Inducing neuroplasticity

There are many parallels between postlesional neuro-plasticity (re-learning) and normal learning in the development of human individuals leading to changes of behavior by repetitive interactions with the social environment. In clinical neurorehabilitation the main effect of the multidisciplinary teamwork and applied therapies is to create a stimulating learning atmosphere that matches the patient's individual needs and deficits. Such learning conditions also take place in the therapeutic...

Demographic and medical characteristics of the patient

The most important demographic predictors of dementia after stroke, in sufficiently powered studies, are increasing age and low education level, but not gender when the analysis is adjusted for age 5 . The risk of dementia after stroke is higher in patients who were already dependent before stroke 5 . Pre-stroke cognitive decline without dementia, assessed by standardized questionnaires, is also associated with a higher risk of dementia after stroke 5, 32 . Diabetes mellitus, atrial...

CT angiography

Cerebral and cervical CT angiography is performed using intravenous administration of 50 ml of iodinated contrast material at a rate of 3 ml per second, and an acquisition delay of about 15 seconds. Data acquisition is performed from the origin of the aortic arch branch vessels to the circle of Willis and reconstructed as maximum-intensity projections (MIP) (Figure 3.3E) and three-dimensional reconstructions (Figure 3.3B). Figure 3.3. Same patient as in Figure 3.2. Upper row imaging at 12 hours...

Multiple overlapping causes of ischemic stroke

In some patients multiple overlapping causes of ische-mic stroke are identified. In such cases, whether these findings are purely coincidental or represent the cause of the infarct is not clear. For example, patients with clinical and neuroimaging features that are compatible with lacunar infarction may have associated findings of large artery atherosclerosis or a cardioembolic source (most commonly atrial fibrillation). In one study, 4 of all stroke patients had small artery disease coexisting...

Cryptogenic ischemic stroke

Patients experiencing a TIA stroke frequently have no determined etiology after standard diagnostic evaluation. Previous reports show that 20-25 of stroke survivors are classified as cryptogenic stroke, but it is a matter of debate which strokes should be labeled cryptogenic - what level of evidence is needed for accepting a finding or risk factor as the cause Such debate has surrounded PFO, which can be an incidental finding or possibly an underlying mechanism methods for distinguishing...

Role of functional imaging in stroke patients

The functional deficit after a focal brain lesion is determined by the localization and the extent of the tissue damage recovery depends on the adaptive plasticity of the undamaged brain, especially the cerebral cortex, and of the non-affected elements of the functional network. Since destroyed tissue usually cannot be replaced in the adult human brain, improvement or recovery of neurological deficits can be achieved only by reactivation of functionally disturbed but morphologically preserved...

Extracranial ultrasound in acute stroke

The most important diagnostic question in ultrasono-graphy is which extra- and intracranial vessel(s) is are stenotic or occluded and can it they be responsible for the clinical symptoms. Note that clinically silent sten-otic processes might also influence the cerebral circulation. Because ofthe interactions between extra- and intra-cranial hemodynamics, both extracranial and intracra-nial ultrasound techniques should be performed in acute stroke. Similarly, clinically silent stenoses should be...

Diagnostic brain perfusion imaging in stroke patients

The availability of new ultrasound contrast agents (UCAs) and the development of contrast-specific imaging modalities have established the application of ultrasound in stroke patients for visualization of brain perfusion deficits. The UCAs consist of micro-bubbles composed of a gas that is associated with various types of shells for stabilization. Because of their small size, they can pass through the microcirculation. There are interactions between ultrasound and microbubbles at low ultrasound...

Prognostic value of ultrasound in acute stroke

During recent years, ultrasound has become an important non-invasive imaging technique for bedside monitoring of acute stroke therapy and prognosis. By providing valuable information on temporal patterns of recanalization, ultrasound monitoring may assist in the selection of patients for additional pharmacological or interventional treatment. Ultrasound also has an important prognostic role in acute stroke. A prospective, multicenter, randomized study confirmed that a normal MCA finding is...

Overall lifestyle patterns and stroke risk

Recently, in the analysis of the data from the Health Professionals Follow-up Study and from the Nurses' Health Study the impact on stroke risk of a combination of healthy lifestyle characteristics was evaluated and the burden of stroke that may be attributed to these unhealthy lifestyle choices was calculated 31 . Diet and other lifestyle factors were updated from self-reported questionnaires. A low-risk healthy lifestyle was defined as (i) not smoking, (ii) a body mass index < 25kg m2,...

Diagnosis of coronary heart disease in stroke patients

When caring for stroke patients in the acute or rehabilitation phase, it is necessary to be aware of clinical symptoms of myocardial ischemia such as chest pain or exertional dyspnea, or electrocardio-graphic abnormalities such as ST-depression, T-wave abnormalities or newly developing Q-waves 20 . The detection of myocardial injury can be improved by measuring serum levels of troponin T or troponin I, biomarkers which are found to be highly specific for myocardial necrosis 24 . Elevated...

Myocardial infarction as a cause of embolism

Cardiogenic embolism from a left ventricular thrombus may occur as a complication of acute or subacute myocardial infarction or due to a ventricular aneur-ysm in the chronic phase of a large, mainly anterior wall infarction 27 . The incidence of left ventricular thrombi early after myocardial infarction has declined in recent years, most probably due to changes in the acute therapy of myocardial infarction, which now comprises intensive anticoagulant therapy and percutaneous coronary...

