Acute telestroke evaluations during the COVID-19 pandemic.

We sought to analyze the effect of COVID-19 on telestroke requests and to characterize patients remotely evaluated for acute ischemic stroke (AIS) during this time. This study is a retrospective database review of all telestroke requests at one academic vascular neurology center telestroke network with seven remote sites in the USA between March 15 and April 30, 2020. Data were compared with historical cohort spanning same time frame in 2019 using parametric or nonparametric methods as appropriate. Among telestroke requests, characteristics of age, gender, race/ethnicity, National Institutes of Health Stroke Scale (NIHSS), primary diagnosis of AIS or transient ischemic attack (TIA), and number of patients receiving intravenous alteplase (IV-rtPA) and endovascular therapy (ET) were recorded. There was a 53% decrease in telestroke evaluation requests in 2020 from 2019 (p < 0.00001). Mean NIHSS in 2020 was 9.1 (SD ± 8.4) and mean NIHSS in 2019 was 7.2 (SD ± 7.3) (p = 0.122). Among patients with primary diagnosis of suspected AIS or TIA, mean age was 60.5 years in 2020 (SD ± 17.5) and mean age of 67.0 years in 2019 (SD ± 16.0) (p = 0.038). A significant lower number of telestroke evaluations were performed with a higher mean NIHSS overall and a lower mean age among AIS/TIA-suspected patients. Higher NIHSS and severity in all telestroke evaluations reflect neurological manifestations of AIS and mimics, possibly influenced by COVID-19. The younger age of those with suspected AIS or TIA reflects thrombotic complications in atypical stroke populations.

The Influence of Diffusion Weighted Imaging Lesions on Outcomes in Patients with Acute Spontaneous Intracerebral Hemorrhage.

BACKGROUND/OBJECTIVE: Diffusion weighted imaging (DWI) lesions have been well described in patients with acute spontaneous intracerebral hemorrhage (sICH). However, there are limited data on the influence of these lesions on sICH functional outcomes. We conducted a prospective observational cohort study with blinded imaging and outcomes assessment to determine the influence of DWI lesions on long-term outcomes in patients with acute sICH. We hypothesized that DWI lesions are associated with worse modified Rankin Scale (mRS) at 3 months after hospital discharge. METHODS: Consecutive sICH patients meeting study criteria were consented for an magnetic resonance imaging (MRI) scan of the brain and evaluated for remote DWI lesions by neuroradiologists blinded to the patients' hospital course. Blinded mRS outcomes were obtained at 3 months. Logistic regression was used to determine significant factors (p < 0.05) associated with worse functional outcomes defined as an mRS of 4-6. The generalized estimating equation (GEE) approach was used to investigate the effect of DWI lesions on dichotomized mRS (0-3 vs 4-6) longitudinally. RESULTS: DWI lesions were found in 60 of 121 patients (49.6%). The presence of a DWI lesion was associated with increased odds for an mRS of 4-6 at 3 months (OR 5.987, 95% CI 1.409-25.435, p = 0.015) in logistic regression. Using the GEE model, patients with a DWI lesion were less likely to recover over time between 14 days/discharge and 3 months (p = 0.005). CONCLUSIONS: DWI lesions are common in primary sICH, occurring in almost half of our cohort. Our data suggest that DWI lesions are associated with worse mRS at 3 months in good grade sICH and are predictive of impaired recovery after hospital discharge. Further research into the pathophysiologic mechanisms underlying DWI lesions may lead to novel treatment options that may improve outcomes associated with this devastating disease.

Muscular effort differentially mediates perception of heaviness and length via dynamic touch.

