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1.
Radiol Res Pract ; 2012: 727810, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22848821

RESUMO

Introduction. Aggressive surgical resection constitutes the optimal treatment for intracranial gliomas. However, the proximity of a tumor to eloquent areas requires exact knowledge of its anatomic relationships to functional cortex. The purpose of our study was to evaluate fMRI's accuracy by comparing it to intraoperative cortical stimulation (DCS) mapping. Material and Methods. Eighty-seven patients, with presumed glioma diagnosis, underwent preoperative fMRI and intraoperative DCS for cortical mapping during tumor resection. Findings of fMRI and DCS were considered concordant if the identified cortical centers were less than 5 mm apart. Pre and postoperative Karnofsky Performance Scale and Spitzer scores were recorded. A postoperative MRI was obtained for assessing the extent of resection. Results. The areas of interest were identified by fMRI and DCS in all participants. The concordance between fMRI and DCS was 91.9% regarding sensory-motor cortex, 100% for visual cortex, and 85.4% for language. Data analysis showed that patients with better functional condition demonstrated higher concordance rates, while there also was a weak association between tumor grade and concordance rate. The mean extent of tumor resection was 96.7%. Conclusions. Functional MRI is a highly accurate preoperative methodology for sensory-motor mapping. However, in language mapping, DCS remains necessary for accurate localization.

2.
Neurosurg Focus ; 32(3): E3, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22380857

RESUMO

OBJECT: The purpose of this prospective study was to compare the results of proton MR spectroscopy (MRS) in temporal poles in patients with unilateral mesial temporal sclerosis (MTS) with the histopathological findings of the resected temporal poles. METHODS: A total of 23 patients (14 male and 9 female) with a mean age of 25.2 years (range 17-45 years) were included in this study, which was conducted over a 4-year period. All patients suffered medically refractory epilepsy due to unilateral, MRI-proven MTS, with no other imaging abnormalities. All participants underwent preoperative single-voxel proton MRS using a 3-T MRI unit. The hippocampi and temporal poles were examined bilaterally. The concentrations of N-acetyl-aspartate (NAA), choline (Cho), and creatine (Cr) were measured, and the NAA/Cho, NAA/Cr, and NAA/Cho+Cr ratios were calculated. All patients underwent anterior temporal lobectomy and ipsilateral amygdalohippocampectomy, and surgical specimens from the temporal poles were sent for histopathological examination. Comparisons of the spectroscopic and histopathological results of the resected temporal poles were performed. The modified Engel classification system was used for evaluating seizure outcome in the cohort. RESULTS: The preoperative spectroscopic profiles of the sclerotic hippocampi were abnormal in all patients, and the contralateral hippocampus showed altered spectroscopic findings in 12 patients (52.2%). Spectroscopy of the temporal poles demonstrated severely decreased concentrations of NAA, markedly increased concentrations of Cho, and increased concentrations of Cr in the temporal pole ipsilateral to the MTS in 15 patients (65.2%). Similarly, the NAA/Cho, NAA/Cr, and NAA/Cho+Cr ratios were severely decreased in the temporal pole ipsilateral to the MTS in 16 patients (69.6%). Histopathological examination of the resected temporal poles demonstrated ischemic changes in 5 patients (21.7%), gliotic changes in 4 (17.4%), demyelinating changes in 3 (13.0%), and microdysplastic changes in 1 patient (4.3%). Comparisons of the spectroscopic and histopathological findings showed that the sensitivity of proton MRS was 100%, its specificity was 80%, its positive predictive value was 87%, and its negative predictive value was 100%. The mean follow-up time in this study was 3.4 years. At the end of the 2nd postoperative year, 17 patients (73.9%) were in Engel Class I, 5 (21.7%) were in Class II, and 1 (4.3%) was in Class III. CONCLUSIONS: Proton MRS detected altered ipsilateral temporal pole metabolism in patients with unilateral MTS. These metabolic changes were associated with permanent histological abnormalities of the temporal pole. This finding demonstrates that MTS may be a more diffuse histological process, and exact preoperative knowledge of its temporal extent becomes of paramount importance in the selection of the best surgical approach in these patients. Further validation of the observations is necessary for defining the role of temporal pole proton MRS in cases of temporal lobe epilepsy.


