Simple Partial Status of Forced Thinking Originated in the Mesial Temporal Region: Intracranial Foramen Ovale Electrode Recording and Ictal PET

Forced thinking (FT) is a rare epileptic phenomenon which is usually seen in patients with frontal lobe epilepsy. We report a rare case of mesial temporal lobe epilepsy presenting FT as simple partial status epilepticus. A 50-year-old woman with left hippocampal sclerosis developed a prolonged episode of continuous FT for five days after she experienced a clustering of complex partial seizures during the period of preoperative video-electroencephalography (EEG) monitoring. The EEG demonstrated continuous focal ictal discharges in the left foramen ovale electrodes. Positron emission tomography showed focal glucose hypermetabolism in the left mesial temporal region. This case indicates that the anatomical substrate for the development of FT is located in the mesial temporal region as well as the frontal lobe, and prolonged FT can occur as a seizure manifestation.