Magnetic resonance angiography in childhood arterial brain infarcts: a comparative study with contrast angiography

Steno-occlusive Intracranial Large Vessel Arteriopathies in Childhood: A Pattern Oriented Approach to Neuroimaging Diagnosis

Intracranial steno-occlusive large vessel arteriopathies refer to abnormalities of the arterial wall that typically express luminal stenosis. Notably, some entities that can find themselves within this category may also express luminal dilation, and/or aneurysm formation as an alternative phenotype. Intracranial steno-occlusive large vessel arteriopathies are a leading cause of arterial ischemic stroke (AIS) in children, often progress, and can predispose to recurrent brain infarction. Intracranial arterial dissections account for a subset of cases expressing the focal cerebral arteriopathy (FCA) phenotype because the affected arterial segment, clinical presentation, and AIS patterns are very similar to the inflammatory subtype of FCA.

In Vivo Visualization and Quantification of Rat Laryngeal Blood Supply After Hydration Challenge

OBJECTIVES

Systemic dehydration decreases total body blood volume; however, hemodynamic alterations at the level of local organs, such as the larynx, remain unclear. Here we sought to quantify superior thyroid artery (STA) blood flow after dehydration and rehydration using in vivo magnetic resonance angiography (MRA) and ultrasound imaging in a rat model.

METHODS

Male Sprague-Dawley rats (N = 17) were included in this prospective, repeated measures design. Rats first underwent MRA to determine baseline STA cross-sectional area, followed by high-frequency in vivo ultrasound imaging to measure STA blood velocity at baseline. Next, rats were systemically dehydrated (water withholding), followed by rehydration (water ad-lib). Ultrasound imaging was repeated immediately after dehydration and following rehydration. The STA blood velocity and STA cross-sectional area were used to compute STA blood flow. Three rats served as temporal controls for ultrasound imaging. To determine if the challenges to hydration status affected the STA cross-sectional area, four rats underwent only MRA at baseline, dehydration, and rehydration.

RESULTS

Systemic dehydration resulted in 10.5% average body weight loss. Rehydration resulted in average body weight gain of 10.9%. Statistically significant reductions were observed in STA mean blood flow rate after dehydration. Rehydration reversed these changes to pre-dehydration levels. No significant differences were observed in STA cross-sectional area with dehydration or rehydration.

CONCLUSION

Systemic dehydration decreased blood flow in the superior thyroid artery. Rehydration restored blood flow in the STA. Change in hydration status did not alter the STA cross-sectional area. These preliminary findings demonstrate the feasibility of using ultrasound and MRA to quantify hemodynamic changes and visualize laryngeal blood vessels.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:779-785, 2024.

Neuroimaging in cerebellar ataxia in childhood: A review

Ataxia is one of the most common pediatric movement disorders and can be caused by a large number of congenital and acquired diseases affecting the cerebellum or the vestibular or sensory system. It is mainly characterized by gait abnormalities, dysmetria, intention tremor, dysdiadochokinesia, dysarthria, and nystagmus. In young children, ataxia may manifest as the inability or refusal to walk. The diagnostic approach begins with a careful clinical history including the temporal evolution of ataxia and the inquiry of additional symptoms, is followed by a meticulous physical examination, and, depending on the results, is complemented by laboratory assays, electroencephalography, nerve conduction velocity, lumbar puncture, toxicology screening, genetic testing, and neuroimaging. Neuroimaging plays a pivotal role in either providing the final diagnosis, narrowing the differential diagnosis, or planning targeted further workup. In this review, we will focus on the most common form of ataxia in childhood, cerebellar ataxia (CA). We will discuss and summarize the neuroimaging findings of either the most common or the most important causes of CA in childhood or present causes of pediatric CA with pathognomonic findings on MRI. The various pediatric CAs will be categorized and presented according to (a) the cause of ataxia (acquired/disruptive vs. inherited/genetic) and (b) the temporal evolution of symptoms (acute/subacute, chronic, progressive, nonprogressive, and recurrent). In addition, several illustrative cases with their key imaging findings will be presented.

Arteriopathy in pediatric stroke: an underestimated clinical entity

BACKGROUND

Pediatric arterial ischemic stroke (AIS), which was thought to be a rare disorder, is being increasingly recognized as an important cause of neurological morbidity, thanks to new advances in neuroimaging.

OBJECTIVE

The aim of this study was to review the main etiologies of stroke due to arteriopathy in children.

METHODS

Using a series of cases from our institution, we addressed its epidemiological aspects, physiopathology, imaging findings from CT, MR angiography, MR conventional sequences and MR DWI, and nuclear medicine findings.

RESULTS

Through discussion of the most recent classification for childhood AIS (Childhood AIS Standardized Classification and Diagnostic Evaluation, CASCADE), we propose a modified classification based on the anatomical site of disease, which includes vasculitis, varicella, arterial dissection, moyamoya, fibromuscular dysplasia, Takayasu's arteritis and genetic causes (such as ACTA-2 mutation, PHACE syndrome and ADA-2 deficiency). We have detailed each of these separately. Conclusions: Prompt recognition of AIS and thorough investigation for potential risk factors are crucial for a better outcome. In this scenario, neurovascular imaging plays an important role in diagnosing AIS and identifying children at high risk of recurrent stroke.

