Diagnostic delay in Hidradenitis suppurativa investigated using data from social media and from statutory health insurances

BACKGROUND

The chronic inflammatory skin disease hidradenitis suppurativa (HS) leads to severe pain and reduced quality of life. Nonetheless, it often takes years until a correct diagnosis is made. In this analysis, disease-related experiences and pathways of patients with HS were investigated and compared with the physicians' perspective.

METHODS

Public posts on forums and social media as well as results of a survey conducted among dermatologists and their patients on the actual medical care reality of HS in Germany were analysed. Furthermore, claims data from German health insurance companies were evaluated.

RESULTS

Patients with HS suffer from a 43.3% reduction in working ability. Dermatology (26.5%) was the most frequently consulted specialty, with HS diagnosed predominantly in the inpatient setting (43.8%). Abscesses were described as the most frequent alternative diagnosis in HS patients (53.2%). Patient-reported changes of physicians in dermatology (34.1%) and surgery (42.4%) occurred predominantly within the specialty. Dermatology received most referrals from general practitioners (67.1%), but only 12.1% from surgeons.

CONCLUSION

There is an urgent need to reduce the delay in diagnosis and the prolonged burden of disease in patients with HS. Therefore, awareness of the disease, its detection and treatment which goes beyond dermatology should be promoted, if possible as part of medical studies.

Data on Ocrelizumab Treatment Collected by MS Patients in Germany Using Brisa App

BACKGROUND

With a rising number of multiple sclerosis (MS) cases and increasing pressure on health systems, digital companion apps like Brisa, designed specifically for people with MS, can play an important role in the patient journey. These apps enable the collection of real-time longitudinal data that are critical to our understanding of the pathophysiology and progression of MS.

METHODS

This retrospective, descriptive analysis consists of data from Brisa users who registered between 6 August 2021 and 8 September 2022. Of the unique users, 37.7% (n = 1593) fulfilled the inclusion criteria including information about medication and demographics and tracked one or more symptoms and/or patient-reported outcomes. Users were classified as moderate-efficacy treatment users, high-efficacy treatment users and ocrelizumab users, and the reporting frequency and scores of symptoms and patient-reported outcomes were analyzed.

RESULTS

The largest cohort of Brisa users (405) reported treatment with ocrelizumab and were mostly diagnosed 2-5 years before the survey. The most reported MS symptoms were similar between OUs (ocrelizumab users), HETUs (high-efficacy treatment users) and METUs (moderate-efficacy treatment users). OUs on average reported symptoms and answered questionnaires more frequently. Baseline scores between HETUs and OUs were similar, whereas baseline scores of METUs were slightly lower in comparison. In a further analysis of OUs, disability scores increased with age; users aged 26-45 years had higher pain scores than 18-25-year-olds. No significant differences were found in quality of life, bowel control and vision between age groups.

CONCLUSION

These findings show that the characteristics of the Brisa cohort are similar to the results of other studies and registries and can provide a representative overview of everyday disease management. Thereby, these results can bridge the gap between clinical research and real patient experience, but they also raise new questions, such as how often the hard-and-early therapy approach is already used and whether baseline characteristics and reasons for choosing a particular treatment contribute to the different outcomes over time. Answering these questions requires further research and analysis.

Shifting from the treat-to-target to the early highly effective treatment approach in patients with multiple sclerosis - real-world evidence from Germany

Background

While evidence highlights the effectiveness of initiating disease-modifying therapy with a high-efficacy medication for multiple sclerosis (MS) patients with poor prognostic factors, it remains unclear whether this approach has been adopted by a broad range of MS providers in Germany yet.

Objective

To assess the adoption of the early highly effective treatment (EHT) compared to the treat-to-target treatment approach with the option of escalating treatment efficacy over time in Germany based on real-world evidence data.

Design

Patient-level pharmacy dispensing data from the Permea platform were analysed from 2020 to 2022.

Methods

In total, 29,529 therapy beginners (>18 years) were included to analyse shifts in treatment approaches over time and switching behaviour. Medication classification adhered to the German Society of Neurology guidelines and designated fumarates, glatiramer acetate, teriflunomide and interferons as low-efficacy category 1 medications; cladribine and S1P-modulators as medium-efficacy category 2 medications; and alemtuzumab, natalizumab, ocrelizumab, ofatumumab and rituximab (off-label) as high-efficacy category 3 medications.

Results

Our results show that 70.0% of patients redeemed their first prescription for category 1 medication, 16.3% for category 2 and 13.7% for category 3 medications. The proportion of prescriptions filled shifted from 2020 to 2022 with a decrease of 14.7% for category 1 drugs and an increase of 12.5% for category 3 drugs. 93.2% of patients stayed on their initially prescribed medication category. 3.2% of category 1 and 3.7% of category 2 therapy beginners escalated to category 3 medication. 3.4% of category 3 medication users de-escalated their treatment to category 1 or category 2.

Conclusion

While most individuals started their treatment according to the treat-to-target approach and remained on their initially prescribed medication category, there has been a steadily increasing shift towards the EHT approach since 2020. These insights demonstrate that, while not officially recommended by German guidelines, MS providers increasingly adopt the EHT approach.

The IMPACT of the COVID-19 Pandemic on Prescription Drug Use in Patients with Psoriasis Vulgaris in Germany

INTRODUCTION

Real-world evidence (RWE) data is increasingly important to generate rapid insights to effectively manage patient populations. Disruptions like the coronavirus disease 2019 (COVID-19) pandemic may negatively impact the choice of medications used for managing chronic diseases such as psoriasis (PSO). Here, we explored the effect of the COVID-19 pandemic on the sales volumes of treatment guideline-based PSO medication in Germany.

METHODS

Patient-level pharmacy dispensing data from the Permea platform, covering approximately 44% of all community pharmacy dispensing in Germany, were analysed from 2019 through to 2021. Patient demographics and PSO indicated medication sales were assessed specifically before and during the pandemic in Germany.

RESULTS

We included 6,865,852 sold PSO related drugs from April 2019 to March 2021. Medication sales increased during the pandemic compared with before the pandemic for treatment classes of first-line biological and second-line drugs. The increase was observed across all age groups, but monthly variations could not be detected. Furthermore, we observed increased sales in first-line biological and second-line medications when comparing low to high COVID-19 incidence state.

CONCLUSION

Throughout the COVID-19 pandemic the PSO indicated medication sales increased for first-line biological and second-line treatment. This shows that despite the pandemic impact, there continues to be an increase in sales volume for biologics. Only German federal states with intermittently very high COVID-19 incidences show a stagnation in sales volume. The reasons for this need to be investigated in further studies to possibly gain a better understanding of the concerns and uncertainties of patients with PSO.

Drug switching in axial spondyloarthritis patients in Germany - a social listening analysis

Background

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease which primarily affects the axial skeleton resulting in chronic back pain and stiffness. According to the guideline, the first-line treatment includes non-steroidal anti-inflammatory drugs (NSAIDs), conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and non-pharmacological treatment. Second line treatment involves biological disease-modifying antirheumatic drugs (bDMARDs) such as tumour necrosis factor and interleukin-17 inhibitors.

Objectives

The aim of this social media listening research project was to analyse switches of medication and the reasons thereof to gain valuable insights into real-life journeys of patients suffering from axSpA.

Methods

Publicly available posts in German-speaking disease-specific forums were scanned for disease-specific keywords and commonly used drugs by axSpA patients on the Permea platform. Posts containing at least two key words were selected and switches between medications were manually labelled. A total of 287 scraped posts between 01 July 2010 and 04 Feb 2022 were analysed.

Results

The largest group of described medication switches was initially using bDMARDs. Switches to a different bDMARD, termination of medication and switches to glucocorticoids were most frequently named. Patients on NSAIDs switched to glucocorticoids, a different NSAID or bDMARD, whereas patients on csDMARDs most frequently changed to bDMARDs. In all medication groups the main reason for switching was insufficient efficacy and side effects. Additionally, for the medication groups bDMARDs, csDMARDs and corticosteroids, pregnancy and lactation were given as a reason for switching, whereas patients in the NSAID group never mentioned pregnancy and breastfeeding as a reason for switching treatment.

Conclusion

Our analysis shows medication switches based on real-life patient experiences shared with peers in a social listening setting. We also show medication switches differing from advised guidelines. Gathering real-life insights into patients' journey dealing with chronic diseases allows us to understand, and thereby improve patient care and treatment.

