Regeneração de atrofia de substância branca após a cirurgia de epilesia: evidências estruturais através da morfometria baseada em voxel / Recovery of white matter atrophy after epilepsy surgery: structural evidences through voxel-based morphometry

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 routine to select ROIs and t-test for statistical analyses. RESULTS: Mean postoperative follow-up was 60.2 (±SD 30.7) months. On baseline MRI, SzFree-Group showed White Matter Atrophy (WMA) involving temporal lobes [TL], ipsilateral occipital, parietal and frontal regions, with areas of significant recovery of WMA on postoperative MRI. Partial recovery-Group presented a more restricted pattern of WMA, involving ipsilateral temporal lobe, contralateral superior temporal gyrus and few areas in bilateral cingulated and orbitofrontal areas. In this group we also identified areas with relative increase of WM after surgery. By contrast, Failure-Group showed more widespread bi-hemispheric areas of WMA on baseline MRI without postoperative improvement. CONCLUSIONS: Although we have identified some differences in baseline WMA, we were unable to correlate a more widespread pattern with a worse prognosis, as SzFree-Group, also presented a bilateral distribution of WMA. The recovery of WMA in SzFree-Group and Partial recovery-group is in agreement with previous MRS and PET studies and suggests that a network of neuronal dysfunction in MTLE can be, at least in part, reversible after successful postoperative ...

Avaliação computacional da impressão plantar. Valores de referência do índice do arco em amostra da população brasileira / Computational evaluation of the footprint. Reference values of the plantar arch index in a sample of the Brazilian population

A presença do arco longitudinal medial (ALM) é característica dos pés humanos e através dele o pé tem sido classificado como normal, cavo e plano. A literatura permite escolher entre variados métodos e técnicas de mensuração do ALM, cada qual com vantagens e desvantagens. Optou-se pelo método da impressão plantar com medida do índice do arco (IA) para avaliar indiretamente a altura do ALM. A escolha foi motivada por ser a impressão plantar exeqüível com baixo custo e não invasiva. Seguiu-se o princípio básico do método de mensuração do IA proposto por Cavanagh & Rodgers, modificado pela introdução do escaneamento da impressão plantar e pelo cálculo do IA através de programa computacional elaborado por um dos autores. Foram avaliadas 100 impressões plantares de 25 homens e 25 mulheres sadios, não obesos, com média de idade de 34,7 anos, extremos de 10 a 59 anos. Obtiveram-se os valores de referência do IA de amostra da população brasileira: 0,21< IA < 0,25. A comparação estatística dos valores nacionais com os da amostra americana não mostrou diferença estatística significativa.

The presence of medial longitudinal arch (MLA) is characteristic of the human feet and has been used for the classification of a normal, cavus and flat foot. The literature provides informations about several methods and different techniques of measurement the MLA, each one having advantage and disadvantage. We choose the footprint method and the measuring of arch index (AI) as an indirect evaluation of the MLA height. We preferred this method because it is simple, cost-effective and noninvasive. We followed the basic principles of the IA measurement proposed by Cavanagh & Rodgers, but modified because we introduced footprint scan and AI calculation using a software program elaborated by one of the authors. A total of 100 footprints were analyzed in healthy, non obese subjects, 25 males and 25 females, with mean age of 34.7 years, extreme of 10 and 59 years. The AI reference values obtained in a sample of the Brazilian population were 0.21< IA < 0.25. There was no significant statistical difference between Brazilians values and Americans ones.