MRI detection of brain abnormality in sickle cell disease

Introduction: Over the past decades, neuroimaging studies have clarified that a significant proportion of patients with sickle cell disease (SCD) have functionally significant brain abnormalities. Clinically, structural magnetic resonance imaging (MRI) sequences (T2, FLAIR, diffusion-weighted imaging) have been used by radiologists to diagnose chronic and acute cerebral infarction (both overt and clinically silent), while magnetic resonance angiography and venography have been used to diagnose arteriopathy and venous thrombosis. In research settings, imaging scientists are increasingly applying quantitative techniques to shine further light on underlying mechanisms.Areas covered: From a June 2020 PubMed search of 'magnetic' or 'MRI' and 'sickle' over the previous 5 years, we selected manuscripts on T1-based morphometric analysis, diffusion tensor imaging, arterial spin labeling, T2-oximetry, quantitative susceptibility, and connectivity.Expert Opinion: Quantitative MRI techniques are identifying structural and hemodynamic biomarkers associated with risk of neurological and neurocognitive complications. A growing body of evidence suggests that these biomarkers are sensitive to change with treatments, such as blood transfusion and hydroxyurea, indicating that they may hold promise as endpoints in future randomized clinical trials of novel approaches including hemoglobin F upregulation, reduction of polymerization, and gene therapy. With further validation, such techniques may eventually also improve neurological and neurocognitive risk stratification in this vulnerable population.

A model of silent brain infarction induced by endovascular intervention with balloon in cynomolgus macaques: A pilot study

Silent brain infarction is a special type of cerebral infarction, which can be detected by MRI or CT. The most patients with silent brain infarction show no symptoms, but some have mild depression, vascular dementia and other symptoms that are easily overlooked. Silent brain infarction is one of the risk factors for symptomatic cerebral infarction, it can develop into symptomatic cerebral infarction placing a heavy burden on families and society. Therefore, it's prevention and treatment should be as important as symptomatic cerebral infarction. However, the pathogenesis of silent brain infarction has not been elucidated. Studies have shown that silent brain infarction models have been established in rats and mice. But compared with other animals, non-human primates are more similar to humans in neuroanatomical structure and clinical characteristics. Therefore, this study is the first time to explore the silent brain infarction model in cynomolgus macaques. In this study, a model of silent brain infarction was established by endovascular intervention using balloon occlusion at the end of internal carotid artery for 45 min, which can lay a foundation for the future research on the pathological mechanism of silent brain infarction.

Dijabetesna ketoacidoza kod bolesnika sa cerebrovaskularnim insultom - uzroci, mehanizmi, dijagnostika i naše smernice za terapiju

Although cerebrovascular disease may be a well recognised trigger for diabetic ketoacidosis (DKA), literature data on the precise mechanisms, characteristics, or treatment guidelines are rare. The risk of developing an ischemic stroke is doubled in adults with diabetes compared to people with normal glucose metabolism. It is important to point out that even children with DKA have a significantly increased risk of cerebrovascular insult and that they can have a stroke with a frequency of about 10%. Given the significant overlap of symptoms between these two diseases, it can be assumed that attributing DKA symptoms as a manifestation of stroke is not uncommon, especially in elderly and less communicative patients. In addition, pH, bicarbonate concentration, and anion gap are not routinely measured in all diabetics suffering from stroke, at least not in secondary health institutions.Children who develop cerebrovascular stroke during DKA often at the beginning have a preserved consciousness or only mild confusion or lethargy. After a few hours, with the institution of therapy, however, loss of consciousness may occur accompanied by signs of increased intracranial pressure. It was previously thought that the cause was too fast fluid replacement. Recent data suggest that reperfusion injury may be a more likely mechanism. Although most of these studies relate to younger individuals with ketoacidosis, it is clear that at least some of them may be operative in adult DKA. Literature therapeutic guidelines for adult diabetics with stroke-related diabetic ketoacidosis are almost lacking, although it is clear that they could not be the same as those utilised in population with normal glucose metabolism. In this paper, we have tried to define our treatment guidelines for these particular patients.

A rare cause of ischemic stroke in childhood: spontaneous long segment intracranial dissection

Craniocervical arterial dissection is an important cause of arterial ischemic stroke in children. Recognition of dissections is of particular importance both in determining the risk of recurrence and in bringing about different treatment alternatives. We report a 10-year-old girl who presented with acute ischemic stroke due to spontaneous long segment dissection involving the parasellar internal carotid artery up to the distal M1 portion of the middle cerebral artery. Three-dimensional digital subtraction angiography with flat panel detector revealed the presence of major vessels originating from both true and false lumens and had a critical role in the treatment decision of the case.

Selection of preclinical models to evaluate intranasal brain cooling for acute ischemic stroke

Stroke accounts for a large proportion of global mortality and morbidity. Selective hypothermia, via intranasal cooling devices, is a promising intervention in acute ischemic stroke. However, prior to large clinical trials, preclinical studies in large animal models of ischemic stroke are needed to assess the efficacy, safety, and feasibility of intranasal cooling for selective hypothermia as a neuroprotective strategy. Here, we review the available scientific literature for evidence supporting selective hypothermia and make recommendations of a preclinical, large, animal-based, ischemic stroke model that has the greatest potential for evaluating intranasal cooling for selective hypothermia and neuroprotection. We conclude that among large animal models of focal ischemic stroke including pigs, sheep, dogs, and nonhuman primates (NHPs), cynomolgus macaques have nasal anatomy, nasal vasculature, neuroanatomy, and cerebrovasculature that are most similar to those of humans. Moreover, middle cerebral artery stroke in cynomolgus macaques produces functional and behavioral deficits that are quantifiable to a greater degree of precision and detail than those that can be revealed through available assessments for other large animals. These NHPs are also amenable to extensive neuroimaging studies as a means of monitoring stroke evolution and evaluating infarct size. Hence, we suggest that cynomolgus macaques are best suited to assess the safety and efficacy of intranasal selective hypothermia through an evaluation of hyperacute diffusion-weighted imaging and subsequent investigation of chronic functional recovery, prior to randomized clinical trials in humans.

