Stroke Mimics in a Stroke Care Pathway Based on MRI Screening

Non-Contrast MRI Sequences for Ischemic Stroke: A Concise Overview for Clinical Radiologists

Ischemic stroke is the second leading cause of mortality and morbidity worldwide. Due to the urgency of implementing immediate therapy, acute stroke necessitates prompt diagnosis. The current gold standards for vascular imaging in stroke include computed tomography angiography (CTA), digital subtraction angiography (DSA) and magnetic resonance angiography (MRA). However, the contrast agents used in these methods can be costly and pose risks for patients with renal impairment or allergies. The aim of this paper is to provide a comprehensive overview of current MRI techniques and sequences for evaluating ischemic stroke, emphasizing the importance of non-contrast options and their clinical implications for radiologists in the diagnosis and management of ischemic stroke. Standard MRI sequences-such as T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), fluid-attenuated inversion recovery (FLAIR), diffusion-weighted imaging (DWI), DWI-FLAIR mismatch, and apparent diffusion coefficient (ADC)-are essential for determining infarct location, volume, and age. Additionally, incorporating susceptibility-weighted imaging (SWI) sequence aids in identifying signs of hemorrhagic transformation within the infarcted region. Advanced techniques like arterial spin labeling (ASL) can serve as a non-contrast alternative for mapping cerebral blood flow (CBF) and allowing for comparison between infarcted and healthy brain areas. Adding ASL to the routine sequence allows ASL-DWI mismatch analysis that is useful for quantifying salvageable tissue volume and facilitate timely recanalization, while time-of-flight (TOF) MRA and magnetic resonance venography (MRV) help assess venous thrombosis, stenosis, or arterial occlusions. Finally, MR spectroscopy can provide insights into critical brain metabolites, including N-acetylaspartate (NAA), and lactate (Lac) to determine patient prognosis. Current MRI technology provides a myriad of sequence options for the comprehensive evaluation of ischemic stroke without the need for contrast material. A thorough understanding of the advantages and limitations of each sequence is crucial for its optimal implementation in diagnosis and treatment.

Moving From CT to MRI Paradigm in Acute Ischemic Stroke: Feasibility, Effects on Stroke Diagnosis and Long-Term Outcomes

BACKGROUND

The relative value of computed tomography (CT) and magnetic resonance imaging (MRI) in acute ischemic stroke (AIS) is debated. In May 2018, our center transitioned from using CT to MRI as first-line imaging for AIS. This retrospective study aims to assess the effects of this paradigm change on diagnosis and disability outcomes.

METHODS

We compared all consecutive patients with confirmed diagnosis of AIS admitted to our center during the MRI-period (May 2018-August 2022) and an identical number of patients from the preceding CT-period (December 2012-April 2018). Univariable and multivariable analyses were performed to evaluate outcomes, including the number and delay of imaging exams, the rate of missed strokes, stroke mimics treated with thrombolysis, undetermined stroke mechanisms, length of hospitalization, and 3-month disability.

RESULTS

The median age of the 2972 included patients was 76 years (interquartile range, 65-84), and 46% were female. In the MRI-period, 80% underwent MRI as first acute imaging. The proportion of patients requiring a second acute imaging modality for diagnostic ± revascularization reasons increased from 2.1% to 5% (Punadj <0.05), but it decreased in the subacute phase from 79.0% to 60.1% (Padj <0.05). In thrombolysis candidates, there was a 2-minute increase in door-to-imaging delay (Padj <0.05). The rates of initially missed AIS diagnosis was similar (3.8% versus 4.4%, Padj=0.32) and thrombolysis in stroke mimics decreased by half (8.6% versus 4.3%; Padj <0.05). Rates of unidentified stroke mechanism at hospital discharge were similar (22.8% versus 28.1%; Padj=0.99). The length of hospitalization decreased from 9 (interquartile range, 6-14) to 7 (interquartile range, 4-12) days (Padj=0.62). Disability at 3 months was similar (common adjusted odds ratio for favorable Rankin shift, 0.98 [95% CI, 0.71-1.36]; Padj=0.91), as well as mortality and symptomatic intracranial hemorrhage.

CONCLUSIONS

A paradigm shift from CT to MRI as first-line imaging for AIS seems feasible in a comprehensive stroke center, with a minimally increased delay to imaging in thrombolysis candidates. MRI was associated with reduced thrombolysis rates of stroke mimics and subacute neuroimaging needs.

Quality control in treating patients with patent foramen ovale: 7-year-experience of the Heart and Brain team of the Careggi University Hospital

BACKGROUND

The right comprehension of ischemic stroke pathogenesis guarantees the best prevention therapy. The term "patent foramen ovale (PFO) related stroke" has been proposed for those events where PFO is supposed to be pathogenetic, but their definition is challenging. A multidisciplinary evaluation in a "Heart & Brain" team (HBteam) including stroke neurologists and interventional cardiologists was therefore highly recommended in the recent guidelines of secondary stroke prevention.

OBJECTIVE

We aimed at describing the organization of the HBteam of Careggi-University-Hospital of Florence (Italy), and the results of the first seven years of activity.

METHODS

In 2016 Interventional Cardiologists and Stroke Neurologists set up an outpatient clinic for the joined evaluation of patients with PFO and other cardio/neurological conditions. A specific diagnostic-therapeutic hospital plan was produced for PFO patients. Patient empowerment was guaranteed by a hospital explicative webpage, a booklet regarding risks/benefits of PFO closure and a 3D heartmodel to simulate the intervention. Data were collected in a dedicated registry.

RESULTS

We evaluated 594 patients for PFO, 40 for left atrial appendage closure and 38 for other conditions. In 20% of PFO-patients, HBteam diagnosis was discordant from that of referring physicians, 14% were stroke misdiagnoses. We advised against closure in 53% of patients. At follow-up 94% of closed patients had no/minimum residual shunt; 3 patients had a cerebral ischemic event.

CONCLUSIONS

A dedicated HBteam represents a unique opportunity to share decisions with patients after a thorough empowerment process. The joining of cardioneurological skills allows a better classification of PFO-patients, reducing futile interventions.

Frequency and Characteristics of Non-Neurological and Neurological Stroke Mimics in the Emergency Department

BACKGROUND

Stroke mimics are common in the emergency department (ED) and early detection is important to initiate appropriate treatment and withhold unnecessary procedures. We aimed to compare the frequency, clinical characteristics and predictors of non-neurological and neurological stroke mimics transferred to our ED for suspected stroke.

METHODS

This was a cross-sectional study of consecutive patients with suspected stroke transported to the ED of the University Hospital Essen between January 2017 and December 2021 by the city's Emergency Medical Service. We investigated patient characteristics, preclinical data, symptoms and final diagnoses in patients with non-neurological and neurological stroke mimics. Multinominal logistic regression analysis was performed to assess predictors of both etiologic groups.

