenotype, characterized by the production of matrix metalloproteases, as well as cytokines and chemokines, which contributed to local accumulation of inflammatory macrophages, Ly6Chi monocytes, and γδ T cells. Sm22Cre+Wnk1lox/lox mice spontaneously developed aortitis in the infrarenal abdominal aorta, which extended to the thoracic area over time without any negative effect on long-term survival. AngII infusion in Sm22Cre+Wnk1lox/lox mice aggravated the aortic disease, with the formation of lethal abdominal aortic aneurysms. Pharmacological blockade of γδ T-cell recruitment using neutralizing anti-CXCL9 (anti-CXC motif chemokine ligand 9) antibody treatment, or of monocyte/macrophage using Ki20227, a selective inhibitor of CSF1 receptor, attenuated aortitis. Wnk1 deletion in VSMCs led to aortic wall remodeling with destruction of elastin layers, increased collagen content, and enhanced local TGF-β (transforming growth factor-beta) 1 expression. Finally, in vivo TGF-β blockade using neutralizing anti-TGF-β antibody promoted saccular aneurysm formation and aorta rupture in Sm22 Cre+ Wnk1lox/lox mice but not in control animals. Wnk1 is a key regulator of VSMC function. Wnk1 deletion promotes VSMC phenotype switch toward a pathogenic proinflammatory phenotype, orchestrating deleterious vascular remodeling and spontaneous severe aortitis in mice.

Exoscopic Clipping of a Ruptured Posterior Communicating Artery Aneurysm Through a Minipterional Approach: 2-Dimensional Operative Video

Posterior communicating artery (PCoA) aneurysms represent approximately 15% to 25% of intracranial aneurysms and carry an estimated risk of rupture of 44%. 1-4 Surgical clipping of PCoA aneurysms bears notable challenges associated with operating in a confined space with limited visualization of deep structures. 1,5 We illustrate the case of a 54-year-old woman who presented with a seven-hour course of intense headaches, vomiting and loss of consciousness. Her neurological examination revealed she had a 4/5 left-sided hemiparesis, a Glasgow coma scale score of 12, and a Hunt and Hess score of 3. A head computed tomography scan without contrast showed subarachnoid hemorrhage in the basal cisterns and Sylvian fissures (Fisher grade 3). Digital subtraction angiography and three-dimensional reconstruction imaging revealed a right bilobed saccular PCoA aneurysm of 4.8 × 5.9 mm projecting anterior-inferiorly. After consideration of her clinical course and aneurysmal features, she underwent a right minipterional craniotomy for exoscopic clipping of the aneurysm neck. The patient tolerated the procedure well, her hemiparesis improved, and she was discharged with a modified Rankin scale score of 1 on postoperative day 3. Exoscopy offered high image quality and expanded 3-dimensional view with digital zoom during the aneurysm repair. 6,7 Although evidence suggests exoscopy is non-inferior to microscopy regarding surgery duration, safety, and outcomes, the capability of providing operator ergonomy during surgery is a worth-noting advantage. 8 IRB and patient consent declaration: This study was exempt from the Institution Review Board because patient consent was granted for the use of clinical information, images, and operative videos. The patient consented to the procedure, and the participants and any identifiable individuals consented to publication of his/her image.

595 Dilemma in the Management of Saccular Aortic Aneurysms

595 Dilemma in the Management of Saccular Aortic Aneurysms

Peculiarities of angiospasm and ischemic complications in ruptures of cerebral arterial aneurysms against the background of occlusive-stenotic lesions of cerebral arteries

