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1.
Eur J Nucl Med Mol Imaging ; 47(5): 1252-1260, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31915897

RESUMO

PURPOSE: The aim of our study was to comprehensively evaluate the most valuable metabolic parameters of cervical tumours and pelvic lymph nodes (PLN) by FDG-PET/CT to predict para-aortic lymph node (PALN) metastasis and stratify patients for surgical staging. METHODS: The study included patients with locally advanced cervical cancer, negative PALN uptake on preoperative FDG-PET/CT, and para-aortic lymphadenectomy. Two senior nuclear medicine physicians expert in gynaecologic oncology reviewed all PET/CT exams, and extracted tumour SUVmax, MTV, and TLG, as well as PLN. Prognostic parameters of PALN involvement were identified using ROC curves and logistic regression analysis. RESULTS: One hundred and twenty-five consecutive locally advanced cervical cancer patients were included. The FDG-PET/CT false-negative rate was, respectively, 27.7% (13/47) and 5.1% (4/78) in patients with and without FDG-PET/CT PLN uptake. The AUC of cervical tumour size, SUVmax, MTV, and TLG was, respectively, 0.75 (0.62-0.87), 0.59 (0.44-0.76), 0.75 (0.60-0.90), and 0.71 (0.56-0.86). The AUC of PLN size, SUVmax, SUVmean, PLN SUVmax/Tumour SUVmax ratio, MTV, and TLG was, respectively, 0.57 (0.37-0.78), 0.82 (0.68-0.95), 0.77 (0.61-0.94), 0.85 (0.72-0.98), 0.69 (0.51-0.87), and 0.74 (0.57-0.91). The metabolic parameter showing the best trade-off between sensitivity and specificity to predict PALN involvement was the ratio between PLN and tumour SUVmax. CONCLUSION: The risk of PALN metastasis in FDG-PET/CT negative PLN patients is very low, so para-aortic lymphadenectomy does not seem justified. In patients with preoperative PLN uptake on FDG-PET/CT, surgical staging led to treatment modification in more than 25% of cases and should therefore be performed. Patients with more than one positive PLN and high PLN metabolic activity are at high risk of para-aortic extension and recurrence. Further prospective evaluation is required to consider intensified treatment modalities without prior PALN dissection.


Assuntos
Neoplasias do Colo do Útero , Feminino , Fluordesoxiglucose F18 , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Linfonodos/cirurgia , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/cirurgia
2.
J Craniomaxillofac Surg ; 46(5): 743-748, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29567343

RESUMO

PURPOSE: To study an original 3D visualization of head and neck squamous cell carcinoma extending to the mandible by using [18F]-NaF PET/CT and [18F]-FDG PET/CT imaging along with a new innovative FDG and NaF image analysis using dedicated software. The main interest of the 3D evaluation is to have a better visualization of bone extension in such cancers and that could also avoid unsatisfying surgical treatment later on. PATIENTS AND METHODS: A prospective study was carried out from November 2016 to September 2017. Twenty patients with head and neck squamous cell carcinoma extending to the mandible (stage 4 in the UICC classification) underwent [18F]-NaF and [18F]-FDG PET/CT. We compared the delineation of 3D quantification obtained with [18F]-NaF and [18F]-FDG PET/CT. In order to carry out this comparison, a method of visualisation and quantification of PET images was developed. This new approach was based on a process of quantification of radioactive activity within the mandibular bone that objectively defined the significant limits of this activity on PET images and on a 3D visualization. Furthermore, the spatial limits obtained by analysis of the PET/CT 3D images were compared to those obtained by histopathological examination of mandibular resection which confirmed intraosseous extension to the mandible. RESULTS: The [18F]-NaF PET/CT imaging confirmed the mandibular extension in 85% of cases and was not shown in [18F]-FDG PET/CT imaging. The [18F]-NaF PET/CT was significantly more accurate than [18F]-FDG PET/CT in 3D assessment of intraosseous extension of head and neck squamous cell carcinoma. This new 3D information shows the importance in the imaging approach of cancers. All cases of mandibular extension suspected on [18F]-NaF PET/CT imaging were confirmed based on histopathological results as a reference. CONCLUSIONS: The [18F]-NaF PET/CT 3D visualization should be included in the pre-treatment workups of head and neck cancers. With the use of a dedicated software which enables objective delineation of radioactive activity within the bone, it gives a very encouraging results. The [18F]-FDG PET/CT appears insufficient to confirm mandibular extension. This new 3D simulation management is expected to avoid under treatment of patients with intraosseous mandibular extension of head and neck cancers. However, there is also a need for a further study that will compare the interest of PET/CT and PET/MRI in this indication.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Imageamento Tridimensional , Mandíbula/diagnóstico por imagem , Neoplasias Mandibulares/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Feminino , Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Imageamento Tridimensional/métodos , Masculino , Mandíbula/patologia , Neoplasias Mandibulares/patologia , Pessoa de Meia-Idade
3.
Eur J Nucl Med Mol Imaging ; 42(9): 1459-68, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25952279

