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Imaging in Epilepsy
• computerised tomography (CT)
• magnetic resonance imaging (MRI)- anatomical MRI- functional MRI
• positron emission tomography (PET)
• single-photon emission computed tomography (SPECT)
Indications for MRI in Epilepsy
• non-idiopathic epilepsies
• normal or non-idiopathic EEG change (no GSW, CTS)
• associated neurological abnormalities
• suspected cerebral pathology from history/exam
• worsening epilepsy
Epileptogenic Lesions
Focal lesions• hippocampal sclerosis• developmental tumours and hamartomas• focal cortical dysplasias• cavernous and other vascular malformations• focal traumatic, infective or ischaemic lesions
Bilateral, multifocal and diffuse lesions• tuberous sclerosis• major cerebral malformations• extensive traumatic, infective or ischaemic lesions
Focal Epileptogenic Lesions
focal cortical dysplasia
encephalomalaciahypothalamic hamartoma
hippocampal sclerosis gangliogliomadysembryoplastic NET
focal cortical dysplasia
thin (100 slices) FSPGR acquisition in tilted axial plane thin (100 slices) FSPGR acquisition in tilted axial plane
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Epileptogenic Lesions
Focal lesions• hippocampal sclerosis• developmental tumours and hamartomas• focal cortical dysplasias• cavernous and other vascular malformations• focal traumatic, infective or ischaemic lesions
Bilateral, multifocal and diffuse lesions• tuberous sclerosis• major cerebral malformations• extensive traumatic, infective or ischaemic lesions
Major Cerebral Malformations
hemimegalencephaly polymicrogyria schizencephaly hemidysplasia
agyria / pachygyriadiffuse heterotopiatuberous sclerosismeningeal angiomatosis
MRI
PET
Ictal SPECT
axial sagittal coronal
structure function biochemistry
High Field Magnetic Resonance Imaging
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Noun verb
Laterality index: 0.483
Indications for MRI in Epilepsy
• non-idiopathic epilepsies
• normal or non-idiopathic EEG change (no GSW, CTS)
• associated neurological abnormalities
• suspected cerebral pathology from history/exam
• worsening epilepsy
hippocampal sclerosis
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dysembryoplastic neuroepithelial tumour
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ganglioglioma
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hypothalamic hamartomas
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focal cortical dysplasia
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focal atrophy / encephalomalcaia
prenatal MCA infarct orbitofrontal contusion HSV encephalitis
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hemimegalencephaly
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polymicrogyria
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schizencephaly
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hemidysplasia
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meningeal angiomatosis (Sturge Weber)
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tuberous sclerosis
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diffuse heterotopia
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periventricular nodular heterotopia subcortical band heterotopia“double cortex”
agyria / pachygyria
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