Assuntos
Epilepsia do Lobo Temporal/diagnóstico , Epilepsia do Lobo Temporal/cirurgia , Espectroscopia de Ressonância Magnética , Cuidados Pré-Operatórios , Prótons , Adolescente , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Colina/metabolismo , Creatina/metabolismo , Feminino , Lateralidade Funcional , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neurocirurgia/métodos , Estudos Retrospectivos , Adulto Jovem
3.
J Cardiovasc Magn Reson ; 13: 34, 2011 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-21733147

RESUMO

BACKGROUND: Thalassaemia major (TM) patients need regular blood transfusions that lead to accumulation of iron and death from heart failure. Deferiprone has been reported to be superior to deferoxamine for the removal of cardiac iron and improvement in left ventricular (LV) function but little is known of their relative effects on the right ventricle (RV), which is being increasingly recognised as an important prognostic factor in cardiomyopathy. Therefore data from a prospective randomised controlled trial (RCT) comparing these chelators was retrospectively analysed to assess the RV responses to these drugs. METHODS: In the RCT, 61 TM patients were randomised to receive either deferiprone or deferoxamine monotherapy, and CMR scans for T2* and cardiac function were obtained. Data were re-analysed for RV volumes and function at baseline, and after 6 and 12 months of treatment. RESULTS: From baseline to 12 months, deferiprone reduced RV end systolic volume (ESV) from 37.7 to 34.2 mL (p=0.008), whilst RV ejection fraction (EF) increased from 69.6 to 72.2% (p=0.001). This was associated with a 27% increase in T2* (p<0.001) and 3.1% increase in LVEF (p<0.001). By contrast, deferoxamine showed no change in RVESV (38.1 to 39.1 mL, p=0.38), or RVEF (70.0 to 69.9%, p=0.93) whereas the T2* increased by 13% (p<0.001), but with no change in LVEF (0.32%; p=0.66). Analysis of between drugs treatment effects, showed significant improvements favouring deferiprone with a mean effect on RVESV of -1.82 mL (p=0.014) and 1.16% for RVEF (p=0.009). Using regression analysis the improvement in RVEF at 12 months was shown to be greater in patients with lower baseline EF values (p<0.001), with a significant difference in RVEF of 3.5% favouring deferiprone over deferoxamine (p=0.012). CONCLUSION: In this retrospective analysis of a prospective RCT, deferiprone monotherapy was superior to deferoxamine for improvement in RVEF and end-systolic volume. This improvement in the RV volumes and function may contribute to the improved cardiac outcomes seen with deferiprone.


Assuntos
Cardiomiopatias/tratamento farmacológico , Desferroxamina/uso terapêutico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Miocárdio/metabolismo , Piridonas/uso terapêutico , Sideróforos/uso terapêutico , Reação Transfusional , Função Ventricular Direita/efeitos dos fármacos , Talassemia beta/terapia , Adulto , Análise de Variância , Cardiomiopatias/diagnóstico , Cardiomiopatias/etiologia , Cardiomiopatias/metabolismo , Cardiomiopatias/fisiopatologia , Deferiprona , Feminino , Grécia , Humanos , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/fisiopatologia , Itália , Imageamento por Ressonância Magnética , Masculino , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Volume Sistólico/efeitos dos fármacos , Fatores de Tempo , Resultado do Tratamento , Função Ventricular Esquerda/efeitos dos fármacos , Adulto Jovem , Talassemia beta/sangue
4.
Br J Haematol ; 151(5): 504-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20950401

RESUMO

Abnormal iron regulation in patients with thalassaemia intermedia may lead to iron overload even in the absence of transfusions. There are limited data on iron chelator use in patients with thalassaemia intermedia and no guidelines exist for the management of iron overload. We present data from 11 patients with thalassaemia intermedia treated with deferasirox (Exjade(®) , 10-20 mg/kg/d) for 24 months. Liver iron concentration and serum ferritin levels significantly decreased over the first 12 months (P = 0·005) and continued to decrease over the remainder of the study (P = 0·005). This small-scale study indicated that deferasirox may be suitable for controlling iron levels in patients with thalassaemia intermedia.


