Hyperacute Perfusion Imaging Before Pediatric Thrombectomy: Analysis of the Save ChildS Study

BACKGROUND AND OBJECTIVES

Perfusion imaging can identify adult patients with salvageable brain tissue who would benefit from thrombectomy in later time windows. The feasibility of obtaining hyperacute perfusion sequences in pediatric stroke is unknown. The aim of this study was to determine whether contrast perfusion imaging delayed time to treatment and to assess perfusion profiles in children with large vessel occlusion stroke.

METHODS

The Save ChildS retrospective cohort study (January 2000-December 2018) enrolled children (1 month-18 years) with stroke who underwent thrombectomy from 27 European and U.S. stroke centers. This secondary analysis included patients with anterior circulation occlusion and available imaging for direct review by the neuroimaging core laboratory. Between-group comparisons were performed using the Wilcoxon rank-sum exact test for continuous variables or Fisher exact test for binary variables. Given the small number of patients, evaluation of perfusion imaging parameters was performed descriptively only.

RESULTS

Of 33 patients with available neuroimaging, 15 (45.4%) underwent perfusion (CT perfusion n = 6; MR perfusion n = 9); all were technically adequate. The median time from onset to recanalization did not differ between groups {4 hours (interquartile range [IQR] 4-7.5) perfusion+; 3.4 hours (IQR 2.5-6.5) perfusion-, p = 0.158}. Target mismatch criteria were met by 10/15 (66.7%) patients and did not correlate with reperfusion status or functional outcome. The hypoperfusion intensity ratio (HIR) was favorable in 11/15 patients and correlated with older age but not NIHSS, time to recanalization, or stroke etiology. Favorable HIR was associated with better functional outcome at 6 months (Pediatric Stroke Outcome Measure 1.0 [IQR 0.5-2.0] vs 2.0 [1.5-3.0], p = 0.026) and modified Rankin Scale 1.0 [0-1] vs 2.0 [1.5-3.5], p = 0.048) in this small sample.

DISCUSSION

Automated perfusion imaging is feasible to obtain acutely in children and does not delay time to recanalization. Larger prospective studies are needed to determine biomarkers of favorable outcome in pediatric ischemic stroke and to establish core and penumbral thresholds in children.

Radiomic features define risk and are linked to DNA methylation attributes in primary CNS lymphoma

Background

The prognostic roles of clinical and laboratory markers have been exploited to model risk in patients with primary CNS lymphoma, but these approaches do not fully explain the observed variation in outcome. To date, neuroimaging or molecular information is not used. The aim of this study was to determine the utility of radiomic features to capture clinically relevant phenotypes, and to link those to molecular profiles for enhanced risk stratification.

Methods

In this retrospective study, we investigated 133 patients across 9 sites in Austria (2005-2018) and an external validation site in South Korea (44 patients, 2013-2016). We used T1-weighted contrast-enhanced MRI and an L1-norm regularized Cox proportional hazard model to derive a radiomic risk score. We integrated radiomic features with DNA methylation profiles using machine learning-based prediction, and validated the most relevant biological associations in tissues and cell lines.

Results

The radiomic risk score, consisting of 20 mostly textural features, was a strong and independent predictor of survival (multivariate hazard ratio = 6.56 [3.64-11.81]) that remained valid in the external validation cohort. Radiomic features captured gene regulatory differences such as in BCL6 binding activity, which was put forth as testable treatment target for a subset of patients.

Conclusions

The radiomic risk score was a robust and complementary predictor of survival and reflected characteristics in underlying DNA methylation patterns. Leveraging imaging phenotypes to assess risk and inform epigenetic treatment targets provides a concept on which to advance prognostic modeling and precision therapy for this aggressive cancer.

Federated learning enables big data for rare cancer boundary detection

Although machine learning (ML) has shown promise across disciplines, out-of-sample generalizability is concerning. This is currently addressed by sharing multi-site data, but such centralization is challenging/infeasible to scale due to various limitations. Federated ML (FL) provides an alternative paradigm for accurate and generalizable ML, by only sharing numerical model updates. Here we present the largest FL study to-date, involving data from 71 sites across 6 continents, to generate an automatic tumor boundary detector for the rare disease of glioblastoma, reporting the largest such dataset in the literature (n = 6, 314). We demonstrate a 33% delineation improvement for the surgically targetable tumor, and 23% for the complete tumor extent, over a publicly trained model. We anticipate our study to: 1) enable more healthcare studies informed by large diverse data, ensuring meaningful results for rare diseases and underrepresented populations, 2) facilitate further analyses for glioblastoma by releasing our consensus model, and 3) demonstrate the FL effectiveness at such scale and task-complexity as a paradigm shift for multi-site collaborations, alleviating the need for data-sharing.

Cerebrovascular Collateral Integrity in Pediatric Large Vessel Occlusion: Analysis of the Save ChildS Study

BACKGROUND AND OBJECTIVES

Robust cerebrovascular collaterals in adult patients with large vessel occlusion stroke have been associated with longer treatment windows, better recanalization rates, and improved outcomes, but the role of collaterals in pediatric stroke is not known. The primary aim was to determine whether favorable collaterals correlated with better radiographic and clinical outcomes in children with ischemic stroke who underwent thrombectomy.

METHODS

This study analyzed a subset of children enrolled in SaveChildS, a retrospective, multicenter, observational cohort study of 73 pediatric patients with stroke who underwent thrombectomy between 2000 and 2018 at 27 US and European centers. Included patients had baseline angiographic imaging and follow-up modified Rankin Scale scores available for review. Posterior circulation occlusions were excluded. Cerebrovascular collaterals were graded on acute neuroimaging by 2 blinded neuroradiologists according to the Tan collateral score, in which favorable collaterals are defined as >50% filling and unfavorable collaterals as <50% filling distal to the occluded vessel. Collateral status was correlated with clinical and neuroimaging characteristics and outcomes. Between-group comparisons were performed with the Wilcoxon rank-sum test for continuous variables or Fisher exact test for binary variables.

