MRI hypoperfusion as a determinant of cognitive impairment in adults with Moyamoya angiopathy

INTRODUCTION

In Moyamoya angiopathy (MMA), mechanisms underlying cognitive impairment remain debated. We aimed to assess the association of cognitive impairment with the degree and the topography of cerebral hypoperfusion in MMA.

METHODS

A retrospective analysis of neuropsychological and perfusion MRI data from adults with MMA was performed. Ischemic and haemorrhagic lesion masks were created to account for cerebral lesions in the analysis of cerebral perfusion. Whole brain volume of hypoperfused parenchyma was outlined on perfusion maps using different Tmax thresholds from 4 to 12 s. Regional analysis produced mean Tmax values at different regions of interest. Analyses compared perfusion ratios in patients with and without cognitive impairment, with multivariable logistic regression analysis to identify predictive factors.

RESULTS

Cognitive impairment was found in 20/48 (41.7%) patients. Attention/processing speed and memory were equally impaired (24%) followed by executive domain (23%). After adjustment, especially for lesion volume, hypoperfused parenchyma volume outlined by Tmax > 4 s or Tmax > 5 s thresholds was an independent factor of cognitive impairment (OR for Tmax > 4 s = 1.06 [CI 95% 1.008-1.123]) as well as attention/processing speed (OR for Tmax > 4 s = 1.07 [CI 95% 1.003-1.133]) and executive domains (OR for Tmax > 5 s = 1.08 [CI 95% 1.004-1.158]). Regarding cognitive functions, patients with processing speed and flexibility impairment had higher frontal Tmax compared to other ROIs and to patients with normal test scores.

DISCUSSION

Cerebral hypoperfusion emerged as an independent factor of cognitive impairment in MMA particularly in attention/processing speed and executive domains, with a strong contribution of frontal areas.

CONCLUSION

Considering this association, revascularization surgery could improve cognitive impairment.

Silent brain infarct in migraine: Systematic review and meta-analysis

BACKGROUND

While migraine, particularly migraine with aura, is a recognized risk factor for ischemic stroke, the association of migraine with silent brain infarction is a matter of debate, as studies on this topic have yielded conflicting results.

METHODS

A systematic review of the literature was conducted of studies reporting migraine and silent brain infarction, assessed by magnetic resonance imaging, between January 1980 and April 2022, by consulting Medline and Embase databases. Studies with a control group were included in a meta-analysis of population-based studies. An exploratory meta-analysis of both population-based and clinical-based studies was further performed to test the association between migraine with aura and silent brain infarction.

RESULTS

A total of 2,408 articles were identified, among which 24 were included in the systematic review and 10 in the meta-analysis. The meta-analysis of population-based studies showed no association of migraine with silent brain infarction (odds ratio (OR)=1.32 [95% CI 0.92;1.90], P=0.13) and migraine with aura with silent brain infarction (OR=1.56 [0.74;3.30], P=0.24). However, in the exploratory meta-analysis of population-based and clinical-based studies, migraine with aura was significantly associated with silent brain infarction (OR=1.91 [1.02;3.59], P=0.04) and to silent cerebellar infarcts (OR=2.57 [1.01;6.56], P=0.05).

CONCLUSION

In this updated systematic review and meta-analysis of population-based studies, migraine and migraine with aura were not associated with silent brain infarction.

Safety and Efficacy of ApTOLL in Patients With Ischemic Stroke Undergoing Endovascular Treatment: A Phase 1/2 Randomized Clinical Trial

Importance

ApTOLL is a TLR4 antagonist with proven preclinical neuroprotective effect and a safe profile in healthy volunteers.

Objective

To assess the safety and efficacy of ApTOLL in combination with endovascular treatment (EVT) for patients with ischemic stroke.

Design, Setting, and Participants

This phase 1b/2a, double-blind, randomized, placebo-controlled study was conducted at 15 sites in Spain and France from 2020 to 2022. Participants included patients aged 18 to 90 years who had ischemic stroke due to large vessel occlusion and were seen within 6 hours after stroke onset; other criteria were an Alberta Stroke Program Early CT Score of 6 to 10, estimated infarct core volume on baseline computed tomography perfusion of 5 to 70 mL, and the intention to undergo EVT. During the study period, 4174 patients underwent EVT.

Interventions

In phase 1b, 0.025, 0.05, 0.1, or 0.2 mg/kg of ApTOLL or placebo; in phase 2a, 0.05 or 0.2 mg/kg of ApTOLL or placebo; and in both phases, treatment with EVT and intravenous thrombolysis if indicated.

Main Outcomes and Measures

The primary end point was the safety of ApTOLL based on death, symptomatic intracranial hemorrhage (sICH), malignant stroke, and recurrent stroke. Secondary efficacy end points included final infarct volume (via MRI at 72 hours), NIHSS score at 72 hours, and disability at 90 days (modified Rankin Scale [mRS] score).

Results

In phase Ib, 32 patients were allocated evenly to the 4 dose groups. After phase 1b was completed with no safety concerns, 2 doses were selected for phase 2a; these 119 patients were randomized to receive ApTOLL, 0.05 mg/kg (n = 36); ApTOLL, 0.2 mg/kg (n = 36), or placebo (n = 47) in a 1:1:√2 ratio. The pooled population of 139 patients had a mean (SD) age of 70 (12) years, 81 patients (58%) were male, and 58 (42%) were female. The primary end point occurred in 16 of 55 patients (29%) receiving placebo (10 deaths [18.2%], 4 sICH [7.3%], 4 malignant strokes [7.3%], and 2 recurrent strokes [3.6%]); in 15 of 42 patients (36%) receiving ApTOLL, 0.05 mg/kg (11 deaths [26.2%], 3 sICH [7.2%], 2 malignant strokes [4.8%], and 2 recurrent strokes [4.8%]); and in 6 of 42 patients (14%) receiving ApTOLL, 0.2 mg/kg (2 deaths [4.8%], 2 sICH [4.8%], and 3 recurrent strokes [7.1%]). ApTOLL, 0.2 mg/kg, was associated with lower NIHSS score at 72 hours (mean difference log-transformed vs placebo, -45%; 95% CI, -67% to -10%), smaller final infarct volume (mean difference log-transformed vs placebo, -42%; 95% CI, -66% to 1%), and lower degrees of disability at 90 days (common odds ratio for a better outcome vs placebo, 2.44; 95% CI, 1.76 to 5.00).

Conclusions and Relevance

In acute ischemic stroke, 0.2 mg/kg of ApTOLL administered within 6 hours of onset in combination with EVT was safe and associated with a potential meaningful clinical effect, reducing mortality and disability at 90 days compared with placebo. These preliminary findings await confirmation from larger pivotal trials.

Trial Registration

ClinicalTrials.gov Identifier: NCT04734548.

Abstract 69: Blood-brain Barrier Profile Influences Outcome After Mechanical Thrombectomy In The Frame Study

Background and Purpose: The FRAME study demonstrated that even in the early time window (<6hrs) perfusion imaging profiles can influence response to mechanical thrombectomy. Perfusion imaging (PWI) can also be used to measure damage to the blood-brain barrier (BBB) which has been shown to be associated with increased risk of hemorrhagic complications (HC) with treatment. We aimed to determine if BBB profiles in the FRAME study would influence outcome after mechanical thrombectomy (MT).

Methods: This was a post-hoc analysis of the FRAME study which enrolled stroke patients with large vessel occlusion who received MT within 6 hours of stroke onset. Patients with successful pre-treatment MRI PWI were included. We tested the hypothesis that more severe pre-treatment BBB disruption is associated with higher frequency of HC after MT. BBB disruption was measured as the percent of signal change due to gadolinium leakage on the PWI source images. Mean permeability derangement (MPD) was defined as the average of all voxels in the stroke core that are two standard deviations above normal. The outcome of HC was defined as any type of parenchymal hematoma (PH1 or PH2); poor functional outcome was defined as mRS >2 at 90 days. MPD was compared with HC and functional outcome using the Wilcoxon signed-rank test and logistic regression. A prespecified MPD threshold of 20% was tested as a predictor of HC based on prior studies.