Acute ischemic stroke in a 7-month-old infant, risk factors, and diagnosis peculiarities: A case report

INTRODUCTION

Ischemic stroke is an extremely rare disorder in children. The timely diagnosis is essential for the outcome of these children, but unfortunately, delays in diagnosis occur frequently.

PATIENT CONCERNS

We report the case of a 7-month-old infant admitted in our clinic for limited movements of the superior and inferior right limbs whose onset was 27 hours before with repeated clonic movements of the right hand associated with the same manifestations in the right oral commissure lasting approximately 10 seconds.

DIAGNOSIS

The laboratory tests revealed high D-dimers, and positive IgG anti-cardiolipin and anti-beta2 glycoproteins I antibodies, whereas the genetic profile for thrombophilia revealed heterozygote mutation in MTHFR C677T and A1298C genes. Brain imaging established the diagnosis of left frontal ischemic stroke, frontal ischemic stroke, hypoplasia of internal carotid artery, and agenesia of segment M1 of median cerebral artery and segment A1 of left anterior cerebral artery.

INTERVENTION

We administered low-molecular-weight heparin, antiplatelet therapy along with vasodilators and depletive treatment, wide-spectrum antibiotics, and anticonvulsant therapy.

OUTCOME

The neurological deficit was greatly improved, especially in the inferior limb after 6 month from the incident of stroke, and all laboratory parameters were within normal limits including the antibodies mentioned above.

CONCLUSION

Cerebral vascular malformation, excessive weight, and altered lipid profiles contributed to the development of acute ischemic stroke in our patient.

Imaging of Childhood Inflammatory Brain Diseases

Brain has been considered as an immune-privileged site for centuries owing to the presence of blood-brain barrier, absent lymphatic drainage, and antigen-presenting cells. However, the present prevailing concept is of immune surveillance where brain is continuously surveyed by immune cells. However, the presence of immune cells in central nervous system (CNS) brings the risk of inflammation and autoimmunity involving both T and B cell mediated pathways. These mechanisms form the underlying pathology in a wide spectrum of pediatric CNS diseases manifesting as acquired neurological deficits. Overlapping, heterogenous, and ambiguous clinical features often delays the diagnosis. Although not always pathognomonic, magnetic resonance imaging can be an important biomarker leading to early diagnosis, prognostication, and systematic follow-up pf these diseases. This review describes the spectrum of different pediatric inflammatory disorders and their pertinent imaging features illustrated with clinical examples.

Epidemiology, Clinical Presentation, and Prognosis of Posterior Circulation Ischemic Stroke in Children

BACKGROUND

Anterior and posterior circulation strokes are often different in terms of presentation and recurrence risk, but there are few studies that focused on posterior circulation stroke.

METHODS

We performed a longitudinal retrospective study of children, birth to 18 years, with posterior circulation ischemic stroke at the Children's Hospital Winnipeg from January 1992 to December 2012. Clinical and radiological features and outcomes were collected using standardized tools.

RESULTS

Of the 158 children with arterial ischemic stroke, 23 (14.5%) children, 21 non-neonates, and 11 males were identified. For posterior circulation ischemic stroke, mean crude incidence of 0.38 and crude mortality rate of 0.11 per 100,000 person-years was estimated. The crude total period prevalence rate for the study period was estimated as 8.1 per 100,000 children. Nonspecific symptoms before stroke presentation were present in 38% and impaired consciousness in 71%. Identifiable risk factors were present in two thirds: vasculopathy 24%, infection 19%, trauma 14%, and congenital heart disease 9.5%. Average Pediatric National Institutes of Health Stroke Scale score at presentation was 11. Poor outcome was noted in 45%. Outcome did not change significantly between 12 and 24 months. Aboriginal ethnicity (P = 0.01), high Pediatric National Institutes of Health Stroke Scale score (P = 0.001), bilateral infarction (P = 0.001), and large caliber artery territory infarction (P = 0.02) predicted poor outcome.

CONCLUSIONS

Our hospital-based incidence and outcome data provide valuable information to help direct treatment strategies and prognosticate children with posterior circulation ischemic stroke. Our study calls for close observation and early management of children with posterior circulation stroke, in particular with aboriginal ancestry and bilateral and large artery territory infarction.

Imaging in Pediatric Demyelinating and Inflammatory Diseases of Brain- Part 2

Imaging plays an important role in diagnosis, management, prognostication and follow up of pediatric demyelinating and inflammatory diseases of brain and forms an integral part of the diagnostic criteria. This article reviews the spectrum of aquaporinopathies with an in-depth discussion on present criteria and differentiation from other demyelinating diseases with clinical vignettes for illustration; the latter part of article deals with the spectrum of CNS vasculitis.

