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The management of tandem extracranial internal carotid artery and intracranial large vessel occlusion during endovascular thrombectomy (EVT) for acute ischemic stroke (AIS) has been under-investigated. We sought to investigate outcomes of AIS patients with tandem occlusion (TO) treated with carotid artery stenting (CAS) compared to those not treated with CAS (no-CAS) during EVT.We performed a cohort study using data from AIS patients enrolled in the Italian Registry of Endovascular Treatment in Acute Stroke. Outcomes were 3 months' mortality, functional outcome, complete and successful recanalization, any intracranial hemorrhage, parenchymal hematoma and symptomatic intracerebral hemorrhage.Among 466 AIS patients with TO, CAS patients were 122 and no-CAS patients were 226 (118 excluded). After adjustment for unbalanced variables, CAS was associated with a lower rate of 3 months' mortality (OR 0.407, 95% CI 0.171-0.969, p = 0.042). After adjustment for pre-defined variables, CAS was associated with a lower rate of 3 months' mortality (aOR 0.430, 95% CI 0.187-0.989, p = 0.047) and a higher rate of complete recanalization (aOR 1.986, 95% CI 1.121-3.518, p = 0.019), successful recanalization (aOR 2.433, 95% CI 1.263-4.686, p = 0.008) and parenchymal hematoma (aOR 2.876, 95% CI 1.173-7.050, p = 0.021). CAS was associated with lower 3 months mortality (OR 0.373, 95% CI 0.141-0.982, p = 0.046) and higher rates of successful recanalization (OR 2.082, 95% CI 1.099-3.942, p = 0.024) after adjustment for variables associated with 3 months' mortality and successful recanalization, respectively.Among AIS patients with TO, CAS during EVT was associated with a higher rate of successful reperfusion and a lower rate of 3 months' mortality.

Introduction The present study investigates the production of inflected forms from word-stems with a regular vs. an irregular inflection. This issue has been mostly focused on the theoretical debate between Dual Mechanism theories (rule-based procedures vs. recovery of whole forms stored in an associative network, Pinker & Ullman, 2002) and Connectionist models (single procedure for both regular and irregular forms, McClelland & Patterson, 2002). The two accounts make different predictions about the neural underpinnings of lexical processing for regular and irregular verbs. The declarative/procedural model is a modular theory positing that irregular forms are recovered from the mental lexicon which depends on declarative memory and is subserved by the temporal lobe, whereas regular forms are assembled by means of a mental grammar which involves procedural memory and is subserved by the frontal cortex and the basal ganglia (Ullman, 2001). Concurrent models do not postulate a categorical difference between regular and irregular forms and suggest that different pattern of brain activations elicited by regular and irregular verbs are predicted by phonological, semantic and other probabilistic features of verbs (Joanisse & Seidenberg, 2005). However, an alternative hypothesis, mainly grounded on linguistic, behavioral and simulation data (Burzio, 1998; Bordag & Pechmann, 2009; Colombo et al., 2004; 2006; Laudanna, 2007; Laudanna et al., 2004; Pirrelli & Herreros, 2005; Verissimo & Clahsen, 2009), suggests that all inflected forms in the mental lexicon, regardless of regularity, are organized in clusters on the basis of their paradigmatic relations among word-forms other than the regular/irregular distinction and that inflectional processes are likely to be governed by membership of words to specific clusters, namely the inflectional classes. This third positions predicts the possibility to detect experimental effects driven by the membership of words to inflectional classes rather than to the coarse distinction between regular and irregular. In this study we try to shed light on the issue by exploiting a suitable test case, the Italian verb inflectional system. Here, verbs fall into one of three conjugations each exhibiting different degrees of regularity, numerosity and consistency. By using both behavioral and neuroimaging techniques, we aim at demonstrating that mechanisms underlying speaker’s ability to perform inflectional operations rely on grammatical properties of verbs depending on their membership to different inflectional classes. Methods A past-participle generation task was admnistered in a behavioral (42 participants) and an eventrelated fMRI setting (23 participants). A set of 168 Italian verbs was selected and arranged into 6 subsets of experimental stimuli on the basis of Regularity (regulars vs. irregulars) and Conjugation membership (1st vs. 2nd vs. 3rd). The six subsets were matched on frequency, length, N-count, locus and manner of articulation of the initial phoneme, syllabic structure of the initial syllable, syllabic structure of both the infinitive and past-participle form. Different sets of statistical analyses were carried out on response latencies, accuracy rates and BOLD responses. Analyses testing putative effects of Conjugation were restricetd to response Poster session 1 34 patterns only elicited by regular verbs. Analyses on response measures only elicited by 2nd and 3 rd conjugation verbs tested the interaction between Regularity and Conjugation. Results Main effects of the variable Conjugation were obtained both in the behavioural and in the fMRI experiments: 2nd conjugation regular verbs were responded significantly slower and poorer than 1 st and 3rd conjugation regular verbs. The left middle frontal gyrus and the pre-supplementary motor area exhibited a significantly higher BOLD activation response for 2nd and 3rd conjugation regular verbs than for 1st conjugation regular verbs. In addition, the analyses performed on both 2nd and 3rd conjugation regular and irregular verbs revealed that 2nd conjugation verbs were slower and less accurate than 3rd conjugation verbs and that the perigenual part of the left anterior cingulate cortex was significantly more activated for 2nd than for 3rd conjugation verbs. A main effect of Regularity was also observed: irregular verbs were slower and less accurate than regular verbs. The left prefrontal cortex and the anterior part of the left inferior frontal gyrus were found significantly more activated for irregular when compared to regular verbs. Interestingly, a significant Conjugation by Regularity interaction was observed: behaviorally, the Regularity effect was stronger for 3rd than for 2nd conjugation verbs. In the left and right postcentral gyri, the 2nd conjugation irregular verbs elicited significant weaker activation than regular ones; the 3rd conjugation verbs elicited the opposite pattern. Discussion The present study demonstrates that inflecting Italian verbs from different conjugations, irrespective of regularity, requires different cognitive operations since it elicits differences in behavioral response latencies, accuracy rates and cortical activations. Rather than a segregation between different brain structures devoted to the processing of regular and irregular verbs, different patterns of activation for both the regular and irregular verbs in the same structures were found. Differences among regular verbs belonging to different inflectional classes were also obtained both on behavioral and neural grounds. This pattern of data cannot be easily accommodated within either a dual or a single mechanism account. Dual mechanism theories postulate that all regular verbs follow symbolic inflectional rules, thereby no differences among regular verbs are expected. The observed difference cannot be ascribed neither to any formal feature as predicted by single mechanism accounts: actually, in our work we matched many formal features across the experimental categories. Our data corroborate the idea that language-specific properties of inflectional classes might modulate cognitive operations and biological underpinnings of inflectional behavior.

