Concordance of diffusion tensor imaging alterations with EEG lateralization in MR negative refractory temporal lobe epilepsy
Concordance of diffusion tensor imaging alterations with EEG lateralization in MR negative refractory temporal lobe epilepsy
Aim: In this study, we aimed to investigate the occult microstructural changes in both temporal lobes and their localizationconcordance with electroencephalogram (EEG) lateralization side in MR negative refractory temporal lobe epilepsies using diffusiontensor imaging (DTI).Material and Methods: Clinical files of 200 adult patients diagnosed with temporal lobe epilepsy and followed by neurologydepartment were reviewed. A total of 32 patients who had uncontrolled seizures despite antiepileptic medication and had normalMR findings were included in the study. Using DTI data, symmetric region of interests (ROIs) were replaced on each temporal whitematter to calculate parameters including fractional anisotropy (FA), radial diffusivity (RD) and axial diffusivity (AD). Mean values ofeach of these parameters were compared between the epileptogenic lateralization side on (EEG) and opposite temporal lobe.Results: FA and RD values were significantly different on lateralization side compared to normal side, whereas AD value showed nosignificant difference between two sides.Conclusion: The subtle microstructural abnormalities which cannot be discerned on routine conventional MRI practice in brainsof refractory TLE patients can be revealed by DTI. The localization of these DTI abnormalities mostly shows concordance withthe lateralization side on EEG. Awareness of the existence and degree of these alterations may be useful in determining medicaltreatment strategies or may be a guide in planning blind antiepileptic surgery.
___
- 1. Jacobs MP, Fischbach GD, Davis MR, et al. Future directions for epilepsy research. Neurology 2001;57; 1536-42.
- 2. Cendes F. Mesial temporal lobe epilepsy syndrome: an updated overview. J Neurol Neurosurg Psychiatry 2005;11:141-4.
- 3. Wehner T, Luders H. Role of neuroimaging in the presurgical evaluation of epilepsy. J Clin Neurol 2008; 4:1-16.
- 4. Tellez-Zenteno JF, Hernandez Ronquillo L, MoienAfshari F, et al. Surgical outcomes in lesional and non-lesional epilepsy: a systematic review and metaanalysis. Epilepsy Res 2010; 89:310-8.
- 5. Yu Y, Chu L, Liu C, et al. Alterations of white matter network in patients with left and right non-lesional temporal lobe epilepsy. Eur Radiol 2019;29:6750-61.
- 6. Gross DW. Diffusion tensor imaging in temporal lobe epilepsy. Epilepsia 2011;52:32-4.
- 7. Mori S, Zhang J. Principles of diffusion tensor imaging and its applications to basic neuroscience research. Neuron 2006;51:527-39.
- 8. Kurtcan S, Alkan A, Yetis H, et al. Diffusion tensor imaging findings of the brainstem in subjects with tonsillar ectopia. Acta Neurol Belg 2018;118:39-45.
- 9. Le Bihan D, Mangin JF, Poupon C, et al. Diffusion tensor imaging: concepts and applications. J Magn Reson Imaging 2001;13:534-46.
- 10. Winklewski PJ, Sabisz A, Naumczyk P, et al. Understanding the Physiopathology Behind Axial and Radial Diffusivity Changes-What Do We Know? Front Neurol 2018;9:92.
- 11. Arfanakis K, Hermann BP, Rogers BP, et al. Seidenberg and M.E. Meyerand, Diffusion tensor MRI in temporal lobe epilepsy. Magn Reson Imaging 2002;20:511-9.
- 12. Gross DW, Concha L, Beaulieu C. Extratemporal white matter abnormalities in mesial temporal lobe epilepsy demonstrated with diffusion tensor imaging. Epilepsia 2006;47:1360-3.
- 13. Cascino GD, Jack CR, Parisi JE, et al. Magnetic resonance imaging-based volume studies in temporal lobe epilepsy: pathological correlations. Ann Neurol 1991;30:31-6.
- 14. Muhlhofer W, Tan YL, Mueller SG, et al. MRI-negative temporal lobe epilepsy-What do we know? Epilepsia 2017;58:727-42.
- 15. Noachtar S, Remi J. The role of EEG in epilepsy: a critical review. Epilepsy Behav 2009;15: 22-33.
- 16. Chen LS, Mitchell WG, Horton EJ, et al. Clinical utility of video-EEG monitoring. Pediatr Neurol 1995;12:220-4.
- 17. von Oertzen TJ. PET and ictal SPECT can be helpful for localizing epileptic foci. Curr Opin Neurol 2018;31: 184-91.
- 18. Liacu D, de Marco G, Ducreux D, et al. Diffusion tensor changes in epileptogenic hippocampus of TLE patients. Neurophysiol Clin 2010;40:151-7.
- 19. Widjaja E, Geibprasert S, Otsubo H, et al. Diffusion tensor imaging assessment of the epileptogenic zone in children with localization-related epilepsy. AJNR Am J Neuroradiol 2011;32:1789-94.
- 20. Lyra KP, Chaim KT, Leite CC, et al. Corpus callosum diffusion abnormalities in refractory epilepsy associated with hippocampal sclerosis. Epilepsy Res 2017;137:112-8.
- 21. Kim CH, Koo BB, Chung CK, et al. Thalamic changes in temporal lobe epilepsy with and without hippocampal sclerosis: a diffusion tensor imaging study. Epilepsy Res 2010;90:21-7.