Global uncertainty in the diagnosis of neurological complications of SARS-CoV-2 infection by both neurologists and non-neurologists: An international inter-observer variability study.

INTRODUCTION: Uniform case definitions are required to ensure harmonised reporting of neurological syndromes associated with SARS-CoV-2. Moreover, it is unclear how clinicians perceive the relative importance of SARS-CoV-2 in neurological syndromes, which risks under- or over-reporting. METHODS: We invited clinicians through global networks, including the World Federation of Neurology, to assess ten anonymised vignettes of SARS-CoV-2 neurological syndromes. Using standardised case definitions, clinicians assigned a diagnosis and ranked association with SARS-CoV-2. We compared diagnostic accuracy and assigned association ranks between different settings and specialties and calculated inter-rater agreement for case definitions as "poor" (κ ≤ 0.4), "moderate" or "good" (κ > 0.6). RESULTS: 1265 diagnoses were assigned by 146 participants from 45 countries on six continents. The highest correct proportion were cerebral venous sinus thrombosis (CVST, 95.8%), Guillain-Barré syndrome (GBS, 92.4%) and headache (91.6%) and the lowest encephalitis (72.8%), psychosis (53.8%) and encephalopathy (43.2%). Diagnostic accuracy was similar between neurologists and non-neurologists (median score 8 vs. 7/10, p = 0.1). Good inter-rater agreement was observed for five diagnoses: cranial neuropathy, headache, myelitis, CVST, and GBS and poor agreement for encephalopathy. In 13% of vignettes, clinicians incorrectly assigned lowest association ranks, regardless of setting and specialty. CONCLUSION: The case definitions can help with reporting of neurological complications of SARS-CoV-2, also in settings with few neurologists. However, encephalopathy, encephalitis, and psychosis were often misdiagnosed, and clinicians underestimated the association with SARS-CoV-2. Future work should refine the case definitions and provide training if global reporting of neurological syndromes associated with SARS-CoV-2 is to be robust.

Acute Cytotoxic and Vasogenic Edema after Subarachnoid Hemorrhage: A Quantitative MRI Study.

BACKGROUND AND PURPOSE: The mechanism of early brain injury following subarachnoid hemorrhage is not well understood. We aimed to evaluate if cytotoxic and vasogenic edema are contributing factors. MATERIALS AND METHODS: A retrospective analysis was conducted in patients with SAH undergoing diffusion-weighted MR imaging within 72 hours of onset. Apparent diffusion coefficient values derived from DWI were evaluated by using whole-brain histograms and 19 prespecified ROIs in patients with SAH and controls with normal findings on MRI. Cytotoxic edema observed outside the ROIs was assessed in patients with SAH. The average median ADC values were compared between patients with SAH and controls and patients with SAH with mild (Hunt and Hess 1-3) versus severe early brain injury (Hunt and Hess 4-5). RESULTS: We enrolled 33 patients with SAH and 66 controls. The overall average median whole-brain ADC was greater for patients with SAH (808 × 10-6 mm2/s) compared with controls (788 × 10-6 mm2/s, P < .001) and was higher in patients with SAH across ROIs after adjusting for age: cerebral gray matter (826 versus 803 × 10-6 mm2/s, P = .059), cerebral white matter (793 versus 758 × 10-6 mm2/s, P = .023), white matter tracts (797 versus 739 × 10-6 mm2/s, P < .001), and deep gray matter (754 versus 713 × 10-6 mm2/s, P = .016). ADC values trended higher in patients with Hunt and Hess 4-5 versus those with Hunt and Hess 1-3. Early cytotoxic edema was observed in 13 (39%) patients with SAH and was more prevalent in those with severe early brain injury (87.5% of patients with Hunt and Hess 4-5 versus 24.0% of those with Hunt and Hess 1-3, P = .001). CONCLUSIONS: Age-adjusted ADC values were globally increased in patients with SAH compared with controls, even in normal-appearing brain regions, suggesting diffuse vasogenic edema. Cytotoxic edema was also present in patients with SAH and correlated with more severe early brain injury.

Neurologic complications of acute environmental injuries.

Environmental injuries can result in serious neurologic morbidity. This chapter reviews neurologic complications of thermal burns, smoke inhalation, lightning strikes, electric injury, near drowning, decompression illness, as well as heat stroke and accidental hypothermia. Knowing the pathophysiology and clinical presentation of such injuries is essential to proper management of primary and secondary medical complications. This chapter highlights the most frequently encountered neurologic injuries secondary to common environmental hazards, divided into the topics: injuries related to fire, electricity, water, and the extremes of temperature.

Degree of Collaterals and Not Time Is the Determining Factor of Core Infarct Volume within 6 Hours of Stroke Onset.

