Functional MRI in epilepsy – Comparison of Lateralization index and language scoring

Anuj Prabhakar; Niranjan Khandelwal; Sameer Vyas; Vivek Gupta; Parampreet S Kharbanda; Manju Mohanty

doi:10.4103/ijri.IJRI_281_18

Indian Journal of Radiology and Imaging, Inhaltsverzeichnis

CC BY-NC-ND 4.0 · Indian J Radiol Imaging 2019; 29(02): 168-179
DOI: 10.4103/ijri.IJRI_281_18

Neuroradiology

Functional MRI in epilepsy – Comparison of Lateralization index and language scoring

Authors

Anuj Prabhakar

Department of Neuro Imaging and Interventional Neuroradiology, AIIMS, New Delhi
Niranjan Khandelwal

Departments of Radiodiagnosis, Post Graduate Institute of Medical Imaging and Research, Chandigarh, India
Sameer Vyas

Departments of Radiodiagnosis, Post Graduate Institute of Medical Imaging and Research, Chandigarh, India
Vivek Gupta

Departments of Radiodiagnosis, Post Graduate Institute of Medical Imaging and Research, Chandigarh, India
Parampreet S Kharbanda

Neurology, Post Graduate Institute of Medical Imaging and Research, Chandigarh, India
Manju Mohanty

Neurosurgery, Post Graduate Institute of Medical Imaging and Research, Chandigarh, India

Verantwortlicher Herausgeber dieser Rubrik:

Abstract

Aims: To evaluate the role of functional magnetic resonance imaging (fMRI) in epilepsy management and to ascertain whether laterality index (LI) derived from fMRI data, using routinely utilized paradigms, can serve as an adjunct to/or replace preoperative neuropsychological testing for evaluation of language lateralization and impairment. Materials and Methods: This was a prospective study which included 20 consecutive patients with a clinical diagnosis of temporal lobe epilepsy over a period of 1 year. Neuropsychological assessment included oral word association test and animal names test. The scores of both tests were compared with normographic data provided in the NIMHANS neuropsychology battery. Three fMRI paradigms were used, namely, picture naming, word generation, and sentence completion. Processing and statistical analysis were performed subsequently. Results and Conclusion: Right temporal lobe epilepsy (RTLE) was seen in 12 patients and left temporal lobe epilepsy (LTLE) in 8 patients. All patients were right handed. The activation pattern was predominantly left lateralized. Language lateralization varied with the type of paradigm. The overall percentage of patients showing left lateralization ranged from 44.00% for the picture naming task to 75% for the sentence completion. Reduced left lateralization was noted in both LTLE and RTLE patients. A negative correlation was observed in LTLE patients between performance in the verbal fluency and the lateralization index in the temporal and parietal regions of interest (ROI) in the word generation paradigm, suggesting that increased left lateralization was associated with a poorer score on neuropsychological tests. In RTLE patients, however, there was no significant correlation between performance in neuropsychological tests and LI. In conclusion, language lateralization using LI can serve as an adjunct during preoperative evaluation. However, it cannot replace neuropsychological testing.

