Role of Magnectic Resonance Imaging of Brain in Paediatric Patients with Partial Seizures

Seizures are common neurologic problem in all age groups attending neurological units of large urban teaching hospitals; occur in approximately 10% of children. Presence of seizures constitutes a symptom of an underlying central nervous system disorder that requires thorough investigations and management plan. Epileptic seizures are caused by cerebrocortic al hyperactivity , partial onset seizures begin in localized area of cerebral cortex. Less than one third of the seizures in children are caused by epilepsy, a condition in which seizures are triggered recurrently from within brain(1). Lesions in temporal lobe are probably most likely to cause seizures. Till date the classification proposed by International League against Epilepsy is most widely accepted and gives important guidelines in determining prognosis and predicting response to treatment. The etiological factors of epilepsy differ markedly in children as compared to adults. Partial seizures account for a large proportion of childhood seizures, up to 40% in some series. Classified as simple and complex, consciousness is maintained with simple partial seizures. Common causes include inflammatory granulomas, atrophic lesions, birth asphyxia, head trauma and neoplasm. Neurocysticerosis has emerged as a common cause in India. Neurocutaneous syndromes, arteriovenous malformations and infarcts are less frequent (2). The relationship of origin of a focal seizure, the epileptogenic focus to a structural lesion is based on three assumptions: Partial seizures are due to pathologic abnormality thus there is always a lesion, if a lesion can be shown in a patient with seizures then it is highly probable that seizures are the result of that lesion and the seizures focus originates in the vicinity of the lesion, but precise site and the extent of focus is not necessarily the same as that of the lesion. Recently, there are many investigations and modalities available for diagnosis and searching for cause of seizures such as EEG , CT scan, MRI, SPECT as well as PET . But introduction of MRI into clinical practice during the