Virtual flow diverter deployment and embedding for hemodynamic simulations.

Flow-diverter stents offer clinicians an effective solution for treating intracranial aneurysms, especially in cases where other devices may be unsuitable. However, strongly deviating success rates among different centres, manufacturers, and aneurysm phenotypes highlight the need for better in-situ studies of these devices. To support research in this area, virtual stenting algorithms have been proposed that, combined with computational fluid dynamics, provide insights into the hemodynamic alterations induced by the device. Yet, many existing algorithms rely on uncertain parameters, such as the forces applied during operation, fail to predict the length of the device after deployment, or lack robust validation steps, raising concerns about their reliability. Therefore, we developed a robust deployment technique that builds upon the geometrical features of the vessel and includes advancements from previous works. The algorithm is detailed and validated against literature examples, in-vitro experiments, and patient data, achieving a mean angular error below 5° in the latter. Furthermore, we describe and demonstrate how the deployed device can be embedded in a computational mesh using open-source tools and anisotropic meshing routines.

AnXplore: a comprehensive fluid-structure interaction study of 101 intracranial aneurysms.

Advances in computational fluid dynamics continuously extend the comprehension of aneurysm growth and rupture, intending to assist physicians in devising effective treatment strategies. While most studies have first modelled intracranial aneurysm walls as fully rigid with a focus on understanding blood flow characteristics, some researchers further introduced Fluid-Structure Interaction (FSI) and reported notable haemodynamic alterations for a few aneurysm cases when considering wall compliance. In this work, we explore further this research direction by studying 101 intracranial sidewall aneurysms, emphasizing the differences between rigid and deformable-wall simulations. The proposed dataset along with simulation parameters are shared for the sake of reproducibility. A wide range of haemodynamic patterns has been statistically analyzed with a particular focus on the impact of the wall modelling choice. Notable deviations in flow characteristics and commonly employed risk indicators are reported, particularly with near-dome blood recirculations being significantly impacted by the pulsating dynamics of the walls. This leads to substantial fluctuations in the sac-averaged oscillatory shear index, ranging from -36% to +674% of the standard rigid-wall value. Going a step further, haemodynamics obtained when simulating a flow-diverter stent modelled in conjunction with FSI are showcased for the first time, revealing a 73% increase in systolic sac-average velocity for the compliant-wall setting compared to its rigid counterpart. This last finding demonstrates the decisive impact that FSI modelling can have in predicting treatment outcomes.

Analysis of Intracranial Aneurysm Haemodynamics Altered by Wall Movement.

Computational fluid dynamics is intensively used to deepen our understanding of aneurysm growth and rupture in an attempt to support physicians during therapy planning. Numerous studies assumed fully rigid vessel walls in their simulations, whose sole haemodynamics may fail to provide a satisfactory criterion for rupture risk assessment. Moreover, direct in vivo observations of intracranial aneurysm pulsation were recently reported, encouraging the development of fluid-structure interaction for their modelling and for new assessments. In this work, we describe a new fluid-structure interaction functional setting for the careful evaluation of different aneurysm shapes. The configurations consist of three real aneurysm domes positioned on a toroidal channel. All geometric features, employed meshes, flow quantities, comparisons with the rigid wall model and corresponding plots are provided for the sake of reproducibility. The results emphasise the alteration of flow patterns and haemodynamic descriptors when wall deformations were taken into account compared with a standard rigid wall approach, thereby underlining the impact of fluid-structure interaction modelling.

Non-target embolic events during prostatic embolization with ethylene vinyl alcohol copolymer (EVOH).

