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1.
J Formos Med Assoc ; 119(5): 941-949, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31604648

RESUMO

BACKGROUND/PURPOSE: Nuclear imaging, including gallium scintigraphy and fluorodeoxyglucose (FDG) positron emission tomography (PET), has been widely used to identify focus of infection in fever of unknown origin. However, little is known about its role in critically ill patients, who are usually with multiple inflammatory foci and unable to tolerate long image acquisition time. This systematic review aimed to evaluate the diagnostic performance of FDG PET for suspected infection in critically ill patients. METHODS: PubMed and Embase were searched up to July 24th, 2019 to identify studies evaluating the diagnostic performance of FDG PET for finding infection focus in critically ill patients following the PRISMA guidelines. The bivariate mixed-effects model was used to pool the measure for diagnostic performance. Publication bias was evaluated by Deeks' method. RESULTS: A total of 4 studies with 87 patients were included. All the four studies evaluated FDG PET. Majority of the patients were either mechanically ventilated (76%) or shocked requiring vasopressors (61%). Test and transportation related adverse events were rare (2%). The summary sensitivity and specificity were 0.94 (95% CI, 0.79-0.99) and 0.66 (95% CI, 0.45-0.83), respectively. The AUC for summary ROC curve was 0.83. CONCLUSION: FDG PET was a very sensitive tool with acceptable specificity for detecting the origin of infection in critically ill patients. However, current available studies have limitation in evaluating safety issue. Further research should investigate both benefit and risk of doing this test for this group of vulnerable patients.

2.
Strahlenther Onkol ; 195(8): 707-718, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30610356

RESUMO

PURPOSE: We investigated whether radiologic parameters by dynamic contrast-enhanced (DCE) integrated magnetic resonance-positron-emission tomography (MR-PET) predicts tumor response to treatment and survival in non-metastatic non-small-cell lung cancer (NSCLC) patients receiving chemoradiotherapy (CRT). METHODS: Patients underwent DCE integrated MR-PET imaging 1 week before CRT. The following parameters were analyzed: primary tumor size, gross tumor volume, maximal standardized uptake value (SUVmax), total lesion glycolysis (TLG), apparent diffusion coefficient (ADC), volume transfer constant (Ktrans), reverse reflux rate constant (kep), extracellular extravascular volume fraction (ve), blood plasma volume fraction (vp), and initial area under the time-concentration curve defined over the first 60 s post-enhancement (iAUC60). CRT responses were defined using the revised Response Evaluation Criteria in Solid Tumors (RECIST) guideline (version 1.1). RESULTS: Thirty patients were included. Non-responders demonstrated higher baseline TLG (p = 0.012), and lower baseline Ktrans (p = 0.020) and iAUC60 (p = 0.016) compared to responders, indicating the usefulness of DCE integrated MR-PET to predict treatment responses. Receiver operating characteristic curve indicated that TLG has the best differentiation capability to predict responders. By setting the threshold of TLG to 277, the sensitivity, specificity, and accuracy were 66.7%, 83.3%, and 75.0%, respectively, with an area under the curve of 0.776. The median follow-up time was 19.6 (range 7.8-32.0) months. In univariate analyses, baseline TLG >277 (p = 0.005) and baseline Ktrans <254 (10-3 min-1; p = 0.015) correlated with poor survival after CRT. In multivariate analysis, baseline TLG >277 remained the significant factor in predicting progression (p = 0.012) and death (p = 0.031). CONCLUSIONS: The radiologic parameters derived from DCE integrated MR-PET scans are useful for predicting treatment response in NSCLC patients treated with CRT; furthermore, these parameters are correlated with clinical and survival outcomes including tumor progression and death.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/terapia , Quimiorradioterapia/métodos , Aumento da Imagem , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/terapia , Imagem por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Meios de Contraste , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/efeitos da radiação
3.
J Nucl Cardiol ; 26(5): 1584-1595, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-29484543