Assuntos
Benzoatos/uso terapêutico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Triazóis/uso terapêutico , Talassemia beta/complicações , Adulto , Benzoatos/efeitos adversos , Deferasirox , Feminino , Ferritinas/sangue , Humanos , Ferro/metabolismo , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/metabolismo , Fígado/metabolismo , Imageamento por Ressonância Magnética , Masculino , Resultado do Tratamento , Triazóis/efeitos adversos , Adulto Jovem , Talassemia beta/metabolismo
5.
Br J Haematol ; 151(4): 397-401, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20813008

RESUMO

Cardiac Magnetic Resonance (CMR) has replaced all other surrogate measurements in the determination of transfusional cardiac iron overload in patients with thalassaemia major. We aimed to determine the diagnostic value of CMR T2* with respect to cardiac dysfunction (CD) as determined by CMR-derived left ventricular ejection fraction (LVEF). Cardiac T2* values and LVEF measured by CMR were recorded in 303 patients with thalassaemia major, at the time of their first CMR. T2* was correlated with LVEF (regression coefficient: 0·57, P<0·001). The prevalence of CD was 32·9% in patients with T2*≤8 ms, 12·5% in patients with T2*>8 ms and ≤14 ms and reduced to 9·1% in patients with T2* between 14-20 ms. As the probability of CD is progressively, and not suddenly, reduced with increasing values of T2*, CMR has a limited diagnostic value for CD (Receiver operating characteristic analysis, area under the curve = 0·68). Patients with cardiac T2*≤8 ms require careful and intensive management. This risk decreases with increasing values of T2* but even in mildly loaded patients the probability of impaired LVEF is not negligible.


Assuntos
Sobrecarga de Ferro/diagnóstico , Volume Sistólico/fisiologia , Reação Transfusional , Disfunção Ventricular Esquerda/diagnóstico , Talassemia beta/terapia , Adulto , Métodos Epidemiológicos , Feminino , Humanos , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Masculino , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologia , Adulto Jovem , Talassemia beta/fisiopatologia
6.
Int J Cardiovasc Imaging ; 25(8): 777-83, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19680779

RESUMO

In b-thalassemia, myocardial iron overload contributes to heart failure, despite chelation treatment. We hypothesized that myocardial T2*, an index of iron overload, influences patients' physical activity. We assessed a thalassemic population by both cardiovascular magnetic resonance imaging (CMR) and ergospirometry test. Sixty-six thalassemic patients aged 27 (19-40) years, 30 without (NHF) and 36 with heart failure (HF), were studied. Cardiac T2* and left ventricular ejection fraction (LVEF) were evaluated using a 1.5 T system. VO(2max), AT, Mets and duration of exercise by ergospirometry were also assessed. Myocardial T2* was lower in HF compared to NHF patients (14.7 +/- 6.6 vs. 39 +/- 2 ms, P < 0.001). LVEDV and LVESV were higher in HF group compared to NHF patients (139.9 +/- 16.3 vs. 124.6 +/- 20.86 ml, P < 0.01 and 94.9 +/- 24 vs. 38.3 +/- 10.1 ml, P < 0.001, respectively). Additionally, LVEF in HF was lower compared to NHF patients (21.3 +/- 6.1% vs. 69.6 +/- 3.7, P < 0.001, respectively). All exercise parameters were lower in HF compared to NHF patients (P < 0.001). Patients within the HF group were additionally analyzed according to T2* values (<10 ms). HF patients with T2* < 10 ms (n = 13) were considered as high iron overloaded (HF-H) and the rest of them (n = 23) as (HF-L). Although LVEDV, LVESV, LVEF were similar in the two subgroups, the exercise parameters were significantly lower in the HF-H group (P < 0.001). Heart T2* correlated with all exercise parameters (P < 0.001). HF thalassemic patients have reduced exercise indexes compared to non HF. Myocardial iron overload, expressed as T2*, has a direct influence on exercise capacity, independent of LV ejection fraction and functional class.