BACKGROUND: This study evaluated nontarget embolization (NTE) during prostatic artery embolization (PAE) with ethylene vinyl alcohol copolymer (EVOH). RESULTS: Ten consecutive patients treated by PAE with EVOH for the presence of disabling benign prostatic hyperplasia (BPH)-related lower urinary tract symptoms (LUTS) between June 22 and January 2023 were included in this prospective study. The inclusion criteria were as follows: LUTS attributed to BPH, LUTS duration ≥ 6 months, failure to respond to standard pharmacotherapy, IPSS > 18 or QoL score > 2, and prostate volume > 40 mL. Embolization was performed under general anaesthesia. According to established techniques, a microcatheter was positioned bilaterally within the feeding arteries, and EVOH was injected slowly under X-ray control. Unenhanced pelvic computed tomography scans were carried out before and after embolization to assess the NTE. The safety of the prostatic embolization procedure with EVOH was assessed by collecting adverse effects over 3 months of evaluation that included the International Prostate Symptom Score (IPSS) and quality of life (QoL) score.-up evaluations, occurring at 3, 6, and 12months, included International Prostate Symptom Score. Bilateral PAE was technically successful in 9 patients, and unilateral injection was performed in one patient. The postoperative scanner showed a distribution of the embolization material in the two lobes of the prostate in all patients. The procedure time varied from 120 to 150 (mean: 132) minutes. Eight out of 10 patients developed pollakiuria within 24 h; none of the patients had postoperative pain. Two patients required catheterization for postoperative urinary retention. Catheters were removed successfully at the end of the first day for one of these patients and on the tenth day for the other. At the 3-month follow-up, patients showed significant improvement in the International Prostate Symptom Score (n = 10; mean = -11,5; P < 0.01) and quality of life score (n = 10; mean = -3,40; P < 0.01). Only one patient presented one asymptomatic muscular NTE. CONCLUSIONS: PAE with EVOH is safe, effective, and associated with few NTEs and no postoperative pain. Prospective comparative studies with longer follow-ups are warranted. TRIAL REGISTRATION: IDRCB, 2021-AO29-56-35. Registered 27 May 2022, http://clinicaltrials.gov/study/NCT05395299?cond=embolization&term&rank=1 .

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

BACKGROUND: The 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. METHODS: This 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). RESULTS: A 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. CONCLUSION: This 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 NCT03553771.

Effectiveness of Geniculate Artery Embolization for Chronic Pain after Total Knee Replacement-A Pilot Study.

PURPOSE: To evaluate the efficacy and safety of embolization of hyperemic synovial tissue for the treatment of persistent pain after total knee arthroplasty (TKA). MATERIALS AND METHODS: Twelve patients with persistent pain after TKA were enrolled in this prospective, single-center pilot study. Genicular artery embolization (GAE) was performed using 75-µm spherical particles. The patients were assessed using a 100-point Visual Analog Scale (VAS) and Knee Injury and Osteoarthritis Outcome Score (KOOS) at baseline and 3 and 6 months thereafter. Adverse events were recorded at all time points. RESULTS: A mean of 1.8 ± 0.8 abnormal hyperemic genicular arteries were identified and embolized, with a median volume of diluted embolic material of 4.3 mL in all 12 (100%) patients. The mean VAS score on walking improved from 73 ± 16 at baseline to 38 ± 35 at the 6-month follow-up (P < .05). The mean KOOS pain score improved from 43.6 ± 15.5 at baseline to 64.6 ± 27.1 at the 6-month follow-up (P < .05). At the 6-month follow-up, 55% and 73% of the patients attained a minimal clinically important change in pain and quality of life, respectively. Self-limited skin discoloration occurred in 5 (42%) patients. The VAS score increased by more than 20 immediately after embolization in 4 (30%) patients, who required analgesic treatment for 1 week. CONCLUSION: GAE is a safe method of treating persistent pain after TKA that demonstrates potential efficacy at 12 months.

Use of the Rocket Technique after Failure of the Direct Aspiration First-Pass Technique in Acute Stroke Thrombectomy.

The technical feasibility of the rocket technique was evaluated for patients treated for stroke where the direct aspiration first-pass technique (ADAPT) failed to reach the occlusion site. This single-center retrospective study included data on consecutive patients with a large vessel occlusion of the anterior circulation who underwent mechanical thrombectomy. Of 138 patients, 100 met the inclusion criteria. In 84 patients, a large 0.072-inch inner lumen aspiration catheter was able to reach the occlusion site when deployed with a coaxial microcatheter. In 16 patients, this technique failed, and the microcatheter was replaced with a compliant balloon inflated at the extremity of the aspiration catheter (rocket technique). In 15 of these 16 patients, the rocket technique brought the catheter into contact with the thrombus. In conclusion, when deployment of the ADAPT with a coaxial microcatheter fails to reach the clot site, the rocket technique can safely advance the aspiration catheter to the clot.

Non-ischemic cerebral enhancing lesions after thrombectomy: a multicentric retrospective French national registry.