Relative risk of dementia after stroke

In the Rochester study, the relative risk of dementia (i.e. the risk of dementia in stroke survivors divided by the risk of dementia in stroke-free controls) was 8.8 one year after stroke, then declined progressively to 2.5 after 10 years, and 2.0 after 25 years 22 . The risk of AD was also doubled after 25 years 22 . In the Framingham study, the results were similar 10 years after stroke, after adjustment for age, gender, education level and exposure to individual risk factors for stroke 29 ....

Preexisting silent brain lesions in stroke patients

Silent infarcts, i.e. cerebral infarcts seen on CT or MRI scans that have never been associated with a relevant neurological deficit, are associated with an increased risk of dementia after stroke 5 . Their influence is more important when the follow-up is longer in the Lille study, silent infarcts were associated with dementia after stroke at year 3 25 but not at year 2 and in the Maastricht study silent infarcts were independently related to dementia after 12 months, but not after 1 or 6...

Pregnancy after an ischemic stroke

A multicenter French study 79 conducted with 373 consecutive women who had an ischemic stroke between 15 and 40 years of age and followed-up over a 5-year period found an overall risk of recurrent stroke of 0.5 at year 5 (95 CI 0.3-0.95) in periods without pregnancy and 1.8 (95 CI 0.5-7.5) during pregnancies and puerperium, without significant difference. Therefore young women who have had an ischemic stroke have an overall low risk of recurrence during a subsequent pregnancy and do not...

Secondary prevention after ischemic stroke in young adults

The main characteristics of ischemic stroke occurring in young patients, i.e. their causes, the overall good outcome and interference with hormonal life in women (contraception, pregnancy and future menopause), influence secondary prevention after stroke. As for elderly subjects, secondary prevention measures mainly depend on the presumed cause. For this reason, an extensive and early diagnostic work-up is required, as well as an extensive evaluation of risk factors. The overall management of...

Management of acute ischemic stroke and its complications

General management of elevated blood pressure, blood glucose and body temperature Monitoring the blood pressure (BP), glucose levels and temperature in acute stroke patients is an often neglected matter although it may have an important impact upon the patients' outcome. In the Tel Aviv stroke register, recorded between the years 2001 and 2003, 32 of acute stroke patients in the emergency room had glucose levels higher than 150 mg dl, higher systolic BP than 140 mmHg was found in 77 of the...

Hypertensive blood pressure values in acute ischemic stroke

Several observations have demonstrated spontaneous elevation of blood pressure in the first 24-48 hrs after stroke onset with a significant spontaneous decline after a few days 1-3 . Several mechanisms may be responsible for the increased blood pressure, including stress, pain, urinary retention, Cushing effect due to increased intracranial pressure and the activation of the sympathetic, renin-angiotensin and ACTH-cortisol pathways. Despite the increased prevalence of hypertension following...

Controlling BP in the acute stroke phase

The theory that elevated systemic BP may compensate for the decreased cerebral blood flow in the ischemic region led to attempts to elevate blood pressure as a treatment for acute ischemic stroke. The hemody-namic and metabolic impact of pharmacologically increased systemic blood pressure on the ischemic core and penumbra was evaluated in rats. The mild induced hypertension was found to increase collateral flow and oxygenation and to improve cerebral metabolic rate of oxygen in the core and...

Stroke risk and PFO

It is uncertain whether the recurrence rate of stroke in patients with cryptogenic stroke is dependent on the presence of a PFO. In one observational study of patients treated with aspirin, the incidence of recurrent stroke was higher in patients with than without PFO 47 . In a further prospective randomized study, the recurrence rate of stroke was the same in those with or without PFO in those treated with either warfarin or aspirin 44 . The question of whether subjects from the general...

Advantages of centralized stroke management organization

In Finland, as in most Scandinavian countries, stroke care is organized in a more straightforward and centralized manner if compared to most EU countries and the USA. The EMS organization consists of a national ERC administration providing emergency response services for the entire country. There are no overlapping EMS services, and in many areas only one EMS provider, supervised by an EMS physician at the university hospital or regional hospital. Furthermore, only one hospital is in charge for...

Anger and aggressiveness

Anger and aggression are complex human emotions and behaviors depending on several anatomical structures, including the frontal lobes, the amygdala, the hypothalamus and the brainstem. Anger is a primary emotion with three components the emotional (anger), the cognitive (hostility) and the behavioral (aggression). A few studies 30-34 have evaluated anger and its components systematically in stroke patients and found a frequency ranging from 17 to 34 . In some studies, anger in stroke patients...

Arterial dissection uncommon clinical presentations

Bogousslavsky et al. 37 found an incidence of arterial dissection of 2.5 in 1200 consecutive first stroke patients. Under the age of 45 the incidence of cervical artery dissection (CAD) is much higher at 10-25 and CAD is the second leading cause of stroke in younger adults 38 . Most patients with dissections are between 30 and 50 years of age, and the mean age is approximately 40 years. The annual incidence of cervical internal carotid artery dissection was found to be 3.5 per 100000 in those...

Aspirin

The benefits of low-dose aspirin in preventing recurrent serious vascular events in patients with transient ischemic attack, ischemic stroke or myocardial infarction have been established for more than 10 years 13 . The potential benefits of commencing aspirin therapy in patients early after the onset of ischemic stroke were not realized until the publication of two large randomized controlled trials, the Chinese Acute Stroke Trial (CAST) and the International Stroke Trial (IST) 14, 15 . With a...

Atrial fibrillation

Loop Recorder Implant

AF is a cardiac arrhythmia, defined by the absence of P waves and varying RR distances in the electrocardiogram. AF is a common arrhythmia and its prevalence increases with age up to 9 at age 80-89 years (Figure 7.1). Approximately 85 of the individuals with AF are between 65 and 85 years of age 1 . Apart from hemodynamic consequences due to the loss of atrial contraction and symptoms, such as palpitations, AF may lead to embolic stroke or peripheral or mes-enteric embolism. Compared to...