Presumed Perinatal Stroke: Risk Factors, Clinical and Radiological Findings

It is unknown why some infants with perinatal stroke present clinical symptoms late during infancy and will be identified as infants with presumed perinatal stroke. The risk factors and clinical and radiological data of 42 infants with presumed perinatal stroke (69% with periventricular venous infarction and 31% with arterial ischemic stroke) from the Estonian Pediatric Stroke Database were reviewed. Children with presumed perinatal stroke were born at term in 95% of the cases and had had no risk factors during pregnancy in 43% of the cases. Children with periventricular venous infarction were born significantly more often (82%) vaginally (P = .0213) compared to children with arterial stroke (42%); nor did they require resuscitation (P = .0212) or had any neurological symptoms after birth (P = .0249). Periventricular venous infarction is the most common type of lesion among infants with the presumed perinatal stroke. Data suggest that the disease is of prenatal origin.

Strokes in children: a systematic review

CONTEXT

Pediatric strokes lead to significant morbidity and mortality. To date, no systematic review has been available to guide the initial diagnostic approach to pediatric stroke.

OBJECTIVE

The objective of this review was to elucidate the current data regarding etiologies of stroke in children and then develop an initial diagnostic evaluation for the pediatric patient presenting to the emergency department with a stroke.

DATA SOURCE

Using the PubMed engine, the MEDLINE database was searched using the Preferred Reporting Items in Systematic Reviews and Meta-Analyses guidelines.

STUDY SELECTION

The inclusion and exclusion criteria were established a priori. Studies must have extractable data regarding first strokes in pediatric patients with clear diagnostic categories.

DATA EXTRACTION

A standardized tool was developed to extract demographic data and stroke etiologies.

RESULTS

Twelve studies were found that met the inclusion criteria. From these studies, a total of 1455 children aged between 21 days and 20 years were available to assess the etiologies of stroke.

CONCLUSIONS

In pediatric patients, the etiologies of stroke are varied and differ for children with ischemic stroke versus hemorrhagic stroke. With the present systematic review, a guide to the initial evaluation of stroke is presented.

Childhood central nervous system vasculitis

Inflammatory brain diseases in childhood are underrecognized and lead to devastating yet potentially reversible deficits. New-onset neurologic or psychiatric deficits in previously healthy children mandate an evaluation for an underlying inflammatory brain disease. Distinct disease entities, such as central nervous system (CNS) vasculitis, are now being increasingly reported in children. Clinical symptoms, initial laboratory test, and neuroimaging studies help to differentiate between different causes; however, more invasive tests, such as lumbar puncture, conventional angiography, and/or brain biopsy, are usually necessary before the start of treatment. This article focuses on childhood CNS vasculitis.

Craniocervical arterial dissection in children: diagnosis and treatment

OPINION STATEMENT

Diagnosis of craniocervical arterial dissection (CCAD) in children begins with a careful history and physical in a child with a transient ischemic attack (TIA) or arterial ischemic stroke (AIS). The extent of radiologic evaluation for suspected CCAD is based upon careful consideration of the risks associated with the best imaging techniques, weighed against the benefits of enhanced vascular imaging with better diagnostic sensitivity. Although conventional angiography (CA) and CT angiography (CTA) have a higher sensitivity than magnetic resonance angiography (MRA), they are accompanied by risks: for CA, femoral hematoma, femoral arterial pseudoaneurysm, recurrent AIS, and radiation exposure; for CTA, radiation. For children (non-neonates) with suspected CCAD, MRI with MRA is recommended as the first-line imaging study. MRI usually includes diffusion-weighted, FLAIR, and T1 images of the brain, and T1 or T2 fat-saturation axial imaging through the neck. MRA should include 3D time-of-flight MRA of the head and neck (from the aortic arch through the circle of Willis). Contrast-enhanced MRA should be highly considered in neck imaging. If MRI/MRA is equivocal, CCAD is strongly suspected but not detected on MRI/MRA (especially in the posterior circulation), or the child has recurrent events, additional imaging of the craniocervical vasculature is likely warranted. Individual clinical circumstances warrant careful, case-by-case consideration. Treatment of CCAD in children is challenging and differs for intracranial and extracranial dissections. In extracranial CCAD, we most commonly use anticoagulation for 6 weeks to 6 months in patients with TIA or AIS. Typically, unfractionated heparin is used in the acutely ill patient at heightened risk for bleeding (because of its short half-life), whereas low-molecular-weight heparin (LMWH) or warfarin are reserved for the stable patient. If the history is suspicious for dissection (head and neck trauma, recent cervical chiropractic manipulation, recent car accident, or neck pain), we consider treatment for dissection even with normal MRI/MRA. For patients with CCAD with a stroke size greater than one third to one half of the middle cerebral artery territory (or other bleeding risk factors) and extracranial CCAD, in whom there is concern about heightened risk for hemorrhagic conversion, we commonly use aspirin therapy during the acute phase. Regardless of their treatment in the initial weeks to months, we subsequently treat all patients with aspirin for 1 year after their event, and sometimes longer if they have other risk factors. Interventional techniques, such as extracranial cerebral arterial stent placement or selective occlusion, are understudied in children. Interventional techniques are typically reserved for patients who fail aggressive medical management and have recurrent TIA or AIS. The diagnosis and treatment of intracranial dissection is extraordinarily challenging in children, in whom inflammatory intracranial arteriopathies are common. When intracranial arteriopathy is clearly associated with dissection, the clinician should look for the presence of subarachnoid hemorrhage and/or dissecting aneurysm. Treatment decisions should be made by a multidisciplinary pediatric stroke team, given the lack of data in this area. Intracranial cerebral artery stent placement carries high risk and is not recommended for intracranial CCAD in children. Most importantly, we educate all children with CCAD and their parents about the paucity of evidence in the treatment of this disease, the risks of enhanced imaging techniques such as CTA or CA, and the challenges involved in weighing the risks of aggressive therapies and interventions against the costs of unclear diagnosis and potentially ineffective treatments. We also educate our patients with CCAD about the signs and symptoms of recurrence and the importance of emergent evaluation.

