Acute small subcortical infarctions on diffusion weighted MRI: clinical presentation and aetiology

[Neuroimaging Characteristics of Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) in Korean Based on Jeju Cohort: A Pictorial Essay]

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary small artery vasculopathy caused by mutations in the NOTCH3 gene on chromosome 19. Jeju Island has the highest reported prevalence of CADASIL patients in the world. Even though most studies on the neuroimaging characteristics of CADASIL have focused on Western populations, there are notable differences in Korean CADASIL patients compared to those in Western countries, which may impact their clinical manifestations and prognosis. Herein, this pictorial essay presents the neuroimaging patterns of CADASIL in patients in Korea, with an emphasis on the differences observed from previous reports based on a Western patient population.

Neuroimaging features of antiphospholipid antibody-related stroke compared with atrial fibrillation-related stroke

Recognizing the lesion pattern of antiphospholipid antibody-related stroke (aPL-stroke) may contribute to establishing the cause in patients with cryptogenic stroke. We aimed to describe the neuroimaging features of aPL-stroke compared with atrial fibrillation-related stroke (AF-stroke), a major hidden cause of cryptogenic stroke. Using a prospective stroke registry, we identified consecutive aPL- and AF-stroke patients without other potential causes of stroke. Neuroimaging features based on diffusion-weighted imaging and angiographic findings at admission were compared. A total of 56 and 333 patients were included in the aPL- and AF-stroke groups, respectively. aPL-stroke patients more often presented with single small lesions (aPL-stroke, 30.4% vs. AF-stroke, 7.5%, p < 0.001), while the predominant pattern in AF-stroke patients was large territorial lesions (26.8% vs. 56.5%, p < 0.001). aPL-stroke patients had smaller infarct volume (1.58 mL [0.45; 9.41] vs. 11.32 mL [2.82; 33.08], p < 0.001) and less experience of relevant artery occlusion (17.9% vs. 54.7%, p < 0.001). The proportion of multi-territory lesions, an embolic pattern, was similar between the two groups (28.6% vs. 22.8%, p = 0.44). In comparison only including patients with multi-territory lesions as well, aPL-stroke patients showed small lesion dominance and smaller infarct volume. Multivariate analyses showed independent associations between mild neuroimaging features (small lesion prevalence, smaller infarct volume, and absence of relevant artery occlusion) and aPL-stroke. Patterns of small lesion prevalence, small infarct volume, and absence of relevant artery occlusion were suggestive of aPL-stroke rather than AF-stroke. Cryptogenic stroke patients with such neuroimaging features may benefit from aPL testing for a precise diagnosis.

The Potential Impact of Neuroimaging and Translational Research on the Clinical Management of Lacunar Stroke

Lacunar infarcts represent one of the most frequent subtypes of ischemic strokes and may represent the first recognizable manifestation of a progressive disease of the small perforating arteries, capillaries, and venules of the brain, defined as cerebral small vessel disease. The pathophysiological mechanisms leading to a perforating artery occlusion are multiple and still not completely defined, due to spatial resolution issues in neuroimaging, sparsity of pathological studies, and lack of valid experimental models. Recent advances in the endovascular treatment of large vessel occlusion may have diverted attention from the management of patients with small vessel occlusions, often excluded from clinical trials of acute therapy and secondary prevention. However, patients with a lacunar stroke benefit from early diagnosis, reperfusion therapy, and secondary prevention measures. In addition, there are new developments in the knowledge of this entity that suggest potential benefits of thrombolysis in an extended time window in selected patients, as well as novel therapeutic approaches targeting different pathophysiological mechanisms involved in small vessel disease. This review offers a comprehensive update in lacunar stroke pathophysiology and clinical perspective for managing lacunar strokes, in light of the latest insights from imaging and translational studies.

Diagnostic value of diffusion-weighted STEAM-MRI in ischemic stroke

INTRODUCTION

Diffusion-weighted imaging in stimulated echo acquisition mode (STEAM-DWI) is an interesting alternative with less susceptibility artifacts compared to the most commonly used diffusion-weighted echo-planar imaging (EPI-DWI). Sensitivity and specificity of a novel STEAM-DWI, described by Merrem et al. 2017 [1], were assessed in patients with ischemic stroke.

METHODS

EPI- and STEAM-DWIs were performed in patients with suspected subacute stroke between 01 July 2019 and 30 June 2020 using 3-T MRI. Three neuroradiologists independently and separately rated STEAM-DWI images with respect to (i) signs of an acute/subacute stroke, (ii) the number, size and localization of infarctions and, (iii) the presence of artifacts.

