Sung-Il Sohn

Cerebellar infarction presenting isolated vertigo Frequency and vascular topographical patterns

Objective: To determine the frequency of cerebellar infarction mimicking vestibular neuritis (VN), the pattern of clinical presentation, and the territory of the cerebellar infarction when it simulates VN. Methods: We studied 240 consecutive cases of isolated cerebellar infarction in the territories of the cerebellar arteries diagnosed by brain MRI from the acute stroke registry at the Keimyung University Dongsan Medical Center. Results: We identified 25 patients (10.4%) with isolated cerebellar infarction who had clinical features suggesting VN. Two types of cerebellar infarction simulating VN were found: isolated spontaneous prolonged vertigo with imbalance as a sole manifestation of cerebellar infarction (n = 24) and isolated spontaneous prolonged vertigo with imbalance as an initial manifestation of cerebellar infarction (n = 1) followed by delayed neurologic deficits 2 days after the onset. The cerebellar infarction territory most commonly involved was the medial branch of the posterior inferior cerebellar artery territory (24/25: 96%), followed by the anterior inferior cerebellar artery territory (1/25: 4%). None of patients with infarcts in the territory of the superior cerebellar artery or multiple cerebellar arteries showed isolated spontaneous prolonged vertigo. Conclusions: Cerebellar infarction simulating vestibular neuritis is more common than previously thought. Early recognition of the pseudo-vestibular neuritis of vascular cause may allow specific management.

Safety and efficacy of MRI-based thrombolysis in unclear-onset stroke. A preliminary report

Background: Standard selection criteria for thrombolysis typically exclude patients with acute ischemic stroke with unclear onset. Multimodal MRI screening may be able to identify those with a favorable benefit-risk ratio for thrombolysis. We aimed to evaluate the safety and efficacy of MRI-based thrombolysis in unclear-onset stroke (UnCLOS). Methods: We reviewed the thrombolysis database registries from 3 medical centers in Korea. Subjects received thrombolysis with intravenous tissue plasminogen activator (tPA) or combined intravenous tPA and intra-arterial urokinase within 3 h, or intra-arterial urokinase within 6 h from symptom detection. For patients with UnCLOS, MRI-specific eligibility criteria (i.e. positive perfusion-diffusion mismatch and absence of well-developed fluid-attenuated inversion recovery changes of acute diffusion lesions) were applied. Rates of immediate and 5-day recanalization, early neurological improvement and symptomatic intracranial hemorrhage (ICH) within 48 h after treatment and 3-month modified Rankin Scale (mRS) scores were compared between patients with UnCLOS and those with clear-onset stroke (CLOS). Results: 32 patients with UnCLOS and 223 patients with CLOS were included. Baseline characteristics were comparable between the two groups, except that the proportion of MRI screening was higher, and detection-to-door time and door-to-needle time were longer in the UnCLOS group (p < 0.01). Rates of recanalization (immediate, 81.3 vs. 63.1%; delayed, 80.6 vs. 69.1%), early neurological improvement (on day 1, 46.9 vs. 35.9%; on day 7, 50.0 vs. 49.3%), symptomatic ICH (6.3 vs. 5.8%) and 3-month outcome (mRS 0–1, 37.5 vs. 35.0%; mRS 0–2, 50.0 vs. 49.3%) did not differ between the UnCLOS and CLOS groups. Conclusion: These preliminary results suggest that thrombolysis based on MRI criteria may safely be applied to acute stroke patients with unclear onset.