Outcome and risk of hemorrhage in patients with tandem lesions after endovascular treatment: A propensity score-matched case-control study

Objectives

Endovascular treatment of acute stroke patients with large vessel occlusions is well established. But tandem lesions of the internal carotid artery and the intracranial anterior circulation remain a challenge regarding the technical conditions and the putative higher risk of hemorrhage due to often required antiplatelet therapy.This study aims to evaluate the clinical outcome and the risk of hemorrhage after endovascular treatment of tandem lesions, with special regard to the periprocedural antiplatelet regimen.

Materials and Methods

In this retrospective study, we included 63 consecutive stroke patients with endovascular treated tandem lesions. One hundred eleven patients with a solitary intracranial occlusion were matched using a "propensity score-matched analysis" with the covariates sex, age, wake-up stroke, iv-thrombolysis and NIHSS.

Results

Rates of successful recanalization (mTICI 2b/3) and periprocedural complications were equal in both groups (P = 0.19; P = 0.35). The rate of good clinical outcome (mRS≤2) was similar, and the incidence of symptomatic hemorrhages was not significantly different (7.9% tandem lesions vs. 5.4% isolated intracranial occlusion, P = 0.51). Even intensified antiplatelet therapy in patients with tandem lesions did not increase the rate of symptomatic intracranial hemorrhages (P = 0.87).

Conclusions

Clinical outcome and symptomatic intracranial hemorrhages did not differ significantly between endovascular treated patients with tandem lesions and matched patients with solitary intracranial occlusions, regardless of the antiplatelet regimen. Therefore, the complex technical requirements for recanalization of a tandem lesion and the putative higher risk should not result in reluctant treatment that would decrease the chance of a good clinical outcome.

Perception and use of reversible contraceptive methods in Germany: A social listening analysis

BACKGROUND

With an increasing array of contraceptives in the market, it is important to understand how users perceive them and how their interests evolve over time.

OBJECTIVES

In this analysis, we aimed to examine the contraceptive interests of women and couples in Germany using data derived from social media posts.

STUDY DESIGN

Social listening analysis.

METHODS

Posts from Urbia-a German Internet community-mentioning at least one reversible contraceptive method between April 2006 and April 2021 were carefully selected by searching for a defined set of keywords and phrases. The frequency of mention of each method was studied and their trend over the last 5 years was analyzed. The significance of trends was evaluated using Mann-Kendall test. Additionally, 656 random posts were individually assessed for method transitions and problems associated with specific contraceptives.

RESULTS

The contraceptive pill was the most frequently mentioned method of contraception followed by natural family planning methods, condom, hormonal coil, and copper/gold coil. Although general interest in hormonal contraception was higher compared to non-hormonal, interest in the pill decreased and interest in natural family planning and copper/gold coil increased. Most women switched from the pill to non-hormonal methods, almost half of them using a condom. Almost all migrations to natural family planning were from the pill and most migrations to non-hormonal intrauterine devices such as the coil were from hormonal methods. The common problem associated with most contraceptives was side effects.

CONCLUSION

Social media provides valuable information about contraceptive experiences that can be used to monitor contraceptive prevalence patterns and attitudes within a large population in a very short span of time. A good understanding of how various contraceptives are currently perceived helps in identifying strategies for improving existing family planning policies.

PLAIN LANGUAGE SUMMARY

Currently, there are a variety of contraceptive products available in the market. To understand how users perceive them and how their interest evolves over time, we analyzed social media posts from Urbia, a German Internet platform. We scraped posts between 2016 and 2021 from the "child-desire" and "contraception" forums and analyzed the relative frequency of mentions of different contraceptive methods. We also looked at 1000 individual posts from 1000 different users, analyzed method switches and the problems associated with individual methods of use. The oral pill was the most frequently mentioned method of contraception followed by natural family planning methods, condom, hormonal coil, and copper/gold coil. Over the last 5 years however, the mention of the pill dropped, whereas the mentions of natural family planning and copper or gold coil increased. Further analysis of individual posts showed most women migrating from the pill to other non-hormonal methods such as natural family planning and condom. Almost all migrations to natural family planning were from the pill and most migrations to non-hormonal intrauterine devices such as the coil were from hormonal methods. The most common problem associated with the pill and non-hormonal intrauterine devices was side effects. Through this analysis we show that social media serves as a useful tool to monitor contraceptive prevalence and attitudes within a large population in a very short span of time. Our findings give policy makers an idea on the topics where more counseling and education may be required to help women and couples find their best suited method of contraception.

Correlation and differences of patient-reported outcomes vs. Likert-Rating of MS symptoms in a real-world cohort using a digital patient app

Background

Multiple Sclerosis (MS) is a chronic and progressive neurological autoimmune disease currently affecting 250,000 individuals in Germany. Patients suffering from the disease can be severely impaired in their day-to-day activities. BRISA is a digital app specifically designed to help MS patients monitor their disease by regularly tracking symptoms. Lengthy and time-consuming questionnaires for patient-reported outcomes (PRO) are the standard method to assess the patients' current condition. Here, we examine whether simplified versions of these questionnaires can provide comparable information regarding individual symptom presentations in BRISA users.

Methods

828 users were included in the analysis. Patients who provided onboarding information and answered at least one questionnaire and the corresponding simplified smiley symptoms assessment were included. Correlation of questionnaire and symptom scores was calculated using Pearson's correlation.

Results

Our analysis cohort predominantly consisted of female, 26-55-year-olds. Relapsing-remitting MS (RRMS) was the most common MS type recorded. Most patients were diagnosed 2-5 years ago. Questionnaires regarding fatigue and vision impairment were among the most answered, those regarding bowel movement and sexual satisfaction received fewest responses. Overall, the scores from questionnaires and symptoms correlated positively. Scoring correlation could also be shown across the subgroups divided by gender, age groups, type of MS, and time since diagnosis of the disease.

Conclusion

Scores recorded from traditional PRO questionnaires can be reflected more easily as a trend in a simplified scale using smileys. Nevertheless, traditional questionnaires are needed to also maintain a more objective assessment. In conclusion, the patient will benefit most from an adaptive combination of regular traditional PRO questionnaire assessments and simplified symptom recording.

Demographic Patterns of MS Patients Using BRISA: An MS-Specific App in Germany

Background: Multiple sclerosis (MS) is a chronic, progressive neurological autoimmune disease impacting quality of life. BRISA is an app designed to help MS patients in Germany track their disease course by symptom-monitoring. This study aimed to understand demographic and health-related characteristics of BRISA users. Methods: Demographic data provided by 2095 users were analyzed to describe characteristics such as sex, age, type of MS, and medication. The distribution of tracked symptoms based on age and time since diagnosis were studied. Furthermore, the covariance of specific symptom pairs was analyzed. Results: BRISA users are predominantly female and between 26 and 55 years old. Relapsing–remitting MS was the most prevalent form of MS. First-line category 1 drugs were most frequently used, followed by high-efficacy category 3 drugs (e.g., monoclonal antibodies). The relative frequencies of use of category 1 and category 2 drugs (e.g., spingosine-1-phosphate-receptor modulators) significantly altered with time since diagnosis. Fatigue, concentration disorders, tingling, forgetfulness, and pain were the top five symptoms affecting users. Conclusion: The results highlight the diversity among MS patients and the need for extensive cohort characterization in the real-world scenario. In-depth analysis could help in identifying novel insights that could aid in disease management.

Structured reporting of brain MRI following mechanical thrombectomy in acute ischemic stroke patients

Background

To compare the quality of free-text reports (FTR) and structured reports (SR) of brain magnetic resonance imaging (MRI) examinations in patients following mechanical thrombectomy for acute stroke treatment.

Methods

A template for SR of brain MRI examinations based on decision trees was designed and developed in house and applied to twenty patients with acute ischemic stroke in addition to FTR. Two experienced stroke neurologists independently evaluated the quality of FTR and SR regarding clarity, content, presence of key features, information extraction, and overall report quality. The statistical analysis for the differences between FTR and SR was performed using the Mann–Whitney U-test or the Chi-squared test.

Results

Clarity (p < 0.001), comprehensibility (p < 0.001), inclusion of relevant findings (p = 0.016), structure (p = 0.005), and satisfaction with the content of the report for immediate patient management (p < 0.001) were evaluated significantly superior for the SR by both neurologist raters. One rater additionally found the explanation of the patient’s clinical symptoms (p = 0.003), completeness (p < 0.009) and length (p < 0.001) of SR to be significantly superior compared to FTR and stated that there remained no open questions, requiring further consultation of the radiologist (p < 0.001). Both neurologists preferred SR over FTR.

Conclusions

The use of SR for brain magnetic resonance imaging may increase the report quality and satisfaction of the referring physicians in acute ischemic stroke patients following mechanical thrombectomy.

Trial registration Retrospectively registered.