American childhood football as a possible risk factor for cerebral infarction

Three adolescent football players who had ischemic stroke associated with football practice and play are described. The literature on stroke associated with childhood sports and football in particular is reviewed, and the multiple mechanisms by which football can contribute to ischemic stroke are discussed.

The role of imaging studies for evaluation of stroke in children

Stroke is a major cause of morbidity and mortality in children and long-term neurological deficits. Although cerebrovascular disorders occur less often in children than in adults, recognition of stroke in children has probably increased because of the widespread application of noninvasive diagnostic studies such as magnetic resonance imaging and computed tomography.Computed tomography (CT) should be the first imaging choice in the emergency setting when stroke is suspected. It will show the presence of hemorrhage (eg, bleeding from arteriovenous malformation). It is often normal within the first hours in arterial ischemic stroke. As in adults, magnetic resonance imaging is the neuroimaging modality to confirm the clinical diagnosis of ischemic stroke. In children, however, magnetic resonance imaging requires sedation and may not be as readily available as CT. Perfusion imaging demonstrates flow within the brain and can detect areas that are at risk of ischemia; however, further studies in the pediatric population need to be validated for this technique in children. Angiography detects arterial disease (eg, aneurysm); however, its use has been largely superseded by better magnetic resonance angiography, which is sensitive enough to visualize lesions in the proximal anterior cerebral artery, middle cerebral artery, and distal internal carotid artery (ICA). Magnetic resonance imaging using diffusion- weighted imaging is the most versatile and sensitive imaging technique for identifying ischemic lesions. In the future, we need to identify the pediatric patient presenting to the emergency department with an acute stroke and develop a pathway for the use of particular imaging techniques (eg, CT vs magnetic resonance imaging).

Ischemic stroke in infants and children: practical management in emergency

Stroke is a rare disease in children, with an estimated incidence 13/100000 and a significant impact on morbidity and mortality. Clinical presentation and risk factors, present in almost half of pediatric patients, are not the same as in adults. The diagnosis of stroke in children is often delayed because signs and symptoms can be subtle and nonspecific. History and clinical examination should exclude underlying diseases or predisposing factors. Neuroimaging is crucial in defining diagnosis. Other tests might be necessary, according to the clinical picture. We present here the most recent practical directions on how to diagnose and manage arterial stroke in children, according to different international guidelines on the subject.

Incidence of vasculopathy in children with hypothalamic/chiasmatic gliomas treated with brachytherapy

INTRODUCTION

External brain irradiation in children can cause cognitive decline, endocrine dysfunctions and second malignancies. A rare complication is cerebral vasculopathy, which occurs most often in patients with neurofibromatosis type 1. Interstitial radiotherapy using transient Iodine-125 implants is a radiotherapy option, called brachytherapy, offering excellent survival rates, but little is known on treatment-related morbidity, especially long time vascular changes.

PATIENTS AND METHODS

Thirteen children with low-grade hypothalamic gliomas, four of them with neurofibromatosis type 1, were diagnosed and treated at the University Hospital Freiburg, Germany. They belong to a larger group of 44 children with suprasellar low-grade gliomas, treated with transient Iodine-125 seeds and include those who attended all routine follow-up examinations in Freiburg. After written informed consent from the parents or caregivers all patients underwent magnetic resonance imaging with angiographic techniques in 2001, 3 to 13 years after treatment.

RESULTS AND DISCUSSION

Six out of 13 revealed cerebral vasculopathies, only one of them revealed symptoms of intermittent cerebral ischemia. Neurofibromatosis type 1 was present in one affected patient. The aetiology of the cerebral vascular changes is not fully understood so far. Tumour encasement, surgical damage and brachytherapy may contribute as a single risk factor or in combination. To get more information, we recommend MRA for artery vasculopathy at follow-up in all patients with suprasellar brain tumours irrespectively to their former treatment or presence of cerebrovascular symptoms.

Pediatric stroke: clinical findings and radiological approach

This paper focuses on radiological approach in pediatric stroke including both ischemic stroke (Arterial Ischemic Stroke and Cerebral Sinovenous Thrombosis) and hemorrhagic stroke. Etiopathology and main clinical findings are examined as well. Magnetic Resonance Imaging could be considered as the first-choice diagnostic exam, offering a complete diagnostic set of information both in the discrimination between ischemic/hemorrhagic stroke and in the identification of underlying causes. In addition, Magnetic Resonance vascular techniques supply further information about cerebral arterial and venous circulation. Computed Tomography, for its limits and radiation exposure, should be used only when Magnetic Resonance is not available and on unstable patients.

