The Value of ¹⁸F-FDG PET/CT in Evaluating Cognitive Function in Children with Epilepsy

Objectives: Epilepsy is often accompanied by impairment of cognitive functions.To assess the relationship between glucose metabolism in brain and IQ in children with refractory epilepsy,we evaluated the regional glucose uptake and cognitive function.

Methods: Ninety (50 males and 40 females) 18F-FDG PET/CT brain studies of children with refractory epilepsy from March 2014 to August 2017 were retrospectively analyzed.All participants were administered the Wechsler Intelligence Scale for Children-Fourth Edition(WISC-IV).The core subtests and index scores were analyzed to detect cognitive problems.

Results: Later age at onset was correlated with higher WISC-IV core subtests and index scores(Similarities,Picture Concepts,Vocabulary,Matrix Reasoning,Perceptual reasoning index).Age was inversely correlated with Comprehension,Symbol Search and verbal comprehension index(VCI).Active duration was inversely correlated with Similarities,Vocabulary,Comprehension,VCI and full-scale IQ(FSIQ).Block Design and Comprehension for the females were both lower than males.Similarities,Vocabulary,VCI and FSIQ for children with positive magnetic resonance imaging(MRI) findings findings were lower than those with negative findings.The Vocabulary differed significantly between children with left-,right- and bilateral hemisphere abnormal hypometabolism.The Block Design,Digit Span,Picture Concepts,Matrix Reasoning,Perceptual reasoning index(PRI),working memory index(WMI),FSIQ of children with multifocal abnormal hypometabolism were lower than unifocal abnormal hypometabolism.The Similarities,Vocabulary,Comprehension,VCI of the children with unifocal abnormal hypometabolism in temporal lobe were lower than those in extratemporal lobe.Of the children with unifocal abnormal hypometabolism(27boys and 13girls),asymmetry index(AI) was not significantly related to age,age at onset,active duration,core subtests or index scores.

Conclusions: The metabolic abnormalities in brain were associated with the scores of WISC-IV.Along with WISC-IV,the 18F-FDG PET/CT can assess the cognitive function in children with epilepsy.|AI| may be of limited value on the evaluation of cognitive impairment in children with epilepsy. KEY WORDS: Epilepsy,positron emission tomography(PET),glucose metabolism,cognitive function