Jelle Demeestere

Evaluation of hyperacute infarct volume using ASPECTS and brain CT perfusion core volume

Objective: To compare the accuracy of Alberta Stroke Program Early Computed Tomography Score (ASPECTS) and CT perfusion to detect established infarction in acute anterior circulation stroke. Methods: We performed an observational study in 59 acute anterior circulation ischemic stroke patients who underwent brain noncontrast CT, CT perfusion, and MRI within 100 minutes from CT imaging. ASPECTS scores were calculated by 4 blinded vascular neurologists. The accuracy of ASPECTS and CT perfusion core volume to detect an acute MRI diffusion lesion of ≥70 mL was evaluated using receiver operating characteristics analysis and optimum cutoff values were calculated using Youden J. Results: Median ASPECTS score was 8 (interquartile range [IQR] 5–9). Median CT perfusion core volume was 22 mL (IQR 10.4–71.9). Median MRI diffusion lesion volume was 24.5 mL (IQR 10–63.9). No significant difference was found between the accuracy of CT perfusion and ASPECTS (c statistic 0.95 vs 0.87, p value for difference = 0.17). The optimum ASPECTS cutoff score to detect a diffusion-weighted imaging lesion ≥70 mL was <7 (sensitivity 0.74, specificity 0.86, Youden J = 0.60) and the optimum CT perfusion core volume cutoff was ≥50 mL (sensitivity 0.86, specificity 0.97, Youden J = 0.84). The CT perfusion core lesion covered a median of 100% (IQR 86%–100%) of the acute MRI lesion volume (Pearson R = 0.88; R2 = 0.77). Conclusions: We found no significant difference between the accuracy of CT perfusion and ASPECTS to predict hyperacute MRI lesion volume in ischemic stroke.

Validation of the National Institutes of Health Stroke Scale-8 to Detect Large Vessel Occlusion in Ischemic Stroke

BACKGROUNDnPatients with acute ischemic stroke and large vessel occlusion (LVO) may benefit from prehospital identification and transfer to a center offering endovascular therapy.nnnAIMSnWe aimed to assess the accuracy of an existing 8-item stroke scale (National Institutes of Health Stroke Scale-8 [NIHSS-8]) for identification of patients with acute stroke with LVO.nnnMETHODSnWe retrospectively calculated NIHSS-8 scores in a population of consecutive patients with presumed acute stroke assessed by emergency medical services (EMS). LVO was identified on admission computed tomography angiography. Accuracy to identify LVO was calculated using receiver operating characteristics analysis. We used weighted Cohens kappa statistics to assess inter-rater reliability for the NIHSS-8 score between the EMS and the hospital stroke team on a prospectively evaluated subgroup.nnnRESULTSnOf the 551 included patients, 381 had a confirmed ischemic stroke and 136 patients had an LVO. NIHSS scores were significantly higher in patients with LVO (median 18; interquartile range 14-22). The NIHSS-8 score reliably predicted the presence of LVO (area under the receiver operating characteristic curve .82). The optimum NIHSS-8 cutoff of 8 or more had a sensitivity of .81, specificity of .75, and Youden index of .56 for prediction of LVO. The EMS and the stroke team reached substantial agreement (κu2009=u2009.69).nnnCONCLUSIONSnAccuracy of the NIHSS-8 to identify LVO in a population of patients with suspected acute stroke is comparable to existing prehospital stroke scales. The scale can be performed by EMS with reasonable reliability. Further validation in the field is needed to assess accuracy of the scale to identify patients with LVO eligible for endovascular treatment in a prehospital setting.

Experimental surgical therapies for Huntington's disease.

Huntingtons disease (HD) is an autosomal dominant neurodegenerative disorder characterized by abnormal movement, cognitive decline, and psychiatric disturbance. HD is caused by a trinucleotide repeat expansion in the HTT gene and a corresponding neurotoxic polyglutamine expansion in the huntingtin protein. There is currently no therapy to modify the progressive course of the disease, and symptomatic treatment options are limited. In this review we describe a diverse set of emerging experimental therapeutic strategies for HD: deep brain stimulation; delivery of neurotrophic factors; cell transplantation; HTT gene silencing using RNA interference or antisense oligonucleotides; and delivery of intrabodies. The common feature of these experimental therapies is that they all require a neurosurgical intervention, either for implantation of an electrode or for brain delivery of molecules, viruses or cells that do not cross the blood–brain barrier upon oral or intravenous administration. We summarize available data on the rationale, safety, efficacy, and intrinsic limitations of each of these approaches, focusing mainly on studies in HD patients and genetic animal models of HD. Although each of these strategies holds significant promise, their efficacy remains to be proven in HD patients.