Assuntos
Tolerância ao Exercício , Insuficiência Cardíaca/diagnóstico , Sobrecarga de Ferro/diagnóstico , Ferro/metabolismo , Imageamento por Ressonância Magnética , Miocárdio/metabolismo , Talassemia beta/diagnóstico , Adulto , Teste de Esforço , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/patologia , Sobrecarga de Ferro/fisiopatologia , Miocárdio/patologia , Valor Preditivo dos Testes , Espirometria , Volume Sistólico , Função Ventricular Esquerda , Adulto Jovem , Talassemia beta/metabolismo , Talassemia beta/patologia , Talassemia beta/fisiopatologia
7.
Neurosurg Focus ; 24(6): E7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18518752

RESUMO

Despite recent advances in neuroimaging, differentiation between cerebral abscesses and necrotic tumors with ring-type contrast enhancement can be puzzling at times. The introduction of advanced imaging techniques, such as diffusion-weighted imaging, has contributed to the identification of cerebral abscesses. However, differentiation may be impossible with imaging only. In this review the authors evaluate the role of proton magnetic resonance (MR) spectroscopy in differentiating between cerebral abscesses and necrotic tumors and address the spectral characteristics of intracranial abscesses. A large number of metabolites not detected in the normal brain spectra may be detected and give valuable information regarding the nature of the abscesses. Proton MR spectroscopy is a safe, noninvasive diagnostic modality, which could significantly increase the accuracy and specificity of conventional MR imaging in differentiating between malignant tumors and cerebral abscesses and provide valuable information regarding the cause of an abscess, as well as, its response to the chosen treatment.


Assuntos
Abscesso Encefálico/classificação , Abscesso Encefálico/diagnóstico , Espectroscopia de Ressonância Magnética/métodos , Humanos , Espectroscopia de Ressonância Magnética/normas , Prótons
8.
Int J Cardiovasc Imaging ; 24(8): 849-54, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18581254

RESUMO

INTRODUCTION: b-Thalassemia major (TM) and thalassemia intermedia (TI) are forms of inherited hemoglobinopathies. Our aim was to evaluate a population of asymptomatic TM and TI patients using cardiovascular magnetic resonance (CMR). We hypothesized that the TI group could be differentiated from the TM group based on T2*. We also hypothesized that the TI group would demonstrate significantly higher cardiac output compared to the TM group. PATIENTS AND METHODS: Twenty-one consecutive TI patients aged 23(19-25) years, 21 TM patients and 21 age and sex matched controls were studied. Evaluation of heart, liver T2* relaxation time and right and left ventricular parameters was performed using a 1.5 T system. RESULTS: Myocardial and liver T2* values were significantly higher in TI patients compared to TM (34.35 +/- 2.36 vs 15.77 +/- 3.53 m, P < 0.001 and 5.12 +/- 6.52 vs 1.36 +/- 0.53 ms, P < 0.001, respectively). Controls had myocardial T2* 35.07 +/- 4.52 ms (similar to TI patients, but significantly increased compared to TM patients, P < 0.001) and liver T2* 26.28 +/- 2.37 ms (significantly increased compared to both TI and TM patients, P < 0.001). Left ventricular end-diastolic (LVEDV), end-systolic (LVESV) volumes and left ventricular ejection fraction (LVEF) were higher in TI patients compared to TM (P < 0.001). Stroke volume (LVSV), cardiac output (LVCO) and cardiac index (LVCI) were similarly increased in TI patients compared to TM (P < 0.001). Right ventricular end-diastolic volume (RVEDV), right ventricular end-systolic volume (RVESV) and right ventricular ejection fraction (RVEF) were higher in TI patients compared to TM (P < 0.001). CONCLUSIONS: Although in TM iron plays a crucial role in the evolution of the disease, in TI the high output cardiac state seems to be the most prominent finding.


Assuntos
Sobrecarga de Ferro/patologia , Fígado/metabolismo , Imageamento por Ressonância Magnética/métodos , Miocárdio/metabolismo , Talassemia beta/patologia , Adulto , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Sobrecarga de Ferro/fisiopatologia , Masculino , Variações Dependentes do Observador , Imagens de Fantasmas , Volume Sistólico , Talassemia beta/fisiopatologia
9.
Eur J Haematol ; 81(2): 157-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18462251

RESUMO

In general, in women with transfusion-dependent thalassemia, during pregnancy, iron chelation therapy is ceased. We report a splenectomized patient, who was an excellent complier with chelation therapy, who before embarking on a pregnancy showed no evidence of iron overload, with normal cardiac, thyroid function and glucose metabolism. Laboratory findings showed ferritin 67 microg/L, myocardial T(2)* of 34 ms and liver magnetic resonance imaging (MRI) liver iron concentration of 1 mg/g dry weight. She became pregnant by in vitro fertilization in October 2006, delivery occurred in June 2007. She breast fed for 2 months. After 12 months without iron chelation, ferritin was 1583 microg/L. Quantitative MRI showed myocardial T(2)* of 27 ms, that the liver iron concentration had increased to 11.3 mg/g dry weight, indicative of moderate to heavy iron load. This case demonstrates that iron overload can develop rapidly and that physicians caring for patients with transfusion-dependent thalassemia should be particularly alert to any discontinuation of chelation therapy over time.