RESUMO

PURPOSE: Despite good to excellent inter-reader agreement in the evaluation of amyloid load on PET scans in subjects with Alzheimer's disease, some equivocal findings have been reported in the literature. We aimed to describe the clinical characteristics of subjects with equivocal PET images. METHODS: Nondemented subjects aged 70 years or more were enrolled from the MAPT trial. Cognitive and functional assessments were conducted at baseline, at 6 months, and annually for 3 years. During the follow-up period, 271 subjects had (18)F-AV45 PET scans. Images were visually assessed by three observers and classified as positive, negative or equivocal (if one observer disagreed). After debate, equivocal images were reclassified as positive (EP+) or negative (EP-). Scans were also classified by semiautomated quantitative analysis using mean amyloid uptake of cortical regions. We evaluated agreement among the observers, and between visual and quantitative assessments using kappa coefficients, and compared the clinical characteristics of the subjects according to their PET results. RESULTS: In 158 subjects (58.30 %) the PET scan was negative for amyloid, in 77 (28.41 %) the scan was positive and in 36 (13.28 %) the scan was equivocal. Agreement among the three observers was excellent (kappa 0.80). Subjects with equivocal images were more frequently men (58 % vs. 37 %) and exhibited intermediate scores on cognitive and functional scales between those of subjects with positive and negative scans. Amyloid load differed between the EP- and negative groups and between the EP+ and positive groups after reclassification. CONCLUSION: Equivocal amyloid PET images could represent a neuroimaging entity with intermediate amyloid load but without a specific neuropsychological pattern. Clinical follow-up to assess cognitive evolution in subjects with equivocal scans is needed.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/fisiopatologia , Amiloide/metabolismo , Cognição , Tomografia por Emissão de Pósitrons , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Feminino , Seguimentos , Humanos , Masculino , Variações Dependentes do Observador
4.
Cancer Imaging ; 13: 73-80, 2013 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-23466871

RESUMO

INTRODUCTION: Small cell lung cancer (SCLC) is an aggressive form of lung cancer with poor prognosis. Adequate staging and therapeutic evaluation is necessary for therapy planning. Fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) has been shown to be useful for staging and therapy response evaluation. The European Organization for Research and Treatment of Cancer (EORTC) and Positron Emission Tomography Response Criteria In Solid Tumors (PERCIST) criteria were compared in the evaluation of response assessment and prognostic factors were defined in a cohort of SCLC patients. METHODS: Twenty-nine consecutive patients with SCLC were included in this study. Sixteen patients had extensive disease and 13 had limited disease. All patients had chemotherapy, 21 had thoracic radiotherapy. FDG-PET/CT scans were performed before and after therapy to evaluate treatment response. Metabolic responses were assessed using the EORTC criteria and PERCIST criteria. Univariate and multivariate analysis were performed using a Cox model to investigate the association between progression-free and overall survival time with a number of covariates. RESULTS: There was perfect concordance between the EORTC and PERCIST criteria. Eight patients had a complete metabolic response (CMR), 9 had a partial metabolic response (PMR), 5 had stable metabolic disease (SMD) and 7 had progressive metabolic disease (PMD). Overall survival time in patients with CMR was significantly longer compared with patients who did not have CMR. The initial or delayed CMR and post-therapeutic standardized uptake value corrected for lean body mass were significantly associated with overall survival. CONCLUSION: CMR on post-therapeutic FDG-PET/CT in patients with SCLC is an important prognostic factor and may help decision making for therapeutic management.


