Cortical reorganization following anterior temporal lobectomy in patients with temporal lobe epilepsy.
BACKGROUND
Functional MRI was used to study the impact of temporal lobe epilepsy (TLE) and anterior temporal lobectomy (ATL) on the cortical language network in patients with medically refractory TLE.


METHODS
Nineteen patients with medically refractory TLE and 11 healthy control subjects were enrolled in this study. Ten patients underwent left ATL (mean age 35.2 +/- 3.8 years), and 9 underwent right ATL (mean age 35.9 +/- 2.6 years). The subjects silently generated verbs in response to a series of visually presented nouns inside the scanner. Correlation analysis was performed between the subjects' performance on the clinical language tests and their neural response in the a priori cortical regions.


RESULTS
Preoperative data revealed that the patients with TLE showed increased neural activity in the right inferior frontal gyri (IFG) and middle frontal gyri (MFG). The right TLE patients demonstrated strong correlation between their language performance and the level of cortical activation within the typical language areas. However, such a correlation was absent in the left TLE patients. After the ATL surgery, the left TLE patients showed reduced activation in the left MFG and right IFG, whereas no difference was observed in the right TLE patients. In the right TLE patients, the correlation between language performance and neural response shifted from the typical language areas to the anterior cingulate cortex.


CONCLUSIONS
This study demonstrates that the cortical language network is affected differently by the left and right temporal lobe epilepsy and is reorganized after anterior temporal lobectomy.
Wong
S W H
SW
Brain and Creativity Institute, University of Southern California, Los Angeles, USA.
Jong
L
L
Bandur
D
D
Bihari
F
F
Yen
Y-F
YF
Takahashi
A M
AM
Lee
D H
DH
Steven
D A
DA
Parrent
A G
AG
Pigott
S E
SE
Mirsattari
S M
SM
D000328:Adult; D001931:Brain Mapping; D004833:Epilepsy, Temporal Lobe / Q000150:complications* / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005625:Frontal Lobe / Q000033:anatomy & histology / Q000503:physiopathology; D007839:Functional Laterality / Q000502:physiology; D006179:Gyrus Cinguli / Q000033:anatomy & histology / Q000502:physiology; D006801:Humans; D007806:Language Disorders / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D007807:Language Tests; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000503:physiopathology / Q000601:surgery*; D009434:Neural Pathways / Q000033:anatomy & histology / Q000503:physiopathology; D009473:Neuronal Plasticity / Q000502:physiology*; D019635:Neurosurgical Procedures / Q000009:adverse effects / Q000379:methods; D020127:Recovery of Function / Q000502:physiology; D013060:Speech / Q000502:physiology; D013067:Speech Perception / Q000502:physiology; D013702:Temporal Lobe / Q000033:anatomy & histology / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome
J Neurosci. 1995 Feb;15(2):1090-8
7869085
Epilepsy Behav. 2005 Sep;7(2):273-8
16040279
Can J Neurol Sci. 1976 May;3(2):135-9
1268767
J Neurosci. 2007 Feb 28;27(9):2349-56
17329432
Can J Neurol Sci. 1974 Feb;1(1):7-16
4434266
Neuroimage. 2002 Jan;15(1):273-89
11771995
Epilepsia. 1989 Nov-Dec;30(6):763-71
2591343
Epilepsia. 2008 Aug;49(8):1377-94
18435753
Epilepsy Res. 2005 Aug-Sep;66(1-3):1-12
16118045
Cereb Cortex. 2007 Feb;17(2):443-56
16547345
Annu Rev Neurosci. 2002;25:151-88
12052907
Neurology. 2006 Mar 14;66(5):699-705
16534106
Epilepsia. 1998 Apr;39(4):407-19
9578031
Arch Neurol. 1996 Jan;53(1):72-6
8599562
Cereb Cortex. 1994 Jan-Feb;4(1):8-26
8180494
Neuropsychology. 1998 Apr;12(2):303-16
9556776
N Engl J Med. 2001 Aug 2;345(5):311-8
11484687
Trends Neurosci. 1994 Feb;17(2):75-9
7512772
Neuropsychology. 1999 Jan;13(1):3-9
10067770
Brain. 2001 Jun;124(Pt 6):1218-27
11353737
Neuropsychologia. 1971 Mar;9(1):97-113
5146491
Neurology. 1998 Nov;51(5):1243-4
9818838
Magn Reson Med. 2006 Feb;55(2):325-34
16408267
Epilepsia. 2001 Oct;42(10):1241-54
11737158
J Commun Disord. 1986 Dec;19(6):427-39
2433314
J Neurosci. 1995 Jan;15(1 Pt 1):12-29
7823123