The "Flying Intervention Team": A Novel Stroke Care Concept for Rural Areas

BACKGROUND

Endovascular treatment of large vessel occlusion in acute ischemic stroke patients is difficult to establish in remote areas, and time dependency of treatment effect increases the urge to develop health care concepts for this population.

SUMMARY

Current strategies include direct transportation of patients to a comprehensive stroke center (CSC) ("mothership model") or transportation to the nearest primary stroke center (PSC) and secondary transfer to the CSC ("drip-and-ship model"). Both have disadvantages. We propose the model "flying intervention team." Patients will be transported to the nearest PSC; if telemedically identified as eligible for thrombectomy, an intervention team will be acutely transported via helicopter to the PSC and endovascular treatment will be performed on site. Patients stay at the PSC for further stroke unit care. This model was implemented at a telestroke network in Germany. Fifteen remote hospitals participated in the project, covering 14,000 km2 and a population of 2 million. All have well established telemedically supported stroke units, an angiography suite, and a helicopter pad. Processes were defined individually for each hospital and training sessions were implemented for all stroke teams. An exclusive project helicopter was installed to be available from 8 a.m. to 10 p.m. during 26 weeks per year. Key Messages: The model of the flying intervention team is likely to reduce time delays since processes will be performed in parallel, rather than consecutively, and since it is quicker to move a medical team rather than a patient. This project is currently under evaluation (clinicaltrials NCT04270513).

The burden of incontinence in a real-world data environment-insights from a digital patient companion

Introduction and hypothesis

Urinary incontinence (UI) has a potentially devastating effect on women’s quality of life (QoL). Conservative treatment by means of pelvic floor muscle training is the first-choice treatment modality. Nowadays, this can be supported by digital apps like pelvina©—a digital health companion pelvic floor course.

Methods

Using pelvina©, UI symptoms and QoL are regularly examined through the questionnaires QUID and SF-6D. Subsequently, we analyzed the incidence and degree of UI and its impact on QoL in 293 users in a real-world environment.

Results

The 293 patients included in this study had a median age of 36 years and a median of two children. Patients were slightly to moderately affected by UI with a QUID of 6 (2–11, maximum 24). Age and number of children were independently associated with the incidence of UI with an adjusted odds ratio (aOR) of 1.06 (95% CI 1.01–1.12) and aOR of 1.86 (95% CI 1.12–3.08). The severity of UI strongly correlated with impairment of QoL (ρ = 0.866, P < 0.001).

Conclusions

The use of real-world data generated by digital health solutions offers the opportunity to gain insight into the reality of patients’ lives. In this article, we corroborate the known associations between number of children and UI as well as the great influence UI has on QoL. This study shows that, in the future, the use of digital apps can make an important contribution to scientific data acquisition and, for example, therapy monitoring.

Improved Reliability of Automated ASPECTS Evaluation Using Iterative Model Reconstruction from Head CT Scans

BACKGROUND AND PURPOSE

Iterative model reconstruction (IMR) has shown to improve computed tomography (CT) image quality compared to hybrid iterative reconstruction (HIR). Alberta Stroke Program Early CT Score (ASPECTS) assessment in early stroke is particularly dependent on high-image quality. Purpose of this study was to investigate the reliability of ASPECTS assessed by humans and software based on HIR and IMR, respectively.

METHODS

Forty-seven consecutive patients with acute anterior circulation large vessel occlusions (LVOs) and successful endovascular thrombectomy were included. ASPECTS was assessed by three neuroradiologists (one attending, two residents) and by automated software in noncontrast axial CT with HIR (iDose4; 5 mm) and IMR (5 and 0.9 mm). Two expert neuroradiologists determined consensus ASPECTS reading using all available image data including MRI. Agreement between four raters (three humans, one software) and consensus were compared using square-weighted kappa (κ).

RESULTS

Human raters achieved moderate to almost perfect agreement (κ = .557-.845) with consensus reading. The attending showed almost perfect agreement for 5 mm HIR (κ_HIR  = .845), while residents had mostly substantial agreements without clear trends across reconstructions. Software had substantial to almost perfect agreement with consensus, increasing with IMR 5 and 0.9 mm slice thickness (κ_HIR  = .751, κ_IMR  = .777, and κ_IMR0.9  = .814). Agreements inversely declined for these reconstructions for the attending (κ_HIR  = .845, κ_IMR  = .763, and κ_IMR0.9  = .681).

CONCLUSIONS

Human and software rating showed good reliability of ASPECTS across different CT reconstructions. Human raters performed best with the reconstruction algorithms they had most experience with (HIR for the attending). Automated software benefits from higher resolution with better contrasts in IMR with 0.9 mm slice thickness.

Basal Ganglia versus Peripheral Infarcts: Predictive Value of Early Fiber Alterations

BACKGROUND AND PURPOSE

Impairment of fiber integrity of the corticospinal tract in the subacute and chronic phases after ischemic stroke has been linked to poor motor outcome. The aim of the study was an assessment of fiber integrity in the acute poststroke phase and an evaluation of its association with the clinical course dependent on the infarction pattern (subtypes: peripheral versus basal ganglia infarction).

MATERIALS AND METHODS

All patients who underwent mechanical recanalization of a large-vessel occlusion in the anterior circulation and postinterventional DTI were included (n = 165). The fractional anisotropy index of the patient-specific corticospinal tract within the posterior limb of the internal capsule was correlated to clinical parameters (NIHSS scores/mRS at 90 days), and the interaction of stroke subtype (peripheral infarcts versus basal ganglia infarction) was tested in a moderation analysis.

RESULTS

The fractional anisotropy index was reduced in the acute poststroke phase with a correlation to clinical presentation, especially in case of peripheral infarcts (eg, with the NIHSS motor subscore: r = -0.4, P < .001). This correlation was absent for basal ganglia infarction (r = -0.008, P > .05). There was a significant association between the fractional anisotropy index and clinical outcome (mRS after 90 days, P < .01), which is moderated by stroke subtype with significant effects only for peripheral infarcts.

CONCLUSIONS

Corticospinal tract abnormalities can be observed in the early stage after mechanical recanalization and have prognostic capacity. This finding increases the clinical value of early DTI imaging parameters. Because the effects observed were limited to peripheral infarcts, further and longitudinal evaluation of fiber integrities within basal ganglia infarction is required.

A short history of thrombectomy - Procedure and success analysis of different endovascular stroke treatment techniques

Background

The historical development of interventional stroke treatment shows a wide variation of different techniques and materials used. Thus, the question of the present work is whether the technical and procedural differences of thrombectomy techniques lead to different technical and clinical results.

Methods and results

Analysis of a mixed retrospective/prospective database of all endovascular treated patients with an occlusion of the Carotid-T or M1 segment of the MCA at a single comprehensive stroke center since 2008. Patients were classified regarding the technical approach used. Six hundred sixty-eight patients were available for the final analysis. Reperfusion rates ranged between 56% and 100% depending on the technical approach. The use of balloon guide catheters and most recently the establishment of combination techniques using balloon guide catheters, aspiration catheters and stent retrievers have shown a further significant increase in the rates of successful recanalization, full recanalization and first-pass recanalization. Additionally, the technical development of interventional techniques has led to a subsequent drop in complications, embolization into previously unaffected territories in particular.

Conclusion

Technical success of MT has improved substantially over the past decade owing to improved materials and procedural innovations. Combination techniques including flow modulation have emerged to be the most effective approach and should be considered as a standard of care.

Level of evidence: Level 3, retrospective study.

Thrombus Histology of Basilar Artery Occlusions : Are There Differences to the Anterior Circulation?

BACKGROUND

For patients with acute vessel occlusions of the anterior circulation histopathology of retrieved cerebral thrombi has been reported to be associated to stroke etiology. Due to the relatively small incidence of posterior circulation stroke, exclusive histopathologic analyses are missing for this subgroup. The aim of the study was to investigate thrombus histology for patients with basilar artery occlusions and uncover differences to anterior circulation clots with respect to underlying etiology.

METHODS

A total of 59 basilar thrombi were collected during intracranial mechanical recanalization and quantitatively analyzed in terms of their relative fractions of the main constituents, e.g. fibrin/platelets (F/P), red (RBC) and white blood cells (WBC). Data were compared to histopathological analyses of 122 thrombi of the anterior circulation with respect to underlying pathogenesis.

RESULTS

The composition of basilar thrombi differed significantly to thrombi of the anterior circulation with an overall higher RBC amount (median fraction in % (interquartile range):0.48 (0.37-0.69) vs. 0.37 (0.28-0.50), p < 0.001) and lower F/P count (0.45 (0.21-0.58) vs. 0.57 (0.44-0.66), p < 0.001). Basilar thrombi composition did not differ between the different etiological stroke subgroups.

