Citations

Historically, the management of carotid artery disease has primarily focused on the degree of stenosis as the main indicator for assessing stroke etiology, risk, and need for intervention. However, accumulating evidence suggests that structural and biological features within the arterial wall, such as intraplaque hemorrhage, may have superior diagnostic, prognostic, and therapeutic values. Under current guidelines, unless an atheroma results in ≥50% stenosis, it is not considered the cause of a cerebrovascular event. This results in extensive and often unproductive diagnostic workup, prescription of ineffective medical therapy, and preclusion of patients from receiving revascularization procedures that have been shown to prevent recurrent cerebrovascular events in cases of ≥50% stenosis. A subset of embolic strokes of undetermined source, which account for up to 25% of all ischemic cerebrovascular events, are thought to be due to thromboembolic phenomena from undiagnosed plaque disruptions in nonstenotic arteries (<50% stenosis). Recently, it has been proposed to reclassify this subgroup of patients as symptomatic nonstenotic carotid if the carotid plaque ipsilateral to the cerebrovascular event presents with high-risk features including intraplaque hemorrhage, lipid-rich necrotic core, thinning/rupture of the fibrous cap, and ulceration. In this review, we first provide a historical overview of the chain of events and circumstances that resulted in the present management of carotid artery disease. Second, we embed the contemporary biomarkers of plaque vulnerability in a modern mechanistic paradigm of carotid plaque disruption and thromboembolization. Third, we review the clinically available imaging tools to detect these biomarkers, and how their use has started to shed light on the prevalence and natural history of this underdiagnosed condition. Fourth, we review recent clinical studies employing a contemporary definition of symptomatic nonstenotic carotid and discuss targeted treatments for this condition. Finally, we make a case to generate the much-needed high-level evidence to align the clinical management of patients with symptomatic nonstenotic carotid with a contemporary understanding of plaque disruption and thromboembolization.

BACKGROUND AND OBJECTIVES: First-line therapy for most intracranial dural arteriovenous fistulas (dAVFs) is endovascular embolization, but some require microsurgical ligation due to limited endovascular accessibility, anticipated lower cure rates, or unacceptable risk profiles. We investigated the most common surgically treated dAVF locations and the approaches and outcomes of each. METHODS: The Consortium for Dural Arteriovenous Fistula Outcomes Research database was retrospectively reviewed. Patients who underwent dAVF microsurgical ligation were included. Patient demographics, angiographic information, surgical details, and postoperative outcomes were collected. The 5 most common surgically treated dAVF locations were analyzed about used surgical approaches and postoperative outcomes. Univariate analyses were performed with statistical significance set at a threshold of P < .05. RESULTS: In total, 248 patients in the Consortium for Dural Arteriovenous Fistula Outcomes Research database met inclusion criteria. The 5 most common surgically treated dAVF locations were tentorial, anterior cranial fossa (ACF), transverse-sigmoid sinus (TSS), convexity/superior sagittal sinus (SSS), and torcular. Most tentorial dAVFs were approached using a suboccipital, lateral supracerebellar infratentorial approach (39.3%); extended retrosigmoid approach (ERS) (25%); or posterior subtemporal approach (19.6%). All ACF dAVFs used a subfrontal approach; 5.3% also included an anterior interhemispheric approach. Most TSS dAVFs were ligated via ERS (31.3%) or subtemporal (31.3%) approaches. All convexity/SSS dAVFs used an interhemispheric approach. All torcular dAVFs used the suboccipital, lateral supracerebellar infratentorial approach, with 10.5% undergoing simultaneous ERS craniotomy. Angiographic occlusion rates after microsurgery were 85.5%, 100%, 75.8%, 79.2%, and 73.7% for tentorial, ACF, TSS, convexity/SSS, and torcular dAVFs, respectively ( P = .02); the permanent neurological complication rates were 1.8%, 2.6%, 9.1%, 0%, and 0% ( P = .31). There were no statistically significant differences in development of complications ( P = .08) or Modified Rankin Scale at the last follow-up ( P = .11) by fistula location. CONCLUSION: Although endovascular embolization is the first-line treatment for most intracranial dAVFs, surgical ligation is an important alternative. ACF and tentorial fistulas particularly demonstrate high rates of postoperative obliteration.