Blood pressure and outcome

Analysis of 17 398 patients in the International Stroke Trial 4 demonstrated a U-shaped relationship between baseline systolic blood pressure and both early death and late death or dependency. Both high blood pressure and low blood pressure were independent prognostic factors for poor outcome. Early death increased by 17.9 for every 10 mmHg below 150 mmHg (P < 0.0001) and by 3.8 for every 10 mmHg above 150 mmHg (P 0.016). A prospective study among 1121 patients admitted within 24 hours from...

BP and outcome in thrombolysed patients

Several observations, including the NINDS-tPA trial 8, 9 , found an association between high blood pressure on admission, and its prolongation, with poor outcome and mortality. Although in one study no such association was found in alert patients, stroke patients with impaired consciousness showed higher mortality rates with increasing blood pressure 10 . The association between elevated blood pressure and recanalization was evaluated in 149 patients after intra-arterial thrombolysis using...

Cardioembolic stroke

Cardioembolic stroke accounts for 25-35 of all ischemic strokes, making cardiac disease the most common major cause of stroke overall - a practical point often forgotten. Non-valvular atrial fibrillation is the commonest cause of cardioembolic stroke. The heart is of particular importance in ischemic stroke for other reasons also cardiac disorders (in particular coronary heart disease) frequently co-exist in patients with stroke and are important long-term prognostic determinants. Whereas...

Cardioembolism

The main causes of cardioembolism in young patients are listed in Table 14.1. A few of them deserve more detail. Atrial fibrillation is associated with a very low risk of cerebral emboli in young people when occurring in the absence of underlying cardiopathy (lone atrial fibrillation) and of vascular risk factors. However, it confers a high risk of cerebral emboli when there are Table 14.1. Main cardiac sources of cerebralischemia in young adults. atrial fibrillation associated with...

Chapter Summary

The Trial of Organon in Acute Stroke (TOAST) classification divides ischemic stroke into atherothrombotic (30 of ischemic strokes, mostly emboli from the bifurcation of the carotid artery) cardioembolic (25-35 of ischemic strokes, mostly due to atrial fibrillation) small-vessel occlusion (25 of ischemic strokes, leading to lacunar infarcts) Sometimes, overlapping causes can be identified. Large artery atherosclerosis is estimated to account for about 30 of all ischemic strokes. Large-vessel...

Cognitive recovery after stroke

Besides defined neuropsychological syndromes, cognitive impairment after a stroke is very common and may persist in the postacute and also the chronic phase. Individual assessment includes evaluation of several aspects of attention, intelligence, memory, executive functions and personality prior to devising an individual treatment schedule, which can be neu-ropsychologically specific but should also be interdisciplinary, as the impairment usually has an impact on several aspects of the...

Conclusions

Recognition of dementia in stroke patients is important because it indicates a worse outcome with higher mortality rates, more recurrences and more functional impairment. Research should now focus on a delineation of the concept of post-stroke cognitive decline without dementia, which may be a preliminary stage of dementia after stroke, be much more frequent in practice, and be a better target for therapeutic approaches. Other epidemiological studies are also necessary to evaluate the evolution...

CVT in neonates

While the symptomatology, etiology and therapy of CVT in older children resemble those of adult CVT in most respects, in neonates the causes, clinical presentation, outcome, and management are very different. Manifestation of CVT in neonates seems to be associated with maternal risk factors (hypertension, pre- eclampsia, gestational or chronic diabetes mellitus). The vast majority of neonates present with an acute illness at the time of diagnosis, most often dehydration, cardiac defects, sepsis...

Delirium

Delirium is a disturbance of consciousness, with a change in cognition or development of a perceptual disturbance, which develops over a short period, fluctuates during the course of the day and cannot be explained by pre-existing dementia (Table 12.7). Stroke is a rare cause of delirium. On the other hand, delirium often (15-48 ) complicates acute stroke 25-28 . Delirium must be differentiated clinically from disorientation in time, topographical disorientation, delusions and hallucinations,...

Dyslipidemia

Older epidemiological studies found no relationship between total serum cholesterol level and overall stroke incidence 111 . This might be due to different relationships for ischemic and intracerebral hemorrhages. In prospective cohort studies stroke risk was found to be positively associated with serum cholesterol level in ischemic stroke but negatively for intra-cerebral hemorrhages 112 . Age, sex and vascular risk factors can modify the relationship between blood cholesterol and vascular...

Early activities at a stroke unit

The time window for treatment of patients with acute stroke is narrow and requires well-organized services at the ED and acute stroke unit. The points which must be kept in mind include acute emergency management of stroke requires parallel processes at different levels of patient management acute assessment of neurological and vital functions parallels treatment of acutely life-threatening conditions Table 15.3. Components considered as absolutely necessary for a CSC by 75 (in bold) or 50 of...

Early rehabilitation

Rehabilitation of stroke patients will be discussed in Chapter 19. All patients need to be assessed at the stroke unit by a physiotherapist, occupational therapist, speech therapist and neurophysiologist of the multidisciplinary stroke team within the first week after the onset of stroke. There is great variability in rehabilitation resources and staff between geographical regions and hospitals, but in general all available therapists should be involved in the early assessment and design of the...

Earlyonset infectious complications

Infectious complications after acute stroke are common. In a prospective study of 3866 patients with ischemic stroke hospitalized in neurological stroke units in Germany, 7.4 developed pneumonia and 6.3 urinary tract infections within 7 days after cerebral infarction 34 . Other studies report an even higher incidence of urinary tract infections and pneumonia, 24 and 22 respectively 35 . Stroke-associated pneumonia is associated with a higher fatality and worse long-term clinical outcome 34, 36...

