Identifying the affected hemisphere with a multimodal approach in MRI-positive or negative, unilateral or bilateral temporal lobe epilepsy.
Patients with non-lesional or bilateral temporal-lobe epilepsy (TLE) are often excluded from surgical treatment. This study investigated focus lateralization in TLE to understand identification of the affected hemisphere with regard to non-lesional or bilateral affection and postsurgical outcome. A total of 24 TLE patients underwent presurgical evaluation with magnetic resonance imaging (MRI), proton magnetic resonance spectroscopy ((1)H-MRS), video-electroencephalogram (video-EEG), and/or intracranial EEG (icEEG), and they were classified as MRI-positive or negative, unilateral or bilateral TLE cases. In patients with positive-MRI, MRI and (1)H-MRS indicated high (100%) concordant lateralization to EEG findings in unilateral TLE, and moderate (75%) concordance to icEEG findings in bilateral TLE; whereas in patients with negative-MRI, (1)H-MRS indicated moderate (60%-75%) concordance to EEG and/or icEEG in unilateral TLE, and relatively low (50%) concordance to icEEG in bilateral TLE. Ninety point nine percent of patients with unilateral TLE and 41.7% of patients with bilateral TLE (including 50% of MRI-negative bilateral TLE) became seizure-free. The MRS findings were not correlated with seizure outcome, while non-seizure-free patients had an insignificantly higher percentage of contralateral N-acetyl aspartate (NAA) reduction compared with seizure-free patients, indicating the relatively low predictive value of (1)H-MRS for surgical outcome. Further, EEG and icEEG findings were significantly correlated with seizure outcome, and for patients with positive MRI, MRI findings were also correlated with seizure outcome, indicating the predictive value of these modalities. The results suggested that a multimodal approach including neuroimaging, EEG, and/or icEEG could identify seizure focus in most cases, and provide surgical options for non-lesional or bilateral TLE patients with a possible good outcome.
School of Biomedical Engineering, Capital Medical University, Beijing, People's Republic of China.
Jing
J
Zhang
Department of Functional Neurolog and Neurosurgery, Beijing Haidian Hospital, Beijing, People's Republic of China.
Qingzhu
Q
Liu
Department of Functional Neurolog and Neurosurgery, Beijing Haidian Hospital, Beijing, People's Republic of China.
Shanshan
S
Mei
Department of Functional Neurolog and Neurosurgery, Beijing Haidian Hospital, Beijing, People's Republic of China.
Xiaoming
X
Zhang
School of Biomedical Engineering, Capital Medical University, Beijing, People's Republic of China.
Weifang
W
Liu
School of Biomedical Engineering, Capital Medical University, Beijing, People's Republic of China.
Hui
H
Chen
School of Biomedical Engineering, Capital Medical University, Beijing, People's Republic of China.
Hong
H
Xia
School of Biomedical Engineering, Capital Medical University, Beijing, People's Republic of China.
Zhen
Z
Zhou
Department of Functional Neurolog and Neurosurgery, Beijing Haidian Hospital, Beijing, People's Republic of China.
Xiaofei
X
Wang
Department of Functional Neurolog and Neurosurgery, Beijing Haidian Hospital, Beijing, People's Republic of China.
Yunlin
Y
Li
MRS; focus lateralization; neuroimaging; surgical outcome