Rinsho Shinkeigaku (Clinical Neurology)

Case Report

Ictal EEG pattern of transient epileptic amnesia in acute phase of non-herpetic limbic encephalitis

Tomoya Chiba, M.D.1)2), Namiko Henmi, M.D.1)3), Shuichiro Neshige, M.D., Ph.D.3)4), Kazushiro Takada, M.D., Ph.D.1), Akio Ikeda, M.D., Ph.D.5), Ryosuke Takahashi, M.D., Ph.D.3) and Masaru Yokoe, M.D., Ph.D.1)

1) Department of Neurology, Japan Community Health care Organization, Hoshigaoka Medical Centre
2) Department of Neurology, Osaka University Graduate School of Medicine
3) Department of Neurology, Kyoto University Graduate School of Medicine
4) Department of Clinical Neuroscience and Therapeutics, Hiroshima University Graduate School of Biochemical and Health Sciences
5) Department of Epilepsy, Movement Disorders and Physiology, Kyoto University Graduate School of Medicine

A 60-year-old, right-handed woman was admitted to our hospital for amnesia as the only neurological abnormal findings following the autonomic symptoms and transient episodes of loss of awareness. EEG during the amnesia showed rhythmic alpha activity arising from the left mid-temporal region. Although this ictal activity showed evolution in the frequency and amplitude, the location was limited in the bilateral temporal areas. After the EEG evaluation, her amnesia was resolved immediately, suggesting that her presentation was transient epileptic amnesia (TEA). Meanwhile, given the clinical course and MRI findings (high intensity in the bilateral mesial temporal areas, more on the left), she was diagnosed with non-herpetic limbic encephalitis and treated with steroid and anti-epileptic drugs, leading to the positive outcome. The ictal EEG findings during TEA as the one of the presentation in acute phase of non-herpetic limbic encephalitis may contribute to further investigation of underlying mechanism of TEA.
Full Text of this Article in Japanese PDF (4824K)

(CLINICA NEUROL, 60: 446−451, 2020)
key words: autoimmune epilepsy, temporal lobe epilepsy, epileptic discharges, EEG seizure pattern, complex partial seizure

(Received: 15-Jan-20)