Elevated intracranial pressure

The most common cause of death in the acute stage of a major stroke is increased intracranial pressure and her-niation due to brain edema. Decompressive craniect-omy has now a class I level A recommendation in malignant ischemic MCA stroke patients younger than Table 15.8. ESO Guidelines for specific treatments 2 . Intravenous rtPA (0.9mg kg body weight, maximum 90 mg), with 10 of the dose given as a bolus followed by a 60-minute infusion, is recommended within 3 hours of onset of ischemic...

Epidemiology

Figures depend on the definition of young. Three upper thresholds can be found in the literature, at 30, 45 and 55 years of age. The most frequently used upper age limit is 45 years. It constitutes a good compromise between an age category where common causes of cerebral ischemia, such as ather-oma, atrial fibrillation and lipohyalinosis, are very rare, and on the other hand a disorder that is not too rare. The incidence of ischemic strokes increases with age even in young people most young...

Etiology

CVT may be due to infectious and non-infectious causes. Septic CVT is observed as a complication of bacterial infections of the visceral cranium, namely otitis, sinusitis, mastoiditis and bacterial meningitis. The infectious agents reach the cerebral sinuses ascending Table 11.1. Potentialcauses of and risk factors associated with cerebralvenous thrombosis 3, 4, 14 . Mutations in the methylenetetrahydrofolate reductase (MTHFR) gene Systemic infectious disease Inflammatory disease Systemic lupus...

Fasttrack neurovascular ultrasound examination

Recently, a practical algorithm has been published for urgent bedside neurovascular ultrasound examination with carotid vertebral duplex and transcranial Doppler in patients with acute stroke 11, 12 . Using such a protocol, urgent TCD studies can be completed and interpreted quickly at the bedside. The expanded fast-track protocol for combined carotid and transcranial ultrasound testing in acute cerebral ischemia is shown in Table 4.4. Below, we highlight the most important details of the...

Heparin for cardioembolic stroke

The International Stroke Trial investigated the use of aspirin and subcutaneous unfractionated heparin in a two-by-two factorial design. The beneficial effects of aspirin have already been discussed but the study also identified three fewer deaths within 14 days per 1000 patients treated with heparin (non-significant) and significantly fewer early recurrent strokes (2.9 vs. 3.8 ) and pulmonary emboli (0.5 vs. 0.8 ) 14 . After 6 months, however, the mortality rate was identical in those patients...

Hyperthermia

Several animal studies 35, 36 demonstrated the correlation of elevated temperature and poor outcome in ischemic stroke models. Similar results were found in human observations. In the Copenhagen stroke study 37 stroke severity was correlated with hyperthermia higher than 37.5 C, while a temperature lower than 36.5 C was associated with a favorable outcome. Other studies limited the correlation between stroke severity and hyperthermia to only the first 24 hours following stroke onset. In a...

Imaging of penumbra

Based on the threshold concept of brain ischemia, the penumbra can be localized on quantitative flow images using established flow thresholds. A more direct approach is the imaging of threshold-dependent biochemical disturbances and demarcating the mismatch between disturbances which occur only in the infarct core and others which also affect the penumbra 59 (Figure 1.7). Under experimental conditions the most reliable way to localize the infarct core is the loss of ATP on bioluminescent images...

IMT measurement

In the Cardiovascular Health Study, increases in the intimal-medial thickness (IMT) of the carotid artery were associated with an increased risk of myocardial infarction and stroke in older adults without a history of cardiovascular disease 4 . CCA IMT greater than 0.87 mm and ICA IMT greater than 0.90 mm were associated with a progressively increased risk of cardiovascular events. For each 0.20 mm increase in CCA IMT, the risk increased by approximately 27 . For each 0.55 mm increase in ICA...

Incidence and prevalence rates

ICH, like ischemic stroke, has a clear age-dependent incidence rate, occurring slightly earlier in life than ischemic attacks. Most population-based registries report an incidence of 10 per 100 000 per year, and variations exist towards higher rates in some populations. A decrease of rates has been reported over time from several regions of the world. While the exact reasons for this decline are not known, it is reasonable to assume that a decline in rates as well as severity of arterial...

Incidence mortality and case fatality

There are several issues related to the occurrence of stroke that are important from an epidemiological (and clinical) perspective. While it would be useful to know the incidence (occurrence of first stroke events), in most populations data may be available on mortality from stroke only, but not on non-fatal events. The case fatality at the stroke event, usually determined as the proportion of deaths occurring during the first 4 weeks after the onset of stroke event, gives information about the...

Incidence of newonset dementia in stroke survivors

Incidence studies are limited by similar methodological issues 5 . The incidence of dementia after stroke depends on whether the study excluded patients with pre-existing cognitive decline or dementia or not. Many so-called PSDs are not actually new-onset dementia, but pre-existing dementia revealed after stroke, pre-existing dementia being present in 7-16 of stroke patients, and often undiagnosed before stroke 15-21 . In a community-based study conducted over a 25-year period, the cumulative...

Infective endocarditis and stroke

Ischemic and hemorrhagic strokes occur in 10 to 23 of patients with endocarditis and cluster during the period of untreated infection 29-31 . Among patients with endocarditis and stroke, the mitral valve seems to be more frequently affected than the aortic valve 30, 31 . Native valves as well as prosthetic valves may be affected by endocarditis, leading to stroke. Stroke patients with prosthetic valves have a worse prognosis than patients with native valves 32, 33 . Despite the availability of...