RESULTS

Thirty-three children (mean age 10.9 [SD ±4.9]) years were included; 14 (42.4%) had favorable collaterals. Median final stroke volume as a percent of total brain volume (TBV) was significantly lower in patients with favorable collaterals (1.35% [interquartile range (IQR) 1.14%-3.76%] vs 7.86% [IQR 1.54%-11.07%], p = 0.049). Collateral status did not correlate with clinical outcome, infarct growth, or final Alberta Stroke Program Early CT Score (ASPECTS) in our cohort. Patients with favorable collaterals had higher baseline ASPECTS (7 [IQR 6-8] vs 5.5 [4-6], p = 0.006), smaller baseline ischemic volume (1.57% TBV [IQR 1.09%-2.29%] vs 3.42% TBV [IQR 1.26%-5.33%], p = 0.035), and slower early infarct growth rate (2.4 mL/h [IQR 1.5-5.1 mL/h] vs 10.4 mL/h [IQR 3.0-30.7 mL/h], p = 0.028).

DISCUSSION

Favorable collaterals were associated with smaller final stroke burden and slower early infarct growth rate but not with better clinical outcome in our study. Prospective studies are needed to determine the impact of collaterals in childhood stroke.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that in children with ischemic stroke undergoing thrombectomy, favorable collaterals were associated with improved radiographic outcomes but not with better clinical outcomes.

Periprocedural Safety and Feasibility of the New LVIS EVO Device for Stent-Assisted Coiling of Intracranial Aneurysms: An Observational Multicenter Study

BACKGROUND AND PURPOSE

Stent-assisted treatment techniques can be an effective treatment option for intracranial aneurysms. The aim of this study was to evaluate the periprocedural feasibility and safety of the new LVIS EVO stent for the treatment of intracranial aneurysms.

MATERIALS AND METHODS

Patients with intracranial aneurysms treated with the LVIS EVO in 11 European neurovascular centers were retrospectively reviewed. Patient and aneurysm characteristics, procedural parameters, immediate grade of occlusion, and technical and clinical complications were assessed.

RESULTS

Fifty-seven patients with 59 aneurysms were treated with the LVIS EVO device; 57.6% of the aneurysms were incidental; 15.3% were acutely ruptured; 15.3% were recanalized or residual aneurysms; and 11.9% were treated for symptoms other than acute hemorrhage. The most frequent aneurysm locations were the middle cerebral artery (25.4%) and the anterior communicating artery (22.0%). The rate of immediate successful deployment was 93.2%. In 6.8% (n = 4) of cases, additional in-stent angioplasty was needed. The immediate complete occlusion rate was 54.2%, while there was a residual aneurysm in 35.6% and a residual neck in 10.2%. Periprocedural technical complications occurred in 7/59 treatments (11.9%; the most frequent technical complication [n = 3] was thrombus formation), which all resolved completely without clinical sequelae. Postprocedural neurologic complications occurred after 4/59 treatments (6.8%; 2 transient ischemic attacks, 1 minor stroke, 1 major stroke), of which only 1 persistent complication was directly related to the procedure (minor stroke in the vascular territory distal to the stent).

CONCLUSIONS

The LVIS EVO stent is a safe, feasible device for the treatment of intracranial aneurysms.

Feasibility, Safety, and Outcome of Endovascular Recanalization in Childhood Stroke: The Save ChildS Study

Importance

Randomized clinical trials have shown the efficacy of thrombectomy of large intracranial vessel occlusions in adults; however, any association of therapy with clinical outcomes in children is unknown.

Objective

To evaluate the use of endovascular recanalization in pediatric patients with arterial ischemic stroke.

Design, Setting, and Participants

This retrospective, multicenter cohort study, conducted from January 1, 2000, to December 31, 2018, analyzed the databases from 27 stroke centers in Europe and the United States. Included were all pediatric patients (<18 years) with ischemic stroke who underwent endovascular recanalization. Median follow-up time was 16 months.

Exposures

Endovascular recanalization.

Main Outcomes and Measures

The decrease of the Pediatric National Institutes of Health Stroke Scale (PedNIHSS) score from admission to day 7 was the primary outcome (score range: 0 [no deficit] to 34 [maximum deficit]). Secondary clinical outcomes included the modified Rankin scale (mRS) (score range: 0 [no deficit] to 6 [death]) at 6 and 24 months and rate of complications.

Results

Seventy-three children from 27 participating stroke centers were included. Median age was 11.3 years (interquartile range [IQR], 7.0-15.0); 37 patients (51%) were boys, and 36 patients (49%) were girls. Sixty-three children (86%) received treatment for anterior circulation occlusion and 10 patients (14%) received treatment for posterior circulation occlusion; 16 patients (22%) received concomitant intravenous thrombolysis. Neurologic outcome improved from a median PedNIHSS score of 14.0 (IQR, 9.2-20.0) at admission to 4.0 (IQR, 2.0-7.3) at day 7. Median mRS score was 1.0 (IQR, 0-1.6) at 6 months and 1.0 (IQR, 0-1.0) at 24 months. One patient (1%) developed a postinterventional bleeding complication and 4 patients (5%) developed transient peri-interventional vasospasm. The proportion of symptomatic intracerebral hemorrhage events in the HERMES meta-analysis of trials with adults was 2.79 (95% CI, 0.42-6.66) and in Save ChildS was 1.37 (95% CI, 0.03-7.40).

Conclusions and Relevance

The results of this study suggest that the safety profile of thrombectomy in childhood stroke does not differ from the safety profile in randomized clinical trials for adults; most of the treated children had favorable neurologic outcomes. This study may support clinicians' practice of off-label thrombectomy in childhood stroke in the absence of high-level evidence.