Our ability to perceive properties of handheld objects (e.g., heaviness, orientation, length, width, and shape) by wielding via dynamic touch is crucial for tooling and other forms of object manipulation-activities that are the basis of much human experience. Here, we investigated how muscular effort mediates perception of heaviness and length via dynamic touch. Twelve participants wielded nine occluded elongated objects of distinct moments of inertia and reported their perceptual judgments of heaviness and length. We measured the electromyography (EMG) activity of the participants' biceps brachii, flexor carpi radialis, and flexor carpi ulnaris muscles during wielding. Distinct single-valued functions of the eigenvalues I1 and I3 of the inertial tensor, I, closely predicted perceived heaviness and perceived length of the wielded objects. Perceived heaviness showed a direct and linear relationship with EMG activity of biceps brachii, flexor carpi radialis, and flexor carpi ulnaris. However, while perceived length showed a very weak relationship with EMG activity of biceps brachii, we found no association between perceived length and EMG activity of flexor carpi radialis and flexor carpi ulnaris. Our findings indicate that muscular effort contributes directly to perception of heaviness, but likely only serves as a medium for perception of length. While the same physical variable-i.e., the moment of inertia-provides the informational support for perception of heaviness and length, distinct psychophysiological processes underlie perception of heaviness and length via dynamic touch.

Fractal fluctuations in muscular activity contribute to judgments of length but not heaviness via dynamic touch.

The applied muscular effort to wield, hold, or balance an object shapes the medium by which action-relevant perceptual judgments (e.g., heaviness, length, width, and shape) are derived. Strikingly, the integrity of these judgments is retained over a range of exploratory conditions, a phenomenon known as perceptual invariance. For instance, judgments of length do not vary with the speed of rotation, despite the greater muscular effort required to wield objects at higher speeds. If not the amount of muscular effort alone, then what features of the neuromuscular activity implicated while wielding objects contribute to perception via dynamic touch? In the present study, we investigated how muscular activity mediates perception of heaviness and length of objects via dynamic touch. We measured EMG activity in biceps brachii and flexor carpi radialis as participants wielded objects of different moments of inertia. We found that variation in the amount of muscular effort (literally, root-mean-square values of EMG activity) predicted variations in judgments of heaviness but not length. In contrast, fluctuations in the activity of biceps brachii and flexor carpi radialis were fractal, and variation in the degree of fractality in the two muscles predicted variation in judgments of length. These findings reflect the distinct implications of dynamic touch for perception of heaviness and length. Perceptions of length can be derived from minimal effort, and muscular effort only shapes the medium from which judgments of length are derived. We discuss our findings in the context of the body as a multifractal tensegrity system, wherein perceptual judgments of length by wielding implicate, at least in part, rapidly diffusing mechanotransduction perturbations cascading across the whole body.

The Spectrum of Nontraumatic Convexity Subarachnoid Hemorrhage.

BACKGROUND: Nontraumatic convexity subarachnoid hemorrhage (cSAH) is a nonaneurysmal variant that is associated with diverse etiologies. METHODS: With IRB approval, we retrospectively reviewed consecutive nontraumatic cSAH from July 1, 2006 to July 1, 2016. Data were abstracted on demographics, medical history, neuroimaging, etiology, and clinical presentation. RESULTS: We identified 94 cases of cSAH. The cases were classified according to the following etiologies: reversible cerebral vasoconstriction syndrome (RCVS) 17 (18%), cerebral amyloid angiopathy (CAA) 15 (16%), posterior reversible encephalopathy syndrome 16 (17%), cerebral venous thrombosis 10 (11%), large artery occlusion 7 (7%), endocarditis 6 (6%), and cryptogenic 25 (27%). Early rebleeding occurred in 9 (10%) patients. Time from initial imaging to CT rebleeding was 40 hours (range, 5-74). CAA was associated with the highest mean age at 75.8 and RCVS the lowest at 47.6 years (P< .0001). Among patients with RCVS, initial vascular imaging was negative in 6 (35%), and repeat imaging documented vasoconstriction at a mean delay of 5 days (range, 3-16). CONCLUSION: There were significant differences among the subgroups in cSAH, with CAA presenting as older men with transient neurological deficits, and RCVS presenting as younger women with thunderclap headache. Rebleeding was seen in 10% of cSAH patients. One-third of RCVS patients with cSAH required repeat vascular imaging to diagnose vasoconstriction.