Diabetic ketoacidosis-associated stroke in children and youth

Diabetic ketoacidosis (DKA) is a state of severe insulin deficiency, either absolute or relative, resulting in hyperglycemia and ketonemia. Although possibly underappreciated, up to 10% of cases of intracerebral complications associated with an episode of DKA, and/or its treatment, in children and youth are due to hemorrhage or ischemic brain infarction. Systemic inflammation is present in DKA, with resultant vascular endothelial perturbation that may result in coagulopathy and increased hemorrhagic risk. Thrombotic risk during DKA is elevated by abnormalities in coagulation factors, platelet activation, blood volume and flow, and vascular reactivity. DKA-associated cerebral edema may also predispose to ischemic injury and hemorrhage, though cases of stroke without concomitant cerebral edema have been identified. We review the current literature regarding the pathogenesis of stroke during an episode of DKA in children and youth.

Treatment challenges in pediatric stroke patients

Aim. In this study we presented our experience of 18 years on the etiology, risk factors, prophylactic and acute treatment, the effect of treatment to recurrence rate of patients with stroke. Methods. The population included 108 patients who had been treated for stroke at Pediatric Neurology Department of Ankara University with the diagnosis of arterial ischemic stroke and sinovenous thrombosis between January 1992 and August 2010. Forty-one girls (38%) and 67 boys (62%) with mean symptom age 3.1 ± 4.04 years, (0–18 years old) were followed up with a mean period of 4.9 ± 3.78 years (0–17 years). Results. 30 patients had no risk factors, 34 patients had only one risk factor and 44 patients had multiple risk factors. Recurrence was seen in three patients. There was no any statistical correlation between the recurrence of stroke and the existence of risk factors (P = .961). Seventeen patients received prophylactic treatment; 2 of them without any risk factors, 3 had one risk factor, 12 patients, who constituted the majority of our patients, had multiple risk factors (P = .024). Conclusion. With this study we showed that the right prophylaxis for right patients reduces the rate of recurrence.

Childhood Posterior Circulation Arterial Ischemic Stroke

Background and Purpose— Limited data exist on childhood posterior circulation arterial ischemic stroke (PCAIS). We describe clinical and radiological features of childhood PCAIS to determine whether there are differences in infarct topography, vascular abnormalities, risk factors, and stroke subtypes when compared to adults.

Methods— Children with radiologically confirmed PCAIS were prospectively identified from August 2002 to February 2008. Infarcts were divided into proximal, middle, and distal posterior circulation segments utilizing an adult topographical classification system. Vascular abnormalities were described in terms of location, severity, and evolution over time. A pediatric modification of the TOAST classification system was used to define stroke subtypes.

Results— Twenty seven (37%) of 73 children recruited to our registry had 34 radiologically confirmed PCAIS events. Infarct location was distal (25), middle (2), proximal (1), and multiple segments (6). Fourteen events were associated with single infarcts and 20 were associated with multiple infarcts. Magnetic resonance angiography was abnormal in 16 of 25 children with PCAIS at presentation with stenosis (8) or occlusion (8). Vascular lesions progressed (5), transiently worsened before stabilizing (2), remained stable or improved (8), or normalized (1) over 12 months. Stroke subtypes included nonprogressive steno-occlusive cerebral arteriopathy (9), cardioembolic (4), dissection (3), Moyamoya syndrome (3), other determined (4), probable (1), and undetermined etiology (3). Fifty-two percent of children had recurrent posterior (6) or anterior (8) strokes.

Conclusions— Nonprogressive arteriopathies are the most common cause of childhood PCAIS, usually affecting distal segments. Atherosclerosis-related risk factors do not play an important role in stroke causation. PCAIS is frequently associated with recurrent events.

Predictive value of clinical and radiological findings in inflicted traumatic brain injury

AIMS

The aim of this study is to evaluate the value of early radiological investigations in predicting the long-term neurodevelopmental outcome of infants with inflicted traumatic brain injury (ITBI).

METHODS

Clinical and radiological investigations of 24 infants with ITBI were performed during the acute phase of injury (1-3 days), and during the early (4 days up to 3 months) and late (>9 months) postinjury phases. The clinical outcome in survivors (n = 22) was based on the Rankin Disability Scale and the Glasgow Outcome Score.

RESULTS

Five out of 24 infants (21%) had a poor neurodevelopmental outcome (death and severe disability), 17 infants (71%) had different developmental problems and 2 infants were normal at the mean age of 62 (54-70) (95% CI) months. A low initial Glasgow Coma Scale score of 8 or below [p < 0.05, OR 13.0 (1.3-133.3)], the development of brain oedema [p < 0.005, OR 13.0 (1.6-773)], focal changes in the basal ganglia during the acute phase [p < 0.01, OR 45 (2.1-937.3)], the development of new intracerebral focal changes early postinjury [p < 0.05, OR 24.1(1.0-559.1)], a decrease in white matter [p < 0.01, OR 33 (1.37-793.4)] and the development of severe atrophy before 3 months postinjury [p < 0.05, OR 24 (11.0-559.1)] were significantly correlated with a poor neurodevelopmental outcome.

CONCLUSIONS

Early clinical and radiological findings in ITBI are of prognostic value for neurodevelopmental outcome.

Diagnosis and management of pediatric arterial ischemic stroke

Pediatric stroke is among the top 10 causes of death in children and an important cause of chronic morbidity, with an incidence of 3.3/100,000 children/year. Risk factors associated with stroke in children include cardiac diseases, hematologic and vascular disorders, and infection. Clinical presentation varies depending on age, underlying cause, and stroke location. Antithrombotics and anticoagulants are used in the treatment of pediatric stroke; however, there are no established guidelines for the use of these agents in children. In this article we review the cause, pathophysiology, clinical presentation, diagnosis, acute management, secondary prevention, and outcome of children with stroke. The approach to patients with sickle cell disease and Moyamoya disease is also discussed. Up to date studies to determine the optimal acute treatment of childhood stroke and secondary prevention and risk factor modification are critically needed.