CONCLUSION

The results depict a differing thrombus composition of basilar thrombi in comparison to anterior circulation clots with an overall higher amount of RBC. This may reflect different pathophysiologic processes between anterior and posterior circulation thrombogenesis, e.g. a larger proportion of appositional thrombus growth in the posterior circulation.

Introduction of CTA-index as Simplified Measuring Method for Thrombus Perviousness

PURPOSE

Thrombus features on admission CT are useful imaging markers for clot characterization, stroke pathogenesis and outcome prediction. In this context, thrombus perviousness is a promising parameter, but reliable assessment in daily clinical practice is demanding. The aim of the present study was to evaluate an easy to assess measuring method for thrombus permeability at the time of admission.

METHODS

The CTA-index, which measures relative thrombus attenuation on admission CTA, was compared to the known perviousness parameter in a cohort of 101 patients with large-vessel occlusions of the middle cerebral artery and correlated to clinical outcome parameters (mRS after 90 days, ≤2 rated as favorable). For validation, this correlation was tested in a second independent cohort (n = 87), and possible associations between the CTA-index and outcome measurements (NIHSS/mRS/mTICI) were assessed.

RESULTS

In the first cohort a coherence between conventional perviousness measurements and the CTA-index was shown. The CTA-index differed significantly between favorable (-0.55 ± 0.16) and non-favorable outcomes (-0.64 ± 0.14, p = 0.01). In the validation cohort this result could be independently reproduced (-0.52 ± 0.13/-0.70 ± 0.09, p < 0.01). The CTA-index showed an association with low NIHSS at discharge (p < 0.01), favorable outcome after 90 days (p < 0.001) and with better reperfusion (measured by mTICI score, p = 0.04).

CONCLUSION

The CTA-index is an easy to assess imaging parameter on admission CTA in the acute stroke phase and is associated with angiographic and clinical outcome. It can be considered as a simplified measuring method for thrombus perviousness, which is known to provide useful information for further stroke progress and clinical course as well as therapeutic and rehabilitative decisions.

Thrombus NET content is associated with clinical outcome in stroke and myocardial infarction

OBJECTIVE

To investigate whether immune cell composition and content of neutrophil extracellular traps (NETs) in relation to clinical outcome are different between acute ischemic stroke (AIS) and acute myocardial infarction (AMI), we performed histologic analysis and correlated results with clinical and procedural parameters.

METHODS

We retrieved thrombi from patients with AIS (n = 71) and AMI (n = 72) during endovascular arterial recanalization and analyzed their immune cell composition and NET content by immunohistology. We then associated thrombus composition with procedural parameters and outcome in AIS and with cardiac function in patients with AMI. Furthermore, we compared AIS thrombi with AMI thrombi and differentiated Trial of Org 10172 in Acute Stroke Treatment classifications to address potential differences in thrombus pathogenesis.

RESULTS

Amounts of leukocytes (p = 0.133) and neutrophils (p = 0.56) were similar between AIS and AMI thrombi. Monocytes (p = 0.0052), eosinophils (p < 0.0001), B cells (p < 0.0001), and T cells (p < 0.0001) were more abundant in stroke compared with AMI thrombi. NETs were present in 100% of patients with AIS and 20.8% of patients with AMI. Their abundance in thrombi was associated with poor outcome scores in patients with AIS and with reduced ejection fraction in patients with AMI.

CONCLUSION

In our detailed histologic analysis of arterial thrombi, thrombus composition and especially abundance of leukocyte subsets differed between patients with AIS and AMI. The presence and amount of NETs were associated with patients' outcome after AIS and AMI, supporting a critical impact of NETs on thrombus stability in both conditions.

Impact of brain volume and intracranial cerebrospinal fluid volume on the clinical outcome in endovascularly treated stroke patients

PURPOSE

Previously, brain volume (BV) and intracranial cerebrospinal fluid volume (CSFV) have been investigated regarding clinical outcomes of subgroups of ischemic stroke patients. This study aimed to examine if the preexisting, preischemic BV and CSFV have an impact on good functional outcome and mortality in acute ischemic stroke (AIS) patients treated with mechanical thrombectomy (MT).

METHODS

Preischemic BV, CSFV, and CSFV/Total intracranial volume (TICV)-ratio were calculated with a fully automated segmentation platform. Univariate and multivariate analyses were used to study associations.

RESULTS

In this retrospective study 107 subsequent AIS patients of a prospective database were included. The segmentation results of the fully automated algorithm based on non-contrast computerized tomography scans (NCCT) correlated significantly with the segmentation results obtained from 3D T1 weighted magnetic resonance images (P < 0.001). In the univariate analysis a preexisting BV (P < 0.001), preexisting CSFV (P = 0.009), and the ratio CSFV/total intracranial volume (P < 0.001) each significantly correlated with good functional outcome and mortality. However, in the multivariate regression analysis, also correcting for patient age, none of these volumes remained to correlate with these outcome parameters.

CONCLUSION

In summary, an association of BV, CSFV, and the CSFV/TICV-ratio with good functional outcome and mortality in AIS treated with MT could not be established. A fully automated segmentation algorithm based on NCCT was successfully developed in-house for calculating the volumes of interest.

Intrathecal nusinersen administration in adult spinal muscular atrophy patients with complex spinal anatomy

Background:

Intrathecal administration of nusinersen in adult spinal muscular atrophy (SMA) patients presents challenges owing to severe scoliosis and previous spinal surgery with metal implantation. In patients with a complex spinal situation, the potential risks of the intrathecal administration may lead to delayed treatment initiation.

Methods:

In this study, we analyzed 53 CT-guided lumbar punctures of 11 adult nonambulatory SMA type 2 and 3 patients. All patients had scoliosis and six patients had previously undergone metal implantation.

Results:

Drug administration was successful in 100% of the patients and none of the patients opted for treatment discontinuation. Complete osseous fusion precluded conventional posterior interlaminar access in eight lumbar punctures in four patients, which required alternative routes including transforaminal punctures and translaminar drilling. Median duration of all lumbar punctures was 9 min and median radiation exposure was 100 mGy* cm. The most common adverse event was post-lumbar puncture syndrome that occurred in five lumbar punctures (9.4%).

Conclusions:

Our data demonstrate that nusinersen can be successfully, safely, and rapidly administered in adult SMA patients with complex spinal conditions and suggest the translaminar drilling technique as an alternative delivery route. Therefore, intrathecal nusinersen treatment should not be withheld from patients because of severe spine deformities, however, drug efficacy in adult SMA patients needs to be investigated in further studies.

Mechanical Thrombectomy in Ischemic Stroke Patients With Alberta Stroke Program Early Computed Tomography Score 0-5

Supplemental Digital Content is available in the text.

Background and Purpose—

If anterior circulation large vessel occlusion acute ischemic stroke patients presenting with ASPECTS 0–5 (Alberta Stroke Program Early CT Score) should be treated with mechanical thrombectomy remains unclear. Purpose of this study was to report on the outcome of patients with ASPECTS 0–5 treated with mechanical thrombectomy and to provide data regarding the effect of successful reperfusion on clinical outcomes and safety measures in these patients.

Methods—

Multicenter, pooled analysis of 7 institutional prospective registries: Bernese-European Registry for Ischemic Stroke Patients Treated Outside Current Guidelines With Neurothrombectomy Devices Using the SOLITAIRE FR With the Intention for Thrombectomy (Clinical Trial Registration—URL: https://www.clinicaltrials.gov. Unique identifier: NCT03496064). Primary outcome was defined as modified Rankin Scale 0–3 at day 90 (favorable outcome). Secondary outcomes included rates of day 90 modified Rankin Scale 0–2 (functional independence), day 90 mortality and occurrence of symptomatic intracerebral hemorrhage. Multivariable logistic regression analyses were performed to assess the association of successful reperfusion with clinical outcomes. Outputs are displayed as adjusted Odds Ratios (aOR) and 95% CI.

Results—

Two hundred thirty-seven of 2046 patients included in this registry presented with anterior circulation large vessel occlusion and ASPECTS 0–5. In this subgroup, the overall rates of favorable outcome and mortality at day 90 were 40.1% and 40.9%. Achieving successful reperfusion was independently associated with favorable outcome (aOR, 5.534; 95% CI, 2.363–12.961), functional independence (aOR, 5.583; 95% CI, 1.964–15.873), reduced mortality (aOR, 0.180; 95% CI, 0.083–0.390), and lower rates of symptomatic intracerebral hemorrhage (aOR, 0.235; 95% CI, 0.062–0.887). The mortality-reducing effect remained in patients with ASPECTS 0–4 (aOR, 0.167; 95% CI, 0.056–0.499). Sensitivity analyses did not change the primary results.