RESULTS

Of 2167 patients with suspected stroke, 762 (35.2%) were diagnosed with a stroke mimic. Etiology was non-neurological in 369 (48.4%) and neurological in 393 (51.6%) cases. The most common diagnoses were seizures (23.2%) and infections (14.7%). Patients with non-neurological mimics were older (78.0 vs. 72.0 y, p < 0.001) and more likely to have chronic kidney disease (17.3% vs. 9.2%, p < 0.001) or heart failure (12.5% vs. 7.1%, p = 0.014). Prevalence of malignancy (8.7% vs. 13.7%, p = 0.031) and focal symptoms (38.8 vs. 57.3%, p < 0.001) was lower in this group. More than two-fifths required hospitalization (39.3 vs. 47.1%, p = 0.034). Adjusted multinominal logistic regression revealed chronic kidney and liver disease as independent positive predictors of stroke mimics regardless of etiology, while atrial fibrillation and hypertension were negative predictors in both groups. Prehospital vital signs were independently associated with non-neurological stroke mimics only, while age was exclusively associated with neurological mimics.

CONCLUSIONS

Up to half of stroke mimics in the neurological ED are of non-neurological origin. Preclinical identification is challenging and a high proportion requires hospitalization. Awareness of underlying etiologies and differences in clinical characteristics is important to provide optimal care.

Sex Differences in Neurological Emergencies Presenting to Multiple Urban Level 1 Trauma Centers

Previous studies have suggested that there are sex differences in the treatment and outcome of neurological emergencies; however, research identifying the role these sex differences play in the management of neurological emergencies is lacking. More knowledge of the way sex factors into the pathophysiology of neurological emergencies will be helpful in improving outcomes for these patients. The aim of this cross-sectional study was to assess the prevalence and management of neurological emergencies while evaluating sex differences in the diagnosis and treatment of these emergencies. We analyzed a cohort of 530 adult patients from four level 1 trauma centers over a period of 4 weeks who had a chief complaint of a neurological emergency, including seizures, cerebrovascular events, headache disorders, traumatic brain injuries, and central nervous system infections. Among patients with neurological emergencies, a significantly lower proportion of female patients underwent neurosurgery and were admitted to the intensive care unit compared to male patients, but there were no significant differences between sexes in the time of symptom onset, type of hospital transportation, amount of neuroimaging performed, admission rates, hospital length of stay, and disposition from the emergency department. Although female patients were more likely to have a chief complaint of headache compared to traumatic injuries in male patients, this was not statistically significant. A significantly higher proportion of female patients had health insurance coverage than male patients.

Diagnostic accuracy of telestroke consultation: a Louisiana based tele-network experience

Background and purpose

Telestroke has grown significantly since its implementation. Despite growing utilization, there is a paucity of data regarding the diagnostic accuracy of telestroke to distinguish between stroke and its mimics. We aimed to evaluate diagnostic accuracy of telestroke consultations and explore the characteristics of misdiagnosed patients with a focus on stroke mimics.

Methods

We conducted a retrospective study of all the consultations in our Ochsner Health's TeleStroke program seen between April 2015 and April 2016. Consultations were classified into one of three diagnostic categories: stroke/transient ischemic attack, mimic, and uncertain. Initial telestroke diagnosis was compared with the final diagnosis post review of all emergency department and hospital data. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+) and negative likelihood ratio (LR-) for diagnosis of stroke/TIA versus mimic were calculated. Area under receiver-operating characteristic curve (AUC) analysis to predict true stroke was performed. Bivariate analysis based on the diagnostic categories examined association with sex, age, NIHSS, stroke risk factors, tPA given, bleeding after tPA, symptom onset to last known normal, symptom onset to consult, timing in the day, and consult duration. Logistic regression was performed as indicated by bivariate analysis.

Results

Eight hundred and seventy-four telestroke evaluations were included in our analysis. Accurate diagnosis through teleneurological consultation was seen in 85% of which 532 were strokes (true positives) and 170 were mimics (true negatives). Sensitivity, specificity, PPV, NPV were 97.8, 82.5, 93.7 and 93.4%, respectively. LR+ and LR- were 5.6 and 0.03. AUC (95% CI) was 0.9016 (0.8749-0.9283). Stroke mimics were more common with younger age and female gender and in those with less vascular risk factors. LR revealed OR (95% CI) of misdiagnosis for female gender of 1.9 (1.3-2.9). Lower age and lower NIHSS score were other predictors of misdiagnosis.

Conclusion

We report high diagnostic accuracy of the Ochsner Telestroke Program in discriminating stroke/TIA and stroke mimics, with slight tendency towards over diagnosis of stroke. Female gender, younger age and lower NIHSS score were associated with misdiagnosis.

Visual symptoms in acute stroke - A systematic review of observational studies

OBJECTIVE

Atypical symptoms of stroke, such as non-specific visual symptoms, are a challenging aspect of acute stroke diagnostics. Among patients evaluated for stroke in the Emergency Department, 2-28% present with stroke chameleons, and 30-43% with stroke mimics. We aimed to identify the type of visual symptoms present in typical strokes, stroke mimics, and stroke chameleons.

PATIENTS AND METHODS

By use of Preferred Reporting Items for Systematic Reviews and Meta-Analysis we searched PubMed and Embase for studies with reports of acute visual symptoms in typical strokes vs mimics or chameleons (PROSPERO protocol, ID CRD42022364749). Risk of bias was assessed by The Critical Appraisal Skills Program.

RESULTS

Thirteen papers were included, comprising data from 9248 patients evaluated for stroke. Compared to mimics, visual symptoms in stroke presented more frequently as hemianopia (28.2% vs 4.8%, 7,4% vs 2.3%, 22% vs 0%), visual loss (11.6% vs 1.8%), visual field defect (11.6% vs 4%, 24% vs 2%, 19% vs 1.7%), eye movement disorder (19.4% vs 6.4%), eye deviation (9.6% vs 0.9%), gaze palsy (32.1% vs 8.6%), oculomotor disturbance (37% vs 0%), and visual inattention (17.5% vs 4%). Compared to strokes, mimics more often presented "non-systematized visual trouble" (10% vs 3%) and blurred vision (22% vs 5%), whereas "visual disturbance" was reported more often in stroke chameleons than in typical strokes (10% vs 3%).

CONCLUSION

Detailed reports of visual symptoms were lacking in most studies, however blurred vision and "non-systematized visual trouble" were more frequent in mimics, "visual disturbance" in stroke chameleons, and negative visual symptoms such as visual field defects in typical strokes. A more systematic and detailed approach to visual symptoms may facilitate acute stroke recognition in patients with visual symptoms.

Diagnostic utility of T2*-weighted GRE in migraine with aura attack. The cortical veins sign

OBJECTIVE

To evaluate the frequency, distribution, and clinical associations of the dilated appearance of cerebral cortical veins, termed cortical veins sign on T2*-weighted gradient recalled-echo (T2*-GRE) in the acute setting of migraine with aura attack in adult patients.