BackgroundThere is no consensus on the most effective endovascular technique to use in patients with acute ischemic stroke due to terminal internal carotid artery (ICA) occlusion. The aim of this study was to compare safety and efficacy of the aspiration technique (AT) and combined technique (CT) as first-line approach in terminal ICA occlusions.MethodsWe performed a retrospective analysis of prospectively collected databases from seven Italian stroke centers. Patients were divided into two subgroups according to the first-line approach: AT group or CT group. We followed the STROBE guidelines for cohort studies. We used Chi-square test, one-way and multivariate ANOVA analysis, together with contrast analysis and post hoc tests, logistic regression and Pearson’s bivariate correlation for the statistical analyses.ResultsBetween January 2018 and August 2020, 353 patients were treated for a terminal ICA occlusion, with either AT or CT. CT was associated with a higher Thrombolysis in Cerebral Infarction (TICI) 2B-3 after the first pass (51.0% vs 26.9%) and at the end of the procedure (84% vs 73.3%) and with an improved clinical outcome at discharge (modified Rankin Scale (mRs) 0–2 of 47.8% vs 34.0%) and at 3 months’ follow-up (mRs 0–2 of 56.5% vs 38.9%) compared with AT.ConclusionThrombectomy of terminal ICA occlusions obtained using CT as first-line approach demonstrated better technical and functional outcomes in comparison with AT.

INTRODUCTION: A direct aspiration first pass technique (ADAPT) is an alternative technique as first-line thrombectomy for large vessel occlusion in acute ischemic stroke, still debated when compared to first-line stent retriever. To retrospectively evaluate technical and clinical outcomes of the ADAPT as first-line treatment for anterior circulation acute ischemic stroke with large-bore reperfusion catheters. METHODS: A multicentric data collection from 14 medical centers was retrospectively analyzed. Large-bore catheters had a distal diameter between 0.64 and 0.71 in; stent retriever was added when aspiration alone failed. Baseline characteristics, technical and clinical variables were collected, including NIHSS, thrombolysis in cerebral infarction (TICI), peri-procedural complications, 90-day mRS and 90-day mortality. RESULTS: Overall, 501 patients were treated. No statistically significant difference in terms of baseline features or tPA administration was recorded between patients treated with ADAPT and with additional stent retriever. ADAPT alone was successful in achieving TICI ≥ 2b in 71.8% with a median of 1.55 aspiration attempts. In terms of TICI ≥ 2b, ADAPT alone was better than additional stent retriever (p