RESULTS

In 55 (23 right, 23 left, 9 both hemispheres) of 85 patients a subacute stroke was confirmed using EPI-DWI. The cerebral vascular territories were affected as follows: anterior cerebral artery 8 %, middle cerebral artery 48 %, posterior cerebral artery 27 %, brainstem 7 %, cerebellum 10 %. In 53 of 55 (96 %) cases the stroke was detected by usage of STEAM-DWI, in 35 of 37 patients microembolic events were noticed (95 %). Results showed a sensitivity and specificity of 100 % (70/70) for major infarcts (>9 mm² in-plane) and a sensitivity of up to 94 % (121/129) for detecting subacute microembolic lesions. No susceptibility artifacts were noticed in STEAM-DWI.

CONCLUSION

Compared to standard EPI-DWI, STEAM-DWI offers a more robust alternative for diagnosing subacute strokes in areas affected by susceptibility artifacts.

Do Restoring and Maintaining Sinus Rhythm Have a Beneficial Effect on Secondary Prevention of Stroke in Patients With Atrial Fibrillation? A Pilot Study

We aimed to determine whether attempts to restore and maintain sinus rhythm will reduce recurrent stroke in patients with atrial fibrillation (AF). Patients (n = 245) between March 1998 and May 2002 with AF who had an ischemic stroke including transient ischemic attack 1 to 12 months before transesophageal echocardiographic examination and had been followed for 3 years were retrospectively reviewed. Cardioversion was attempted in 130 patients; 117 (90%) patients were successfully cardioverted (rhythm control group). The 13 patients who could not be cardioverted and 115 patients who did not undergo cardioversion were assigned to the rate control group. Age, gender, ischemic heart disease, hypertension, diabetes mellitus, congestive heart failure, mitral valve disease, and left atrial diameter were similar in both groups. The rhythm control group included 56 patients (48.7%) who were still in sinus rhythm after 3 years. During follow-up, there were 2 embolic events (3.4%) and 2 deaths (3.4%) in the rhythm control group, whereas 18 embolic events (14.6%) and 18 deaths (14.6%) occurred in the rate control group (P = .049 and P = .049, respectively). Restoration and maintenance of sinus rhythm seems to have a beneficial effect on secondary prevention of stroke in patients with AF.

Are morphologic features of recent small subcortical infarcts related to specific etiologic aspects?

Background:

Recent small subcortical infarcts (RSSIs) mostly result from the occlusion of a single, small, brain artery due to intrinsic cerebral small-vessel disease (CSVD). Some RSSIs may be attributable to other causes such as cardiac embolism or large-artery disease, and their association with coexisting CSVD and vascular risk factors may vary with morphological magnetic resonance imaging (MRI) features.

Methods:

We retrospectively identified all inpatients with a single symptomatic MRI-confirmed RSSI between 2008 and 2013. RSSIs were rated for size, shape, location (i.e. anterior: basal ganglia and centrum semiovale posterior cerebral circulation: thalamus and pons) and MRI signs of concomitant CSVD. In a further step, clinical data, including detailed diagnostic workup and vascular risk factors, were analyzed with regard to RSSI features.

Results:

Among 335 RSSI patients (mean age 71.1 ± 12.1 years), 131 (39%) RSSIs were >15 mm in axial diameter and 66 (20%) were tubular shaped. Atrial fibrillation (AF) was present in 44 (13.1%) and an ipsilateral vessel stenosis > 50% in 30 (9%) patients. Arterial hypertension and CSVD MRI markers were more frequent in patients with anterior-circulation RSSIs, whereas diabetes was more prevalent in posterior-circulation RSSIs. Larger RSSIs occurred more frequently in the basal ganglia and pons, and the latter were associated with signs of large-artery atherosclerosis. Patients with concomitant AF had no specific MRI profile.

Conclusion:

Our findings suggest the contribution of different pathophysiological mechanisms to the occurrence of RSSIs in the anterior and posterior cerebral circulation. While there appears to be some general association of larger infarcts in the pons with large-artery disease, we found no pattern suggestive of AF in RSSIs.

Clinical and Imaging Characteristics of Cerebral Infarction in Patients with Nonvalvular Atrial Fibrillation Combined with Cerebral Artery Stenosis

AIMS

Nonvalvular atrial fibrillation often occurs in combination with carotid atherosclerosis, but less is known about it in combination with cerebral artery stenosis. This study investigated the characteristics of cerebral infarction in patients with nonvalvular atrial fibrillation with or without cerebral artery stenosis.

METHODS

A retrospective analysis was conducted on 172 cerebral infarction patients with nonvalvular atrial fibrillation hospitalized at the Affiliated Ganzhou Hospital of Nanchang University between December 2011 and January 2016. The patients were divided into two groups (stenosis and non-stenosis groups) based on whether the cerebral infarction was combined with cerebral artery stenosis or not. Clinical characteristics, related supplementary examination, and the imaging characteristics of cerebral infarction lesions were compared between the groups.