Objective – to determine the effect of occlusive-stenotic lesions of cerebral arteries on angiospasm and ischemic complications in patients with ruptured arterial aneurysms against the background of occlusive-stenotic lesions of cerebral arteries. Materials and methods. A retrospective study of the medical histories of 1,147 patients with cerebral artery aneurysms from 2006 to 2022 was conducted. 63 patients were included in the study group because they met the following criteria: surgical treatment; rupture of saccular aneurysms (SAs); the presence of occlusive-stenotic lesions was proven using instrumental examination methods. Patients of the control group had to meet the following criteria: surgical treatment; rupture of SAs; the absence of occlusive-stenotic lesions was proven by means of instrumental examination methods; the gender and age distribution had to match the study group. Of the 126 patients included in this study, there were 76 men (60.32%) and 50 women (39.68%). The age of the patients varied from 31 to 77 years. The average age of patients- 55.9±0.76 years; men – 54.3±0.94 years, women – 58.3±1.19 years. Results. A percentage predominance of patients with high cerebral blood flow velocity (>200 cm/s, which is equal to the velocity with severe grade III vasospasm of the cerebral arteries) in the study group (32.56%) compared with the control group (24.24%) was revealed. Conclusions. The predominance of men among patients of the study group (60.32%) was established. The average age of men with occlusive-stenotic lesions was younger than that of women (men – 54.3±0.94 years, women – 58.3±1.19 years). The difference in age is the largest in the 2nd subgroup of the study group where the severity of stenosis is 50-75% (men - 48.3 years; women - 62 years). Ruptures of arterial aneurysms of the middle cerebral artery occur more often in the presence of stenoses (study group - 25.4%, control group - 12.7%). The neurological status of patients with a hemorrhagic stroke, as a result of the rupture of an arterial aneurysm, is significantly aggravated by occlusive-stenotic lesions due to the occurrence of chronic brain ischemia. The worst prognosis for life and health was in men with a ruptured arterial aneurysm against the background of a 50-75% stenotic lesion and severe vasospasm of the cerebral arteries.

Angiographic Safety and Efficacy of the ReSolv Flow-Diverting Stent in a Rabbit Model.

Bioresorbable polymer-based flow-diverting stents have potential benefits over existing metal devices. This study aimed to evaluate the safety and efficacy of the novel ReSolv device, which is a primarily polymer-based flow-diverting stent, using the in vivo rabbit sidewall saccular aneurysm model. ReSolv stents were deployed in 14 New Zealand White rabbits that had undergone aneurysm creation procedures. Animals were allocated to follow-up time points of 1, 3, 6, 9, 12, 16, or 18 months. Angiographic images were evaluated by an independent neurointerventionalist blinded to follow-up time points for (1) in-stent stenosis, (2) parent vessel and jailed side branch patency, (3) wall apposition, and (4) aneurysm occlusion using the Raymond-Roy Occlusion Classification (RROC), O'Kelly Marotta grading scale, and the 4F flow diversion predictive score. Primary efficacy outcome was defined as RROC Class I or II. At a median follow-up time of 7.5 months, parent vessel (14/14) and jailed side (33/33) branches were patent in all cases. There was no development of thrombus on the stent or cases of significant in-stent stenosis, and all stents had good wall apposition. Adequate occlusion was found in 85.7% (n = 12) of animals, including an RROC Class I in 64.3% (n = 9) and RROC Class II in 21.4% (n = 3). The ReSolv stent shows encouraging angiographic safety and efficacy outcomes after placement in a rabbit sidewall saccular aneurysm model. Longer term studies are ongoing to determine eventual fate of the aneurysm, parent vessel, and jailed side branches after absorption of the polymer component of the stent.

Two-stage hybrid surgical repair for aortic arch pathology with a shaggy aorta: a case report