The generation of regular and irregular inflected verb-forms has been taken as a crucial test between models of inflection in the mental lexicon, namely approaches which invoke different mechanisms for regular and irregular forms (rule-based procedures vs. recovery of whole forms stored in an associative network) and accounts which postulate a single procedure for all forms. An alternative hypothesis suggests that inflectional processes are explained by membership of words to clusters, for instance, Italian inflectional classes (conjugations). In a behavioural and a rapid event-related fMRI experiment, participants overtly generated the past participle of verbs from the three Italian conjugations. Results showed that the cognitive operations and the neural substrate underlying inflectional processes rely on specific properties of inflectional classes. Different patterns of cortical activations elicited by verbs from different conjugations were detected for the first time in the left middle frontal gyrus, left pre-supplementary motor area and left anterior cingulate cortex.

Age-related hearing loss (HL) can be related to brain dysfunction or structural damage and may result in cerebral metabolic/perfusion abnormalities. Arterial spin labeling (ASL) magnetic resonance imaging (MRI) allows investigating noninvasively brain perfusion changes. Pseudocontinuous ASL and T1-weighted MRI (at 3 T) and neuropsychological testing (Montreal Cognitive Assessment) were performed in 31 HL (age range = 47–77 years, mean age ± SD = 63.4 ± 8.4 years, pure-tone average [PTA] HL > 50 dB) and 28 normal hearing (NH; age range = 48–78 years, mean age ± SD = 59.7 ± 7.4 years) subjects. Cerebral blood flow (CBF) and gray matter volume (GMV) were analyzed in the cortical volume to assess perfusion and structural group differences. Two HL subjects showing cognitive impairment were excluded from group comparisons. No significant differences in either global or local atrophy were detected between groups but the HL group exhibited significant regional effects of reduced perfusion within the bilateral primary auditory cortex, with maximal CBF difference (−17.2%) in the right lateral Heschl's gyrus. For the whole sample of HL and NH subjects (n = 59 = 31 HL + 28 NH), the regional CBF was correlated positively to the regional GMV (p = 0.020). In HL subjects (n = 31), the regional CBF was correlated negatively to the audiogram steepness (frequency range: 2–4 kHz, right ear: p = 0.022, left ear: p = 0.015). The observed cortical pattern of perfusion reduction suggests that neuronal metabolism can be related to HL before the recognition of brain structural damage. This also illustrates the potential of ASL-MRI to contribute early functional markers of reduced central processing associated with HL.

Quantitative MRI (qMRI) provides surrogate brain maps of myelin and iron content. After spatial normalization to a common standard brain space, these may be used to detect altered myelination and iron accumulation in clinical populations. Here, volumetric and combined volumetric and surface-based (CVS) normalization were compared to identify which procedure would afford the greatest sensitivity to inter-regional differences (contrast), and the lowest inter-subject variability (under normal conditions), of myelin- and iron-related qMRI parameters, in whole-brain group-level studies. Ten healthy volunteers were scanned twice at 3 Tesla. Three-dimensional T1-weighted, T2-weighted and multi-parametric mapping sequences for brain qMRI were used to map myelin and iron content over the whole brain. Parameter maps were spatially normalized using volumetric (DARTEL) and CVS procedures. Tissue probability weighting and isotropic Gaussian smoothing were integrated in DARTEL for voxel-based quantification (VBQ). Contrasts, coefficients of variations and sensitivity to detecting differences in the parameters were estimated in standard space for each approach on region of interest (ROI) and voxel-by-voxel bases. The contrast between cortical and subcortical ROIs with respectively different myelin and iron content was higher following CVS, compared to DARTEL-VBQ, normalization. Across cortical voxels, the inter-individual variability of myelin and iron qMRI maps were comparable between CVS (with no smoothing) and DARTEL-VBQ (with smoothing). CVS normalization of qMRI maps preserves higher myelin and iron contrast than DARTEL-VBQ over the entire brain, while exhibiting comparable variability in the cerebral cortex without extra smoothing. Thus, CVS may prove useful for detecting small microstructural differences in whole-brain group-level qMRI studies.