Learning objectives
- To discuss the role of the advanced MRI techniques (diffusion-weighted imaging, MR spectroscopy, diffusion tensor imaging, susceptibility weighted imaging, functional MRI and arterial spin labelling) in the diagnosis of the underlying process of the seizures.- To describe the advantages of 3.0-T imaging in the study of pediatric epilepsy.- To illustrate the spectrum of abnormalities involved in the pathogenesis of epilepsy in childhood.
Background
Epilepsy is a common disorder, with a prevalence of 0.4% to 1% of the population.MR imaging is an excellent tool for detecting anatomic substrates that underlie regional brain epileptogenesis. MRI is the technique of choice for investigation of patients with seizure disorders.CT uses ionizing radiations so it should be performed in children only in emergency situations, if MRI is not readily available or if there are contraindications to MRI.When neuroimaging is needed?- Focal onset of seizures.- Onset of generalised or unclassified seizures in the first...
Imaging findings OR Procedure details
What’s new?Diffusion weighted imaging (DWI)Prolonged seizures and status epilepticus can cause cytotoxic and vasogenic edema in the epileptogenic area.DWI can identify differences in the variation of molecular water mobility in extracellular spaces delineating focal areas of cytotoxic edema.DWI is useful in identifying not only the epileptogenic zone and the subcortical areas of propagation. Hippocampal formation, pulvinar thalamic nuclei, cortical regions and splenium of corpus callosum are the areas involved more frequently (Fig.1).MRI repeated several weeks after remission of seizures will reveal complete resolution of the...
Conclusion
Application of advanced new MRI techniques promises to improve the detection of the substrates of epilepsy and therefore to reach a better therapy of seizures.3.0-T MR imaging acquires thin-section high-resolution images that increase lesions conspicuity and provides, in our experience, a better visualization of some subtle conditions, such as hippocampal anomalies or cortical dysplasia.
Personal Information
Ignacio Delgado
[email protected] Materno-Infantil Vall d'Hebron & IDI.Universitat Autónoma de Barcelona.Pediatric Radiology Department.Passeig Vall d'Hebron 119-12908035 BARCELONASPAIN
References
EpilepsyDuncan JS. Neuroimaging Clinics of North America – Epilepsy. Philadelphia. North America: Elsevier; 2004.Commission on Neuroimaging of the International League Against Epilepsy. Recommendations for neuroimaging of patients with epilepsy. Epilepsia. 1997; 38: 1255–6.Salmenpera TM, Duncan JS. Imaging in epilepsy. J Neurol Neurosurg Psychiatry. 2005 Sep;76 Suppl 3:iii2-iii10.Rastogi S, Lee C, Salamon N. Neuroimaging in pediatric epilepsy: a multimodality approach.Radiographics. 2008 Jul-Aug;28(4):1079-95.Wright NB. Imaging in epilepsy: a paediatric perspective. Br J Radiol. 2001; 74: 575–89.Vazquez E, Mayolas N. Developmental abnormalities of temporal lobe in children. Semin...