Early Reperfusion Rates with IV tPA Are Determined by CTA Clot Characteristics

These authors evaluated CTA studies of 228 patients paying special attention to the clot features, and correlated these features with early reperfusion rates. Clot features that predicted successful early reperfusion included: shorter clot, residual flow within the clot, and distal location. Reperfusion was achieved in only 8% of patients with longer and proximal clots and in those without residual flow. BACKGROUND AND PURPOSE: An ability to predict early reperfusion with IV tPA in patients with acute ischemic stroke and intracranial clots can help clinicians decide if additional intra-arterial therapy is needed or not. We explored the association between novel clot characteristics on baseline CTA and early reperfusion with IV tPA in patients with acute ischemic stroke by using classification and regression tree analysis. MATERIALS AND METHODS: Data are from patients with acute ischemic stroke and proximal anterior circulation occlusions from the Calgary CTA data base (2003–2012) and the Keimyung Stroke Registry (2005–2009). Patients receiving IV tPA followed by intra-arterial therapy were included. Clot location, length, residual flow within the clot, ratio of contrast Hounsfield units pre- and postclot, and the M1 segment origin to the proximal clot interface distance were assessed on baseline CTA. Early reperfusion (TICI 2a and above) with IV tPA was assessed on the first angiogram. RESULTS: Two hundred twenty-eight patients (50.4% men; median age, 69 years; median baseline NIHSS score, 17) fulfilled the inclusion criteria. Median symptom onset to IV tPA time was 120 minutes (interquartile range = 70 minutes); median IV tPA to first angiography time was 70.5 minutes (interquartile range = 62 minutes). Patients with residual flow within the clot were 5 times more likely to reperfuse than those without it. Patients with residual flow and a shorter clot length (≤15 mm) were most likely to reperfuse (70.6%). Patients with clots in the M1 MCA without residual flow reperfused more if clots were distal and had a clot interface ratio in Hounsfield units of <2 (36.8%). Patients with proximal M1 clots without residual flow reperfused 8% of the time. Carotid-T/-L occlusions rarely reperfused (1.7%). Interrater reliability for these clot characteristics was good. CONCLUSIONS: Our study shows that clot characteristics on CTA help physicians estimate a range of early reperfusion rates with IV tPA.

Early Recurrence and Cerebral Bleeding in Patients With Acute Ischemic Stroke and Atrial Fibrillation Effect of Anticoagulation and Its Timing: The RAF Study

Background and Purpose— The best time for administering anticoagulation therapy in acute cardioembolic stroke remains unclear. This prospective cohort study of patients with acute stroke and atrial fibrillation, evaluated (1) the risk of recurrent ischemic event and severe bleeding; (2) the risk factors for recurrence and bleeding; and (3) the risks of recurrence and bleeding associated with anticoagulant therapy and its starting time after the acute stroke. Methods— The primary outcome of this multicenter study was the composite of stroke, transient ischemic attack, symptomatic systemic embolism, symptomatic cerebral bleeding and major extracranial bleeding within 90 days from acute stroke. Results— Of the 1029 patients enrolled, 123 had 128 events (12.6%): 77 (7.6%) ischemic stroke or transient ischemic attack or systemic embolism, 37 (3.6%) symptomatic cerebral bleeding, and 14 (1.4%) major extracranial bleeding. At 90 days, 50% of the patients were either deceased or disabled (modified Rankin score ≥3), and 10.9% were deceased. High CHA2DS2-VASc score, high National Institutes of Health Stroke Scale, large ischemic lesion and type of anticoagulant were predictive factors for primary study outcome. At adjusted Cox regression analysis, initiating anticoagulants 4 to 14 days from stroke onset was associated with a significant reduction in primary study outcome, compared with initiating treatment before 4 or after 14 days: hazard ratio 0.53 (95% confidence interval 0.30–0.93). About 7% of the patients treated with oral anticoagulants alone had an outcome event compared with 16.8% and 12.3% of the patients treated with low molecular weight heparins alone or followed by oral anticoagulants, respectively (P=0.003). Conclusions— Acute stroke in atrial fibrillation patients is associated with high rates of ischemic recurrence and major bleeding at 90 days. This study has observed that high CHA2DS2-VASc score, high National Institutes of Health Stroke Scale, large ischemic lesions, and type of anticoagulant administered each independently led to a greater risk of recurrence and bleedings. Also, data showed that the best time for initiating anticoagulation treatment for secondary stroke prevention is 4 to 14 days from stroke onset. Moreover, patients treated with oral anticoagulants alone had better outcomes compared with patients treated with low molecular weight heparins alone or before oral anticoagulants.

