A case-control comparison of acute-phase peripheral blood gene expression in participants diagnosed with minor ischaemic stroke or stroke mimics.

BACKGROUND: Past studies suggest that there are changes in peripheral blood cell gene expression in response to ischaemic stroke; however, the specific changes which occur during the acute phase are poorly characterised. The current study aimed to identify peripheral blood cell genes specifically associated with the early response to ischaemic stroke using whole blood samples collected from participants diagnosed with ischaemic stroke (n = 29) or stroke mimics (n = 27) following emergency presentation to hospital. Long non-coding RNA (lncRNA), mRNA and micro-RNA (miRNA) abundance was measured by RNA-seq, and the consensusDE package was used to identify genes which were differentially expressed between groups. A sensitivity analysis excluding two participants with metastatic disease was also conducted. RESULTS: The mean time from symptom onset to blood collection was 2.6 h. Most strokes were mild (median NIH stroke scale score 2.0). Ten mRNAs (all down-regulated in samples provided by patients experiencing ischaemic stroke) and 30 miRNAs (14 over-expressed and 16 under-expressed in participants with ischaemic stroke) were significantly different between groups in the whole cohort and sensitivity analyses. No significant over-representation of gene ontology categories by the differentially expressed genes was observed. Random forest analysis suggested a panel of differentially expressed genes (ADGRG7 and miRNAs 96, 532, 6766, 6798 and 6804) as potential ischaemic stroke biomarkers, although modelling analyses demonstrated that these genes had poor diagnostic performance. CONCLUSIONS: This study provides evidence suggesting that the early response to minor ischaemic stroke is predominantly reflected by changes in the expression of miRNAs in peripheral blood cells. Further work in independent cohorts particularly in patients with more severe stroke is needed to validate these findings and investigate their clinical relevance.

Thrombotic thrombocytopenic purpura presenting as stroke mimics with normal diffusion-weighted MRI.

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare and fatal thrombotic microangiopathy-based hematologic disease. Stroke has been reported as atypical neurological manifestations of TTP in some cases. CASE PRESENTATION: A 65-year-old male presented with typical acute ischemic stroke symptoms including sudden-onset dysarthria, right-sided facial paralysis and hemiplegia. However, his CT and MRI scans were negative without showing any new ischemic lesions. He was diagnosed with TTP with severe thrombocytopenia, mild anemia, increased LDH, and low ADAMTS-13 activity. The symptoms and positive signs were rapidly resolved after administrating the plasma exchange therapy. CONCLUSION: Clinicians should consider the possibility of TTP when a patient presents with acute stroke-like symptoms and thrombocytopenia, especially in an emergency room, either with or without new stroke lesions on the brain CT and MRI.

Characteristics and predictors of stroke mimics in young patients in the norwegian tenecteplase stroke trial (NOR-TEST).

BACKGROUND: Several studies have shown that stroke mimics occur more often among young patients. Our aims were to identify the common mimics in young patients under the age of 60 years who received thrombolysis, to analyze the risk of hemorrhage after treatment with thrombolysis, and to identify risk factors and clinical parameters that might identify mimics in this group. METHODS: Norwegian Tenecteplase Stroke Trial was a phase-3 trial investigating safety and efficacy of tenecteplase vs. alteplase in patients with acute ischemic stroke. Patients diagnosed with either acute cerebral ischemia or transient ischemic attack were categorized as stroke group, and patients with any diagnosis other than ischemic stroke or transient ischemic attack as mimics group. Patients were grouped post-hoc into young (< 60 years) and old (≥ 60 years). Logistic regression analyses were performed with mimics vs. stroke as dependent variable to identify predictors of mimics. RESULTS: Of the 1091 patients included in the trial, 211 patients (19.3%) were under the age of 60 years. Out of the 1091 patients, 434 (39.8%) were female, median age 77 years (18-99 years), and median NIHSS was 4. Sixty-nine patients (32.7%) out of the 211 patients under the age of 60 were diagnosed as mimic. Mimics were significantly more frequent among the young (OR = 3.3, 32.7% vs. 12.8%, p = < 0.001). The most frequent mimics diagnoses among patients under 60 years of age were migraine (11.8%), no definite diagnosis (11.4%) and peripheral vertigo (3.3%). Mimics were independently associated with age < 50 years (OR = 4.97, p = < 0.001), not currently working/studying (OR = 3.38, p = 0.002) and not having aphasia on admission (OR = 2.95, p = 0.025). None of the mimics under the age of 60 years had symptomatic or asymptomatic intracerebral hemorrhage as a complication to thrombolysis. CONCLUSION: We found significantly more mimics in the young, of which migraine was the most predominant diagnosis. Thrombolysis with alteplase or tenecteplase did not cause ICH in any mimics under 60 years.

