CT perfusion extended window ischemic core estimation: Bayesian algorithm versus oscillation index singular value decomposition.

BACKGROUND AND PURPOSE: Ischemic core estimation by CT perfusion (CTp) is a diagnostic challenge, mainly because of the intrinsic noise associated with perfusion data. However, an accurate and reliable quantification of the ischemic core is critical in the selection of patients for reperfusion therapies. Our study aimed at assessing the diagnostic accuracy of two different CTp postprocessing algorithms, that is, the Bayesian Method and the oscillation index singular value decomposition (oSVD). METHODS: All the consecutive stroke patients studied in the extended time window (>4.5 hours from stroke onset) by CTp and diffusion-weighted imaging (DWI), between October 2019 and December 2021, were enrolled. The agreement between both algorithms and DWI was assessed by the Bland-Altman plot, Wilcoxon signed-rank test, Spearman's rank correlation coefficient, and the intraclass correlation coefficient (ICC). RESULTS: Twenty-four patients were enrolled (average age: 72 ± 15 years). The average National Institutes of Health Stroke Scale was 14.42 ± 6.75, the median Alberta Stroke Program Early CT score was 8.50 (interquartile range [IQR] = 7.75-9), and median time from stroke onset to neuroimaging was 7.5 hours (IQR = 6.5-8). There was an excellent correlation between DWI and oSVD (ρ = .87, p-value < .001) and DWI and Bayesian algorithm (ρ = .94, p-value < .001). There was a stronger ICC between DWI and Bayesian algorithm (.97, 95% confidence interval [CI]: .92-.99, p-value < .001) than between DWI and oSVD (.59, 95% CI: .26-.8, p-value < .001). DISCUSSION: The agreement between Bayesian algorithm and DWI was greater than between oSVD and DWI in the extended window. The more accurate estimation of the ischemic core offered by the Bayesian algorithm may well play a critical role in the accurate selection of patients for reperfusion therapies.

Different saccadic profile in bulbar versus spinal-onset amyotrophic lateral sclerosis.

Two clinical phenotypes characterize the onset of amyotrophic lateral sclerosis (ALS): the spinal variant, with symptoms beginning in the limbs, and the bulbar variant, affecting firstly speech and swallowing. The two variants show some distinct features in the histopathology, localization and prognosis, but to which extent they really differ clinically and pathologically remains to be clarified. Recent neuropathological and neuroimaging studies have suggested a broader spreading of the neurodegenerative process in ALS, extending beyond the motor areas, toward other cortical and deep grey matter regions, many of which are involved in visual processing and saccadic control. Indeed, a wide range of eye movement deficits have been reported in ALS, but they have never been used to distinguish the two ALS variants. Since quantifying eye movements is a very sensitive and specific method for the study of brain networks, we compared different saccadic and visual search behaviours across spinal ALS patients (n = 12), bulbar ALS patients (n = 6) and healthy control subjects (n = 13), along with cognitive and MRI measures, with the aim to define more accurately the two patients subgroups and possibly clarify a different underlying neural impairment. We found separate profiles of visually-guided saccades between spinal (short saccades) and bulbar (slow saccades) ALS, which could result from the pathologic involvement of different pathways. We suggest an early involvement of the parieto-collicular-cerebellar network in spinal ALS and the fronto-brainstem circuit in bulbar ALS. Overall, our data confirm the diagnostic value of the eye movements analysis in ALS and add new insight on the involved neural networks.

A "Post-mortem" of COVID-19-associated stroke: a case-control study.

