SPECTRUM OF ABNORMALITIES DETECTED ON MRI IN 250 CASES OF FOCAL EPILEPSY IN A TERTIARY CARE HOSPITAL

BACKGROUND AND OBJECTIVES: The accurate diagnosis of the cause of the seizure is crucial for treatment and prognosis. MRI not only identifies specific epileptogenic substrates, but it has also increased substantially the ability to detect causes of seizure and to plan medical or surgical therapy. The aim of this study was to evaluate the role of MRI in detection, localization and characterization of the structural epileptogenic abnormalities in focal epilepsy. Materials and methods: prospective study was done on 250 patients (138 males and 112 females) of all the ages, with focal seizures presenting in OPD or IPD with exclusion of idiopathic generalized epilepsy, acute head trauma, febrile seizures, and acute infarct/haemorrhage cases. The study was done on 1.5 Tesla MRI using various protocols. Routine investigations [(Haemoglobin (HB), total leukocyte count (TLC) differential leukocyte count (DLC) and erythrocyte sedimentation rate (ESR)] were done in all the patients. Cerebrospinal fluid (CSF) and histopathological analysis were taken into account wherever available. Results: MRI showed normal study in 108 cases (43.2%), 58 cases (23.2%) of neuroinfection, 39 cases (15.6%) of gliosis, 25 cases (10%) of neoplasms, 15 cases (6%) of developmental anomalies, two cases (0.8%) each of Rasmussen encephalitis and hypoxic ischaemic encephalopathy and one case (0.4%) of vascular anomaly. Conclusion: CNS granulomatous pathology (predominantly NCC) and gliosis / encephalomalacia were the two most common abnormalities detected on MRI. Majority of structural epileptogenic abnormalities are detected by MRI making it a superior neuroimaging modality with no radiation exposure and higher sensitivity but subtle abnormalities are missed giving false negative results therefore employing appropriate imaging protocols and performing dedicated pulse sequences is essential.