Thrombolysis in Stroke Mimics: Comprehensive Stroke Centers vs Telestroke Sites.

BACKGROUND: Hyperacute treatment of acute stroke may lead to thrombolysis in stroke mimics (SM). Our aim was to determine the frequency of thrombolysis in SM in primary stroke centers (PSC) dependent on telestroke versus comprehensive stroke centers (CSC). METHOD: Retrospective review of prospectively collected data from the Quality improvement and Clinical Research (QuICR) registry, the Discharge Abstract Database (DAD), and The National Ambulatory Care Reporting System (NACRS) of consecutive patients treated with intravenous thrombolysis for acute ischemic stroke in Alberta (Canada) from April 2016 to March 2021. RESULT: A total of 2471 patients who received thrombolysis were included. Linking the QuICR registry to DAD 169 (6.83%) patients were identified as SM; however, on our review of the records, only 112 (4.53%) were actual SM. SMs were younger with a mean age of 61.66 (±16.15) vs 71.08 (±14.55) in stroke. National Institute of Health Stroke Scale was higher in stroke with a median (IQR) of 10 (5-17) vs 7 (5-10) in SM. Only one patient (0.89 %) in SM groups had a small parenchymal hemorrhage versus 155 (6.57%) stroke patients had a parenchymal hemorrhage. There was no death among patients of thrombolysed SM during hospitalization versus 276 (11.69%) in stroke. There was no significant difference in the rate of SM among thrombolysed patients between PSC 27 (5.36%) versus CSC 85 (4.3%) (P = 0.312). The most responsible diagnosis of SM was migraine/migraine equivalent, functional disorder, seizure, and delirium. CONCLUSION: The diagnosis of SM may not always be correct when the information is extracted from databases. The rate of thrombolysis in SM via telestroke is similar to treatment in person at CSC.

A case of spinal epidural lipomatosis presenting as a stroke mimic.

Here we present the case of a patient with right upper extremity and right lower extremity weakness of a three-day duration, which triggered a stroke evaluation. Ultimately, the diagnosis of spinal epidural lipomatosis (SEL) was made. Non-stroke diagnoses that present with stroke-like symptoms are referred to in the medical literature as stroke mimics. Such cases present with neurological deficits that imitate acute ischemic stroke. The frequency of such presentations occurs in up to 30% of initially suspected stroke. This case illustrates that SEL can present as a stroke mimic. To our knowledge, this is the first description of a presentation in the medical literature of SEL as a stroke mimic.

Spontaneous Spinal Epidural Hematoma Mimicking Stroke and Its Outcome post Intravenous Thrombolysis.