Assuntos
Fluordesoxiglucose F18 , Neoplasias Pulmonares/diagnóstico por imagem , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Carcinoma de Pequenas Células do Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Prognóstico , Carcinoma de Pequenas Células do Pulmão/mortalidade , Carcinoma de Pequenas Células do Pulmão/terapia
5.
Cancer Imaging ; 12: 7-12, 2012 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-22275725

RESUMO

A 71-year-old woman was admitted to our hospital with asthenia, weight loss, fever, cognitive impairment and shortness of breath. Physical examination showed hemiparesis and cerebellar ataxia. There was no superficial lymphadenopathy. Blood tests showed raised levels of C-reactive protein and lactate dehydrogenase. Bone marrow aspiration and biopsy were negative. [18F]fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) showed intense uptake within a right apical nodule and intense and diffuse uptake of FDG in the lungs without corresponding structural CT abnormality. Lung biopsy showed intravascular large B-cell lymphoma (IVLBCL). FDG-PET findings in IVLBCL and causes of diffuse FDG lung uptake with and without CT abnormalities are discussed.


Assuntos
Capilares/diagnóstico por imagem , Radioisótopos de Flúor/farmacocinética , Fluordesoxiglucose F18/farmacocinética , Pulmão/irrigação sanguínea , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/farmacocinética , Idoso , Anticorpos Monoclonais Murinos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Medula Óssea/patologia , Encéfalo/diagnóstico por imagem , Transtornos Cognitivos/etiologia , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Reações Falso-Negativas , Feminino , Febre/etiologia , Humanos , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Paresia/etiologia , Prednisona/administração & dosagem , Rituximab , Distribuição Tecidual , Tomografia Computadorizada por Raios X , Vincristina/administração & dosagem
6.
Q J Nucl Med Mol Imaging ; 55(3): 324-33, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21532544

RESUMO

AIM: We assessed in this study the influence of contrast-enhanced CT (ceCT) on PET/CT interpretation and PET/CT on ceCT interpretation in patients with lymphoma, before and after chemotherapy. METHODS: Fifty patients with Hodgkin disease (N.=17) or non-Hodgkin lymphomas (N.=33) were assessed before and after chemotherapy. PET/CT were performed 60 minutes after injection of FDG. Iopamidol was then injected and followed, 50 seconds later, by another CT. PET images were successively reconstructed using non-enhanced CT (PET-) and ceCT (PET+). Four nuclear physicians rated PET- and PET+ in random order. Three radiologists initially rated ceCT alone and then ceCT along with PET+. RESULTS: Before chemotherapy, global agreement (GA) was 99% (k=0.96) when PET- was compared to PET+. Nine (5%) lesions were discordant, 5 according to PET- and 4 to PET+. After chemotherapy, GA was 99% (k=0.91). Eight (15%) lesions were discordant, 3 according to PET- and 5 to PET+. Before chemotherapy, GA was 97% (k=0.91) when ceCT was compared to ceCT with PET+. Twenty-one (12%) lesions were discordant, 16 when ceCT were analyzed alone and 5 when ceCT was analyzed with PET+. After chemotherapy, GA was 95% (k=0.76). All 30 (35%) discordant lesions were positive according to ceCT alone. A significant difference between the 2 procedures was found in the pelvis and in the groin (P<0.05). CONCLUSION: PET+ did not differ from PET-, before and after chemotherapy. Fewer abnormalities were observed, when ceCT was analyzed with PET+, particularly after chemotherapy, due to residual masses that are better analyzed with functional imaging.


Assuntos
Linfoma/diagnóstico por imagem , Adulto , Idoso , Meios de Contraste , Feminino , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/tratamento farmacológico , Humanos , Linfoma/tratamento farmacológico , Linfoma não Hodgkin/diagnóstico por imagem , Linfoma não Hodgkin/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Medicina Nuclear , Variações Dependentes do Observador , Tomografia por Emissão de Pósitrons , Interpretação de Imagem Radiográfica Assistida por Computador , Radiologia , Tomografia Computadorizada por Raios X
7.
Gynecol Obstet Fertil ; 38(4): 244-9, 2010 Apr.
Artigo em Francês | MEDLINE | ID: mdl-20359931

RESUMO

OBJECTIVES: Assessment of prognostic value of pretherapeutic (18)F-FDG PET/CT (PET). PATIENTS AND METHODS: Retrospective study of 53 patients with invasive uterine cervix carcinoma. Each patient has been evaluated with pretherapeutic whole-body FDG PET/CT and pelvic MRI. Minimal follow-up lasted for 1 year. On PET/CT, we have visually analyzed metabolism of primary tumor, pelvic and para-aortic lymph nodes in comparison with surrounding structures. We have compared prognostic factors as pretherapeutic haemoglobin rate, FIGO staging, MRI and PET/CT data using Mann-Whitney univariate analysis and Cox multivariate analysis. RESULTS: Para-aortic lymph node abnormal uptake on PET/CT was the only independent predictor of progression-free survival. Pelvic lymph node involvement on PET/CT was the only independent predictor of overall survival. MRI did not provide any additional information. DISCUSSION AND CONCLUSION: Lymph node involvement visually assessed by (18)F-FDG PET/CT was the most significant prognostic factor for overall and progression-free survival.