Assuntos
Terapia por Quelação , Sobrecarga de Ferro/etiologia , Talassemia/complicações , Suspensão de Tratamento , Adulto , Transfusão de Sangue , Feminino , Ferritinas/sangue , Humanos , Ferro/metabolismo , Quelantes de Ferro/uso terapêutico , Fígado/metabolismo , Gravidez , Talassemia/terapia
10.
Hemoglobin ; 32(1-2): 75-83, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18274985

RESUMO

Early attempts to use magnetic resonance imaging (MRI) for assessing iron overload in beta-thalassemia (thal) patients began more than 20 years ago. With advances in MRI, more quantitative efforts focused on measuring transverse relaxation time rates (R2 and R2*) of the liver and/or myocardium. Recently, calibration curves of R2 and R2* were reported that allowed one to determine the absolute concentrations of iron in the liver, provided that R2 and R2* were determined with the same technique. The difficulty of obtaining sufficient myocardium biopsy samples has prevented similar calibration curves being reported for the myocardium. Preliminary data indicate that liver and myocardium R2* vs. R2 plots are similar over a large range of R2* and R2 values. Obviously, myocardium biopsy samples are needed to confirm whether myocardium R2* and R2 plots vs. iron concentration are similar to those published for the liver. The various methods for determining R2 and R2* are discussed. It is suggested to use both R2* and R2 for assessing iron overload in the liver and myocardium.


Assuntos
Sobrecarga de Ferro/diagnóstico , Imageamento por Ressonância Magnética/métodos , Talassemia beta/diagnóstico , Adolescente , Adulto , Terapia por Quelação , Criança , Feminino , Ferritinas/sangue , Humanos , Quelantes de Ferro/uso terapêutico , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Sensibilidade e Especificidade , Talassemia beta/metabolismo
11.
Cardiovasc Ultrasound ; 5: 24, 2007 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-17629926

RESUMO

BACKGROUND: Despite advances in survival in patients with thalassemia major (TM) the most common cause of death is cardiac disease. Regular cardiac follow-up is imperative in order to identify and reverse pathology. Cardiac Magnetic Resonance (CMR) and Echocardiography (US) are applied in parallel to TM patients for cardiac evaluation and ongoing monitoring. A comparison between mutual features would be useful in order to assess the accuracy and reliability of the two methods, with a particular focus on routine US application. TM's special attributes offer an excellent opportunity for cardiac imaging research that has universal general purpose applications. METHODS: 135 TM patients underwent US (Teichholz's M-mode formula - rapidly accessible means of measuring volumes and ejection fraction) and CMR volumetry. Paired-samples t-test, Passing & Badlock regression and Bland & Altman plot were used while comparing the common parameters between the CMR and the US. RESULTS: We found that the US volumes were underestimated, especially the end-diastolic volume (p < 0.001). The end-systolic volume showed a borderline two-tailed probability (p approximately 0.05). The correlation for the ejection fraction was acceptable (r = 0.60) without a statistically significant difference (p = 0.37) and the Bland Altman plot range was narrow (25.8%). There was a satisfactory correlation of the US' shortening fraction with CMR's ejection fraction (r = 0.58). CONCLUSION: In cases where cardiac wall movement abnormalities are absent, the US Teichholz's M-mode formula for volume measurements, though less sophisticated in comparison to the high resolution CMR technique, offers an adequate ejection fraction estimation for routine use, especially when monitoring gross alterations in cardiac function over time, and is easy to perform.


