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The diagnosis of Moyamoya disease (MMD) relies heavily on imaging, which could benefit from standardized machine learning tools. This study aims to evaluate the diagnostic efficacy of deep learning (DL) algorithms for MMD by analyzing sensitivity, specificity, and the area under the curve (AUC) compared to expert consensus. We conducted a systematic search of PubMed, Embase, and Web of Science for articles published from inception to February 2024. Eligible studies were required to report diagnostic accuracy metrics such as sensitivity, specificity, and AUC, excluding those not in English or using traditional machine learning methods. Seven studies were included, comprising a sample of 4,416 patients, of whom 1,358 had MMD. The pooled sensitivity for common and random effects models was 0.89 (95% CI: 0.85 to 0.92) and 0.92 (95% CI: 0.85 to 0.96), respectively. The pooled specificity was 0.89 (95% CI: 0.86 to 0.91) in the common effects model and 0.91 (95% CI: 0.75 to 0.97) in the random effects model. Two studies reported the AUC alongside their confidence intervals. A meta-analysis synthesizing these findings aggregated a mean AUC of 0.94 (95% CI: 0.92 to 0.96) for common effects and 0.89 (95% CI: 0.76 to 1.02) for random effects models. Deep learning models significantly enhance the diagnosis of MMD by efficiently extracting and identifying complex image patterns with high sensitivity and specificity. Trial registration: CRD42024524998 https://www.crd.york.ac.uk/prospero/displayrecord.php?RecordID=524998., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Neurocritical patients frequently exhibit abnormalities in cerebral hemodynamics (CH) and/or intracranial compliance (ICC), all of which significantly impact their clinical outcomes. Transcranial Doppler (TCD) and the cranial micro-deformation sensor (B4C) are valuable techniques for assessing CH and ICC, respectively. However, there is a scarcity of data regarding the predictive value of these techniques in determining patient outcomes. We prospectively included neurocritical patients undergoing intracranial pressure (ICP) monitoring within the first 5 days of hospital admission for TCD and B4C assessments. Comprehensive clinical data were collected alongside parameters obtained from TCD (including the estimated ICP [eICP] and estimated cerebral perfusion pressure [eCPP]) and B4C (measured as the P2/P1 ratio). These parameters were evaluated individually as well as in combination. The short-term outcomes (STO) of interest were the therapy intensity levels (TIL) for ICP management recommended by the Seattle International Brain Injury Consensus Conference, as TIL 0 (STO 1), TIL 1-3 (STO 2) and death (STO 3), at the seventh day after last data collection. The dataset was randomly separated in test and training samples, area under the curve (AUC) was used to represent the noninvasive techniques ability on the STO prediction and association with ICP. A total of 98 patients were included, with 67% having experienced severe traumatic brain injury and 15% subarachnoid hemorrhage, whilst the remaining patients had ischemic or hemorrhagic stroke. ICP, P2/P1, and eCPP demonstrated the highest ability to predict early mortality (p = 0.02, p = 0.02, and p = 0.006, respectively). P2/P1 was the only parameter significant for the prediction of STO 1 (p = 0.03). Combining B4C and TCD parameters, the highest AUC was 0.85 to predict death (STO 3), using P2/P1 + eCPP, whereas AUC was 0.72 to identify ICP > 20 mmHg using P2/P1 + eICP. The combined noninvasive neuromonitoring approach using eCPP and P2/P1 ratio demonstrated improved performance in predicting outcomes during the early phase after acute brain injury. The correlation with intracranial hypertension was moderate, by means of eICP and P2/P1 ratio. These results support the need for interpretation of this information in the ICU and warrant further investigations for the definition of therapy strategies using ancillary tests., (© 2024. The Author(s).)

