Alireza Fallahi1, Mohammad Pooyan2, Jafar Mehvari Habibabadi3, Mohammad-Reza Nazem-Zadeh4,5. 1. Biomedical Engineering Department, Engineering Faculty, Shahed University, Tehran, Iran. 2. Biomedical Engineering Department, Engineering Faculty, Shahed University, Tehran, Iran. pooyan@shahed.ac.ir. 3. Isfahan Neuroscience Research Center, Isfahan University of Medical Sciences, Isfahan, Iran. 4. Research Center for Molecular and Cellular Imaging, Advanced Medical Technologies and Instruments Institute (AMTII), Tehran University of Medical Sciences, Tehran, Iran. mnazemzadeh@tums.ac.ir. 5. Physics and Biomedical Engineering Department, Tehran University of Medical Sciences, Tehran, Iran. mnazemzadeh@tums.ac.ir.
Abstract
OBJECTIVE: To develop a decision-making tool to evaluate and compare the performance of neuroimaging markers with clinical findings and the significance of attributes for presurgical lateralization of mesial temporal lobe epilepsy (mTLE). METHODS: Thirty-five unilateral mTLE patients who qualified as candidates for surgical resection were studied. Seizure semiology, ictal EEG, ictal epileptogenic zone, interictal-irritative zone, and MRI findings were used as clinical markers. Hippocampal T1 volumetry and FLAIR intensity, DTI estimated; mean diffusivity (MD) in the hippocampus and fractional anisotropy (FA) in posteroinferior cingulum and crus of fornix, and the output of logistic regression method on volumetrics of the hippocampus, amygdala, and thalamus were adopted as neuroimaging markers. The self-organizing map (SOM) method was applied to markers to provide predictive methods for mTLE lateralization. RESULTS: The SOM clustered all clinical attributes correctly with 100% accuracy and sensitivity for both the left and right mTLE. Among the clinical markers, seizure semiology and interictal-irrelative zone are the most sensitive attribute for the left-mTLE group lateralization. The accuracy achieved by applying the SOM method to the neuroimaging attributes was 94%, while the sensitivity was achieved 90% for left and 100% for right mTLE. SOM evidence indicated that the hippocampal volume is the most sensitive attribute for the prediction of the laterality in left-mTLE groups. CONCLUSION: The proposed SOM method showed that neuroimaging markers may not replace with clinical findings. Nevertheless, multimodal neuroimaging can play an effective role in preoperative lateralization to reduce the costs and risks of surgical resection.
OBJECTIVE: To develop a decision-making tool to evaluate and compare the performance of neuroimaging markers with clinical findings and the significance of attributes for presurgical lateralization of mesial temporal lobe epilepsy (mTLE). METHODS: Thirty-five unilateral mTLE patients who qualified as candidates for surgical resection were studied. Seizure semiology, ictal EEG, ictal epileptogenic zone, interictal-irritative zone, and MRI findings were used as clinical markers. Hippocampal T1 volumetry and FLAIR intensity, DTI estimated; mean diffusivity (MD) in the hippocampus and fractional anisotropy (FA) in posteroinferior cingulum and crus of fornix, and the output of logistic regression method on volumetrics of the hippocampus, amygdala, and thalamus were adopted as neuroimaging markers. The self-organizing map (SOM) method was applied to markers to provide predictive methods for mTLE lateralization. RESULTS: The SOM clustered all clinical attributes correctly with 100% accuracy and sensitivity for both the left and right mTLE. Among the clinical markers, seizure semiology and interictal-irrelative zone are the most sensitive attribute for the left-mTLE group lateralization. The accuracy achieved by applying the SOM method to the neuroimaging attributes was 94%, while the sensitivity was achieved 90% for left and 100% for right mTLE. SOM evidence indicated that the hippocampal volume is the most sensitive attribute for the prediction of the laterality in left-mTLE groups. CONCLUSION: The proposed SOM method showed that neuroimaging markers may not replace with clinical findings. Nevertheless, multimodal neuroimaging can play an effective role in preoperative lateralization to reduce the costs and risks of surgical resection.
Authors: Luc Rubinger; Carol Chan; Felice D'Arco; Rahim Moineddin; Osama Muthaffar; James T Rutka; O Carter Snead; Mary Lou Smith; Elysa Widjaja Journal: Epilepsia Date: 2015-12-30 Impact factor: 5.864
Authors: Maria Luisa Lopez-Acevedo; Manuel Martinez-Lopez; Rafael Favila; Ernesto Roldan-Valadez Journal: Swiss Med Wkly Date: 2012-06-06 Impact factor: 2.193