Mri Evaluation of Seizures: Study at a Tertiary Referral Center in Southern India

Abstract

Background: Epilepsy is a chronic entity with recurrent episodes of seizures. Estimated prevalence of epilepsy is about 5 to 10 persons per 1000 population and the incidence is about 0.3 to 0.5%. magnetic resonance imaging(MRI) is the imaging modality of choice in the evaluation of seizures because of its high soft tissue contrast and its capability of multi planar imaging. MRI is useful in the localization of epileptogenic focus precisely and to demonstrate its relation with eloquent areas of brain. Thus it helps in guiding the neurosurgeon in planning a surgery in cases of medically refractory epilepsy. The current study is undertaken to study the causative factors and the MRI findings in patients presenting with seizures. Subjects and Methods: The main source of data for the study are the patients with clinically suspected seizures referred for MRI to the Department of Radiodiagnosis at Katuri Medical College and hospital, Chinakondrupadu, Guntur. 60 patients referred to the Department of Radiodiagnosis for a period of 24 months with clinical symptoms and signs of seizures and referred for MRI examination were studied. Results: Maximum number of patients were in the age group of 1-30 years (63%). Maximum number of patients presented with GTCS. MR abnormality was maximum seen in patients between the ages of 16 to 45 years. Out of 60 patients who presented with seizures, in 28 patients (47%) the study was normal. Cerebrovascular causes including infarct with gliosis and venous thrombosis were found to be the most common diagnosis on MR imaging in patients presenting with seizures since it was seen in 10 patients (16%). Conclusion: Accurate detection of the underlying cause in seizure is very important for planning appropriate management. MRI is highly sensitive and specific in finding the pathology which   is responsible for seizures. In our study of 60 patients who clinically presented with seizures, infarct with gliosis, NCC, tuberculoma, atrophy, are the major etiological factors and others include venous thrombosis, developmental malformations, hypoxic ischemic injury, mesial temporal sclerosis, cavernoma, oligodendroglioma, meningioma and cerebral abscess. The commonest MR abnormality was cerebral infarct with gliosis. We conclude that MRI with seizure protocol plays a key role in the recognition of epileptogenic substrates and also for planning the management in patients with seizures and in predicting the prognosis.