Clinical Diffusion Mismatch to Select Pediatric Patients for Embolectomy 6 to 24 Hours After Stroke: An Analysis of the Save ChildS Study

OBJECTIVE

To determine whether thrombectomy is safe in children up to 24 hours after onset of symptoms when selected by mismatch between clinical deficit and infarct.

METHODS

A secondary analysis of the Save ChildS Study (January 2000-December 2018) was performed, including all pediatric patients (<18 years) diagnosed with arterial ischemic stroke who underwent endovascular recanalization at 27 European and United States stroke centers. Patients were included if they had a relevant mismatch between clinical deficit and infarct.

RESULTS

Twenty children with a median age of 10.5 (interquartile range [IQR] 7-14.6) years were included. Of those, 7 were male (35%), and median time from onset to thrombectomy was 9.8 (IQR 7.8-16.2) hours. Neurologic outcome improved from a median Pediatric NIH Stroke Scale score of 12.0 (IQR 8.8-20.3) at admission to 2.0 (IQR 1.2-6.8) at day 7. Median modified Rankin Scale (mRS) score was 1.0 (IQR 0-1.6) at 3 months and 0.0 (IQR 0-1.0) at 24 months. One patient developed transient peri-interventional vasospasm; no other complications were observed. A comparison of the mRS score to the mRS score in the DAWN and DEFUSE 3 trials revealed a higher proportion of good outcomes in the pediatric compared to the adult study population.

CONCLUSIONS

Thrombectomy in pediatric ischemic stroke in an extended time window of up to 24 hours after onset of symptoms seems safe and neurologic outcomes are generally good if patients are selected by a mismatch between clinical deficit and infarct.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that for children with acute ischemic stroke with a mismatch between clinical deficit and infarct size, thrombectomy is safe.

In the borderland of multifocal motor neuropathy and chronic inflammatory demyelinating polyradiculopathy

Chronic inflammatory demyelinating polyradiculopathy (CIDP) and multifocal motor neuropathy (MMN) are seen as distinct entities with marked differences in pathophysiology and clinical, laboratory, and imaging features. We report a patient with an immune-mediated neuropathy in the borderland of CIDP and MMN, whose magnetic resonance imaging and cerebrospinal fluid (CSF) features strongly resembled CIDP, while the clinical course and treatment response suggested the diagnosis of MMN without conduction blocks. There is strong evidence that MMN is not a variant of CIDP and that these conditions can be separated pathologically. Our case report widens the spectrum of MMN presentations, indicating the existence of a clinical overlap syndrome of MMN and CIDP, and emphasizing the need for more precise criteria regarding CSF and nerve root imaging abnormalities in the differentiation of chronic immune-mediated neuropathies.

De novo arteriovenous shunts after endovascular cure of cerebrospinal macro arteriovenous fistulas. A role for the vasa vasorum?

BACKGROUND AND PURPOSE

Macro-arteriovenous fistulas (MAVFs) are arteriovenous shunts draining into a giant venous ectasia. They can be treated by surgery or embolisation. Angiographic controls are usually performed rapidly after treatment in order to prove the cure of the lesion but no long term angiographies are generally scheduled. We wanted to control the stabilities of such lesions at follow-up.

METHOD

Clinical history and imaging of ninety-five patients with high flow shunts draining into venous ectasias (MAVFs, Vein of Galen malformations and dilatations) were reviewed.

RESULTS

De novo arteriovenous shunts related to angiogenesis involving vasa vasorum developed in three patients with MAVFs at various intervals. Genetic underlying conditions as HHT or RASA 1 mutations were suspected in each patient.

CONCLUSIONS

Neo-angiogenesis can occur after cure of MAVFs. Long term imaging follow-ups should be considered as the natural history of such recurrent shunts is currently unknown.

Sex-Specific Differences in Primary CNS Lymphoma

Sex-specific differences have been increasingly recognized in many human diseases including brain cancer, namely glioblastoma. Primary CNS lymphoma (PCNSL) is an exceedingly rare type of brain cancer that tends to have a higher incidence and worse outcomes in male patients. Yet, relatively little is known about the reasons that contribute to these observed sex-specific differences. Using a population-representative cohort of patients with PCNSL with dense magnetic resonance (MR) imaging and digital pathology annotation (n = 74), we performed sex-specific cluster and survival analyses to explore possible associations. We found three prognostically relevant clusters for females and two for males, characterized by differences in (i) patient demographics, (ii) tumor-associated immune response, and (iii) MR imaging phenotypes. Upon a multivariable analysis, an enhanced FoxP3+ lymphocyte-driven immune response was associated with a shorter overall survival particularly in female patients (HR 1.65, p = 0.035), while an increased extent of contrast enhancement emerged as an adverse predictor of outcomes in male patients (HR 1.05, p < 0.01). In conclusion, we found divergent prognostic constellations between female and male patients with PCNSL that suggest differential roles of tumor-associated immune response and MR imaging phenotypes. Our results further underline the importance of continued sex-specific analyses in the field of brain cancer.

Does Device Selection Impact Recanalization Rate and Neurological Outcome?

Background and Purpose—

The recent Save ChildS study provides multicenter evidence for the use of mechanical thrombectomy in children with large vessel occlusion arterial ischemic stroke. However, device selection for thrombectomy may influence rates of recanalization, complications, and neurological outcomes, especially in pediatric patients of different ages. We, therefore, performed additional analyses of the Save ChildS data to investigate a possible association of different thrombectomy techniques and devices with angiographic and clinical outcome parameters.