Reperfusion Therapy in Unclear-Onset Stroke Based on MRI Evaluation (RESTORE) A Prospective Multicenter Study

Background and Purpose— Unclear-onset strokes are generally excluded from time-based thrombolytic therapy. We examined the safety and feasibility of magnetic resonance imaging-based reperfusion therapy in unclear-onset stroke. Methods— This prospective, multicenter, single-arm study screened consecutive unclear-onset stroke patients within 6 hours of symptom detection. Patients with perfusion-diffusion mismatch >20% and negative or subtle fluid-attenuated inversion recovery changes were treated with intravenous tissue plasminogen activator, intra-arterial therapy, or a combination. The safety outcome was symptomatic intracranial hemorrhage within 48 hours after treatment. The primary efficacy outcome was a 3-month modified Rankin Scale score of 0 to 2. Controls were untreated unclear-onset stroke patients prospectively captured in stroke registries. Results— Of 430 unclear-onset stroke patients, 83 (19.3%) received reperfusion therapy (mean age, 67.5 ± 10.4 years; males, 66.3%; median baseline National Institutes of Health Stroke Scale, 14). Symptomatic intracranial hemorrhage with any neurological decline developed in 5 patients (6.0%). Symptomatic intracranial hemorrhage with National Institutes of Health Stroke Scale worsening ≥4 developed in 3 patients (3.6%). Thirty-seven patients (44.6%) achieved modified Rankin Scale score of 0 to 2, and 24 (28.9%) had modified Rankin Scale score of 0 to 1. Female, baseline National Institutes of Health Stroke Scale score, no immediate or early recanalization, and more white blood cells were independent predictors of poor outcome. Compared with untreated controls, the treated group was significantly associated with good outcomes of modified Rankin Scale score of 0 to 2 after adjusting for age, sex, and baseline National Institutes of Health Stroke Scale in logistic regression analysis (odds ratio, 2.25; 95% CI, 1.14–4.49). Conclusions— In unclear-onset stroke patients, magnetic resonance imaging-based reperfusion therapy was feasible and safe. Randomized controlled trials are warranted to confirm the benefit of reperfusion therapy for unclear-onset stroke.

Cerebellar infarction in the territory of the medial branch of the superior cerebellar artery

The authors studied 14 patients with an isolated cerebellar infarct in the territory of the medial branch of the superior cerebellar artery (MSCA). The most common clinical finding was severe gait ataxia with sudden falling (n = 9) or severe veering (n = 2). Cerebellar dysarthria was found in 8 patients. Eight patients had a mild unilateral limb ataxia. These findings emphasize that MSCA territory cerebellar infarction presented with the prominent gait ataxia and cerebellar dysarthria.

Efficacy of early administration of escitalopram on depressive and emotional symptoms and neurological dysfunction after stroke: a multicentre, double-blind, randomised, placebo-controlled study.

BACKGROUND Mood and emotional disturbances are common in patients with stroke, and adversely affect the clinical outcome. We aimed to evaluate the efficacy of early administration of escitalopram to reduce moderate or severe depressive symptoms and improve emotional and neurological dysfunction in patients with stroke. METHODS This was a placebo controlled, double-blind trial done at 17 centres in South Korea. Patients who had had an acute stroke within the past 21 days were randomly assigned in a 1:1 ratio to receive oral escitalopram (10 mg/day) or placebo for 3 months. Randomisation was done with permuted blocks stratified by centre, via a web-based system. The primary endpoint was the frequency of moderate or severe depressive symptoms (Montgomery-Åsberg Depression Rating Scale [MADRS] ≥16). Endpoints were assessed at 3 months after randomisation in the full analysis set (patients who took study medication and underwent assessment of primary endpoint after randomisation), in all patients who were enrolled and randomly assigned (intention to treat), and in all patients who completed the trial (per-protocol analysis). This trial is registered with ClinicalTrials.gov, number NCT01278498. FINDINGS Between Jan 27, 2011, and June 30, 2014, 478 patients were assigned to placebo (n=237) or escitalopram (n=241); 405 were included in the full analysis set (195 in the placebo group, 210 in the escitalopram group). The primary outcome did not differ by study group in the full analysis set (25 [13%] patients in the placebo group vs 27 [13%] in the escitalopram group; odds ratio [OR] 1·00, 95% CI 0·56-1·80; p>0·99) or in the intention-to-treat analysis (34 [14%] vs 35 [15%]; OR 1·01, 95% CI 0·61-1·69, p=0·96). The study medication was generally well tolerated; the most common adverse events were constipation (14 [6%] patients who received placebo vs 14 [6%] who received escitalopram), muscle pain (16 [7%] vs ten [4%]), and insomnia (12 [5%] vs 12 [5%]). Diarrhoea was more common in the escitalopram group (nine [4%] patients) than in the placebo group (two [1%] patients). INTERPRETATION Escitalopram did not significantly reduce moderate or severe depressive symptoms in patients with acute stroke. FUNDING Dong-A Pharmaceutical and Ministry for Health, Welfare, and Family Affairs, South Korea.