METHODS

We conducted a retrospective analysis of 60 consecutive patients admitted for acute neurological symptoms with a final diagnosis of migraine with aura (42%) or probable migraine with aura (58%) who underwent emergency brain magnetic resonance imaging and 60 non-migrainous control adults. The cortical veins sign was defined as a marked hypo-intensity and/or an apparent increased diameter of at least one cortical vein. We examined the prevalence, the spatial distribution, and the associations of cortical veins sign with clinical characteristics of migraine with aura.

RESULTS

We detected the cortical veins sign in 25 patients (42%) with migraine with aura, compared to none in the control group (p < 0.0001). The spatial distribution of cortical veins sign was characterised by the predominantly bilateral and posterior location. Presence of cortical veins sign was associated with increased severity of aura (p = 0.05), and shorter delay to MRI (p = 0.02).

CONCLUSION

In the setting of acute neurological symptoms, the presence of cortical veins sign is frequent in patients with migraine with aura and can be detected with good reliability. This imaging marker may help clinicians identify underlying migraine with aura.

Stroke mimics: incidence, aetiology, clinical features and treatment

Mimics account for almost half of hospital admissions for suspected stroke. Stroke mimics may present as a functional (conversion) disorder or may be part of the symptomatology of a neurological or medical disorder. While many underlying conditions can be recognized rapidly by careful assessment, a significant proportion of patients unfortunately still receive thrombolysis and admission to a high-intensity stroke unit with inherent risks and unnecessary costs. Accurate diagnosis is important as recurrent presentations may be common in many disorders. A non-contrast CT is not sufficient to make a diagnosis of acute stroke as the test may be normal very early following an acute stroke. Multi-modal CT or magnetic resonance imaging (MRI) may be helpful to confirm an acute ischaemic stroke and are necessary if stroke mimics are suspected. Treatment in neurological and medical mimics results in prompt resolution of the symptoms. Treatment of functional disorders can be challenging and is often incomplete and requires early psychiatric intervention.

Stroke Mimics on the Stroke Unit - Temporal trends 2008-2017 at a large Norwegian university hospital

OBJECTIVES

The objective was to quantify temporal trends in stroke mimics (SM) admissions relative to cerebrovascular accidents (CVA), incidence of hospitalized SMs and characterize the SM case-mix at a general hospital's stroke unit (SU).

MATERIALS & METHODS

All SU admissions (n = 11240) of patients aged 15 or older to Haukeland University Hospital between 2008-2017 were prospectively included and categorized as CVA or SM. Logistic regression was used to estimate time trends in the proportion of SMs among the admissions. Poisson regression was used to estimate time trends in age- and sex-dependent SM incidence.

RESULTS

SMs were on average younger thaan CVA patients (68.3 vs. 71.4 years) and had a higher proportion of females (53.6% vs. 44.5%). The total proportion of SM admissions was 51.0%. There was an increasing time trend in the proportion of SM admissions, odds ratio 1.150 per year (p < 0.001), but this trend appears flattening, represented by a significant quadratic time-term, odds ratio 1.009 (p < 0.001). A higher SM proportion was also associated with the time period of a Mass Media Intervention (FAST campaign) in 2014. There was also an increasing trend in SM incidence, that remains after adjusting for age, sex, and population; also, for incidence the trend appears to be flattening.

CONCLUSIONS

SMs account for approximately half of the SU admissions, and the proportion has been increasing. A FAST campaign appears to have temporarily increased the SM proportion. The age- and sex-dependent incidence of SM has been increasing but appears to flatten out.

Role of imaging in early diagnosis of acute ischemic stroke: a literature review

Stroke is a serious health condition that is responsible for more than 5% of total deaths. Near 20% of patients experiencing stroke die every year, resulting in the stroke being at the top of the list of preventable causes of death. Once an acute stroke is suspected, a golden hour of less than an hour is available to prevent the undesirable consequences. Since neuroimaging is mandatory in the diagnosis of stroke, the proper use of neuroimaging could help saving time and planning the right treatment for the patient. Some of the available imaging methods help us with rapid results, while others benefit us from a more accurate diagnosis. Hereby, we aim to provide a clinical review of the advantages and disadvantages of different available neuroimaging methods in approaching acute stroke to help clinicians choose the best method according to the settings.

Ischemic stroke mimics: A comprehensive review

BACKGROUND

Ischemic stroke is the leading cause of disability and one of the leading causes of death. Ischemic stroke mimics (SMs) can account for a noteble number of diagnosed acute strokes and even can be thrombolyzed.

METHODS

The aim of our comprehensive review was to summarize the findings of different studies focusing on the prevalence, type, risk factors, presenting symptoms, and outcome of SMs in stroke/thrombolysis situations.

RESULTS

Overall, 61 studies were selected with 62.664 participants. Ischemic stroke mimic rate was 24.8% (15044/60703). Most common types included peripheral vestibular dysfunction in 23.2%, toxic/metabolic in 13.2%, seizure in 13%, functional disorder in 9.7% and migraine in 7.76%. Ischemic stroke mimic have less vascular risk factors, younger age, female predominance, lower (nearly normal) blood pressure, no or less severe symptoms compared to ischemic stroke patients (p < 0.05 in all cases). 61.7% of ischemic stroke patients were thrombolysed vs. 26.3% among SMs (p < 0.001). (p < 0.001). Overall intracranial hemorrhage was reported in 9.4% of stroke vs. 0.7% in SM patients (p < 0.001). Death occurred in 11.3% of stroke vs 1.9% of SM patients (p < 0.001). Excellent outcome was (mRS 0-1) was reported in 41.8% ischemic stroke patients vs. 68.9% SMs (p < 0.001). Apart from HINTS manouvre or Hoover sign there is no specific method in the identification of mimics. MRI DWI or perfusion imaging have a role in the setup of differential diagnosis, but merit further investigation.

CONCLUSION

Our article is among the first complex reviews focusing on ischemic stroke mimics. Although it underscores the safety of thrombolysis in this situation, but also draws attention to the need of patient evaluation by physicians experienced in the diagnosis of both ischemic stroke and SMs, especially in vertigo, headache, seizure and conversional disorders.

Migraine with Aura as a Stroke Mimic

Migraine with aura is one of the causes of stroke mimics. We retrospectively reviewed the 10-year medical records of patients who were treated with acute stroke management protocol. We analyzed the frequency and characteristics of patients with a final diagnosis of migraine with aura. Among the 1355 patients with stroke mimics, migraine with aura was the final diagnosis in 36 patients (2.7%). The most common auras included sensory and brainstem auras followed by motor, visual, and speech/language auras. One patient manifested transient atrial fibrillation during the migraine attack, which can be a link with acute stroke.