Introduction

This chapter focuses on the major causes of ischemic stroke. Common and less common stroke syndromes are described in Chapters 8 and 9. Ischemic stroke is not a single disease but a heterogeneous condition with several very different pathophysiological mechanisms. Identification of the underlying cause is important for several reasons. It helps to group patients into specific subtypes for the study of different aspects of prognosis, which may be used for planning and information purposes. It...

Lacunar stroke syndromes

Lacunes are defined as small subcortical infarcts less than 1.5 cm in diameter occurring in perforator territories. Together with leukoaraiosis, microbleeds, and hypertensive (deep) intracerebral hemorrhages, they are part of the spectrum of small-vessel disease. This disease is tightly related to chronic hypertension, but diabetes, male gender, increasing age, smoking, previous lacunar TIA or stroke, and coronary artery disease are also risk factors. About 20 of all strokes are considered to...

Language disorders

Language disorders, or aphasia, occur following peri-sylvian lesions (middle cerebral artery territory) of the left hemisphere and have a marked impact on the individual quality of life, autonomy and the ability to return to work or previous activities. Since these lesions are circumscribed, the conceptual representation system is not affected and these patients are not demented. This is an important distinction that should be explained to the family and caregivers. Language disorders occur...

Large artery atherosclerosis

Atherosclerosis of the major vessels supplying the brain is an important mechanism in ischemic stroke. Although the common occurrence of atherosclerosis in the region of the carotid bifurcation was observed early in the twentieth century, and the mechanism of distal embolization in causing strokes was proposed, it was widely assumed that most cerebral ischemic strokes were caused by in situ middle cerebral artery (MCA) thrombosis. The full implications of extracranial atherosclerosis for...

Large artery atherosclerosis in the aortic arch

The link between atherosclerosis of the aortic arch and ischemic stroke was not clearly recognized until the early 1990s when autopsy studies revealed a high prevalence of such lesions in particular in patients with cryptogenic strokes 7 . At that time examination of the aortic arch was not part of the routine echocardiographic examination. Protruding aortic atheromas (> 4-5 mm) have been found to be 3-9 times more common in stroke patients than in healthy controls. Later studies have...

Lifestyle factors

Stroke prevalence has been associated with individual lifestyle factors (e.g. smoking, exercise, body mass index (BMI), alcohol consumption) in several studies. Healthy lifestyle in general was considered in one large prospective cohort study of healthy women. In this study, healthy lifestyle, consisting of abstinence from smoking, low-normal body mass index, moderate alcohol consumption, regular exercise and healthy diet, was found to be associated with a reduction in ischemic stroke (RR 0.3...

Mechanisms of cerebral ischemia resulting from extracranial and intracranial large artery atherosclerosis

Artery-to-artery embolism is considered the most common mechanism of TIA and ischemic stroke due to large artery atherosclerosis. Thrombosis at the site of an atherosclerotic lesion is due to interplay between the vessel wall lesion, blood cells and plasma factors. Severe stenosis alters blood flow characteristics, and turbulence replaces laminar flow when the degree of stenosis exceeds about 70 . Platelets are activated when exposed to abnormal or denuded endothelium in the region of an...

Memory disturbances

It consists of five independent systems and involves three processes (encoding, storing consolidation and retrieval). Both depend on specific neural networks that may dissociate following a brain lesion. Classification of memory systems (Table 12.3) 9 depends upon three main vectors duration of memory traces (fractions of seconds, seconds or for life), content (explicit knowledge or motor routines) and access to consciousness (explicit or implicit). According...

Microbleeds

MRI visualizes acute and chronic hematomas, but also old, clinically non-apparent cerebral microbleeds that are not detected on CT. Microbleeds have a hypointense appearance on MRI and are usually smaller than 5-10 mm. Pathological studies have shown that microbleeds seen with GRE MRI usually correspond to hemosiderin-laden macrophages adjacent to small vessels and are indicative of previous extravasation of blood 35 . One review 36 included 53 case series studies involving 9073 participants,...

Middle cerebral artery MCA

The middle cerebral artery (MCA) is also designated the Sylvian artery, from Jacques Dubois, known as Jacobus Sylvius (1489-1555), a linguist and anatomist in Paris. The artery is subdivided into the M1 segment, from which start the deep perforating lenticulostriate arteries, the M2 segment, corresponding to the segment after the bifurcation into superior and inferior divisions, and the M3 segment, including the insular part. The M4 segments, the leptomeningeal arteries, arise from the M3...

Mortality

Both population- and hospital-based studies have shown that stroke patients with dementia after stroke have higher mortality rates than non-demented stroke patients, independently of age and co-morbidities 45 . The long-term mortality rate after stroke is 2-6-fold higher in patients with dementia, after adjustment for demographic factors, associated cardiac diseases, stroke severity and stroke recurrence 27, 46-48 . This increase in mortality rate in stroke patients with dementia may be due to...

Neuroradiology

PART A IMAGING OF ACUTE ISCHEMIC AND HEMORRHAGIC STROKE CT, PERFUSION CT, CT ANGIOGRAPHY NCCT can be performed in less than a minute with a helical CT scanner, and is considered sufficient to select patients for intravenous thrombolysis with iv-RTP within 4.5 hours, or endovascular treatment within 6 hours. It is a highly accurate method for identifying acute intracerebral hemorrhage and subarachnoid hemorrhage, but quite insensitive for detecting acute ischemia. The approximate sensitivity of...

Nonmodifiable risk factors of stroke

Age is probably the most important determinant of stroke the risk of stroke doubles for each successive decade after age 55 years 16, 17 . This is also true for ischemic stroke, while the age relation of intracerebral hemorrhage is less steep and the peak age of SAH incidence is around 45-55 years. Stroke is a common disease in both men and women, but it is more common in men within the age range of 45-84 years 18,19 . Racial or ethnic specific stroke risk is difficult to interpret. While...

