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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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