RESULTS

Mean age [(75.73±8.46) years vs. (63.44±9.95) years], National Institute of Health stroke scale (NIHSS) score [(8.66±6.73) vs. (4.59±3.51)], CHA2DS2-VASc score [(2.93±1.40) vs. (0.96±0.98)], history of hypertension (74.4% vs. 30.0%), and history of stroke/ transient ischemic attack (TIA) (55.8% vs. 13.3%) were higher in the stenosis group (n=107) than in the non-stenosis group (n=65) (P＜0.01). In the stenosis group, there were different types of cerebral infarction lesions, including multiple infarction (multifocal type), massive infarction, watershed infarction, and lacunar infarction; in the non-stenosis group, the 60.0% lesions were multiple infarction (multifocal type), a significantly higher proportion than the stenosis group (26.2%, P＜0.05). NIHSS score was an independent risk factor for worse prognosis at follow-up (OR (95%CI) 1.251-1.674, P＜0.001).

CONCLUSIONS

Advanced age, hypertension, and stroke/TIA were increased in patients with cerebral infarction with nonvalvular atrial fibrillation combined with cerebral artery stenosis.

Significance of Multiple Acute Ischemic Lesions on Initial Diffusion-weighted Imaging in Stroke Patients and Relation of Toast Classification

Background

It is important to know whether or not the stroke risk factors and etiologies of patients with multiple acute infarcts are different to those of patients with a single acute infarct.

Aim

The frequency of multiple acute infarct was investigated in ischemic stroke patients and a comparison was made of the characteristics of stroke patients with and without multiple acute infarct.

Patients and Methods

We reviewed the clinical records of 988 ischemic stroke patients who were admitted within 1 week of the onset of stroke and diffusion-weighted imaging (DWI) was performed on first presentation. The clinical characteristics, laboratory, and imaging results were noted from the patient records. According to the DWI findings, the patients were separated into three groups as those with a single acute infarct in a single vascular territory (SI group), those with multiple acute infarcts in a single vascular territory (SMI group) and those with multiple acute infarcts in multiple vascular (MMI group) territories. The frequency of multiple acute infarcts was investigated, and a comparison was made of the characteristics of stroke patients with and without multiple acute infarcts.

Results

The SMI group included 119 (12%) patients and the MMI group 126 (12.8%). The most common mechanisms of multiple acute infarcts are large artery atherosclerosis and cardiac origin emboli. Moreover, the risk factors most determined were hypertension, diabetes mellitus, and hyperlipidemia in the MMI group.

Conclusion

No difference was determined between the groups in respect of stroke etiology and risk factors.

White matter hyperintensity lesion burden is associated with the infarct volume and 90-day outcome in small subcortical infarcts

OBJECTIVES

Small subcortical infarcts (SSI) frequently coexist with brain white matter hyperintensity (WMH) lesions. We sought to determine whether preexisting WMH burden relates to SSI volume, SSI etiology, and 90-day functional outcome.

MATERIALS AND METHODS

We retrospectively studied 80 consecutive patients with acute SSI. Infarct volume was determined on diffusion weighted imaging, and WMH burden was graded on fluid-attenuated inversion recovery sequences according to the Fazekas scale. SSI etiology was categorized as small vessel disease (SVD) vs non-SVD related. Multivariable linear and logistic regression models were constructed to determine whether WMH burden was independently associated with the SSI volume and a poor 90-day outcome (modified Rankin scale [mRS] score >2), respectively.

RESULTS

In unadjusted analyses, patients with non-SVD-related SSI were older (P=.002) and more frequently had multiple infarcts (P<.001) than patients with SVD-related SSI. In the fully adjusted model, WMH severity (Coefficient 0.07; 95%-CI 0.029-0.117; P=.002) but not SSI etiology (P>.1) was independently associated with the SSI volume. On multivariable logistic regression, worse WMH (OR 2.28; 95%-CI 1.04-4.99; P=.040), SSI etiology (OR 9.20; 95%-CI 1.04-81.39; P=.046), preadmission mRS (OR 8.96; 95%-CI 2.65-30.27; P<.001), and SSI volume (OR 1.98; 95%-CI 1.14-3.44; P=.016) were associated with a poor 90-day outcome.

CONCLUSIONS

Greater WMH burden is independently associated with a larger SSI volume and a worse 90-day outcome.