Other antiplatelets

Whether or not other antiplatelet agents, with or without aspirin, confer additional vascular risk reduction has been extensively investigated. Evidence exists to support the use of the combination of aspirin and dipyridamole in secondary prevention 18 , and also that the antiplatelet agent clopidogrel is at least equivalent to aspirin and dipyridamole combined 19 . The combination of aspirin and clopidogrel has been shown to be of some value in patients with significant internal carotid artery...

Perfusionweighted imaging PWI and the mismatch concept

PWI maps are derived from the signal intensity change caused by the passage of contrast agent through the capillary bed and reflect several aspects of cerebral perfusion such as cerebral blood volume and flow and the mean transit time. Both the volume and the severity of the initial perfusion deficit are associated with the growth of the initial DWI lesion at follow-up imaging. The penumbra in acute stroke patients has been defined as brain tissue with loss of electrical activity and potential...

Personality changes

Persistent personality disturbances, defined as a change from the previous characteristic personality, are one of the most annoying behavioral disturbances found after stroke. For the caregiver these changes are hard to cope with and they are difficult to control pharmacologically. There are several types of personality changes in stroke patients aggressive, disinhi-bited, paranoid, labile and apathetic types. In the apathetic type the predominant feature is marked apathy and indifference....

Physical inactivity

Several prospective longitudinal population studies have shown the protective effect of regular physical activity for stroke in women and men. In a meta-analysis of 18 cohort and five case-control studies, physically highly active individuals had a lower risk of stroke and lower stroke mortality than those with low activity (RR 0.7 95 CI 0.7-0.8). Similarly, moderately active individuals had a lower risk of stroke, compared with those who were inactive (RR 0.8 95 CI 0.7-0.9) 51 . A similar...

Poststroke aphasia

Studies of glucose metabolism in aphasia after stroke have shown metabolic disturbances in the ipsilateral hemisphere caused by the lesion and contralateral hemisphere caused by functional deactivation (dia-schisis) (review in 26 ). In right-handed individuals with language dominance in the left hemisphere, the left temporo-parietal region, in particular the angular gyrus, supramarginal gyrus and lateral and transverse superior temporal gyrus are the most frequently and consistently impaired,...

Poststroke dementia

Stroke is an important risk factor for dementia and cognitive decline. According to the NINDAS-AIREN criteria, in order to make the diagnosis of post-stroke dementia (PSD) the patient has to be demented, with either historical, clinical or radiological evidence of cerebrovascular disease and the two disorders must be reasonably related 77 . On the other hand, according to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-4) 78 , vascular dementia is diagnosed by the...

Poststroke depression

Post-stroke depression is a prominent and persistent mood disturbance characterized by depressed mood or lack of interest or lack of pleasure (anhedonia) in all or almost all activities. Post-stroke depression has two subtypes with depressive features and similar to a major depressive episode. Figures related to the epidemiological features of post-stroke depression are highly variable, because they depend on the setting of the study, the time since stroke, the case mix and the criteria method...

Poststroke seizures

Epilepsy is one of the most common serious neurological disorders and is associated with numerous social and psychological consequences. Stroke is the most commonly identified etiology of secondary epilepsy and accounts for 30 of newly diagnosed seizures in patients older than 60 years 48 . Although recognized as a major cause of epilepsy in the elderly, many questions still arise regarding the epidemiology, treatment and outcome of post-stroke seizures. The common definition of epilepsy...

Prediction of irreversible tissue damage

The prediction of the portion of irreversibly damaged tissue within the ischemic area early after the stroke is of utmost importance for the efficiency of treatment. Meticulous analyses of CBF and CMRO2 data indicated that CMRO2 below 65 mmol (100gmin) predicted finally infarcted tissue, but also large portions with flow and oxygen utilization in the penumbra range were included in the final cortical-subcortical infarcts. Determination of oxygen utilization additionally requires arterial blood...

Prediction of stroke in patients with TIA

Ischemic stroke is often preceded by early symptoms, i.e. a transient ischemic attack (TIA) 36 . The risk of stroke after a TIA attack has been underestimated for many years due to issues in study designs 37, 38 . Hospital-based and population-based cohort studies have reported 7-day risks of stroke of up to 10 39-43 . Models with predictors for long-term risk of stroke after TIA or minor stroke have been developed 39-42, 44-46 . A substantial international variation exists as to how patients...

Prehospital care and referral

The essential building blocks for prehospital stroke care are the emergency medical service (EMS) organization consisting of an emergency response center (ERC), the EMS providers and the admitting stroke center, all of which should be involved in planning the prehospital critical pathway. The general emergency phone number 112 (in Finland) (911 in the United States) is the first link in the chain of survival and recovery for acute stroke patients. National stroke-awareness campaigns always...

Prevalence of dementia in stroke survivors

Prevalence studies include both dementia pre-existing to stroke and new-onset dementia occurring after stroke 5 . The prevalence of PSD ranges from 5.9 to 32 , depending on the mean age of the study population, exclusion or not of patients with aphasia or severe physical disability, mortality rates, delay between stroke onset and cognitive assessment, and criteria used for the diagnosis of dementia 5, 12 . Dementia is 3.5-5.8-fold more frequent in patients who have had a stroke than in...

Proportion of all strokes due to cardioembolic stroke

The proportion of strokes associated with cardio-embolic strokes increases sharply with age, mainly because of the epidemiological characteristics in the population of atrial fibrillation, the single most common major cardioembolic source. In some cases of cardioembolic stroke the association may be coincidental. This is certainly true for several of the minor cardioembolic sources (see below), for which findings from case-control studies show divergent results. As technology advances further...

