Abstracts

Rationale:
Refractory epilepsy is one of the most challenging disorders in Neurology. Patients do not show a good response to antiepileptic drug therapy, and in many of them standard image techniques (magnetic resonance imaging; MRI) do not allow an early identification of a lesion. Also, in those patients, only after surgery, the etiology is found on histopathology. We describe the clinical features, treatment, images and histopathological findings and outcomes of three patients with non-lesional epilepsy and one patient with an unclear lesion, treated in a neurological specialized hospital in Perú.
Method:
Four patients with the diagnosis of refractory epilepsy were followed at a neurological specialized hospital in Lima, Perú. The patients had presented with high frequency focal cognitive seizures and they had received multiple treatment schemes without a good response. Three of them had been through standard magnetic resonance imaging (MRI) epilepsy protocols without relevant findings, although video-electroencephalography tests showed focal epileptic activity and on interictal positrons emission tomography (PET) focal areas of hypometabolism where found. Standard MRI performed to the fourth patient showed areas of periventricular heterotopia not related to the seizure semiology. The patients were assessed by an Epilepsy Surgery Committee and afterwards more imaging and functional studies were performed and finally they were declared candidates for epilepsy surgery.
Results:
In three of the patients with non-lesional epilepsy (defined by absence of lesions on standard MRI epilepsy protocols) there were relevant findings on interictal PET and video-electroencephalography studies. After surgery they experienced improvement in the frequency and duration of seizures. The patient who showed areas of heterotopia on standard MRI did not experienced any improvement of the seizures after surgery.
Conclusion:
Three of four patients with the diagnosis of refractory epilepsy who were studied on an Epilepsy Center in Perú experienced clinical improvement after Epilepsy surgery. Histopathology showed cortical dysplasia in one of them. There were no histopathological findings in the other two patients. The fourth patient had showed periventricular heterotopia on standard MRI images but because of the severity of the seizures, surgery was performed, although her symptoms did not improve after surgery.  Nowadays, Epilepsy surgery has become a very important option in the treatment of patients with refractory epilepsy. It is important to remark the role of the multidisciplinary team in the definition of the best surgical hypothesis in order to improve the quality of the outcomes.
Funding:
:None.