RESUMEN
INTRODUCTION: Mesial temporal sclerosis (MTS) is defined as neuron loss and gliosis in the hippocampus and adjacent structures. Here we report on our 19 years' experience in dealing with this condition. PATIENTS AND METHODS: A retrospective, descriptive study was conducted of patients diagnosed with MTS between May 1990 and January 2009. RESULTS: A diagnosis of MTS was established in 16 cases (62.5% males). By location these cases were distributed as follows: 12 were unilateral (seven left temporal and five right) and four were bilateral. It was associated to cortical dysplasia in six patients (37.5%) and to hippocampal arachnoid cysts in two other cases. As regards possible causations, in one case herpes simplex encephalitis was suspected; in three cases, a prenatal cerebral vascular pathology; and in three others, prenatal infection by cytomegalovirus. The distribution of the clinical spectrum was as follows: five patients with isolated clinical epilepsy; one with isolated psychomotor retardation or mental retardation (PMR-MR); one with isolated autism spectrum disorder (ASD); three with epilepsy associated to PMR-MR; one with epilepsy associated to ASD; two with PMR-MR and ASD; and two with the triad consisting of epilepsy together with PMR-MR and ASD. In one case, MTS was discovered in migraine studies, without any other symptoms. Crises were controlled with monotherapy in all the patients who received antiepileptic treatment except in three, one of whom required surgery. CONCLUSIONS: The definitive diagnosis of MTS is pathologic, but the latest neuroimaging techniques have allowed a very reliable approximate diagnosis to be reached. It may be associated to other malformative disorders, such as focal cortical dysplasia or cysts. MTS can be observed in epilepsy (whether refractory or not), but also in ASD, PMR-MR or asymptomatic patients.