OBJECTIVES: To assess whether COVID-19 could be a concurrent factor in the genesis and/or worsening of stroke and to provide data on COVID-19 -associated stroke patients during the first pandemic wave and comparative data on COVID-19 negative stroke patients in the same period. MATERIALS AND METHODS: This is a retrospective, observational, case-control, single centre study, carried out in a General Hospital in northern Italy. Sixty-three consecutive stroke patients were included, COVID-19-associated stroke was classified as cases and non COVID-19-associated stroke as controls. RESULTS: A total of 19/63 (28.8%) had a COVID-19-associated stroke, 11 /63 (17.5%) were haemorrhagic and 52/63 (82.5%) ischaemic. COVID-19-associated strokes were more severe (p-value 0.019) and had a higher risk of severe disability and/or death (OR 3.79, CI 95%: 1.21-11.93, p-value 0.19). The COVID-19-associated stroke patients with onset during hospitalization for COVID-19 had a more severe stroke than patients with COVID-19 onset during hospitalization for stroke (p-value 0.019). CONCLUSION: Although no relationship was observed between the stroke aetiology and COVID-19, intriguingly, COVID-associated stroke turned out to be more severe and disabling. Hopefully, further studies will provide more data and help in the management of this emerging population.

Multiple Sclerosis Treatment in the COVID-19 Era: A Risk-Benefit Approach.

The COVID-19 pandemic poses an ongoing global challenge, and several risk factors make people with multiple sclerosis (pwMS) particularly susceptible to running a severe disease course. Although the literature does report numerous articles on the risk factors for severe COVID-19 and vaccination response in pwMS, there is a scarcity of reviews integrating both these aspects into strategies aimed at minimizing risks. The aim of this review is to describe the risk of vulnerable pwMS exposed to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the issues related to the SARS-CoV-2 vaccine and to evidence possible future strategies in the clinical management of pwMS. The authors searched for papers on severe COVID-19 risk factors, SARS-CoV-2 vaccination and people with multiple sclerosis in support of this narrative literature review. We propose a multilevel strategy aimed at: the evaluation of risk factors for severe COVID-19 in people with multiple sclerosis, identifying the most appropriate vaccination schedule that is safe for people on disease-modifying drugs (DMDs) and a strict follow-up of high-risk people with multiple sclerosis to allow for the prompt administration of monoclonal antibodies to manage COVID-19 risks in this patient population.

Not all is COVID19: a case of eclampsia and posterior reversible encephalopathy syndrome in the emergency room.

In the so called COVID19 era, headache, fever and gastrointestinal symptoms are highly suggestive for SARS-CoV-2 infection, but in all the cases presenting to the emergency room, clinicians should always keep in mind alternative diagnoses, particularly if the patient is pregnant.  Life-threatening diseases, such as eclampsia and posterior reversible encephalopathy syndrome (PRES), should be promptly recognized and treated. Eclampsia is defined as a seizure occurring in association with pre-eclampsia, and it represents one of the major and serious obstetric disorders associated with significant maternal and perinatal morbidity and mortality. PRES is a distinctive clinical and imaging syndrome characterized by acute headaches, visual impairment, seizures, and altered sensorium, that can be associated with severe eclampsia. Emergency clinicians should always consider eclampsia in the differential diagnosis of headache in pregnant women. The prompt and accurate diagnosis of eclampsia/PRES is crucial to prevent adverse maternal and perinatal outcomes. Here we describe the case of a young pregnant woman admitted to our emergency department for fever, dyspnea, headache, nausea and vomiting, who developed generalized tonic clonic seizures and a subsequent status epilepticus due to eclampsia and PRES.

Diagnostic Accuracy of a Bedside Screening Tool for Dysphagia (BSTD) in Acute Stroke Patients.