Background Cerebral sinus venous thrombosis (CSVT) has traditionally been treated medically with systemic anticoagulation. Recent advances in endovascular therapy (EVT) may represent an alternative treatment to medical therapy for CSVT. We conducted a systematic review and meta-analysis to evaluate the use of EVT for CSVT. Methods We conducted a systematic literature review using PubMed, Embase, Scopus, and Web of Science. We included studies that reported outcomes following EVT for CSVT. The primary outcome of interest was rate of modified Rankin Scale (mRS) 0–2. Secondary outcomes of interest were rates of complete, partial, and failed recanalization, mortality, and new or expansion of hematoma. We calculated pooled rates (%) and their corresponding 95% confidence intervals (CIs). Results Thirty-eight studies with 682 patients were included. Rate of mRS 0–2 was 82.6% (95% CI, 75.3%–88.0%). Rate of complete recanalization was 60.9% (95% CI, 49.1%–71.5%), rate of partial recanalization was 34.2% (95% CI, 24.1%–45.9%), and rate of failed recanalization was 5.4% (95% CI, 3.1%–9.2%). Rate of mortality was 6.7% (95% CI, 4.1%–10.8%), and rate of new hematoma or expansion of hematoma was 5.1% (2.9%–8.8%). Conclusions In this systematic review and meta-analysis, EVT for CSVT was associated with favorable rates of mRS 0–2 and recanalization. Furthermore, EVT was associated with a promising safety profile. Future prospective, comparative studies are warranted to assess EVT for CSVT.

Background Many devices are used to perform mechanical thrombectomy in the setting of large vessel occlusion acute ischemic stroke. We sought to evaluate the efficacy and safety of pRESET stent-retriever systems. Methods We conducted a comprehensive systematic review and meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant studies up to March 2024 were retrieved from PubMed, Scopus, Web of Science, and Embase databases. Results A total of 8 papers met the inclusion/exclusion criteria comprising a total of 1140 participants (average age 72.4 ± 11.9, female percentage (50%). Preintervention intravenous thrombolysis was utilized in 46.5% (range 32.9–65.4) of patients, with a median National Institute of Health Stroke Scale at presentation of 15 (range 0–38). The middle cerebral artery was the most commonly affected artery, with a prevalence of 76.4% (range 62.8–100). The pRESET stent-retriever systems demonstrated a first-passing effect rate of 53.4% [95% confidence interval [CI] 44.8; 61.7] and a final thrombolysis in cerebral infarction 2b-3 grade rate of 90.41% [95% CI 82.13; 95.08]. Ninety-day modified Rankin Scale (0–2) rate was 42.2% [95% CI 27.6; 58.4], and 90-day mortality rate was 15.1% [95% CI 9.8; 22.6]. Postintervention hemorrhage occurred at a rate of 28.6% [CI 17.2; 43.6]. Conclusion Our systematic review and meta-analysis describes the efficacy of the pRESET stent retriever system in managing acute ischemic stroke patients. The pRESET device was found to have a similar safety and efficacy profile to other mechanical thrombectomy devices currently in use.