Methods—

The Save ChildS cohort study (January 2000–December 2018) analyzed data from 27 European and United States stroke centers and included all pediatric patients (<18 years), diagnosed with arterial ischemic stroke who underwent endovascular recanalization. Patients were grouped into first-line contact aspiration (A Direct Aspiration First Pass Technique [ADAPT]) and non-ADAPT groups as well as different stent retriever size groups. Associations with baseline characteristics, recanalization rates (modified Treatment in Cerebral Infarction), complication rates, and neurological outcome parameters (Pediatric National Institutes of Health Stroke Scale after 24 hours and 7 days; modified Rankin Scale and Pediatric Stroke Outcome Measure at discharge, after 6 and 24 months) were investigated.

Results—

Seventy-three patients with a median age of 11.3 years were included. Currently available stent retrievers were used in 59 patients (80.8%), of which 4×20 mm (width×length) was the most frequently chosen size (36 patients =61%). A first-line ADAPT approach was used in 7 patients (9.6%), and 7 patients (9.6%) were treated with first-generation thrombectomy devices. In this study, a first-line ADAPT approach was neither associated with the rate of successful recanalization (ADAPT 85.7% versus 87.5% No ADAPT) nor with the complication rate or the neurological outcome. Moreover, there were no associations of stent retriever sizes with rates of recanalization, complication rates, or outcome parameters.

Conclusions—

Our study suggests that neurological outcomes are generally good regardless of any specific device selection and suggests that it is important to offer thrombectomy in eligible children regardless of technique or device selection.

Registration—

URL: https://www.drks.de/ ; Unique identifier: DRKS00016528.

Spontaneous Intracerebral Hemorrhage Due to Delta Storage Pool Disease in a Patient on a Serotonin-Norepinephrine Reuptake Inhibitor

We report a case of spontaneous intracerebral hemorrhage (sICH) due to delta storage pool disease in a 60-year-old female on a serotonin-norepinephrine reuptake inhibitor (SNRI). Increased susceptibility to SNRI-effects on hemostasis was due to a genetic disposition mediated by a polymorphism of the SLC6A4 gene coding for the human serotonin transporter (SERT). Pathophysiological and clinical implications of these findings are discussed.

Identification of pathogenic YY1AP1 splice variants in siblings with Grange syndrome by whole exome sequencing

Grange syndrome is an autosomal recessive condition characterized by arterial occlusions and hypertension. Syndactyly, brachydactyly, bone fragility, heart defects, and learning disabilities have also been reported. Loss‐of‐function variants in YY1AP1 have only recently been associated with Grange syndrome. YY1AP1 encodes for the transcription coactivator yin yang 1‐associated protein 1 which regulates smooth muscle cell proliferation and differentiation. We here report on three siblings with steno‐occlusive arterial disorder and syndactyly in two of them. Whole exome sequencing including near‐splice regions led to the identification of two intronic YY1AP1 variants which were predicted to interfere with normal splicing. Sanger sequencing demonstrated compound‐heterozygosity in all affected siblings. RT‐PCR analyses confirmed skipping of exon 6 on one allele and exonization of 22 bp in intron 6 on the other. This is the first report of biallelic YY1AP1 variants in noncoding regions and just the second family with multiple affected siblings. Therefore, our report further delineates the phenotypic spectrum of Grange syndrome.

The Neuroform Atlas stent to assist coil embolization of intracranial aneurysms: a multicentre experience

Objective

To assess the clinical safety and efficacy of the Atlas microstent in stent-assisted coil embolization of wide-necked intracranial aneurysms.

Methods

Single-center observational study in 36 patients (24 female, 12 male, mean age 56 years) with 37 aneurysms for the endovascular treatment of wide-necked aneurysms. After giving informed consent, patients were included according to the following criteria: aneurysm dome-to-neck ratio <2 or neck diameter >4 mm, and a parent vessel diameter of ≤4.5 mm. Primary endpoint for clinical safety was absence of death, absence of major or minor stroke, and absence of transient ischemic attack. Primary endpoint for treatment efficacy was complete angiographic occlusion according to the Raymond-Roy occlusion classification (RROC) immediately after the procedure.

Results

In 36/37 (97%) cases, the primary endpoint of safety was reached, one patient had a transitory ischemic attack which completely resolved until discharge. In 31/37 (84%) cases, complete occlusion (RROC 1) was reached, and in 6/36 (17%), a residual neck remained (RROC 2). A sequential approach (first stent, then coiling through the same catheter) was used in 21 cases; the other 16 were treated with the jailing technique. Deployment was technically successful in all cases. Follow-up at a median of 6.1 months was available for 29/37 (78%) aneurysms and showed complete occlusion in 27/29 aneurysms (93%) and a neck remnant in 2 cases (7%).

Conclusion

Deployment of the Neuroform Atlas microstent is a safe and effective method for the treatment of intracranial wide-necked aneurysms.

European Multicenter Study for the Evaluation of a Dual-Layer Flow-Diverting Stent for Treatment of Wide-Neck Intracranial Aneurysms: The European Flow-Redirection Intraluminal Device Study

BACKGROUND AND PURPOSE

Endoluminal reconstruction with flow-diverting stents represents a widely accepted technique for the treatment of complex intracranial aneurysms. This European registry study analyzed the initial experience of 15 neurovascular centers with the Flow-Redirection Intraluminal Device (FRED) system.

MATERIALS AND METHODS

Consecutive patients with intracranial aneurysms treated with the FRED between February 2012 and March 2015 were retrospectively reviewed. Complications and adverse events, transient and permanent morbidity, mortality, and occlusion rates were evaluated.

RESULTS

During the defined study period, 579 aneurysms in 531 patients (median age, 54 years; range, 13-86 years) were treated with the FRED. Seven percent of patients were treated in the acute phase (≤3 days) of aneurysm rupture. The median aneurysm size was 7.6 mm (range, 1-36.6 mm), and the median neck size 4.5 mm (range, 1-30 mm). Angiographic follow-up of >3 months was available for 516 (89.1%) aneurysms. There was progressive occlusion witnessed with time, with complete occlusion in 18 (20%) aneurysms followed for up to 90 ± 14 days, 141 (82.5%) for 180 ± 20 days, 116 (91.3%) for 1 year ± 24 days, and 122 (95.3%) aneurysms followed for >1 year. Transient and permanent morbidity occurred in 3.2% and 0.8% of procedures, respectively. The overall mortality rate was 1.5%.

