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PT  - JOURNAL ARTICLE
AU  - Wright, J.N.
AU  - Saneto, R.P.
AU  - Friedman, S.D.
TI  - β-Hydroxybutyrate Detection with Proton MR Spectroscopy in Children with Drug-Resistant Epilepsy on the Ketogenic Diet
AID  - 10.3174/ajnr.A5648
DP  - 2018 Jul 01
TA  - American Journal of Neuroradiology
PG  - 1336--1340
VI  - 39
IP  - 7
4099  - http://www.ajnr.org/content/39/7/1336.short
4100  - http://www.ajnr.org/content/39/7/1336.full
SO  - Am. J. Neuroradiol.2018 Jul 01; 39
AB  - BACKGROUND AND PURPOSE: The ketogenic diet, including both classic and modified forms, is an alternative to antiepileptic medications used in the treatment of drug-resistant epilepsy. We sought to evaluate the utility of proton MR spectroscopy for the detection of β-hydroxybutyrate in a cohort of children with epilepsy treated with the ketogenic diet and to correlate brain parenchymal metabolite ratios obtained from spectroscopy with β-hydroxybutyrate serum concentrations.MATERIALS AND METHODS: Twenty-three spectroscopic datasets acquired at a TE of 288 ms in children on the ketogenic diet were analyzed with LCModel using a modified basis set that included a simulated β-hydroxybutyrate resonance. Brain parenchymal metabolite ratios were calculated. Metabolite ratios were compared with serum β-hydroxybutyrate concentrations, and partial correlation coefficients were calculated using patient age as a covariate.RESULTS: β-hydroxybutyrate blood levels were highly correlated to brain β-hydroxybutyrate levels, referenced as either choline, creatine, or N-acetylaspartate. They were inversely but more weakly associated with N-acetylaspartate, regardless of the ratio denominator. No strong concordance with lactate was demonstrated.CONCLUSIONS: Clinical MR spectroscopy in pediatric patients on the ketogenic diet demonstrated measurable β-hydroxybutyrate, with a strong correlation to β-hydroxybutyrate blood levels. These findings may serve as an effective tool for noninvasive monitoring of ketosis in this population. An inverse correlation between serum β-hydroxybutyrate levels and brain tissue N-acetylaspartate suggests that altered amino acid handling contributes to the antiepileptogenic effect of the ketogenic diet.BHBβ-hydroxybutyrateGABAgamma-aminobutyric acidKDketogenic dietMADmodified Atkins diet