A seizure is an occurrence of signs or symptoms due to abnormal excessive or synchronous neuronal activity in the brain. When the above is associated with motor components then they are known as convulsions. Epilepsy is a condition characterized by recurrent (two or more) unprovoked seizures occurring 24 hours apart. [1]. Seizures are common in the pediatric age group and occur in 10% of children. Less than 1/3rd of seizures in children are caused by epilepsy. [2]. The etiological spectrum of acute symptomatic seizures in developing countries is different from developed countries. In developing countries like India, intracranial infections still constitute the single largest cause of childhood seizures. [3-5]. The tremendous advances in neuro-radiological investigations and electroencephalogram (EEG) have resulted in a series of noninvasive diagnostic procedures. However, it is not always that the information derived from these investigations changes the line of management and there is always a concern regarding cost and radiation exposure. [6,7].

Hence it is essential to evolve a method to identify children with symptomatic epilepsy by clinical criteria so that seizures are better managed and expensive investigations can be judiciously used. The present study aims to study the etiological factors and clinical profile for new-onset seizures in children aged 6-12 years and to determine the frequency of MRI abnormalities in the pediatrics age group with new-onset unprovoked seizure and those with inadequately investigated longstanding epilepsy and classify the etiology based on the MRI findings.

A prospective study involving pediatric patients presenting with new-onset, recurrent and refractory seizures to the pediatric department was done. A total of 50 patients were recruited aged between 6 to 12 years. Following evaluation by a pediatrician and a neurologist, all these patients underwent appropriate investigations. All of them underwent neuro-imaging with MRI. Uncooperative patients were imaged following sedation and monitoring by the anesthetist.

Inclusion criteria: All children aged 6-12 years who presented with new-onset seizures were included.

Table 2: Correlation of type of seizure with Positive findings

Table 3: Cause of epilepsy in the order of prevalence

Table 4: MRI study

Figure 1: T2W sagittal image showing prominent perivascular spaces in the corpus callosum.

ILAE etiological classification has six categories namely structural, genetic, infectious, metabolic, immunological, and unknown. In our study etiological classification of epilepsy in the pediatric age group (6-12years) based on MRI findings in 50 patients was evaluated. Epilepsy has a significant psychosocial and financial burden on society in developing countries. The advent of MRI has revolutionized the evaluation and management of seizures. In our research, we studied the role of MRI in identifying subtle and gross anatomical /structural pathologies that are instrumental in causing epilepsy. MRI was preferred over CT scan in our study due to lack of ionizing radiation and excellent soft-tissue contrast allowing the detailed depiction of anatomy with precision.

Our study population consisted of 56% of patients who had presented with a history of generalized tonic-clonic seizures. Thus a majority of the patients presenting with generalized seizure is in tune with other studies conducted in developing countries. In the present study, generalized tonic-clonic seizures (GTCS) were the most common type seen in 56% followed by complex partial seizures (CPS) in 20%, simple partial seizures (SPS) in 24%. Another study by Saha SP et al concluded that simple partial seizures constituted 10.5% of total seizures, complex partial constituted 21.1% of total seizures. [8]

In a study made by Singhi S et al, seizures were partial complex in 65% and simple partial in 35%. [9] Present results are comparable with these studies. We found positive MRI findings in 56% of the patients presenting with seizures. Our study had a relatively higher percentage of positive findings because of inclusion criteria of patients presenting with a minimum of 2 episodes of seizure. The patients visiting our hospital are from the rural background, who visits the hospital only when they are seriously ill. In our study population, 60% of the patients had a previous history of multiple episodes of seizures.

The other reason could also be due to the high resolution 1.5 tesla MRI scanner used. In our study structural abnormality could not be detected in 45.6% of patients. Among these 55% had presented with generalized tonic-clonic seizures. Hence cases with generalized tonic-clonic seizures constituted maximum to the cryptogenic cause. The most common cause of seizure based on MRI findings in our study was found to be cryptogenic.

Other characteristics include focal cortical thickening and blurring of grey-white matter junction. Two cases of infectious origin were reported. One was a case of tuberculoma. We reported 2% of metabolic storage disorders. One of them was metachromatic leukodystrophy demonstrating bilateral confluent areas of high signal intensities in per ventricular white matter and sparing of U-fibres in T2 weighted imaging.

The three other cases were mucopolysaccharidosis which had J-shaped sella, prominent perivascular spaces, and white matter intensities on T2 weighted imaging. In our present study (n=50) we had 54% positive findings in MRI as our study population was opted between 6- 12 years mostly to exclude febrile seizures. Hence with this, our study implies the importance of imaging in seizures even in the pediatric age group.

As we do not have many Indian studies done with MRI imaging we have compared with CT scan studies to impact the importance of imaging in the seizure in children. A study done by Kanitkar M et al concluded that CT scan abnormality was detected in 66% of cases. [10]. Single or multiple tuberculomas were noted in 24% cases, cortical atrophy in 14% cases, focal calcification in 10%, hemorrhage in 3%, and subdural effusions in 2%.

In a study done by Baheti R et al, 50% of children with partial seizure and 35% of children with generalized seizure had abnormal CT findings. [11]. Jagar H et al observed abnormal CT findings in 68% of children with partial seizures. [12]. Shinnar S et al observed 21% of children had abnormalities; focal encephalomalacia and cerebral dysgenesis were the most common abnormality. [13].

Berg AT et al observed abnormality in 12.7% of those imaged. [14]. Misra S et al observed CT Brain was abnormal in 75% of children with the seizure disorder, the ring-enhancing lesion was the commonest abnormality (54%) followed by brain atrophy. [15].

Generalized seizures were a more common presentation than partial seizures in children 6-12 years of age. Positivity of the MRI in the new-onset seizure in children between 6-12 years in our study emphasizes the importance of imaging in pediatric new-onset seizures.