CONCLUSIONS

This retrospective study in real-world patients demonstrated the safety and efficacy of the FRED for the treatment of intracranial aneurysms. In most cases, treatment with a single FRED resulted in complete angiographic occlusion at 1 year.

Safety of endovascular treatment in acute stroke patients taking oral anticoagulants

Background

The endovascular treatment of acute cerebral ischemia has been proven beneficial without major safety concerns. To date, the role of endovascular treatment in patients treated with oral anticoagulants, which may be associated with periprocedural intracranial bleeding, remains uncertain.

Aims

The objective of the current analysis is to evaluate the safety of endovascular treatment in patients treated with oral anticoagulants.

Methods

The ENDOSTROKE-Registry is a commercially independent, prospective observational study in 12 stroke centers in Germany and Austria collecting pre-specified variables about endovascular stroke therapy.

Results

Data from 815 patients (median age 70 (interquartile range (IQR) 20), 57% male) undergoing endovascular treatment with known anticoagulation status were analyzed. A total of 85 (median age 76 (IQR 8), 52% male) patients (10.4%) took vitamin-K-antagonists prior to endovascular treatment. Anticoagulation status as measured with international normalized ratio was above 2.0 in 31 patients. Intracranial hemorrhage occurred in 11.8% of patients taking vitamin-K-antagonists compared to no-vitamin-K-antagonists (12.2%, p = 0.909). After adjustment for confounding factors which were unbalanced at univariate level such as NIHSS and age, anticoagulation status was not found to significantly influence clinical outcome (modified Rankin Scale 3–6) and occurrence of intracranial hemorrhage in a multivariate logistic regression analysis.

Conclusion

Prior use of vitamin-K-antagonists was not associated with a higher rate of periprocedural intracranial hemorrhage after endovascular treatment or worse outcome. Endovascular treatment should be considered as an important treatment option in patients taking vitamin-K-antagonists.

Endovascular stroke therapy in Austria: a nationwide 1-year experience

BACKGROUND AND PURPOSE

Based on a tight network of stroke units (SUs) and interventional centres, endovascular treatment of acute major intracranial vessel occlusion has been widely implemented in Austria. Documentation of all patients in the nationwide SU registry has thereby become mandatory.

METHODS

Demographic, clinical and interventional characteristics of patients who underwent endovascular treatment for acute ischaemic stroke in 11 Austrian interventional centres between 1 October 2013 and 30 September 2014 were analysed.

RESULTS

In total, 301 patients (50.5% women; median age 70.5 years; median National Institutes of Health Stroke Scale score 17) were identified.193 patients (64.1%) additionally received intravenous thrombolysis. The most frequent vessel occlusion sites were the M1 segment of the middle cerebral artery (n = 161, 53.5%), the intracranial internal carotid artery (n = 60, 19.9%) and the basilar artery (n = 40, 13.3%). Stent retrievers were used in 235 patients (78.1%) and adequate reperfusion (modified Thrombolysis in Cerebral Infarction scores 2b and 3, median onset to reperfusion time 254 min) was achieved in 242 patients (81.4%). Symptomatic intracranial haemorrhage occurred in 7%. 43.8% of patients (n = 132) had good functional outcome (modified Rankin Scale score 0-2) and the mortality rate was 20.9% (n = 63) after 3 months. Compared to the anterior circulation, vertebrobasilar stroke patients had higher mortality. Patients with secondary hospital transportation had better outcomes after 3 months than in-house treated patients.

CONCLUSION

Our results document nationwide favourable outcome and safety rates of endovascular stroke treatment comparable to recent randomized trials. The ability to provide such data and the need to further optimize such an approach also underscore the contribution of respective registries.

Abstract TP9: Safety of Endovascular Treatment in Acute Stroke Patients Taking Oral Anticoagulants

Introduction: The endovascular treatment (EVT) of cerebral ischemia in the case of large vessel occlusion has been established over recent years. Randomized trials showed a positive impact on the clinical outcome of endovascular treatment in addition to thrombolysis with respect to clinical outcome and safety, so that this therapeutic option will be implemented in future guidelines. The role of EVT in patients treated with oral anticoagulants remains uncertain.

Hypothesis: We assessed the hypothesis that application of EVT is safe with regard to the occurrence of intracranial bleeding and clinical outcome in patients taking anticoagulants.

Methods: The ENDOSTROKE-Registry is a commercially independent, prospective observational study in 12 stroke centers in Germany and Austria launched in January 2011. An online tool served for data acquisition of pre-specified variables concerning endovascular stroke therapy.

Results: Data from 815 patients (median age 70, 57% male) undergoing EVT and known anticoagulation status were analyzed. A total of 85 (median age 76, 52% male) patients (10.4%) took oral anticoagulants prior to EVT. Anticoagulation status as measured with INR was 2.0-3.0 in 24 patients (29%), <2.0 in 52 patients (63%) and above 3.0 in 7 patients (8%) of 83 patients with valid INR data prior to EVT. Patients taking anticoagulants were significantly older (median age 76 vs. 69, p < 0.001). Comparing those patients taking anticoagulants and those not, there were no differences concerning NIHSS at admission (with anticoagulants Median-NIHSS 17 vs. without Median-NIHSS 15, p = 0.492, Mann Whitney Test) and the rate of intracranial hemorrhage after intervention (with anticoagulants 11.8% vs. without 12.2%, p = 0.538). After adjustment for age and NIHSS at admission there were no significant differences between the two groups with regard to good clinical outcome, as measured with the modified ranking scale (mRS, 90d-mRS 0-2, 39.2% of patients not receiving anticoagulants; 25.9% of those receiving anticoagulants).