Detection of Atrial Fibrillation Among Patients With Stroke Due to Large or Small Vessel Disease: A Meta‐Analysis

Background Recent trials have demonstrated that extended cardiac monitoring increases the yield of paroxysmal atrial fibrillation (AF) detection in patients with cryptogenic stroke. The utility of extended cardiac monitoring is uncertain among patients with stroke caused by small and large vessel disease. We conducted a meta‐analysis to estimate the yield of AF detection in this population. Methods and Results We searched PubMed, Cochrane, and SCOPUS databases for studies on AF detection in stroke patients and excluded studies restricted to patients with cryptogenic stroke or transient ischemic attack. We abstracted AF detection rates for 3 populations grouped by stroke etiology: large vessel stroke, small vessel stroke, and stroke of undefined etiology (a mixture of cryptogenic, small vessel, large vessel, and other stroke etiologies). Our search yielded 30 studies (n=5687). AF detection rates were similar in patients with large vessel (2.2%, 95% CI 0.3–5.5; n=830) and small vessel stroke (2.4%, 95% CI 0.4–6.1; n=520). No studies had a monitoring duration longer than 7 days. The yield of AF detection in the undefined stroke population was higher (9.2%; 95% CI 7.1–11.5) compared to small vessel stroke (P=0.02) and large vessel stroke (P=0.02) populations. Conclusions AF detection rate is similar in patients with small and large vessel strokes (2.2–2.4%). Because no studies reported on extended monitoring (>7 days) in these stroke populations, we could not estimate the yield of AF detection with long‐term cardiac monitoring. Randomized controlled trials are needed to examine the utility of AF detection with long‐term cardiac monitoring (>7 days) in this patient population.

The validation of simplified EEG derived from the bispectral index monitor in post-cardiac arrest patients

AIMSnWe aimed to validate retrospectively the accuracy of simplified electroencephalography (EEG) monitoring derived from the bispectral index (BIS) monitor in post-cardiac arrest (CA) patients.nnnMETHODSnSuccessfully resuscitated CA patients were transferred to the Catherization Lab followed by percutaneous coronary intervention when indicated. On arrival at the coronary care unit, bilateral BIS monitoring was started and continued up to 72u202fh. Raw simplified EEG tracings were extracted from the BIS monitor at a time point coinciding with the registration of standard EEG monitoring. BIS EEG tracings were reviewed by two neurophysiologists, who were asked to indicate the presence of following patterns: diffuse slowing rhythm, burst suppression pattern, cerebral inactivity, periodic epileptiform discharges and status epilepticus (SE). Additionally, these simplified BIS EEG tracings were analysed by two inexperienced investigators, who were asked to indicate the presence of SE only.nnnRESULTSnThirty-two simplified BIS EEG samples were analysed. Compared to standard EEG, neurophysiologists interpreted all simplified EEG samples with a sensitivity of 86%, a specificity of 100% and an interobserver variability of 0.843. Furthermore, SE was identified with a sensitivity of 80% and a specificity of 94% by two unexperienced physicians.nnnCONCLUSIONnUsing a simple classification system, raw simplified EEG derived from a BIS monitoring device is comparable to standard EEG monitoring. Moreover, investigators without EEG experience were capable to identify SE in post-CA patients. Future studies will be warranted to confirm our results and to determine the added value of using simplified BIS EEG in terms of prognostic and therapeutic implications.

Prognostic Value of BEFAST vs. FAST to Identify Stroke in a Prehospital Setting

Abstract Background: Use of prehospital stroke scales may enhance stroke detection and improve treatment rates and delays. Current scales, however, may lack detection accuracy. As such, we examined whether adding coordination (Balance) and diplopia (Eyes) assessments increase the accuracy of the Face-Arms-Speech-Time (FAST) scale in a multisite prospective study of emergency response activations for presumed stroke. Methods: This was a prospective study of emergency response activations for presumed stroke in Santa Clara County, California. Emergency medical responders were trained in the Balance-Eyes-Face-Arms-Speech-Time (BEFAST) scale and administered the scale on scene to all patients who were within 6u2009hours of onset of neurological symptoms. Each patient’s final diagnosis (stroke vs. no stroke) was based on review of hospital records. We compared the performance of the BEFAST and FAST scales for stroke detection. Results: Three hundred fifty-nine patients were included in our analysis. Compared to nonstroke patients (nu2009=u2009200), stroke patients (nu2009=u2009159) more often scored positive on each of the five elements of the BEFAST scale (pu2009<u20090.05 for each). In multivariable analysis, only facial droop and arm weakness were independent predictors of stroke (pu2009<u20090.05). BEFAST and FAST scale accuracy for stroke identification was comparable (area under the curve [AUC]u2009=u20090.70 vs. AUCu2009=u20090.69, pu2009=u20090.36). Optimal cutoff for stroke detection was ≥1 for both scales. At this threshold, the positive predictive value (PPV) was 0.49 for the BEFAST and 0.53 for the FAST scale, and the negative predictive value (NPV) was 0.93 for BEFAST and 0.86 for FAST. Conclusion: Adding coordination and diplopia assessments to face, arm, and speech assessment does not improve stroke detection in the prehospital setting.

