RESUMO
BACKGROUND: The reasons for surgical failure in 30% of patients with unilateral mesial temporal lobe epilepsy (MTLE) are still unclear. We investigated if different outcomes could be associated to different patterns of subtle gray matter atrophy (GMA) and white matter atrophy (WMA), and searched for postoperative magnetic resonance imaging (MRI) changes. METHODS: We studied 69 controls and 67 operated patients with refractory unilateral MTLE. Patients were grouped as seizure-free (SF) group (34 patients Engel's IA), worthwhile improvement group (23 patients, Engel's IB-IIA) and failure group (10 patients Engel's IIB-IV). We created a voxel-based morphometry/MATLAB code to mask the surgical lacuna, and performed t-test and paired t-test to evaluate preoperative and postoperative MRI scans. RESULTS: Failure group showed a widespread pattern of preoperative GMA. On SF and improvement groups we identified a more restricted pattern of GMA. The three groups presented a widespread, bilateral pattern of WMA. In contrast, postoperative analyses showed bilateral hemispheric recovery (a relative increase of WM concentration) on SF and improvement groups, but few changes on failure group. We also identified areas with relative postoperative increase of GM on both SF and improvement groups, more widespread on SF group. CONCLUSION: Areas of subtle GMA may be related to poorer surgical outcome. In addition, we demonstrated a postoperative relative increase of WM and GM concentration associated with seizure control. These changes may represent neuroplasticity related to improvement of brain function after seizure control. Further studies with a multimodal approach may help to predict surgical outcome and improve selection of patients for surgical treatment of MTLE.
Assuntos
Encéfalo/patologia , Encéfalo/cirurgia , Epilepsia do Lobo Temporal/patologia , Epilepsia do Lobo Temporal/cirurgia , Procedimentos Neurocirúrgicos , Adulto , Encéfalo/diagnóstico por imagem , Eletroencefalografia , Epilepsia do Lobo Temporal/diagnóstico por imagem , Feminino , Fluordesoxiglucose F18 , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , Complicações Pós-Operatórias/patologia , Período Pós-Operatório , Convulsões/patologia , Convulsões/cirurgia , Resultado do TratamentoRESUMO
OBJECTIVES: To study pre and postoperative WMA in MTLE patients. METHODS: We performed Voxel-Based Morphometry (VBM) with volume of interest (VOI) in 69 controls (mean age, 34.3±11.1 years) and 67 operated patients (mean age, 34.1±10.4 years) with unilateral MTLE. 34 became seizure-free (SzFree-Group), 23 improved (Engel IB-IIA [Partial recovery-group]) and 10 did not improve (Engel III-IV [Failure-Group]). All had pre and postoperative MRIs (one year minimum). We flipped MRIs of right MTLE patients in order to avoid right-to-left analysis cancelation. VBM was performed on SPM2/MATLAB7.0 with individual masks for surgical lacunae and 1 percent false-discovery-rate to control for multiple comparisons. We used MARSbar