Paediatric Epilepsy Flashcards
What is epilepsy?
A symptom - a chronic neurological condition characterised by recurrent epileptic seizures
Why is epilepsy a common condition?
Prevalence of 0.5%
It is not a single condition - it is symptom of many different diseases
Can be difficult to diagnose
No single treatment
Why is epilepsy misdiagnosis rate high?
- There is no diagnostic test
2. The diagnosis is made predominantly on clinical history description of events
What is the percentage that the epilepsy is resistant to medication?
25%
More likely if lesional
What is an option if there is localised onset to seizures in epilepsy?
Surgical treatment
Define where the seizure onset is
What does imaging of childhood epilepsy consist of?
- Pathological substrate
- Source of epileptic seizures
- Localisation of function
- Secondary effects of epilepsy
- Underlying pathophysiology
What is pathological substrate concerned with?
The cause of epilepsy
Magnetic resonance imaging
What are examples of source of epileptic seizures?
- SPECT
- PET
- MRI
What is MRI concerned with?
Localisation of function
Underlying pathophysiology
What is PET and MRI concerned with?
Secondary effects of epilepsy
What is key in magnetic resonance imaging in childhood epilepsy?
- Malformation cortical development
2. Cortical grey matter
What is band heterotopia?
Also known as double cortex syndrome is a form of diffuse grey matter heterotopia affecting almost only women
More lateralised abnormalities
What is Hemimegalencephaly (HME)?
A rare neurological condition in which one half of the brain, or one side of the brain is abnormally larger than the other
What are examples of HME?
- Dysplasia
- Polymicrogyria
- Multifocal dysplasia
- Benign tumours
What is lissencephaly?
Smooth brain
Is a set of rare brain disorders where the whole or parts of the surface of the brain appear smooth - it is caused by defective neuronal migration during the 12th to 24fh weeks of gestation resulting in a lack of development of brain folds (gyri) and grooves (sulci)
What are the optional sequences ?
- Susceptibility weighted images
- Diffusion tensor imaging
- Arterial spin labelling (perfusion)
Why do we have to optimise the grey-white differentiation?
Look specifically at the grey matter
What is also needed to be optimised?
Angle of sequences is important
- straight horizontal/vertical - poor views of temporal lives
- we want to angle our sequences parallel or perpendicular to the axes of temporal lobes
Get food view and avoid partial volume effects particularly with the mesen-temporal structures
What shows abnormalities particularly in grey matter?
FLAIR
What is the timing of scan and maturation?
Very early in 2 years of life - slightly different sequences are required because myelination is incomplete
Lesions May appear or disappear with myelination and therefore repeating imaging are therefore necessary
It is not a waste of time to do imaging in the first 2 years of life because you may see an abnormality that may subsequently become less apparent as they become older
Compare images - early and late life in early onset epilepsy
What are the MRI findings?
- 26 (51%) aetiologically relevant abnormalities
2. 11 (21%) non specific structural abnormalities
What are examples of 11 developmental malformations?
- 2 Tuberous sclerosis
- 2 Lobar/ multilobar focal cortical dysplasia
- 3 bilateral polymicrogyria ( 1 with cerebellar hypoplasia)
- 1 Hemimegalencephaly (+ bilateral polymicrogyria )
- 1 Microcephaly, absent corpus callosum
- 1 LisdencephAly
- 1 Occipital AVM
What are the 15 acquired lesions?
14- secondary to infection, HIE, metabolic conditions, seizures
1 a probably MTS
What are non-specific structural abnormalities?
Lack of white matter bulk, thin corpus callosum, delayed myelination, arachnoid cyst