RESUMO

BACKGROUND: The benefits of attenuation correction (AC) in technetium-99m myocardial perfusion imaging (MPI) have been well established. However, the value of thallium (Tl-201) AC and routine computed tomography AC (CTAC) were less well established. The aims of this study were to evaluate the diagnostic performance of thallium (Tl-201) MPI with additional CTAC and to determine which participants would benefit most. METHODS AND RESULTS: A total of 108 consecutive patients who underwent Tl-201 MPI and received coronary angiography within 3 months were enrolled. Diagnostic performance was determined by sensitivity, specificity, and receiver operating characteristic curve analysis. Subgroup analyses were performed using gender and obesity. CTAC improved the area under the curve (0.84 vs. 0.77, P = 0.037 at patient level), primarily due to a significant improvement in specificity (0.78 vs. 0.57, P = 0.013) and no significant difference in sensitivity (0.79 vs. 0.82, P = 0.75). In subgroup analysis, CTAC was most helpful in obese subjects, men, and especially right coronary artery lesions. CONCLUSIONS: CTAC significantly improved diagnostic performance primarily by increasing the specificity, and the improvements were significantly greater in obese patients and male patients. These findings suggest that CTAC should be applied to Tl-201 MPI as routine clinical practice.

4.
J Magn Reson Imaging ; 47(1): 191-199, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28480541

RESUMO

PURPOSE: To evaluate the response in patients undergoing SBRT using dynamic contrast-enhanced (DCE) integrated magnetic resonance positron emission tomography (MR-PET). Stereotactic body radiation therapy (SBRT) is efficacious as a front-line local treatment for non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: We prospectively enrolled 19 lung tumors in 17 nonmetastatic NSCLC patients who were receiving SBRT as a primary treatment. They underwent DCE-integrated 3T MR-PET before and 6 weeks after SBRT. The following image parameters were analyzed: tumor size, standardized uptake value (SUV), apparent diffusion coefficient, Ktrans , kep , ve , vp , and iAUC60 . Chest computed tomography (CT) was performed at 3 months after SBRT. RESULTS: SBRT treatment led to tumor changes including significant decreases in the SUVmax (-61%, P < 0.001), Ktrans mean (-72%, P = 0.005), Ktrans standard deviation (SD; -85%, P = 0.046), kep mean (-53%, P = 0.014), kep SD (-63%, P = 0.001), and vp SD (-58%, P = 0.002). The PET SUVmax was correlated with the MR kep mean (P = 0.002) and kep SD (P < 0.001). The percentage reduction in Ktrans mean (P < 0.001) and kep mean (P = 0.034) at 6 weeks post-SBRT were significantly correlated with the percentage reduction in tumor size, as measured using CT at 3 months after SBRT. Univariate analyses revealed a trend toward disease progression when the initial SUVmax > 10 (P = 0.083). CONCLUSION: In patients with NSCLC who are receiving SBRT, DCE-integrated MR-PET can be used to evaluate the response after SBRT and to predict the local treatment outcome. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:191-199.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Imagem por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Radiocirurgia , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Meios de Contraste/química , Progressão da Doença , Intervalo Livre de Doença , Feminino , Fluordesoxiglucose F18/química , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Estudos Prospectivos , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
5.
J Nucl Med ; 57(12): 1893-1898, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27445295

RESUMO

Myocardial perfusion imaging (MPI) with SPECT is a well-established tool for the diagnosis of coronary artery disease (CAD). However, soft-tissue attenuation is a common artifact that limits the diagnostic accuracy of MPI. The aim of this study was to determine whether attenuation correction (AC) improved the diagnostic performance of MPI, using coronary angiography as a reference standard. METHODS: MEDLINE and EMBASE were searched until March 2015 for studies evaluating AC MPI for the diagnosis of CAD. Methodologic quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool. For each study, the sensitivity, specificity, and diagnostic odds ratio, along with 95% confidence intervals (CIs), were calculated to determine the diagnostic accuracy of AC versus non-attenuation-corrected (NAC) MPI. A bivariate mixed-effects model was applied for pooling the data. RESULTS: Of 201 articles, 17 studies (1,701 patients) were identified, including 5 studies that used CT AC, 12 studies that used radionuclide source AC (RAC), and 15 studies that reported NAC results. The pooled sensitivities across studies were 0.80 (95% CI, 0.64-0.91), 0.85 (95% CI, 0.81-0.88), 0.84 (95% CI, 0.79-0.88), and 0.80 (95% CI, 0.75-0.85) for CT AC, RAC, all AC, and NAC, respectively. The pooled specificities were 0.83 (95% CI, 0.71-0.91), 0.81 (95% CI, 0.73-0.86), 0.80 (95% CI, 0.74-0.85), and 0.68 (95% CI, 0.61-0.74). Both sensitivities and specificities resulted in a pooled diagnostic odds ratio of 20 (95% CI, 12-34), 24 (95% CI, 13-43), 22 (95% CI, 13-35), and 9 (7-11). Significant differences in specificity and diagnostic odds ratios were noted when AC (including CT AC, RAC, and all AC) was compared with NAC. CONCLUSION: The results from this study suggested that AC should be applied to MPI to improve the diagnosis of CAD, especially the specificity.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Imagem de Perfusão do Miocárdio/métodos , Humanos , Processamento de Imagem Assistida por Computador , Sensibilidade e Especificidade
6.
Pediatr Crit Care Med ; 17(2): e58-65, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26649939