Role of neuroimaging before reperfusion therapy. Part 1 - IV thrombolysis - Review

This review paper summarises the yield of the different imaging modalities in the evaluation of patients for IV thrombolysis. Non-contrast CT and CTA or brain MRI combined with MRA are the recommended sequences for the evaluation of patients within the 4.5 hours time window. Multimodal MRI (DWI/PWI), and more recently, CT perfusion, offer reliable surrogate of salvageable penumbra, the target mismatch, which is now currently used as selection criteria for revascularisation treatment in an extended time window. Those sequences may also help the physician for the management of other limited cases when the diagnosis of acute ischemic stroke is difficult. Another approach the DWI/FLAIR mismatch has been proposed to identify among wake-up stroke patients those who have been experiencing an acute ischemic stroke evolving from less than 4.5hrs. Other biomarkers, such as the clot imaging on MRI and CT, help to predict the recanalisation rate after IVT, while the impact of the presence microbleeds on MRI remains to be determined.

Acute Ischemic Stroke or Epileptic Seizure? Yield of CT Perfusion in a "Code Stroke" Situation

BACKGROUND AND PURPOSE

The clinical differentiation between acute ischemic stroke and epileptic seizure may be challenging, and making the correct diagnosis could avoid unnecessary reperfusion therapy. We examined the accuracy of CTP in discriminating epileptic seizures from acute ischemic stroke without identified arterial occlusion.

MATERIALS AND METHODS

We retrospectively identified consecutive patients in our emergency department who underwent CTP in the 4.5 hours following the development of an acute focal neurologic deficit who were discharged with a final diagnosis of acute ischemic stroke or epileptic seizure.

RESULTS

Among 95 patients, the final diagnosis was epileptic seizure in 45 and acute ischemic stroke in 50. CTP findings were abnormal in 73% of the patients with epileptic seizure and 40% of those with acute ischemic stroke. Hyperperfusion was observed more frequently in the seizure group (36% versus 2% for acute ischemic stroke) with high specificity (98%) but low sensitivity (35%) for the diagnosis of epileptic seizure. Hypoperfusion was found in 38% of cases in each group and was not confined to a vascular territory in 24% of patients in the seizure group and 2% in the acute ischemic stroke group. The interobserver agreement was good (κ = 0.60) for hypo-, hyper-, and normoperfusion patterns and moderate (κ = 0.41) for the evaluation of vascular systematization.

CONCLUSIONS

CTP patterns helped to differentiate acute ischemic stroke from epileptic seizure in a "code stroke" situation. Our results indicate that a hyperperfusion pattern, especially if not restricted to a vascular territory, may suggest reconsideration of intravenous thrombolysis therapy.

Patients With Acute Ischemic Stroke Who Receive Brain Magnetic Resonance Imaging Demonstrate Favorable In-Hospital Outcomes

Background

Use of inpatient brain magnetic resonance imaging (MRI) in patients with acute ischemic stroke is highly institution dependent and has been associated with increased length and cost of hospital stay. We examined whether inpatient brain MRI in patients with acute ischemic stroke is associated with improved clinical outcomes to justify its resource requirements.

Methods and Results

The National Inpatient Sample database was queried retrospectively to find 94 003 patients who were admitted for acute ischemic stroke and then received inpatient brain MRI between 2012 and 2014. Multivariable regression analysis was performed with respect to a control group to assess for differences in the rates of inpatient mortality and complications, as well as the length and cost of hospital stay based on brain MRI use. Inpatient brain MRI was independently associated with lower rates of inpatient mortality (1.67% versus 3.09%; adjusted odds ratio [OR], 0.60; 95% CI, 0.53–0.68; P<0.001), gastrostomy (2.28% versus 2.89%; adjusted OR, 0.82; 95% CI, 0.73–0.93; P<0.001), and mechanical ventilation (1.97% versus 2.82%; adjusted OR, 0.68; 95% CI, 0.60–0.77; P<0.001). Brain MRI was independently associated with ≈0.32 days (8%) and $1131 (11%) increase in the total length (P<0.001) and cost (P<0.001) of hospital stay, respectively.

Conclusions

Inpatient brain MRI in patients with acute ischemic stroke is associated with substantial decrease in the rates of inpatient mortality and complications, at the expense of marginally increased length and cost of hospitalization.

Stroke-mimics in stroke-units. Evaluation after changes imposed by randomized trials

BACKGROUND

A larger therapeutic window for stroke treatment requires a significant change in the organization of emergency services, avoiding the increase in number of imaging exams and indirectly the time to treatment.

OBJECTIVE

To highlight the relation between faster clinical evaluation and stroke over-suspicion and consequently excessive imaging acquisition. To identify predictors of ischemic stroke and stroke mimics (SM), aiming for better patient selection for comprehensive neuroimaging and reperfusion therapies.

METHODS

Retrospective, cohort, observational, single-center study that reviewed all consecutive files of patients presenting with acute neurological symptoms who underwent CT scan or MRI from July 1, 2016 to July 1, 2017.

RESULTS

736 patient files were reviewed. 385 patients (52.3%) presented with confirmed acute ischemic infarct, 93 (12.6%) had another brain lesion mimicking acute ischemia, and 258 (35.1%) had normal imaging. Acute stroke was more frequent in elderly patients with atrial fibrillation, arterial hypertension, or dysarthria or right motor impairment. Stroke mimic was associated with female patients with low vascular risk factors, low NIHSS, and patients with decreased level of consciousness or symptoms suggestive of posterior circulation.

DISCUSSION

47.7% of all patients seen at the stroke unit did not have acute stroke lesions. Clinical assessment data have been used to provide indicators of acute stroke and stroke mimic patients, and symptoms corresponding to acute stroke and stroke mimic seem to be similar in the literature.

CONCLUSION

Considering that the number of patients admitted for stroke treatment will increase even further with a larger therapeutic window for mechanical thrombectomy and for thrombolysis, a diagnostic decision-making algorithm for stroke patients is required in order to reinforce the suspicion of stroke indicating an urgent MRI.

Status epilepticus mimicking stroke recurrence

AIM OF THE STUDY

The aim of the study was to evaluate the clinical characteristics of patients with previous stroke (either ischemic or hemorrhagic), who developed status epilepticus (SE) mimicking a stroke relapse.

MATERIALS AND METHODS

We performed a retrospective cohort study of patients brought to hospital by the emergency service between December 2016 and January 2018 with a stroke code as possible candidates for intravenous thrombolysis and who had already have a previous stroke. Among them, patients admitted for negative symptoms and finally discharged with a diagnosis of SE mimicking stroke were selected and their clinical characteristics collected. All patients underwent routine blood sample analysis, head computed tomography (CT) scan and, when indicated, CT angiography and CT-perfusion imaging of the head. After admission in our stroke unit, an Electroencephalogram (EEG) was performed within 3 h in patients suspected with SE, then classified according to International League Against Epilepsy (ILAE) classification (2015). Outcome measures were SE duration, antiepileptic drugs (AEDs) administered, mortality at 12 months, Engel scale, and modified Rankin scale (m-RS) at 6 months. A second cohort included those consecutive patients discharged with a true stroke relapse in the same considered time span. Clinical characteristics of these two cohorts were compared using Mann-Whitney test or Student t-test (Confidence Interval (C.I.) 95%, p < 0.05) for continuous variable and Fisher exact test or Pearson-Chi test for dichotomic variables (p < 0.05). Survival rates were calculated, and a Log-Rank test was performed to evaluate differences in survival distribution. Only in the group with SE, m-RS at 6 months and recurrence of SE were also evaluated.

