Single enhancing CT lesions in Indian patients with seizures: clinical and radiological evaluation and follow-up.

Single enhancing lesions in cranial computed tomography (CT) are the commonest imaging abnormality in Indian patients with seizures. We studied 101 such patients who had single CT lesions at least 6 months prior to enrollment in the study. A repeat CT scan was performed in each case after enrollment in the study. The majority of patients were below 10 years of age. Simple partial tonic/ clonic convulsions were the commonest type of seizure encountered irrespective of location of the CT lesion. The parietal lobe was the commonest site of location. All patients with a parasagittal location of the lesion had Todd's palsy. All patients had an acute seizure episode or a cluster of seizures (multiple within 24 h). Ten patients presented with simple partial status epilepticus as first seizure. The initial non-contrast enhanced CT scan revealed focal hypodensity due to cerebral oedema in 49 patients. In an additional 17 patients we observed complete cysticercal larvae (cyst with scolex). In the rest of the patients, plain CT scans were normal. After contrast administration, the majority revealed a ring/disc enhancing lesion; half of them had an enhancing eccentric dot representing a scolex. Forty-seven patients received definitive treatment in the form of either albendazole or antituberculous drugs along with antiepileptic drugs. The rest of the patients received only antiepileptic monotherapy. The majority of patients, irrespective of type of treatment, showed either regression or disappearance of lesions. Similar incidences of seizure recurrences were noted in patients who themselves discontinued antiepileptic therapy, in comparison to those who continued with antiepileptic drugs. Only nine out of 16 patients with persistent CT lesions experienced recurrence of seizures. In the majority, persisting lesions remained unchanged to a ring form; in the remaining patients ring lesions transformed into disc-enhancing lesions, or became calcified. In conclusion, these CT lesions are benign in nature and tend to disappear or regress spontaneously. The associated seizure disorder is also benign and easily controlled. Probably, a shorter duration of antiepileptic therapy would suffice. Neither albendazole nor antituberculous therapy was helpful in modifying the natural course of the CT lesion or associated seizure disorder.