Results: There were 164 patients included in the analysis, median age 74 and 48% female. HC occurred in 57 patients. The average MPD was 15.1% for patients with HC and 8.7% for patients without HC. Elevated MPD was significantly associated with HC (p<0.0001) with a 25% increased risk of HC for each 5% increase in MPD (OR 1.25; CI 1.09:1.45; p=0.0018). Increased MPD was also associated with poor functional outcome (p=0.0002). ROC analysis confirmed the prespecified MPD threshold, identifying 19.7% as the optimal cut point for classification. MPD greater than 20% more than tripled the risk of HC (OR 3.37; CI 1.49:7.85; p=0.004).

Conclusions: Increased pre-treatment BBB disruption has a substantial influence on the risk of HC after MT. Integration of BBB imaging into patient selection algorithms to improve MT outcomes should be tested further.

Endovascular treatment of brain arteriovenous malformations: clinical outcomes of patients included in the registry of a pragmatic randomized trial

OBJECTIVE

The role of endovascular treatment in the management of patients with brain arteriovenous malformations (AVMs) remains uncertain. AVM embolization can be offered as stand-alone curative therapy or prior to surgery or stereotactic radiosurgery (SRS) (pre-embolization). The Treatment of Brain AVMs Study (TOBAS) is an all-inclusive pragmatic study that comprises two randomized trials and multiple registries.

METHODS

Results from the TOBAS curative and pre-embolization registries are reported. The primary outcome for this report is death or dependency (modified Rankin Scale [mRS] score > 2) at last follow-up. Secondary outcomes include angiographic results, perioperative serious adverse events (SAEs), and permanent treatment-related complications leading to an mRS score > 2.

RESULTS

From June 2014 to May 2021, 1010 patients were recruited in TOBAS. Embolization was chosen as the primary curative treatment for 116 patients and pre-embolization prior to surgery or SRS for 92 patients. Clinical and angiographic outcomes were available in 106 (91%) of 116 and 77 (84%) of 92 patients, respectively. In the curative embolization registry, 70% of AVMs were ruptured, and 62% were low-grade AVMs (Spetzler-Martin grade I or II), while the pre-embolization registry had 70% ruptured AVMs and 58% low-grade AVMs. The primary outcome of death or disability (mRS score > 2) occurred in 15 (14%, 95% CI 8%–22%) of the 106 patients in the curative embolization registry (4 [12%, 95% CI 5%–28%] of 32 unruptured AVMs and 11 [15%, 95% CI 8%–25%] of 74 ruptured AVMs) and 9 (12%, 95% CI 6%–21%) of the 77 patients in the pre-embolization registry (4 [17%, 95% CI 7%–37%] of 23 unruptured AVMs and 5 [9%, 95% CI 4%–20%] of 54 ruptured AVMs) at 2 years. Embolization alone was confirmed to occlude the AVM in 32 (30%, 95% CI 21%–40%) of the 106 curative attempts and in 9 (12%, 95% CI 6%–21%) of 77 patients in the pre-embolization registry. SAEs occurred in 28 of the 106 attempted curative patients (26%, 95% CI 18%–35%, including 21 new symptomatic hemorrhages [20%, 95% CI 13%–29%]). Five of the new hemorrhages were in previously unruptured AVMs (n = 32; 16%, 95% CI 5%–33%). Of the 77 pre-embolization patients, 18 had SAEs (23%, 95% CI 15%–34%), including 12 new symptomatic hemorrhages [16%, 95% CI 9%–26%]). Three of the hemorrhages were in previously unruptured AVMs (3/23; 13%, 95% CI 3%–34%).

CONCLUSIONS

Embolization as a curative treatment for brain AVMs was often incomplete. Hemorrhagic complications were frequent, even when the specified intent was pre-embolization before surgery or SRS. Because the role of endovascular treatment remains uncertain, it should preferably, when possible, be offered in the context of a randomized trial.

The Boston criteria version 2.0 for cerebral amyloid angiopathy: a multicentre, retrospective, MRI-neuropathology diagnostic accuracy study

BACKGROUND

Cerebral amyloid angiopathy (CAA) is an age-related small vessel disease, characterised pathologically by progressive deposition of amyloid β in the cerebrovascular wall. The Boston criteria are used worldwide for the in-vivo diagnosis of CAA but have not been updated since 2010, before the emergence of additional MRI markers. We report an international collaborative study aiming to update and externally validate the Boston diagnostic criteria across the full spectrum of clinical CAA presentations.

METHODS

In this multicentre, hospital-based, retrospective, MRI and neuropathology diagnostic accuracy study, we did a retrospective analysis of clinical, radiological, and histopathological data available to sites participating in the International CAA Association to formulate updated Boston criteria and establish their diagnostic accuracy across different populations and clinical presentations. Ten North American and European academic medical centres identified patients aged 50 years and older with potential CAA-related clinical presentations (ie, spontaneous intracerebral haemorrhage, cognitive impairment, or transient focal neurological episodes), available brain MRI, and histopathological assessment for CAA diagnosis. MRI scans were centrally rated at Massachusetts General Hospital (Boston, MA, USA) for haemorrhagic and non-haemorrhagic CAA markers, and brain tissue samples were rated by neuropathologists at the contributing sites. We derived the Boston criteria version 2.0 (v2.0) by selecting MRI features to optimise diagnostic specificity and sensitivity in a prespecified derivation cohort (Boston cases 1994-2012, n=159), then externally validated the criteria in a prespecified temporal validation cohort (Boston cases 2012-18, n=59) and a geographical validation cohort (non-Boston cases 2004-18; n=123), comparing accuracy of the new criteria to the currently used modified Boston criteria with histopathological assessment of CAA as the diagnostic standard. We also assessed performance of the v2.0 criteria in patients across all cohorts who had the diagnostic gold standard of brain autopsy.

FINDINGS

The study protocol was finalised on Jan 15, 2017, patient identification was completed on Dec 31, 2018, and imaging analyses were completed on Sept 30, 2019. Of 401 potentially eligible patients presenting to Massachusetts General Hospital, 218 were eligible to be included in the analysis; of 160 patient datasets from other centres, 123 were included. Using the derivation cohort, we derived provisional criteria for probable CAA requiring the presence of at least two strictly lobar haemorrhagic lesions (ie, intracerebral haemorrhages, cerebral microbleeds, or foci of cortical superficial siderosis) or at least one strictly lobar haemorrhagic lesion and at least one white matter characteristic (ie, severe visible perivascular spaces in centrum semiovale or white matter hyperintensities in a multispot pattern). The sensitivity and specificity of these criteria were 74·8% (95% CI 65·4-82·7) and 84·6% (71·9-93·1) in the derivation cohort, 92·5% (79·6-98·4) and 89·5% (66·9-98·7) in the temporal validation cohort, 80·2% (70·8-87·6) and 81·5% (61·9-93·7) in the geographical validation cohort, and 74·5% (65·4-82·4) and 95·0% (83·1-99·4) in all patients who had autopsy as the diagnostic standard. The area under the receiver operating characteristic curve (AUC) was 0·797 (0·732-0·861) in the derivation cohort, 0·910 (0·828-0·992) in the temporal validation cohort, 0·808 (0·724-0·893) in the geographical validation cohort, and 0·848 (0·794-0·901) in patients who had autopsy as the diagnostic standard. The v2.0 Boston criteria for probable CAA had superior accuracy to the current Boston criteria (sensitivity 64·5% [54·9-73·4]; specificity 95·0% [83·1-99·4]; AUC 0·798 [0·741-0854]; p=0·0005 for comparison of AUC) across all individuals who had autopsy as the diagnostic standard.

INTERPRETATION

The Boston criteria v2.0 incorporate emerging MRI markers of CAA to enhance sensitivity without compromising their specificity in our cohorts of patients aged 50 years and older presenting with spontaneous intracerebral haemorrhage, cognitive impairment, or transient focal neurological episodes. Future studies will be needed to determine generalisability of the v.2.0 criteria across the full range of patients and clinical presentations.

FUNDING

US National Institutes of Health (R01 AG26484).

Effect of an individualized versus standard blood pressure management during mechanical thrombectomy for anterior ischemic stroke: the DETERMINE randomized controlled trial

Background

Hypotension and blood pressure (BP) variability during endovascular therapy (EVT) for acute ischemic stroke (AIS) due to an anterior large vessel occlusion (LVO) is associated with worse outcomes. However, the optimal BP threshold during EVT is still unknown given the lack of randomized controlled evidence. We designed the DETERMINE trial to assess whether an individualized BP management during EVT could achieve better functional outcomes compared to a standard BP management.

