Interventional Neuroradiology最新文献

Background: Endovascular thrombectomy(EVT) is the standard of care for large vessel occlusion(LVO) stroke. Data on technical and clinical outcome in proximal medium vessel occlusions(pMeVOs) comparing frontline techniques remain limited.

Methods: We report an international multicenter retrospective study of patients undergoing EVT for stroke at 32 centers between 2015-2021. Patients were divided into LVOs(ICA/M1/Vertebrobasilar) or pMeVOs(M2/A1/P1) and categorized by thrombectomy technique. Primary outcome was 90-day good functional outcome(mRS ≤ 2). Multivariate logistic regressions were used to evaluate the impact of technical variables on clinical outcomes. Propensity score matching was used to compare outcome in patients with pMeVO treated with aspiration versus stent-retriever.

Results: In the cohort of 5977 LVO and 1287 pMeVO patients, pMeVO did not independently predict good-outcome(p  =  0.55). In pMeVO patients, successful recanalization irrespective of frontline technique(aOR = 3.2,p < 0.05), procedure time ≤ 1-h(aOR = 2.2,p < 0.05), and thrombectomy attempts ≤ 4(aOR =  2.8,p < 0.05) were independent predictors of good-outcomes.In a propensity-matched cohort of aspiration versus stent-retriever pMeVO patients, there was no difference in good-outcomes. The rates of hemorrhage were higher(9%vs.4%,p < 0.01) and procedure time longer(51-min vs. 33-min,p < 0.01) with stent-retriever, while the number of attempts was higher with aspiration(2.5vs.2,p < 0.01). Rates of hemorrhage and good-outcome showed an exponential relationship to procedural metrics, and were more dependent on time in the aspiration group compared to attempts in the stent-retriever group.

Conclusions: Clinical outcomes following EVT for pMeVO are comparable to those in LVOs. The golden hour or 3-pass rules in LVO thrombectomy still apply to pMeVO thrombectomy. Different techniques may exhibit different futility metrics; SR thrombectomy was more influenced by attempts whereas aspiration was more dependent on procedure time.

Purpose: Outcome prediction of large vessel occlusion of the anterior circulation in patients with wake-up stroke is important to identify patients that will benefit from thrombectomy. Currently, mismatch concepts that require MRI or CT-Perfusion (CTP) are recommended to identify these patients. We evaluated machine learning algorithms in their ability to discriminate between patients with favorable (defined as a modified Rankin Scale (mRS) score of 0-2) and unfavorable (mRS 3-6) outcome and between patients with poor (mRS5-6) and non-poor (mRS 0-4) outcome.

Methods: Data of 8395 patients that were treated between 2018 and 2020 from the nationwide registry of the German Society for Neuroradiology was retrospectively analyzed. Five models were trained with clinical variables and Alberta Stroke Program Early CT Score (ASPECTS). The model with the highest accuracy was validated with a test dataset with known stroke onset and with a test dataset that consisted only of wake-up strokes.

Results: 2419 patients showed poor and 3310 patients showed favorable outcome. The best performing Random Forest model achieved a sensitivity of 0.65, a specificity of 0.81 and an AUC of 0.79 on the test dataset of patients with wake-up stroke in the classification analysis between favorable and unfavorable outcome and a sensitivity of 0.42, a specificity of 0.83 and an AUC of 0.72 in the classification analysis between poor and non-poor outcome.

Conclusion: Machine learning algorithms have the potential to aid in the decision making for thrombectomy in patients with wake-up stroke especially in hospitals, where emergency CTP or MRI imaging is not available.

Background: Several variations of the combined thrombectomy technique for acute ischemic stroke using a stent retriever and aspiration catheter have been described. The aim of our study was to assess how the presence of the microcatheter and stent retriever affect the basic aspiration parameters, namely, flow rate and aspiration force, depending on their position within the aspiration catheter.

Methods: Two experimental set-ups were designed to assess changes in flow rate and aspiration force according to the position of the stent retriever and microcatheter within the aspiration catheter.

