RESUMO
El hiperparatiroidismo persistente/recurrente representa un desafío en la localización del tejido paratiroideo hiperfuncionante. En esta subpoblación, los métodos convencionales ofrecen un menor rédito diagnóstico. La 18F-colina PET/TC podría ser una buena alternativa dada su mejor resolución espacial, capacidad de detectar glándulas ectópicas y la conjunción de la imagen molecular y anatómica. Sin embargo, la evidencia en este subgrupo de pacientes es escasa. Objetivo: evaluar la utilidad de la 18F-colina PET/TC como método de localización en el hiperparatiroidismo persistente o recurrente. Materiales y métodos: se analizaron los pacientes con 18F-colina PET/TC para hiperparatiroidismo entre diciembre de 2015 y enero de 2018 en un centro terciario de alto volumen. Se analizaron el número de lesiones, su localización, tamaño y el Standard Uptake Value máximo (SUV max) en las imágenes tempranas y tardías. Se compararon los resultados con los métodos convencionales. Resultados: 7 de 15 pacientes habían sido operados previamente (persistentes/recurrentes). La 18F-colina PET/TC detectó 6/7 casos (83,33%), la ecografía cervical 1/4 (25%) y el SPECT de paratiroides y la resonancia nuclear magnética 2/5 (40%). El SUV max obtenido fue variable, en la mitad de los casos a los 10 minutos y en los restantes a la hora; el tamaño promedio de las lesiones fue 8,61 mm (6-12 mm). Conclusiones: la 18F-colina PET/TC muestra una alta tasa de detección en los pacientes con hiperparatiroidismo persistente/recurrente. La combinación del comportamiento biológico del PET con los hallazgos morfológicos aportados por la TC con contraste endovenoso le ofrecería ventajas sobre otros estudios que podrían posicionarlo como método de primera línea en esta subpoblación. (AU)
Persistent or recurrent hyperparathyroidism represents a challenge regarding the localization of the hyper-functioning parathyroid tissue. In this subpopulation of hyperpharathyroid patients, conventional methods have a low diagnostic yield. The 18F-choline PET /CT could be a good alternative given its better spatial resolution, ability to detect ectopic glands, and the conjunction of the molecular and anatomical image. However, the evidence in this subgroup of patients is limited. Objective: to evaluate the utility of 18F-choline PET/ CT as a localization method in persistent or recurrent hyperparathyroidism. Materials and methods: patients with 18F-choline PET / CT for hyperparathyroidism between December 2015 and January 2018 in a high-volume tertiary center were included. The number of lesions, and their location, size, and maximum Standard Uptake Value (SUV) in the early and late images were analyzed. The results were compared to conventional methods. Results: 7 of 15 patients had been previously operated (persistent/recurrent). 18F-choline PET / CT detected 6/7 cases (83,33%), cervical ultrasound 1/4 (25%) and parathyroid SPECT and magnetic resonance 2/5 (40%). The maximum SUV was variable, one half at 10 minutes and the other half at 60 minutes; the average size of the lesions was 8.61 mm (6-12 mm). Conclusions: 18F-Choline PET / CT shows a high detection rate in patients with persistent / recurrent hyperparathyroidism. The combination of the biological behavior of PET with the morphological findings provided by CT with intravenous contrast would offer advantages over other studies that could position it as a first line method in this subpopulation. (AU)
Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Hiperparatireoidismo Primário/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/estatística & dados numéricos , Recidiva , Vitamina D/sangue , Espectroscopia de Ressonância Magnética/estatística & dados numéricos , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Colina/análogos & derivados , Ultrassonografia/estatística & dados numéricos , Fluordesoxiglucose F18 , Hiperparatireoidismo Primário/cirurgia , Hiperparatireoidismo Primário/complicações , Hiperparatireoidismo Primário/etiologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Metionina/análogos & derivadosRESUMO