Epidemiology of childhood stroke in Estonia

We investigated the incidence and 30-day case-fatality of childhood stroke in Estonia, and clinical signs and risk factors of childhood stroke. A retrospective (1995-2003) and prospective study (2004-2006) of childhood stroke (arterial ischemic, hemorrhagic, and sinovenous thrombosis) and transient ischemic attack was conducted. Stroke-incidence calculation was based on the prospective study. Clinical diagnoses of stroke were confirmed by neuroradiology. The incidence rate of childhood stroke in Estonia was 2.73/100,000 person-years for children aged 30 days to 18 years: 1.61/100,000 for arterial ischemic stroke, 0.87/100,000 for hemorrhagic stroke, 0.25/100,000 for sinovenous thrombosis, and 0.37/100,000 for transient ischemic attack. No arterial ischemic stroke patients died within 30 days, but case-fatality for intracerebral hemorrhage was 46%. Focal signs occurred in 100% of arterial ischemic strokes and 64% of intracerebral hemorrhage cases. Risk factors were identified in 35/48 (73%) children with cerebrovascular attacks. Six children with arterial ischemic stroke (6/24, 25%) manifested more than one risk factor. The incidence rate of childhood stroke in Estonia is similar to that in earlier data.

Magnetic resonance imaging in neonatal stroke

Neonatal stroke occurs in 1 in 2300-5000 live births, the incidence of which is lower than that in adults, but still higher than that in childhood. The higher incidence of perinatal stroke in preterm and term infants compared to stroke in childhood may be partly explained by higher detection rates using routine fetal ultrasound and postnatal cranial sonography. In addition, there is greater availability of magnetic resonance imaging (MRI) for neuroimaging in preterm and full-term infants, which is due in part to the availability of MR-compatible incubators and MR systems at or near the neonatal intensive care unit. In addition, the wide range of MR techniques, such as T2-, diffusion- and susceptibility-weighted imaging allows improved visualization and quantification of neonatal stroke or hypoxic-ischemic injury. This chapter reviews the MR neuroimaging modalities that actually assist the clinician in the detection of neonatal stroke.

Low detection rate of craniocervical arterial dissection in children using time-of-flight magnetic resonance angiography: causes and strategies to improve diagnosis

Craniocervical arterial dissection is a frequent cause of childhood arterial ischemic stroke requiring prompt diagnosis and treatment. However, there is no universal guideline for diagnostic cerebrovascular imaging in children. We assessed the role of time-of-flight magnetic resonance angiography in diagnosing craniocervical arterial dissection. We included children (1 month to 18 years) with craniocervical arterial dissection and ischemic stroke from January 1998 to June 2007. Institutional protocol required magnetic resonance imaging (MRI)/ magnetic resonance angiography for all ischemic stroke cases and conventional cerebral angiography if magnetic resonance angiography showed any arteriopathy. Among 233 ischemic stroke cases, craniocervical arterial dissection was diagnosed in 13 patients (5.6%; 10 males), with a mean age of 7.5 years. Initial time-of-flight magnetic resonance angiography missed dissection in 8 patients (61.5%) because the neck vessels were not scanned (n = 2), of suboptimal technique (n = 3), and of diagnostic error (n = 3). T1 fat-saturated MRI and contrast-enhanced magnetic resonance angiography were not performed in 12 patients. If suspicion for arterial dissection is high, T1 fat-saturated neck imaging and contrast-enhanced magnetic resonance angiography should be considered to maximize detection.

Radiological strategy in acute stroke in children

The aim of the study was to estimate the preponderance of patterns of pediatric stroke, ischemic or hemorrhagic, their etiologies and the correct diagnostic protocol for acute management. Forty-one consecutive pediatric patients (age range 5-16 years) with an acute stroke observed in acute phase during a 10-year period, were retrospectively evaluated. Twenty-three patients underwent magnetic resonance imaging (MRI), 3 cases were studied by computed tomography (CT) without MRI, and 15 underwent both CT and MRI studies. In 9 cases, intra-arterial digital subtraction angiography (IADSA) was performed after non-invasive preliminary assessment. Seventeen hemorrhagic (41%) and 24 ischemic (59%) strokes were found. Among hemorrhagic forms, 5 cases were due to arteriovenous malformation (AVM), 7 to cavernoma, and 2 to aneurysm. Among ischemic forms, 2 were due to sickle-cell disease, 1 to hyperomocysteinemia, 1 to moyamoya syndrome, 1 to pseudoxantoma elasticum, 3 to prothrombotic state, 1 to Fabry's disease, 1 concomitant with CO intoxication, 5 to venous sinus thrombosis, and 4 to cardio-embolic state. Etiology remains unknown in 8 cases (20.5%). This study shows a moderate prevalence of ischemic over hemorrhagic strokes. Moreover, personal experience suggests that MRI is always more informative than CT and in selected cases should be the first-choice examination in the acute phase.

MRI in paediatric hypoxic-ischemic disease, metabolic disorders and malformations-a review

MRI has become the most important modality in paediatric neuroimaging. It provides an excellent anatomical overview with good spatial and temporal resolution, allows investigations of the blood vessels, and - using technologies such as diffusion-weighted imaging and magnetic resonance spectroscopy - it allows quick and exact differentiation of ischemic, hypoxic, inflammatory, oncologic, traumatic and metabolic diseases. This review presents an overview of brain MRI in infants and children with suspected hypoxic-ischemic disease, metabolic disorders or (vascular) malformations, illustrating these issues by some MRI findings in selected important conditions and discussing some major clinical and pathophysiological aspects important for imaging.

