Abstract

FMZ-PET to assess the efficacy and the mechanism of ketogenic diet in patients with intractable epilepsy

Author(s): Ryuichi Nishii*, Toshinori Hirai, Tatsuya Fujii, Tomohiro Kumada, Tatsuya Higashi, Shinya Kagawa, Yoshihiko Kishibe, Masaaki Takahashi, Hiroshi Yamauchi, Chio Okuyama & Shigeki Nagamachi

Objectives :-  A ketogenic diet (KD) is a strict dietary protocol that incorporates high-fat, low-protein, and low-carbohydrate foods. Increasing the levels of ketones became an eventual and effective treatment strategy for medically refractory epilepsy. Although several theories on the rationale for the anticonvulsant efficacy of KD have been hypothesized, the most important anticonvulsant mechanism of KD is still unknown. This study is the first report that evaluated the mechanism underlying the effect of KD in patients with intractable infantile epilepsy using FMZ-PET imaging studies.

Methods :-Six patients with intractable epilepsy (two females/four males; seizure-onset age: 0–30 months) were enrolled in this study. Medication-refractory seizures continued in all patients despite treatment with the anti-epilepsy drugs (AEDs), followed by two types of KD therapy; the classical KD menu or the MAD regimen. All patients underwent FMZ-PET before KD and at 1-5 months after induction of KD. Dynamic FMZ-PET scanning was acquired, followed by assessment of the BP images using the graphic plot method of Logan.

Results:- In KD-effective patients, the BPs of FMZ before KD were 1.31, 1.60 and 1.50, and those after induction of KD were 1.89, 2.13 and 2.07, respectively. In KD-partially effective patients, the BPs of FMZ before KD were 1.95 and 2.47, and those after induction of KD were 2.10 and 2.71, respectively. Conversely, in KD-ineffective case, the BP of FMZ was decreased from 3.91 before KD to 3.58. The BP-change ratios were 1.44, 1.33 and 1.38 in the KD-effective patients, 1.08 and 1.10 in the KD-partially effective patients, and 0.92 in the KD-ineffective one.

Conclusion;- The results of current study suggested that KD may control seizures by increasing BP of BZR and that FMZ-PET imaging would be useful to assess the efficacy of KD therapy in patients with intractable epilepsy. Using MRI to pre-operatively evaluate breast blood supply is feasible without adding extra MRI time or contrast. 71% had dominant supply to the NAC, so every effort should be made to preserve it. The LOQ appears to be an optimal site for skin incisions. There is an asymmetry between cancer and HRS breasts mainly at the NAC’s level with neovascularization of that area.Patients with a single vessel supplying the NAC are at improved risk for necrosis.