Morphological MRI characteristics of recent small subcortical infarcts

BACKGROUND

New imaging criteria for recent small subcortical infarcts have recently been proposed, replacing the earlier term 'lacunar infarction', but their applicability and impact on lesion selection is yet unknown.

AIMS

To collect information on the morphologic characteristics and variability of recent small subcortical infarcts on magnetic resonance imaging in regard to lesion location and demographic variables.

METHODS

We identified all patients with acute stroke and cerebral magnetic resonance imaging from 2008 to 2013 in our hospital database and selected those with a single recent small subcortical infarct defined by an estimated maximal axial diameter of 20 mm. Recent small subcortical infarcts were segmented on diffusion-weighted imaging and fluid-attenuated inversion recovery sequence to calculate the largest axial and longitudinal diameter and lesion volume. We assessed morphometric differences of recent small subcortical infarcts regarding location and demographic variables and the impact of different recent small subcortical infarct definitions on lesion selection.

RESULTS

Three hundred forty-four patients (median age 72; range 25-92 years, 65% male) were selected. Most recent small subcortical infarcts were located in the basal ganglia (n = 111), followed by pons (n = 92), thalamus (n = 77), and centrum semiovale (n = 64). Quantitative measurements confirmed visual assessment of the axial diameter in 95%. All morphometric variables were strongly intercorrelated and comparable on diffusion-weighted imaging and fluid-attenuated inversion recovery sequence. Recent small subcortical infarcts in the basal ganglia were significantly larger both in the axial and longitudinal direction compared with other regions. Dichotomization of recent small subcortical infarcts according to axial (≤ / >15 mm) or longitudinal (≤ / >20 mm) sizes resulted in different regional frequencies and distributions. Age, gender, and time from stroke onset to magnetic resonance imaging did not influence lesion metrics or the distribution of recent small subcortical infarcts.

CONCLUSIONS

Our study confirms the recent neuroimaging criteria for recent small subcortical infarcts as a practical concept. Definitions of the maximal axial and longitudinal diameter have a significant impact on the frequency and distribution of selected infarcts, which has to be considered for future studies.

Clinical correlates of infarct shape and volume in lacunar strokes: the Secondary Prevention of Small Subcortical Strokes trial

BACKGROUND AND PURPOSE

Infarct size and location are thought to correlate with different mechanisms of lacunar infarcts. We examined the relationship between the size and shape of lacunar infarcts and vascular risk factors and outcomes.

METHODS

We studied 1679 participants in the Secondary Prevention of Small Subcortical Stroke trial with a lacunar infarct visualized on diffusion-weighted imaging. Infarct volume was measured planimetrically, and shape was classified based on visual analysis after 3-dimensional reconstruction of axial MRI slices.

RESULTS

Infarct shape was ovoid/spheroid in 63%, slab in 12%, stick in 7%, and multicomponent in 17%. Median infarct volume was smallest in ovoid/spheroid relative to other shapes: 0.46, 0.65, 0.54, and 0.90 mL, respectively (P<0.001). Distributions of vascular risk factors were similar across the 4 groups except that patients in the ovoid/spheroid and stick groups were more often diabetic and those with multicomponent had significantly higher blood pressure at study entry. Intracranial stenosis did not differ among groups (P=0.2). Infarct volume was not associated with vascular risk factors. Increased volume was associated with worse functional status at baseline and 3 months. Overall, 162 recurrent strokes occurred during an average of 3.4 years of follow-up with no difference in recurrent ischemic stroke rate by shape or volume.

CONCLUSIONS

In patients with recent lacunar stroke, vascular risk factor profile was similar among the different infarct shapes and sizes. Infarct size correlated with worse short-term functional outcome. Neither shape nor volume was predictive of stroke recurrence.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00059306.

Neuroimaging standards for research into small vessel disease and its contribution to ageing and neurodegeneration

Cerebral small vessel disease (SVD) is a common accompaniment of ageing. Features seen on neuroimaging include recent small subcortical infarcts, lacunes, white matter hyperintensities, perivascular spaces, microbleeds, and brain atrophy. SVD can present as a stroke or cognitive decline, or can have few or no symptoms. SVD frequently coexists with neurodegenerative disease, and can exacerbate cognitive deficits, physical disabilities, and other symptoms of neurodegeneration. Terminology and definitions for imaging the features of SVD vary widely, which is also true for protocols for image acquisition and image analysis. This lack of consistency hampers progress in identifying the contribution of SVD to the pathophysiology and clinical features of common neurodegenerative diseases. We are an international working group from the Centres of Excellence in Neurodegeneration. We completed a structured process to develop definitions and imaging standards for markers and consequences of SVD. We aimed to achieve the following: first, to provide a common advisory about terms and definitions for features visible on MRI; second, to suggest minimum standards for image acquisition and analysis; third, to agree on standards for scientific reporting of changes related to SVD on neuroimaging; and fourth, to review emerging imaging methods for detection and quantification of preclinical manifestations of SVD. Our findings and recommendations apply to research studies, and can be used in the clinical setting to standardise image interpretation, acquisition, and reporting. This Position Paper summarises the main outcomes of this international effort to provide the STandards for ReportIng Vascular changes on nEuroimaging (STRIVE).

Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association

BACKGROUND AND PURPOSE

The authors present an overview of the current evidence and management recommendations for evaluation and treatment of adults with acute ischemic stroke. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators responsible for the care of acute ischemic stroke patients within the first 48 hours from stroke onset. These guidelines supersede the prior 2007 guidelines and 2009 updates.

METHODS

Members of the writing committee were appointed by the American Stroke Association Stroke Council's Scientific Statement Oversight Committee, representing various areas of medical expertise. Strict adherence to the American Heart Association conflict of interest policy was maintained throughout the consensus process. Panel members were assigned topics relevant to their areas of expertise, reviewed the stroke literature with emphasis on publications since the prior guidelines, and drafted recommendations in accordance with the American Heart Association Stroke Council's Level of Evidence grading algorithm.

RESULTS

The goal of these guidelines is to limit the morbidity and mortality associated with stroke. The guidelines support the overarching concept of stroke systems of care and detail aspects of stroke care from patient recognition; emergency medical services activation, transport, and triage; through the initial hours in the emergency department and stroke unit. The guideline discusses early stroke evaluation and general medical care, as well as ischemic stroke, specific interventions such as reperfusion strategies, and general physiological optimization for cerebral resuscitation.

CONCLUSIONS

Because many of the recommendations are based on limited data, additional research on treatment of acute ischemic stroke remains urgently needed.

Acute simultaneous multiple lacunar infarcts: a severe disease entity in small artery disease

BACKGROUND

We hypothesized that acute simultaneous multiple lacunar infarcts (sMLI) may have different clinico-radiological characteristics compared to acute single lacunar infarcts (SLI).

METHODS

We retrospectively reviewed stroke patients with sMLI or SLI in a consecutively collected stroke registry with a predefined long-term clinical follow-up. Clinical characteristics, including vascular risk factors, rheological profiles, premorbid functional status, and clinical outcome were evaluated. In addition, radiological characteristics, including white matter ischemic changes, previous lacunes, microbleeds, and concomitant intra- or extracranial arterial stenosis were evaluated.

RESULTS

Of the 548 acute ischemic stroke patients, sMLI was found in 23 (13.5%) and SLI in 148 (86.5%). There was no difference in vascular risk factors and rheological profiles between the two groups, except for advanced age and more frequent previous history of stroke in the sMLI group. The sMLI group also showed more previous lacunes (p < 0.001) and microbleeds (p < 0.001). A cardioembolic or atherothrombotic stroke mechanism was rare in both groups. Recurrent strokes were more frequent in the sMLI group.

CONCLUSIONS

The main pathophysiology of sMLI may be small artery disease. However, clinico-radiological characteristics suggest that sMLI may be a more severe entity of small artery disease compared to SLI.

Multiple subcortical acute ischemic lesions reflect small vessel disease rather than cardiogenic embolism

Multiple acute ischemic lesions in different hemispheres or vascular territories are mainly considered to be of proximal embolic origin. However, despite careful diagnostic work-up, the etiological classification often stays undetermined. We propose that multiple acute ischemic lesions can sometimes be a phenomenon observed in small vessel disease (SVD). From a prospectively collected database of more than 7,000 stroke patients, 173 patients with acute bihemispheric infarction were identified. We analyzed those subjects with multiple small (< 15 mm Ø) subcortical acute ischemic lesions on diffusion-weighted MRI (DWI) and concomitant severe small vessel disease (Fazekas grades II-III) without a proximal embolic source as evaluated by cardiological investigations. Twenty patients (mean age 66 ± 12 years, 12 men) with a mean number of 2.95 ± 1.24 acute lesions on DWI (range of 2-7 lesions per patient) were identified (n = 5 Fazekas II°, n = 15 Fazekas III°). Most of the lesions were located in typical areas of lacunar infarction. The mean NIHSS score on admission was 2.95 ± 2.0 (range 0-8). Multiple acute ischemic lesions in different vascular territories might not always be of proximal cardiovascular embolic origin. Simultaneous small subcortical ischemic lesions may reflect remote ischemia due to small vessel disease reflecting simultaneous hemorheological dysfunction.