Conclusion: The application of endovascular treatment in patients taking oral anticoagulants is safe and should be considered in acute stroke treatment as an important alternative to contraindicated intravenous thrombolysis.

Abstract 105: Time for Collaterals? Evidence from 695 Endovascular Therapy Cases for Acute Stroke in ENDOSTROKE

Background: Recent stroke clinical trials demonstrate the profound impact of collaterals, yet time constraints are often cited as rationale for not evaluating or imaging collaterals prior to endovascular therapy (EVT). We examined the role of collaterals on patient outcomes in a large registry of EVT, analyzing actual time required to obtain such data before treatment of various occlusion sites and monitoring for potential harm.

Methods: ENDOSTROKE is an industry-independent, centrally-monitored multicenter registry evaluating EVT in routine clinical practice. Central reading of angiographic data blinded to clinical information was performed by the core lab in 695 patients assessing TICI scores, ASITN collateral grade and detailed procedural time metrics.

Results: 75% had anterior circulation strokes (including 270 proximal MCA, 106 ICAT, 90 cICA occlusions) and 25% posterior circulation strokes (including 148 basilar artery occlusions). Assessment of ASITN collateral grade was possible in 511 (73%) of patients; in 184 (27%) collateral status was not obtained prior to therapeutic intervention. Median time from initial angiography and first evidence of TICI 2A reperfusion was only one minute longer in patients with available ASITN scores than in those without (38 min (23, 61) vs. 37 (22, 55), p=0.552) and time-differences were even smaller in anterior circulation strokes (median time 37 min in both groups). In vertebrobasilar occlusion, this time metric was 5 minutes longer in those with available ASITN scores (39 min (24, 39)) than in those without (34 min (23, 52), p=0.357). Of those with ASITN available, patients with grade 3-4 had much better outcomes (48% 0-2 90-day mRS) than patients with grade 0-2 (30%, p<0.0001). No excess in complication rate (i.e. dissection, thrombemboli) was noted in the cohort with available ASITN.

Conclusions: Collaterals have a dramatic association with clinical outcomes in the largest endovascular study to date. In routine practice, EVT outcomes across various occlusion sites are strongly influenced by collateral grade. Negligible time of only a few minutes is typically required to obtain such essential data prior to treatment with no cost of incremental harm.

In-hospital complication rates after stent treatment of 388 symptomatic intracranial stenoses: results from the INTRASTENT multicentric registry

BACKGROUND AND PURPOSE

Stenting is increasingly used as an adjunct to medical therapy in symptomatic intracranial stenoses. High periprocedural adverse event rates are one of the limitations of endovascular treatment. Data from the INTRASTENT multicentric registry should demonstrate in-hospital complications at the current stage of clinical development of the stent procedure.

METHODS

Participating centers entered the records of all their consecutive intracranial stent procedures into the database. To determine the clinical outcome in the acute phase, we distinguished transient ischemic attack/nondisabling stroke (modified Rankin Scale <2), disabling stroke, death, and intracranial hemorrhage as clinical complications and analyzed whether they were associated with patient- or stenosis-related risk factors.

RESULTS

Data from 372 patients with 388 stenoses proved 4.8% disabling strokes and 2.2% deaths. Transient or minor events were detected in 5.4% of the cases. Hemorrhagic events (3.5%) occurred more frequently after treatment of middle cerebral artery stenoses (P=0.004) and were associated with significantly higher morbidity and mortality rates. Ischemic strokes by compromise of perforating branches were detected mainly in the posterior circulation. However, the overall rate of severe adverse events was not dependent from location, degree, and morphology of the stenosis or from patient's age, gender, vascular risk factors, or type of qualifying event.

CONCLUSIONS

The complication rates within the registry are within the limits of previously published data. Severe adverse events were equally distributed between potential risk groups with similar rates but different types of main complications in the anterior and posterior circulation.

Postprocedural high-density lipoprotein cholesterol predicts carotid stent patency at 1 year

The durability of carotid artery stenting (CAS) is affected by the occurrence of myointimal proliferation and in-stent restenosis (ISR). We aimed to identify clinical, angiographic, and laboratory predictors of ISR, paying special attention to postprocedural metabolic factors. A total of 102 consecutive patients with successful CAS for > or =70% atherosclerotic internal carotid artery stenosis were followed up with neurological assessment and duplex sonography 1 day, 1 month, and 1 year after CAS. Lipid profile and hemoglobin A(1c) were tested at the 1-month follow-up visit. Ten (10%) patients had ISR > or =50% after 1 year. Compared with patients without ISR (n = 92), patients with ISR were more often current smokers (33% vs. 70%, P = 0.034) and had significantly lower 1-month high-density lipoprotein (HDL) cholesterol: median (range) 47 (24-95) mg/dl vs. 39.5 (25-50) mg/dl, P = 0.031. Multivariate logistic regression analyses identified 1-month HDL cholesterol >45 mg/dl as the only independent predictor of carotid stent patency at 1 year (P = 0.033, OR = 0.09, 95% CI 0.01-0.83). Postprocedural HDL cholesterol levels predict carotid stent patency at 1 year. With the possibility of elevation of HDL cholesterol by lifestyle changes and medication, this finding may have implications for the future management of patients undergoing CAS.

Does carotid stent cell design matter?

BACKGROUND AND PURPOSE

Carotid stent cell design has recently been suggested to be a determinant of periprocedural and early postprocedural neurologic complications. We investigated the impact of closed- versus open-cell stent design on neurologic adverse events and mortality after carotid artery stenting.