BACKGROUND AND PURPOSE: Spontaneous spinal epidural hematoma (SSEH) is a rare neurological emergency. Its presentation, depending on location of hematoma, could mimic stroke. While intravenous thrombolysis (IVT) is recommended to commence as early as possible in case of acute ischemic stroke, it is likely that it could be given to SSEH patients. We aimed to examine the prevalence, outcome, and prognosis of such patients. METHODS: We have retrospectively screened all patients given IVT from January 2008 to March 2021 admitted to United Christian Hospital, a tertiary hospital in Hong Kong. We reviewed the final diagnosis of all patients and included cases diagnosed with SSEH. Their clinical and radiological features, treatment, and outcome were analyzed. We further performed a literature review to search for all cases with SSEH given IVT and review their clinical features and outcome. RESULTS: Out of a total of 940 patients over the 12-year span, 2 patients were diagnosed with SSEH, accounting for 0.21% of cases. From our literature search, to date, there are only 10 cases that had been reported from 5 case reports where IVT was given to SSEH patients. Of the 12 cases, all presented with hemiparesis and 9 with pain. Of those with neck pain, 3 with initial computed tomography angiogram done showed SSEH which was missed initially. Eight were treated surgically and 4 conservatively. All recovered with no major disability. CONCLUSIONS: Though a rare disease, awareness toward SSEH presenting as stroke mimic should be raised.

Stroke unit demand in Norway - present and future estimates.

BACKGROUND: All stroke patients should receive timely admission to a stroke unit (SU). Consequently, most patients with suspected strokes - including stroke mimics (SM) are admitted. The aim of this study was to estimate the current total demand for SU bed capacity today and give estimates for future (2020-2040) demand. METHODS: Time trend estimates for stroke incidence and time constant estimates for length of stay (LOS) were estimated from the Norwegian Patient Registry (2010-2015). Incidence and LOS models for SMs were based on data from Haukeland University Hospital (2008-2017) and Akershus University Hospital (2020), respectively. The incidence and LOS models were combined with scenarios from Statistic Norway's population predictions to estimate SU demands for each health region. A telephone survey collected data on the number of currently available SU beds. RESULTS: In 2020, 361 SU beds are available, while demand was estimated to 302. The models predict a reduction in stroke incidence, which offsets projected demographic shifts. Still, the estimated demand for 2040 rose to 316, due to an increase in SMs. A variation of this reference scenario, where stroke incidence was frozen at the 2020-level, gave a 2040-demand of 480 beds. CONCLUSIONS: While the stroke incidence is likely to continue to fall, this appears to be balanced by an increase in SMs. An important uncertainty is how long the trend of decreasing stroke incidence can be expected to continue. Since the most important uncertainty factors point toward a potential increase, which may be as large as 50%, we would recommend that the health authorities plan for a potential increase in the demand for SU bed capacity.

Clinical Differences Between Stroke and Stroke Mimics in Code Stroke Patients.

BACKGROUND: The code stroke system is designed to identify stroke patients who may benefit from reperfusion therapy. It is essential for emergency physicians to rapidly distinguish true strokes from stroke mimics to activate code stroke. This study aimed to investigate the clinical and neurological characteristics that can be used to differentiate between stroke and stroke mimics in the emergency department (ED). METHODS: We conducted a retrospective observational study of code stroke patients in the ED from January to December 2019. The baseline characteristics and the clinical and neurological features of stroke mimics were compared with those of strokes. RESULTS: A total of 409 code stroke patients presented to the ED, and 125 (31%) were diagnosed with stroke mimics. The common stroke mimics were seizures (21.7%), drug toxicity (12.0%), metabolic disorders (11.2%), brain tumors (8.8%), and peripheral vertigo (7.2%). The independent predictors of stroke mimics were psychiatric disorders, dizziness, altered mental status, and seizure-like movements, while current smoking, elevated systolic blood pressure, atrial fibrillation on the initial electrocardiogram, hemiparesis as a symptom, and facial palsy as a sign suggested a stroke. In addition, the likelihood of a stroke in code stroke patients tended to increase as the number of accompanying deficits increased from the following set of seven focal neurological deficits: hemiparesis (or upper limb monoparesis), unilateral limb sensory change, facial palsy, dysarthria, aphasia (or neglect), visual field defect, and oculomotor disorder (P < 0.001). CONCLUSION: Some clinical and neurological characteristics have been identified to help differentiate stroke mimics from true stroke. In particular, the likelihood of stroke tended to increase as the number of accompanying focal neurological deficits increased.