Cerebral small vessel disease: a review of clinical, radiological, and histopathological phenotypes

Cerebral small vessel disease is difficult to directly visualize in vivo. Therefore, we rely on radiological phenotypes as surrogate markers of disease. The principal phenotypes of clinical interest are small, deep brain infarcts, cerebral white matter lesions, deep brain haemorrhages, and cerebral microbleeds. The causes or mechanisms underlying these phenotypes are understood in varying degrees of detail. This review aims to summarize recent knowledge regarding these phenotypes and place it in context with classical clinicopathological observations to provide mechanistic, clinical, and therapeutic insights into small vessel disease.

Differing risk factors and outcomes in ischemic stroke subtypes: focus on lacunar stroke

Lacunar stroke has been a recognized stroke subtype for many years but its pathophysiology remains unknown, so prevention and treatment are suboptimal. Most lacunar strokes result from an intrinsic cerebral small vessel disease, probably part of a systemic disorder. Hypertension, diabetes and other vascular risk factors (but not atrial fibrillation and ipsilateral carotid stenosis) are equally common in lacunar as in large artery atherothromboembolic stroke, which, together with other factors, suggests that the patient’s response to vascular risk factors, not the vascular risk factors per se, determines whether they develop small vessel or large artery stroke. Inflammation and endothelial failure are probably involved in the pathogenesis of lacunar stroke, but their role needs to be clarified. The cerebral venules as well as arterioles are abnormal in this condition. The disorder may not be primarily ischemic; instead, arteriolar thrombosis may be a late-stage phenomenon secondary to chronic arteriolar wall damage resulting from leakage of plasma components across the BBB. Accurate diagnosis of lacunar stroke, avoiding risk factor-based classifications, is required to underpin future research.

Topographic patterns and stroke subtypes according to progressive motor deficits in lacunar syndrome

Although progressive hemiparesis occurs frequently in acute ischemic stroke, the topography and mechanisms associated with progressive motor deficit (PMD) remain unclear. The aim of this study was to identify the differences in PMD according to lesion location and the presumed underlying pathogenesis in patients with lacunar motor syndrome. Consecutive patients experiencing acute lacunar motor syndrome within 24 hours of stroke onset were included. Topographic patterns, risk factors, and presumed stroke mechanisms were compared between patients with PMD and those without PMD. Of the 168 patients in the study group, 47 (28.0%) had PMD. Baseline National Institutes of Health Stroke Scale score (P = .034) and female sex (P = .005) were associated with PMD on univariate analysis. Deep perforating artery infarct was more frequently associated with PMD (35.8%) compared with large artery disease (27.3%) and cardioembolism (5.3%). Multiple logistic analysis found that deep perforating artery infarct was independently associated with PMD (odds ratio, 2.87; 95% confidence interval, 1.26-6.5; P = .012). Deep perforating artery infarct is the major cause of PMD. In patients with lacunar syndrome, the pattern of PMD varies according to the location and etiology of stroke.

Associations of clinical stroke misclassification ('clinical-imaging dissociation') in acute ischemic stroke

Background

Up to 20% of lacunar infarcts are clinically misdiagnosed as cortical infarcts and vice versa. The reasons for this discrepancy are unclear. We assessed clinical and imaging features which might explain this ‘clinical-imaging dissociation’ (C-ID).

Methods

Patients with an acute stroke syndrome (cortical or lacunar) underwent magnetic resonance imaging including diffusion-weighted imaging (DWI). We recorded DWI-positive infarcts and proximity to cortex for small subcortical infarcts. We examined factors associated with C-ID.

Results

137 patients with a mild cortical or lacunar syndrome had an acute ischemic lesion on DWI. Of these, 21/93 (23%) with a cortical syndrome had an acute lacunar infarct and 7/44 (16%) with a lacunar syndrome had an acute cortical infarct. From 72 patients with an acute lacunar infarct on DWI, lesion proximity to cortex (odds ratio (OR) 14.5, 95% confidence interval (CI) 1.61–130.1), left hemisphere location (OR 8.95, 95% CI 1.23–64.99) and diabetes (OR 17.1, 95% CI 1.49–196.16) predicted C-ID. On multivariate analysis of all 137 patients, C-ID was associated with diabetes (OR 7.12, 95% CI 1.86–27.2).

Conclusions

C-ID occurs in a fifth of patients with mild stroke. Lacunar infarcts lying close to cortex are more likely to cause cortical symptoms. Diabetes is associated with any clinical-imaging mismatch. Stroke misclassification which can arise with clinical classification alone should be minimized in research by verification with high-sensitivity imaging.

Clinical presentation and diffusion weighted MRI of acute cerebral infarction. The Bergen Stroke Study

Background

No large study has compared the yield of diffusion-weighted imaging (DWI) with clinical examination in order to differentiate lacunar stroke from other stroke subtypes. This differentiation is important for guiding further investigations and treatment.