To report the occurrence of non-ischemic cerebral enhancing (NICE) lesions following mechanical thrombectomy (MT) through the retrospective French nationwide registry of NICE lesions. All thrombectomy capable stroke centers (TSC) in France were invited to fill out a questionnaire disseminated through a trainee-led research network (JENI-RC: Jeunes en Neuroradiologie Interventionnelle-Research Collaborative). NICE lesions were defined according to previous literature as delayed onset punctate, nodular, or annular foci enhancements with peri-lesion edema and vascular distribution in the territory of the MT with no other confounding disease. All 43 TSC French centers responded. Three patients were reported by 3 different centers over a total of 34,824 MT (2015-2020). Patient no. 1 developed symptomatic NICE lesions 8 weeks after MT with combination of aspiration and stentriever for a right middle cerebral artery occlusion. Patient no. 2 developed asymptomatic NICE lesions 5 weeks after MT with direct thromboaspiration for a right middle cerebral artery occlusion. Patient no. 3 developed symptomatic NICE lesions 6 weeks after MT with direct thromboaspiration, and combination of aspiration and stentriever for a basilar artery occlusion. This study provides evidence that NICE lesions following MT are a possible rare complication with a similar presentation as previously described following endovascular aneurysm treatment. Both radiologists and neurologists should be aware of this adverse event and make use of MRI contrast agents in case of unexplained symptoms/images during follow-up after MT.

Combined Omic Analyzes of Cerebral Thrombi: A New Molecular Approach to Identify Cardioembolic Stroke Origin.

Background and Purpose: The diagnosis of cardioembolic stroke can be challenging for patient management in secondary stroke prevention, particularly in the case of covert paroxysmal atrial fibrillation. The molecular composition of a cerebral thrombus is related to its origin. Therefore, proteomic and metabolomic analyses of the retrieved thrombotic material should allow the identification of biomarkers or signatures to improve the etiological diagnosis of stroke. Methods: In this pilot study, the proteome and metabolome of cerebral thrombi from atherothrombotic and cardioembolic stroke patients were studied according to ASCOD phenotyping (A: atherosclerosis; S: small-vessel disease; C: cardiac pathology; O: other causes; D: dissection), with the highest causality grade, from the ThrombiOMIC cohort (consecutive patients with stroke recanalized by mechanical thrombectomy in an acute phase). Proteomic and metabolomic results were used separately or combined, and the obtained omic signatures were compared with classical cardioembolic stroke predictors using pairwise comparisons of the area under receiver operating characteristics. Results: Among 59 patients of the ThrombiOMIC cohort, 34 patients with stroke showed a cardioembolic phenotype and 7 had an atherothrombotic phenotype. Two thousand four hundred fifty-six proteins and 5019 molecular features of the cerebral thrombi were identified using untargeted proteomic and metabolomic approaches, respectively. Area under receiver operating characteristics to predict the cardioembolic origin of stroke were calculated using the proteomic results (0.945 [95% CI, 0.871­1]), the metabolomic results (0.836 [95% CI, 0.714­0.958]), and combined signatures (0.996 [95% CI, 0.984­1]). The diagnostic performance of the combined signatures was significantly higher than that of classical predictors such as the plasmatic BNP (B-type natriuretic peptide) level (area under receiver operating characteristics, 0.803 [95% CI, 0.629­0.976]). Conclusions: The combined proteomic and metabolomic analyses of retrieved cerebral thrombi is a very promising molecular approach to predict the cardioembolic cause of stroke and to improve secondary stroke prevention strategies.

Metabolome of Cerebral Thrombi Reveals an Association between High Glycemia at Stroke Onset and Good Clinical Outcome.

Despite the fact that glucose is the main fuel of the brain, hyperglycemia at hospital admission is generally associated with a poor functional outcome in stroke patients. This paradox may be explained by the lack of information about the blood glucose level at stroke onset. Here, we analyzed the metabolome of blood cells entrapped in cerebral thrombi to gain insight into their metabolism at stroke onset. Fourty-one consecutive stroke patients completely recanalized by mechanical thrombectomy within 6 h were included. The metabolome of retrieved thrombi was analyzed by liquid chromatography tandem with mass spectrometry. Discriminant Analysis (sparse Partial Least Squares Discriminant Analysis (sPLS-DA)) was performed to identify classification models and significant associated features of favorable clinical outcome at 3 months (modified Rankin Scale (mRS) < 2). sPLS-DA of the metabolomes of cerebral thrombi discriminated between stroke patients with a favorable or poor clinical outcome (Area Under the Curve (AUC) = 0.992 (0.931-1)). In addition, our results revealed that high sorbitol and glucose levels in the thrombi positively correlated with favorable clinical outcomes. Sorbitol, a short-term glycemic index reflecting a high blood glucose level at stroke onset, was found to be an independent predictor of good outcome (AUC = 0.908 (0.807-0.995)). This study demonstrates that a high blood glucose level at stroke onset is beneficial to the clinical outcome of the patient.