Bilateral infarcts in the territory of the superior cerebellar artery: Clinical presentation, presumed cause, and outcome

BACKGROUNDS AND PURPOSE The aim of this study was to document the clinical presentation, vascular topographic patterns, stroke mechanism, and outcome of bilateral infarcts in the territory of the superior cerebellar artery (SCA) based on data collected from a prospective acute stroke registry. METHODS We studied the clinical and radiological features of 11 patients with bilateral infarctions in the territory of the SCA diagnosed by brain MRI. RESULTS Bilateral SCA infarcts represented 23.4% (11/47) of all SCA territory infarction. Bilateral SCA infarcts mostly associated with brainstem (n = 5), cerebral (n = 5), or non-SCA cerebellar lesions (n = 4). The most common clinical presentation at onset was sudden fall with axial lateropulsion and dysarthria (n = 6). In five patients with a coexisting infarct(s) in the brainstem, limb weakness and/or mental change were prominent and often masked the signs of cerebellar dysfunction. Six patients showed no stenosis or occlusion in the vertebrobasilar system on brain MRA. Five had an obvious cardiac source of emboli. Eight patients showed favorable outcomes with complete recovery or minimal disability, but three patients with additional extensive brainstem infarcts died within 1 week. CONCLUSIONS Bilateral SCA territory infarcts show variable clinical, vascular topographic, and prognostic features. They usually result from cardiac emboli.

Recurrent Ischemic Lesions After Acute Atherothrombotic Stroke: Clopidogrel Plus Aspirin Versus Aspirin Alone

Background and Purpose— In patients with acute ischemic stroke caused by large artery atherosclerosis, clopidogrel plus aspirin versus aspirin alone might be more effective to prevent recurrent cerebral ischemia. However, there is no clear evidence. Methods— In this multicenter, double-blind, placebo-controlled trial, we randomized 358 patients with acute ischemic stroke of presumed large artery atherosclerosis origin within 48 hours of onset to clopidogrel (75 mg/d without loading dose) plus aspirin (300-mg loading followed by 100 mg/d) or to aspirin alone (300-mg loading followed by 100 mg/d) for 30 days. The primary outcome was new symptomatic or asymptomatic ischemic lesion on magnetic resonance imaging within 30 days. Secondary outcomes were 30-day functional disability, clinical stroke recurrence, and composite of major vascular events. Safety outcome was any bleeding. Results— Of 358 patients enrolled, 334 (167 in each group) completed follow-up magnetic resonance imaging. The 30-day new ischemic lesion recurrence rate was comparable between the clopidogrel plus aspirin and the aspirin monotherapy groups (36.5% versus 35.9%; relative risk, 1.02; 95% confidence interval, 0.77–1.35; P=0.91). Of the recurrent ischemic lesions, 94.2% were clinically asymptomatic. There were no differences in secondary outcomes between the 2 groups. Any bleeding were more frequent in the combination group than in the aspirin monotherapy group, but the difference was not significant (16.7% versus 10.7%; P=0.11). One hemorrhagic stroke occurred in the clopidogrel plus aspirin group. Conclusions— Clopidogrel plus aspirin might not be superior to aspirin alone for preventing new ischemic lesion and clinical vascular events in patients with acute ischemic stroke caused by large artery atherosclerosis. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00814268.

Perverted head shaking nystagmus in focal pontine infarction

Although several papers have been published on perverted head shaking nystagmus (PHSN) associated with focal brainstem or cerebellar lesion, there are no reports of a focal pontine infarct that causes PHSN. We report a patient with focal pontine infarction who presented with sustained dizziness, limb dysmetria on the left extremity, decreased sensations to position and vibration of the left extremity, and gait imbalance. Only vestibular abnormality was downbeat nystagmus after vigorous head shakings. The maximum slow phase velocity of PHSN was 26°/s, and its duration was about 20s. This is the first report of PHSN associated with focal pontine infarction. Crossed ventral tegmental tract and velocity storage mechanism of vestibulocerebellum might be related on PHSN in this case.