Methods

Consecutive patients admitted with cerebral infarction were classified according to the Oxfordshire Community Stroke Project scale. Based on DWI and CT stroke was classified as lacunar (LI) and non-lacunar (NLI). Acute ischemic lesion <1.5 cm and located in subcortex or in brainstem were classified as LI. All other infarctions were classified as NLI.

Results

DWI was performed in 419 (69%) patients. Among patients with lacunar syndrome (LACS) 45 (40.5%) had NLI on DWI. All patients with total anterior syndrome (TACS) and 144 (88.3%) with partial anterior syndrome (PACS) had NLI on DWI.

Conclusion

DWI is important among patients presenting with clinical symptoms suggestive of lacunar syndrome to differentiate between LI and NLI. On the other hand, there is good correspondence between TACS or PACS and NLI on DWI.

Poststroke depression in patients with small subcortical infarcts

OBJECTIVES

Small subcortical infarcts (SSIs) can result from small vessel disease (SVD) and intracranial and extracranial large artery disease (LAD). No study has explored poststroke depression (PSD) in different etiological types of SSIs.

METHODS

Patients with SSIs resulting from LAD and SVD were included in the study. Poststroke depression was evaluated with the 15-item version of the geriatric depression scale (GDS) 3 months after stroke.

RESULTS

Of the 127 patients with SSIs, 44 had LAD and 83 had SVD. The LAD group had a significantly higher mean GDS score and higher frequency of PSD (p<0.05). The etiological type LAD was a significant independent risk factor for PSD.

CONCLUSION

PSD is more common in patients with SSIs resulting from LAD. This suggests that cerebral blood perfusion may play an important role in the development of PSD.

Clinical diagnosis of lacunar stroke in the first 6 hours after symptom onset: analysis of data from the glycine antagonist in neuroprotection (GAIN) Americas trial

BACKGROUND AND PURPOSE

Although the pathophysiological heterogeneity of stroke may be highly relevant to the development of acute-phase therapies, discriminating between ischemic stroke subtypes soon after onset remains a challenge. We conducted a study of the accuracy of a clinical diagnosis of lacunar stroke in the first 6 hours after symptom onset.

METHODS

We analyzed data from 1367 patients in the Glycine Antagonist In Neuroprotection (GAIN) Americas trial. The Trial of ORG10172 in Acute Stroke Treatment (TOAST) category "small vessel (lacunar)" disease at day 7 or at hospital discharge was used as the reference standard to determine the accuracy of a diagnosis of a lacunar stroke made within 6 hours of symptom onset using the Oxfordshire Community Stroke Project (OCSP) classification "LACS." Outcome was analyzed by comparing the proportions of patients classified as "LACS" at baseline or "small vessel (lacunar)" at 7 days who were dead or dependent at 3 months.

RESULTS

The positive predictive value of an OCSP diagnosis of a lacunar stroke was 76% (95% CI: 69% to 81%; sensitivity 64% [95% CI: 58% to 70%]; specificity 96% [95% CI: 95% to 97%]; negative predictive value 93% [95% CI: 92% to 94%]; accuracy 91% [95% CI: 89% to 92%]). The 3-month outcomes of patients classified as either OCSP "LACS" within 6 hours of onset or TOAST "small vessel (lacunar)" at 7 days were not significantly different.

CONCLUSIONS

An OCSP LACS diagnosis made within 6 hours of stroke onset is reasonably predictive of a final diagnosis of "small vessel (lacunar)" disease made using TOAST criteria and has a similar relationship to outcome at 3 months.

Guidelines for the Early Management of Adults With Ischemic Stroke

Purpose— Our goal is to provide an overview of the current evidence about components of the evaluation and treatment of adults with acute ischemic stroke. The intended audience is physicians and other emergency healthcare providers who treat patients within the first 48 hours after stroke. In addition, information for healthcare policy makers is included.

Methods— Members of the panel were appointed by the American Heart Association Stroke Council’s Scientific Statement Oversight Committee and represented different areas of expertise. The panel reviewed the relevant literature with an emphasis on reports published since 2003 and used the American Heart Association Stroke Council’s Levels of Evidence grading algorithm to rate the evidence and to make recommendations. After approval of the statement by the panel, it underwent peer review and approval by the American Heart Association Science Advisory and Coordinating Committee. It is intended that this guideline be fully updated in 3 years.