Methods

The DETERMINE trial is a multicenter, prospective, randomized, controlled, open-label, blinded endpoint clinical trial (PROBE design). AIS patients with a proximal anterior LVO are randomly assigned, in a 1:1 ratio, to an experimental arm in which mean arterial pressure (MAP) is maintained within 10% of the first MAP measured before EVT, or a control arm in which systolic BP (SBP) is maintained within 140–180 mm Hg until reperfusion is achieved or artery closure in case of EVT failure. The primary outcome is the rate of favorable functional outcomes, defined by a modified Rankin Scale (mRS) between 0 and 2 at 90 days. Secondary outcomes include excellent outcome and ordinal analysis of the mRS at 90 days, early neurological improvement at 24 h (National Institutes of Health Stroke Scale), final infarct volume, symptomatic intracranial hemorrhage rates, and all-cause mortality at 90 days. Overall, 432 patients will be included.

Discussion

DETERMINE will assess the clinical relevance of an individualized BP management before reperfusion compared to the one size fits all approach currently recommended by international guidelines.

Trial registration

ClinicalTrials.gov, NCT04352296. Registered on 20th April 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06538-9.

Diagnostic utility of T2*-weighted GRE in migraine with aura attack. The cortical veins sign

OBJECTIVE

To evaluate the frequency, distribution, and clinical associations of the dilated appearance of cerebral cortical veins, termed cortical veins sign on T2*-weighted gradient recalled-echo (T2*-GRE) in the acute setting of migraine with aura attack in adult patients.

METHODS

We conducted a retrospective analysis of 60 consecutive patients admitted for acute neurological symptoms with a final diagnosis of migraine with aura (42%) or probable migraine with aura (58%) who underwent emergency brain magnetic resonance imaging and 60 non-migrainous control adults. The cortical veins sign was defined as a marked hypo-intensity and/or an apparent increased diameter of at least one cortical vein. We examined the prevalence, the spatial distribution, and the associations of cortical veins sign with clinical characteristics of migraine with aura.

RESULTS

We detected the cortical veins sign in 25 patients (42%) with migraine with aura, compared to none in the control group (p < 0.0001). The spatial distribution of cortical veins sign was characterised by the predominantly bilateral and posterior location. Presence of cortical veins sign was associated with increased severity of aura (p = 0.05), and shorter delay to MRI (p = 0.02).

CONCLUSION

In the setting of acute neurological symptoms, the presence of cortical veins sign is frequent in patients with migraine with aura and can be detected with good reliability. This imaging marker may help clinicians identify underlying migraine with aura.

Rebleeding After Aneurysmal Subarachnoid Hemorrhage in Two Centers Using Different Blood Pressure Management Strategies

Background

High systolic blood pressure (SBP) after aneurysmal subarachnoid hemorrhage (aSAH) has been associated with an increased risk of rebleeding. It remains unclear if an SBP lowering strategy before aneurysm treatment decreases this risk without increasing the risk of a delayed cerebral ischemia (DCI). Therefore, we compared the rates of in-hospital rebleeding and DCI among patients with aSAH admitted in two tertiary care centers with different SBP management strategies.

Methods

Retrospective cohort study. Consecutive patients from Utrecht and Toulouse admitted within 24 h after the aSAH onset were enrolled. In Toulouse, the target SBP before aneurysm treatment was ≤140 mm Hg, while, in Utrecht, an increased SBP was only treated in extreme situations. We compared SBP levels, the incidence of rebleeding within 24 h after admission, and DCI during hospitalization.

Results

We enrolled 373 patients in Utrecht and 149 in Toulouse. The mean SBP on admission was similar but lower in Toulouse 4 h after admission (127.3 ± 17.4 vs. 138. ± 25.7 mmHg; p < 0.0001). After a median delay of 3.7 h (IQR, 2.3-7.4) from admission, 4 patients (3%) in Toulouse vs. 29 (8%) in Utrecht experienced a rebleeding. After adjustment for Prognosis on Admission of Aneurysmal Subarachnoid Hemorrhage (PAASH) score, aneurysm size, age, and delay from ictus to admission, the HR was 0.66 (95% CI: 0.23-1.92). Incidence of DCI was 18% in Toulouse and 25% in Utrecht (adjusted OR, 0.68; 95% CI: 0.41-1.11).

Conclusion

Our results suggest that an intensive SBP lowering strategy between admission and aneurysm treatment does not decrease the risk of rebleeding and does not increase the risk of DCI compared to a more conservative strategy.

Transient Focal Neurological Events in Cerebral Amyloid Angiopathy and the Long-term Risk of Intracerebral Hemorrhage and Death: A Systematic Review and Meta-analysis

Importance

Transient focal neurological episodes (TFNEs) are a frequently overlooked presentation of cerebral amyloid angiopathy (CAA), a condition with prognostic implications that are still not well described.

Objective

To perform a systematic review and meta-analysis to examine the factors associated with incident lobar intracerebral hemorrhage (ICH) and death in patients with CAA presenting with TFNEs.

Data Sources

A systematic review and individual participant meta-analysis including (1) a hospital-based cohort and (2) the results obtained from a systematic search performed in MEDLINE and Embase completed in December 2019.

Study Selection

Included studies were observational reports of TFNEs. Patient-level clinical, imaging, and prognostic data were required for inclusion. For aggregate data studies, patient-level data were requested. Disagreements were resolved by consensus.

Data Extraction and Synthesis

Data were extracted following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines by 4 independent reviewers. The quality of reports was determined based on the modified Pearson Case Report Quality Scale.

Main Outcomes and Measures

The clinical characteristics of TFNEs, neuroimaging features, and use of antithrombotics during follow-up were considered exposures. The predefined main outcomes were lobar ICH and risk of death during follow-up.

Results

Forty-two studies and 222 CAA-associated TFNE cases were included from the initial 1612 records produced by the systematic search; 26 additional patients (11 men [42.3%]; mean [SD] age, 77 [8] years) were provided by the hospital-based cohort. A total of 108 TFNEs (43.5%) consisted of motor symptoms. Convexity subarachnoid hemorrhage and cortical superficial siderosis were detected in 193 individuals (77.8%) and 156 individuals (62.9%) in the systematic search and hospital-based cohort, respectively. Follow-up duration could be obtained in 185 patients (median duration, 1 year [IQR, 0.8-2.5 years]). During follow-up, symptomatic lobar ICH occurred in 76 patients (39.4%). Motor symptoms (odds ratio, 2.08 [95% CI, 1.16-3.70]) at baseline and antithrombotic use during follow-up (odds ratio, 3.61 [95% CI, 1.67-7.84]) were associated with an increase in risk of lobar ICH. A total of 31 patients (16.5%) died during follow-up; lobar ICH during follow-up and cortical superficial siderosis were the main risk factors for death (odds ratio, 3.01 [95% CI, 1.36-6.69]; odds ratio, 3.20 [95% CI, 1.16-8.91], respectively).

Conclusions and Relevance

Patients presenting with CAA-associated TFNEs are at high risk of lobar ICH and death. Motor TFNEs and use of antithrombotics after a TFNE, in many cases because of misdiagnosis, are risk factors for ICH, and therefore accurate diagnosis and distinguishing this condition from transient ischemic attacks is critical.

What predicts poor outcome after successful thrombectomy in early time window?

BACKGROUND

Half of the patients with large vessel occlusion (LVO)-related acute ischemic stroke (AIS) who undergo endovascular reperfusion are dead or dependent at 3 months. We hypothesize that in addition to established prognostic factors, baseline imaging profile predicts outcome among reperfusers.

METHODS

Consecutive patients receiving endovascular treatment (EVT) within 6 hours after onset with Thrombolysis In Cerebral Infarction (TICI) 2b, 2c and 3 revascularization were included. Poor outcome was defined by a modified Rankin scale (mRS) 3-6 at 90 days. No mismatch (NoMM) profile was defined as a mismatch (MM) ratio ≤1.2 and/or a volume <10 mL on pretreatment imaging.