QT prolongation

Prolongation of ventricular repolarization manifests as a prolongation of the QT interval on the electrocardiogram. QT prolongation may be associated with torsades de pointes tachycardia. Torsades de pointes are often self-limited and are associated with palpitations, dizziness or syncope. Degeneration into ventricular fibrillation and sudden cardiac death can occur. In addition to the congenital long QT syndrome many drugs, such as antiarrhythmic drugs class IA and III, antibiotics,...

Quality of life

Even if most patients remained independent, many of them lost their job or divorced during the 3 years after the ischemic stroke 7 . In the absence of a systematic evaluation it is difficult to identify the reason, but depression, fatigue, mild cognitive or behavioral changes or alteration in social cognition are likely explanations. Therefore ischemic strokes in young people are frequently associated with a decline in quality of life that is not explained by handicap 5, 7, 17 .

Realtime visualization of middle cerebral artery infarction

Perfusion harmonic imaging after SonoVue bolus injection can be used in patients with acute stroke. In the early phase of acute ischemic stroke, bolus imaging after SonoVue injection is useful for analyzing cerebral perfusion deficits at the patient's bedside. The ultrasound imaging data correlate well with the definite area of infarction and outcome after ischemic stroke. Ultrasound perfusion imaging with SonoVue has allowed measurements not only in ischemic stroke but also in intracerebral...

References

Kreisler A, Godefroy O, Delmaire C, Debachy B, Leclercq M, Pruvo JP, et al. The anatomy of aphasia revisited. Neurology 2000 4 1117-23. 2. Martin A. The representation of object concepts in the brain. Annu Rev Psychol 2007 58 25-45. 3. Saur D, Lange R, Baumgaertner A, Schraknepper V, Willmes K, Rijntjes M, et al. Dynamics of language reorganization after stroke. Brain 2006 129 1371-1384. 4. Plaut D, McClelland J, Seidenberg M, Patterson K. Understanding normal and impaired word reading. Psychol...

Secondary prevention

Albers Secondary prevention aims at preventing a stroke after a transient ischemic attack (TIA) or a recurrent stroke after a first stroke. About 80-85 of patients survive a first ischemic stroke 1, 2 . Of those between 8 and 15 suffer a recurrent stroke in the first year. Risk of stroke recurrence is highest in the first few weeks and declines over time 3-5 . The risk of recurrence depends on concomitant vascular diseases (CHD, PAD) and vascular risk factors...

Section I Etiology pathophysiology and imaging

1 Neuropathology and pathophysiology of stroke 1 Konstantin A. Hossmann and Wolf-Dieter Heiss 2 Common causes of ischemic stroke 28 (A) Imaging of acute ischemic and hemorrhagic stroke CT, perfusion CT, CT angiography 40 (B) Imaging of acute ischemic and hemorrhagic stroke MRI and MR angiography 43 Jens Fiehler (c) Functional imaging in acute stroke, recovery and rehabilitation 48 Wolf-Dieter Heiss 4 Ultrasound in acute ischemic stroke 58

Stroke characteristics

Most studies found that a more severe clinical deficit at onset is associated with a higher risk of dementia after stroke 5 . The risk of dementia and its severity are not influenced by the type of stroke (ischemic or hemorrhagic) 5 . However, differences in survival rates between stroke subtypes make the results difficult to interpret. In the Framingham study large-artery infarcts, lacunar infarcts and infarcts of unknown origin were associated with a higher risk of dementia after stroke 29 ....

Stroke unit care

A stroke unit is defined as an organized inpatient area that exclusively or nearly exclusively takes care of stroke patients and is managed by a multidisciplinary team of specialists who are knowledgeable about stroke care. The most distinctive features are a multi-disciplinary team specialized in the care of stroke patients (i.e. medical staff, nursing staff and therapists with expertise in stroke and rehabilitation), educational programs for the staff, involvement of care-givers, written care...

Takotsubo syndrome

Takotsubo syndrome (TTS), also known as apical ballooning, is a reversible neuromyocardial failure which resembles acute myocardial infarction clinically and electrophysiologically in patients with normal coronary arteries 63 . TTS is clinically characterized by sudden onset of anginal chest pain, dyspnea or syncope. Initially, the ECG shows ST elevation, which turns into negative T-waves a few hours or days later, which may persist for months 64, 65 . Reversible akinesia or hypokinesia affects...

The basilar artery BA

The BA lies on the ventral surface of the brainstem and vascularizes the pons, the mesencephalon and the middle and upper cerebellum through the AICA and SCA. Its territory can be subdivided into three parts on a ventro-dorsal level 11 . The anteromedial territory receives its blood supply from the paramedian arteries, the anterolateral territory from the short circumferential arteries (or anterolateral arteries) and the dorsolateral territory from the long circumferential arteries (or...

The scope of the problem

Stroke is the second leading cause of death worldwide in the adult population, the first being coronary heart disease 2 . Of note, stroke is an increasing problem in developing countries, 87 of stroke deaths occurring in low- and middle-income countries 2-4 . Stroke is the fourth leading cause of disease burden (as measured in disability-adjusted life years DALYs ) after heart disease, HIV AIDS and unipolar depressive disorders 2 . In the 1990s, it caused about 4.4 million deaths worldwide in...

The vascular origin of cerebrovascular disease

All cerebrovascular diseases (CVD) have their origin in the vessels supplying or draining the brain. Therefore, knowledge of pathological changes occurring in the vessels and in the blood is essential for understanding the pathophysiology of the various types of CVD and for the planning of efficient therapeutic strategies. Changes in the vessel wall lead to obstruction of blood flow, by interacting with blood constituents they may cause thrombosis and blockade of blood flow in this vessel. In...