BACKGROUND AND PURPOSE: an estimated 40-80% of acute ischemic stroke patients have dysphagia and about 14% develop stroke-associated pneumonia. However, it may be difficult to detect swallowing problems at admission. Moreover, there might not be an on-duty specialist skilled in the diagnosis of this condition. This study aimed at developing a user-friendly bedside examination to identify the risk of dysphagia in stroke patients at hospital admission. METHODS: a diagnostic accuracy study was carried out to assess the concurrent validity of a simple Bedside Screening Tool for Dysphagia (BSTD) in acute stroke. All the consecutive stroke patients admitted between January and April 2018 were enrolled. Sensitivity, specificity, positive (PPV), negative predictive values (NPV) and the Cohen K concordance index scores, reported by nurses and speech-pathologists, were assessed. RESULTS: a total of 67/120 patients (55.8%) were male; overall average age was 67.4 (range 45-91) and 80.8% of the whole population had a history of ischemic stroke. The nursing staff identified 33.3% of dysphagia cases at admission and the speech pathologists 30%. The Cohen K was 0.92 (optimal concordance when K was > 0.8), sensitivity was 100%, specificity 95.2%, PPV 90% and NPV 100%. CONCLUSIONS: our BSTD had a 100% negative predictive value, indicating that this screening test is very useful in ruling out/confirming dysphagia in acute stroke patients.

Lactate dehydrogenase and C-reactive protein as predictors of respiratory failure in CoVID-19 patients.

OBJECTIVE: The dramatic worldwide CoVID-19 infection requires the identification of a reliable and inexpensive tool to quickly discriminate patients with a more unfavorable outcome. METHODS: We performed routine laboratory tests suitable to identify tissue damage and inflammatory status in 123 consecutive CoVID-19 patients admitted to the Emergency Department of the hospital of Piacenza (Emilia-Romagna, Northern Italy). The results were correlated with patients' respiratory function evaluated by the partial pressure of arterial oxygen to fraction of inspired oxygen ratio (PaO2/FiO2). RESULTS: The most common laboratory abnormalities were lymphocytopenia and elevated values of C-reactive protein (CRP) and lactate dehydrogenase (LDH). Aspartate aminotransferase (AST), alanine aminotransferase (ALT) and creatine kinase (CK) were also increased. The respiratory performance (PaO2/FiO2) showed a strong inverse correlation with LDH (r = 0.62, r2 0.38, p value < 0.0001) and CRP (r = 0.55, r2 0.31, p value < 0.0001). PaO2/FiO2 values also showed a significant inverse correlation with age (r = -0.37, p < 0.0001), AST (r = -0.31, p < 0.01), WBC (r = -0.49, p < 0.0001), neutrophils count (r = -0.5, p < 0.001). ROC curves showed a sensitivity of 75% and specificity of 70% for the LDH cut-off value of 450 U/L and a sensitivity of 72% and specificity of 71% for the CRP cut-off value of 11 mg/dl in identifying CoVID-19 with moderate-severe ARDS. CONCLUSIONS: LDH and CRP may be related to respiratory function (PaO2/FiO2) and be a predictor of respiratory failure in CoVID-19 patients. LDH and CRP should be considered a useful test for the early identification of patients who require closer respiratory monitoring and more aggressive supportive therapies to avoid poor prognosis.

The cerebellum improves the precision of antisaccades by a latency-duration trade-off.

The cerebellum adapts motor responses by controlling the gain of a movement, preserving its accuracy and by learning from endpoint errors. Adaptive behavior likely acts not only in the motor but also in the sensory, behavioral, and cognitive domains, thus supporting a role of cerebellum in monitoring complex brain performances. Here, we analyzed the relationship between saccade latency, duration and endpoint error of antisaccades in a group of 10 idiopathic cerebellar atrophy (ICA) patients compared to controls. The latency distribution was decomposed in a decision time and a residual time. Both groups showed a trade-off between duration and decision time, with a peak of entropy within the range of this trade-off where the information flow was maximized. In cerebellar patients, greater reductions of duration as the time of decision increased, were associated with a lower probability for a saccade to fall near the target, with a constant low entropy outside the optimal time window. We suggest a modulation of saccade duration, depending on the latency-related decision time (accumulation of sensory and motor evidences in favor of a goal-directed movement), normally adopted to perform efficient trajectories in goal-directed saccades. This process is impaired in cerebellar patients suggesting a role for the cerebellum in monitoring voluntary motor performance by controlling the movement onset until the ambiguity of planning is resolved.