METHODS

We studied 1684 consecutive patients (1010 asymptomatic, 674 symptomatic) from 10 European centers who underwent carotid artery stenting with either closed-cell (n=859, 51%) or open-cell (n=825, 49%) design stents. Rates of transient ischemic attack, stroke, and death on the day of the procedure (acute events) and from day 1 to day 30 after the procedure (subacute events) were analyzed (95% CIs).

RESULTS

Combined transient ischemic attack, stroke, or death rates, and stroke or death rates within 30 days of treatment were 6.1% (95% CI, 5.0 to 7.2) and 3.1% (95% CI, 2.3 to 3.9) for the closed-cell design versus 4.1% (95% CI, 3.2 to 5.0) and 2.4% (95% CI, 1.7 to 3.1) for the open-cell design stents (P=0.077, P=0.38), respectively, without significant differences in asymptomatic and symptomatic patients. By propensity-score-adjusted multivariable analysis, the open-cell carotid stent design was not associated with a differential risk for combined acute and subacute neurologic complications compared with closed-cell stents (adjusted odds ratio=0.84, P=0.53). When analyzed separately, the risk for acute events on the day of the procedure (adjusted odds ratio=0.83, P=0.57) and the risk for subacute events at days 1 to 30 (adjusted odds ratio=1.61, P=0.51) also were not significantly different between the groups.

CONCLUSIONS

Current data do not support the superiority of a specific carotid stent cell design with respect to neurologic complications, stroke, and mortality risk.

Bleeding risk analysis in stroke imaging before thromboLysis (BRASIL): pooled analysis of T2*-weighted magnetic resonance imaging data from 570 patients

BACKGROUND AND PURPOSE

There has been speculation that the risk of secondary symptomatic intracranial hemorrhage (SICH) may be increased after thrombolytic therapy in ischemic stroke patients who have cerebral microbleeds (CMBs) on T2*-weighted magnetic resonance imaging. Because of this concern, some centers withhold potentially beneficial thrombolytic therapy from these patients.

METHODS

We analyzed magnetic resonance imaging data acquired within 6 hours after symptom onset from 570 ischemic stroke patients treated with intravenous tissue plasminogen activator in 13 centers in Europe, North America, and Asia. Baseline T2*-weighted magnetic resonance images were evaluated for the presence of CMBs. The primary end point was SICH, defined as clinical deterioration with an increase in the National Institutes of Health Stroke Scale score by >or=4 points, temporally related to a parenchymal hematoma on follow-up-imaging.

RESULTS

A total of 242 CMBs were detected in 86 of 570 patients (15.1%). The number of CMBs ranged from 1 to 77 in the individual patient, with >or=5 CMBs in 6 of 570 patients (1.1%). Proportions of patients with SICH were 5.8% (95% CI, 1.9 to 13.0) in the presence of CMBs and 2.7% (95% CI, 1.4 to 4.5) in patients without CMBs (P=0.170, Fisher's exact test), resulting in no significant absolute increase in the risk of SICH of 3.1% (95% CI, -2.0 to 8.3).

CONCLUSIONS

The data suggest that if there is any increased risk of SICH attributable to CMBs, it is likely to be small and unlikely to exceed the benefits of thrombolytic therapy. No reliable conclusion regarding risk in the rare patient with multiple CMBs can be reached.

Surgical management of an ACM aneurysm eight years after coiling

The authors present a case report on rebleeding of a medial cerebral aneurysm (MCA) eight years after complete endovascular coiling. The primarily successfully coiled MCA aneurysm showed a local regrowth which, however, was not the source of the rebleeding. The angiogram demonstrated no evidence of contrast filling of the coiled segment, but according to intraoperative findings (haematoma location, displacement of coils, evident place of rupture) there is no doubt that the coiled segment of the aneurysm was responsible for the haemorrhage.

Timing of stenting of symptomatic carotid stenosis is predictive of 30-day outcome

For patients with symptomatic carotid stenosis, benefit from carotid artery stenting (CAS) highly depends on the 30-day stroke and death rates. Identification of predictors of unfavourable outcome would help guide the patient selection. We analysed the influence of clinical and angiographic factors on the 30-day outcomes of 77 consecutive patients who underwent CAS for > or = 60% symptomatic carotid stenosis within 180 days of transient ischaemic attack or moderate stroke (modified Rankin Scale score < or = 3). The 30-day composite end-point for stroke (7.8%) and death of any cause (1.3%) was 9.1%. Patients with complicated CAS were older than patients with uncomplicated CAS (mean age 75.1 +/- 8.2 vs. 65.9 +/- 9.5 years, P = 0.015) and underwent stenting significantly earlier after the qualifying event: median delay 1.5 weeks (range: 0.2-3.0) vs. 3.2 weeks (range: 0.5-26), P = 0.004. In multivariate logistic regression analyses, age [odds ratio (OR) = 1.148; 95% confidence interval (CI): 1.011-1.304 and P = 0.033] and delay of treatment < 2 weeks (OR = 22.399; 95% CI: 2.245-223.445 and P = 0.008) remained the only variables significantly associated with 30-day outcome. CAS carries a considerable risk in old patients and when performed early (< 2 weeks) after the qualifying event. Future reports should address the timing of CAS.

[Intracerebrally localized sarcoma NOS--an interdisciplinary challenge]

BACKGROUND

In the literature, surveys of malignant intracerebral nerve sheath tumors are very rare (Table 1). Therapeutic guidelines do not exist.

CASE REPORT

A 28-year-old female patient presented with a tumor in the postcentral region of the left parietal lobe (Figures 1 and 2). The specimen could not be categorized into a common tumor entity and was classified as sarcoma NOS. Shortly after surgery, a recurrence occurred (Figures 3 to 5) followed by a further excision. Due to the rapid tumor growth irradiation with CT-aided treatment planning (Figure 6) has been started immediately afterwards. A dose of 5,400 cGy in 22 fractions was administered.