Location of a grasped object's effector influences perception of the length of that object via dynamic touch.

Perception of properties of a grasped object via dynamic touch (wielding) contributes to dexterity in tool use (e.g., using a hammer, screwdriver) and sports (e.g., hockey, tennis). These activities differ from simple object manipulation in that they involve making contact with an intended target. In the present study, we examined whether and how making (percussive) contact with a target influences perception of the length of a grasped object via dynamic touch. Making contact with a target by the tip resulted in a more accurate perception of the length than simple wielding. However, making contact with the target at a point along the length did not influence the accuracy of perception. These findings suggest that the location of a grasped object's effector influences perception of properties of that object via dynamic touch. We discuss these findings in terms of time-varying properties of vibrations generated by the percussive contact of the grasped object and target.

Participation in a Tele-Stroke Program Improves Timeliness of Intravenous Thrombolysis Delivery.

BACKGROUND: We sought to assess the effects of participation in a tele-stroke program on timeliness of intravenous tissue plasminogen activator (IVtPA) administration. METHODS: Among 259 consecutive acute ischemic stroke patients treated with IVtPA through the Rush tele-stroke program, we compared two cohorts: Period 1 (July 2011 to June 2013) and Period 2 (July 2013 to July 2014). We collected data on demographics, National Institutes of Health Stroke Scale (NIHSS), and times of last known normal (LKN), initiation of tele-stroke consult, and IVtPA administration. RESULTS: The mean age was 69.6 years, 56% were female, the mean NIHSS was 11.8, and 41.7% patients were transferred to the hub site. The mean time from initiation of tele-stroke consult to IVtPA administration was 42.2 min. Time from initiation of tele-stroke consult to IVtPA administration improved from Period 1 to Period 2 (49.9 min vs. 35 min, p < 0.0001). This improvement was due to faster mean time from initiation of tele-stroke consult to IVtPA advised (17.4 min vs. 12.5 min, p < 0.0001) and faster mean time from IVtPA advised to administration (33.1 min vs. 22.5 min, p < 0.0001). The mean time from LKN to IVtPA given was also significantly improved (148.6 min vs. 160.9 min, p 0.045). CONCLUSIONS: Participation in a tele-stroke program associated with improvement in the timeliness of IVtPA delivery.

Three-Month Outcomes Are Poor in Stroke Patients with Cancer Despite Acute Stroke Treatment.

INTRODUCTION: Stroke risk is increased in cancer patients. Prognosis in these patients is poor, with higher in-hospital mortality and increased subsequent mortality. However, data on stroke in cancer patients are limited, specifically regarding acute stroke treatment and functional outcomes. We aim to determine the functional outcomes of cancer patients admitted with acute stroke. MATERIALS AND METHODS: We retrospectively reviewed patients carrying a diagnosis of cancer who were admitted with acute ischemic stroke between March 2013 and February 2016. Demographics, cerebrovascular risk factors, stroke characteristics including acute treatment, and characteristics of their cancer history and treatment were abstracted. The primary outcome measures included in-hospital mortality and 3-month functional outcome (as assessed by the modified Rankin Scale [mRS] score, with mRS scores of 3-6 considered poor functional outcome). Further outcome measures included length of stay and discharge destination. FINDINGS: Forty-nine patients met the inclusion criteria, with a median admission National Institutes of Health Stroke Scale score of 8. Twelve patients (24.4%) underwent acute stroke treatment. The most common stroke etiology was hypercoagulability of malignancy (21, 42.9%). The three-month mortality was 46.9%; half of survivors had poor functional outcome. Functional outcomes did not differ by cancer type, stage, or year since diagnosis; on multivariate analysis only high admission NIHSS score was associated with poor functional outcome (P = .002). CONCLUSION: Nearly half of patients with cancer and stroke die within 3 months, and functional outcome is poor for 50% of 3-month survivors despite consideration of acute stroke treatment. Future research should address the role of hypercoagulability in the outcome prediction of stroke patients with cancer.