RESULTS

Eleven patients were discharged with a diagnosis of SE mimicking stroke and 65 patients with stroke relapse. Temporal lobe localization was significantly more represented in group with SE (p = 0.036) while there was no difference regarding age, sex, and National Institutes of Health Stroke Scale (NIHSS). The m-RS was significantly higher in patients with hemorrhage relapse, mainly due to the high incidence of amyloid angiopathy in this subgroup. Status epilepticus recurred in 36.4% of patients, presenting with the same clinical features, and most patients (62.5%) achieved a good seizure control at 6 months (Engel scale = 1). A difference in mortality at 12 months (all cause considered) appeared only when distinguishing strokes between ischemic and hemorrhagic (Chi-Square: 10.711, p < 0.005).

DISCUSSION AND CONCLUSION

Status epilepticus is not infrequent in patients with previous stroke and may present with negative neurological symptoms, thus mimicking a stroke recurrence. EEG should be considered as a potential diagnostic tool in the acute stroke setting, at least in patients with previous stroke. This article is part of the Special Issue "Seizures & Stroke".

Early seizures after ischemic stroke: focus on thrombolysis

INTRODUCTION

Stroke is a significant underlying cause of epilepsy. Seizures due to ischemic stroke (IS) are generally categorized into early seizures (ESs) and late seizures (LSs). Seizures in thrombolysis situations may raise the possibility of other etiology than IS.

AIM

We overtook a systematic review focusing on the pathogenesis, prevalence, risk factors, detection, management, and clinical outcome of ESs in IS and in stroke/thrombolysis situations. We also collected articles focusing on the association of recombinant tissue-type plasminogen activator (rt-PA) treatment and epileptic seizures.

RESULTS

We have identified 37 studies with 36,775 participants. ES rate was 3.8% overall in patients with IS with geographical differences. Cortical involvement, severe stroke, hemorrhagic transformation, age (<65 years), large lesion, and atrial fibrillation were the most important risk factors. Sixty-one percent of ESs were partial and 39% were general. Status epilepticus (SE) occurred in 16.3%. 73.6% had an onset within 24 h and 40% may present at the onset of stroke syndrome. Based on EEG findings seizure-like activity could be detected only in approximately 18% of ES patients. MRI diffusion-weighted imaging and multimodal brain imaging may help in the differentiation of ischemia vs. seizure. There are no specific recommendations with regard to the treatment of ES.

CONCLUSION

ESs are rare complications of acute stroke with substantial burden. A significant proportion can be presented at the onset of stroke requiring an extensive diagnostic workup.

Intravenous thrombolysis for suspected ischemic stroke with seizure at onset

OBJECTIVE

Seizure at onset (SaO) has been considered a relative contraindication for intravenous thrombolysis (IVT) in patients with acute ischemic stroke, although this appraisal is not evidence based. Here, we investigated the prognostic significance of SaO in patients treated with IVT for suspected ischemic stroke.

METHODS

In this multicenter, IVT-registry-based study we assessed the association between SaO and symptomatic intracranial hemorrhage (sICH, European Cooperative Acute Stroke Study II definition), 3-month mortality, and 3-month functional outcome on the modified Rankin Scale (mRS) using unadjusted and adjusted logistic regression, coarsened exact matching, and inverse probability weighted analyses.

RESULTS

Among 10,074 IVT-treated patients, 146 (1.5%) had SaO. SaO patients had significantly higher National Institutes of Health Stroke Scale score and glucose on admission, and more often female sex, prior stroke, and prior functional dependence than non-SaO patients. In unadjusted analysis, they had generally less favorable outcomes. After controlling for confounders in adjusted, matched, and weighted analyses, all associations between SaO and any of the outcomes disappeared, including sICH (odds ratio [OR]_unadjusted = 1.53 [95% confidence interval (CI) = 0.74-3.14], OR_adjusted = 0.52 [95% CI = 0.13-2.16], OR_matched = 0.68 [95% CI = 0.15-3.03], OR_weighted = 0.95 [95% CI = 0.39-2.32]), mortality (OR_unadjusted = 1.49 [95% CI = 1.00-2.24], OR_adjusted = 0.98 [95% CI = 0.5-1.92], OR_matched = 1.13 [95% CI = 0.55-2.33], OR_weighted = 1.17 [95% CI = 0.73-1.88]), and functional outcome (mRS ≥ 3/ordinal mRS: OR_unadjusted = 1.33 [95% CI = 0.96-1.84]/1.35 [95% CI = 1.01-1.81], OR_adjusted = 0.78 [95% CI = 0.45-1.32]/0.78 [95% CI = 0.52-1.16], OR_matched = 0.75 [95% CI = 0.43-1.32]/0.45 [95% CI = 0.10-2.06], OR_weighted = 0.87 [95% CI = 0.57-1.34]/1.00 [95% CI = 0.66-1.52]). These results were consistent regardless of whether patients had an eventual diagnosis of ischemic stroke (89/146) or stroke mimic (57/146 SaO patients).

INTERPRETATION

SaO was not an independent predictor of poor prognosis. Withholding IVT from patients with assumed ischemic stroke presenting with SaO seems unjustified. ANN NEUROL 2019;86:770-779.

The Yield of Multimodal Computed Tomography among Emergency Department Patients with Suspected Large Vessel Occlusion Stroke

OBJECTIVES

Endovascular therapy (EVT) improves outcomes for appropriately selected acute ischemic stroke patients. Guidelines suggest rapid acquisition of noninvasive vascular imaging to screen suspected ischemic stroke patients for large vessel occlusion (LVO) and candidacy for EVT. We sought to quantify the yield of an LVO stroke screening process in an undifferentiated emergency department (ED) suspected stroke population as well as identify predictors of successful EVT.

METHODS

We identified a cohort of consecutive ED patients who received CT angiography and brain perfusion (CTA/P) imaging to determine candidacy for EVT during 2016. In keeping with the guidelines at that time, hospital protocol directed physicians to obtain CTA/P studies if time from the onset of symptoms was less than or equal to 6 hours, and the National Institute of Health Stroke Scale (NIHSS) more than or equal to 6 or if recommended by the consulting stroke neurologist. Final discharge diagnoses, EVT attempts, and successful reperfusion (TICI 2b or better) were recorded. Yield of CTA/P was compared among patients based on NIHSS and duration of symptoms.