Infecções por Plasmodium spp. podem acarretar em complicações pulmonares (1 a 40% dos casos), que podem resultar no desenvolvimento da síndrome do desconforto respiratório agudo (SDRA). Esta síndrome é caracterizada por inflamação aguda, lesão do endotélio alveolar e do parênquima pulmonar, disfunção e aumento da permeabilidade da barreira alvéolo-capilar pulmonar e, consequente, formação de efusão pleural. Neste sentido, os mecanismos de regulação da permeabilidade das células endoteliais e as junções interendoteliais têm papel crítico na manutenção do endotélio pulmonar. O objetivo do estudo foi determinar precocemente o desenvolvimento da SDRA associada à malária por tomografia computadorizada por emissão de fóton único (SPECT/CT), além de identificar alterações nas junções interendoteliais das células endoteliais pulmonares primárias de camundongos DBA/2 (CEPP-DBA/2), após contato com os eritrócitos parasitados de Plasmodium berghei ANKA (EP-PbA). Os nossos resultados demonstraram que é possível identificar alterações na aeração pulmonar no 5° e 7° dia após a infecção e, consequentemente, diferenciar os animais que desenvolveriam SDRA daqueles que evoluiriam para hiperparasitemia (HP). Além disso, observamos em CEPP-DBA/2 que o contato direto com EP-PbA aumenta da abertura das junções interendoteliais e da permeabilidade vascular. Assim, avaliamos a diminuição da expressão das proteínas das junções interendoteliais que contribuem para o aumento da permeabilidade vascular, por imunofluorescência e Western Blot. Apesar da SDRA ter sido identificada há mais de 50 anos, ainda não se conhece formas de diagnóstico precoce e os mecanimos efetivos de desenvolvimento desta enfermidade, que permitam um tratamento efetivo e que evite a morte do paciente. Portanto, sugere-se que a técnica de SPECT/CT seja uma importante ferramenta de diagnóstico para identificação precoce de SDRA associado a malária
Infections by Plasmodium spp. can lead to pulmonary complications (1 to 40% of the cases), that can result in the development of acute respiratory distress syndrome (ARDS). This syndrome is characterized by the acute inflammation, injury of the alveolar endothelium and pulmonary parenchyma, dysfunction and increased permeability of the pulmonary alveolar-capillary barrier and, consequently, formation of pleural effusion. In this aspect, mechanisms of regulation of endothelial cell permeability and interendothelial junctions play a critical role in the maintenance of the pulmonary endothelium. The present study aimed to determine the early development of single-photon emission computed tomography (SPECT/CT) associated malaria ARDS in addition to identifying changes in the interendothelial junctions of the primary pulmonary endothelial cells of DBA/2 mice (CEPP-DBA/2) after contact with erythrocytes infected with Plasmodium berghei ANKA (EP-PbA). Our results demonstrated that is possible to identify changes in lung aeration on the 5th and 7th day after infection and, consequently, differentiate the animals that should develop ARDS from those that would evolve to hyperparasitemia (HP). In addition, we observed in CEPP-DBA/2 that direct contact with EP-PbA increases the opening of the interendothelial junctions and vascular permeability. Thus, we evaluated that decrease the expression of interendothelial junction proteins contribute to the increase of vascular permeability, by immunofluorescence and Western Blot. Although ARDS was identified more than 50 years ago, it is not yet known what forms of early diagnosis, and the effective mechanisms of development of this disease, that allow an effective treatment and that prevent the death of the patient. Therefore, it is suggested that the SPECT/CT technique is a valuable tool to promote the early identification of ARDS associated with malaria
Assuntos
Animais , Masculino , Camundongos , Síndrome do Desconforto Respiratório/tratamento farmacológico , Permeabilidade Capilar , Malária/transmissão , Plasmodium berghei , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Edema , Pulmão/anormalidadesRESUMO
BACKGROUND: Recent studies have shown that myocardial perfusion imaging (MPI) in cadmium-zinc-telluride (CZT) cameras allow faster exams with less radiation dose but there are little data comparing its prognosis information with that of dedicated cardiac Na-I SPECT cameras OBJECTIVE: The objective of this study is to compare the prognostic value of MPI using an ultrafast protocol with low radiation dose in a CZT-SPECT and a traditional one. METHODS: Group 1 was submitted to a two-day MIBI protocol in a conventional camera, and group 2 was submitted to a 1-day MIBI protocol in CZT camera. MPI were classified as normal or abnormal, and perfusion scores were calculated. Propensity score matching methods were performed RESULTS: 3554 patients were followed during 33±8 months. Groups 1 and 2 had similar distribution of age, gender, body mass index, risk factors, previous revascularization, and use of pharmacological stress. Group 1 had more abnormal scans, higher scores than group 2. Annualized hard events rate was higher in group 1 with normal scans but frequency of revascularization was similar to normal group 2. Patients with abnormal scans had similar event rates in both groups CONCLUSION: New protocol of MPI in CZT-SPECT showed similar prognostic results to those obtained in dedicated cardiac Na-I SPECT camera, with lower prevalence of hard events in patients with normal scan.
Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Morte Súbita Cardíaca/epidemiologia , Câmaras gama/estatística & dados numéricos , Imagem de Perfusão do Miocárdio/instrumentação , Tomografia Computadorizada de Emissão de Fóton Único/instrumentação , Brasil/epidemiologia , Cádmio/efeitos da radiação , Comorbidade , Doença da Artéria Coronariana/cirurgia , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio/estatística & dados numéricos , Reprodutibilidade dos Testes , Medição de Risco/métodos , Sensibilidade e Especificidade , Taxa de Sobrevida , Telúrio/efeitos da radiação , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Resultado do Tratamento , Zinco/efeitos da radiaçãoRESUMO
Myocardial perfusion imaging is widely used for the risk stratification of coronary artery disease. In view of its cost, besides radiation issues, judicious evaluation of the appropriateness of its indications is essential to prevent an unnecessary economic burden on the health system. We evaluated, at a tertiary-care, public Brazilian hospital, the appropriateness of myocardial perfusion scintigraphy indications, and estimated the budget impact of applying appropriateness criteria. An observational, cross-sectional study of 190 patients with suspected or known coronary artery disease referred for myocardial perfusion imaging was conducted. The appropriateness of myocardial perfusion imaging indications was evaluated with the Appropriate Use Criteria for Cardiac Radionuclide Imaging published in 2009. Budget impact analysis was performed with a deterministic model. The prevalence of appropriate requests was 78%; of inappropriate indications, 12%; and of uncertain indications, 10%. Budget impact analysis showed that the use of appropriateness criteria, applied to the population referred to myocardial perfusion scintigraphy within 1 year, could generate savings of $ 64,252.04 dollars. The 12% inappropriate requests for myocardial perfusion scintigraphy at a tertiary-care hospital suggest that a reappraisal of MPI indications is needed. Budget impact analysis estimated resource savings of 18.6% with the establishment of appropriateness criteria for MPI.
Assuntos
Orçamentos/estatística & dados numéricos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/economia , Fidelidade a Diretrizes/economia , Imagem de Perfusão do Miocárdio/economia , Tomografia Computadorizada de Emissão de Fóton Único/economia , Brasil/epidemiologia , Doença da Artéria Coronariana/epidemiologia , Estudos Transversais , Países em Desenvolvimento , Feminino , Fidelidade a Diretrizes/estatística & dados numéricos , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio/normas , Imagem de Perfusão do Miocárdio/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Prevalência , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Revisão da Utilização de Recursos de SaúdeRESUMO
BACKGROUND: Annual mortality rate can range from <1% for patients with normal myocardial perfusion by SPECT to >5% based on a high-risk Duke treadmill score (DTS). Information on the prognosis of patients with the combination of HRDTS and normal SPECT is limited and is the purpose of this study. METHODS: Data from a large nuclear cardiology registry (n = 17,972 patients) were reviewed. A total of 340 had HRDTS (score ≤ -11) while undergoing SPECT. Combined cardiovascular mortality and non-fatal myocardial infarction (MI) and cardiovascular mortality alone were available in 310 patients at a mean follow-up of 4.01 ± 1.5 years. RESULTS: The majority of the patients had abnormal SPECT (n = 270, 71%). The abnormal SPECT patients compared to the normal were older (65.6 vs 62.8 years of age; P = .025), more likely to have abnormal left ventricular ejection fraction (26.1% vs 0%; P < .0001), known coronary artery disease (CAD, 35.9% vs 7.8%; P < .0001) and lower DTS (-14.5 vs -13.2; P = .0006), Kaplan-Meier survival analysis demonstrated a significantly lower cardiovascular mortality (5.4% vs 0%, P = .02) and combined outcome of MI and cardiovascular mortality (15% vs 4.4%, P = .009) in patients with normal versus abnormal SPECT. CONCLUSIONS: High-risk DTS is associated with abnormal perfusion SPECT in most patients, but nearly one-third of the patients had normal perfusion. Patients with a normal SPECT had a lower cardiovascular event rates.
Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Morte Súbita Cardíaca/epidemiologia , Imagem de Perfusão do Miocárdio/estatística & dados numéricos , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/mortalidade , Idoso , Brasil/epidemiologia , Causalidade , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Volume Sistólico , Taxa de SobrevidaRESUMO
BACKGROUND: The American College of Cardiology/American Society of Nuclear Cardiology published revised appropriate use criteria (AUC) for SPECT MPI in 2009. We assessed adherence to these guidelines and factors associated with inappropriate utilization at the University Medical Center. METHODS: The AUC was applied retrospectively to 420 SPECT MPI studies. Two-sample t test, Fisher's exact test, and multivariable logistic regression models were used for analysis. RESULTS: There were 322 appropriate (86%) and 54 (14%) inappropriate studies. The odds of having an inappropriate test increased with younger age (P < .001) and female gender (P < .001). Subjects with diabetes (P = .007) and chest pain (P < .001) were less likely to have an inappropriate test. Academic outpatients were three times more likely to have an inappropriate study (P = .123), while community PCPs were 5.6 times (P = .011) and community cardiologists eight times more likely to order inappropriate tests (P = .031). CONCLUSIONS: Inappropriate SPECT MPI in low risk younger women is an important issue on the USA-Mexico border. Initiatives to reduce inappropriate SPECT MPI should focus on a few indications and evaluation of cardiovascular symptoms in younger age women in outpatient/community practices.
Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Fidelidade a Diretrizes/estatística & dados numéricos , Imagem de Perfusão do Miocárdio/estatística & dados numéricos , Imagem de Perfusão do Miocárdio/normas , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Tomografia Computadorizada de Emissão de Fóton Único/normas , Procedimentos Desnecessários/estatística & dados numéricos , Distribuição por Idade , Cardiologia/normas , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etnologia , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Área Carente de Assistência Médica , México/epidemiologia , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/normas , Padrões de Prática Médica/estatística & dados numéricos , Prevalência , Distribuição por Sexo , Estados Unidos/epidemiologia , Procedimentos Desnecessários/normas , Revisão da Utilização de Recursos de SaúdeAssuntos
Calcinose/diagnóstico por imagem , Calcinose/epidemiologia , Doença da Artéria Coronariana/epidemiologia , Diabetes Mellitus/epidemiologia , Endotélio Vascular/diagnóstico por imagem , Adulto , Comorbidade , Doença da Artéria Coronariana/diagnóstico por imagem , Cuba/epidemiologia , Diabetes Mellitus/diagnóstico por imagem , Feminino , Humanos , Masculino , Imagem de Perfusão do Miocárdio/estatística & dados numéricos , Prevalência , Medição de Risco , Fatores de Risco , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricosRESUMO
BACKGROUND: Coronary artery disease is a leading cause of death among diabetics, and silent ischemia is a major concern in patients with diabetes mellitus (DM). METHODS: To detect the prevalence of ischemia in diabetics by myocardial perfusion imaging (MPI), and compare it to a control group without DM but with coronary risk factors, as well as to explore the relationship between silent ischemia, endothelial dysfunction, and coronary calcium, 59 patients (Group I) and 42 controls (Group II) were included. All underwent clinical and laboratory evaluations, gated MPI, brachial artery vasodilation measured by ultrasonography, and coronary calcium score (CCS). RESULTS: Twenty diabetics showed perfusion defects, vs seven controls (P = .04). There was no significant difference between both groups regarding the brachial artery vasodilator responsiveness: 4.49% ± 4.26% (diabetics) vs 4.70% ± 4.98% (controls). Mean CCS was 74 in diabetics vs five in controls (P = .01). The only risk factor significantly associated with an abnormal MPI was the presence of diabetes (P = .03). In the whole population of patients and in diabetics, the abnormal endothelium-dependent vasodilation, the CCS >100, and the cholesterol/HDL ratio >4, showed an OR >1. CCS exhibited the higher OR among the whole population: OR 2.15 [95% CI 0.42-10.99]; while for diabetics it was the cholesterol/HDL ratio: OR 3.95 [95% CI 0.71-21.84]. CONCLUSIONS: Reversible perfusion defects and coronary calcium are more frequent in diabetics. CCS, abnormal endothelium-dependent vasodilation, and cholesterol/HDL ratio higher than 4, showed an association with perfusion abnormalities in asymptomatic diabetics.
Assuntos
Calcinose/diagnóstico por imagem , Calcinose/epidemiologia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/epidemiologia , Diabetes Mellitus/diagnóstico por imagem , Diabetes Mellitus/epidemiologia , Endotélio Vascular/diagnóstico por imagem , Adulto , Comorbidade , Cuba/epidemiologia , Feminino , Humanos , Masculino , Imagem de Perfusão do Miocárdio/estatística & dados numéricos , Prevalência , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricosRESUMO
This article reports on the development of a prototype of a SPECT tomograph system for online dosimetry in BNCT based on LaBr(3)(Ce) scintillation detectors. The setup shielding was optimized to be used in the accelerator based BNCT facility of the University of Birmingham. The system was designed and built. An image of a (241)Am point source was reconstructed. A projection of a phantom with two tumors with 400 microg/g of (10)B was measured at the BNCT facility.
