Hemimegalencephaly: Evaluation with positron emission tomography

doi:10.1016/0887-8994(93)90005-W

Pediatric Neurology

Volume 9, Issue 1, January–February 1993, Pages 21-28

https://doi.org/10.1016/0887-8994(93)90005-W Get rights and content

Abstract

We performed positron emission tomographic (PET) studies with 2-deoxy-2[¹⁸F]fluoro-d-glucose in 8 children with hemimegalencephaly (HME). HME is a developmental brain malformation associated with epilepsy, hemianopsia, and varying degrees of developmental delay. We hypothesized that the relatively poor overall developmental outcome of surgically hemispherectomized HME patients as a group, compared to children undergoing hemispherectomy for Sturge-Weber syndrome or chronic focal encephalitis, is related to dysfunction of the structurally “normal” non-HME side and that PET would be helpful in the presurgical evaluation of HME patients with intractable epilepsy. Visual analysis of the non-HME side on PET clearly revealed evidence of cortical hypometabolism in 4 patients compared to controls. Seven children underwent epilepsy surgery. One child had a glucose metabolic pattern suggesting a cortical lamination defect in the non-HME hemisphere, bilateral independent seizure onset, and was not considered to be a surgical candidate. We found a general correlation between the pattern of glucose utilization in the less affected hemisphere and prognosis. Although the follow-up periods are short, it is recommended that HME children with intractable epilepsy undergo hemispherectomy in the first year of life in order to allow maximal brain plasticity to occur; however, preoperative evaluation should also include an assessment of the integrity of the non-HME hemisphere.

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Original articleHemimegalencephaly: Evaluation with positron emission tomography

Abstract

Pediatr Neurol

J Pediatr

Pediatr Neurol

Pediatr Neurol

Epilepsy Res

Epilepsy Res

A case of unilateral megalencephaly

Dev Med Child Neurol

Unilateral megalencephaly with nerve cell hypertrophy. An anatomical and quantitative histochemical study

Brain Res

Unilateral megalencephaly: Hamartoma or neoplasm?

Neurology

Unilateral megalencephaly, cerebral cortical dysplasia, neuronal hypertrophy, and heterotopia: Cytomorphometric, fluorometric cytochemical, and biochemical analyses

Acta Neuropathol

Hemimegalencephaly: A clinicopathological study of four cases

Neuropathol Appl Neurobiol

Megalencephaly

Hemimegalencephaly: Diagnosis and treatment

Electroencephalographic aspects of hemimegalencephaly

Dev Med Child Neurol

Hemimegalencephaly and intractable epilepsy: Benefits of hemispherectomy

Epilepsia

Rasmussen's syndrome: Symptomatology of the syndrome of chronic encephalitis and seizures

Hemispherectomy for Sturge-Weber syndrome

Childs Brain

Anatomical localization schemes for use in positron computed tomography using a specially designed head holder

J Comput Assist Tomogr

Maturational changes in cerebral function in infants determined by 18FDG positron emission tomography

Science

Original article
Hemimegalencephaly: Evaluation with positron emission tomography