Purpose Optimizing the preparation of a 10 ml syringe for manual injection of contrast media can help operators obtain easier and faster injections. This study aims to compare the flow rates of different contrast media injection methods. Methods Different contrast media solutions were compared: 100% contrast (10 ml contrast), mixed contrast solution (8:2 contrast/saline), and layered contrast below saline (“Parfait”) in different volumes. Contrast media were injected at room temperature (20°C) and after heating (37°C). Four operators injected 10 ml syringes filled with different mediums through 5-French angiographic catheters. The average flow rate was used to compare different contrast injection mediums. The Kruskal-Wallis test with post-hoc pairwise comparisons using Bonferroni correction or Mann-Whitney U-tests were employed depending on the type of comparison. Results Compared to the 100% contrast solution, every Parfait media and mixed contrast solution demonstrated significantly higher flow rates (p < 0.001). The 5 ml saline Parfait had the highest flow rate among the Parfait solutions. The 5 ml saline Parfait and the mixed solution had comparable flow rates (p = 0.237). Higher flow rates were observed upon heating both 100% contrast (p < 0.001) and mixed contrast solutions (p < 0.001) in comparison to their flow rates at room temperature. Conclusion This study demonstrates the capability of the Parfait and mixed contrast injections to achieve higher flow rates than the 100% contrast solutions. Heating the contrast media to 37°C also proves to be a viable strategy for further enhancing the flow rates for 100% and mixed contrast solutions.

Background A higher number of recanalization attempts reduces the efficacy of endovascular thrombectomy (EVT) for acute ischemic stroke secondary to large vessel occlusion (LVO). We assessed the impact of switching EVT techniques after a failed first pass on procedural and clinical outcomes. Methods This multicenter international study, conducted between January 2013 and December 2022, included patients undergoing EVT for anterior circulation LVO (internal carotid artery or M1 segments) with failed first pass recanalization. Propensity score matching identified a 1:1 matched cohort of patients in whom EVT technique was changed after a failed first pass and those with the same technique repeated. The primary outcome was successful recanalization at second attempt defined as Thrombolysis in Cerebral Ischemia (TICI) score of 2B or higher. Secondary outcomes were 90-day modified Rankin Score (mRS) and postprocedural hemorrhage. Results Among 2167 patients, converting to an alternative technique after a failed first pass was associated with higher odds of successful recanalization (adjusted OR (aOR)=1.5, p=0.041), and higher odds of mRS 0–2 at 90 days (aOR=1.6, p=0.005) without additional risk of symptomatic hemorrhage (p=0.379). Using a propensity score matched cohort of 490 patients, technique conversion at second attempt increased odds of successful recanalization at second attempt (aOR=1.32, p=0.006) and 90-day mRS 0–2 (aOR=1.38, p=0.008). Conclusions Early conversion to an alternative EVT technique after a failed first pass recanalization in patients with AIS is associated with better technical success and clinical outcomes.

Background and purpose Treatment of recurrent intracranial aneurysms after their initial therapy has been a significant challenge in the field of neurointervention. Recently flow diverters stents are widely used for treating intracranial aneurysms. In this systematic review and meta-analysis, we assessed the safety and efficacy of flow diverter in treating recurrent or recanalized intracranial aneurysms. Methods This meta-analysis is reported following the PRISMA 2020 guidelines. We conducted a systematic review of literature in the PubMed, Embase, Web of Sciences, and Scopus databases. Pooled prevalence and the corresponding 95% are calculated from extracted data using a random-effect model. Results The systematic literature search included 21 studies involving 411 patients, with 135 (32.8%) being male and 276 (67.2%) being females with a total number of 447 aneurysms. The overall rate of adequate occlusion was 90.67% (95% CI: 84.23%–94.65%), and the rates were comparable between the surgery (93.48%), coiling (91.78%), and stenting (85.77%) groups. The overall pooled rate of complete occlusion was 81.80 (95% CI: 71.14%–89.13%). On doing a subgroup analysis, the complete occlusion rates were 89.68%, 84.39%, and 73.47% for the surgery, coiling, and stenting groups, respectively. The overall mortality rate and achieving modified Rankin scale score of 0-2 was 1.28% (95% CI: 0.45%–3.64%) and (95% CI: 89.92%–97.84%), respectively. No significant heterogeneity is noted in the included studies. Conclusion Flow diverter stents are an effective and safe method for retreating recurrent or residual intracranial aneurysms with a high rate of complete and adequate occlusion. The rate of mortality, intracerebral hemorrhage, and overall and procedural complications following using flow diverters for intracranial aneurysms is low.