Endovascular Occlusion of Neovascularization as a Treatment for Persistent Pain After Total Knee Arthroplasty.

Approximately 20% of patients have persistent unexplained pain after total knee arthroplasty (TKA). Currently available treatments are unsatisfactory. The present report describes four patients in whom transcatheter arterial embolization had a remarkable effect on pain after TKA. Abnormal neovessels were identified in all patients. For 48 h, one patient experienced remarkable postprocedural pain at the inner side of the knee that was subsided by level 1 analgesics and another patient development of a spontaneous skin ulceration resolving within 8 days. The mean Knee injury and Osteoarthritis Outcome Score pain subtotal had increased from 39 to 82 one month after treatment. Endovascular occlusion of neovascularization, decreasing chronic inflammation and the growth of unmyelinated sensory nerves may be treatment options for persistent unexplained pain following TKA.Level of Evidence IV, Case report.

Safety and effectiveness of the Low Profile Visualized Intraluminal Support (LVIS and LVIS Jr) devices in the endovascular treatment of intracranial aneurysms: results of the TRAIL multicenter observational study.

BACKGROUND AND PURPOSE: To evaluate the safety and effectiveness of the low-profile braided intracranial stents called the Low Profile Visualized Intraluminal Support (LVIS) devices for stent-assisted coil embolization of wide-necked intracranial aneurysms. MATERIALS AND METHODS: This was a prospective, multicenter, observational study of unruptured and ruptured intracranial aneurysms treated with the LVIS devices. Imaging and clinical data were independently analyzed respectively by CoreLab and Clinical Event Committee. Primary endpoints were clinical safety, effectiveness, and angiographic stability of the results at 6 and 18 months. RESULTS: Ten centers participated in the study; 102 patients were included and 90 patients (42.2% men, 57.8% women) were eventually analyzed, among which 27 (30.0%) had multiple aneurysms. Twenty-three (25.6%) were ruptured aneurysms, four of which (4.4%) were treated in the acute phase. One aneurysm was treated per patient; 92 LVIS and LVIS Jr devices were placed overall. The total aneurysm occlusion rate was 91.0% on immediate post-procedure angiograms, which remained unchanged at 6-month follow-up and was 92.4% at 18-month follow-up. One patient (1.1%) underwent retreatment between 6 and 18 months of follow-up. A modified Rankin score of 0 was documented for most cases immediately after the procedure (86.7%) and at 6-month (86.8%) and 18-month (83.3%) follow-up. The overall permanent morbidity rate at 18 months was 5.6% and the overall rate of events with sequelae related to the stent was 2.2%. The 18-month procedure-related mortality rate was 3.3%. No patient was deemed to require retreatment at 18-month follow-up. CONCLUSION: The LVIS/LVIS Jr endovascular devices are safe and effective in the treatment of ruptured and unruptured intracranial aneurysms, with acceptable complication rates, very high immediate total occlusion rates, and stable angiographic results.

Should we treat aneurysms in perforator arteries from the basilar trunk? Review of 49 cases published in the literature and presentation of three personal cases.

Basilar trunk perforator artery aneurysms are rare. Their diagnosis and treatment are difficult, controversial, and challenging. Analysis of 52 cases (49 documented in the literature and three personal cases) clearly shows a re-bleeding rate of 15% in patients whose aneurysm has not been occluded and 0% in treated patients ( p < 0.05). The most effective treatment, and the one that presents the least complication, is double-stenting across the basilar trunk.

Stent-assisted coiling of intracranial aneurysms using LEO stents: long-term follow-up in 153 patients.

