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BackgroundEarly endovascular intervention team mobilization may reduce reperfusion times and improve clinical outcomes for patients with acute ischemic stroke (AIS) with a possible intervenable vessel occlusion (IVO). In an emergency department or mobile stroke unit, incorporating rapidly available non-contrast CT (NCCT) information with examination findings may improve the accuracy of arterial occlusion prediction scales. For this purpose, we developed a rapid and straightforward IVO predictive instrument—the T3AM2PA1scale.MethodsThe T3AM2PA1scale was retrospectively derived from our ‘Get with the Guidelines’ database. We included all patients with acute stroke alert between January 2017 and August 2018 with a National Institutes of Health Stroke Scale (NIHSS) score between 5 and 25 inclusive. Different pre-intervention variables were collected, including itemized NIHSS and NCCT information. The T3AM2PA1scale was also compared with other commonly used scales and was validated in a separate sequential retrospective cohort of patients with a full range of NIHSS scores.Results574 eligible patients from 2115 acute stroke alerts were identified. The scale was established with five items (CT hyperdense sign, parenchymal hypodensity, lateralizing hemiparesis, gaze deviation, and language disturbance), with a total score of 9. To minimize unnecessary angiography, a cut-off of ≥5 for IVO detection yielded a sensitivity of 52%, a specificity of 90%, and a positive predictive value of 76%.ConclusionsThe T3AM2PA1scale accurately predicts the presence of clinical IVO in patients with AIS. Adopting the T3AM2PA1scale could reduce revascularization times, improve treatment outcomes, and potentially reduce disability.

BackgroundDiffuse correlation spectroscopy (DCS) is a non-invasive optical technique that enables continuous blood flow measurements in various organs, including the brain. DCS quantitatively measures blood flow from temporal fluctuations in the intensity of diffusely reflected light caused by the dynamic scattering of light from moving red blood cells within the tissue.MethodsWe performed bilateral cerebral blood flow (CBF) measurements using a custom DCS device in patients undergoing neuroendovascular interventions for acute ischemic stroke. Experimental, clinical, and imaging data were collected in a prospective manner.ResultsThe device was successfully applied in nine subjects. There were no safety concerns or interference with the standard angiography suite or intensive care unit workflow. Six cases were selected for final analysis and interpretation. DCS measurements with photon count rates greater than 30 KHz had sufficient signal-to-noise to resolve blood flow pulsatility. We found an association between angiographic changes in cerebral reperfusion (partial or complete reperfusion established in stroke thrombectomy cases; temporary flow arrest during carotid artery stenting) and those observed intraprocedurally with CBF measurements via DCS. Limitations of the current technology included sensitivity to the interrogated tissue volume under the probe and the effect of local changes in tissue optical properties on the accuracy of CBF estimates.ConclusionOur initial experience with DCS in neurointerventional procedures showed the feasibility of this non-invasive approach in providing continuous measurement of regional CBF brain tissue properties.

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To report and associate acute cerebral infarctions in 2 young, previously healthy siblings with use of the street drug known as “spice” (a synthetic marijuana product, also known as “K2”), which they independently smoked before experiencing acute embolic-appearing ischemic strokes.

For decades, neurologists have been advocating that anyone with acute focal deficits report immediately to the closest hospital’s emergency room. Major advancements in the hyperacute diagnosis and treatment of stroke have justified our call-to-action slogan of “Time is Brain”—faster therapy leads to superior outcomes. However, this mantra has been recently usurped by the catchphrase “Stay at Home” during the coronavirus disease 2019 (COVID-19) pandemic. Fewer patients are presenting to hospitals with acute stroke; our census is down. Presumably the etiology of this phenomenon is either strict “social distancing” that some people may misperceive to exclude even emergent situations, or fears of contracting the virus while hospitalized. In this Short Report, we describe the year-over-year drop in stroke volume (ischemic and hemorrhagic both) coinciding with a paradoxical rise in acute reperfusion therapies at our university hospital. These data imply that stroke patients with mild/moderate symptoms are most likely staying home, and not receiving urgent therapies, and correspondingly, only the most severely disabled stroke patients are ultimately seeking and receiving help. We must remind our patients and the general public that our services are essential and available, as stroke still remains a medical emergency, and carries a likely higher overall mortality risk than COVID-19. As neurologists, we also must be vigilant for the atypical presentations and varied etiologies of stroke associated with COVID-19 as well.

