Ketosis and Epilepsy: 31P Spectroscopic Imaging at 4.1 T

Abstract
Summary: Purpose: To determine whether changes in the high‐energy phosphates occur with use of the ketogenic diet in patients with intractable epilepsy. Methods: 31P magnetic resonance spectroscopic imaging studies were performed at 4.1 T in seven patients with intractable epilepsy (four Lennox‐Gastaut syndrome, one absence, one primary generalized tonic‐clonic, and one partial complex) before and after institution of the ketogenic diet. Coronal 1H anatomic imaging also was performed to provide correlation to the 31P data. Results: Taking the patients as a group, the ratio of phosphocreatine (PC)/γ‐adenosine triphosphate (ATP) measured at baseline (regular diet) compared with that measured after the ketogenic diet showed a small but significant increase from 0.61 ± 0.08 to 0.69 ± 0.08 (p < 0.05). Comparing the ratio of PCr inorganic phosphorus (Pi) measured at baseline with the postketogenic diet, there was a significant increase from 2.45 ± 0.27 to 2.99 ± 0.44 (p < 0.05). Conclusions: As a group, improvement of energy metabolism occurs with use of the ketogenic diet. This is in agreement with the chronic ketosis studies performed earlier in rodents.