Aim This study aimed to evaluate the efficacy and retention rate of a ketogenic diet (KD) and assess factors that influence the efficacy of KD therapy in children with refractory epilepsy (RE).

Methods We retrospectively studied the efficacy and retention rate of 56 RE children who accepted KD therapy from January 2013 to December 2019. Patients who had a ≥50% reduction in seizure frequency were defined as responders. The retention rate was calculated as the proportion of children who continued KD/the total number of children who were followed up at the time of enrollment. We also analyzed the effects of different factors (such as gender, KD initial age, KD duration, the type of epilepsy syndrome, and others) on the efficacy of the KD.

Results (1) The efficacy rates for the KD at 3, 6, 12, and 18 months were 51.8, 53.6, 39.2, and 23.2%, respectively. (2) The retention rates for the KD at 3, 6, 12 and 18 months were 100, 69.6, 41.1, and 23.2%, respectively. (3) There was no correlation between efficacy and gender, epilepsy onset age, the type of epilepsy syndrome, electroencephalogram improvement, or the number of antiseizure medications, while cranial magnetic resonance imaging (MRI) abnormalities, KD duration, and KD initial age affected its efficacy at 3 months.

Conclusion (1) KD therapy for refractory childhood epilepsy was effective and produced a high retention rate. (2) MRI abnormalities and the initial age and duration of KD influenced its short-term efficacy in RE children.

目的 本研究旨在评估生酮饮食（KD）的疗效和保留率，并评估影响生酮饮食治疗儿童难治性癫痫（RE）疗效的因素。

方法 回顾性研究2013年1月至2019年12月接受KD治疗的56例RE患儿的疗效及维持率，癫痫发作频率降低≥50%的患者定义为有效者。保留率计算为继续进行 KD 的儿童比例 / 入组时接受随访的儿童总数。我们还分析了不同因素（如性别、KD 初始年龄、KD 持续时间、癫痫综合征类型等）对 KD 疗效的影响。

结果 （1）生酮饮食3、6、12、18个月有效率分别为51.8、53.6、39.2、23.2%。(2) KD在3、6、12和18个月的保留率分别为100、69.6、41.1和23.2%。(3)疗效与性别、癫痫发作年龄、癫痫综合征类型、脑电图改善、抗癫痫药物使用次数无相关性，而头颅磁共振成像(MRI)异常、KD持续时间、KD起始年龄影响它的疗效在 3 个月。

结论 （1）KD治疗难治性儿童癫痫疗效显着，保留率高。(2)MRI异常、KD的起始年龄和持续时间影响其在RE患儿中的近期疗效。