The importance of CT perfusion for diagnosis and treatment of ischemic stroke in anterior circulation.

Computed tomography perfusion (CTP) is a functional examination of brain tissue that characterises the state of cerebral perfusion and provides information about the current status of the circulation. CTP can improve diagnostic accuracy of ischemic stroke. Published studies showed that perfusion imaging improves the prognosis of patients with acute ischemic stroke in anterior circulation and allows patients to be referred for treatment outside the time window for administration of intravenous thrombolysis (IVT) or mechanical thrombectomy (MT). In this review we discuss technical aspects of CTP, clinical significance of CTP in anterior circulation stroke (ACS) and its role in diagnostics of stroke mimics.

Predictors of perfusion computed tomography alterations in stroke mimics attended as stroke code.

BACKGROUND AND PURPOSE: Stroke mimics (SMs) account for a significant number of patients attended as stroke code (SC) with an increasing number over the years. Recent studies show perfusion computed tomography (PCT) alterations in some SMs, especially in seizures. The objective of our study was to evaluate the clinical characteristics and PCT alterations in SMs attended as SC in order to identify potential predictors of PCT alterations in SMs. METHODS: A retrospective study was performed including all SC activations undergoing a multimodal CT study including non-enhanced computed tomography (CT), CT angiography and PCT, as part of our SC protocol, over 39 months. Patients with a final diagnosis of SM after complete diagnosis work-up were therefore selected. Clinical variables, diagnosis, PCT alteration patterns and type of map affected (Tmax or time to peak, cerebral blood flow and cerebral blood volume) were registered. RESULTS: Stroke mimics represent up to 16% (284/1761) of SCs with a complete multimodal study according to our series. Amongst SMs, 26% (74/284) showed PCT alterations. PCT abnormalities are more prevalent in seizures and status epilepticus and the main pattern is alteration of the time to peak map, of unilateral hemispheric distribution or of non-vascular territory. In our series, the independent predictors of alteration in PCT in SMs are aphasia, female sex and older age. CONCLUSIONS: Perfusion computed tomography alterations can be found amongst almost a third of SMs attended as SC, especially older women presenting with aphasia with a final diagnosis of epileptic seizures and status epilepticus.

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.

Contrast-induced encephalopathy mimicking total anterior circulation stroke: a case report and review of the literature.

INTRODUCTION: Contrast-induced encephalopathy is a rare and usually reversible entity due to the administration of iodinated contrast. Clinical manifestations include cortical blindness, encephalopathy, seizures and focal neurological deficits. METHODS: We report the case of a 56-year-old woman who developed global aphasia and right hemiplegia after a cerebral angiography performed for a subarachnoid haemorrhage. A prompt brain MRI resulted negative, while CT scan revealed left cerebral oedema with the cerebral sulci effacement. Complete recovery was observed in 10 days. DISCUSSION: Diagnosis of contrast-induced encephalopathy requires a temporal correlation between neurological dysfunction and administration of iodinated contrast. Usually, the symptomatology is transient with a full recovery within 48-72 h. The most common symptom is cortical blindness, while other symptoms have been rarely reported. Only 20 cases previously reported global aphasia and/or hemiplegia or mimed anterior circulation strokes. Prompt brain neuroimaging is essential in order to exclude an alternative diagnosis that requires a distinct therapeutic approach.

Criteria for Emergency Brain MRI During Stroke-Alert.