Ruptured anterior communicating artery (ACoA) aneurysms are frequently associated with neuropsychological deficits. This review aims to compare neuropsychological outcomes between surgical and endovascular approaches to ACoA. We systematically searched PubMed, Embase, and Web of Science for studies comparing the endovascular and surgical approaches to ruptured ACoA aneurysms. Outcomes of interest were the cognitive function, covered by memory, attention, intelligence, executive, and language domains, as well as motor and visual functions. Nine studies, comprising 524 patients were included. Endovascularly-treated patients showed better memory than those treated surgically (Standardized Mean Difference (SMD) = -2; 95% CI: -3.40 to -0.61; p < 0.01). Surgically clipped patients had poorer motor ability than those with coiling embolization (p = 0.01). Executive function (SMD = -0.20; 95% CI: -0.47 to 0.88; p = 0.55), language (SMD = -0.33; 95% CI: -0.95 to 0.30; p = 0.30), visuospatial function (SMD = -1.12; 95% CI: -2.79 to 0.56; p = 0.19), attention (SMD = -0.94; 95% CI: -2.79to 0.91; p = 0.32), intelligence (SMD = -0.25; 95% CI: -0.73 to 0.22; p = 0.30), and self-reported cognitive status (SMD = -0.51; 95% CI: -1.38 to 0.35; p = 0.25) revealed parity between groups. Patients with ACoA treated endovascularly had superior memory and motor abilities. Other cognitive domains, including executive function, language, visuospatial function, attention, intelligence and self-reported cognitive status revealed no statistically significant differences between the two approaches. Trial Registration PROSPERO (International Prospective Register of Systematic Reviews) CRD42023461283; https://www.crd.york.ac.uk/prospero/display&#95;record.php?RecordID=461283., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Stereotactic radiosurgery (SRS) is an option for brain metastases (BM) not eligible for surgical resection, however, predictors of SRS outcomes are poorly known. The aim of this study is to investigate predictors of SRS outcome in patients with BM secondary to non-small cell lung cancer (NSCLC). The secondary objective is to analyze the value of volumetric criteria in identifying BM progression. This retrospective cohort study included patients >18 years of age with a single untreated BM secondary to NSCLC. Demographic, clinical, and radiological data were assessed. The primary outcome was treatment failure, defined as a BM volumetric increase 12 months after SRS. The unidimensional measurement of the BM at follow-up was also assessed. One hundred thirty-five patients were included, with a median BM volume at baseline of 1.1 cm 3 (IQR 0.4-2.3). Fifty-two (38.5%) patients had SRS failure at follow-up. Only right BM laterality was associated with SRS failure (p=0.039). Using the volumetric definition of SRS failure, the unidimensional criteria demonstrated a sensibility of 60.78% (46.11%-74.16%), specificity of 89.02% (80.18%-94.86%), positive LR of 5.54 (2.88-10.66) and negative LR of 0.44 (0.31-0.63). SRS demonstrated a 61.5% local control rate 12 months after treatment. Among the potential predictors of treatment outcome analyzed, only the right BM laterality had a significant association with SRS failure. The volumetric criteria were able to identify more subtle signs of BM increase than the unidimensional criteria, which may allow earlier diagnosis of disease progression and use of appropriate therapies., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: Temporary arterial occlusion (TAO) is a widespread practice in the surgical treatment of intracranial aneurysms. This study aimed to investigate TAO's role during ruptured aneurysm clipping as an independent prognostic factor on short- and long-term outcomes., Methods: This prospective cohort included 180 patients with ruptured intracranial aneurysms and an indication of microsurgical treatment. Patients who died in the first 12 hours after admission were excluded., Results: TAO was associated with intraoperative rupture (IOR) (odds ratio - OR = 10.54; 95% confidence interval - 95%CI 4.72-23.55; p < 0.001) and surgical complications (OR = 2.14; 95%CI 1.11-4.07; p = 0.01). The group with TAO and IOR had no significant difference in clinical (p = 0.06) and surgical (p = 0.94) complications compared to the group that had TAO, but no IOR. Among the 111 patients followed six months after treatment, IOR, number of occlusions, and total time of occlusion were not associated with Glasgow Outcome Scale (GOS) in the follow-up (respectively, p = 0.18, p = 0.30, and p = 0.73). Among patients who underwent TAO, IOR was also not associated with GOS in the follow-up (p = 0.29)., Conclusions: TAO was associated with IOR and surgical complications, being the latter independent of IOR occurrence. In long-term analysis, neither TAO nor IOR were associated with poor clinical outcomes.