RESULTS

Over a 12-month period, 406 suspected stroke patients were screened with CTA/P; 273 (67%) received a final diagnosis of ischemic stroke. Among cases screened, 53 (13%) underwent attempted EVT; 35 (9%) achieved successful reperfusion. Only 1 of 113 (1%) patients with an NIHSS less than 6 was successfully treated with EVT compared to 34 of 285 (12%) with higher NIHSS (p = 0.001). The probability of successful EVT declined with increasing symptom duration (p = 0.009 for trend). In multivariable analysis, NIHSS more than or equal to 6 was associated with successful EVT (odds ratio [OR] 4.0 [1.6 to 9.9]) but presentation within 6 hours of onset was not (OR 2.3 [0.8 to 6.7]).

CONCLUSIONS

EVT candidates were common among suspected stroke patients screened with CTA/P in the ED, however, patients with NIHSS less than 6 rarely received successful EVT.

Prehospital stroke scales as screening tools for early identification of stroke and transient ischemic attack

BACKGROUND

Rapid and accurate detection of stroke by paramedics or other emergency clinicians at the time of first contact is crucial for timely initiation of appropriate treatment. Several stroke recognition scales have been developed to support the initial triage. However, their accuracy remains uncertain and there is no agreement which of the scales perform better.

OBJECTIVES

To systematically identify and review the evidence pertaining to the test accuracy of validated stroke recognition scales, as used in a prehospital or emergency room (ER) setting to screen people suspected of having stroke.

SEARCH METHODS

We searched CENTRAL, MEDLINE (Ovid), Embase (Ovid) and the Science Citation Index to 30 January 2018. We handsearched the reference lists of all included studies and other relevant publications and contacted experts in the field to identify additional studies or unpublished data.

SELECTION CRITERIA

We included studies evaluating the accuracy of stroke recognition scales used in a prehospital or ER setting to identify stroke and transient Ischemic attack (TIA) in people suspected of stroke. The scales had to be applied to actual people and the results compared to a final diagnosis of stroke or TIA. We excluded studies that applied scales to patient records; enrolled only screen-positive participants and without complete 2 × 2 data.

DATA COLLECTION AND ANALYSIS

Two review authors independently conducted a two-stage screening of all publications identified by the searches, extracted data and assessed the methodologic quality of the included studies using a tailored version of QUADAS-2. A third review author acted as an arbiter. We recalculated study-level sensitivity and specificity with 95% confidence intervals (CI), and presented them in forest plots and in the receiver operating characteristics (ROC) space. When a sufficient number of studies reported the accuracy of the test in the same setting (prehospital or ER) and the level of heterogeneity was relatively low, we pooled the results using the bivariate random-effects model. We plotted the results in the summary ROC (SROC) space presenting an estimate point (mean sensitivity and specificity) with 95% CI and prediction regions. Because of the small number of studies, we did not conduct meta-regression to investigate between-study heterogeneity and the relative accuracy of the scales. Instead, we summarized the results in tables and diagrams, and presented our findings narratively.

MAIN RESULTS

We selected 23 studies for inclusion (22 journal articles and one conference abstract). We evaluated the following scales: Cincinnati Prehospital Stroke Scale (CPSS; 11 studies), Recognition of Stroke in the Emergency Room (ROSIER; eight studies), Face Arm Speech Time (FAST; five studies), Los Angeles Prehospital Stroke Scale (LAPSS; five studies), Melbourne Ambulance Stroke Scale (MASS; three studies), Ontario Prehospital Stroke Screening Tool (OPSST; one study), Medic Prehospital Assessment for Code Stroke (MedPACS; one study) and PreHospital Ambulance Stroke Test (PreHAST; one study). Nine studies compared the accuracy of two or more scales. We considered 12 studies at high risk of bias and one with applicability concerns in the patient selection domain; 14 at unclear risk of bias and one with applicability concerns in the reference standard domain; and the risk of bias in the flow and timing domain was high in one study and unclear in another 16.We pooled the results from five studies evaluating ROSIER in the ER and five studies evaluating LAPSS in a prehospital setting. The studies included in the meta-analysis of ROSIER were of relatively good methodologic quality and produced a summary sensitivity of 0.88 (95% CI 0.84 to 0.91), with the prediction interval ranging from approximately 0.75 to 0.95. This means that the test will miss on average 12% of people with stroke/TIA which, depending on the circumstances, could range from 5% to 25%. We could not obtain a reliable summary estimate of specificity due to extreme heterogeneity in study-level results. The summary sensitivity of LAPSS was 0.83 (95% CI 0.75 to 0.89) and summary specificity 0.93 (95% CI 0.88 to 0.96). However, we were uncertain in the validity of these results as four of the studies were at high and one at uncertain risk of bias. We did not report summary estimates for the rest of the scales, as the number of studies per test per setting was small, the risk of bias was high or uncertain, the results were highly heterogenous, or a combination of these.Studies comparing two or more scales in the same participants reported that ROSIER and FAST had similar accuracy when used in the ER. In the field, CPSS was more sensitive than MedPACS and LAPSS, but had similar sensitivity to that of MASS; and MASS was more sensitive than LAPSS. In contrast, MASS, ROSIER and MedPACS were more specific than CPSS; and the difference in the specificities of MASS and LAPSS was not statistically significant.

AUTHORS' CONCLUSIONS

In the field, CPSS had consistently the highest sensitivity and, therefore, should be preferred to other scales. Further evidence is needed to determine its absolute accuracy and whether alternatives scales, such as MASS and ROSIER, which might have comparable sensitivity but higher specificity, should be used instead, to achieve better overall accuracy. In the ER, ROSIER should be the test of choice, as it was evaluated in more studies than FAST and showed consistently high sensitivity. In a cohort of 100 people of whom 62 have stroke/TIA, the test will miss on average seven people with stroke/TIA (ranging from three to 16). We were unable to obtain an estimate of its summary specificity. Because of the small number of studies per test per setting, high risk of bias, substantial differences in study characteristics and large between-study heterogeneity, these findings should be treated as provisional hypotheses that need further verification in better-designed studies.

Seizure in code stroke: Stroke mimic and initial manifestation of stroke

BACKGROUND

Although seizure is one of the common causes of stroke mimics and can be an initial manifestation of acute stroke, accurate diagnosis of seizure during acute stroke management is frequently difficult. The objective of this study was to analyze the frequency, characteristics and results of neuroimaging including CT perfusion in patients with seizures manifesting initially as stroke-like symptoms.

METHODS

We retrospectively reviewed the medical records of patients who were treated with code stroke alarming system. We studied the frequency and characteristics of patients who were finally diagnosed with seizures and further correlated their clinical features with the results of neuroimaging including CT perfusion.

RESULTS

Among the 4673 patients who were treated with code stroke alarming system, seizure was the third most frequent diagnosis (188 patients, 4.0%) among the causes of stroke mimics including 27 patients who manifested seizure as an initial manifestation of acute stroke. CT perfusion showed perfusion changes in more than 25% of them (49 of 188 patients, 26.1%). Thrombolysis was not performed in six patients who presented with seizure as an initial presentation of stroke for delayed diagnosis while one patient underwent thrombolysis for misdiagnosis of seizure.