BACKGROUND AND PURPOSE: Growth of the core infarct during the first hours of ischemia onset is not well-understood. We hypothesized that factors other than time from onset of ischemia contribute to core infarct volume as measured by MR imaging. MATERIALS AND METHODS: Prospectively collected clinical and imaging data of consecutive patients with stroke presenting between March 2008 and April 2013 with anterior circulation large-vessel occlusion and MR imaging performed within 6 hours from the time of onset were reviewed. The association of time from onset, clinical, and radiographic features with DWI volume was assessed by using χ(2) and Mann-Whitney U tests. RESULTS: Of 91 patients, 21 (23%) underwent MR imaging within 0-3 hours from onset, and 70 (76%), within 3-6 hours. Median MR imaging infarct volume was similar in both timeframes, (24.7 versus 29.4 mL, P = .906), and there was no difference in the proportion of patients with large infarct volumes (≥70 mL, 23.8% versus 22.8%, P = .928). Using receiver operating characteristic analysis, we detected no association between the time from onset and MR imaging infarct volume (area under the curve = 0.509). In multivariate analysis, CTA collaterals (>50% of the territory) (adjusted OR, 0.192; 95% CI, 0.04-0.9; P = .046), CTA ASPECTS (adjusted OR, 0.464; 95% CI, 0.3-0.8; P = .003), and a history of hyperlipidemia (adjusted OR, 11.0; 95% CI, 1.4-88.0; P = .023) (but not time from stroke onset to imaging) were independent predictors of MR imaging infarct volume. CONCLUSIONS: Collateral status but not time from stroke onset to imaging was a predictor of the size of core infarct in patients with anterior circulation large-vessel occlusion presenting within 6 hours from onset.

Seizures after Onyx embolization for the treatment of cerebral arteriovenous malformation.

Onyx embolization of cerebral arteriovenous malformations (AVM) has become increasingly common. We explored the risk of seizures after Onyx use.A retrospective review was conducted of 20 patients with supratentorial brain arteriovenous malformation (AVM) who received Onyx embolization between 2006 and 2009. Baseline demographics, clinical history, seizure history, AVM characteristics and treatment were compared between those who developed post-onyx seizure and those who did not. MRIs were reviewed for edema following Onyx treatment.Of 20 patients who underwent Onyx embolization, the initial AVM presentation was hemorrhage in 40% (N=8). The median number of embolizations was two (range 1-4) and the median final obliteration amount was 90% (range 50-100%). A history of seizure was present in 50% (N=10) of patients pre-embolization and 12 (60%) patients received seizure medications (treatment or prophylaxis) prior to embolization. Seizur post-Onyx embolization occurred in 45% (N=9). The median time to seizur post-Onyx was seven days (range 0.3-210). Four patients (20%) with seizures post-Onyx had no seizure history. Two of these patients (10%) had no other identifiable cause for seizure other than recent Onyx embolization. Seizures in these two patients occurred within 24 hours of Onyx administration. Among patients with post-Onyx seizures, there was a trend toward larger AVM size (P=0.091) and lower percent obliteration (P=0.062). Peri-AVM edema was present in 75% of MRIs performed within one month of Onyx treatment and may represent a possible etiology for seizures.New onset seizures post-Onyx embolization are not uncommon. Further study of seizure prevention is warranted.

Electrographic seizures and periodic discharges after intracerebral hemorrhage.

OBJECTIVE: To determine the frequency and significance of electrographic seizures and other EEG findings in patients with intracerebral hemorrhage (ICH). METHODS: We reviewed 102 consecutive patients with ICH who underwent continuous electroencephalographic monitoring (cEEG). Demographic, clinical, radiographic, and cEEG findings were recorded. Using multivariate logistic regression analysis, we determined factors associated with 1) electrographic seizures, 2) periodic epileptiform discharges (PEDs), and 3) poor outcome (death, vegetative or minimally conscious state) at hospital discharge. RESULTS: Seizures occurred in 31% (n = 32) of patients with ICH, prior to cEEG in 19 patients. Eighteen percent (n = 18) of patients had electrographic seizures; only one of these patients also had clinical seizures while on cEEG. After controlling for demographic and clinical predictors, only an increase in ICH volume of 30% or more between admission and 24-hour follow-up CT scan was associated with electrographic seizures (33% vs 15%; OR 9.5, 95% CI 1.7 to 53.8). PEDs were less frequently seen in those with hemorrhages located at least 1 mm from the cortex (8% vs 29%; OR 0.2, 95% CI 0.1 to 0.7). PEDs were independently associated with poor outcome (65% vs 17%; OR 7.6, 95% CI 2.1 to 27.3). In patients with electrographic seizures, the first seizure was detected within the first hour of cEEG monitoring in 56% and within 48 hours in 94%. CONCLUSIONS: Seizures occurred in one third of patients with intracerebral hemorrhage (ICH) and over half were purely electrographic. Electrographic seizures were associated with expanding hemorrhages, and periodic discharges with cortical ICH and poor outcome. Further research is needed to determine if treating or preventing seizures or PEDs might lead to improved outcome after ICH.

Cerebrovascular reactivity and vasospasm after subarachnoid hemorrhage: a pilot study.

The authors performed serial transcranial Doppler (TCD) and carbon dioxide reactivity (CO2R) testing in 20 aneurysmal subarachnoid hemorrhage patients to determine whether impaired cerebrovascular reactivity was associated with symptomatic vasospasm. Symptomatic vasospasm occurred in 9 of 14 patients with abnormal CO2R and in none of 6 patients with preserved reactivity (p = 0.011). Abnormal CO2R preceded the onset of vasospasm in 7 of 9 patients. Abnormal standard TCD testing was not associated with vasospasm.

Right-side endocarditis in injection drug users: review of proposed mechanisms of pathogenesis.

Infective endocarditis of the right-side heart valves occurs commonly in injection drug users. Although a variety of hypotheses have been put forward to explain this clinical observation, no single hypothesis is adequate. In this article, basic scientific, clinical, and microbiological data on this topic are presented. It is apparent that no clear unifying mechanism emerges to explain the well-documented clinical predilection for the infection of the right-side heart valves in this population. Further investigation of this topic utilizing large international clinical registries may help to clarify matters further.