Background: Critical closing pressure (CrCP) and resistance-area product (RAP) have been conceived as compasses to optimize cerebral perfusion pressure (CPP) and monitor cerebrovascular resistance, respectively. However, for patients with acute brain injury (ABI), the impact of intracranial pressure (ICP) variability on these variables is poorly understood. The present study evaluates the effects of a controlled ICP variation on CrCP and RAP among patients with ABI., Methods: Consecutive neurocritical patients with ICP monitoring were included along with transcranial Doppler and invasive arterial blood pressure monitoring. Internal jugular veins compression was performed for 60 s for the elevation of intracranial blood volume and ICP. Patients were separated in groups according to previous intracranial hypertension severity, with either no skull opening (Sk1), neurosurgical mass lesions evacuation, or decompressive craniectomy (DC) (patients with DC [Sk3])., Results: Among 98 included patients, the correlation between change (Δ) in ICP and the corresponding ΔCrCP was strong (group Sk1 r = 0.643 [p = 0.0007], group with neurosurgical mass lesions evacuation r = 0.732 [p < 0.0001], and group Sk3 r = 0.580 [p = 0.003], respectively). Patients from group Sk3 presented a significantly higher ΔRAP (p = 0.005); however, for this group, a higher response in mean arterial pressure (change in mean arterial pressure p = 0.034) was observed. Exclusively, group Sk1 disclosed reduction in ICP before internal jugular veins compression withholding., Conclusions: This study elucidates that CrCP reliably changes in accordance with ICP, being useful to indicate ideal CPP in neurocritical settings. In the early days after DC, cerebrovascular resistance seems to remain elevated, despite exacerbated arterial blood pressure responses in efforts to maintain CPP stable. Patients with ABI with no need of surgical procedures appear to remain with more effective ICP compensatory mechanisms when compared with those who underwent neurosurgical interventions., (© 2023. The Author(s).)

Glioblastoma (GBM) is the most common and aggressive glioma histological subtype, associated with high disability and poor survival. The etiology of this condition is still mostly unknown, and evidence about risk factors is elusive. The aim of this study is to identify modifiable risk factors for GBM. Electronic search was performed by two reviewers independently using the keywords and MeSH terms 'glioblastoma' OR 'glioma' OR 'brain tumor' AND 'risk factor'. The inclusion criteria were (1) observational studies or experimental studies on humans, (2) studies assessing the association between glioblastoma and exposure to modifiable conditions, and (3) studies published in English or Portuguese. Studies on the pediatric population or about exposure to ionizing radiation were excluded. A total of 12 studies were included. Seven were case-control studies, and five were cohort studies. The risk factors assessed included body mass index, alcohol consumption, exposure to magnetic fields, diabetes mellitus type 2 (DM2), and use of non-steroidal anti-inflammatory drugs (NSAID). No significant link was found between GBM incidence and DM2 or magnetic field exposure. On the other hand, higher BMI, alcohol consumption, and NSAID use demonstrated a protective effect on GMB risk. However, given the limited number of studies, it is not possible to obtain a behavioral recommendation; instead, these findings are relevant to guide future basic scientific studies on GBM oncogenesis., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Subarachnoid hemorrhage (SAH) prognosis remains poor. Vasospasm mechanism might be associated with inflammation. Neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) have been studied as inflammation markers and prognostic predictors., Objective: We aimed to investigate NLR and PLR in admission as predictors of angiographic vasospasm and functional outcome at 6 months., Methods: This cohort study included consecutive aneurysmal SAH patients admitted to a tertiary center. Complete blood count was recorded at admission before treatment. White blood cell count, neutrophil count, lymphocyte count, platelet count, NLR, and PLR were collected as independent variables. Vasospasm occurrence-modified Rankin scale (mRS), Glasgow outcome scale (GOS), and Hunt-Hess score at admission and at 6 months were recorded as dependent variables. Multivariable logistic regression models were used to adjust for potential confounding and to assess the independent prognostic value of NLR and PLR at admission., Results: A total of 74.1% of the patients were female, with mean age of 55.6 ± 12.4 years. At admission, the median Hunt-Hess score was 2 (interquartile range [IQR] 1), and the median mFisher was 3 (IQR 1). Microsurgical clipping was the treatment for 66.2% of the patients. Angiographic vasospasm incidence was 16.5%. At 6 months, the median GOS was 4 (IQR 0.75), and the median mRS was 3 (IQR 1.5). Twenty-one patients (15.1%) died. Neutrophil-to-lymphocyte ratio and PLR levels did not differ between favorable and unfavorable (mRS > 2 or GOS < 4) functional outcomes. No variables were significantly associated with angiographic vasospasm., Conclusion: Admission NLR and PLR presented no value for prediction of functional outcome or angiographic vasospasm risk. Further research is needed in this field., Competing Interests: The authors have no conflict of interest to declare., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution 4.0 International License, permitting copying and reproduction so long as the original work is given appropriate credit (https://creativecommons.org/licenses/by/4.0/).)