Assuntos
Terapia por Captura de Nêutron de Boro/estatística & dados numéricos , Planejamento da Radioterapia Assistida por Computador/estatística & dados numéricos , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Boro/uso terapêutico , Terapia por Captura de Nêutron de Boro/instrumentação , Inglaterra , Desenho de Equipamento , Humanos , Isótopos/uso terapêutico , Neoplasias/radioterapia , Imagens de Fantasmas/estatística & dados numéricos , Radiossensibilizantes/uso terapêutico , Planejamento da Radioterapia Assistida por Computador/instrumentação , Tomografia Computadorizada de Emissão de Fóton Único/instrumentaçãoRESUMO
BACKGROUND: The purpose of this study was to correlate the basal cerebral blood flow (CBF) in patients with major depressive disorder (MDD) with the score for each of the 21 questions in the Hamilton Rating Scale for Depression (HRSD), in order to determine the cerebral regions associated with each item. METHODS: Fourteen antidepressant-naive patients with unipolar depression (DSM-IV criteria for MDD) participated in this study with a HRSD score of >/=20 points. CBF images obtained by SPECT were analyzed by SPM99 software. The significant correlation threshold for a priori regions (frontocortical and limbic regions) was a Z value of at least 2.25 and clusters formed by more than 10 voxels. RESULTS: Items 1, 6, 11 and 20 were positively correlated with right medial frontal gyrus; item 7 was negatively correlated with bilateral medial frontal gyrus. Items 2 and 10 were positively correlated with right anterior and medial cingulate, respectively. Item 5 was negatively correlated with the left amygdala. Item 9 was negatively correlated with bilateral insula, and item 16 with right insula. Items 12 and 14 were positively correlated with right and left precentral frontal gyrus, respectively. LIMITATIONS: The small sample size and only out-patients included in the study. CONCLUSIONS: The frontal cortex plays an important role in the expression of MDD symptoms. Not all the symptoms evaluated correlated with one single structure, which may explain the diverse results reported in the literature. These preliminary results support the necessity of further analyses by symptoms that could provide more specific information on the pathophysiology of MDD.
Assuntos
Encéfalo/irrigação sanguínea , Cisteína/análogos & derivados , Transtorno Depressivo/diagnóstico , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Adulto , Tonsila do Cerebelo/irrigação sanguínea , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiopatologia , Encéfalo/diagnóstico por imagem , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , Transtorno Depressivo/diagnóstico por imagem , Transtorno Depressivo/fisiopatologia , Feminino , Lobo Frontal/irrigação sanguínea , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiopatologia , Lateralidade Funcional/fisiologia , Giro do Cíngulo/irrigação sanguínea , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Sistema Límbico/irrigação sanguínea , Sistema Límbico/diagnóstico por imagem , Sistema Límbico/fisiopatologia , Masculino , Compostos de Organotecnécio , Fluxo Sanguíneo Regional/fisiologia , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricosRESUMO
PURPOSE: To characterize perfusion patterns of periictal single-photon emission tomography (SPECT) in patients with unilateral temporal lobe epilepsy (TLE) and to determine their relationship to the epileptogenic zone (EZ). METHODS: We studied periictal SPECT scans of 53 patients after anterior mesial temporal lobectomy who had good seizure outcome after surgery. Ictal SPECT scans were performed during video-EEG monitoring. Typical SPECT patterns consisted of ipsilateral ictal hyperperfusion or ipsilateral postictal hypoperfusion. Atypical ictal patterns included normal scans, bilateral temporal hyperperfusion, or contralateral patterns. These perfusion patterns were retrospectively analyzed searching for concordance rate with the EZ. RESULTS: We obtained 51 ictal and two early postictal scans. In the typical group, 40 (75.4%) patients had ipsilateral ictal temporal lobe hyperperfusion, and one (1.9%) patient had ipsilateral postictal temporal lobe hypoperfusion. Twelve (22.7%) patients exhibited atypical perfusion patterns: seven (13.2%) patients had bitemporal ictal hyperperfusion (four cases showed asymmetric temporal lobe changes), four (7.6%) patients had contralateral hyperperfusion, and one (1.9%) patient had a normal SPECT scan. All four patients with bitemporal asymmetric hyperperfusions showed greater perfusion lateralized to the side of the EZ. Three of the four patients who had contralateral hyperperfusion also had a complex postictal-like pattern in the ipsilateral temporal lobe consisting of anteromesial hyperperfusion with adjacent lateral hypoperfusion. CONCLUSIONS: This study analyzed typical and atypical perfusion patterns in unilateral TLE, and suggested that not only typical, but also some atypical perfusion patterns may contribute to the lateralization of EZ.