Background and purpose. Power motion mode Doppler (PMD) simultaneously displays flow signal intensity and direction over several centimeters of intracranial space. Insonation protocol for PMD and spectral transcranial Doppler (TCD) with typical PMD flow signatures is described in serial patients with acute stroke symptoms examined via conventional windows with a PMD/ TCD unit. Results. Thirty‐five patients were studied within 12 hours after stroke onset (age 64 ±15 years; 8 received intravenous and 3 intra‐arterial thrombolysis). One patient had no temporal window, and 3 patients had suboptimal windows. In 90% of patients, PMD showed more than 1 ipsilateral temporal windows. In 63% of patients (n= 22), PMD simultaneously displayed the entire M1 (65–45 mm) and proximal M2 (45–30 mm) flows, leading to spectral TCD examination of the proximal M2 middle cerebral artery (MCA) in 28 of 35 patients (80%). All patients had sufficient foraminal (depth display = 60–110 mm) and orbital (depth display = 30–80 mm) windows. PMD displayed the entire basilar artery stem (75–100+ mm) in 69% (n= 24) of patients, and the distal basilar flow was detected in all patients by both PMD and TCD. TCD results were normal (12), proximal intracranial stenosis (5), large vessel occlusion (17), and cerebral circulatory arrest (1). Compared to spectral TCD, PMD signatures of similar diagnostic significance were low resistance (vessel identification and recanalization), high resistance (ophthalmic artery identification and distal obstruction), collateral (communicating arteries and leptomeningeal flow), reverberating (circulatory arrest), and branch embolization. Conclusions. PMD is a window‐finding tool and a guide for spectral TCD gate placement. PMD facilitates flow detection in the M2 branches and the distal basilar artery. PMD can demonstrate recanalization of the entire MCA main stem and proximal branches, increase the yield of embolus detection and procedure monitoring, and facilitate abnormal flow pattern recognition.

Background and Purpose. It has been suggested that intravenous tissue plasminogen activator (TPA) would not lyse the large thrombus associated with internal carotid artery (ICA) occlusion and, therefore, would be ineffective in this setting. Vascular imaging, safety, and outcome of TPA therapy for ICA occlusion is not well described. Our goal was to determine the site of occlusion, early recanalization after TPA infusion, and its relationship to outcome. Methods. We reviewed our database of all stroke patients treated with IV TPA between July 1997 and July 1999. We identified all cases with carotid occlusion suggested by transcranial Doppler (TCD) and angiography. Occlusion and recanalization were assessed by site including proximal ICA (prICA), terminal ICA (tICA), and middle cerebral artery (MCA). Baseline National Institutes of Health Stroke Scale (NIHSS) scores and follow‐up Rankin scores were obtained. Results. We treated 20 patients with carotid occlusion (age 63.9 ± 10.8 years, 11 males, 9 females). Time to TPA infusion after stroke onset was 128 ± 66 minutes. Baseline NIHSS scores were 16.4 ± 5.4. Time to follow‐up was 3.5 ± 4.9 months (2 patients were lost to follow‐up). Occlusion sites were prICA 40%, tICA 70%, and concurrent MCA 45%. Multiple sites were involved in 10/20 patients (50%). Among patients with pretreatment and posttreatment vascular imaging studies (n= 18), recanalization in the prICA and tICA was complete in 10%, partial in 16%, and none in 74%. MCA recanalization was complete in 35%, partial in 24%, and none in 41%. At follow‐up, Rankin 0–1 was found in 8 patients (44%), Rankin 2–3 in 3 (17%), and Rankin 4–5 in 3 (17%). Mortality was 22% (n= 4) including 1 fatal intracerebral hemorrhage. Improvement was closely related to resumption of MCA flow (P< .01). Conclusions. Most patients did not recanalize their ICA occlusion after intravenous TPA therapy. However, recanalization of associated proximal MCA clot, found in 45% of our patients, or improved MCA collateral flow was strongly associated with good outcome.