Analysis of intracranial pressure waveforms (ICPW) provides information on intracranial compliance. We aimed to assess the correlation between noninvasive ICPW (NICPW) and invasively measured intracranial pressure (ICP) and to assess the NICPW prognostic value in this population. In this cohort, acute brain-injured (ABI) patients were included within 5 days from admission in six Intensive Care Units. Mean ICP (mICP) values and the P2/P1 ratio derived from NICPW were analyzed and correlated with outcome, which was defined as: (a) early death (ED); survivors on spontaneous breathing (SB) or survivors on mechanical ventilation (MV) at 7 days from inclusion. Intracranial hypertension (IHT) was defined by ICP > 20 mmHg. A total of 72 patients were included (mean age 39, 68% TBI). mICP and P2/P1 values were significantly correlated (r = 0.49, p < 0.001). P2/P1 ratio was significantly higher in patients with IHT and had an area under the receiving operator curve (AUROC) to predict IHT of 0.88 (95% CI 0.78-0.98). mICP and P2/P1 ratio was also significantly higher for ED group (n = 10) than the other groups. The AUROC of P2/P1 to predict ED was 0.71 [95% CI 0.53-0.87], and the threshold P2/P1 > 1.2 showed a sensitivity of 60% [95% CI 31-83%] and a specificity of 69% [95% CI 57-79%]. Similar results were observed when decompressive craniectomy patients were excluded. In this study, P2/P1 derived from noninvasive ICPW assessment was well correlated with IHT. This information seems to be as associated with ABI patients outcomes as ICP.Trial registration: NCT03144219, Registered 01 May 2017 Retrospectively registered, https://www.clinicaltrials.gov/ct2/show/NCT03144219 ., (© 2022. The Author(s).)

Cerebral perfusion pressure (CPP) is normally expressed by the difference between mean arterial blood pressure (MAP) and intracranial pressure (ICP) but comparison of the separate contributions of MAP and ICP to human cerebral blood flow autoregulation has not been reported. In patients with acute brain injury (ABI), internal jugular vein compression (IJVC) was performed for 60 s. Dynamic cerebral autoregulation (dCA) was assessed in recordings of middle cerebral artery blood velocity (MCAv, transcranial Doppler), and invasive measurements of MAP and ICP. Patients were separated according to injury severity as having whole/undamaged skull, large fractures, or craniotomies, or following decompressive craniectomy. Glasgow coma score was not different for the three groups. IJVC induced changes in MCAv, MAP, ICP, and CPP in all three groups. The MCAv response to step changes in MAP and ICP expressed the dCA response to these two inputs and was quantified with the autoregulation index (ARI). In 85 patients, ARI was lower for the ICP input as compared with the MAP input (2.25 ± 2.46 vs. 3.39 ± 2.28; P < 0.0001), and particularly depressed in the decompressive craniectomy (DC) group ( n = 24, 0.35 ± 0.62 vs. 2.21 ± 1.96; P < 0.0005). In patients with ABI, the dCA response to changes in ICP is less efficient than corresponding responses to MAP changes. These results should be taken into consideration in studies aimed to optimize dCA by manipulation of CPP in neurocritical patients.