Results— Management of patients with acute ischemic stroke remains multifaceted and includes several aspects of care that have not been tested in clinical trials. This statement includes recommendations for management from the first contact by emergency medical services personnel through initial admission to the hospital. Intravenous administration of recombinant tissue plasminogen activator remains the most beneficial proven intervention for emergency treatment of stroke. Several interventions, including intra-arterial administration of thrombolytic agents and mechanical interventions, show promise. Because many of the recommendations are based on limited data, additional research on treatment of acute ischemic stroke is needed.

Guidelines for the early management of adults with ischemic stroke: a guideline from the American Heart Association/American Stroke Association Stroke Council, Clinical Cardiology Council, Cardiovascular Radiology and Intervention Council, and the Atherosclerotic Peripheral Vascular Disease and Quality of Care Outcomes in Research Interdisciplinary Working Groups: the American Academy of Neurology affirms the value of this guideline as an educational tool for neurologists

PURPOSE

Our goal is to provide an overview of the current evidence about components of the evaluation and treatment of adults with acute ischemic stroke. The intended audience is physicians and other emergency healthcare providers who treat patients within the first 48 hours after stroke. In addition, information for healthcare policy makers is included.

METHODS

Members of the panel were appointed by the American Heart Association Stroke Council's Scientific Statement Oversight Committee and represented different areas of expertise. The panel reviewed the relevant literature with an emphasis on reports published since 2003 and used the American Heart Association Stroke Council's Levels of Evidence grading algorithm to rate the evidence and to make recommendations. After approval of the statement by the panel, it underwent peer review and approval by the American Heart Association Science Advisory and Coordinating Committee. It is intended that this guideline be fully updated in 3 years.

RESULTS

Management of patients with acute ischemic stroke remains multifaceted and includes several aspects of care that have not been tested in clinical trials. This statement includes recommendations for management from the first contact by emergency medical services personnel through initial admission to the hospital. Intravenous administration of recombinant tissue plasminogen activator remains the most beneficial proven intervention for emergency treatment of stroke. Several interventions, including intra-arterial administration of thrombolytic agents and mechanical interventions, show promise. Because many of the recommendations are based on limited data, additional research on treatment of acute ischemic stroke is needed.

Delirium due to Brain Microembolism: Diagnostic Value of Diffusion-Weighted MRI

Delirum is a common complication in hospitalized patients and it is characterized by acute disturbances of consciousness, attention, cognition, and perception. Despite the frequency with which it is observed, ischemic stroke is generally considered as an unusual cause of delirium. A subtype of brain embolism is characterized by multiple small emboli in different vascular territories, a condition known as "brain microembolism." Given the high contrast of acute ischemic lesions in diffusion weighted imaging (DWI) this technique is particularly helpful to detect these small infarctions. We present here a patient with pulmonary metastases who was treated with bronchial artery embolization and who subsequently developed delirium due to brain microembolism. The embolic material crossed through pulmonary arteriovenous fistulas, producing multiple areas of cerebral ischemia. The ischemic lesions could be visualized only on DWI, and they affected the periventricular region, caudate nucleus, thalamus, and cerebellum.

Segmental left ventricular wall motion abnormalities are associated with lacunar ischemic stroke

OBJECTIVE

The aim of this study was to determine whether segmental left ventricular wall motion abnormalities (SLVWMA) are a potential cause of ischemic stroke.

METHODS

Demographics, cardiovascular risk factors and echocardiographic parameters of patients with ischemic stroke (with and without SLVWMA) were collected and compared with those of patients who had SLVWMA but without history of ischemic stroke.

RESULTS

Two hundred and fifty nine patients with ischemic stroke were identified: 187 patients without SLVWMA, and 72 with SLVWMA. The cardiac group consisted of 79 patients. Compared with the stroke patients with SLVWMA, stroke patients without SLVWMA were slightly but significantly younger (59 versus 63 years of age). Furthermore, the number of risk factors in stroke patients without SLVWMA was significantly lower compared with stroke patients with SLVWMA (2.7 versus 3.7). There was no difference in age or gender between stroke patients with SLVWMA and the cardiac patients. However, the number of risk factors was significantly higher in the cardiac patients compared with stroke patients with SLVWMA (4.4 versus 3.7). The ejection fraction was normal in both groups of stroke patients but significantly lower in the cardiac patients (37%). Significantly more lacunar ischemic strokes were observed in stroke patients with SLVWMA than in those without SLVWMA (76% versus 68%).

CONCLUSION

Our data indicate that in ischemic stroke patients with multiple cardiovascular risk factors and SLVWMA a higher frequency of lacunar strokes can be found. The latter could be a marker of small-vessel disease and/or be a potential contributing factor, perhaps through a mechanism of cardiac microembolism, in the development of lacunar ischemic stroke. The mechanisms of the association between SLVWMA and lacunar ischemic stroke remain however unclear.