MRI Detection of Cerebral Infarction in Subarachnoid Hemorrhage.

OBJECTIVE: To investigate magnetic resonance imaging (MRI) detection of cerebral infarction (CI) in patients presenting with subarachnoid hemorrhage (SAH). BACKGROUND: CI is a well-known complication of SAH that is typically detected on computed tomography (CT). MRI has improved sensitivity for acute CI over CT, particularly with multiple, small, or asymptomatic lesions. METHODS: With IRB approval, 400 consecutive SAH patients admitted to our institution from August 2006 to March 2011 were retrospectively reviewed. Traumatic SAH and secondary SAH were excluded. Data were collected on demographics, cause of SAH, Hunt Hess and World Federation of Neurosurgical Societies grades, and neuroimaging results. MRIs were categorized by CI pattern as single cortical (SC), single deep (SD), multiple cortical (MC), multiple deep (MD), and multiple cortical and deep (MCD). RESULTS: Among 123 (30.8 %) SAH patients who underwent MRIs during their hospitalization, 64 (52 %) demonstrated acute CI. The mean time from hospital admission to MRI was 5.7 days (range 0-29 days). Among the 64 patients with MRI infarcts, MRI CI pattern was as follows: MC in 20 (31 %), MCD in 18 (28 %), SC in 16 (25 %), SD in 3 (5 %), MD in 2 (3 %), and 5 (8 %) did not have images available for review. Most infarcts detected on MRI (39/64 or 61 %) were not visible on CT. CONCLUSIONS: The use of MRI increases the detection of CI in SAH. Unlike CT studies, MRI-detected CI in SAH tends to involve multiple vascular territories. Studies that rely on CT may underestimate the burden of CI after SAH.

Risk stratification for the in-hospital mortality in subarachnoid hemorrhage: the HAIR score.

BACKGROUND: The intracerebral hemorrhage (ICH) score is a simple grading scale that can be used to stratify risk of 30 day mortality in ICH patients. A similar risk stratification scale for subarachnoid hemorrhage (SAH) is lacking. We sought to develop a risk stratification mortality score for SAH. METHODS: With approval from the Institutional Review Board, we retrospectively reviewed 400 consecutive SAH patients admitted to our institution from August 1, 2006 to March 1, 2011. The SAH score was developed from a multivariable logistic regression model which was validated with bootstrap method. A separate cohort of 302 SAH patients was used for evaluation of the score. RESULTS: Among 400 patients with SAH, the mean age was 56.9 ± 13.9 years (range, 21.5-96.2). Among the 366 patients with known causes of SAH, 292 (79.8%) of patients had aneurysmal SAH, 65 (17.8%) were angiogram negative, and 9 (2%) were other vascular causes. The overall in-hospital mortality rate was 20%. In multivariable analysis, the variables independently associated with the in-hospital mortality were Hunt and Hess score (HH) (p < 0.0001), age (p < 0.0001), intraventricular hemorrhage (IVH) (p = 0.049), and re-bleed (p = 0.01). The SAH score (0-8) was made by adding the following points: HH (HH1-3 = 0, HH4 = 1, HH5 = 4), age (<60 = 0, 60-80 = 1, ≥80 = 2), IVH (no = 0, yes = 1), and re-bleed within 24 h (no = 0, yes = 1). Using our model, the in-hospital mortality rates for patients with score of 0, 1, 2, 3, 4, 5, 6, and 7 were 0.9, 4.5, 9.1, 34.5, 52.9, 60, 82.1, and 83.3% respectively. Validation analysis indicates good predictive performance of this model. CONCLUSION: The SAH score allows a practical method of risk stratification of the in-hospital mortality. The in-hospital mortality increases with increasing SAH mortality score. Further investigation is warranted to validate these findings.