Assuntos
Adenocarcinoma Mucinoso/diagnóstico por imagem , Carcinoma de Células Escamosas/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Adenocarcinoma Mucinoso/mortalidade , Adenocarcinoma Mucinoso/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Intervalo Livre de Doença , Feminino , Fluordesoxiglucose F18 , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Prognóstico , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/patologia
8.
Cephalalgia ; 27(9): 1043-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17666084

RESUMO

The aim of this study was to describe the abnormalities associated with migraine aura lasting 1-24 h in children as shown by EEG, trancranial Doppler (TCD) and single photon emission computed tomography (SPECT). In this retrospective study, 11 patients each underwent EEG, TCD and brain SPECT on the day of admission and the day thereafter. On the day of admission, the migrainous hemisphere of all patients showed that the mean velocities were decreased in the middle cerebral artery by TCD, slow-wave abnormalities were recorded after several hours of aura by EEG and the SPECT showed hypoperfusion. On the day after, in the same hemisphere, slow waves were recorded only in the occipital area by EEG, and SPECT showed slight hyperperfusion. In these patients, there was a clear sequence of EEG, TCD and SPECT abnormalities.


Assuntos
Transtornos Cerebrovasculares/diagnóstico , Transtornos Cerebrovasculares/fisiopatologia , Eletroencefalografia/métodos , Enxaqueca com Aura/diagnóstico , Enxaqueca com Aura/fisiopatologia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Ultrassonografia Doppler Transcraniana/métodos , Adolescente , Criança , Feminino , Humanos , Masculino , Estudos Retrospectivos
9.
J Clin Endocrinol Metab ; 92(7): 2487-95, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17426102

RESUMO

BACKGROUND: Serum thyroglobulin (Tg) is the marker of differentiated thyroid cancer after initial treatment and TSH stimulation increases its sensitivity for the diagnosis of recurrent disease. AIM: The goal of the study is to compare the diagnostic values of seven methods for serum Tg measurement for detecting recurrent disease both during L-T4 treatment and after TSH stimulation. METHODS: Thyroid cancer patients who had no evidence of persistent disease after initial treatment (total thyroidectomy and radioiodine ablation) were studied at 3 months on L-T4 treatment (Tg1) and then at 9-12 months after withdrawal or recombinant human TSH stimulation (Tg2). Sera with anti-Tg antibodies or with an abnormal recovery test result were excluded from Tg analysis with the corresponding assay. The results of serum Tg determination were compared to the clinical status of the patient at the end of follow-up. RESULTS: Thirty recurrences were detected among 944 patients. A control 131I total body scan had a low sensitivity, a low specificity, and a low clinical impact. Assuming a common cutoff for all Tg assays at 0.9 ng/ml, sensitivity ranged from 19-40% and 68-76% and specificity ranged from 92-97% and 81-91% for Tg 1 and Tg2, respectively. Using assays with a functional sensitivity at 0.2-0.3 ng/ml, sensitivity was 54-63% and specificity was 89% for Tg1. Using the two methods with a lowest functional sensitivity at 0.02 and 0.11 ng/ml resulted in a higher sensitivity for Tg1 (81% and 78%), but at the expense of a loss of specificity (42% and 63%); finally, for these two methods, using an optimized functional sensitivity according to receiver operating characteristic curves at 0.22 and 0.27 ng/ml resulted in a sensitivity at 65% and specificity at 85-87% for Tg1. CONCLUSION: Using an assay with a lower functional sensitivity may give an earlier indication of the presence of Tg in the serum on L-T4 treatment and may be used to study the trend in serum Tg without performing any TSH stimulation. Serum Tg determination obtained after TSH stimulation still permits a more reliable assessment of cure and patient's reassurance.