OBJECTIVES: Intravenous (IV) tissue plasminogen activator (tPA) should be given to patients with acute ischemic stroke (AIS) and avoided in stroke mimics (SM). Select use of emergency brain magnetic resonance imaging (eMRI-brain) in stroke-alerts aids diagnosis, but accepted utilization criteria for eMRI-brain do not currently exist. We developed criteria for eMRI-brain and report the yield of eMRI-brain in stroke-alert patients. MATERIALS AND METHODS: We developed three history-based criteria for performing eMRI-brain during stroke-alerts: (1) history of previous similar deficits, (2) change in consciousness at onset of symptoms, (3) symptom presentation consistent with migraine aura. We then performed a retrospective chart review of patients who presented as a stroke-alert over a 5-year period and determined how these criteria affected administration of IV tPA to AIS and SM patients. RESULTS: Among 3,512 stroke-alerts, 230 (8.1%) patients met our criteria for eMRI-brain exams: 217 (92.6%) had SM and 17 (7.4%) had AIS. Our IV tPA decision-making analysis showed that based on eMRI-brain IV tPA was less frequently administered to SM patients (PCC-0.841, p=0.036) with less failures to administer IV tPA to patients with AIS (PCC -0.907, p-value=0.013, Pearson correlation coefficient). No patients became ineligible for IV tPA due to MRI-related time delays. CONCLUSIONS: Our history based criteria for performing eMRI-brain during stroke-alerts show a high yield of stroke mimics. Selective eMRI-brain improves decision-making accuracy regarding IV tPA administration.

Uni-hemispheric hyperperfusion in the early postictal state: case report.

BACKGROUND: In the emergency setting of acute ischemic stroke, seizures have been reported in up to 4% of patients. In the absence of arterial occlusion, seizures may also cause abnormalities in CT perfusion in 78% of cases when the time window from onset to imaging is short. Both hyperperfusion and hypoperfusion in the postictal state have been described. Also, though rarely reported, postictal perfusion changes can be uni-hemispheric. In these cases, perfusion maps should be analyzed thoroughly, since perfusion reconstruction software relies heavily on a "normal" contralateral perfusion status. CASE PRESENTATION: A 39-year-old man was found on the ground with a minor head injury. On admission, his reactions were generally slow, but there were no other neurological symptoms, and blood pressure was low. The patient had a history of primary generalized epilepsy and admitted to dropping off his anti-epileptic medication. He was transferred to the radiological department for imaging but shortly before began to experience generalized onset tonic-clonic seizures which were brought under control by intravenous therapy with 10 mg diazepam. After approximately 15 min, a multimodal CT scan was performed, revealing marked changes in the perfusion of the brain hemispheres and posterior fossa, with sharp delimitation at the midline. Blood gas analysis was congruent with respiratory acidosis. Clinically, the patient remained awake without developing any new symptoms. He gradually recovered over the following 3 h and, against our medical recommendation, discharged himself from the hospital. CONCLUSIONS: To the authors' knowledge, this is the first report of an early postictal state describing sharply delimited uni-hemispheric hyperperfusion and hemispheric alteration of the cerebellum with an equally split rhombencephalon. Surprisingly, these changes were not associated with any focal neurological signs. To prevent misdiagnosis of perfusion alterations in seizures, radiologists and neurologists should be aware of the limitations of CT perfusion maps and software reconstructions. Novel use of CT perfusion reconstruction using peak enhancement helped in identifying the cerebral pathology.

Poststroke seizures as stroke mimics: Clinical assessment and management.

Epileptic seizures with postictal negative symptoms represent 20% of all suspected strokes and should be considered in the differential diagnosis of stroke in any patient presenting with an acute neurological deficit, mostly in absence of convulsions. Seizures may also occur at stroke onset, and the latter need to be promptly recognized in order to timely administer reperfusion therapies and reduce the risk of irreversible brain injury. Neuroimaging is essential in differentiating between postictal negative symptoms and deficits due to stroke. After the acute phase, poststroke seizures may worsen or cause the reappearance of neurological deficits and consciousness impairment; they can be also misinterpreted as stroke recurrence and lead to delayed treatment with antiepileptic drugs. It is mandatory to maintain a low threshold for suspecting epileptic seizures, and require appropriate electroencephalographic and neuroimaging investigations to promptly ascertain the etiology of any unexplained change in the neurological status and provide the most adequate treatment. This article is part of the Special Issue "Seizures & Stroke".