Objective: Torque Teno virus (TTV) is a recently discovered virus with high prevalence worldwide, that has been associated with vascular diseases. The aim of this study is to investigate the prevalence of TTV molecular DNA in the intracranial aneurysm (IA) artery walls., Method: Samples of IA walls were collected after microsurgical clipping from 35 patients with IA (22 ruptured/13 unruptured cases). The samples were submitted to molecular DNA extraction using the EasyMag automatized extractor and performed with Qiagen DNA extraction Minikit 250. The samples underwent PCR examination with primers for β-globin as internal control using the Nanodrop ® 2000 spectrophotometer. A quantitative (real-time) PCR with TTV-specific primers was performed. Clinical and radiological data of patients included was collected., Results: TTV was detected in 15 (42.85%) cases, being 10 (45.4%) ruptured and 5 (38.4%) unruptured ( p = 0.732) lesions. Multiple IAs accounted for 14 (40%) cases. Five cases (17.2%) had TTV+ and multiple aneurysms ( p = 0.73). Association between presence of virus and aneurysm rupture was not statistically significant ( p = 0.96)., Conclusion: This study demonstrated a relatively high prevalence of viral DNA in the walls of IAs. This is the first study to identify the presence of TTV DNA in IA's samples, which was found more often in ruptured lesions. This is an exploratory study, therefore, larger studies are required to clarify the relationships between inflammation, viral infection, IA formation and rupture., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Rabelo, Yoshikawa, Telles, Coelho, de Souza, de Oliveira, Mendoza, Braz-Silva, Boechat, Teixeira and Figueiredo.)

Aim: To evaluate the association between global cerebral edema (GCE) after subarachnoid hemorrhage (SAH) and its impact on functional outcome evaluated by the modified Rankin scale (mRS)., Material and Methods: This is a prospective cohort study with patients who were admitted to the hospital due to SAH. During the period from January 2018 to November 2019, 107 patients with intracranial aneurysms were enrolled. Using univariate and multivariate analysis, we sought to identify predictors and evaluated the impact of GCE on outcome after 6 months using the mRS., Results: GCE was present in 54 (50.5%) patients, of which 27 (25.2%) were mild, 20 (18.7%) moderate and 7 (6.5%) were severe. Univariate analysis identified high Hunt-Hess and Glasgow coma scale on clinical admission as predictors factors of GCE (p < 0.05), and higher modified Fisher scale as a radiological predictor of Glasgow coma scale (p < 0.05). Thirty-three (30.8%) patients were deceased at 6 months. Death or severe disability were predicted by higher age, poor clinical scale on admission and severe GCE (p < 0.05)., Conclusion: GCE on admission is independently associated with poor clinical outcomes at discharge, and six months after SAH. Given its strong association with poor clinical grade on admission, GCE should be considered a straightforward and radiological important marker of early brain injury, with ominous implications.

Purpose: To evaluate the risk factors for poor outcomes after surgical and endovascular treatment of aneurysmal subarachnoid hemorrhage (aSAH)., Methods: Patients with ≥ 18-years of age and aSAH were included, while patients who died within 12 h of admission or lost follow-up were excluded. All participants underwent standardized clinical and radiological assessment on admission and were reassessed at discharge and at 6-months follow-up using the Glasgow Outcome Scale (GOS)., Results: Death at discharge was associated with female gender, anterior communication artery (ACoA) aneurysm location and presence of atherosclerotic plaque in the surgical group, and with age in the endovascular group. Both groups had clinical condition on follow-up associated with mFisher score on admission and hypertension. GOS on follow-up was also associated with presence of atherosclerotic plaque and multiple aneurysms in surgical group, and with age in endovascular group., Conclusions: Subjects treated surgically are prone to unfavorable outcomes if atherosclerotic plaques and multiple aneurysms are present. In patients with endovascular treatment, age was the main predictor of clinical outcome.