RESULT

2 weeks after treatment, the patient presented with a noticeable tumor regression (magnetic resonance imaging; Figures 7 to 9). She developed pulmonary metastases. A partial remission could be achieved by systemic chemotherapy. Unfortunately, the patient died because of an exacerbation of a hepatic encephalopathy.

CONCLUSION

In cases of intracerebrally localized sarcomas NOS, the earliest possible start of radiotherapy after surgery seems useful because of the noticed radiosensitivity of these tumors. In regard of the local control, this tumor entity shows a documented excellent response to radiotherapy. Expectedly, distant metastases cannot be influenced. Interdisciplinary cooperation is mandatory to enhance the diagnostic process, the treatment decisions, and the results.

Cyanide-induced akinetic rigid syndrome: Clinical, MRI, FDG-PET, β-CIT and HMPAO SPECT findings

A 35-year-old female ingested a lethal dose of potassium cyanide in a suicide attempt. She survived following antidote therapy and intensive care. Following artificial coma she presented with an agitative state for several days followed by akinetic mutism, buccofacial and ideomotoric aphasia. Severe rigid-akinetic syndrome, dysarthria, dysphagia and generalized dystonia developed weeks later. MRI revealed lesions in the caudate and lentiform nuclei, precentral cortex, and cerebellum. SPECT by [123-I] 2 beta-carbomethoxy-3-beta-(4-iodophenyl)-Tropan on two occasions revealed progressive loss of dopamine transporter suggestive of nigral neuronal apoptosis. Striatal and frontal hypometabolism and hypoperfusion were found by FDG-PET and HMPAO SPECT.

Prospective study on cranioplasty with individual carbon fiber reinforced polymer (CFRP) implants produced by means of stereolithography

BACKGROUND

The aim of this study was to evaluate the value of carbon fiber reinforced polymer (CFRP) cranial implants produced by means of 3-dimensional (3D) stereolithography (SL) and template modeling for reconstructions of complex or extensive cranial defects.

PATIENTS

A series of 41 cranioplasties with individual CFRP implants was performed in 37 patients between April 1996 and November 2002. Only patients with complex and/or large cranial defects were included, most of them having extended scarring or dural calcification and poor quality of the overlying soft-tissue cover after infection or multiple preceding operations. Involvement of frontal sinus, a known risk factor for complications after cranioplasty, was the case in 21 patients (51.2%).

METHODS

A computer-based 3D model of the skull with the bony defect was generated by means of stereolithography after acquisition, evaluation and transfer of the patient's helical computed tomography (CT) data. A wax template of the defect that was used to design the individual prosthesis-shape was invested in dental stone. Then, the cranial implant was fabricated out of CFRP by loosen mold.

RESULTS

Reconstruction of defects measuring up to 17 x 9 cm was performed. The intra-operative fit of the implants was excellent in 36 (87.8%), good in 1 (2.4%), and fair in 4 (9.8%) of the cases. Problems of implant fit occurred because of extended scarring and poor quality of soft-tissue cover. Adverse reactions were observed in 5 patients (1 subdural, 1 subcutaneous hematoma, 2 infections, 1 allergic reaction). Excellent contours and a solid stable reconstruction have been maintained in 30 out of 35 remaining plates (mean follow-up 3.6 years). No adverse effects concerning postoperative imaging, the accuracy of electroencephalograms and radiation therapy have been observed.

CONCLUSIONS

The authors believe that this relatively new technique represents an advance in the management of complex and large cranial defects, but seems less suitable for simple defects because of cost-intensive techniques. Because of the high mechanical strength, biocompatibility, innovative design, and especially radiolucency, CFRP implants should, however, be considered in smaller defects if further imaging investigations or irradiation therapies are necessary.

Cerebrovascular stereolithographic biomodeling for aneurysm surgery

✓ Stereolithographic (SL) biomodeling is a new technology that allows three-dimensional (3D) imaging data to be used in the manufacture of accurate solid plastic replicas of anatomical structures. The authors describe their experience with a patient series in which this relatively new visualization method was used in surgery for cerebral aneurysms.

Using the rapid prototyping technology of stereolithography, 13 solid anatomical biomodels of cerebral aneurysms with parent and surrounding vessels were manufactured based on 3D computerized tomography scans (three cases) or 3D rotational angiography (10 cases). The biomodels were used for diagnosis, operative planning, surgical simulation, instruction for less experienced neurosurgeons, and patient education. The correspondence between the biomodel and the intraoperative findings was verified in every case by comparison with the intraoperative video. The utility of the biomodels was judged by three experienced and two less experienced neurosurgeons specializing in microsurgery.

A prospective comparison of SL biomodels with intraoperative findings proved that the biomodels replicated the anatomical structures precisely. Even the first models, which were rather rough, corresponded to the intraoperative findings. Advances in imaging resolution and postprocessing methods helped overcome the initial limitations of the image threshold. The major advantage of this technology is that the surgeon can closely study complex cerebrovascular anatomy from any perspective by using a haptic, “real reality” biomodel, which can be held, allowing simulation of intraoperative situations and anticipation of surgical challenges. One drawback of SL biomodeling is the time it takes for the model to be manufactured and delivered. Another is that the synthetic resin of the biomodel is too rigid to use in dissecting exercises. Further development and refinement of the method is necessary before the model can demonstrate a mural thrombus or calcification or the relationship of the aneurysm to nonvascular structures.

This series of 3D SL biomodels demonstrates the feasibility and clinical utility of this new visualization medium for cerebrovascular surgery. This medium, which elicits the intuitive imagination of the surgeon, can be effectively added to conventional imaging techniques. Overcoming the present limitations posed by material properties, visualization of intramural particularities, and representation of the relationship of the lesion to parenchymal and skeletal structures are the focus in an ongoing trial.