YooSeok Kwon1, YoungSoon Yang2, Jae-Won Jang3, Young Ho Park1, JungEun Kim1, Seong-Ho Park1, SangYun Kim4. 1. Department of Neurology, Seoul National University Bundang Hospital & Seoul National University College of Medicine, Republic of Korea. 2. Department of Neurology, Veterans Hospital, Seoul Medical Center, Republic of Korea. 3. Department of Neurology, College of Medicine, Kangwon National University, Republic of Korea. 4. Department of Neurology, Seoul National University Bundang Hospital & Seoul National University College of Medicine, Republic of Korea. Electronic address: neuroksy@snu.ac.kr.
Abstract
PURPOSE: Transient global amnesia (TGA) is a syndrome of unknown etiology. Electroencephalographic (EEG) abnormalities in TGA have been reported previously. We analyzed the frequency and characteristics of EEG abnormalities in patients with TGA. METHODS: We collected EEGs of patients with a clinical diagnosis of TGA who had visited the emergency room or the outpatient clinic over a period of 8 years and compared clinical and demographic characteristics of the patients with normal EEGs with those with abnormal EEGs. RESULTS: EEG abnormalities were found in 35 (22.9%) out of 153 patients and epileptiform discharges were seen in 26 (74.3%) out of these 35 patients. Spikes or sharp waves were detected on the left side only (48.6%) or on both sides (25.7%), but none of the patients showed spikes or sharp waves on right side only. In six patients the EEG had normalized within three months of presentation, in ten within six months, and in twelve by one year. The EEG remained abnormal in eleven out of the 23 patients one year after presentation. CONCLUSION: In this largest consecutive EEG study at one center, the proportion of patients with TGA in whom epileptiform discharges were demonstrated within days of the episode of TGA was significantly higher than in the previous literature. EEG abnormalities such as spikes or sharp waves spontaneously disappeared in almost half of cases over one-year of follow-up. There was a clear left dominance of EEG abnormalities in patients with TGA.
PURPOSE: Transient global amnesia (TGA) is a syndrome of unknown etiology. Electroencephalographic (EEG) abnormalities in TGA have been reported previously. We analyzed the frequency and characteristics of EEG abnormalities in patients with TGA. METHODS: We collected EEGs of patients with a clinical diagnosis of TGA who had visited the emergency room or the outpatient clinic over a period of 8 years and compared clinical and demographic characteristics of the patients with normal EEGs with those with abnormal EEGs. RESULTS: EEG abnormalities were found in 35 (22.9%) out of 153 patients and epileptiform discharges were seen in 26 (74.3%) out of these 35 patients. Spikes or sharp waves were detected on the left side only (48.6%) or on both sides (25.7%), but none of the patients showed spikes or sharp waves on right side only. In six patients the EEG had normalized within three months of presentation, in ten within six months, and in twelve by one year. The EEG remained abnormal in eleven out of the 23 patients one year after presentation. CONCLUSION: In this largest consecutive EEG study at one center, the proportion of patients with TGA in whom epileptiform discharges were demonstrated within days of the episode of TGA was significantly higher than in the previous literature. EEG abnormalities such as spikes or sharp waves spontaneously disappeared in almost half of cases over one-year of follow-up. There was a clear left dominance of EEG abnormalities in patients with TGA.
Authors: Jae-Won Jang; Young Ho Park; So Young Park; Min Jeong Wang; Jae-Sung Lim; Sung-Hun Kim; In KooK Chun; Youngsoon Yang; SangYun Kim Journal: PLoS One Date: 2015-12-21 Impact factor: 3.240