Correlating 3T MRI and histopathology in patients undergoing epilepsy surgery.
OBJECTIVE
To investigate whether specific semi-quantitative 3T MRI parameters are associated with particular histological features in temporal lobe specimens in epilepsy surgery patients whose conventional MRI scan appeared normal. These MRI techniques have the potential to visualise subtle structural abnormalities currently undetected on conventional MRI; but correlation between pre-operative in vivo MRI and histopathology is needed to understand the basis of these MRI abnormalities. Predicting subtle histopathology with semi-quantitative MRI techniques could contribute to pre-surgical evaluation of epilepsy patients.


METHODS
MRI techniques: normalised FLAIR signal intensity (nFSI), grey matter probability and diffusion tensor imaging (DTI) were correlated with quantitative histopathological measures: NeuN (neuronal nuclear antigen); GFAP (glial fibrillary acidic protein) and MBP (myelin basic protein) field fractions and stereological neuronal densities obtained in grey and white matter regions in twenty-four patients who underwent anterior temporal lobe resections.


RESULTS
There were no significant correlations between the histopathological measurements and MRI values in grey or white matter in macroscopically normal appearing tissue.


CONCLUSIONS
Findings suggest that in macroscopically normal appearing tissue, the studied semiquantitative MRI measurements are not significantly related to the measures of gliosis, neuronal loss/gain and myelin used in the current study. Studies of macroscopically abnormal tissue as well as improvements to the MRI techniques may increase the sensitivity of future correlative studies to improve our understanding of the histopathological basis of MRI signal characteristics.
Department of Clinical and Experimental Epilepsy, Institute of Neurology, UCL, London WC1N 3BG, UK. g.lockwood-estrin10@csc.mrc.ac.uk
Georgia
G
Lockwood-Estrin
Maria
M
Thom
Niels K
NK
Focke
Mark R
MR
Symms
Lillian
L
Martinian
Sanjay M
SM
Sisodiya
John S
JS
Duncan
Sofia H
SH
Eriksson
D000328:Adult; D034961:Antigens, Nuclear / Q000378:metabolism; D015415:Biomarkers; D001923:Brain Chemistry / Q000502:physiology; D002540:Cerebral Cortex / Q000473:pathology*; D056324:Diffusion Tensor Imaging; D004833:Epilepsy, Temporal Lobe / Q000473:pathology* / Q000601:surgery*; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D005911:Gliosis / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000706:statistics & numerical data; D008297:Male; D054220:Malformations of Cortical Development / Q000473:pathology; D008875:Middle Aged; D004676:Myelin Basic Protein / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism; D019635:Neurosurgical Procedures; D013702:Temporal Lobe / Q000473:pathology / Q000601:surgery; D055815:Young Adult
D034961:Antigens, Nuclear; D015415:Biomarkers; D005904:Glial Fibrillary Acidic Protein; D004676:Myelin Basic Protein; D009419:Nerve Tissue Proteins; C506808:neuronal nuclear antigen NeuN, human