Results: The transition of the stent retriever and microcatheter from the distal to proximal position resulted in a progressive increase in the flow rate, but with no impact on aspiration force. Additionally, the size of the stent retriever had no significant effect on flow rate changes and the reduction in flow rate was related to the microcatheter diameter. Negative pressure generated inside the aspiration catheter impacted on its distal segment located beyond the radiopaque marker, thus leading to its partial collapse. As a consequence, the measured aspiration force was lower than the theoretical aspiration force level for all tested aspiration catheters.

Conclusions: In our experimental model, the position of the stent retriever and microcatheter within the aspirator catheter affected the flow rate, but not the aspiration force. Negative pressure generated within the aspiration catheter appeared to determine a partial collapse of the distal segment that resulted in a less effective aspiration force than the theoretical aspiration force level.

Mechanical thrombectomy for distal, medium vessel occlusions is gaining importance and increasingly performed. However, there is an ongoing debate on selection criteria for thrombectomy and the best techniques for fast and effective complete reperfusion. Here, we present a case where we use a combination of a stent retriever and aspration catheter for a distal middle cerebral artery occlusion (M3-segment). The aspiration catheter was advanced over the wire of the stent-retriever after deployment - but not using a blind exchange with the mini-pinning technique as previously described. Instead, a new extension wire to the stent retriever was used to advance the aspiration catheter safely. This technique can be important in the near future as distal occlusions will be treated more regularly and trials randomizing patients with distal occlusions such as the Distal trial are underway.

Intracranial dural arteriovenous fistulas (dAVF) account for nearly 10-15% of all arteriovenous malformations. Although the majority of dAVF are effectively cured after endovascular intervention, there are cases of dAVFs that may recur after radiographic cure. We present the case of a 69-year-old female with de novo formation of three dAVFs in different anatomic locations after successive endovascular treatments. The patient's initial dAVF was identified in the right posterior frontal convexity region and obliterated with transarterial and transvenous embolization. The patient returned eight years later due to left-sided pulsatile tinnitus and a new dAVF in the left greater sphenoid wing region was seen on angiography. This was treated with transvenous embolization with complete resolution. One year later, she developed left sided pulsatile tinnitus again and was found to have a left carotid-cavernous dAVF. This is the first case report to our knowledge of the formation of three de novo dAVFs over multiple years in distinct anatomical locations. We also review the literature regarding de novo dAVFs after endovascular treatment which includes 16 cases. De novo dAVF formation is likely due to numerous factors including changes in venous flow and aberrant vascular development. It is important to further understand the relationship between endovascular treatment and recurrent dAVF formation to prevent subsequent malformations.

Objective: The Contour Neurovascular System (CNS) is a novel intrasaccular flow disrupting device with a semi-3D cup-like shape for the treatment of intracranial aneurysms. This study investigates the potential and limitations of the CNS for embolization of aneurysm remnants after previous treatment.

Methods: Ten cases of aneurysm recurrence treatment with the CNS were analyzed from a single-center database. Technical success, procedural aspects, complications, and angiographic results were evaluated.

Results: The aneurysms (median width: 5.3 mm, median neck width: 3.8 mm) were located in the anterior communicating artery (4), basilar tip (3), internal carotid artery (1), middle cerebral artery (1), and superior cerebellar artery (1). The aneurysms were initially treated endovascularly (9) and by clipping (1). Retreatment failed in one case where the smallest available CNS proved to be too small and had to be removed. Adjunctive coiling was performed in two large remnants of partially thrombosed basilar tip aneurysms. There were no procedural complications or morbidity. At a median follow-up of nine months, 4/8 (50%) aneurysms were completely occluded, 2/8 (25%) had neck remnants, and 2/8 (25%) had aneurysm remnants. The two aneurysm remnants were retreated with coiling and stent-assisted coiling, respectively.

Conclusions: CNS treatment of aneurysm remnants may be feasible, especially for shallow, wide-necked aneurysm geometries. Further studies are needed to identify aneurysm subsets that benefit from CNS retreatment and to define mid- and long-term occlusion rates.

Background: Mechanical thrombectomy (MT) is the gold standard treatment for large vessel occlusion (LVO). A vital factor that might influence MT outcomes is the use of intravenous thrombolysis (IVT). A few clinical trials in this domain thus far have not yielded consistent outcomes. We conducted this meta-analysis to synthesize collective evidence in this regard.

Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement guidelines were followed, and we performed a comprehensive literature search of four databases (PubMed, Scopus, Web of Science, Cochrane CENTRAL). For outcomes constituting continuous data, the mean difference (MD) and its standard deviation (SD) were pooled. For outcomes constituting dichotomous data, the frequency of events and the total number of patients were pooled as the risk ratio (RR).

Results: Seven clinical trials with a total of 2317 patients are included in this meta-analysis. Six trials are randomized, and one trial was nonrandomized. No significant differences were found between MT plus IVT and MT alone in successful recanalization (RR 1.04, 95% Confidence Interval (CI) [0.92 to 1.17], P = 0.53), 90-day functional independence (RR 1.03, 95% CI [0.90 to 1.19], P = 0.65), symptomatic intracranial hemorrhage (sICH) (RR 1.22, 95% CI [0.84 to 1.75], P = 0.30), or mortality (RR 0.94, 95% CI [0.76 to 1.18], P = 0.61).

Conclusion: The current evidence does not favor either MT plus IVT or MT alone for LVO except for the procedural time. More trials are needed in this regard, and certain factors should be considered when comparing the two approaches.

Introduction: Venous sinus stenting is a well established alternative to cerebrospinal fluid diversion for the treatment of idiopathic intracranial hypertension (IIH) with associated venous sinus stenosis. During this procedure, distal guide catheter placement within the venous sinuses may be desirable to facilitate stent delivery. We report our initial experience using the TracStar LDP™ (Imperative Care, Campbell, USA, 0.088-inch inner diameter) as the guide catheter for intracranial access during venous sinus stenting.

Methods: A multi-institutional retrospective chart review of a prospectively maintained IRB-approved database was performed. Consecutive patients who underwent venous sinus stenting from 1/1/2020-9/6/2021 for IIH were included. Patient characteristics, procedural details, TracStar distal reach, outcomes, and complications were collected and analyzed.

Results: Fifty-eight patients were included. The mean age was 33.8 years and 93.1% of patients were female. Visual changes prompted evaluation in 86.2% of patients. Stent placement was successful in all patients. The TracStar LDP catheter was advanced to the location of stent placement in 97.9% of cases in which it was attempted. The large 0.088-inch inner diameter lumen enabled compatibility with all desired stent sizes ranging from six to 10 millimeters. Gradient pressure across transverse sinus stenosis dropped from an average of 19.5 mmHg pre-procedure to 1.7 mmHg post-stent placement (p < 0.001). Clinical improvement was achieved in 87.9% (51/58) of patients. There were no catheter-related complications.

Conclusion: The TracStar LDP is a safe and effective access platform for reaching treatment locations in patients who present with idiopathic intracranial hypertension and who are candidates for venous sinus stent placement.

Introduction: Staged, transarterial embolization (TAE) is currently considered the gold standard for the treatment of vein of Galen aneurysmal malformation (VGAM); however, as transarterial access becomes restricted, further staged TAE may become ineffective or carry an increased risk of hemorrhagic or ischemic stroke when attempting complete obliteration.

Objective: To describe the first consecutive, retrospective series of VGAM treated with transvenous embolization (TVE) with coils alone, as the final treatment in staged endovascular therapy, at a single institution between January 2004 and September 2021.

Results: A total of 10 patients with a median age of 5.5 (IQR: 9.25) years were treated with coiling TVE. Patients were treated with a median number of 5 (IQR: 2.75) TAEs prior to the final TVE treatment. Complete or near-complete immediate angiographic obliteration was achieved in eight patients. Immediate post-procedural (within 48 h) hemorrhagic complications were noted in two patients (20%), one of whom passed away while the second suffered from hemiparesis. Stereotactic radiosurgery was performed in two patients with incomplete obliteration after TVE. The median follow-up time after TVE was 17 (IQR: 9) months. At long-term follow up (17 months) for the remaining nine patients, all VGAMs were completely obliterated. Long-term clinical deterioration compared to pre-TVE was noticed in one case.

Conclusion: Transvenous coil embolization is a technically feasible but risky option, as a final-stage treatment for cure of VGAMs with restricted trans-arterial access. Although TVE with coils remains an effective therapeutic modality, we recommend continuing investigation of safer TVE techniques to achieve cure.