Keywords

Epilepsy - functional magnetic resonance imaging - language - lateralization

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Referenzen

References
1 Leonardi M, Ustun TB. The global burden of epilepsy. Epilepsia 2002; 43: 21-5
2 Tripathi M, Jain DC, Devi MG, Jain S, Saxena V, Chandra PS. et al. Need for a national epilepsy control program. Ann Indian Acad Neurol 2012; 15: 89-93
3 Gourie-Devi M, Gururaj G, Satishchandra P, Subbakrishna DK. Prevalence of neurological disorders in Bangalore, India: A community-based study with a comparison between urban and rural areas. Neuroepidemiology 2004; 23: 261-8
4 Meyer A-C, Dua T, Ma J, Saxena S, Birbeck G. Global disparities in the epilepsy treatment gap: A systematic review. Bull World Health Organ 2010; 88: 260-6
5 French JA. Refractory epilepsy: A clinical overview. Epilepsia 2007; 48 Suppl (01) 3-7
6 Perry MS, Duchowny M. Surgical versus medical treatment for refractory epilepsy: Outcomes beyond seizure control. Epilepsia 2013; 54: 2060-70
7 Thom M. Review: Hippocampal sclerosis in epilepsy: A neuropathology review. Neuropathol Appl Neurobiol 2014; 40: 520-43
8 Rosazza C, Ghielmetti F, Minati L, Vitali P, Giovagnoli AR, Deleo F. et al. Preoperative language lateralization in temporal lobe epilepsy (TLE) predicts peri-ictal, pre- and post-operative language performance: An fMRI study. NeuroImage Clin 2013; 3: 73-83
9 Woermann FG, Jokeit H, Luerding R, Freitag H, Schulz R, Guertler S. et al. Language lateralization by Wada test and fMRI in 100 patients with epilepsy. Neurology 2003; 61: 699-701
10 Oldfield RC. The assessment and analysis of handedness: The Edinburgh inventory. Neuropsychologia 1971; 9: 97-113
11 Rao SL, Subbakrishna DK, Gopukumar K. NIMHANS neuropsychology battery-2004, manual. 1st ed. Bangalore: Natl. Inst. Ment. Health Neurosci; 2004: 267
12 Wilke M, Lidzba K. LI-tool: A new toolbox to assess lateralization in functional MR-data. J Neurosci Methods 2007; 163: 128-36
13 Wilke M, Schmithorst VJ. A combined bootstrap/histogram analysis approach for computing a lateralization index from neuroimaging data. NeuroImage 2006; 33: 522-30
14 Arora J, Pugh K, Westerveld M, Spencer S, Spencer DD, Todd Constable R. Language lateralization in epilepsy patients: fMRI validated with the Wada procedure. Epilepsia 2009; 50: 2225-41
15 Gupta S. fMRI for mapping language networks in neurosurgical cases. Indian J Radiol Imaging 2014; 24: 37
16 Pujol J, Deus J, Losilla JM, Capdevila A. Cerebral lateralization of language in normal left-handed people studied by functional MRI. Neurology 1999; 52: 1038-43
17 Knecht S, Deppe M, Dräger B, Bobe L, Lohmann H, Ringelstein EB. et al. Language lateralization in healthy right-handers. Brain 2000; 123: 74-81
18 Thivard L, Hombrouck J, Tézenas du Montcel S, Delmaire C, Cohen L, Samson S. et al. Productive and perceptive language reorganization in temporal lobe epilepsy. NeuroImage 2005; 24: 841-51
19 Janszky J, Mertens M, Janszky I, Ebner A, Woermann FG. Left-sided interictal epileptic activity induces shift of language lateralization in temporal lobe epilepsy: An fMRI study. Epilepsia [Internet] 2006; 47: 921-7
20 Powell HWR, Parker GJM, Alexander DC, Symms MR, Boulby PA, Wheeler-Kingshott CAM. et al. Abnormalities of language networks in temporal lobe epilepsy. NeuroImage 2007; 36: 209-21
21 Weber B, Wellmer J, Schür S, Dinkelacker V, Ruhlmann J, Mormann F. et al. Presurgical language fMRI in patients with drug-resistant epilepsy: Effects of task performance. Epilepsia 2006; 47: 880-6
22 Everts R, Simon Harvey A, Lillywhite L, Wrennall J, Abbott DF, Gonzalez L. et al. Language lateralization correlates with verbal memory performance in children with focal epilepsy. Epilepsia 2010; 51: 627-38
23 Miró J, Ripollés P, López-Barroso D, Vilà-Balló A, Juncadella M, de Diego-Balaguer R. et al. Atypical language organization in temporal lobe epilepsy revealed by a passive semantic paradigm. BMC Neurol 2014; 14: 98
24 Mbwana J, Berl MM, Ritzl EK, Rosenberger L, Mayo J, Weinstein S. et al. Limitations to the plasticity of language network reorganization in localization related epilepsy. Brain 2009; 132: 347-56