Conclusions—

In patients presenting with ASPECTS 0–5, who were treated with mechanical thrombectomy, successful reperfusion was beneficial without increasing the risk of symptomatic intracerebral hemorrhage. Although the results do not allow for general treatment recommendations, formal testing of mechanical thrombectomy versus best medical treatment in these patients in a randomized controlled trial is warranted.

Microstructural Integrity of Salvaged Penumbra after Mechanical Thrombectomy

BACKGROUND AND PURPOSE

There are sparse data on the microstructural integrity of salvaged penumbral tissue after mechanical thrombectomy of large-vessel occlusions. The aim of the study was to analyze possible microstructural alteration in the penumbra and their association with clinical symptoms as well as angiographic reperfusion success in patients undergoing mechanical thrombectomy.

MATERIALS AND METHODS

All patients who underwent mechanical thrombectomy for large-vessel occlusions in the anterior circulation and who received an admission CT perfusion together with postinterventional DTIs were included (n = 65). Angiographic reperfusion success by means of modified Thrombolysis in Cerebral Infarction (mTICI) scale and clinical outcome were recorded. Microstructural integrity was assessed by DTI evaluating the mean diffusivity index within the salvaged gray matter of the former penumbra.

RESULTS

The mean diffusivity index was higher in completely recanalized patients (mTICI 3: -0.001 ± 0.034 versus mTICI <3: -0.030 ± 0.055, P = .03). There was a positive correlation between the mean diffusivity index and NIHSS score improvement (r = 0.49, P = .003) and the mean diffusivity index was associated with midterm functional outcome (r = -0.37, P = .04) after adjustment for confounders. In mediation analysis, the mean diffusivity index and infarction growth mediated the association between reperfusion success and clinical outcomes.

CONCLUSIONS

The macroscopic salvaged penumbra included areas of microstructural integrity changes, most likely related to the initial hypoperfusion. These abnormalities were found early after mechanical thrombectomy, were dependent on angiographic results, and correlated with the clinical outcome. When confirmed, these findings prompt the evaluation of therapies for protection of the penumbral tissue integrity.

Mechanical Thrombectomy of the Middle Cerebral Artery - Neither Segment nor Diameter Matter

OBJECTIVES

The aim of this study was to explore the role of the vessel diameter at the site of middle cerebral artery (MCA) occlusion in acute ischemic stroke patients who underwent mechanical thrombectomy (MT) regarding technical aspects, safety, and clinical outcomes.

METHODS

In a retrospective analysis, cerebral artery diameters were measured using digital subtraction angiography in patients with isolated M1 or M2 occlusions undergoing MT. Associations between occluded vessel, occlusion diameter and outcomes were analyzed using logistic regression models adjusting for prespecified prognostic factors.

RESULTS

168 patients with M1 occlusions and 98 patients with M2 occlusions who underwent MT were included. Mean vessel diameters at M1 and M2 occlusion sites differed significantly (2.15 +/- .36 1.55 +/- .38, P < .001). Vessel diameters at the occlusion site and occluded vessel segment did not predict good functional outcome (aOR 1.2 CI .28-5.26, P = .659; aOR .84 CI .35-2.03, P = .841) or mortality (aOR .21 CI .04-1.01, P = .215; aOR 1.36 CI .55-3.37, P = .676). No significant differences in successful recanalization, good functional outcome, mortality, procedural complications, and intracranial hemorrhages between M1 and M2 occlusions was observed.

CONCLUSIONS

In this study no significant effect of the MCA vessel diameter on successful recanalization, good functional outcome, or mortality of acute ischemic stroke patients treated with MT could be detected. However, these findings need to be confirmed in further studies.

Etiology of recurrent large vessel occlusions treated with repeated thrombectomy

BACKGROUND

Repeated mechanical thrombectomy for acute stroke treatment in individual patients has been proven feasible. However, less is known about the etiology of recurrent vessel occlusions after prior thrombectomy. We aimed to understand if the etiology of such recurrent events differs from the first stroke.

METHODS

Retrospectively, we identified all patients at our center who received a repeated mechanical thrombectomy between 2007 and 2019. Clinical data were retrieved from medical records. Etiology of stroke was evaluated retrospectively, and angiographic studies were revisited.

RESULTS

Twenty-three patients (1.5%) were identified. Median age was 68 years (IQR 56-77). Median NIHSS at first admission was 11 points (IQR 5-15). In nine cases (39.1%), the recurrent vessel occlusion was located exactly at the same position as the prior occlusion. Overall, five (21.7%) patients had a remarkable extracranial pathology as likely cause of stroke recurrence. In 16 patients (69.6%), the etiology of the first stroke and its recurrence was considered as likely being the same, mostly of cardioembolic or unknown origin. In the seven remaining patients (30.4%), the cause of stroke possibly differed from the first event, with five patients (21.7%) having a postinterventional intracranial intimal lesion as possible cause of stroke.

CONCLUSION

Incidence of repeated thrombectomy was low. However, the high number of patients with known origin of stroke etiology raises the question how their monitoring may be optimized. The number of patients with remarkable extracranial pathologies or intracranial endothelial lesions supports current clinical practice to pay attention to final angiographic series.

Angiographic Baseline Proximal Thrombus Appearance of M1/M2 Occlusions in Mechanical Thrombectomy

PURPOSE

Analyzing stroke thrombi has proven to be valuable in prognostication and risk stratification of stroke etiology, reperfusion success and outcomes. The aim of this study was to test if the baseline appearance of the proximal thrombus on digital subtraction angiography (DSA) can predict these parameters in acute ischemic stroke patients treated with mechanical thrombectomy.

METHODS

The appearance of the most proximal part of the thrombus was determined based on DSA. Thrombus perviousness, density, and histology were measured beforehand as described previously. Baseline, technical, and outcome variables were compared using the χ²-test, analysis of variance and the Kruskal-Wallis test.

RESULTS

A total of 144 stroke patients with M1 and M2 occlusions could be included in this present study. Of the patients 60.4% had a cutoff, 27.1% a tapered, and 12.5% a meniscus/tram-track appearance of the thrombus on baseline DSA. The number of maneuvers was higher in the cutoff cohort (P = 0.003). Age (P = 0.777), female sex (P = 0.936), administration of intravenous thrombolysis (P = 0.364), percentage of M1 occlusions (P = 0.194), Alberta Stroke Program early computed tomography score (ASPECTS, P = 0.256), usage of balloon guide catheters (P = 0.367), general anesthesia (P = 0.184), procedure time (P = 0.214) and symptom onset to groin puncture time (P = 0.114) did not significantly differ. Alongside a lower National Institutes of Health scale (NIHSS) score on admission (P = 0.085), good functional outcome was favorable for the meniscus/tram-track cohort (P = 0.030). Stroke etiology according to the trial of Org 10172 in acute stroke treatment (TOAST) criteria as well as thrombus perviousness, density, and histology showed no association with the thrombus appearance.

CONCLUSION

Baseline cut off thrombus appearance predicts a higher number of thrombectomy maneuvers. In day to day practice this may prepare the neurointerventionalist for a more challenging endovascular procedure ahead. Stroke etiology, clinical outcomes and thrombus-specific characteristics did not show any associations with the thrombus appearance.

Heterogeneous Clusters of Phthalocyanine and Water Prepared and Probed in Superfluid Helium Nanodroplets

Superfluid helium nanodroplets comprised of thousands to millions of helium atoms can serve as a reactor for the synthesis of heterogeneous molecular clusters at cryogenic conditions. The cluster synthesis occurs via consecutive pick-up of the cluster building blocks by the helium droplet and their subsequent coalescence within the droplet. The effective collision cross section of the building blocks is determined by the helium droplet size and thus exceeds by orders of magnitude that of a reactive collision in the gas phase. Moreover, the cryogenic helium environment (at 0.38 K) as a host promotes the formation of metastable cluster configurations. The question arises as to the extent of the actual involvement of the helium environment in the cluster formation. The present study deals with clusters of single phthalocyanine (Pc) molecules with single water molecules. A large fluorophore such as Pc offers several sites where the water molecule can attach. The resulting isomeric variants of the Pc-H₂O complex can be selectively identified by electronic spectroscopy. We compare the experimental electronic spectra of the Pc-H₂O complex generated in superfluid helium nanodroplets with the results of quantum-chemical calculations on the same cluster but under gas-phase conditions. The number of isomeric variants observed in the helium droplet experiment comes out the same as that obtained from our gas-phase calculations.