Assuntos
Transfusão de Sangue , Ecocardiografia Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/prevenção & controle , Talassemia beta/diagnóstico , Talassemia beta/terapia , Adulto , Feminino , Humanos , Masculino , Prognóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento , Disfunção Ventricular Esquerda/etiologia , Talassemia beta/complicações
12.
Haematologica ; 92(1): 131-2, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17229649

RESUMO

Recent advances in magnetic resonance imaging (MRI) techniques allow the assessment of iron overload in tissues 1 especially the heart, 2 in transfusion-dependent thalassemia patients. The R2* value (1/T2*) recorded in the intraventricular septum of the heart indirectly measures the degree of cardiac iron load. Applying this new technology we looked at a number of historical and biochemical parameters in order to determine their relationship to cardiac iron overload and the effect of cardiac iron on functional and structural changes of the heart in transfusion-dependent thalassemics.


Assuntos
Imageamento por Ressonância Magnética/métodos , Miocárdio/metabolismo , Talassemia/diagnóstico , Talassemia/patologia , Transfusão de Sangue , Quelantes/farmacologia , Humanos , Ferro/metabolismo , Sobrecarga de Ferro/terapia , Fígado/metabolismo , Valor Preditivo dos Testes , Software , Fatores de Tempo
13.
Int J Cardiovasc Imaging ; 23(6): 739-45, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17235481

RESUMO

Bone marrow transplantation (BMT) is the only complete cure for b-thalassemia. Iron depletion therapy is still required to remove excess iron, accumulated before BMT. Hepatic and myocardial iron load were evaluated using T2* magnetic resonance in 8 ex-thalassemic patients after BMT, aged 19.5 +/- 4.25 years, who were in iron depletion therapy. Average hepatic T2* was 18.8 +/- 11.0 msec (4.1-35.0 msec). In 4 out of 8 patients iron overload was detected, not exceeding however 4 mg/gr dry tissue. Average heart T2* was 31.0 +/- 4.6 msec (25.6-35.2 msec), not significantly different (P = 0.18) from our age-matched normal population (33.0 +/- 4.0). Normal left ventricular ejection fraction was found in 7 out of 8 patients (mean 64.5 +/- 7.0%) with the remaining having a marginal value of 54.1%. Ferritin level before BMT was 1748 +/- 451 mug/l and dropped to 536 +/- 260 microg/l at the end of iron depletion therapy after BMT. Current ferritin level was 271 +/- 253 microg/l and although it was significant lower compared to both ferritin before BMT (P < 0.001) and after iron depletion (P < 0.001), evidence of residual hepatic iron load was identified by T2*. Hepatic and myocardial T2* magnetic resonance can be used as a more reliable index than ferritin for evaluation of iron depletion therapy in ex-thalassemic patients after BMT.


Assuntos
Transplante de Medula Óssea , Sobrecarga de Ferro/diagnóstico , Fígado/química , Imageamento por Ressonância Magnética/métodos , Miocárdio/química , Talassemia beta/patologia , Talassemia beta/terapia , Adolescente , Adulto , Criança , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Reprodutibilidade dos Testes , Estatísticas não Paramétricas
14.
Eur J Haematol ; 78(1): 58-65, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17038018

RESUMO

BACKGROUND AND OBJECTIVE: Heart iron load (cardiac Fe) can be indirectly quantified by cardiac magnetic resonance (CMR) T2*. CMR accessibility is limited, whereas echocardiography (Echo) is relatively inexpensive and readily available. The objective was to find Echo parameters that may be useful for predicting cardiac Fe. DESIGN AND METHODS: We compared a number of parameters derived from Echo to cardiac Fe in 142 thalassaemia major patients who had undergone a CMR study. RESULTS: All patients with decreased left ventricular (LV) function had cardiac Fe. After removing those patients from the analysis, the total diameter index (Tdi) >5.57 cms/m2, left atrial diameter index >2.41 cm/m2, and the diastolic parameter E/A > 1.96 were highly specific (91.4%, 97.1% and 96.9% respectively) but had low sensitivity (31.8%, 20.45% and 21.8%) in predicting iron load. A right ventricular index >1.47 cm/m2, LV systolic index >2.26 cm/m2 or Tdi >6.26 cm/m2 discriminated between patients with no, or mild to moderate cardiac Fe from those with heavy load, with specificity of 91%, 98.5%, and 98.5%, respectively, but with low sensitivity. INTERPRETATION AND CONCLUSIONS: Echo parameters for cardiac Fe prediction have restricted value, whereas CMR is essential to assess cardiac Fe. However, patients with decreased LV systolic function should be considered a priori as having cardiac Fe, and chelation therapy should be intensified. This also applies to patients who have the above-described Echo criterion values, even if CMR is not available. Once a patient is found by CMR to have cardiac Fe, then the above Echo criterion values may be useful for ongoing monitoring.