The Prognostic Value of Simplified EEG in Out-of-Hospital Cardiac Arrest Patients

BackgroundWe previously validated simplified electroencephalogram (EEG) tracings obtained by a bispectral index (BIS) device against standard EEG. This retrospective study now investigated whether BIS EEG tracings can predict neurological outcome after cardiac arrest (CA).MethodsBilateral BIS monitoring (BIS VISTA™, Aspect Medical Systems, Inc. Norwood, USA) was started following intensive care unit admission. Six, 12, 18, 24, 36 and 48xa0h after targeted temperature management (TTM) at 33xa0°C was started, BIS EEG tracings were extracted and reviewed by two neurophysiologists for the presence of slow diffuse rhythm, burst suppression, cerebral inactivity and epileptic activity (defined as continuous, monomorphic, >u20092xa0Hz generalized sharp activity or continuous, monomorphic, <u20092xa0Hz generalized blunt activity). At 180xa0days post-CA, neurological outcome was determined using cerebral performance category (CPC) classification (CPC1-2: good and CPC3-5: poor neurological outcome).ResultsSixty-three out-of-hospital cardiac arrest patients were enrolled for data analysis of whom 32 had a good and 31 a poor neurological outcome. Epileptic activity within 6–12xa0h predicted CPC3-5 with a positive predictive value (PPV) of 100%. Epileptic activity within time frames 18–24 and 36–48xa0h showed a PPV for CPC3-5 of 90 and 93%, respectively. Cerebral inactivity within 6–12xa0h predicted CPC3-5 with a PPV of 57%. In contrast, cerebral inactivity between 36 and 48xa0h predicted CPC3-5 with a PPV of 100%. The pattern with the worst predictive power at any time point was burst suppression with PPV of 44, 57 and 40% at 6–12xa0h, at 18–24xa0h and at 36–48xa0h, respectively. Slow diffuse rhythms at 6–12xa0h, at 18–24xa0h and at 36–48xa0h predicted CPC1-2 with PPV of 74, 76 and 80%, respectively.ConclusionBased on simplified BIS EEG, the presence of epileptic activity at any time and cerebral inactivity after the end of TTM may assist poor outcome prognostication in successfully resuscitated CA patients. A slow diffuse rhythm at any time after CA was indicative for a good neurological outcome.

Cerebral microbleeds and intracerebral hemorrhage associated with veno-venous extracorporeal membrane oxygenation

A 30-year-old woman, 26-week pregnant, was admitted to the intensive care unit (ICU) with an influenza-A pneumonia and severe acute respiratory distress syndrome (ARDS). She deteriorated while on protective lung ventilation, steroids and intermittent proning. Day 4, an emergency caesarian section was performed, followed by initiation of venovenous extracorporeal membrane oxygenation (ECMO). ECMO was continued for 12 days. She was extubated 2 days later. 1 week after extubation she had a tonic–clonic epileptic seizure, treated with diazepam and levetiracetam. On brain computed tomography (CT), a hyperdense lesion with surrounding edema in the right parietal lobe was seen (Fig. 1). Magnetic resonance imaging (MRI) showed multiple microbleeds (MB) at the cortico-subcortical junction and deep white matter, and one larger hemorrhage in the right parietal cortex, which caused the seizure (Fig. 2). The patient was discharged home after 1 month and remained seizure free under levetiracetam 500 mg bd. The baby is still in the neonatal ICU. MB are small (< 10 mm), round and hypo-intense lesions readily visible on gradient-recall echo or susceptibilityweighted MRI which are often invisible on CT [1]. Histopathologically, they correspond to areas of hemosiderin deposition as a result of prior self-limiting microhemorrhage usually secondary to small vessel disease [1]. However, diffuse MB at the cortico-subcortical junction and the corpus

Author response: Evaluation of hyperacute infarct volume using ASPECTS and brain CT perfusion core volume

We thank Das et al. and Compagne et al. for the interest in our article.1

The establishment of a telestroke service using multimodal CT imaging decision assistance: "Turning on the fog lights".

Telestroke services have been shown to increase stroke therapy access in rural areas. The implementation of advanced CT imaging for patient assessment may improve patient selection and detection of stroke mimics in conjunction with telestroke. We implemented a telestroke service supported by multimodal CT imaging in a rural hospital in Australia. Over 21months we conducted an evaluation of service activation, thrombolysis rates and use of multimodal imaging to assess the feasibility of the service. Rates of symptomatic intracranial haemorrhage and 90-day modified Rankin Score were used as safety outcomes. Fifty-eight patients were assessed using telestroke, of which 41 were regarded to be acute ischemic strokes and 17 to be stroke mimics on clinical grounds. Of the 41 acute stroke patients, 22 patients were deemed eligible for thrombolysis. Using multimodal CT imaging, 8 more patients were excluded from treatment because of lack of treatment target. Multimodal imaging failed to be obtained in one patient. For the 14 treated patients, median door-imaging time was 38min. Median door-treatment time was 91min. A 90-day mRS ⩽2 was achieved in 40% of treated patients. We conclude that a telestroke service using advanced CT imaging for therapy decision assistance can be successfully implemented in regional Australia and can be used to guide acute stroke treatment decision-making and improve access to thrombolytic therapy. Efficiency and safety is comparable to established telestroke services.