Assuntos
Epilepsia do Lobo Temporal/diagnóstico por imagem , Lateralidade Funcional/fisiologia , Lobo Temporal/irrigação sanguínea , Lobo Temporal/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Adolescente , Adulto , Eletroencefalografia/estatística & dados numéricos , Epilepsia do Lobo Temporal/diagnóstico , Epilepsia do Lobo Temporal/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/estatística & dados numéricos , Estudos Retrospectivos , Lobo Temporal/fisiopatologia , Gravação de VideoteipeRESUMO
In contrast to the other areas of functional neurosurgery, psychosurgery has remained basically empiric and unchanged since the seventies, except for the recent suggestion to use chronic stimulation instead of ablative surgery. In this study, the authors investigated the value of SPECT abnormalities to guide psychosurgery and correlated the surgical results with the postoperative SPECT. This new approach, SPECT-based tailored psychosurgery, was applied in 4 of 11 patients referred for surgery, who fulfilled the inclusion criteria adopted. Excellent results were obtained in all of them after a follow-up of 30-52 months. Postoperative SPECT normalized in every case. We conclude, based on this small series, that it is possible to individualize and lateralize (tailor) psychosurgical procedures for every patient and that, to achieve this goal, SPECT is a rather impressive means and that postoperative SPECT closely correlated with the surgical results.
Assuntos
Psicocirurgia/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Masculino , Psicocirurgia/estatística & dados numéricos , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricosRESUMO
Left ventricular (LV) function and volumes have major diagnostic and prognostic importance in patients with heart diseases. Those measurements are most commonly obtained with echocardiographic techniques. Recently, with the use of electrocardiographic gating during the acquisition of myocardial perfusion scintigraphy, it has become possible to simultaneously assess LV perfusion, function and volumes. Both technetium-99m labeled agents and thallium-201, the most commonly used tracers for perfusion scintigraphy, can be used for gated perfusion purposes. Many authors compared gated perfusion images to echocardiography, in regard to LV global and segmental wall motion as well as volumes. We performed gated single photon emission computed tomography (SPECT) and echocardiography in 109 consecutive patients (53 male, 56 female, mean age 63 +/- 14 years) within 15 days of each other. Gated tomographic data, including LV volumes, LV ejection fraction and segmental wall motion, were processed using an automatic algorithm whereas echocardiography used standard techniques. To obtain interobserver and intraobserver variability of regional wall motion, we randomly re-analyzed 34 of the 109 gated SPECT studies. The correlations between gated tomography and echocardiography with respect to end-diastolic volume, end-systolic volume and left ventricular ejection fraction were good to excellent (all p < 0.001, r values > or = 0.68) regardless of the use of post-stress or rest/redistribution images, thallium-201 or technetium-99m tracers. The agreement between both techniques, regarding segmental wall motion analysis were also good. Intraobserver and interobserver variability for regional wall motion were good to excellent, with an agreement of 90% and 88%, respectively. Other authors also had similar results in different studies with different populations, tracers, imaging acquisition and processing protocols. Thus, quantitative gated SPECT, using a variety of protocols and with either Tl-201 or Tc-99m tracers, has a good correlation with echocardiography for the measurements of absolute LV volumes and LV global and regional function. This technique is highly reproducible and can be used clinically for those measurements, with the additional advantage that the ventricular performance parameters are obtained from the perfusion images. Furthermore, contrary to echocardiographic techniques used to assess LV volumes and LV function, which are quite labor intensive and more observer-dependent, the gated SPECT technique is nearly totally automatic, and highly reproducible.