Assuntos
Terapia por Quelação , Ecocardiografia , Quelantes de Ferro/uso terapêutico , Imageamento por Ressonância Magnética , Talassemia beta/diagnóstico , Adulto , Feminino , Humanos , Ferro/metabolismo , Masculino , Sensibilidade e Especificidade , Resultado do Tratamento , Disfunção Ventricular Esquerda/patologia , Talassemia beta/terapia
16.
Br J Haematol ; 134(4): 438-44, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16822284

RESUMO

Recently introduced chelation regimens that combine deferoxamine (DFO) and deferiprone have been shown to have greater efficacy in promoting iron excretion than either chelator alone and have been associated with rapid reduction of the iron load in the heart and liver, and with reversal of cardiac dysfunction. It is unclear whether this combined therapy could be associated with a reduction in iron load or decline in the severity of iron-induced endocrinopathies. Starting in January 2001, 42 patients with beta-thalassaemia major, previously maintained on subcutaneous DFO only, were switched to combined treatment with DFO and deferiprone. The primary endpoint was to investigate the effects of this therapy on the glucose metabolism characteristics of this population. Combination therapy markedly decreased ferritin levels (638 +/- 1345 vs. 2991 +/- 2093 microg/l, P < 0.001). Glucose responses were improved at all times during an oral glucose tolerance test, particularly in patients in early stages of glucose intolerance. Glucose quantitative secretion also decreased significantly with combined therapy, while no significant change occurred in insulin levels in any group. Insulin secretion, according to the homeostasis assessment model, markedly increased in all groups, while overall reduction in insulin sensitivity did not reach statistical significance. This study showed that the combination of DFO and deferiprone was associated with an improvement in liver iron deposition and glucose intolerance.


Assuntos
Glicemia/metabolismo , Desferroxamina/uso terapêutico , Quelantes de Ferro/uso terapêutico , Piridonas/uso terapêutico , Talassemia beta/sangue , Talassemia beta/terapia , Adolescente , Adulto , Análise de Variância , Terapia por Quelação , Criança , Deferiprona , Quimioterapia Combinada , Feminino , Humanos , Insulina/sangue , Sobrecarga de Ferro/tratamento farmacológico , Masculino , Resultado do Tratamento
17.
Blood ; 107(9): 3738-44, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16352815

RESUMO

Most deaths in beta-thalassemia major result from cardiac complications due to iron overload. Differential effects on myocardial siderosis may exist between different chelators. A randomized controlled trial was performed in 61 patients previously maintained on subcutaneous deferoxamine. The primary end point was the change in myocardial siderosis (myocardial T2(*)) over 1 year in patients maintained on subcutaneous deferoxamine or those switched to oral deferiprone monotherapy. The dose of deferiprone was 92 mg/kg/d and deferoxamine was 43 mg/kg for 5.7 d/wk. Compliance was 94% +/- 5.3% and 93% +/- 9.7% (P = .81), respectively. The improvement in myocardial T2(*) was significantly greater for deferiprone than deferoxamine (27% vs 13%; P = .023). Left ventricular ejection fraction increased significantly more in the deferiprone-treated group (3.1% vs 0.3% absolute units; P = .003). The changes in liver iron level (-0.93 mg/g dry weight vs -1.54 mg/g dry weight; P = .40) and serum ferritin level (-181 microg/L vs -466 microg/L; P = .16), respectively, were not significantly different between groups. The most frequent adverse events were transient gastrointestinal symptoms for deferiprone-treated patients and local reactions at the infusion site for deferoxamine. There were no episodes of agranulocytosis. Deferiprone monotherapy was significantly more effective than deferoxamine over 1 year in improving asymptomatic myocardial siderosis in beta-thalassemia major.


