Dealing with patients… jenny crinion adam liston

Dealing with patient’s data jenny crinion adam liston

SPM2 in Chalfont SPM2 in Queens Square Overview

SPM2 in Chalfont SPM2 in Queens Square Overview Epilepsy Pre-surgical – fMRI: avoid? (null hypothesis) / predict Pre-surgical – fMRI: avoid? (null hypothesis) / predict Lesions – advanced MRI techniques and VBM Lesions – advanced MRI techniques and VBM Psychosis – TLE with and without psychosis Psychosis – TLE with and without psychosis EEG-fMRI – focal and generalised epilepsy EEG-fMRI – focal and generalised epilepsy

Stroke Cross-sectional / longitudinal fMRI, DTI, TMS, VBM Cross-sectional / longitudinal fMRI, DTI, TMS, VBMDementia VBM and treatment studies with fMRI VBM and treatment studies with fMRI Overview Epilepsy Pre-surgical – fMRI: avoid? (null hypothesis) / predict Pre-surgical – fMRI: avoid? (null hypothesis) / predict Lesions – advanced MRI techniques and VBM Lesions – advanced MRI techniques and VBM Psychosis – TLE with and without psychosis Psychosis – TLE with and without psychosis EEG-fMRI – focal and generalised epilepsy EEG-fMRI – focal and generalised epilepsy SPM2 in Chalfont SPM2 in Queens Square

Anatomical - Lesions Advanced MRI techniques Voxel Based Morphometry (VBM) – SPM 99 Magnetisation Transfer (MTR), Fast Flair T2- (FFT2) and Double Inversion Recovery (DIR) imaging to identify abnormalities unseen in normal T1-weighted 2 nd level - template from 40 patients and 30 normals Concordance with EEG focus?? a b cd (a) Normalized axial T1-weighted, (b) MTR, (c) FFT2 maps (d) and DIR images. Frontal lobe epilepsy and normal conventional MRI:

Anatomical - Temporal Epilepsy Interictal psychosis (not related to seizure / years after onset of epilepsy) Optimised VBM – SPM99 study of schizophrenia (Good Neuroimage 2001) Led to study of interictal psychosis - MTR reductions specific to interictal psychosis? Brain (2001) 124,

75% fully controlled by medication Some of remainder may be eligible for surgery Cost? NULL hypothesis: fMRI - Presurgical Cognitive Experiments region is NOT active Presurgical Experiments region IS active

Temporal Lobe Epilepsy (TLE) Temporal Lobe Epilepsy (TLE) - resection of part of temporal lobe… fMRI - Presurgical Avoid eloquent cerebral areas: memory word generation verb generation reading SPM2 Analysis: patient-specific; block/event-related design Lateralisation

fMRI - Presurgical Predicted memory deficits: Medial Temporal Lobe (MTL) structures Lateralisation / localisation of memory function 10 normals, 8 patients with left TLE and 9 patients with right TLE 7 blocks of 10 pictures (P), 10 words (W) + 10 faces (F) pleasant? / unpleasant? Recognition tests of 210 stimuli foils recognise? (R) or new (N) 3 contrasts per subject (1) PR-minus-PN (2) WR-minus-WN (3) FR–minus-FN

3 contrasts per subject (1) PR-minus-PN (2) WR-minus-WN (3) FR–minus-FN 1 st level Pictures remembered

2 nd level Pictures remembered (controls) 2 nd level 2-way interaction: group (rTLE-lTLE) / memory

EEG-fMRI - focal epilepsy Problems Every case individual Bad experimental design – low efficiency: 0 to 638 events motion – jerks / scanner naivity drugs – cured(!) / effect on haemodynamic response function (hrf) effect of lesions on hrf

Motion

suspicious?

Scan nulling?

EEG-fMRI - generalised epilepsy Problems Syndrome: Idiopathic Generalised Epilepsy (IGE); secondary generalised “splitters” and “lumpers” Runs of 3Hz “spike-and-wave” Bad experimental design – low efficiency: events runs of 1 – 30 seconds (mean 2-3s) motion – jerks / scanner naivity drugs – cured(!) / effect on haemodynamic response function (hrf) effect of lesions on hrf

IGE SGE activation deactivation 60 events p<0.05 corrected 24 events p<0.05 corrected 57 events p<0.001 uncorrected 46 events p<0.05 corrected 2 nd level? Problems unbalanced valid grouping?