Pediatric stroke: clinical findings and radiological approach

Pediatric Stroke from Bench to Bedside: A Single-Center Experience in Saudi Arabia

Purpose

Stroke is a leading cause of severe long-term disability and death worldwide. This study aimed to determine the genetic background, causative factors, and diagnostic and outcome measures of pediatric stroke in an area endemic to sickle cell disease (SCD).

Patients and Methods

This retrospective review analyzed pediatric patients with acute stroke who were admitted to King Fahd Hospital of the University, Eastern Province, Saudi Arabia, between January and June 2019. We assessed 49 cases based on computed tomography (CT) and magnetic resonance imaging (MRI) findings. Patients with incomplete records or unavailable radiological images were excluded.

Results

A high likelihood of familial coexistence of stroke was detected in patients with affected siblings (33%). Among various central nervous system manifestations, motor weakness (28.6%) and headache (20.4%) were the most common symptoms/signs. Hypoxic-ischemic encephalopathy (HIE) (28.6%), SCD (22.5%), and moyamoya disease (14.3%) were the most prevalent underlying etiologies. CT without intravenous contrast was the most used initial imaging technique (92.5%). An arterial blockage was more prevalent (53.4%) than a venous infarct (46.6%) (p = 0.041), while arterial ischemic stroke was more prevalent (56.5%) than hemorrhagic stroke (43.5%). The middle cerebral artery (MCA) was most affected (63.5%), followed by the anterior cerebral artery (22.7%) and posterior cerebral artery (13.6%). Most patients were managed with medical treatment (86.1%). No mortalities occurred during the initial hospital stay. The mean length of hospital stay was 12 days.

Conclusion

HIE was the most prevalent etiology of pediatric stroke. Motor weakness and headache were the most common initial manifestations. Arterial ischemic stroke was more prevalent than venous or hemorrhagic stroke. Considering the rarity of pediatric stroke, future studies should be performed with a aborative effort nationally and internationally.

Paediatric brainstem: A comprehensive review of pathologies on MR imaging

The brainstem is a midline structure formed by the midbrain, pons and medulla and is a home for various vital neurological centres of the human body. A diverse spectrum of disease entities can involve the brainstem, which includes infections, metabolic disorders, demyelination, vascular conditions, neurodegenerative disorders and tumours. Brainstem involvement can be primary or secondary, i.e., as part of systemic disorders. Due to the overlapping clinical presentation and symptomatology, imaging plays a decisive role in the detection, localisation and characterisation of brainstem pathologies. Magnetic resonance imaging (MRI) is the modality of choice and the use of advanced MR techniques such as diffusion-weighted imaging and spectroscopy can be especially helpful in providing a tenable diagnoses. This article is a compilation of the MR imaging manifestations of a spectrum of common and uncommon brainstem pathologies that can be encountered in the paediatric age group.

Teaching Points

• The paediatric brainstem can be afflicted by many pathologies that may overlap clinico-radiologically.

• MRI is the best modality for the localisation and diagnosis of brainstem pathologies.

• Diffusion-weighted imaging is useful in the diagnosis of vascular and metabolic disorders.

• Occasionally, demyelination and neoplasms can be indistinguishable on imaging.

Role of Diffusion-weighted Imaging in Acute Stroke Management using Low-field Magnetic Resonance Imaging in Resource-limited Settings

A variety of imaging modalities exist for the diagnosis of stroke. Several studies have been carried out to ascertain their contribution to the management of acute stroke and to compare the benefits and limitations of each modality. Diffusion-weighted imaging (DWI) has been described as the optimal imaging technique for diagnosing acute ischemic stroke, yet limited evidence is available on the value of DWI in the management of ischemic stroke with low-field magnetic resonance (MR) systems. Although high-field MR imaging (MRI) is desirable for DWI, low-field scanners provide an acceptable clinical compromise which is of importance to developing countries posed with the challenge of limited availability of high-field units. The purpose of this paper was to systematically review the literature on the usefulness of DWI in acute stroke management with low-field MRI scanners and present the experience in Nigeria.

A case of postvaricella cerebral angiopathy with a good outcome in a child

Cerebral vasculopathy is a serious but uncommon complication of varicella-zoster-virus (VZV) infection. Diagnosis is based on a recent history of VZV infection, signs and symptoms of transient ischemic attack or stroke, and vascular anomalies on neuroimaging. We report a case of postvaricella cerebral angiopathy in a 5-year-old child, who was admitted after three episodes of transient right hemiplegia, each one lasting a few minutes. He had contracted chicken pox, the month prior to admission. Brain magnetic resonance imaging showed hyperintense signals in the left lenticular and caudate nuclei, which can be considered to be a result of vasculopathy.

Inherited prothrombotic risk factors in children with first ischemic stroke

Stroke in children is a heterogeneous disorder. Over 100 risk factors for stroke have been reported and genetic predisposition to stroke has been established. The most frequently reported risk factors are congenital heart malformations, hemolytic anemias, collagen vascular diseases, some rare inborn metabolic disorders, trauma, infection and thrombophilia. The aim of this article is to provide an overview of investigated inherited prothrombotic risk factors in children with first ischemic stroke. Various prothrombotic risk factors have been investigated in pediatric stroke including elevated homocysteine and lipoprotein (a), antithrombin, protein C and protein S deficiency, Factor V Leiden, Factor II G20210A and plasminogen activator inhibitor-1 4G/5G polymorphism. Despite similar criteria for inclusion of different studies in meta-analyses investigating first ischemic stroke in children, the obtained results were not consistent for all prothrombotic risk factors. The discrepancies found could be explained by methodological issues like different sample sizes, patient populations included and lack of controls. In order to provide the necessary power for randomized control trials, multi-center, multi-national approaches like International Pediatric Stroke Study have been initiated with the aim to describe risk factors for childhood stroke and explore their relationship with presentation, age, geography, and infarct characteristics. Although it is evident from numerous studies that the frequency of inherited prothrombotic factors is increased in pediatric stroke, single thrombophilia does not fully explain stroke in a child as it represents only a mild risk factor. Further studies are needed, as improved understanding of underlying mechanisms will improve primary and secondary prevention of childhood stroke.