Background and Purpose. The authors establish accuracy parameters of a broad diagnostic battery for bedside transcranial Doppler (TCD) to detect flow changes due to internal carotid artery (ICA) stenosis or occlusion. Methods. The authors prospectively studied consecutive patients with stroke or transient ischemic attack referred for TCD. TCD was performed and interpreted at bedside using a standard insonation protocol. A broad diagnostic battery included major criteria: collateral flow signals, abnormal siphon or terminal carotid signals, and delayed systolic flow acceleration in the middle cerebral artery. Minor criteria included a unilateral decrease in pulsatility index (≤ 0.6 or ≤ 70% of contralateral side), flow diversion signs, and compensatory velocity increase. Angiography or carotid duplex ultrasound (CDU) was used to grade the degree of carotid stenosis using North American criteria. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of TCD findings were determined. Results. Seven hundred and twenty patients underwent TCD, of whom 517 (256 men and 261 women) had angiography and/or CDU within 8.8 ± 0.9 days. Age was 63.1 ± 15.7 years. For a 70% to 99% carotid stenosis or occlusion, TCD had sensitivity of 79.4%, specificity of 86.2%, PPV of 57.0%, NPV of 94.8%, and accuracy of 84.7%. For a 50% to 99% carotid stenosis or occlusion, TCD had sensitivity of 67.5%, specificity of 83.9%, PPV of 54.5%, NPV of 90.0%, and accuracy of 81.6%. TCD detected intracranial carotid lesions with 84.9% accuracy and extracranial carotid lesions with 84.4% accuracy (sensitivity of 88% and 79%, specificity of 85% and 86%, PPV of 24% and 54%, and NPV of 99% and 95%, respectively). The prevalence of the ophthalmic artery flow reversal was 36.4% in patients with ≥ 70% stenosis or occlusion. If present, this finding indicated a proximal ICA lesion location in 97% of these patients. Conclusions. In symptomatic patients, bedside TCD can accurately detect flow changes consistent with hemodynamically significant ICA obstruction; however, TCD should not be a substitute for direct carotid evaluation. Because TCD is sensitive and specific for ≥ 70% carotid stenosis or occlusion in both extracranial and intracranial carotid segments, it can be used as a complementary test to refine other imaging findings and detect tandem lesions.

AbstractBrain ischemia is a process of delayed neuronal cell death, not an instantaneous event. The concept of neuroprotection is based on this principle. Diminished cerebral blood flow initiates a series of events (the “ischemic cascade”) that lead to cell destruction. This ischemic cascade is akin to a spreading epidemic starting from a hypothesized core of ischemia and radiating outward. If intervention occurs early, the process may be halted.Interventions have been directed toward salvaging the ischemic penumbra. Hypothermia decreases the size of the ischemic insult in both anecdotal clinical and laboratory reports. In addition, a wide variety of agents have been shown to reduce infant volume in animal models. Pharmacologic interventions that involve thrombolysis, calcium channel blockade, and cell membrane receptor antagonism have been studied and have been found to be beneficial in animal cortical stroke models. Human trials of neuroprotective therapies have been disappointing. Other than thrombolytics, no agents, have shown an unequivocal benefit. The future of neuroprotection will require a logical extension of what has been learned in the laboratory and previous human trials. A sensible approach to the use of multiple-agent cocktails used in combination with thrombolytics is likely to offer the highest chance for benefit.

The association between the street drug spice (K-2 or herbal incense), a synthetic marijuana, and intracranial hemorrhage (ICH) has not yet been described, but it has with acute ischemic stroke (AIS),1seizure, and myocardial infarction.2Two young patients (31 and 25 years old) independently presented to our hospital with subarachnoid hemorrhage (SAH) after spice inhalation. The first also had 2 large intraparenchymal hemorrhages (IPH); the other also had AIS. Both were previously healthy without hypertension, coagulopathy, bleeding diathesis, thrombocytopenia, intracranial aneurysm, arteriovenous malformation, connective tissue disease, or anticoagulant/antiplatelet medication use.