RESULTS

187 patients were included, and 81 (43%) had a poor outcome. Median delay from stroke onset to the end of EVT was 259 min (IQR 209-340). After multivariable logistic regression analysis, older age (OR 1.26, 95% CI 1.06 to 1.5; p=0.01), higher National Institutes of Health Stroke Scale (NIHSS) (OR 1.15, 95% CI 1.06 to 1.25; p<0.0001), internal carotid artery (ICA) occlusion (OR 3.02, 95% CI 1.2 to 8.0; p=0.021), and NoMM (OR 4.87, 95% CI 1.09 to 22.8; p=0.004) were associated with poor outcome. In addition, post-EVT hemorrhage (OR 3.64, 95% CI 1.5 to 9.1; p=0.04) was also associated with poor outcome.

CONCLUSIONS

The absence of a penumbra defined by a NoMM profile on baseline imaging appears to be an independent predictor of poor outcome after reperfusion. Strategies aiming to preserve the penumbra may be encouraged to improve these patients' outcomes.

Case Report: Successful Cerebral Revascularization and Cardiac Transplant in a 16-Year-Old Male With Syndromic BRCC3-Related Moyamoya Angiopathy

Background:BRCC3/MTCP1 deletions are associated with a rare familial moyamoya angiopathy with extracranial manifestations.

Case: We report the case of an adolescent male presenting with progressive and symptomatic moyamoya angiopathy and severe dilated cardiomyopathy caused by a hemizygous deletion of BRCC3/MTCP1. He was treated for renovascular hypertension by left kidney homograft and right nephrectomy in infancy and had other syndromic features, including cryptorchidism, growth hormone deficiency, and facial dysmorphism. Due to worsening of the neurological and cardiac condition, he was treated by a direct superficial temporal artery to middle cerebral artery bypass to enable successful cardiac transplant without cerebral damage.

Conclusions:BRCC3-related moyamoya is a devastating disease with severe heart and brain complications. This case shows that aggressive management with cerebral revascularization to allow cardiac transplant is feasible and efficient despite end-stage heart failure.

Interhemispheric distribution of amyloid and small vessel disease burden in cerebral amyloid angiopathy-related intracerebral hemorrhage

BACKGROUND AND PURPOSE

Intracerebral hemorrhage (ICH) is a devastating presentation of cerebral amyloid angiopathy (CAA), but the mechanisms leading from vascular amyloid deposition to ICH are not well known. Whether amyloid burden and magnetic resonance imaging (MRI) markers of small vessel disease (SVD) are increased in the ICH-affected hemisphere compared to the ICH-free hemisphere in patients with a symptomatic CAA-related ICH was investigated.

METHODS

Eighteen patients with CAA-related ICH and 18 controls with deep ICH who underwent brain MRI and amyloid positron emission tomography using ¹⁸ F-florbetapir were prospectively enrolled. In each hemisphere amyloid uptake using the standardized uptake value ratio and the burden of MRI markers of SVD including cerebral microbleeds, chronic ICH, cortical superficial siderosis, white matter hyperintensities and lacunes were evaluated. Interhemispheric comparisons were assessed by non-parametric matched-pair tests within each patient group.

RESULTS

Amyloid burden was similarly distributed across the brain hemispheres in patients with CAA-related ICH (standardized uptake value ratio 1.11 vs. 1.12; P = 0.74). Cortical superficial siderosis tended to be more common in the ICH-affected hemisphere compared to the ICH-free hemisphere (61% vs. 33%; P = 0.063). Other MRI markers of SVD did not differ across brain hemispheres. In controls with deep ICH, no interhemispheric difference was observed either for amyloid burden or for MRI markers of SVD.

CONCLUSIONS

Brain hemorrhage does not appear to be directly linked to amyloid burden in patients with CAA-related ICH. These findings provide new insights into the mechanisms leading to hemorrhage in CAA.

Abstract 2: French Acute Cerebral Multimodal Imaging to Select Patients for Mechanical Thrombectomy Final Results

Introduction: Target mismatch (TMM) identifies salvageable penumbra independent of time from stroke onset. Current guidelines do not recommend advanced imaging to select patients for mechanical thrombectomy (MT) within 6 hours after onset but indicate that more research is needed. To address this question, we designed a prospective multicenter cohort study to compare the rate of functional neurological recovery (mRS ≤2 @ 3 months) in patients treated by MT for ICA/M1/M2 occlusions within 6 hours after onset according to the presence of a TMM on baseline imaging.

Hypothesis: 60% of patients with TMM vs. 35% of no TMM, would achieve an mRS≤2 at 3 months. Sample size calculation: 200 patients.

Methods: Consecutive patients eligible for MT within 6 hrs after onset, who underwent CTP or DWI/PWI imaging before treatment were enrolled. No NIHSS or ASPECTS restrictions were applied. Treating teams were blinded of CTP/DWI/PWI maps. mRS at 3 months was rated by an investigator blinded to clinical/imaging/treatment information. Automatically processed maps by RAPID software were reviewed after the end of follow-up. TMM definition followed EXTEND-IA criteria: MM volume >10mL, MM ratio>1.2, Core volume <70 mL. Mismatch (MM) was defined by MM ratio>1.2 and MM volume>10 mL. Imaging-based subgroups (TMM vs. No TMM) were defined after the end of follow-up.

Results: 218 patients were enrolled. Baseline imaging profile distribution was 71% TMM, 29% no TMM, (in the no TMM group, 76% had a core volume > 70 mL); 82% MM and 18% no MM. Reperfusion(TICI 2B-3) was achieved in 86% of the patients after a median delay of 4.4 hrs (95%CI 3.6-5.9). 61% of the patients in the TMM group vs. 35% in the no TMM group had an mRS ≤2 @ 3 months, p<0.001 (adjustment for age, onset to reperfusion, NIHSS, reperfusion and baseline imbalances). Reperfusion vs. no reperfusion was associated with an increased rate of good outcome in the TMM and MM groups (61% vs. 38% p=0.039 and 60% vs. 32%, p=0.016) but not in the no TMM or No MM groups (35% vs. 33%, NS; 35 vs. 45%., NS).

Conclusion: Patients with salvageable penumbra on advanced imaging experienced a larger benefit from MT than those without. Patients with no penumbra did not appear to benefit from reperfusion.

Decreased frontal white-matter diffusion and improved cognitive flexibility after burr-hole surgery in moyamoya angiopathy

BACKGROUND

In Moyamoya Angioplasty (MMA), increased apparent diffusion coefficient (ADC) in frontal white matter (WM) with a normal appearance has been associated with frontal hypoperfusion and executive dysfunction. Multiple burr-hole surgery enables the revascularization of large frontal areas.

GOAL

To assess the effect of multiple burr-hole surgery on the ADC and cognitive functions in adults with MMA.

METHODS

ADC was measured in 26 brain hemispheres of 14 consecutive adults with MMA (9 women, mean age ± SD: 38.1 ± 10.7 years) prior to and 6 months after burr-hole surgery. ADC was obtained from regions of interest located in frontal and posterior (temporo-occipital) normal-appearing WM. Ten patients had neuropsychological assessment that focused on executive and attentional functions before and after surgery.

RESULTS

Anterior and posterior ADC values did not differ before surgery (815.8 ± 60.1 vs. 812.1 ± 35.3 mm²/s, p = 0.88). After surgery, frontal ADC was lower than prior to surgery (789.9 ± 64.5 vs. 815.8 ± 60.1 mm²/s; p <0.001) whereas no change occurred in posterior ADC (p = 0.31). Trail-making test part B median z-score increased from - 1.47 to - 0.21 (p = 0.018), suggesting improved cognitive flexibility.

CONCLUSION

In adults with MMA, indirect revascularization with burr-hole is followed by a decrease of ADC in normal-appearing frontal WM and may have improved some executive functions in the flexibility process. Change in ADC may reflect the improvement in cerebral perfusion after surgery. The measuring of ADC may be a promising tool in exploring potentially reversible microstructural WM damage related to hypoperfusion and cognitive change in MMA.

Underlying Small Vessel Disease Associated With Mixed Cerebral Microbleeds

Background and Purpose: Whether patients with both lobar and deep cerebral microbleeds (mixed CMB) have advanced cerebral amyloid angiopathy (CAA), hypertensive angiopathy (HA) or both is uncertain. To get insight into the underlying small vessel disease (SVD) associated with mixed CMB, we explored its association with cortical superficial siderosis (cSS), a key marker of CAA and other MRI markers of SVD in patients with intracerebral hemorrhage (ICH).

Methods: Of 425 consecutive patients with acute ICH who had received brain MRIs, 260 had ≥1 CMB and were included in the analysis. They were categorized as strictly lobar CMB (suggesting CAA), strictly deep CMB (suggesting HA) or mixed CMB. Clinical and imaging characteristics were compared (1) between the three CMB groups and (2) within mixed CMB patients according to the symptomatic ICH location.

