Dealing with patients… jenny crinion adam liston.
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Transcript of Dealing with patients… jenny crinion adam liston.
• SPM2 in Chalfont
• SPM2 in Queens Square
Overview
EpilepsyEpilepsy• Pre-surgicalPre-surgical – fMRI: – fMRI: avoid? (null hypothesis) / predictavoid? (null hypothesis) / predict• LesionsLesions – – advanced MRI techniques and VBMadvanced MRI techniques and VBM• PsychosisPsychosis – – TLE with and without psychosisTLE with and without psychosis• EEG-fMRIEEG-fMRI – – focal and generalised epilepsyfocal and generalised epilepsy
Stroke Stroke • Cross-sectional / longitudinalCross-sectional / longitudinal fMRI, DTI, fMRI, DTI,
TMS, VBMTMS, VBMDementiaDementia • VBM and treatment studies with fMRIVBM and treatment studies with fMRI
Overview
EpilepsyEpilepsy• Pre-surgicalPre-surgical – fMRI: – fMRI: avoid? (null hypothesis) / predictavoid? (null hypothesis) / predict• LesionsLesions – – advanced MRI techniques and VBMadvanced MRI techniques and VBM• PsychosisPsychosis – – TLE with and without psychosisTLE with and without psychosis• EEG-fMRIEEG-fMRI – – focal and generalised epilepsyfocal and generalised epilepsy
• SPM2 in Chalfont
• SPM2 in Queens Square
Anatomical - LesionsAdvanced MRI techniquesAdvanced 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
• 2nd level - template from 40 patients and 30 normals• Concordance with EEG focus??
a b c d
(a) Normalized axial T1-weighted, (b) MTR, (c) FFT2 maps (d) and DIR images.
Frontal lobe epilepsy and normal conventional MRI:
Anatomical - Temporal EpilepsyInterictal psychosis Interictal psychosis (not related to seizure / years after onset of epilepsy)(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 tointerictal psychosis?
Brain (2001) 124, 882-892
• 75% fully controlled by medication• Some of remainder may be eligible for surgery• Cost? NULL hypothesis:
fMRI - Presurgical
Cognitive ExperimentsCognitive Experiments region is NOT active
Presurgical ExperimentsPresurgical Experiments region IS active
Temporal Lobe Epilepsy (TLE)Temporal Lobe Epilepsy (TLE) - resection of part of temporal lobe…
fMRI - Presurgical
Avoid eloquent cerebral areas:Avoid eloquent cerebral areas:
memoryword generation
verb generation reading
• SPM2 Analysis: patient-specific; block/event-related design• Lateralisation
fMRI - PresurgicalPredicted memory deficits: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 of210 stimuli + 105 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
11stst level levelPictures rememberedPictures remembered
22ndnd level levelPictures remembered (controls)Pictures remembered (controls)
22ndnd level level2-way interaction: 2-way interaction: group (rTLE-lTLE) / memorygroup (rTLE-lTLE) / memory
EEG-fMRI - focal epilepsyProblemsProblems• 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
EEG-fMRI - generalised epilepsyProblemsProblems• Syndrome: Idiopathic Generalised Epilepsy (IGE); secondary generalised
“splitters” and “lumpers”• Runs of 3Hz “spike-and-wave”• Bad experimental design – low efficiency: 1 - 120 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