Evaluation of flow changes after telescopic stenting of a giant fusiform aneurysm of the vertebrobasilar junction

BACKGROUND

The use of flow-diverters for non-saccular cerebral posterior circulation aneurysms requires complex deployment techniques and is associated with high mortality and morbidity. Therefore, further studies are required to clarify the effect of stenting on post-treatment hemodynamics in such aneurysms. In this study, we evaluated flow alterations in a treated giant fusiform aneurysm of the vertebrobasilar junction and correlated them with the clinical outcome.

METHODS

A patient-specific aneurysm model was acquired by rotational angiography, and three SILK flow-diverters (4.5 × 40, 5 × 40 and 5.5 × 40 mm) were virtually deployed in series along the basilar and right vertebral arteries. Image-based blood flow simulations before and after the treatment were performed under realistic pulsatile flow conditions. The flow reduction, velocity and wall shear stress (WSS) distribution, streamlines and WSS-derived parameters were evaluated before and after the treatment.

RESULTS

The computed velocity streamlines showed substantial alterations of the flow pattern in the aneurysm and successful redirection of blood flow along the series of flow-diverters with no flow through the overlapping stents. The obtained flow reduction of 86% was sufficient to create thrombogenic flow conditions. Moreover, a 6.2-fold increase in relative residence time and a decrease by 87% of time-averaged WSS contributed to a successful treatment outcome observed during the follow-up.

CONCLUSIONS

We found a correlation between the numerically predicted flow alterations and the available treatment outcome. This shows the potential of image-based simulations to be used in clinical practice for treatment planning and estimation of possible risk factors associated with a complex stent deployment in fusiform aneurysms of the posterior circulation.

Mechanical thrombectomy for basilar artery occlusion: efficacy, outcomes, and futile recanalization in comparison with the anterior circulation

BACKGROUND

Performing mechanical thrombectomy (MT) in patients with basilar artery occlusion (BAO) is currently not evidence-based.

OBJECTIVE

To compare patients' outcome, relative merits of achieving recanalization, and predictors of futile recanalization (FR) between BAO and anterior circulation large vessel occlusion (ACLVO) MT.

METHODS

In the multicenter BEYOND-SWIFT registry (NCT03496064), univariate and multivariate (displayed as adjusted Odds Ratios, aOR and 95% confidence intervals, 95%-CI) outcome comparisons between BAO (N=165) and ACLVO (N=1574) were performed. The primary outcome was favorable outcome at 90 days (modified Rankin Scale, mRS 0-2). Secondary outcome included mortality, symptomatic intracranial hemorrhage (sICH) and FR. The relative merits of achieving successful recanalization between ACLVO and BAO were evaluated with interaction terms.

RESULTS

MT in BAO was more often technically effective and equally safe in regards to mortality and sICH when compared to ACLVO. When adjusting for baseline differences, there was no significant difference between BAO vs ACLVO regarding rates of favorable outcome (aOR 0.986, 95%-CI 0.553 - 1.758). However, BAO were associated with increased rates of FR (aOR 2.146, 95%-CI 1.267 - 3.633). Predictors for FR were age, stroke severity, maneuver count and intracranial stenting. No significant heterogeneity on the relative merits of achieving successful recanalization on several outcome parameters were observed when comparing BAO and ACLVO.

CONCLUSIONS

In selected patients, similar outcomes can be achieved in BAO and ACLVO patients treated with MT. Randomized controlled trials comparing patient selection and interventional strategies seem warranted to avoid FR.

TRIAL REGISTRATION NUMBER

NCT03496064.

High-frequency wall vibrations in a cerebral patient-specific aneurysm model

The presence of high-frequency velocity fluctuations in aneurysms have been confirmed by in-vivo measurements and by several numerical simulation studies. Only a few studies have located and recorded wall vibrations in in-vitro experiments using physiological patient models. In this study, we investigated the wall fluctuations produced by a flowing perfusion fluid in a true-to-scale elastic model of a cerebral fusiform aneurysm using a laser Doppler vibrometer (LDV). The model was obtained from patient data. The experimental setup reproduced physiologically relevant conditions using a compliant perfusion system, physiological flow parameters, unsteady flow and a non-Newtonian fluid. Three geometrically identical models with different wall elasticities were used for measurements. The influence of five different flow rates was considered. Wall vibrations were predominantly found at frequencies in the range 40-60 Hz and 255-265 Hz. Their amplitude increased with increasing elasticity of the model, but the spectral peaks remained at about the same frequency. Varying the flow rate produced almost no changes in the frequency domain of the models. The frequency of the spectral peaks varied slightly between points at the lateral wall and at the bottom of the aneurysm. Indeed, embedding the model in a fluid during measurements produced higher and smoother amplitude fluctuations.

Outcome, efficacy and safety of endovascular thrombectomy in ischaemic stroke according to time to reperfusion: data from a multicentre registry

BACKGROUND AND PURPOSE

In acute ischaemic stroke (AIS) of the anterior circulation (AC) treated with mechanical thrombectomy (MT), data point to a decline of treatment effect with increasing time from symptom onset to treatment. However, the magnitude of the decline will depend on the clinical setting and imaging selection used. The aims of this study were (1) to evaluate the clinical effect of time to reperfusion (TTR); and (2) to assess the safety and technical efficacy of MT according to strata of TTR.

METHODS

Using the retrospective multicentre BEYOND-SWIFT registry data (ClinicalTrials.gov identifier: NCT03496064), we compared safety and efficacy of MT in 1461 patients between TTR strata of 0-180 min (n = 192), 180-360 min (n = 876) and >360 min (n = 393). Clinical effect of TTR was evaluated using multivariable logistic regression analyses adjusting for pre-specified confounders [adjusted odds ratios (aOR) and 95% confidence intervals (95% CI)]. Primary outcome was good functional outcome (modified Rankin Scale: mRS 0-2) at day 90.

RESULTS

Every hour delay in TTR was a significant factor related to mRS 0-2 (aOR 0.933, 95% CI 0.887-0.981) with an estimated 1.5% decreased probability of good functional outcome per hour delay of reperfusion, and mRS 0-1 (aOR 0.929, 95% CI 0.877-0.985). Patients with late TTR had lower rates of successful and excellent reperfusion, higher complication rates and number of passes.

CONCLUSIONS

TTR is an independent factor related to long-term functional outcome. With increasing TTR, interventional procedures become technically less effective. Efforts should be made to shorten TTR through optimized prehospital and in-hospital pathways.

Hippocampus subfield volumetry after microsurgical or endovascular treatment of intracranial aneurysms-an explorative study

BACKGROUND

To study hippocampus subfield volumes in patients after microsurgical clipping (MC) and/or endovascular coiling (EC) of intracranial aneurysms.

METHODS

Hippocampus subfield volumetry was performed using FreeSurfer v6.0 in 51 patients (35 females, mean age 54.9 ± 11.9 years, range 24-78 years). Visual inspection of image and segmentation quality was performed prior to statistical analyses. Multiple regression analysis, controlled for age, sex, and side of treatment, was used to assess the impact of prior MC and history of subarachnoid haemorrhage (SAH) on hippocampus subfield volumes (cornu ammonis (CA)-2/3, CA-4, subiculum). Partial correlation analyses were used to assess effect of multiple treatments on hippocampus subfield volumes.

RESULTS

Prior MC was significantly associated with lower hippocampal subfield volumes in MC patients for right and left CA-2/3 (β = -22.32 [-40.18, -4.45]; p = 0.016 and β = -20.03 [-39.38, -0.68]; p = 0.043) and right CA-4 (β = -17.00 [-33.86, 0.12]; p = 0.048). History of SAH was not significantly associated with hippocampal subfield volumes. We observed a higher disease burden in the MC cohort. The number of aneurysms correlated with right-sided hippocampal subfield volumes while the number of treatment interventions did not.

CONCLUSION

In this explorative study, we found that history of MC was significantly associated with lower volumes in distinct hippocampal subfields, which may be a consequence of a more extensive treatment. This could indicate specific atrophy of CA-2/3 after MC and should motivate hippocampal subfield assessment in larger cohorts.

Clinical effect of successful reperfusion in patients presenting with NIHSS < 8: data from the BEYOND-SWIFT registry

BACKGROUND AND PURPOSE

If patients presenting with large vessel occlusions (LVO) and mild symptoms should be treated with endvoascular treatment (EVT) remains unclear. Aims of this study were (1) assessing the safety and technical efficacy of EVT in patients with NIHSS < 8 as opposed to a comparison group of patients presenting with NIHSS ≥ 8 and (2) evaluation of the clinical effect of reperfusion in patients with NIHSS < 8.