Management of stroke in infants and children: a scientific statement from a Special Writing Group of the American Heart Association Stroke Council and the Council on Cardiovascular Disease in the Young

PURPOSE

The purpose of this statement is to review the literature on childhood stroke and to provide recommendations for optimal diagnosis and treatment. This statement is intended for physicians who are responsible for diagnosing and treating infants, children, and adolescents with cerebrovascular disease.

METHODS

The Writing Group members were appointed by the American Heart Association Stroke Council's Scientific Statement Oversight Committee. The panel included members with several different areas of expertise. Each of the panel's recommendations was weighted by applying the American Heart Association Stroke Council's Levels of Evidence grading algorithm. After being reviewed by panel members, the manuscript was reviewed by 4 expert peer reviewers and by members of the Stroke Council Leadership Committee and was approved by the American Heart Association Science Advisory and Coordinating Committee. We anticipate that this statement will need to be updated in 4 years.

RESULTS

Evidence-based recommendations are provided for the prevention of ischemic stroke caused by sickle cell disease, moyamoya disease, cervicocephalic arterial dissection, and cardiogenic embolism. Recommendations on the evaluation and management of hemorrhagic stroke also are provided. Protocols for dosing of heparin and warfarin in children are suggested. Also included are recommendations on the evaluation and management of perinatal stroke and cerebral sinovenous thrombosis in children.

Recurrent intracerebral hemorrhage from a cerebral arteriovenous malformation undetected by repeated noninvasive neuroimaging in a 4-year-old boy. Case report

The authors report the case of a 4-year-old boy with a spontaneous intracerebral hemorrhage (ICH) related to an arteriovenous malformation (AVM) that was not found with good-quality magnetic resonance (MR) imaging and MR angiography. Both modalities were used serially in the acute phase and at 2 and 7 months of follow-up. Digital subtraction angiography identified the peripheral AVM when the patient experienced rehemorrhaging 1 year after his initial presentation. This case illustrates the need for a complete diagnostic evaluation including conventional angiography in cases of idiopathic ICH in children.

Arterial ischemic stroke: experience in Chinese children

The aim of this study was to review cases of pediatric arterial ischemic stroke among Chinese subjects and thereby evaluate risk factors, clinical and neuroimaging features, and treatment, to establish a reasonable guideline for assessment and management of the disease. Between 1996 and 2006, 157 children (male:female ratio, 1.4:1) with arterial ischemic stroke were identified at Beijing Children's Hospital. The median age at stroke was 32 months (range, 4-192). Among patients with determined etiology, infections (12.1%), moyamoya disease (12.1%), and trauma (10.8%) were the most common. In 51 patients, there were no obvious risk factors (32.5%). Hemiplegia was the most common presenting feature (81.5%). The region of left middle cerebral artery was most frequently affected (36.3%), followed by the right middle cerebral artery (29.9%). Of the 157 patients, 56 were treated by intravenous thrombolytic agents (35.7%), all but one of them successfully (the one exception involving hemorrhagic complication). Randomized controlled trials are needed to establish primary prevention, acute treatment, and secondary prevention of pediatric ischemic stroke.

[Arterial ischemic stroke in the healthy child. Practical approach (neonate and foetus excluded)]

Primary stroke can be due to embolism or an obstructive process of the vascular wall. Embolism may come from a parietal lesion of a large artery in the neck (traumatic dissections), from a cryptic cardiopathy, from a venous thrombosis associated with a right-left shunt. Among pathologies of endocranial arteries, the most frequent is the acute, postviral arteriopathy of the sus-clinoïd carotid, which evolves toward stabilisation or regression. Insidious obstructive arteriopathies of the Willis circle, including development of a transparenchymal suppletive circulation (Moya-Moya disease), cumulate chronic circulatory insufficiency and repetitive strokes. Inflammatory multifocal cerebral arteriopathies mainly involve mean and small arteries. Most of them are secondary to a multisystemic disease, but some are primary. The basic investigation is anatomical and begins with MRI. Emergency conventional cerebral angiography is discussed when heparinotherapy is difficult to decide (evolutive thrombosis), or when an endovascular intervention appears possible (anoeuvrism). Secondarily, conventional angiography is indicated in any chronic situation where a precise anatomical follow-up is necessary. Investigations of the cardiovascular system, of the thrombophilic risk, of a dysimmune process are discussed according to the clinico-anatomical diagnosis.

Cerebellar infarction in the territory of the superior cerebellar artery in children

Posterior circulation infarction is uncommon in children. Vertebral artery dissection is an unusual cause of posterior circulation infarction in children. We report on a 12-year-old boy with spontaneous left-extracranial vertebral artery dissection associated with isolated ipsilateral superior cerebellar artery territory infarction, diagnosed clinically and by brain computed tomography, magnetic resonance imaging, and magnetic resonance angiography. Cerebral angiography demonstrated a flame-like occlusion of the left vertebral artery at level C(2)-C(3), and indicated that artery-to-artery embolus may be a mechanism of superior cerebellar artery territory infarction. We emphasize that vertebral artery dissection should be considered in a child with acute signs of posterior circulation ischemia.