Background: Temporary arterial occlusion (TAO) is a technique widely used in cerebrovascular surgery. However, few studies have evaluated the independent long-term effects of TAO or given detailed information about the complications during in-hospital stay., Objective: This study aims to investigate the independent impact of TAO during unruptured intracranial aneurysm surgery on short and long-term outcomes., Methods: The study included surgical elective patients diagnosed with unruptured aneurysm and indication of microsurgical treatment. Outcome assessment included occurrence of intra-operative (IOC) and post-operative (POC) complications, as well as Glasgow Outcome Scale (GOS) score 6 months after discharge., Results: 114 patients were included and 36 were followed. TAO was associated with POC (OR = 2.08; CI 95% 1.12-3.96; p = 0.01). The group with TAO and intraoperative rupture (IOR) did not differ from the group with TAO without IOR in terms of POC (p = 0.65) and IOC (p = 0.78). IOR (p = 0.16) and number of occlusions (p = 0.23) did not change GOS, but the total time of occlusion was associated with neurologic worsening (p = 0.034) during follow-up. The TAO group had larger aneurysm size and higher frequency of irregular lesions, when compared to the entire study group. Aneurysm location was not associated with POC (p = 0.25), IOC (0.17) or GOS (p = 0.75)., Conclusion: The location of temporary clip placement and the number of clips did not influence the short- and long-term outcomes of patients with unruptured intracranial aneurysms. However, presence of temporary clips was associated with POC regardless of IOR occurrence and increased total time of occlusion was associated with poor outcomes after 6 months., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Purpose: To analyze the role of serum creatinine levels as a biomarker of intracranial aneurysm outcomes., Methods: This is a prospective analysis of outcomes of patients with intracranial aneurysm. One hundred forty-seven patients with serum creatinine at admission and 6 months follow up were included. Linear and logistic regressions were used to analyze the data. Modified Rankin scale (mRS) was used to assess outcome., Results: Creatinine level was not directly related to aneurysm outcome nor aneurysm rupture (p > 0.05). However, patients with a glomerular filtration rate (GFR) lower than 72.50 mL·min-1 had an odds ratio (OR) of 3.049 (p = 0.006) for worse outcome. Similarly, aneurysm rupture had an OR of 2.957 (p = 0.014) for worse outcomes. Stepwise selection model selected 4 variables for outcomes prediction: serum creatinine, sex, hypertension and treatment. Hypertensive patients had, on average, an increase in 0.588 in mRS (p = 0.022), while treatment with microsurgery had a decrease in 0.555 (p = 0.038)., Conclusions: Patients with higher GFR had better outcomes after 6 months. Patients with higher GFR had better outcomes after 6 months. Creatinine presented an indirect role in GFR values and should be included in models for outcome prediction.

Objective: To identify current evidence on the use of topiramate for refractory status epilepticus., Methods: We reviewed the literature to investigate the efficacy of topiramate in the treatment of refractory status epilepticus. The search terms used were "status epilepticus", "refractory", "treatment" and "topiramate". No restrictions were used., Results: The search yielded 487 articles that reported using topiramate as a treatment for refractory status epilepticus and its outcomes. Case reports, review articles, and animal experiments were excluded. After excluding duplicates and applying inclusion and exclusion criteria, nine studies were included for analyses. Descriptive and qualitative analyses were performed, and the results were as follows: response rates (defined as termination in-hospital until 72 hours after the administration of topiramate) varied from 27% to 100%. The mortality rate varied from 5.9% to 68%. Positive functional long-term outcomes, defined as discharge, back to baseline or rehabilitation, were documented by seven studies, and the rates ranged between 4% and 55%. Most studies reported no or mild adverse effects., Conclusion: Topiramate was effective in terminating refractory status epilepticus, presented relatively low mortality and was well tolerated. Therefore, topiramate could be a good option as a third-line therapy for refractory status epilepticus, but further studies are necessary.

One of the first attempts to define brain death (BD) dates from 1963, and since then, the diagnosis criteria of that entity have evolved. In spite of the publication of practice parameters and evidence-based guidelines, BD is still causing concern and controversies in the society. The difficulties in determining brain death and making it understood by family members not only endorse futile therapies and increase health care costs, but also hinder the organ transplantation process. This review aims to give an overview about the definition of BD, causes, physiopathology, diagnosis criteria, and management of the potential brain-dead donor. It is important to note that the BD determination criteria detailed here follow the AAN's recommendations, but the standard practice for BD diagnosis varies from one country to another., (© 2021. Fondazione Società Italiana di Neurologia.)