BackgroundThe surgical treatment strategy for aortic arch pathology with a shaggy aorta must be determined on a case-by-case basis because of the risk of catastrophic complications, such as brain infarction and spinal cord injury.Case presentationThis report describes the surgical case of two saccular aneurysms of the arch and abdominal aorta associated with a shaggy aorta in a 63-year-old man who underwent total arch replacement and secondary thoracic endovascular aortic repair. Considering the risk of embolization during endovascular therapy, graft replacement for the abdominal aortic aneurysm was initially performed. On postoperative day 28, total arch replacement with the conventional elephant trunk was performed using the functional brain isolation technique, which involves manipulating places far from the atherosclerotic burden, such as arterial inflow for cardiopulmonary bypass and unclamping of neck vessels. On postoperative day 7 after total arch replacement, thoracic endovascular aortic repair was performed across the conventional elephant trunk in the nondiseased descending aorta. No postoperative complications, such as cerebrovascular failure, paraplegia, or embolization to abdominal viscera or lower extremities, occurred. The patient remained asymptomatic.ConclusionsThe present case suggests that total arch replacement with the conventional elephant trunk and secondary thoracic endovascular aortic repair may be an effective alternative for aortic arch pathology with a shaggy aorta. The strategy for surgical treatment in patients with aortic arch pathologies with a shaggy aorta must be judged on a case-by-case basis, considering patient characteristics, comorbidities, and preoperative evaluation using transesophageal echocardiography and computed tomography angiography, to eliminate potential determinants of intraoperative stroke.

Appraisal of the Flow Diversion Effect Provided by Braided Intracranial Stents.

Objective: Comparison of the results of stent-assisted coiling (SAC) with braided stents (BS), flow diverters (FD), and laser-cut stents (LCS) to determine the relative flow-diverting capacity of BS (Leo baby and Accero). Methods: Saccular intracranial aneurysms treated by SAC and FD-assisted coiling were retrospectively evaluated. Aneurysm occlusion, as graded per Raymond-Roy score, was categorized as either recanalization/stable residual filling (Group A; lacking a flow diversion effect) or stable/progressive occlusion (Group B with a "flow diversion effect"). Factors predicting the flow diversion effect were evaluated. Results: Of the 194 aneurysms included, LCS, BS, and FD were used in 70 (36.1%), 86 (44.3%), and 38 (19.6%) aneurysms, respectively. Aneurysms treated by FD were larger, had wider necks, and were located on larger parent arteries (p < 0.01, 0.02, and <0.01, respectively). The mean imaging follow-up duration was 24.5 months. There were 29 (14.9%) aneurysms in Group A and 165 (85.1%) in Group B. Among a spectrum of variables, including sex, age, aneurysm size, neck width, parent artery diameter, follow-up duration, and stent type, the positive predictors for stable/progressive aneurysm occlusion were aneurysm size and placement of an FD or BS (p < 0.01 and p < 0.01, respectively, and were positive predictors over LCS: ORs 6.34 (95% CI: 1.62-24.76) and 3.11 (95% CI: 1.20-8.07), respectively) in multivariate analysis. Conclusions: The placement of BS was a predictor of flow diversion over laser-cut stents. However, the flow diversion effect was approximately half that of FDs, suggesting that BS may only be considered to have some (partial) flow diversion effects.