PURPOSE: Coiling associated with placement of a self-expandable intracranial stent has improved the treatment of intracranial wide-necked aneurysms. Little is known, however, about the durability of this treatment. The purpose of this report is to present our experience with the LEO stent and to evaluate the complications, effectiveness, and long-term results of this technique. METHODS: We analyzed the records of 155 intracranial unruptured aneurysms that were treated by stent-assisted coiling with a LEO stent between 2008 and 2012. Procedural, early post-procedural, and delayed complications were recorded. Clinical and angiographic follow-up of patients was conducted over a period of at least 36 months. RESULTS: No procedural mortality was observed. One-month morbidity was observed in 14 out of 153 patients (9,15%). One hundred thirty-eight patients (with 140 aneurysms) had clinical and angiographic follow-up for more than 36 months. No aneurysm rupture was observed during follow-up. Four patients presented an intra-stent stenosis at 8 months, and 6 patients who had an early recurrence were retreated. Final results showed 85% complete occlusion, 13% neck remnants, and 2% stable incomplete occlusion. CONCLUSION: Stent-assisted coiling with the LEO stent is a safe and effective treatment for unruptured intracranial aneurysms. The long-term clinical outcomes with the LEO stent are excellent with a high rate of complete occlusion that is stable over time.

Super-selective coil embolization of a basilar perforator artery aneurysm previously treated by the stent-in-stent technique, using an extremely soft bare coil delivered through a one-marker microcatheter.

Background Aneurysms of the perforating arteries arising from the basilar artery trunk are rare and represent a therapeutic challenge. Methods A basilar perforator aneurysm was initially treated by the stent-in-stent technique. Enlargement of the aneurysm was seen on follow up and the sac was secondarily coiled using two extremely soft bare coils, delivered through a one-marker microcatheter. Results At 6 months, the patient had a modified Rankin Scale score of 0 and cerebral arteriography demonstrated complete occlusion of the lesion. Conclusions We describe, as far as we are aware, the first case of basilar perforator aneurysm occlusion using extremely soft bare coils, inserted through the mesh of two stents previously placed in the basilar trunk.

Prasugrel versus clopidogrel in stent-assisted coil embolization of unruptured intracranial aneurysms.

Background Thromboembolic complications are the main problem in stent-assisted coil embolization of unruptured intracranial aneurysms. The combination of aspirin and clopidogrel is generally used to decrease these complications, but some patients do not respond to clopidogrel and have a higher risk of stent thrombosis. In cardiology, clinical trials have shown that prasugrel reduced the incidence of ischaemic events in patients with acute coronary syndrome compared with clopidogrel but, according to several authors, prasugrel would produce an increased risk of cerebral haemorrhagic complications. Objective The purpose of this study was to determine whether prasugrel would be more effective than clopidogrel in reducing procedural events in patients with an unruptured aneurysm treated endovascularly with coils and stent. Materials and methods Two hundred consecutive patients with intracranial aneurysms were treated using coiling and stenting procedures. The first 100 patients were administered a dual antiplatelet of aspirin and clopidogrel, while the remaining 100 patients were administered a dual antiplatelet of aspirin and prasugrel. In each group data were collected on procedural and periprocedural haemorrhagic and ischaemic complications. Results Aneurysmal occlusion and haemorrhagic complications rates were identical in both groups. The number of thromboembolic events observed in the two groups of our study did not differ significantly, but the prasugrel group included more wide-neck aneurysms and more flow-diverted stents. Moreover, complications in the prasugrel group were more benign, explaining the significant difference in clinical outcomes between the two groups on Day 30. Conclusions Prasugrel reduces the clinical consequences of thromboembolic complications of endovascular treatment with stenting and coiling of unruptured intracranial aneurysms.

Compressive hematoma and deep arteriovenous malformation: Emergency endovascular occlusion via a venous approach with surgical evacuation of the hematoma.

Compressive hematoma associated with deep arterio-venous malformation is a difficult surgery. Arterial presurgical embolization is often indicated but rarely effective. Endovascular occlusion via a venous approach is a technique that has recently been undertaken successfully to treat certain types of sub-pial vascular malformation. The venous endovascular approach has succeeded in a 20-year-old man of who presented with a compressive hematoma due to rupture of a deep arteriovenous malformation. By fully endovascular occlusion, the surgery consisted of surgical removal of the hematoma, with reduced cortical damage.