MARIA CONCEPCION GARCIA OTADUY
Projetos de Pesquisa
Unidades Organizacionais
Instituto de Radiologia, Hospital das Clínicas, Faculdade de Medicina
LIM/44 - Laboratório de Ressonância Magnética em Neurorradiologia, Hospital das Clínicas, Faculdade de Medicina
LIM/44 - Laboratório de Ressonância Magnética em Neurorradiologia, Hospital das Clínicas, Faculdade de Medicina
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- Diffusion abnormalities of the corpus callosum in patients with malformations of cortical development and epilepsy(2014) ANDRADE, Celi S.; LEITE, Claudia C.; OTADUY, Maria C. G.; LYRA, Katarina P.; VALENTE, Kette D. R.; YASUDA, Clarissa L.; BELTRAMINI, Guilherme C.; BEAULIEU, Christian; GROSS, Donald W.Purpose: Diffusion tensor imaging (DTI) is a magnetic resonance imaging (MRI) technique that can characterize white matter (WM) architecture and microstructure. DTI has demonstrated extensive WM changes in patients with several epileptic syndromes, but few studies have focused on patients with malformations of cortical development (MCD). Our aim was to investigate the quantitative diffusion properties of the corpus callosum (CC), a major commissural bundle critical in inter-hemispheric connectivity, in a large group of patients with MCD. Methods: Thirty-two MCD patients and 32 age and sex-matched control subjects were evaluated with DTI at 3.0 T. We analyzed the three major subdivisions of the CC (genu, body, and splenium) with deterministic tractography to yield fractional anisotropy (FA), mean diffusivity (MD), parallel diffusivity (lambda parallel to) and perpendicular diffusivity (lambda perpendicular to). We further assessed the CC with region of interest (ROI)-based analyses and evaluated different subgroups of MCD (polymicrogyria/schizencephaly, heterotopia, and cortical dysplasia). Partial correlations between diffusion changes and clinical parameters (epilepsy duration and age at disease onset) were also queried. Results: There were significant reductions of FA, accompanied by increases in MD and lambda perpendicular to in all segments of the CC in the patients group with both analytical methods. The absolute differences in FA were greater on ROI-analyses. There were no significant differences between the MCD subgroups, and no correlations between clinical parameters of epilepsy and FA. Conclusions: Our study indicates DTI abnormalities consistent with microstructural changes in the corpus callosum of MCD patients. The findings support the idea that patients with epilepsy secondary to cortical malformations present widespread WM changes that extend beyond the macroscopic MRI-visible lesions.
- MRI investigation of a 6-week trial of lithium in medication-free patients with bipolar depression(2014) ZANETTI, M. V.; OTADUY, M. C. G.; SOUSA, R. T. de; SOEIRO-DE-SOUZA, M. G.; CHAIM, K. T.; GATTAZ, W. F.; BUSATTO, G. F.; LEITE, C. C.; MACHADO-VIEIRA, R.