CONCLUSIONS

Seizure is a frequent final diagnosis in acute stroke management. However, careful interpretation of clinical features and results of perfusion imaging is necessary to avoid unnecessary thrombolysis in patients with seizure as a stroke mimic and thrombolysis failure due to delayed diagnosis of seizure as an initial manifestation of stroke.

Enhancing Value of MRI: A Call for Action

As national healthcare spending has spiraled out of control, payment reform that moves from volume to value-based payment has been introduced as a practical solution. Under alternative value-based payment models, physicians and clinical teams must deliver the best care possible at a lower cost. Medical imaging has changed the way we diagnose disease, evaluate severity, assess treatment effects, and provide biological insights for the pathophysiology of many diseases. Over the past 50 years, imaging techniques have become increasingly advanced-from X-ray to computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), and multi-modal imaging. Advanced imaging such as MRI has given clinicians remarkable insights into medical conditions and saved innumerable lives. Under the value proposition, however, we must ask if each imaging study changes treatment decisions, improves patient outcomes, and is cost-effective. Imaging research has been focused on developing new technologies and clinical applications to assess diagnostic accuracy. What is needed is the higher-level technology assessment. In this article we review why we need to demonstrate the value of MRI, how we define value, what strategies can enhance MR value through partnership with various stakeholders, and how imaging scientists can contribute to healthcare delivery in the future. Level of Evidence: 5 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;49:e40-e48.

Evaluation of a score for the prehospital distinction between cerebrovascular disease and stroke mimic patients

Background

Patients with a sudden onset of focal neurological deficits consistent with stroke, who turn out to have alternative conditions, have been labeled stroke mimics.

Aims

We assessed a recently validated telemedicine-based stroke mimic score (TeleStroke mimic score; TM-score) and individual patient characteristics with regard to its discriminative value between cerebrovascular disease and stroke mimic patients in the in-person, pre-hospital setting.

Methods

We evaluated patients cared for in a mobile stroke unit in Berlin, Germany. We investigated whether the TM-score (comprising six parameters), Face Arm Speech Time test, and individual patient characteristics were able to differentiate cerebrovascular disease from stroke mimic patients.

Results

We included 423 patients (299 (70.7%) cerebrovascular disease and 124 (29.3%) stroke mimic) in the final analysis. A TM-score > 30 indicated a high probability of a cerebrovascular disease and a score ≤15 of a stroke mimic. The TM-score performed well to identify stroke mimics (area under the curve of 0.74 under receiver-operating characteristic curve analysis). The cerebrovascular disease patients were older (74.8 vs. 69.8 years, p = 0.001), had more often severe strokes (NIHSS > 14 25.8% vs. 11.3%, p = 0.001), presented more often with weakness of the face (70.9% vs. 42.7%, p = 0.001) or arm (60.9% vs. 33.9%, p = 0.001), dysarthria (59.5% vs. 40.3%, p < 0.001), history of atrial fibrillation (38.1% vs. 21.0%, p = 0.001), arterial hypertension (78.9% vs. 53.2%, p < 0.001), and less often with seizure (0.7% vs. 21.0%, p < 0.001).

Conclusions

The TM-score and certain patient characteristics can help paramedics and emergency physicians in the field to identify stroke mimic patients and select the most appropriate hospital destination.

Functional Somatic Symptoms Across Cultures: Perceptual and Health Care Issues

Functional neurological disorders are conceptualized as patterns of neurological symptoms that cannot be attributed to a clear organic etiology. The study by Wilkins et al. in this issue of Psychosomatic Medicine reveals that 8.2% of patients who were initially presented with suspected stroke were later diagnosed with functional disorders, i.e., "functional stroke mimics." However, the percentage of functional stroke mimics varied substantially with patients' nationality, age, and sex. In this editorial comment, we discuss potential reasons for the intercultural variation of the frequency of functional stroke mimics.The current models of symptom perception, in which symptom perception is guided by top-down processes of the central nervous system, are helpful in explaining the intercultural variation of functional symptoms. According to these models, cultural beliefs, previous illnesses, and stressful life situations influence patients' expectations, sensory input, and finally the perception of somatic symptoms. In addition, differences in insurance status, health literacy, and health care experiences are strong predictors of health care use in patients who experience somatic symptoms.This article provides a conceptual model that integrates sociocultural factors with symptom perception and health care use relevant to the different rates of functional somatic symptoms in emergency departments across nationalities. Considering these factors, future attempts to improve care for patients with functional disorders should enhance access to effective treatment for all patient groups, empower patients through education and early participation in the treatment process, and foster interdisciplinary collaboration among specialists from somatic and mental health disciplines.

Functional Stroke Mimics: Incidence and Characteristics at a Primary Stroke Center in the Middle East

OBJECTIVE

Approximately 30% of individuals who initially present with stroke are found to be stroke mimics (SM), with functional/psychological SM (FSM) accounting for up to 6.4% of all stroke presentations. Middle Eastern countries may have higher rates of somatization of emotional distress. The aim of this study was to evaluate the incidence and characteristics of FSM at a large general hospital in the Middle East.

METHODS

All patients presenting with an initial diagnosis of stroke from June 2015 to September 2016 were eligible for this study. Clinical and sociodemographic data were obtained from the hospital's stroke database. All SM and strokes were diagnosed by Joint Commission International-certified stroke program neurologists. SM was defined as any discharge diagnosis (other than acute stroke) for symptoms that prompted initial admission for suspected stroke. FSM were compared with medical stroke mimics (MSM) and strokes (ischemic, hemorrhagic, and transient ischemic attacks).

RESULTS

A total of 1961 patients were identified; 161 FSM (8.2%), 390 MSM (19.9%), and 1410 strokes (71.9%) (985 ischemic strokes, 196 transient ischemic attacks, 229 intracerebral hemorrhages). Admission with FSM was related to patients' nationality, with the highest frequency in Arabic (15.6%) and African (16.8%) patients. FSM patients were younger, more often female, and had fewer cardiovascular risk factors except for smoking compared with the strokes. FSM patients presented with more left-sided weakness and had more magnetic resonance imagings than the stroke and MSM groups. A total of 9.9% of FSM patients received thrombolysis versus only 0.5% of the MSM and 16.4% of ischemic strokes.

CONCLUSIONS

FSM frequencies varied by nationality, with Arab and African nationals being twice as prevalent. Stress, vulnerable status as expats, sociopolitical instability, and exposure to trauma are proposed as potential factors contributing to FSM.

When migraine mimics stroke: A systematic review

BACKGROUND

Migraine with aura may mimic an acute ischemic stroke, so that an improper administration of thrombolytic treatment can expose migrainous patients to severe adverse effects.