Assuntos
Carcinoma Papilar, Variante Folicular/sangue , Carcinoma Papilar, Variante Folicular/diagnóstico por imagem , Química Clínica/métodos , Tireoglobulina/análise , Tireoglobulina/sangue , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Adulto , Biomarcadores/sangue , Carcinoma Papilar, Variante Folicular/terapia , Feminino , Seguimentos , Humanos , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/diagnóstico por imagem , Estudos Prospectivos , Cintilografia , Indução de Remissão , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/terapia
10.
Gynecol Obstet Fertil ; 34(7-8): 619-21, 2006.
Artigo em Francês | MEDLINE | ID: mdl-16854611

RESUMO

Paget's disease of the vulva is difficult to diagnose, as far as the extent of this lesion is concerned, since it is often coupled with invasive adenocarcinoma of the vulva. Thus, we present two cases of Paget's disease of the vulva, with use of sentinel lymph node analysis- a non-validated technique in this very context. Evaluation of sentinel lymph node may be useful in case of micro-invasive Paget's disease.


Assuntos
Doença de Paget Extramamária/diagnóstico , Biópsia de Linfonodo Sentinela , Doenças da Vulva/diagnóstico , Adenocarcinoma/complicações , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Doença de Paget Extramamária/patologia , Doença de Paget Extramamária/cirurgia , Doenças da Vulva/patologia , Doenças da Vulva/cirurgia , Neoplasias Vulvares/complicações
11.
Gynecol Obstet Fertil ; 34(5): 437-59, 2006 May.
Artigo em Francês | MEDLINE | ID: mdl-16821280

RESUMO

CONTEXT: The validity of the recommendations is based on their actualisation as well as on the quality of the initial elaboration process. Therefore the "Standards, Options and Recommendations" (SOR) from the National French federation of comprehensive cancer centres (FNCLCC) has set up a literature monitoring process. OBJECTIVES: To identify new data, which are likely to modify existing recommendations, evaluate their impact and inform potential users on their validity. METHODS: The monitoring process is based on 3 main steps lead in collaboration with experts: collect data, select and classify information and analyse information. Analysis of information consists of comparing the conclusions of new data with the conclusions of the initial report and then to identify the recommendations that need to be updated. RESULTS: This article presents the 2005 monitoring report concerning "the use of positron emission tomography with FDG in the management of breast cancer, ovarian cancer and uterin cancer". Following the monitoring process,all the existing recommendations (initial report from 2003) are still valid. However three modifications have been proposed by the working group: 1) increased level of evidence concerning the use of PET-scan for suspicion of local or metastatic recurrence (option, level of evidence: A); 2) a new option for the use of PET-scan for revealed cervix cancer recurrence, especially for the therapeutic decision strategy (level of evidence: B2); and 3) new formulation (less strict) of the recommendation concerning the use of PET-scan in the management of endometrial cancer.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias Ovarianas/diagnóstico por imagem , Guias de Prática Clínica como Assunto , Tomografia Computadorizada de Emissão/métodos , Tomografia Computadorizada de Emissão/normas , Neoplasias Uterinas/diagnóstico por imagem , Feminino , Fluordesoxiglucose F18 , França , Humanos , Metanálise como Assunto , Metástase Neoplásica , Qualidade da Assistência à Saúde , Compostos Radiofarmacêuticos
13.
Nucl Med Commun ; 24(8): 907-14, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12869824

RESUMO

Patient morphology, as well as the acquisition and reconstruction parameters, may influence the evaluation of the left ventricular volume (LVV) and left ventricular ejection fraction (LVEF) using gated single-photon emission computed tomography (SPECT). The purpose of this study was to examine the influence of gender and reconstruction filter on the measurement of LVV and LVEF using 201Tl gated SPECT. Using a static torso phantom, a female shape was created by the addition of two saline solution-filled balloons fixed on the anterior rib cage. The following parameters were similar for all acquisitions: 90 degrees dual-head gamma camera; 32 projections; 64x64 matrix (pixel size=6.77x6.77 mm); two 20% energy windows centred at 70 and 167 keV. The following acquisition times were tested: 1.25, 10, 20, 30 and 40 s per projection, leading to a total of 10 successive acquisitions. The effect of over-sampling was tested by 2.5 post-acquisition zooming. All SPECT images were successively reconstructed using filtered back-projection with Butterworth and Wiener filters. The effect of gender and reconstruction filter was also studied in 30 patients (15 males and 15 females) with a low likelihood of coronary artery disease. LVVs were calculated using QGS software. By multivariate analysis, the following factors influenced the accuracy of phantom measurement using QGS software: zooming (F=49, P<0.0001), phantom shape (F=61, P<0.0001) and filter type (F=240, P<0.0001). LVV was underestimated in the female shape phantom, even when using the Wiener filter. In patients, LVV and LVEF measurements were independently influenced by gender (P<0.0001) and filter (P<0.0001), but not by zooming. In conclusion, it was demonstrated that LVV was significantly decreased in the female shape phantom, suggesting a significant impact of breast interposition. This underestimation was minimized by use of the Wiener filter. In patients, the impact of the Wiener filter on the assessment of LVVs and LVEF was powerful, but independent of gender, and failed to correct the underestimation of LVVs and the overestimation of LVEF in females.


