Magnetic resonance spectroscopy and histopathological findings in temporal lobe epilepsy.
OBJECTIVE
In some patients with temporal lobe epilepsy, histopathological evaluation of resected brain tissue after surgical treatment may reveal several features indicative of discrete cortical malformations. We sought to determine whether these histopathological features were accompanied by hippocampal changes detectable preoperatively by proton magnetic resonance (MR) spectroscopy and to evaluate their relationship with postoperative outcome.


METHODS
In 25 consecutive temporal lobe epilepsy patients who were scheduled for surgical treatment, MR spectroscopy was performed, and resected brain tissue was analyzed histopathologically for the presence of discrete cortical malformations (e.g., microdysgenesis). Outcome was assessed in all patients with an average postoperative period of 26 months.


RESULTS
In 13 patients, we found subtle, histopathologically detectable signs of cortical malformation: 6 of them with concomitant hippocampal sclerosis (dual pathology) and 7 without. The latter subgroup had a worse surgical outcome and showed enhanced bilateral and/or contralateral pathological changes in the hippocampal formation when investigated by MR spectroscopy.


CONCLUSIONS
These data suggest that by showing contralaterally or bilaterally abnormal spectra, MR spectroscopy might be able to indicate pathological changes in subtle developmental disorders that are possibly more widespread over the brain. This observation may improve noninvasive diagnosis in presurgical evaluation and the neurobiological understanding of cortical malformations in pharmacoresistant temporal lobe epilepsy.
Stefan
H
H
Department of Neurology, University Erlangen-Nürnberg, Schwabachanlange 6, 90154 Erlangen, Germany. hermann.stefan@neuro.med.uni-erlangen.de
Feichtinger
M
M
Pauli
E
E
Schäfer
I
I
Eberhardt
K W
KW
Kasper
B S
BS
Hopp
P
P
Buchfelder
M
M
Huk
J
J
Paulus
W
W
D000328:Adult; D004833:Epilepsy, Temporal Lobe / Q000175:diagnosis* / Q000473:pathology* / Q000601:surgery; D005260:Female; D007839:Functional Laterality; D006624:Hippocampus / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data; D009682:Magnetic Resonance Spectroscopy / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D012598:Sclerosis / Q000175:diagnosis / Q000473:pathology; D013702:Temporal Lobe / Q000002:abnormalities / Q000473:pathology* / Q000601:surgery; D016896:Treatment Outcome