METHODS

This systematic review quantifies the relevance of migraine with aura among stroke mimics, checking for thrombolysis' safety in these patients. We reviewed the literature after 1995, distinguishing from studies dealing with stroke mimics treated with systemic thrombolysis and those who were not treated with systemic thrombolysis.

RESULTS

Migraine with aura is responsible for 1.79% (CI 95% 0.82-3.79%) of all the emergency Stroke Unit evaluations and it represents 12.24% (CI 95% 6.34-22.31%) of stroke mimics in the group not treated with systemic thrombolysis. 6.65% (CI 95% 4.32-9.78%) of systemic thrombolysis administrations are performed in patients without an acute ischemic stroke. Migraine with aura is responsible for 17.91% of these (CI 95% 13.29-23.71%). The reported rate of adverse events seems extremely low (0.01%).

CONCLUSION

Migraine with aura is the third most common stroke mimic, following seizures and psychiatric disorders; it is responsible for about 18% of all improper thrombolytic treatments. Despite the absence of strong supporting data, thrombolysis in migraine with aura seems to be a procedure with an extremely low risk of adverse events.

[Factors influencing the detection of ischemic stroke in neuroimaging]

AIM

To determine the detectability of foci of acute ischemic stroke (AI) using neuroimaging methods depending on the localization, timing and severity of stroke.

MATERIAL AND METHODS

A retrospective evaluation of 100 case histories of patients hospitalized for ischemic stroke (IS) with determination of the timing of neuroimaging study, fibrinogen level, glucose, INR, NIHSS scores on admission to the hospital, assessment of stroke localization (hemispheric or brainstem), the severity of atherosclerosis of the brachiocephalic arteries (BCA) and presence of atrial fibrillation (AF) was performed. During the stay in the hospital, 54 patients were re-examined to clarify the diagnosis. All patients were divided into 2 groups: patients with the focus of AI revealed on primary neuroimaging study (group 1) and patients with the focus of AI at repeated neuroimaging or patients without lesions on CT or MRI (group 2).

RESULTS

Stem strokes were dominated in group 2. An increase in glucose above 10 mmol/l was more often detected in group 1 (p<0.05). AF was detected in 13 patients of group 1 and 9 of group 2. NIHSS <10 values were detected in 8 patients of group 1 and 3 patients of group 2 (p<0.05). An occlusive BCA lesion was found only in patients of group 1(n=4).

CONCLUSION

Cases of AI not detected by CT/MRI on admission to the hospital are more common in women, have stem localization, characterized by low values of NIHSS and lower glucose levels on admission to the hospital.

Stroke mimics in patients with clinical signs of stroke

Background:

Stroke mimic is a major diagnostic challenge and may be difficult to distinguish from real strokes. The aim of this study was to evaluate the relative frequency of stroke mimics in patients with clinical signs of stroke.

Methods:

In this cross sectional-study, the medical records of 1985 patients with stroke admitted to Poursina Hospital were enrolled using the census technique. Data collection tool was a checklist which include age, sex, imaging results (MRI and CT scan and primary and final diagnoses.

Results:

Of the 1985 patients, 295 (14.9%) were identified with brain stroke mimics. The mean age in the group of patients with mimics and real stroke were 66.5±16.4 years and 72.4±9.6 years, respectively. The highest number of stroke belonged to 61-80 years in stroke groups (68.8%) and mimics (58.3%), respectively. There was a significant correlation between age and early diagnosis of stroke or stroke mimic (P<0.0001). The highest frequency of stroke mimics was related to brain tumors (10.5%), hypoglycemia (9.2%) and toxic poisoning (8.5%).

Conclusion:

Due to the high number of stroke mimics, further attention is necessary to aid in differential diagnosis and clinical procedures in patients with stroke signs.

PreHospital Ambulance Stroke Test - pilot study of a novel stroke test

Background

There is a need for a prehospital stroke test that in addition to high sensitivity for stroke, also is able to communicate stroke severity similar to the National Institute of Health Stroke Scale (NIHSS).

Methods

The PreHospital Ambulance Stroke Test (PreHAST), an eight item test based on NIHSS, which scores stroke severity from 0–19 points, was designed and adapted for the ambulance services. In the pilot study the ambulance nurses used PreHAST to assess patients with suspected stroke in the prehospital setting. Regardless of the results after PreHAST testing the patients were triaged with a provisional stroke diagnosis. The PreHAST scores were compared with the final diagnosis and the ability to differentiate stroke and transient ischemic attacks (TIA) with ongoing symptoms at evaluation from non-stroke patients was analysed.

Results

69 patients were included in the study, 26 had stroke/TIA and 43 other diagnoses. All stroke/TIA patients were identified by PreHAST (sensitivity 100% (95% CI; 87-100%)). The specificity increased with higher PreHAST scores and the discriminative capacity for PreHAST for different cut off values showed an area under the curve of 0.77 (95%CI; 0.66-0.88) in the receiver operating characteristic (ROC) analysis.

Discussion

PreHAST is designed for high sensitivity, screening for a broad range of stroke symptoms including most key components of NIHSS. The promising sensitivity between 87 and 100% in our study has to be confirmed in a larger study also including multiple centres. Higher PreHAST scores implied more typical patterns of stroke and accordingly the proportion of stroke mimics decrease with higher scores. However, also stroke mimics with epilepsy/seizure and patients with deficit after prior stroke could show higher PreHAST scores. Other prehospital stroke tests that evaluate stroke severity have been designed with the main purpose to screen for large vessel occlusion. The advantage of PreHAST is the dual purpose not only to evaluate stroke severity but also to screen for stroke in general.

Conclusions

PreHAST is a new screening test of stroke adapted for ambulance services that in addition to high sensitivity for stroke, provides a grading system with increasing specificity with higher scores.

Variables That Best Differentiate In-Patient Acute Stroke from Stroke-Mimics with Acute Neurological Deficits

Introduction. Strokes and stroke-mimics have been extensively studied in the emergency department setting. Although in-hospital strokes are less studied in comparison to strokes in the emergency department, they are a source of significant direct and indirect costs. Differentiating in-hospital strokes from stroke-mimics is important. Thus, our study aimed to identify variables that can differentiate in-hospital strokes from stroke-mimics. Methods. We present here a retrospective analysis of 93 patients over a one-year period (2009 to 2010), who were evaluated for a concern of in-hospital strokes. Results. About two-thirds (57) of these patients were determined to have a stroke, and the remaining (36) were stroke-mimics. Patients with in-hospital strokes were more likely to be obese (p = 0.03), have been admitted to the cardiology service (p = 0.01), have atrial fibrillation (p = 0.03), have a weak hand or hemiparesis (p = 0.03), and have a prior history of stroke (p = 0.05), whereas, when the consults were called for “altered mental status” but no other deficits (p < 0.0001), it is likely a stroke-mimic. Conclusion. This study demonstrates that in-hospital strokes are a common occurrence, and knowing the variables can aid in their timely diagnosis and treatment.