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Neuroimaging studies play a fundamental role in the diagnosis and evaluation of epilepsy. Technological advances in neuroimaging techniques have made it possible to obtain functional as well as structural information. The pathophysiology of epilepsy consists of an abnormal increase in cerebral activity that can be appreciated on neuroimaging techniques like functional magnetic resonance imaging (fMRI), PET, and SPECT. In patients with epilepsy that is refractory to drug therapy, the main aim of surgery is to control seizures and thus to improve the quality of life. In the preoperative workup of these patients, fMRI has an increasingly important role, evaluating the location of functional areas that must be safeguarded during surgery.

Neuroimaging studies play a fundamental role in the diagnosis and evaluation of epilepsy. Technological advances in neuroimaging techniques have made it possible to obtain functional as well as structural information. The pathophysiology of epilepsy consists of an abnormal increase in cerebral activity that can be appreciated on neuroimaging techniques such as functional magnetic resonance imaging (fMRI), positron emission tomography (PET), and single-photon emission computed tomography (SPECT). In patients with epilepsy that is refractory to drug therapy, the main aim of surgery is to control seizures and thus to improve the quality of life. In the preoperative workup of these patients, fMRI has an increasingly important role, evaluating the location of functional areas that must be safeguarded during surgery. © 2010 SERAM. Published by Elsevier Espana, S.L. All rights reserved.

Resumen Introduccion El objetivo de este trabajo fue valorar la utilidad de la tomografia computarizada por emision monofotonica (SPECT) periictal para localizar la region epileptogena (RE) en pacientes con crisis parciales complejas (CPC) del lobulo temporal. Material y metodos De forma retrospectiva se ha evaluado a 37 pacientes con CPC del lobulo temporal a quienes se realizo una lobectomia temporal completa o selectiva. Para ello, se comparo la concordancia de la RE quirurgica con los hallazgos de la resonancia magnetica (RM), el videoelectroencefalograma (video-EEG) y las SPECT cerebrales interictal y periictal. En segundo lugar, se valoro el valor predictivo positivo (VPP) de estas exploraciones en los 29 pacientes que presentaron un buen control de las crisis tras la cirugia. La SPECT se realizo tras la inyeccion de 740 MBq de 99m Tc-HMPAO. Resultados La concordancia de la RE quirurgica con el video-EEG, la RM, la SPECT icterictal y la SPECT periictal fue del 86% (32/37 pacientes), el 84% (31/37 pacientes), el 54% (20/37 pacientes) y el 86% (32/37 pacientes), respectivamente. En los 11 casos con RM y video-EEG discordante o normal, la SPECT periictal fue decisivo en 8 (73%). En los 29 pacientes con evolucion favorable tras la cirugia, el VPP del video-EEG fue del 95% (27/29) y el de la RM y la SPECT periictal fue del 90% (26/29). Conclusiones La concordancia de la RE quirurgica con la SPECT periictal fue similar al del video-EEG y la RM y tuvo el mismo VPP que la RM. Por ello, creemos que la SPECT periictal debe emplearse de forma sistematica en la evaluacion prequirurgica de la epilepsia del lobulo temporal, especialmente cuando video-EEG y RM son discordantes o normales.

Introduction our aim was to evaluate the usefulness of peri-ictal SPECT in localising the epileptogenic region (ER) in candidates for temporal lobectomy to treat medically refractory complex partial seizures (CPS). Interictal and ictal SPECT, MRI and video-EEG results were compared and the positive predictive value (PPV) was calculated in those patients with good surgical outcome. Materials and methods 37 patients who had a minimum of 3 years follow-up after surgery were studied retrospectively. Pre-surgical evaluation had included video-EEG monitoring, MRI and interictal and ictal SPECT. These results were compared to the surgically treated ER and successful outcome confirmed by post-surgical clinical follow-up. 29/37 patients remained seizure-free in the post-surgical follow-up. Interictal and peri-ictal SPECT were performed using 740 MBq of 99mTc-HMPAO. Peri-ictal SPECT was ictal in 25 patients and postictal in 12. Results ER concordance with video-EEG and peri-ictal SPECT was 86% (32/37 patients). It was 84% (31/37) for MRI and 54% (20/37 patients) for interictal SPECT. Peri-ictal SPECT localised the ER in 8/11 patients with discordant MRI and video-EEG results. Ictal SPECT localised the ER in the correct temporal lobe in 23/25 patients (92% concordance). In the 29 patients with a good surgical outcome, the PPV of video-EEG was 95% (27/29) and it was 90% (26/29) for both MRI and peri-ictal SPECT. Conclusions peri-ictal brain SPECT is well able to localize ER in patients with temporal lobe epilepsy. Peri-ictal SPECT concordance with ER was as good as video-EEG and MRI and its PPV was as good as that of MRI. We strongly recommend its use in the pre-surgical evaluation of temporal lobe epilepsy, especially when MRI and EEG are discordant.