Results: Overall, 111 (26%) patients had mixed CMB. Compared to strictly lobar CMB (n = 111) and strictly deep CMB (n = 38), patients with mixed CMB had a more severe burden of lacune, white matter hyperintensities and CMB. cSS was observed in 24.3% of patients with mixed CMB compared to 44.1% in strictly lobar CMB and 10.5% in strictly deep CMB (p < 0.0001). Among patients with mixed CMB, 44 (39.6%) had a lobar symptomatic ICH and 67 (60.4%) had a non-lobar ICH. Patients with non-lobar ICH were more likely to have hypertension, whereas those with lobar ICH were more likely to have cSS and chronic lobar ICH and had higher ratio lobar CMB count/total CMB count.

Conclusions: Mixed CMB is frequently encountered in patients with ICH and appears as a heterogeneous group, suggesting that both CAA and HA may be contributing to mixed CMB. Neuroimaging markers including ICH location, cSS, and CMB distribution may indicate the predominant underlying vasculopathy, with potential prognostic implications.

Enlarged perivascular spaces and florbetapir uptake in patients with intracerebral hemorrhage

PURPOSE

Enlarged perivascular spaces in the centrum semiovale (CSO-EPVS) have been linked to cerebral amyloid angiopathy (CAA). To get insight into the underlying mechanisms of this association, we investigated the relationship between amyloid-β deposition assessed by 18F-florbetapir PET and CSO-EPVS in patients with acute intracerebral hemorrhage (ICH).

METHODS

We prospectively enrolled 18 patients with lobar ICH (suggesting CAA) and 20 with deep ICH (suggesting hypertensive angiopathy), who underwent brain MRI and 18F-florbetapir PET. EPVS were assessed on MRI using a validated 4-point visual rating scale in the centrum semiovale and the basal ganglia (BG-EPVS). PET images were visually assessed, blind to clinical and MRI data. We evaluated the association between florbetapir PET positivity and high degree (score> 2) of CSO-EPVS and BG-EPVS.

RESULTS

High CSO-EPVS degree was more common in patients with lobar ICH than deep ICH (55.6% vs. 20.0%; p = 0.02). Eight (57.1%) patients with high CSO-EPVS degree had a positive florbetapir PET compared with 4 (16.7%) with low CSO-EPVS degree (p = 0.01). In contrast, prevalence of florbetapir PET positivity was similar between patients with high vs. low BG-EPVS. In multivariable analysis adjusted for age, hypertension, and MRI markers of CAA, florbetapir PET positivity (odds ratio (OR) 6.44, 95% confidence interval (CI) 1.32-38.93; p = 0.03) was independently associated with high CSO-EPVS degree.

CONCLUSIONS

Among patients with spontaneous ICH, high degree of CSO-EPVS but not BG-EPVS is associated with amyloid PET positivity. The findings provide further evidence that CSO-EPVS are markers of vascular amyloid burden that may be useful in diagnosing CAA.

Risk of Intracerebral Hemorrhage and Mortality After Convexity Subarachnoid Hemorrhage in Cerebral Amyloid Angiopathy

Background and Purpose- Convexity subarachnoid hemorrhage (cSAH) is an increasingly recognized presentation of cerebral amyloid angiopathy (CAA), usually revealed by transient symptoms, but data on its outcome are limited. We compared the risk of future intracerebral hemorrhage (ICH), cSAH, and death in patients with CAA after cSAH and after lobar ICH. Methods- Consecutive patients with probable CAA, based on the Boston criteria, presenting with cSAH (CAA-cSAH) or lobar ICH (CAA-ICH) were included. We obtained baseline clinical and magnetic resonance imaging data and follow-up information. Univariable and multivariable analyses were used to compare incidence rate for symptomatic ICH, symptomatic cSAH, and late-death (beyond 30 days) between patients with CAA-cSAH and CAA-ICH. Results- Among 105 patients (mean age, 76.7±7.5 years) enrolled, 44 participants presented with CAA-cSAH and 61 with CAA-ICH. The median follow-up was 22.2 months (interquartile range, 12.6-34.4). The symptomatic ICH rate (per person-year) was 10.5% (95% CI, 5.6-19.4) in patients with CAA-cSAH compared with 8.5% (95% CI, 4.4-16.4) in those with CAA-ICH (adjusted hazard ratio, 1.05; 95% CI, 0.32-3.43). The annual incidence rates of symptomatic cSAH (9.9% versus 3.8%; adjusted hazard ratio, 1.77; 95% CI, 0.43-7.28) and death (9.5% versus 17.8%; adjusted hazard ratio, 0.56; 95% CI, 0.22-1.43) were not significantly different between patients with CAA-cSAH and those with CAA-ICH. Conclusions- Patients with CAA-related cSAH have a poor outcome, with similar high risk of future ICH and long-term mortality than CAA patients after lobar ICH. Our findings may have important prognostic implication and guide management of patients with cSAH in CAA.

Subarachnoid and Subdural Hemorrhages in Lobar Intracerebral Hemorrhage Associated With Cerebral Amyloid Angiopathy

Background and Purpose- Identifying underlying cerebral amyloid angiopathy (CAA) in patients with intracerebral hemorrhage (ICH) has important clinical implication. Convexity subarachnoid hemorrhage (cSAH) and subdural hemorrhage (SDH) are computed tomography features of CAA-related ICH. We explored whether cSAH and SDH could be additional magnetic resonance imaging markers of CAA in lobar ICH survivors. Methods- We analyzed data from consecutive patients with acute lobar ICH associated with CAA (CAA-ICH) or not attributed to CAA (non-CAA-ICH). Magnetic resonance imaging scans were analyzed for cSAH, SDH, and markers of small vessel disease. The associations of cSAH and SDH with the diagnosis of probable CAA based on the modified Boston criteria were explored using multivariable models. Results- We included 165 patients with acute lobar ICH (mean age 70±13 years): 72 patients with CAA-ICH and 93 with non-CAA-ICH. Patients with CAA-ICH had a higher prevalence of cSAH (73.6% versus 39.8%; P<0.001) and SDH (37.5% versus 21.5%; P=0.02) than non-CAA-ICH. In multivariate logistic regression analysis, the presence of cSAH was independently associated with CAA-ICH (odds ratio, 2.97; 95% CI, 1.26-6.99; P=0.013), whereas there was no association between SDH and CAA-ICH. Conclusions- Among survivors of acute lobar ICH, the presence of cSAH is associated with the magnetic resonance imaging-based diagnosis of CAA. Further studies should investigate whether cSAH help improve the sensitivity of magnetic resonance imaging for in vivo diagnosis of CAA.

Acute ischaemic lesions are associated with cortical superficial siderosis in spontaneous intracerebral hemorrhage

BACKGROUND AND PURPOSE

Diffusion-weighted imaging (DWI) commonly detects acute ischaemic lesions in patients with acute intracerebral hemorrhage (ICH), especially with cerebral amyloid angiopathy (CAA). We investigated the relationship between cortical superficial siderosis (cSS), a neuroimaging marker of CAA, and DWI lesions in patients with acute ICH.

METHODS

We conducted a retrospective analysis of prospectively collected data from consecutive patients with acute supratentorial ICH who underwent brain magnetic resonance imaging within 10 days after symptom onset. Magnetic resonance imaging scans were analyzed for DWI lesions, cSS and other markers for small-vessel disease. Univariate and multivariate analyses were performed to assess the association between cSS and DWI lesions.

RESULTS

Among 246 ICH survivors (mean age 71.4 ± 12.6 years) who were enrolled, 126 had lobar ICH and 120 had deep ICH. Overall, DWI lesions were observed in 38 (15.4%) patients and were more common in patients with lobar ICH than deep ICH (22.2% vs. 8.3%; P = 0.003). In multivariate logistic regression analysis, the extent of white matter hyperintensities [odds ratio (OR), 1.29; 95% confidence interval (CI), 1.05-1.58; P = 0.02] and cSS severity (focal cSS: OR, 3.54; 95% CI, 1.28-9.84; disseminated cSS: OR, 4.41; 95% CI, 1.78-10.97; P = 0.001) were independently associated with the presence of DWI lesions.