Time-of-flight MRA of intracranial vessels at 7 T

BackgroundThree-dimensional time-of-flight magnetic resonance angiography (TOF-MRA) is a largely adopted non-invasive technique for assessing cerebrovascular diseases. We aimed to optimize the 7-T TOF-MRA acquisition protocol, confirm that it outperforms conventional 3-T TOF-MRA, and compare 7-T TOF-MRA with digital subtraction angiography (DSA) in patients with different vascular pathologies.MethodsSeven-tesla TOF-MRA sequences with different spatial resolutions acquired in four healthy subjects were compared with 3-T TOF-MRA for signal-to-noise and contrast-to-noise ratios as well as using a qualitative scale for vessel visibility and the quantitative Canny algorithm. Four patients with cerebrovascular disease (primary arteritis of the central nervous system, saccular aneurism, arteriovenous malformation, and dural arteriovenous fistula) underwent optimized 7-T TOF-MRA and DSA as reference. Images were compared visually and using the complex-wavelet structural similarity index.ResultsContrast-to-noise ratio was higher at 7 T (4.5 ± 0.8 (mean ± standard deviation)) than at 3 T (2.7 ± 0.9). The mean quality score for all intracranial vessels was higher at 7 T (2.89) than at 3 T (2.28). Angiogram quality demonstrated a better vessel border detection at 7 T than at 3 T (44,166 versus 28,720 pixels). Of 32 parameters used for diagnosing cerebrovascular diseases on DSA, 27 (84%) were detected on 7-T TOF-MRA; the similarity index ranged from 0.52 (dural arteriovenous fistula) to 0.90 (saccular aneurysm).ConclusionsSeven-tesla TOF-MRA outperformed conventional 3-T TOF-MRA in evaluating intracranial vessels and exhibited an excellent image quality when compared to DSA. Seven-tesla TOF-MRA might improve the non-invasive diagnostic approach to several cerebrovascular diseases.Relevance statementAn optimized TOF-MRA sequence at 7 T outperforms 3-T TOF-MRA, opening perspectives to its clinical use for noninvasive diagnosis of paradigmatic pathologies of intracranial vessels.Key points• An optimized 7-T TOF-MRA protocol was selected for comparison with clinical 3-T TOF-MRA for assessing intracranial vessels.• Seven-tesla TOF-MRA outperformed 3-T TOF-MRA in both quantitative and qualitative evaluation.• Seven-tesla TOF-MRA is comparable to DSA for the diagnosis and characterization of intracranial vascular pathologies.Graphical

Clinical and Hemodynamic Features of Aneurysm Rupture in Coil Embolization of Intracranial Aneurysms.

Intraprocedural rupture (IPR) during coil embolization (CE) of an intracranial aneurysm is a significant clinical concern that necessitates a comprehensive understanding of its clinical and hemodynamic predictors. Between January 2012 and December 2023, 435 saccular cerebral aneurysms were treated with CE at our institution. The inclusion criterion was extravasation or coil protrusion during CE. Postoperative data were used to confirm rupture points, and computational fluid dynamics (CFD) analysis was performed to assess hemodynamic characteristics, focusing on maximum pressure (Pmax) and wall shear stress (WSS). IPR occurred in six aneurysms (1.3%; three ruptured and three unruptured), with a dome size of 4.7 ± 1.8 mm and a D/N ratio of 1.5 ± 0.5. There were four aneurysms in the internal carotid artery (ICA), one in the anterior cerebral artery, and one in the middle cerebral artery. ICA aneurysms were treated using adjunctive techniques (three balloon-assisted, one stent-assisted). Two aneurysms (M1M2 and A1) were treated simply, yet had relatively small and misaligned domes. CFD analysis identified the rupture point as a flow impingement zone with Pmax in five aneurysms (83.3%). Time-averaged WSS was locally reduced around this area (1.3 ± 0.7 [Pa]), significantly lower than the aneurysmal dome (p < 0.01). Hemodynamically unstable areas have fragile, thin walls with rupture risk. A microcatheter was inserted along the inflow zone, directed towards the caution area. These findings underscore the importance of identifying hemodynamically unstable areas during CE. Adjunctive techniques should be applied with caution, especially in small aneurysms with axial misalignment, to minimize the rupture risk.

Embolization of a splenic artery aneurysm: a case report

Splenic artery aneurysm (SAA) is the most common aneurysm of the visceral arteries. SAA can be silent and asymptomatic; rupture is a rare but serious complication that can manifest as acute diffuse abdominal pain and hypovolemic shock with a high risk of mortality. Surgery is the traditional treatment, but has the disadvantage of severe surgical injuries, a high risk of complications and a high mortality rate. We present the case of a 58-year-old woman with a saccular aneurysm of the middle segment of the splenic artery; she was treated by coiling embolization using the sandwich technique. Contrast-enhanced computed tomography (CECT) controls at one month, four months and one year showed progressive reduction and complete devascularization of the aneurysmal sac. Embolization of the splenic artery aneurysm is an effective and safe treatment.