METHODS

Patients included into the retrospective multicenter BEYOND-SWIFT registry (NCT03496064) were analyzed. Clinical effect of achieving successful reperfusion (defined as modified Thrombolysis in Cerebral Infarction grade 2b/3) in patients presenting with NIHSS < 8 (N = 193) was evaluated using multivariable logistic regression analyses (displayed as adjusted Odds Ratios, aOR and 95% confidence intervals, 95%-CI). Primary outcome was excellent functional outcome (modified Rankin Scale, mRS 0-1) at day 90. Safety and efficacy of mechanical thrombectomy in patients with NIHSS < 8 was compared to patients presenting with NIHSS ≥ 8 (N = 1423).

RESULTS

Among patients with NIHSS < 8 (N = 193, 77/193, 39.9% receiving pre-interventional IV-tPA), successful reperfusion was significantly related to mRS 0-1 (aOR 3.217, 95%-CI 1.174-8.816) and reduced the chances of non-hemorrhagic neurological worsening (aOR 0.194, 95%-CI 0.050-0.756) after adjusting for prespecified confounders. In interaction analyses, the relative merits of achieving successful reperfusion were mostly comparable between patients presenting with NIHSS < 8 and NIHSS ≥ 8 as evidenced by non-significantly different aOR. Interventional safety and efficacy metrics were similar between patients with NIHSS < 8 and NIHSS ≥ 8.

CONCLUSIONS

Achieving successful reperfusion is beneficial in patients with persisting LVO presenting with NIHSS < 8 and reduces the risk of non-hemorrhagic neurological worsening.

Vertebral Artery Patency and Thrombectomy in Basilar Artery Occlusions

Background and Purpose—

Factors influencing recanalization success in basilar artery occlusions are largely unknown. Preliminary evidence has suggested that flow arrest in the vertebral artery contralateral to the catheter bearing vertebral artery may facilitate recanalization. The aim of this analysis was to assess the impact of anatomic variations and flow conditions on recanalization success in basilar artery occlusion treated with mechanical thrombectomy.

Methods—

Consecutive basilar artery occlusions treated with second-generation thrombectomy devices at a single-center were retrospectively analyzed. Baseline patients’ characteristics, occlusion length, collateral circulation, underlying stenosis, incomplete occlusions, and patency of the vertebral arteries were analyzed with regards to recanalization success. Aplastic or hypoplastic vertebral artery contralateral to the catheter position was defined as contralateral low flow condition. Logistic regression analysis was used to examine the association between anatomic variations and flow conditions in relation to complete recanalization and the modified Rankin Scale score while controlling for several potentially confounding variables. Clinical impact was evaluated using the modified Rankin Scale score of ≤3.

Results—

One hundred fifteen patients were included (mean age 71.5±12.8, m:f=2:1, median National Institutes of Health Stroke Scale =15, interquartile range =10–22). Complete recanalization was more often observed in patients with contralateral low flow conditions (80.6% versus 50.0%), which remained an independent predictor of complete recanalization in multivariable analysis (adjusted odds ratio, 5.81; 95% CI, 1.97–17.19). Patients with complete posterior recanalization had lower in-hospital mortality (16.4% versus 41.7%) and more often achieved modified Rankin Scale score of ≤3 (49.4% versus 8.3%), even after adjusting for potential confounders (adjusted odds ratio, 15.93; 95% CI, 1.42–179.00).

Conclusions—

Contralateral low flow condition (vertebral artery aplasia or hypoplasia) seems to be an independent factor for fewer distal emboli and complete recanalization in basilar artery occlusion patients treated by modern endovascular devices. Complete recanalization reflecting the absence of peri-interventional clot fragmentation brings clear clinical benefit. Further studies are warranted to evaluate the need for contralateral flow modulation or ipsilateral balloon guide catheter during posterior circulation thrombectomy in patients with bilaterally patent vertebral arteries.

Neurosonography After Mechanical Thrombectomy for Acute Stroke Treatment

BACKGROUND AND PURPOSE

Mechanical thrombectomy has been shown to be effective for acute stroke treatment, but lesions of cerebral vessels can develop thereafter. Such lesions of recanalized vessels and altered cerebral hemodynamics after mechanical thrombectomy are poorly investigated. In particular for neurosonography, data are sparse. We aimed to describe hemodynamic changes and incidence of de-novo stenosis after mechanical thrombectomy with neurosonography.

METHODS

Retrospective analysis of patients after successful mechanical thrombectomy for acute stroke therapy who received one neurosonography at baseline and during follow up. Peak systolic velocity (PSV) of all intracranial recanalized and reference vessels was extracted for analysis. Patients with an isolated increase or decrease of PSV (50% or 50 cm/second for anterior and 30% or 30 cm/second for posterior circulation) were identified and characterized.

RESULTS

Eighty-eight patients (mean age 64.4; 34.1% female) were included in this study. In 9 (10.2%) patients, the vessel occlusion was located in the posterior, and in 79 (89.9%) patients the vessel occlusion was located in the anterior circulation. With predominance to the recanalized vessel, mean PSV decreased at both, the recanalized and the reference vessel during follow up. In 3 (3.4%) patients, an isolated increase of PSV was observed in the recanalized vessel, and in 6 (6.8%) patients an isolated decrease of PSV was observed in the recanalized vessel.

CONCLUSION

Sonographic incidence of de-novo stenosis following mechanical thrombectomy seems to be low, in line with prior angiographic studies. However, as measured by neurosonography, cerebral hemodynamic in the recanalized vessel is dynamic after thrombectomy. This result is of interest for further prospective analysis.

Microsolvation of porphine molecules in superfluid helium nanodroplets as revealed by optical line shape at the electronic origin

We investigate the line shape at the electronic origin of single porphine molecules doped into superfluid helium droplets as a function of the droplet size. Helium droplets comprised of less than 10⁵ atoms are generated from an expansion of gaseous helium, while droplets with more than 10⁵ atoms originate from liquid helium. In contrast to our recent study on phthalocyanine, porphine is found to exhibit a solvent shift to the blue with respect to the gas-phase resonance frequency as well as a multiplet splitting. A comparison of the helium-induced features of phthalocyanine and porphine with those obtained in similar studies on tetracene and pentacene reveals that these occur chiefly as two kinds of excitations distinguished by their linewidths and their dependence on the droplet size. Moreover, at quasi-bulk conditions achieved with droplets in excess of 10⁶ helium atoms, none of these four dopant species yields an optical spectrum that can be assigned to a plausible rotational band structure.

Further Development of Combined Techniques Using Stent Retrievers, Aspiration Catheters and BGC : The PROTECTPLUS Technique

PURPOSE

First pass complete (mTICI 3) reperfusion must be regarded as the ultimate goal in mechanical thrombectomy (MT) in patients suffering from an emergent large vessel occlusion (ELVO). With this in mind a technical modification of the previously published PROTECT (PRoximal balloon Occlusion TogEther with direCt Thrombus aspiration during stent retriever thrombectomy) approach, the PROTECT^PLUS technique was evaluated. Under proximal flow arrest using a balloon guide catheter (BGC), a stent retriever was only partially inserted into a large-bore aspiration catheter. This construction was subsequently retracted as a unit into the BGC with aspiration both at the aspiration catheter and at the BGC.

METHODS

A case-control study was performed comparing the PROTECT technique with the PROTECT^PLUS technique with respect to the technical and procedural parameters. Patients n = 165 (101 PROTECT, 64 PROTECT^PLUS) with ELVO of either the terminus of the internal carotid artery or the proximal middle cerebral artery were included.

RESULTS

Using the PROTECT^PLUS resulted in a higher rate of first pass complete reperfusions (59.4% vs. 27.7%, p < 0.001) as compared with PROTECT. The PROTECT^PLUS also led to shorter procedure times (21 min vs. 37 min, p = 0.001) and higher rates of overall complete reperfusion (73.5% vs. 49.5%, p = 0.014) compared to PROTECT.

CONCLUSION

The PROTECT^PLUS technique is a promising technical modification to further optimize endovascular stroke treatment.

Development of a hard X-ray split-and-delay line and performance simulations for two-color pump-probe experiments at the European XFEL

A hard X-ray Split-and-Delay Line (SDL) under construction for the Materials Imaging and Dynamics station at the European X-Ray Free-Electron Laser (XFEL) is presented. This device aims at providing pairs of X-ray pulses with a variable time delay ranging from -10 ps to 800 ps in a photon energy range from 5 to 10 keV for photon correlation and X-ray pump-probe experiments. A custom designed mechanical motion system including active feedback control ensures that the high demands for stability and accuracy can be met and the design goals achieved. Using special radiation configurations of the European XFEL's SASE-2 undulator (SASE: Self-Amplified Spontaneous Emission), two-color hard x-ray pump-probe schemes with varying photon energy separations have been proposed. Simulations indicate that more than 10⁹ photons on the sample per pulse-pair and up to about 10% photon energy separation can be achieved in the hard X-ray region using the SDL.