CONCLUSIONS

Diffusion-weighted imaging lesions are more frequently observed in patients with acute lobar ICH than in those with deep ICH. cSS severity and white matter hyperintensity extent are independent predictors for the presence of DWI lesions, suggesting that CAA may be involved in the pathogenesis of DWI lesions associated with acute ICH.

Cognitive Functions in Children and Adults with Moyamoya Vasculopathy: A Systematic Review and Meta-Analysis

Background and Purpose

Patients with moyamoya vasculopathy (MMV) may experience cognitive impairment, but its reported frequency, severity, and nature vary. In a systematic review and metaanalysis, we aimed to assess the presence, severity, and nature of cognitive impairments in children and adults with MMV.

Methods

We followed the MOOSE guidelines for meta-analysis and systematic reviews of observational studies. We searched Ovid Medline and Embase for studies published between January 1, 1969 and October 4, 2016. Independent reviewers extracted data for mean intelligence quotient (IQ) and standardized z-scores for cognitive tests, and determined percentages of children and adults with cognitive deficits, before and after conservative or surgical treatment. We explored associations between summary measures of study characteristics and cognitive impairments by linear regression analysis.

Results

We included 17 studies (11 studies reporting on 281 children, six on 153 adults). In children, the median percentage with impaired cognition was 30% (range, 13% to 67%); median IQ was 98 (range, 71 to 107). Median z-score was –0.39 for memory, and –0.43 for processing speed. In adults, the median percentage with impaired cognition was 31% (range, 0% to 69%); median IQ was 95 (range, 94 to 99). Median z-scores of cognitive domains were between –0.9 and –0.4, with multiple domains being affected. We could not identify determinants of cognitive impairment.

Conclusions

A large proportion of children and adults with MMV have cognitive impairment, with modest to large deficits across various cognitive domains. Further studies should investigate determinants of cognitive deficits and deterioration, and the influence of revascularization treatment on cognitive functioning.

Abstract TP220: TIA Referral Influences Delay of Evaluation in TIA Clinic

Background: Transient ischemic attacks and minor stroke are vascular emergencies associated with a high risk of brain infarction within the first hours after onset. When available those patients may be evaluated and managed in a TIA clinic. Several therapeutic strategies are currently tested within 12 hrs after TIA/minor stroke onset. We aim to investigate the factors associated with a delay of evaluation longer than 12 hours in our TIA clinic.

Subjects and Methods: Subjects are consecutive patients evaluated in an academic center TIA clinic during 2 years. Briefly patients were evaluated by a certified stroke neurologist according to 2009 AHA recommendations including MRI, vessel imaging, blood tests, EKG and when needed TTE/TEE. Referring pathways were dichotomized between office based physicians (General practitioners, others:cardiologists, ophtalmologists, ...) and Emergency medical service (local and from other hospital with no neurologists). Univariate and multivariate logistic regression were performed.

Results: 354 patients were evaluated in 2 years. Mean (+/- SD) age was 61 YO (18), Median (IQR) ABCD2 score was 3 (2-4); median (IQR) delay from onset to evaluation was 8 hours (4-48), 59% of patients did arrive in TIA clinic within 12 hours after onset. 52% were referred by an office based physician (36% general practitioner and 16% others) vs. 48% by ED (32%,local ED and EMS 16% other ED) Univariate analysis showed that ABCD2 score<4 and office based physician referral were associated with a delay>12 hrs. There was no relationships with other factors such as risk factors, previous history of stroke or recurrent TIA. Office based physician referral was the only independent factor associated with a delay of evaluation > 12 hrs OR 5.7, (95%CI:3.5-9.3, p<0.0001) after multivariate logistic regression.

Conclusion: Direct referral from ED increases the rate of patients starting their evaluation in TIA clinic within 12 hrs after onset.

Cortical superficial siderosis and acute convexity subarachnoid hemorrhage in cerebral amyloid angiopathy

BACKGROUND AND PURPOSE

Acute convexity subarachnoid hemorrhage (cSAH) and cortical superficial siderosis (cSS) are neuroimaging markers of cerebral amyloid angiopathy (CAA) that may arise through similar mechanisms. The prevalence of cSS in patients with CAA presenting with acute cSAH versus lobar intracerebral hemorrhage (ICH) was compared and the physiopathology of cSS was explored by examining neuroimaging associations.

METHODS

Data from 116 consecutive patients with probable CAA (mean age, 77.4 ± 7.3 years) presenting with acute cSAH (n = 45) or acute lobar ICH (n = 71) were retrospectively analyzed. Magnetic resonance imaging scans were analyzed for cSS and other imaging markers. The two groups' clinical and imaging data were compared and the associations between cSAH and cSS were explored.

RESULTS

Patients with cSAH presented mostly with transient focal neurological episodes. The prevalence of cSS was higher amongst cSAH patients than amongst ICH patients (88.9% vs. 57.7%; P < 0.001). In multivariable logistic regression analysis, focal [odds ratio (OR) 6.73; 95% confidence interval (CI) 1.75-25.81; P = 0.005] and disseminated (OR 11.68; 95% CI 3.55-38.35; P < 0.001) cSS were independently associated with acute cSAH, whereas older age (OR 0.93; 95% CI 0.87-0.99; P = 0.025) and chronic lobar ICH count (OR 0.45; 95% CI 0.25-0.80; P = 0.007) were associated with acute lobar ICH.

CONCLUSIONS

Amongst patients with CAA, cSS is independently associated with acute cSAH. These findings suggest that cSAH may be involved in the pathogenesis of the cSS observed in CAA. Longitudinal studies are warranted to assess this potential causal relationship.

Acute Convexity Subarachnoid Hemorrhage Related to Cerebral Amyloid Angiopathy: Clinicoradiological Features and Outcome

BACKGROUND

The specificities of acute convexity subarachnoid hemorrhage (cSAH) related to cerebral amyloid angiopathy (CAA) and its evolution are not well known. We aimed to describe the clinicoradiological pattern, the magnetic resonance imaging (MRI) evolution, and the risk of recurrent bleeding in such patients.

METHODS

Among consecutive patients with an acute nontraumatic cSAH, subjects with available MRI who meet the modified Boston criteria for probable CAA were included. Review of medical records, MRI findings, and follow-up data was performed.

RESULTS

Twenty-three patients (14 women; mean age ± standard deviation: 75.9 ± 7.3 years) were included. cSAH was revealed by transient focal neurological episodes (TFNEs) in 18 of 23 (78.3%) patients. In all patients, acute cSAH appeared as a sulcal fluid-attenuated inversion recovery hyperintensity and GRE T2 hypointensity. Cortical superficial siderosis and cortical microbleeds, respectively, were observed in 21 (91.3%) and 20 (86.9%) patients. Twenty patients (87%) had available follow-up data with a mean duration of 29.8 ± 20.2 months. Recurrent TFNEs occurred in 40% of patients. Acute cSAH evolved into cortical superficial siderosis in all patients. New subarachnoid bleedings defined by recurrent acute cSAH (n = 8) or extension of siderosis (n = 14) were detected in 83.3% of the patients. Lobar intracerebral hemorrhage (ICH) occurred in 7 patients (35%).

CONCLUSION

CAA-related cSAH has a specific pattern defined by a high prevalence of TFNEs and cortical superficial siderosis, with a high risk of recurrent bleeding, either cSAH or lobar ICH. The systematic evolution from cSAH to focal cortical superficial siderosis reveals data on siderosis physiopathology.

Abstract WMP95: Cerebral Amyloid Angiopathy Patients With Convexity Subarachnoid Hemorrhage Present Higher Risk of Subsequent Hemorrhage Than Those With Lobar Intracranial Hemorrhage

Background: Acute convexity subarachnoid hemorrhage (cSAH) is increasingly recognized as a marker of cerebral amyloid angiopathy (CAA). Little is known about the risk of subsequent hemorrhage in such CAA presentation, whereas CAA-related lobar intracranial hemorrhage (ICH) is associated with a high risk of recurrence. The aim of this study was to compare clinical outcome among patients with an acute CAA related- cSAH to those with an acute CAA-related lobar ICH.

Hypothesis: We hypothesized that the risk of subsequent hemorrhage is different between patients with acute cSAH and lobar ICH related to CAA.