Neuroimaging studies play a fundamental role in the diagnosis and evaluation of epilepsy. Technological advances in neuroimaging techniques have made it possible to obtain functional as well as structural information. The pathophysiology of epilepsy consists of an abnormal increase in cerebral activity that can be appreciated on neuroimaging techniques like functional magnetic resonance imaging (fMRI), PET, and SPECT. In patients with epilepsy that is refractory to drug therapy, the main aim of surgery is to control seizures and thus to improve the quality of life. In the preoperative workup of these patients, fMRI has an increasingly important role, evaluating the location of functional areas that must be safeguarded during surgery.

A high percentage of subjects with cerebral palsy (CP) present brain injuries, which are revealed by neuroimaging techniques. On the whole the pattern of brain damage is heterogeneous.We review the studies that have described the brain damage in CP using structural and functional neuroimaging techniques. Brain damage is considered according to the type of CP and taking the gestational age into account.According to structural neuroimaging studies carried out in spastic diplegia, the brain pattern differs with the gestational age. In early subjects with spastic diplegia it is the periventricular white matter that is mainly affected. In spastic quadriplegia, cortico subcortical lesions and hypoplasia of the corpus callosum are also observed. Unilateral lesions predominate in the case of hemiplegia. Hemiplegic subjects may also present damage to the white matter, cortico subcortical lesions and congenital brain malformations. In these subjects, some of the injury patterns observed seem to be related with the clinical features they display. Dyskinetic CP is characterised by the absence of lesions and alteration of the basal ganglia and the thalamus. Very few studies have been conducted that take the different types of CP into account in comparing the findings of structural and functional neuroimaging.

Introduction A high percentage of subjects with cerebral palsy (CP) present brain injuries, which are revealed by neuroimaging techniques. On the whole the pattern of brain damage is heterogeneous. Development We review the studies that have described the brain damage in CP using structural and functional neuroimaging techniques. Brain damage is considered according to the type of CP and taking the gestational age into account. Conclusions According to structural neuroimaging studies carried out in spastic diplegia, the brain pattern differs with the gestational age. In early subjects with spastic diplegia it is the periventricular white matter that is mainly affected. In spastic quadriplegia, cortico subcortical lesions and hypoplasia of the corpus callosum are also observed. Unilateral lesions predominate in the case of hemiplegia. Hemiplegic subjects may also present damage to the white matter, cortico subcortical lesions and congenital brain malformations. In these subjects, some of the injury patterns observed seem to be related with the clinical features they display. Dyskinetic CP is characterised by the absence of lesions and alteration of the basal ganglia and the thalamus. Very few studies have been conducted that take the different types of CP into account in comparing the findings of structural and functional neuroimaging.

Introduction. Patients with drug-resistant epilepsy are potential candidates for surgery. The pre-surgical study of these patients involves a multidisciplinary approach. Patients and methods. We included patients who had been submitted to EEG-video monitoring in our centre (a tertiary university hospital) between April 1995 and May 2000 The evaluation protocol included magnetic resonance (MR) brain scan (according to a specific protocol), neuropsychological and psychiatric evaluation, and ictal/interictal SPECT, when possible. Patients who underwent surgery were followed up at regular intervals until at least two years after surgery. Results. Of the 299 patients with EEG-video monitoring, 87 had been submitted to surgery up to June 2000. Nine of these patients required invasive subdural studies or studies ofthe foramen ovale using electrodes. Of the patients who underwent surgery, 44.8% had sclerosis of the hippocampus in the MR and in 10% it was found to be normal. The results ofpathological anatomy revealed: 49.3% with sclerosis of the hippocampus, 15.1% with benign tumours, 13.7% with gliosis, 4.1% heterotopias and 4.1% cavernomas. Just one patient has been submitted to surgery again because of badly controlled seizures. Eight patients have presented post-surgical complications (four with permanent morbidity). Of the 73 patients who were followed up for at least a year, 83. 6% are in Engel class I, 9.6% in class II, 2. 7% in class III and 4.1% in class IV. Among patients who underwent a temporal resection, 88. 7% were in class I and 0% in class IV. Conclusions. Epilepsy surgery, in selected patients, has a very low morbidity/mortality rate and the chances that seizures will disappear or greatly improve are high.