Microsolvation of phthalocyanine molecules in superfluid helium nanodroplets as revealed by the optical line shape at electronic origin

We investigate the solvent shift of phthalocyanine (Pc) doped into superfluid helium droplets and probed by optical spectroscopy at the electronic origin. Our present work complements extant studies and provides results that in part contradict previous conclusions. In particular, the solvent shift does not increase monotonously with droplet radius all the way up to the bulk limit, but exhibits just the reverse dependence instead. Moreover, a substructure is resolved, whose characteristics depend on the droplet size. This behavior can hardly be reconciled with that of a freely rotating Pc-helium complex.

Spinal ependymoma in adults: a multicenter investigation of surgical outcome and progression-free survival

OBJECTIVE Spinal ependymomas are rare glial neoplasms. Because their incidence is low, only a few larger studies have investigated this condition. There are no clear data concerning prognosis and therapy. The aim of the study was to describe the natural history, perioperative clinical course, and local tumor control of adult patients with spinal ependymomas who were surgically treated under modern treatment standards. METHODS The authors performed a multicenter retrospective study. They identified 158 adult patients with spinal ependymomas who had received surgical treatment between January 2006 and June 2013. The authors analyzed the clinical and histological aspects of these cases to identify the predictive factors for postoperative morbidity, tumor resectability, and recurrence. RESULTS Gross-total resection (GTR) was achieved in 80% of cases. At discharge, 37% of the patients showed a neurological decline. During follow-up the majority recovered, whereas 76% showed at least preoperative status. Permanent functional deterioration remained in 2% of the patients. Transient deficits were more frequent in patients with cervically located ependymomas (p = 0.004) and in older patients (p = 0.002). Permanent deficits were independently predicted only by older age (p = 0.026). Tumor progression was observed in 15 cases. The 5-year progression-free survival (PFS) rate was 80%, and GTR (p = 0.037), WHO grade II (p = 0.009), and low Ki-67 index (p = 0.005) were independent prognostic factors for PFS. Adjuvant radiation therapy was performed in 15 cases. No statistically relevant effects of radiation therapy were observed among patients with incompletely resected ependymomas (p = 0.079). CONCLUSIONS Due to its beneficial value for PFS, GTR is important in the treatment of spinal ependymoma. Gross-total resection is feasible in the majority of cases, with acceptable rates of permanent deficits. Also, Ki-67 appears to be an important prognostic factor and should be included in a grading scheme for spinal ependymomas.

Endovascular Stroke Treatment on Single-Plane vs. Bi-Plane Angiography Suites : Technical Considerations and Evaluation of Treatment Success

INTRODUCTION

Endovascular stroke therapy is mostly available in comprehensive stroke centers with state of the art bi-plane angiography suites. The aim of the present study was to analyze if it is justifiable to treat patients with alternative x‑ray machines in the case of capacity constraints, or if it is mandatory to refer patients in such cases. Secondly, we wanted to draw conclusions for the feasibility of different logistic approaches in stroke treatment, such as a "helistroke" concept.

METHODS

This was a retrospective dual center analysis of all patients treated on a single-plane angiography suite between 2009 and 2017. A propensity scored matching analysis at a 1:3 ratio was performed with patients treated on a bi-plane angiography suite to receive homogeneous groups.

RESULTS

A total of 42 patients were treated on a single-plane angiography suite and were compared to 126 patients treated on a bi-plane angiography suite. No significant differences in technical parameters, procedure times, recanalization success and complications could be detected. Also, there was no difference in the clinical outcome between the two groups. The only significant difference was the higher amount of radiation dose used on the bi-plane angiography machines to achieve the final results (205,660 mGy × cm² vs. 114,565 mGy × cm²; p < 0.001).

DISCUSSION

In an era of an ever-changing stroke infrastructure and an increasing demand in thrombectomy procedures, it is feasible and safe for experienced neurointerventionalists to perform endovascular stroke procedures on single-plane angiography units.

PROTECT: PRoximal balloon Occlusion TogEther with direCt Thrombus aspiration during stent retriever thrombectomy – evaluation of a double embolic protection approach in endovascular stroke treatment

Purpose

Stent retriever-based mechanical thrombectomy (MT) for emergent large vessel occlusions (ELVO) is often complicated by thrombus fragmentation causing distal embolization and embolization to new vascular territories. Well-established embolic protection approaches include proximal flow arrest and distal aspiration techniques during stent retriever maneuvers. Aiming at the reduction of thrombus fragmentation during MT we evaluated a technical approach combining proximal balloon occlusion together with direct thrombus aspiration during MT: the PROTECT technique.

Methods

We performed a case-control study comparing the PROTECT technique with sole distal aspiration during MT regarding technical and procedural parameters, n=200 patients with ELVO of either the terminus of the internal carotid artery or the proximal middle artery were included.

Results

PROTECT resulted in a shorter procedure time (29 vs 40 min; P=0.002), in a higher rate of successful recanalizations (100% vs 78%; P=0.001) and a higher rate of complete reperfusions (70% vs 39%; P<0.001) compared with sole distal aspiration during MT.

Conclusion

The PROTECT technique is a promising new approach to significantly reduce thrombus fragmentation and, hence distal embolization during MT. This safe and efficient technique needs to be validated in larger trials to confirm our results.

Endovascular Stroke Treatment: How Far Downstream Should We Go?

BACKGROUND

Endovascular thrombectomy has become the de facto standard in the treatment of large vessel occlusion. Previously, a correlation between good outcome and the occlusion site, measured by the 'distance to thrombus' (DT)-as the distance from the carotid T to the beginning of the thrombus-after thrombolysis could be shown. In the present study, we analyze the differences between the chances of a good outcome in respect of DT between patients treated endovascularly or intravenously.

METHODS

A dual-center database analysis including patients with stroke due to occlusion of the middle cerebral artery (MCA) was performed. Inclusion criteria were a completed treatment and full documentation of the clinical course. DT was measured in pre-treatment images. DT was correlated with the mRS at 90 days stratified according to the different treatment methods.

RESULTS

A total of 280 patients could be included. We were able to show a correlation between the chances of good clinical outcome and the occlusion site measured by DT after i.v. thrombolysis. The outcome after endovascular treatment showed no correlation with DT (p = 0.227). After a DT of 26 mm, the chances of a good outcome after i.v. thrombolysis exceeded those after endovascular treatment.

CONCLUSION

In patients with MCA occlusion, the probability for a good outcome after endovascular treatment is independent of the occlusion site in contrast to the treatment with i.v. thrombolysis. If the occlusion occurred in the periphery of the M2 region (DT > 26 mm), i.v. thrombolysis alone was superior to endovascular treatment in achieving a good outcome.

Impact of histological thrombus composition on preinterventional thrombus migration in patients with acute occlusions of the middle cerebral artery

Purpose The occurrence of thrombus migration (TM) in middle cerebral arteries (MCAs) prior to mechanical thrombectomy (MT) in patients suffering from acute ischemic strokes is a crucial aspect as TM is associated with lower rates of complete reperfusion and worse clinical outcomes. In this study, we sought to clarify whether histological thrombus composition influences TM. Methods We included 64 patients with acute MCA occlusions who had undergone MT. In 11 of the cases (17.2%) we identified TM prior to the interventions. The extracted clots were collected and histologically examined. The hematoxylin and eosin-stained specimens were quantitatively analyzed in terms of the relative fractions of the main constituents (red and white blood cells and fibrin/platelets). The histologic patterns were correlated with the occurrence of TM. Results Patients in whom TM could be observed were more often treated in a drip-and-ship fashion (90.9% vs 41.5%, p = 0.003). Stroke etiology did not differ between migrated and stable thrombi. A weak tendency for higher RBC and lower F/P content could be observed in thrombi that had migrated when compared with stable thrombi (RBC: median 41% vs 37%, p = 0.022 and F/P: median 54% vs 57%, p = 0.024). When using a cut-off of 60% RBC content for the definition of RBC-rich thrombi, a higher portion of RBC-rich thrombi could be identified in the migrated group as opposed to the stable group (36.4% vs 5.7%, p = 0.003). Conclusion Preinterventional TM may be influenced by the histological thrombus composition in a way that RBC-rich thrombi are more prone to migrate.