conferenceObject Prefrontal cortex gamma-aminobutyric acid levels in bipolar I disorder determined using proton magnetic resonance spectroscopy(2014) SOEIRO-DE-SOUZA, M.; OTADUY, M. C. G.; MORENO, R. A.; MORENO, D. H.; VALLADA, H.- Assessment of irradiated brain metastases using dynamic contrast-enhanced magnetic resonance imaging(2014) ALMEIDA-FREITAS, Daniela B.; PINHO, Marco C.; OTADUY, Maria C. G.; BRAGA, Henrique F.; MEIRA-FREITAS, Daniel; LEITE, Claudia da CostaThe purpose of this study was to evaluate the effect of stereotactic radiosurgery (SRS) on cerebral metastases using the transfer constant (K (trans)) assessed by dynamic contrast-enhanced (DCE) MRI. Furthermore, we aimed to evaluate the ability of K (trans) measurements to predict midterm tumor outcomes after SRS. The study received institutional review board approval, and informed consent was obtained from all subjects. Twenty-six adult patients with a total of 34 cerebral metastases underwent T1-weighted DCE MRI in a 1.5-T magnet at baseline (prior to SRS) and 4-8 weeks after treatment. Quantitative analysis of DCE MRI was performed by generating K (trans) parametric maps, and region-of-interest-based measurements were acquired for each metastasis. Conventional MRI was performed at least 16 weeks after SRS to assess midterm tumor outcome using volume variation. The mean (+/- SD) K (trans) value was 0.13 +/- 0.11 min(-1) at baseline and 0.08 +/- 0.07 min(-1) after 4-8 weeks post-treatment (p < 0.001). The mean (+/- SD) total follow-up time was 7.9 +/- 4.7 months. Seventeen patients (22 lesions) underwent midterm MRI. Of those, nine (41 %) lesions had progressed at the midterm follow-up. An increase in K (trans) after SRS was predictive of tumor progression (hazard ratio = 1.50; 95 % CI = 1.16-1.70, p < 0.001). An increase of 15 % in K (trans) showed a sensitivity of 78 % and a specificity of 85 % for the prediction of progression at midterm follow-up. SRS was associated with a reduction of K (trans) values of the cerebral metastases in the early post-treatment period. Furthermore, K (trans) variation as assessed using DCE MRI may be helpful to predict midterm outcomes after SRS.
conferenceObject DIFFUSION TENSOR IMAGING ABNORMALITIES OF THE CORPUS CALLOSUM IN MALFORMATIONS OF CORTICAL DEVELOPMENT(2014) ANDRADE, C. S.; LEITE, C. C.; OTADUY, M. C. G.; LYRA, K. P.; VALENTE, K. D. R.; YASUDA, C. L.; BELTRAMINI, G. C.; BEAULIEU, C.; GROSS, D. W.- Widespread pH abnormalities in patients with malformations of cortical development and epilepsy: A phosphorus-31 brain MR spectroscopy study(2014) ANDRADE, Celi Santos; OTADUY, Maria Concepcion Garcia; VALENTE, Kette Dualibi Ramos; PARK, Eun Joo; KANAS, Alexandre Fligelman; SILVA FILHO, Mauricio Ricardo Moreira da; TSUNEMI, Miriam Harumi; LEITE, Claudia CostaIntroduction: Neuroimaging studies demonstrate that not only the lesions of malformations of cortical development (MCD) but also the normal-appearing parenchyma (NAP) present metabolic impairments, as revealed with H-1-MRS. We have previously detected biochemical disturbances in MCD lesions with phosphorus-31 magnetic resonance spectroscopy (P-31-MRS). Our hypothesis is that pH abnormalities extend beyond the visible lesions. Methods: Three-dimensional P-31-MRS at 3.0 T was performed in 37 patients with epilepsy and MCD, and in 31 matched-control subjects. The patients were assigned into three main MCD subgroups: cortical dysplasia (n = 10); heterotopia (n = 14); schizencephaly/polymicrogyria (n = 13). Voxels (12.5 cm(3)) were selected in five homologous regions containing NAP: right putamen; left putamen; frontoparietal parasagittal cortex; right centrum semiovale; and left centrum semiovale. Robust methods of quantification were applied, and the intracellular pH was calculated with the chemical shifts of inorganic phosphate (Pi) relative to phosphocreatine (PCr). Results: In comparison to controls and considering a Bonferroni adjusted p-value <0.01, MCD patients presented significant reduction in intracellular pH in the frontoparietal parasagittal cortex (6.985 +/- 0.022), right centrum semiovale (7.004 +/- 0.029), and left centrum semiovale (6.995 +/- 0.030), compared to controls (mean values standard deviations of 7.087 +/- 0.048, 7.096 +/- 0.042, 7.088 +/- 0.045, respectively). Dunnet and Dunn tests demonstrated that the differences in pH values remained statistically significant in all MCD subgroups. No significant differences were found for the putamina. Conclusion: The present study demonstrates widespread acidosis in the NAP, and reinforces the idea that MCD visible lesions are only the tip of the iceberg.