Assuntos
Ecocardiografia , Imagem do Acúmulo Cardíaco de Comporta , Tomografia Computadorizada de Emissão de Fóton Único , Função Ventricular Esquerda , Idoso , Ecocardiografia/estatística & dados numéricos , Feminino , Imagem do Acúmulo Cardíaco de Comporta/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricosRESUMO
BACKGROUND: Myocardial perfusion assessed by a pharmacological scintigraphic test is a time-honored method to assess the functional significance of a coronary stenosis. There is no study that has compared coronary flow reserve assessed by adenosine/base contrast-enhanced transthoracic echo Doppler in harmonic mode with myocardial perfusion by adenosine/base 99mTc-sestamibi SPECT. The aim of this study was to compare the absolute coronary flow reserve measured in the left anterior descending coronary artery using a new noninvasive method (transthoracic harmonic Doppler) with adenosine/base 99mTc-sestamibi SPECT. METHODS: Twenty-two patients scheduled for coronary angiography underwent evaluation of basal and hyperemic flow in the left anterior descending coronary artery using transthoracic harmonic Doppler. Simultaneously (during the same adenosine infusion) the patients were injected with 99mTc-sestamibi (10 mCi). Baseline scintigraphic study was obtained 4 hours later (99mTc-sestamibi, 30 mCi). RESULTS: Angiography showed in the left anterior descending coronary artery no or not significant stenosis (< 40% lumen narrowing) in 14 patients (Group I) and a severe stenosis (> 75%) in the remaining 8 patients (Group II). Coronary flow reserve dichotomized as normal (> or = 2.0) or abnormal (< 2.0) gave concordant results with SPECT. Overall, in fact, 18 studies (81%) were in agreement (k = 0.48, p = 0.02). In addition, coronary flow reserve proved to be a useful complementary tool to SPECT in patients with severe multivessel disease (and global hypoperfusion; 2 cases) and left bundle branch block (1 case). CONCLUSIONS: Coronary flow reserve assessed by transthoracic harmonic Doppler gives concordant results with SPECT perfusion scintigraphy. The diagnostic potential of SPECT may be increased by the noninvasive assessment of coronary flow reserve in the left anterior descending coronary artery.
Assuntos
Doença das Coronárias/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Coração/diagnóstico por imagem , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adulto , Idoso , Angiografia Coronária , Circulação Coronária , Doença das Coronárias/fisiopatologia , Vasos Coronários/fisiopatologia , Ecocardiografia Doppler em Cores/métodos , Ecocardiografia Doppler em Cores/estatística & dados numéricos , Feminino , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricosRESUMO
PURPOSE: To evaluate the accuracy, feasibility and clinical value of both ictal and interictal 99mTc-ethyl cysteinate dimer (ECD) single photon emission computed tomography (SPECT) in patients with medically refractory epilepsy. METHODS: The study included 75 consecutive patients, 48 with temporal lobe epilepsy (TLE group), and 27 with extratemporal epilepsy (ExT group). The accuracy of SPECT was analyzed considering the final diagnosis reached by convergence of clinical, electrophysiologic, structural, pathologic and outcome data. RESULTS: Ictal SPECT correctly identified the epileptogenic zone in 21 (91.3%) of 23 patients, whereas interictal SPECTs could correctly identify the epileptogenic zone in only 41 (62.1%) of 66 patients (chi2 = 5.56, df = 1, p < 0.05). Results were similar when the two study groups were analyzed separately. Moreover, ictal studies had significantly higher specificity (91.3 vs. 60.6%) and positive predictive value (91.3 vs. 66.2%) than interictal studies for the whole series of patients. Considering all tools used in the preoperative workup of these patients, ictal SPECT significantly contributed to the final topographic diagnosis in seven of 14 patients from TLE group and in six of nine patients from the ExT group. In these patients, ictal SPECT either obviated the need for invasive EEG or helped to define where to concentrate the efforts of invasive investigation. CONCLUSIONS: These data demonstrate that ictal SPECT can be easily achieved by using 99mTc-ECD and can accurately localize the epileptogenic zone in both temporal and extratemporal epilepsies. Ictal ECD SPECT proved to be significantly more sensitive and specific than interictal ECD SPECT, and clinically useful in the definition of the epileptogenic zone.