Methods: We retrospectively reviewed the clinical outcomes (death, subsequent transient focal neurological episodes (TFNE), rates of ICH and acute cSAH) of 45 consecutive patients (75 ± 7 years) with an acute cSAH related to probable CAA compared to 70 consecutive patients (78 ± 7 years) with an acute lobar ICH meeting the Boston criteria for probable CAA.

Results: cSAH-patients presented essentially with TFNE (84.4% vs 0%; p<0.001) whereas ICH-patients had a persistent neurological deficit (98.6% vs 15.6%; p<0.001). Five patients with lobar ICH died in the first days. Thirty nine cSAH-patients and 60 lobar ICH-patients had available follow-up data. The mean time of follow-up (± SD) was 364 ± 358 days. Mortality did not differ between cSAH-patients and ICH-patients who survived (10.2 % vs 16.7%; p = 0.38). Patients with cSAH had a higher rate of TFNE (48.7 % vs 0 %; p<0.001) and acute cSAH recurrence (20.5 % vs 1.7 %; p = 0.002). In the other hand, 20.5 % of cSAH-patients presented a subsequent ICH, not different from patients with acute ICH (15.0 %; p = 0.45).

Conclusions: In the context of CAA, patients with acute cSAH present more clinical recurrences than lobar ICH-patients, due to higher risk of subsequent TFNE and acute cSAH. Although the clinical presentation of cSAH-patients may appear benign, their outcome regarding the risk of incident ICH and mortality, does not seem different from CAA-related lobar ICH survivors.

Abstract WP362: Subarachnoid and Subdural Hemorrhages Concomitant to Acute Lobar Intracerebral Hematoma are Markers of Cerebral Amyloid Angiopathy

Background: Convexity subarachnoid hemorrhage (cSAH) or subdural Hematoma (SDH) are occasionally described on CT or MRI in the area of acute lobar intracerebral hematoma (ICH). The prevalence and the etiologic significance of this association are not well known.

Hypothesis: We hypothesized that cSAH and SDH were more frequent in Cerebral Amyloid Angiopathy (CCA)-related lobar ICH.

Methods: Using our electronic database, we retrospectively reviewed the clinical and MRI characteristics of 165 consecutive patients (mean age 70 ± 13 years) admitted for acute lobar ICH. The presence of cSAH and SDH was assessed by 2 reviewers on a brain MRI performed within 10 days after ICH onset.

Results: SDH and cSAH were present in respectively 28.5 and 54.5 % of all patients. Among patients with acute lobar ICH meeting the modified Boston criteria for probable CAA, the frequency was 37.5 % (27/72) for SDH and 73 % (53/72) for cSAH, which is significantly higher than among patients with hematoma of other causes ( 21.5 and 39.8 %; p=0.03 and p<0.001 respectively). The association remained significant considering patients meeting the modified Boston criteria for probable or possible CAA versus others causes.

Conclusions: Using MRI for evaluation of acute lobar ICH, cSAH and SDH were very frequent and associated with CCA. This is consistent with the involvement of leptomeningeal arteries in this disease. The presence of subarachnoid or subdural hemorrhage should be systematically assessed and could be added to diagnostic criteria for CAA.

Abstract WMP93: Cortical Superficial Siderosis in Cerebral Amyloid Angiopathy: Higher Prevalence Among Convexity Subarachnoid Hemorrhage Than Among Intracerebral Hemorrhage

Introduction: Cerebral amyloid angiopathy (CAA) is a major cause of both lobar intracerebral hemorrhage (ICH) and cerebral microbleeds (CMB), especially in the elderly. Recently, acute convexity subarachnoid hemorrhage (cSAH) and cortical superficial siderosis (cSS) has been identified as markers of CAA. Although the clinical feature and the increased risk of future lobar ICH of cSS is well established, little is known about the specific pattern of CAA-related cSAH.

Hypothesis: We hypothesized that clinical and imaging characteristics of CAA-related cSAH differ from CAA-related lobar ICH.

Methods: We retrospectively analyzed clinical and MRI data of a monocentric cohort of 45 consecutive patients with an acute cSAH related to probable CAA and a comparison group of 70 consecutive patients presenting with an acute lobar ICH meeting Boston criteria for probable CAA.

Results: cSAH patients were younger than ICH patients (mean age +/-SD: 75 +/-7 vs 78 +/-7; p=0.046). Transient focal neurological episodes (TFNE) were common among cSAH patients (84.4% vs 0%; p<0.001). Persistent focal neurological deficits were frequent among ICH patients (15.6% vs 98.6%; p<0.001). Prevalence of cSS was significantly higher among cSAH patients than among ICH patients (88.9% vs 60%; p<0.001) especially disseminated (66.7% vs 37.1%; p=0.002) and bilateral cSS (48.9% vs 28.6%; p=0.027). Number of lobar macrobleeds (median number [IQR]: 0 [0-1] vs 1[1-2]; p=0.07) and lobar CMB (median number [IQR]: 3 [1-6] vs 6 [2-14.75]; p=0.405) did not differ between the two groups.

Conclusions: In CAA, patients presenting with cSAH are characterized by a younger age, TFNE as presenting symptoms and a higher prevalence of cSS than those presenting with Lobar ICH. These findings suggest that restricted hemorrhage into the subarachnoid space may play a crucial role in cSS physiopathology.

Research Progresses in Understanding the Pathophysiology of Moyamoya Disease

BACKGROUND

The pathogenesis of moyamoya disease (MMD) is still unknown. The detection of inflammatory molecules such as cytokines, chemokines and growth factors in MMD patients' biological fluids supports the hypothesis that an abnormal angiogenesis is implicated in MMD pathogenesis. However, it is unclear whether these anomalies are the consequences of the disease or rather causal factors as well as these mechanisms remain insufficient to explain the pathophysiology of MMD. The presence of a family history in about 9-15% of Asian patients, the highly variable incidence rate between different ethnic and sex groups and the age of onset support the role of genetic factors in MMD pathogenesis. However, although some genetic loci have been associated with MMD, few of them have been replicated in independent series. Recently, RNF213 gene was shown to be strongly associated with MMD occurrence with a founder effect in East Asian patients. However, the mechanisms leading from RNF213 mutations to MMD clinical features are still unknown.

SUMMARY

The research on pathogenic mechanism of MMD is in its infancy. MMD is probably a complex and heterogeneous disorder, including different phenotypes and genotypes, in which more than a single factor is implicated.

KEY MESSAGE

Since the diagnosis of MMD is rapidly increasing worldwide, the development of more efficient stratifying risk systems, including both clinical but also biological drivers became imperative to improve our ability of predict prognosis and to develop mechanism-tailored interventions.

Abstract TP425: Clinical and Radiological Spectrum of Nontraumatic Cortical Subarachnoid Hemorrhages : A Consecutive Series of 62 Patients

Non-traumatic cortical subarachnoid hemorrhage (cSAH) is an unusual location of SAH not related to aneurysmal rupture. Several causes have been described in small cohorts. We report the characteristics and the follow-up of a large cohort of such patients.

Methods: During 4 years, consecutive patients admitted in our institution with a cSAH revealed by neurological symptoms were included in a registry. Retrospective review of medical records, neuroimaging studies, and follow-up data was performed.

Results: Sixty two patients (37 women; mean age ± SD : 66 ± 14 years) were included. The main clinical presentation was a transient deficit in 50 % of cases. Headache was present in only 39 % of cases. Cerebral amyloid angiopathy (CAA) accounted for 50 % of cases. The main other etiologies were reversible vasoconstriction syndrome (13 %), endocarditis (11 %), severe intracranial or cervical arterial stenoses (8 %) and cerebral venous thrombosis (5 %). Patients with CAA were older (p < 0.001) and suffered essentially from transient deficit (80 vs 18 %; p < 0.001) without headache (18 % vs 58 %; p = 0.002). Cortical hemosiderosis on MRI was strongly associated with CAA (77 % vs 0 %; p < 0.001). Follow up data were available in 55 patients (28 with CAA). Forty eight patients underwent an imaging follow up (25 with CAA). Recurrent hemorrhages (cSAH or hematoma) occurred in 52 % of CAA cases against 12 % in other origins (p = 0.01).

Conclusions: Our data show that CCA is clearly the main etiology of cSAH with a specific pattern associating transient neurological deficit without headache and cortical hemosiderosis on MRI. Many origins can be found in younger patients to whom the diagnosis is guided by imaging findings and clinical background. The risk of recurrence is high in CAA contrary to other etiologies.