Background The benefit of intravenous thrombolysis (IVT) is well established. We aim to study the benefits of IVT in acute ischemic stroke (AIS) patients with large vessel occlusion (LVO) who underwent unsuccessful mechanical thrombectomy (MT). Methods We included AIS patients who underwent MT for anterior circulation LVO with failed recanalization (modified treatment in cerebral ischemia [mTICI] score ≤ 2A). Patients who received IVT prior to MT were compared to those who received MT alone. Propensity score matching using demographic, clinical, radiographic and procedural variables was used to match patients with and without IVT. The primary outcome was favorable 90-day good functional outcome (defined as modified Rankin scale of 0–2), and secondary outcomes included intracranial hemorrhage (ICH), symptomatic ICH (sICH), and 90-day mortality. Results Totally, 610 AIS patients with unsuccessful MT were included. After propensity matching, 219 patients were identified in each group. Median age was 70 years and 73 years in the IVT + MT and MT alone groups, respectively. In the IVT + MT group, final mTICI scores of 0, 1, and 2A were achieved in 92 (42.0%), 33 (15.1%), and 94 (42.9%) patients, respectively, versus 76 (34.7%), 29 (13.2%), and 114 (52.1%) in the MT alone group. The IVT + MT group had greater odds of 90-day good functional outcome (adjusted odds ratio 2.54, 95% confidence interval 1.53–4.32). There were no significant differences in secondary outcomes. Conclusions IVT is associated with improved functional outcomes in AIS patients with LVO despite unsuccessful MT.

CSF-venous fistulas (CVFs) are a common cause of spontaneous intracranial hypotension. These fistulas usually occur without any preceding major trauma, surgery, or other iatrogenic cause. Occasionally, patients have a history of minor trauma, though such cases are usually still considered spontaneous. Little is known about predisposing factors that cause patients to develop spontaneous CVFs. Most patients with CVFs have multiple meningeal diverticula on spine imaging, and fistulas usually arise in association with a diverticulum. In the vast majority of cases, the culprit diverticulum from which the CVF arises is atraumatic in origin, presumably on the spectrum of normal variation in spinal anatomy. Here, we present two cases of CVFs that arose in association with posttraumatic pseudomeningoceles. To our knowledge, this phenomenon has not yet been reported, and it potentially represents a novel etiology for CVFs that furthers understanding of their pathogenesis.

Background A combination of intravenous (IVT) or intra-arterial (IAT) thrombolysis with mechanical thrombectomy (MT) for acute ischemic stroke due to large vessel occlusion (AIS-LVO) has been investigated. However, there is limited data on patients who receive both IVT and IAT compared with IVT alone before MT. Methods STAR data from 2013 to 2023 was utilized. We performed propensity score matching between the two groups. The primary outcomes were symptomatic intracranial hemorrhage (sICH) and 90-day modified Rankin Scale (mRS) score 0–2. Secondary outcomes included successful recanalization (modified treatment in cerebral infarction (mTICI) ≥2B, ≥2C), early neurological improvement, any intracranial hemorrhage (ICH), and 90-day mortality. Results A total of 2454 AIS-LVO patients were included. Propensity matching yielded 190 well-matched patients in each group. No significant differences were observed between the groups in either ICH or sICH (odds ratio (OR): 0.80, 95% confidence interval (CI) 0.51–1.24, P=0.37; OR: 0.60, 95% CI 0.29 to 1.24, P=0.21, respectively). Rates of successful recanalization and early neurological improvement (ENI) were significantly lower in MT+IVT + IAT. mRS 0–1 and mortality were not significantly different between the two groups. However, the MT+IVT + IAT group demonstrated superior rates of good functional outcomes (90-day mRS 0–1) compared with patients in the MT+IVT group who had mTICI ≤2B, (OR: 2.18, 95% CI 1.05 to 3.99, P=0.04). Conclusion The combined use of IAT and IVT thrombolysis in AIS-LVO patients undergoing MT is safe. Although the MT+IVT+ IAT group demonstrated lower rates of recanalization and early neurological improvement, long-term functional outcomes were favorable in this group suggesting a potential delayed benefit of IAT.