Assuntos
Córtex Cerebral/diagnóstico por imagem , Cisteína/análogos & derivados , Epilepsia/diagnóstico por imagem , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único , Algoritmos , Córtex Cerebral/fisiopatologia , Árvores de Decisões , Eletroencefalografia , Epilepsia/diagnóstico , Epilepsia/fisiopatologia , Epilepsia do Lobo Temporal/diagnóstico , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Tecnécio Tc 99m Exametazima , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricosRESUMO
Introducida hace ya dos décadas atrás, la tomografía de emisión de fotón único SPECT, ha tenido su mayor auge en éste último decenio, empleándose con éxito en la evaluación del flujo sanguíneo cerebral (FSC), ya sea en forma global como regional de sus diferentes territorios, permitiendo así una mejor comprensión, tanto de su fisiología como los cambios que allí ocurren en diferentes entidades clínicas. Esta técnica se desarrolló a partir de la experiencia adquirida en el uso de la tomografía de emisión de positrones (PET), que utiliza radiofármacos de vida media ultracorta como el oxígeno 15, carbono 11, clucosa marcada con flúor 18 entre otros, con los cuales es posible el estudio del metabolismo cerebral. Dado su alto costo y complejidad, el PET está disponible en pocos centros a nivel muldial. Estos hechos, junto con una mayor disponibilidad de gammacámaras SPECT, condujeron a producción de trazadores de flujo cerebral que se pueden marcar con emisores de fotones simples, en la base que el FSC y el metabolismo se modifican paralelamente. Mientras los métodos de diagnósticos por imágenes como la tomografía axial computada (TAC) y la resonancia nuclear magnética (RNM) nos entregan esencialmente información de carácter morfológico, el SPECT proporciona información principalmente funcional
Assuntos
Humanos , Demência , Tomografia Computadorizada de Emissão de Fóton Único , Doença de Alzheimer/diagnóstico , Cérebro/irrigação sanguínea , Diagnóstico Diferencial , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricosAssuntos
Humanos , Doença de Alzheimer , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Ecoencefalografia/estatística & dados numéricos , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada de Emissão de Fóton Único/instrumentaçãoRESUMO
Describimos el caso de una niña de 8 años de edad con epilepsia parcial continua (EPC) con sacudidas clónicas del hemicuerpo izquierdo y con deterioro neurológico progresivo. Los tratamientos antiepilépticos fracasaron en mejorar el cuadro convulsivo. La paciente fue estudiada con SPECT-99mTc-HMPAO, además de electroencefalograma (EEG), tomografía computada (TCC) y resonancia magnética de cráneo (IRM). Durante el periodo ictal, los estudios de SPECT demostraron un aumento del flujo sanguíneo cerebral en el hemisferio cerebral derecho, y durante el periodo interictal, una disminución del flujo sanguíneo en el mismo hemisferio, particularmente en lóbulo temporal y área rolándica. El EEG mostró descargas epileptógenas continuas caracterizadas por puntas y puntas onda en el hemisferio cerebral. La TCC fue normal y la IRM mostró incremento de la señal en el hemisferio cerebral derecho especialmente en región rolándica y lóbulos temporal y frontal. Se programó para lobectomía temporal y corticectomía frontal derecha. Un estudio histopatológico reveló cambios compatibles con encefalitis viral (síndrome de Rasmussen). La paciente ha continuado sin crisis convulsivasa 10 meses de seguimiento y con programa de rehabilitación intensivo. Regresó a la escuela tres meses después de la cirugía caminando con apoyo de un bastón y su IQ fue normal. Este estudio muestra la utilidad del SPECT en el diagnóstico y manejo de la EPC
Assuntos
Humanos , Feminino , Eletroencefalografia , Encefalite/diagnóstico , Epilepsia Parcial Contínua/diagnóstico , Manifestações Neurológicas , Convulsões/diagnóstico , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricosRESUMO
Se correlacionó el flujo cerebral regional (FSCr) mediante SPECT con [99m-Tc]-HM-PAO con las características clínicas más importantes en 25 pacientes con enfermedad de Parkinson idiopática (EP) y se comparó con un grupo control de 9 individuos sanos apareados en edad. Se calcularon índices de actividad relativa en 11 pares de regiones de interés (ROIs) corticales y subcorticales. Además, se determinó un índice de asimetría izquierdo-derecha para cada par de ROIs. Aunque se observaron asimetrías y déficits de la perfusión estriatal en varios pacientes, los valores medios no fueron diferentes a los del grupo control. No se encontró una relación entre el FSCr y los siguientes parámetros clínicos: lateralidad, signo predominante, tiempo de evolución y estadío de la enfermedad. Sólo se observaron diferencias estadísticamente significativas en las regiones temporales de ambos hemisferios cerebrales (p < 0,05) y asociada al deterioro cognitivo global. En 7 casos con demencia asociada (DSM-III-R) se observó una disminución bilateral significativa del FSCr de las ROIs temporales (p < 0,01 - lado izquierdo, p < 0,05 - lado derecho), frontales (p < 0,05) y parietal posterior (p < 0,05). Estos resultados sugieren que la perfusión a nivel temporal está asociada a la función cognitiva global y que la técnica de SPECT con [99m-TE]-HM-PAO es especialmente útil para apoyar, junto a criterios clínicos y neuropsicológicos, la presencia de un síndrome demencial en pacientes con EP (AU)