Assuntos
Volume Cardíaco , Doença da Artéria Coronariana/diagnóstico por imagem , Imagem do Acúmulo Cardíaco de Comporta/métodos , Interpretação de Imagem Assistida por Computador/métodos , Processamento de Sinais Assistido por Computador , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Algoritmos , Doença da Artéria Coronariana/complicações , Imagem do Acúmulo Cardíaco de Comporta/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores Sexuais
14.
Eur J Heart Fail ; 3(6): 709-16, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11738223

RESUMO

BACKGROUND: Exercise-induced ST-segment elevation was proposed as a marker of myocardial viability after a recent myocardial infarction. AIMS: The aim of this study was to evaluate whether exercise-induced ST segment elevation is related to viability or to left ventricular dysfunction in patients with history of old Q wave myocardial infarction. METHODS: Fifty patients (43 men, age 57+/-11 years) were studied 31+/-49 months after a Q wave myocardial infarction. They all underwent stress, reinjection-redistribution, and late redistribution Tl-201 SPECT, completed by equilibrium radionuclide angiography. Viability was defined by defect reversibility or significant (>60%) persistent Tl-201 uptake in dyssinergic segments on late redistribution SPECT. Relative post-exercise and reinjection-redistribution LV volumes were calculated using validated software (QGS). RESULTS: Twenty-one out of 50 patients (42%, G1) had significant stress-induced ST-elevation (>1 mm 80 ms after J point in at least 2 ECG leads with Q wave), and 29/50 (58%, G2) did not. Seventeen out of 50 patients (34%) demonstrated myocardial viability on late redistribution scan. The diagnostic accuracy of exercise-induced ST-elevation was only 52% for viability assessment. Significant LVEF reduction and increased relative LV volumes were observed in G1 compared to G2 (LVEF: 39+/-10% vs. 49+/-11%, P=0.003; post-stress LV volume: 134+/-98 ml vs. 81+/-41 ml, P<0.02; reinjection-redistribution LV volume: 123+/-86 ml vs. 79+/-40 ml; P<0.02). Perfusion defects were similar in G1 and G2 (post-exercise: 38+/-12% vs. 37+/-14%, ns; reinjection-redistribution: 31+/-11% vs. 30+/-11%, ns; late redistribution: 30+/-10% vs. 28+/-11%, ns). CONCLUSION: These results suggest that, in patients with history of myocardial infarction, exercise-induced ST-segment elevation is not related to persistent myocardial viability but is associated to left ventricular dysfunction.


Assuntos
Eletrocardiografia Ambulatorial , Exercício Físico , Viabilidade Fetal/fisiologia , Infarto do Miocárdio/fisiopatologia , Disfunção Ventricular Esquerda/fisiopatologia , Idoso , Análise de Variância , Discinesias/complicações , Discinesias/diagnóstico por imagem , Teste de Esforço , Feminino , França , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico por imagem , Perfusão , Valor Preditivo dos Testes , Angiografia Cintilográfica , Sensibilidade e Especificidade , Volume Sistólico/fisiologia , Radioisótopos de Tálio , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/diagnóstico por imagem
15.
J Nucl Cardiol ; 8(3): 332-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11391303