The vertebral artery VA and the posterior inferior cerebellar artery PICA

The vertebral arteries give origin to two arteries before joining to form the basilar artery the anterior spinal artery, which supplies the medial medulla oblongata and the upper cervical cord, and the PICA, which supplies the inferior cerebellum and the dorsolateral medulla. The latter structure may also receive direct (long circumferential) branches from the vertebral artery. Three classic clinical syndromes are recognized in their territory the medial medullary stroke (or Dejerine syndrome)...

Thrombolysis

In respect of acute interventions, one of the most significant advances during the last two decades has been the introduction of intravenous thrombolysis as a standard therapy for a well-selected population of patients with acute ischemic stroke. At present, the only thrombolytic agent licensed in Europe for the treatment of ischemic stroke is recombinant-tissue plasminogen activator (rtPA), alteplase. The evidence for its use comes from six landmark clinical trials the Alteplase Thrombolysis...

Timing and intensity

Clinical studies indicate that an early start and high intensity of therapies are decisive for a favorable long-term outcome. On the basis of pathophysiological data, the first 3 weeks after stroke are considered as a particularly promising period in animal models active training leads to better functional recovery and sprouting, whereas inactivity results in additional loss of ability 12, 20, 23 . However, some experimental studies in rats show that very early (starting within 24 hours) and...

Translation of experimental concepts to clinical stroke

Experimental research has advanced our knowledge about brain physiology and the pathophysiology of brain disorders, but the transfer of this knowledge into clinical application is difficult and often lags behind. One of the reasons is the differences between the brains of experimental animals and man with respect to evolutionary state (non-gyrencephalic vs. gyrencephalic), anatomy (amount of gray vs. white matter), relative size, cellular density, blood supply and metabolism (see Table 1.1)...

Treatment ofspasticity

The treatment of spasticity requires mainly physiotherapy, nursing care, occupational therapy and in many cases orthotic management. Whereas spasticity as a consequence of a stroke might in many cases also have a certain beneficial compensatory aspect, it can also lead to increased disability, loss of function, pain, and hindered care, and also carries the risk of secondary complications. If physical treatment reaches a limit, in generalized symptoms of spasticity one might want to consider the...

Ultrasound diagnosis of intracranial stenosis and occlusion

Intracranial disease corresponds to approximately 8-10 of acute ischemic stroke, depending on gender and race. Diagnosis is frequently reached through Table 4.1. Highlights of the guidelines of the European Federation of NeurologicalSocieties 5 . Table 4.1. Highlights of the guidelines of the European Federation of NeurologicalSocieties 5 . Ultrasonography is the non-invasive screening technique indicated for the study of vessels involved in causing symptoms of carotid stenosis Transcranial...

Urinary tract infections

Urinary tract infections (UTI) are common infections post-stroke, since many patients have indwelling catheters in place, which convey a significant risk of infection. Asymptomatic occurrence of bacteria in the urine (bacteriuria) needs to be distinguished from a true infection. Signs of UTI include mild irritative symptoms, such as frequency and urgency, dysuria, fever, and severe systemic manifestations, such as bacteremia and sepsis. Microbiological examination of a urine specimen confirms...

Chronic infections and stroke

Atherosclerosis is a common disease and a major risk factor for stroke. Its etiology can largely be explained by the classic risk factors (age, gender, genetic predisposition, hypertension, diabetes, hypercholesterolemia, diet, smoking, low physical activity, etc.). Additionally, pathogens such as Helicobacter pylori, cytomegalovirus, herpes simplex virus and Chlamydia pneumoniae have been proposed to be associated with atherosclerosis. Most studies on the infectious etiology of atherosclerosis...

Motor rehabilitation

Motor impairment is the most common deficit in stroke, often resulting in reduced independence and mobility. Beside the concepts of physical, occupational and other therapies (see below) the following methods are aimed especially at motor recovery. Walking is an important objective in stroke rehabilitation, conventional gait training programs on the floor being routine practice. With the aim of enhancing the efficacy of gait training and also of easing the burden on the therapists, three groups...

Meningitis as a cause of stroke

Meningitis denotes the inflammation of the leptome-ninges, which consist of the pia mater and arachnoid mater. These layers ensheath the spinal cord and brain and confine the subarachnoidal space, which contains cerebrospinal fluid (CSF). Infection of the meninges by bacteria or fungi leads to an inflammatory response which causes the typical clinical symptoms, headache and nuchal rigidity. Depending on the time course, meningitis can be classified as acute or chronic. Acute bacterial...

Hypertension smoking alcohol cholesterol and drugs

Hypertension is the most common risk factor for spontaneous intracerebral hemorrhage and the frequency has been estimated to be between 70 and 80 . The causative role of hypertension is supported by the high frequency of left ventricular hypertrophy in autopsy of patients with ICH. The role of hypertension and the beneficial effect of antihypertensive treatment with regard to risk of ICH were verified in several large clinical trials. In the PROGRESS trial 21 the relative risk of ICH was...

Energy requirements of brain tissue

The energy demand of the nervous tissue is very high and therefore sufficient blood supply to the brain must be maintained consistently. A normal adult male's brain containing approx. 130 billion neurons (21.5 billion in the neocortex) 49 comprises only 2 of total body mass, yet consumes at rest approximately 20 of the body's total basal oxygen consumption supplied by 16 of the cardiac blood output. The brain's oxygen consumption is almost entirely for the oxidative metabolism of glucose, which...