Assuntos
Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/etiologia , Desferroxamina/uso terapêutico , Quelantes de Ferro/uso terapêutico , Piridonas/uso terapêutico , Siderose/tratamento farmacológico , Siderose/etiologia , Talassemia beta/complicações , Talassemia beta/tratamento farmacológico , Adulto , Cardiomiopatias/metabolismo , Deferiprona , Desferroxamina/efeitos adversos , Feminino , Humanos , Ferro/metabolismo , Quelantes de Ferro/efeitos adversos , Masculino , Piridonas/efeitos adversos , Siderose/metabolismo , Talassemia beta/metabolismo
18.
Stereotact Funct Neurosurg ; 82(2-3): 90-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15305081

RESUMO

BACKGROUND: Proton magnetic resonance spectroscopy (1H MRS) constitutes a promising modality to assess intracranial pathology. We present our experience using this method in grading solid brain astrocytomas. MATERIAL AND METHODS: Using a 1.5-Tesla MRI unit, 71 patients with the radiographic diagnosis of astrocytoma were examined. Water-suppressed single-voxel 1H MRS was employed in all of our patients. The concentrations of choline (Cho), N-acetyl-aspartate (NAA), phosphocreatine-creatine (Pcr-Cr), myo-inositol (MI), lactate (Lac), lipids (Lip) as well as the metabolite ratios of Cho/Pcr-Cr, NAA/PCr-Cr and NAA/Cho were calculated. An appropriate surgical biopsy was performed. Standard pathology examination was employed in a double-blinded fashion. RESULTS: An increased concentration of Cho and decreased concentrations of Pcr-Cr and NAA were detected. The concentrations of Lac, Lip and MI varied inconsistently, even among tumors of the same histologic grade. The Cho/Pcr-Cr ratio was calculated. This ratio was found to be 2.15 +/- 0.26 in 27 patients with astrocytomas grade I and II, 2.78 +/- 0.09 in 18 patients with grade III, and 5.40 +/- 0.16 in 26 patients with grade IV. DISCUSSION: The increased concentration of Cho is due to the increased cellularity and a relatively increased number of membranous structures in highly malignant tumors. In abnormal anaerobic metabolic tumor states there is relatively less phosphorylization of creatine. By using the Cho/Pcr-Cr ratio the concomitant effects of structural and metabolic alteration can thereby be emphasized for diagnostic advantage. CONCLUSION: The Cho/Pcr-Cr is a very important and statistically significant marker (p = 0.043) determining the degree of intracranial astrocytoma malignancy.


Assuntos
Astrocitoma/diagnóstico , Neoplasias Encefálicas/diagnóstico , Espectroscopia de Ressonância Magnética/métodos , Adulto , Idoso , Análise de Variância , Astrocitoma/classificação , Astrocitoma/metabolismo , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/metabolismo , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prótons
19.
Pediatr Endocrinol Rev ; 2 Suppl 2: 279-81, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16462711

RESUMO

Thalassaemic patients with haemocromatosis often present with metabolic disturbances such as diabetes mellitus. A group of adult thalassaemic patients who received intensive oral and subcutaneous chelation therapy (Defferiprone/Ferriprox and Desferioxamine/Desferal) for a period of 24-36 months was studied for the presence of glucose metabolism disturbances (GMD). Investigation of the prevalence of diabetes mellitus (DM) and impaired glucose tolerance (IGT) was carried out by yearly oral glucose tolerance tests (OGTT). Results showed that GMD (DM and IGT) improved in 1/3 of the patients after the intensive combined chelation treatment, a finding that we attributed to a reduction in liver iron deposits. Although this study is still in progress we believe that intensive combined chelation therapy may have a positive effect on glucose metabolism.


Assuntos
Terapia por Quelação/métodos , Desferroxamina/uso terapêutico , Diabetes Mellitus/tratamento farmacológico , Intolerância à Glucose/tratamento farmacológico , Quelantes de Ferro/uso terapêutico , Piridonas/uso terapêutico , Talassemia beta/tratamento farmacológico , Adulto , Deferiprona , Diabetes Mellitus/sangue , Diabetes Mellitus/metabolismo , Quimioterapia Combinada , Feminino , Ferritinas/sangue , Intolerância à Glucose/sangue , Intolerância à Glucose/metabolismo , Teste de Tolerância a Glucose , Humanos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/metabolismo , Fígado/metabolismo , Masculino , Talassemia beta/sangue , Talassemia beta/metabolismo , Talassemia beta/terapia
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