A novel computed tomography perfusion-based quantitative tool for evaluation of perfusional abnormalities in migrainous aura stroke mimic.

BACKGROUND: Migrainous aura (MA) represents the third most common stroke mimic (SM). Advanced neuroimaging is pivotal in the assessment of patients with focal neurological acute symptoms. We investigated brain perfusion alterations in MA-SM patients using a novel CT perfusion (CTP)-based quantitative approach in order to improve differential diagnosis between MA and acute stroke. METHODS: We processed and analysed the clinical and neuroimaging CTP data, acquired within 4.5 h from symptom onset, of patients with acute focal neurological symptoms receiving a final diagnosis of MA. The differences between ROI, compatible with MA symptoms, and contralateral side were automatically estimated in terms of asymmetry index (AI%) by the newly developed tool for mean transit time (MTT), CBF, and cerebral blood volume (CBV) CTP parameters. The AI% ≥ 10% was considered significant. RESULTS: Out of 923 admitted patients, 14 patients with MA were included. In 13 out of 14 cases, a significant pattern of hypoperfusion was observed by quantitative analysis in at least one of the CTP maps. In 7 patients, all three CTP maps were significantly altered. In particular, MTT-AI% increased in 11 (79%) cases, while CBF-AI% and CBV-AI% decreased in 12 (86%) and in 9 (64%) patients, respectively. All CBV values were above ischemic stroke core threshold and all MTT-AI were below ischemic penumbra threshold. CONCLUSIONS: Our data suggest that a novel CTP-quantitative approach may detect during MA a moderate hypoperfusion pattern in the cerebral regions compatible with aura symptoms. The use of this novel tool could support differential diagnosis between MA and acute stroke.

Paroxysmal hemicrania masquerading as a stroke in an elderly gentleman: case report.

BACKGROUND: Paroxysmal hemicrania has not been associated with ipsilateral weakness, loss of sensation and Horner's syndrome. This report is the first of its kind documented in literature. CASE PRESENTATION: This was an elderly, sixty-five-year-old Chinese male who presented with a headache fulfilling criteria of paroxysmal hemicrania and was found to have signs of ipsilateral conjunctival injection, Horner's syndrome, weakness and loss of sensation; with resolution of the patient's physical signs after relief of the headache. Brain magnetic resonance imaging did not show any strokes or other headache mimics. The patient had a marked response to indomethacin and a decrease of headache intensity and frequency with indomethacin prophylaxis. CONCLUSIONS: Paroxysmal hemicrania has joined the list of stroke chameleons and that it would be one of the differentials in a patient with hemiplegia, hemisensory loss, autonomic signs and severe headache. It suggests that paroxysmal hemicrania in the elderly present atypically.

A Helpful Tool in Diagnosing Stroke Mimics: Arterial Spin Labeled Perfusion Magnetic Resonance Imaging.

BACKGROUND: Prompt and effective management of acute ischemic stroke in the emergency setting requires a high level of suspicion and accurate diagnosis. Conversely, identifying stroke mimics can be challenging, given the similarity of their clinical symptomatology, the necessary rapid assessment and triage, and the overall frenetic pace inherent in the goal of rapid thrombolysis ("time is brain"). CASE REPORT: We describe a case that involves an elderly patient with acute hemiplegia and dysarthria. Given these concerning symptoms, and multiple preexisting cerebrovascular risk factors (including paroxysmal atrial fibrillation), a "stroke alert" was issued. Imaging was negative for infarct and she was ultimately diagnosed with hemiplegic migraine based on her symptoms and impressive findings on a novel magnetic resonance sequence called arterial spin labeled (ASL) perfusion. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Identifying a nonischemic etiology in a presumed stroke patient, while often difficult, can obviate unnecessary treatment, improve patient care, and promote appropriate resource allocation. As imaging and treatment of cerebrovascular disease advances, the optimization of multidisciplinary care should incorporate neuroradiologists informing and availing their clinical colleagues of applications of an ever-expanding imaging armamentarium. This case is an excellent example of both a common challenging stroke mimic and the potential benefits of ASL perfusion imaging in refining and expediting accurate diagnosis. In addition, it serves as a more general introduction to the particular strengths of this noninvasive, noncontrast magnetic resonance technique, which can be employed to assess varied emergent neuropathology.

