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% 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 seizure control.071

Plasma VEGF Level Changes with Exercise in Patients with Chronic Coronary Artery Disease

The aim of this study was to assess the effect of acute and programmed physical exercise on plasma VEGF levels in chronicstable coronary artery disease patients. Following baseline evaluation, 21 patients <75 years underwent a stress myocardialperfusion scan (acute), and were then randomly assigned to perform programmed rehabilitation exercise or continue withtheir normal therapy. VEGF assessed by SPECT imaging significantly decreased after stress ergometry (from 49.59±6.06 to31.83±5.62 pg/ml; p=0.021). At one month, it increased (70.90±14.44 pg/ml) though not significantly with respect to baselinevalues (p=0.1) and significantly with respect to immediate post-stress values (p<0.01). No significant changes were observedin VEGF at 3 months or when results were compared according to the presence of ischemia or programmed exercise.Acute exercise induced a significant reduction in VEGF values, without differences between programmed exercise and thecontrol group.Con el objetivo de evaluar el efecto del ejercicio físico agudo y programado sobre los niveles plasmáticos de VEGF en pacientescoronarios crónicos estables, se estudiaron 21 pacientes < 75 años a los que luego de la evaluación basal se les realizó unestudio de perfusión miocárdica con esfuerzo (agudo) y posteriormente se asignaron en forma aleatoria a realizar ejerciciosprogramados de rehabilitación o continuar con el tratamiento habitual.Los valores de VEGF disminuyeron significativamente en el posesfuerzo de la ergometría de la SPECT (de 49,59 ± 6,06 a31,83 ± 5,62 pg/ml; p = 0,021). Al mes, los valores aumentaron (70,90 ± 14,44 pg/ml) con tendencia no significativa respectodel valor basal (p = 0,1) y significativamente respecto de los valores del posesfuerzo inmediato (p < 0,01). No se observaroncambios significativos en los valores de VEGF a los 3 meses y tampoco al comparar los resultados según la presencia de isquemiao la realización de ejercicios programados.El ejercicio agudo indujo una reducción significativa en los valores de VEGF, sin diferencias entre el ejercicio programado yel grupo control