RESUMO

BACKGROUND: Increased lung uptake during exercise thallium 201 single photon emission computed tomography is related to left ventricular dysfunction and extent of coronary artery disease (CAD). We studied the influence of the lung region of interest (ROI), used to quantify Tl-201 lung uptake, on the diagnostic value of the lung-to-heart uptake ratio (LHR) in detecting CAD with Tl-201 myocardial single photon emission computed tomography. METHODS AND RESULTS: We retrospectively studied 152 consecutive patients referred to our center for stress Tl-201 scanning. Of these, 116 had proven multivessel CAD and 36 had either normal findings on coronary angiogram or a low likelihood (<5%) of CAD. Poststress quantitative analysis was performed from a 4 x 4-pixel ROI over the hottest myocardial region, an 8 x 8-pixel left lung ROI, an 8 x 8-pixel right lung ROI, and a manual ROI encompassing the whole right lung. The LHR was calculated for each lung ROI. Right LHR (R-LHR) provided the best interobserver and intraobserver reproducibility. R-LHR and total R-LHR values were significantly higher in patients with CAD. Only history of myocardial infarction significantly influenced the R-LHR measurement. CONCLUSIONS: The methodology of LHR measurement significantly influences the clinical contribution of Tl-201 lung uptake evaluation. Optimal reproducibility and diagnostic accuracy are provided by a right lung ROI.


Assuntos
Testes Diagnósticos de Rotina/métodos , Coração/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Tálio , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Intervalos de Confiança , Doença das Coronárias/diagnóstico , Técnicas de Diagnóstico Cardiovascular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
16.
J Nucl Med ; 40(4): 513-21, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10210208

RESUMO

UNLABELLED: The effect of filtering and zooming on 201TI-gated SPECT was evaluated in patients with major myocardial infarction. METHODS: Rest thallium (TI)-gated SPECT was performed with a 90 degrees dual-head camera, 4 h after injection of 185 MBq 201TI in 32 patients (mean age 61 +/- 11 y) with large myocardial infarction (33% +/- 17% defect on bull's eye). End diastolic volume (EDV), end systolic volume (ESV) and left ventricular ejection fraction (LVEF) were calculated using a commercially available semiautomatic validated software. First, images were reconstructed using a 2.5 zoom, a Butterworth filter (order = 5) and six Nyquist cutoff frequencies: 0.13 (B5.13), 0.15 (B5.15), 0.20 (B5.20), 0.25 (B5.25), 0.30 (B5.30) and 0.35 (B5.35). Second, images were reconstructed using a zoom of 1 and a Butterworth filter (order = 5) (cutoff frequency 0.20 [B5.20Z1]) (total = 32 x 7 = 224 reconstructions). LVEF was calculated in all patients using equilibrium radionuclide angiocardiography (ERNA). EDV, ESV and LVEF were measured with contrast left ventriculography (LVG). RESULTS: LVEF was 39% +/- 2% (mean +/- SEM) for ERNA and 40% +/- 13% for LVG (P = 0.51). Gated SPECT with B5.20Z2.5 simultaneously offered a mean LVEF value (39% +/- 2%) similar to ERNA (39% +/- 2%) and LVG (40% +/- 3%), optimal correlations with both ERNA (r = 0.83) and LVG (r = 0.70) and minimal differences with both ERNA (-0.9% +/- 7.5% [mean +/- SD]) and LVG (1.1% +/- 10.5%). As a function of filter and zoom choice, correlation coefficients between ERNA or LVG LVEF, and gated SPECT ranged from 0.26 to 0.88; and correlation coefficients between LVG and gated SPECT volumes ranged from 0.87 to 0.94. There was a significant effect of filtering and zooming on EDV, ESV and LVEF (P < 0.0001). Low cutoff frequency (B5.13) overestimated LVEF (P < 0.0001 versus ERNA and LVG). Gated SPECT with 2.5 zoom and high cutoff frequencies (B5.15, B5.20, B5.25, B5.30 and B5.35) overestimated EDV and ESV (P < 0.04) compared with LVG. This volume overestimation with TI-gated SPECT in patients with large myocardial infarction was correlated to the infarct size. A zoom of 1 underestimated EDV, ESV and LVEF compared with a 2.5 zoom (P < 0.02). CONCLUSION: Accurate LVEF measurement is possible with TI-gated SPECT in patients with major myocardial infarction. However, filtering and zooming greatly influence EDV, ESV and LVEF measurements, and TI-gated SPECT overestimates left ventricular volumes, particularly when the infarct size increases.


Assuntos
Imagem do Acúmulo Cardíaco de Comporta , Infarto do Miocárdio/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Feminino , Coração/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Angiografia Cintilográfica/métodos , Volume Sistólico , Radioisótopos de Tálio , Função Ventricular Esquerda
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