- Brain creatine depletion in vegetarians? A cross-sectional H-1-magnetic resonance spectroscopy (H-1-MRS) study(2014) SOLIS, Marina Yazigi; PAINELLI, Vitor de Salles; ARTIOLI, Guilherme Giannini; ROSCHEL, Hamilton; OTADUY, Maria Concepcion; GUALANO, BrunoThe present cross-sectional study aimed to examine the influence of diet on brain creatine (Cr) content by comparing vegetarians with omnivores. Brain Cr content in the posterior cingulate cortex was assessed by proton magnetic resonance spectroscopy (H-1-MRS). Dietary Cr intake was assessed by 3 d food recalls. Vegetarians had lower dietary Cr intake than omnivores (0.03 (SD 0.01) v. 1.34 (SD 0.62) g/d, respectively; P - 0.005). However, vegetarians and omnivores had comparable brain total Cr content (5.999 (SD 0.811) v. 5.917 (SD 0.665) IU, respectively; P = 0.77). In conclusion, dietary Cr did not influence brain Cr content in healthy individuals, suggesting that in normal conditions brain is dependent on its own Cr synthesis.
- Efficacy and safety of creatine supplementation in childhood-onset systemic lupus erythematosus: a randomized, double-blind, placebo-controlled, crossover trial(2014) HAYASHI, A. P.; SOLIS, M. Y.; SAPIENZA, M. T.; OTADUY, M. C. G.; PINTO, A. L. de Sa; SILVA, C. A.; SALLUM, A. M. E.; PEREIRA, R. M. R.; GUALANO, B.Introduction: Creatine supplementation has emerged as a promising non-pharmacological therapeutic strategy to counteract muscle dysfunction and low lean mass in a variety of conditions, including in pediatric and rheumatic diseases. The objective of this study was to examine the efficacy and safety of creatine supplementation in childhood systemic lupus erythematosus (C-SLE). Methods: C-SLE patients with mild disease activity (n = 15) received placebo or creatine supplementation in a randomized fashion using a crossover, double-blind, repeated-measures design. The participants were assessed at baseline and after 12 weeks in each arm, interspersed by an eight-week washout period. The primary outcomes were muscle function, as assessed by a battery of tests including one-maximum repetition (1-RM) tests, the timed-up-and-go test, the timed-stands test, and the handgrip test. Secondary outcomes included body composition, biochemical markers of bone remodeling, aerobic conditioning, quality of life, and physical capacity. Possible differences in dietary intake were assessed by three 24-hour dietary recalls. Muscle phosphorylcreatine content was measured through phosphorus magnetic resonance spectroscopy (31 P-MRS). The safety of the intervention was assessed by laboratory parameters, and kidney function was measured by 51 Cr-EDTA clearance. Additionally, self-reported adverse events were recorded throughout the trial. Results: Intramuscular phosphorylcreatine content was not significantly different between creatine and placebo before or after the intervention (creatine-Pre: 20.5 +/- 2.6, Post: 20.4 +/- 4.1, placebo-Pre: 19.8 +/- 2.0; Post: 20.2 +/- 3.2 mmol/kg wet muscle; p = 0.70 for interaction between conditions). In addition, probably as a consequence of the lack of change in intramuscular phosphorylcreatine content, there were no significant changes between placebo and creatine for any muscle function and aerobic conditioning parameters, lean mass, fat mass, bone mass, and quality of life scores (p > 0.05). The 51 Cr-EDTA clearance was not altered by creatine supplementation and no side effects were noticed. Conclusion: A 12-week creatine supplementation protocol at 0.1 g/kg/d is well tolerated and free of adverse effects but did not affect intramuscular phosphorylcreatine, muscle function, free-fat mass or quality of life in non-active C-SLE patients.