Spinal epidural hematoma as a stroke mimic.

PURPOSE: Spinal epidural hematoma is a rare but important disease as it can be a stroke mimic. Our aim was to investigate the clinical characteristics of patients with an activated stroke code and spinal epidural hematoma. METHODS: Patients with an activated stroke code were examined retrospectively. Patients with spinal epidural hematoma were evaluated with further neurological examinations and neuroimaging. RESULTS: Of 2866 patients with an activated stroke code, spinal epidural hematoma was detected in 5 (0.2%, 63-79 years, 2 men). In all 5 cases, hematoma was located in the unilateral dorsal region of the spinal canal and spread to 5-9 vertebral segments at the C1-T3 level. None of the patients had a medical history of head or neck injury, coagulopathy, or use of anti-thrombotic agents. All of the patients had occipital, neck, and/or back pain, and their hemiparesis occurred simultaneously or within 1 h after the onset of pain. Hyperalgesia ipsilateral to the hematoma was observed in 1 patient, hypoalgesia contralateral to the hematoma was observed in 1, and quadriparesis and bilateral hypoalgesia were observed in 1. The hematomas spontaneously decreased in size in 4 patients, and cervical laminectomy was performed in the other patient. In the 1860 patients with an activated stroke code and spontaneous eye opening, the sensitivity of pain as a predictor of spinal epidural hematoma was 100%, with a specificity of 88.7%, and positive predictive value of 2.3%. CONCLUSION: Patients with spinal epidural hematoma could present with clinical characteristics mimicking ischemic stroke. Spinal epidural hematoma should be differentiated in patients treated under stroke code activation.

Migraine History: A Predictor of Negative Diffusion-Weighted Imaging in IV-tPA-Treated Stroke Mimics.

BACKGROUND: Migraine, seizures, and psychiatric disorders are frequently reported as "stroke mimics" in patients with negative diffusion-weighted imaging (DWI) after IV-tPA. We sought to determine predictors of negative DWI in suspected stroke patients treated with IV-tPA. METHOD: A retrospective case-control study encompassing all acute stroke patients treated with IV-tPA (at our hospital or "dripped and shipped") from January 2013 to December 2014 was con- ducted. A total of 275 patients were identified with 47 negative DWI cases and 228 positive DWI controls. Variables including demographic factors, stroke characteristics, and clinical comorbidities were analyzed for statistical significance. A multivariate logistic regression was performed (SPSS-24) to identify predictors of negative DWI. RESULTS: Approximately 17% of patients had negative DWI after IV-tPA. Compared to controls, migraine history independently predicted negative DWI (odds ratio [OR] 5.0 95% confidence interval [CI] 1.03-24.6, P = .046). Increasing age (OR .97 95% CI .94-.99, P = .02) and atrial fibrillation (OR .25 95% CI .08-.77, P = .01) predicted lower probability of negative DWI. Gender, admission NIHSS, treatment location, preadmission modified Rankin scale, diabetes mellitus, hypertension, hyperlipidemia, symptom side, seizure history, and psychiatric history did not predict negative DWI status. CONCLUSIONS: In our study, roughly 1 in 6 patients treated with IV-tPA were later found to be stroke mimics with negative DWI. Despite a high proportion of suspected stroke mimics in our study, only preexisting migraine history independently predicted negative DWI status after IV-tPA treatment in suspected stroke patients.