Abstract 55: Prediction of Delayed Cerebral Ischemia After Subarachnoid Hemorrhage Using Variations of Dynamic Cerebral Autoregulation

The risk of delayed cerebral ischemia (DCI) after cerebral aneurysm rupture is increased in patients with large cerebral artery vasospasm (VS). The predictive value of VS is, however, far to be optimal. Assessment of cerebral microcirculation impairment using dynamic cerebral autoregulation (DCA) measurement might improve our ability to predict DCI in these patients.

Methods. We included consecutive patients with low-grade aneurysmal subarachnoid hemorrhage (SAH) (WFNS 1 to 3) within 4 days of aneurysm rupture. DCA was evaluated using the moving correlation coefficient Mx calculated from spontaneous fluctuations of cerebral blood flow velocities and arterial blood pressure. Impairment of DCA was defined as Mx ≥ 0.3. Transcranial colour-coded sonography was performed every 48 hours to look for VS. Diagnosis of VS was based on a Lindegaard ratio >3 (MCA), or mean flow velocities > 130 cm/s (ACA). DCI was defined as neurologic deterioration caused by brain ischemia confirmed by brain imaging.

Results. Thirty patients (19 women; mean age ± SD: 44.7 ± 12.1 years) were included. Twenty (66.7%) patients had VS. DCI occurred in six (20%) patients after a median delay of 10 days (range 8 to 13 days). Mx (mean ± SD) was heightened at baseline (0.43 ± 0.2) and at day 7 (0.46 ± 0.2), then decreased at day 14 (0.37 ± 0.18 (p = 0.034). Isolated measures of VS and Mx were not associated with DCI. However, the elevation of Mx between baseline and day 7 in patients with VS was predictive of subsequent DCI (positive likelihood ratio=5.01; negative likelihood ratio=0.19; P=0.005).

Conclusion. Findings suggest that DCA assessment may help to predict better the risk of DCI after cerebral aneurysm rupture than the simple recordings of mean flow velocities.

Executive dysfunction in adults with moyamoya disease is associated with increased diffusion in frontal white matter

BACKGROUND AND PURPOSE

Alteration of the cerebrovascular reserve (CVR) in the frontal lobes has been associated with cognitive dysfunction in adults with moyamoya disease (MMD). Elevation of the apparent diffusion coefficient (ADC) in normal-appearing white matter on conventional MRI may occur as a consequence of chronic haemodynamic failure. In the present study, the authors examined the relation of ADC with CVR and cognitive dysfunction in adults with MMD.

METHODS

The authors measured ADC and CVR in the normal-appearing frontal white matter. CVR was calculated using dynamic susceptibility contrast-enhanced MRI and the acetazolamide challenge. A standardised and validated neuropsychological assessment test battery focusing on executive function was used.

RESULTS

14 patients, 9 women and 5 men (mean age 36.6±12.9 years), were included. The authors found executive dysfunction in 7 of 13 tested patients. ADC and CVR were negatively correlated (Spearman coefficient: -0.46; p=0.015). Elevation of ADC predicted executive dysfunction (area under receiver operating characteristic curve (95% CI): 0.85 (0.59 to 1.16); p=0.032).

CONCLUSION

Elevation of ADC in the normal-appearing frontal white matter of adults with MMD was associated with reduced CVR and executive dysfunction. This preliminary study suggests that measurement of ADC might be used to detect patients at risk for cerebral ischaemia and cognitive impairment.

Etiologic investigation of ischemic stroke in young adults

OBJECTIVES

We attempted to classify causes of ischemic stroke in young adults using a progressive diagnostic algorithm and the ASCO (atherosclerosis, small-vessel disease, cardiac source, other cause) classification system.

METHODS

Patients aged 16-54 years consecutively treated for acute ischemic stroke in a tertiary stroke unit were included in this retrospective analysis. Causes of stroke were classified using the ASCO system, which assigns a graded level of likelihood to each potential cause in individual patients. The initial etiologic workup included brain imaging, magnetic resonance or CT angiography of cerebral and cervical vessels, EKG, and routine blood studies. Patients without a definite cause of ischemic stroke after initial evaluation underwent transesophageal echocardiography.

RESULTS

We included 318 patients (195 men and 123 women); 131 patients were aged 16-44 years, and 187 were aged 45-54 years. A definite cause of stroke (ASCO grade 1) could be identified in 145 patients (45.5%). An uncertain cause of stroke (ASCO grade 2) was found in 59 (18.5%) further patients. Most (130 of 145) definite causes were identified by initial evaluation. The 2 major definite or uncertain causes of stroke were patent foramen ovale associated with atrial septal aneurysm (PFO-ASA) (20 of 131 [15.3%]) and dissection of the cervical or cerebral artery (19 of 131 [14.5%]) in patients aged 16-44 years and large-vessel atherosclerosis (37 of 187 [19.8%]) and PFO-ASA (23 of 187 [12.3%]) in patients aged 45-54 years.

CONCLUSIONS

Our findings suggest that PFO-ASA may be a major cause of ischemic stroke in young adults.

Improvement in cognitive function and cerebral perfusion after bur hole surgery in an adult with moyamoya disease

Recent studies have suggested that cognitive impairment may be a common complication in adults with moyamoya disease (MMD). However, the mechanisms of cognitive dysfunction have not been clarified. Whether cognitive impairment may occur as a consequence of cerebral hypoperfusion and may improve after revascularization surgery has not been determined. A 39-year-old West Indian woman with subacute dysexecutive cognitive syndrome and no history of stroke was diagnosed with MMD. Magnetic resonance imaging showed an old, small cerebral infarction in the left frontal white matter and no evidence of recent cerebral ischemia. Perfusion MR imaging with acetazolamide challenge demonstrated a reduced cerebrovascular reserve in both frontal lobes. Revascularization with bur hole surgery was performed, which resulted in complete regression of initial cognitive impairment. Improvement in cognitive function correlated with the development of transdural collaterals on angiography and improvement in cerebral perfusion on MR imaging. This case suggests a relationship between cognitive dysfunction and cerebral hypoperfusion in MMD. Cognitive impairment may be potentially reversible after bur hole surgery and cerebral perfusion improvement.

Correlation between cognitive impairment and cerebral hemodynamic disturbances on perfusion magnetic resonance imaging in European adults with moyamoya disease

Object

Although cognitive impairment has been reported in adults with moyamoya disease (MMD), its relationship with cerebral hemodynamic disturbances has not been investigated. The aims of the present study were to confirm the presence of dysexecutive cognitive syndrome (DCS) in adults with MMD and to explore the relationship of DCS with frontal lobe perfusion as measured by perfusion MR imaging.

Methods

Cerebral blood volume (CBV) ratio and mean transit time delay were measured in frontal and temporoparietal regions using the cerebellum as a reference region in 10 European adults with MMD. In addition, the authors calculated the cerebrovascular reserve (CVR) using the CBV ratio and the acetazolamide challenge. All patients underwent a standardized neuropsychological assessment test battery. The authors defined DCS as an impairment shown on 3 tests or more of executive function.

Results

The authors found DCS in 6 patients. The frontal CVR was lower in patients with DCS than in patients without DCS (mean ± SD: −13.5 ± 13.2% and 20.3 ± 21.3%; p = 0.019, Mann-Whitney U-test). Other parameters of frontal perfusion and temporoparietal CVR were not correlated with DCS.

Conclusions

The authors' findings suggest that DCS is common in European adults with MMD and may be related to frontal perfusion impairment.

Isolated acute nontraumatic cortical subarachnoid hemorrhage

Our aim was to review the etiologic background of isolated acute nontraumatic cSAH. While SAH located in the basal cisterns originates from a ruptured aneurysm in approximately 85% of cases, a broad spectrum of vascular and even nonvascular pathologies can cause acute nontraumatic SAH along the convexity. Arteriovenous malformations or fistulas, cortical venous and/or dural sinus thrombosis, and distal and proximal arteriopathies (RCVS, vasculitides, mycotic aneurysms, Moyamoya, or severe atherosclerotic carotid disease) should be sought by noninvasive imaging methods or/and conventional angiography. Additionally, PRES may also be a source of acute cSAH. In elderly patients, cSAH might be attributed to CAA if numerous hemorrhages are demonstrated by GRE T2 images. Finally, cSAH is rarely observed in nonvascular disorders, such as abscess and primitive or secondary brain tumors.