RESUMO

OBJECTIVES: PET/CT with F-fluorodeoxyglucose can be used to image cellular metabolism and has been used for evaluating fever of unknown origin in adults. However, there are limited studies about the role of F-fluorodeoxyglucose PET/CT in evaluation of fever of unknown origin in critically ill children, especially those presenting with complicated underlying diseases under treatment. Here, we report our preliminary experience using F-fluorodeoxyglucose PET/CT in this specific group of patients. DESIGN: Retrospective observational study. SETTING: PICUs of a university hospital. PATIENTS: Nineteen critically ill children (mean age, 5.7 yr old) with complicated underlying diseases requiring intensive care support underwent F-fluorodeoxyglucose PET/CT to evaluate fever of unknown origin. The median hospitalized stay was 34 days (range, 15-235 d) and fever of at least 7 days (mean, 21.6 d; range, 7-52 d). The PET scan was advocated after all routine microbiology, and conventional imaging showed negative or inconclusive results. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The F-fluorodeoxyglucose PET/CT findings (blinded to the final clinical diagnosis) were compared with final histopathology, culture, serology results, or follow-up imaging. A final diagnosis was made in 16 patients (84.2%). F-fluorodeoxyglucose PET/CT accurately localized the source of fever in 14 patients, confers to a sensitivity of 87.5% (14 of 16; 95% CI, 0.604-0.978). A false-positive scan in a patient led to subsequent unnecessary investigations. Two false-negative F-fluorodeoxyglucose PET/CT images were later attributed to relapse of underlying disease in the bone marrow and renal abscesses, respectively. In the other two patients where F-fluorodeoxyglucose PET/CT also showed negative findings, fever subsided shortly thereafter without treatment. CONCLUSIONS: Our preliminary experience suggests that F-fluorodeoxyglucose PET/CT may be clinically beneficial in evaluating fever of unknown origin in children with complicated underlying diseases mandating intensive support in ICUs if usual investigative methods are unsuccessful. Further large prospective studies are needed to validate these findings.


Assuntos
Estado Terminal , Febre de Causa Desconhecida/diagnóstico por imagem , Fluordesoxiglucose F18/administração & dosagem , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Adolescente , Criança , Pré-Escolar , Comorbidade , Diagnóstico Diferencial , Feminino , Febre de Causa Desconhecida/complicações , Hospitais Universitários , Humanos , Lactente , Unidades de Terapia Intensiva Pediátrica , Tempo de Internação , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade
7.
PLoS One ; 9(5): e97710, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24842767

RESUMO

OBJECTIVE: Coronary artery disease (CAD) is associated with abdominal obesity and metabolic syndrome. Adipocytes secrete adipokines, including the newly discovered adipocyte fatty acid binding protein (A-FABP) and chemerin. Adipokines contribute to the pathogenesis of CAD. In patients with CAD, the presence of significant ischemia predicts adverse outcomes. It is unknown whether adipokines can be better predictors of the presence of significant myocardial ischemia than conventional risk factors. This study aimed to compare adipokines with clinical risk factors and abdominal obesity as predictive factors for significant myocardial ischemia. METHODS: One hundred and ninety-six adults with suspected, but unproven, CAD were consecutively enrolled. The main measures were clinical and biochemical parameters and stress myocardial perfusion imaging with gated myocardial perfusion single-photon emission computed tomography (SPECT), with computed tomography (CT) attenuation correction. The abdominal visceral fat area was examined using a hybrid SPECT/CT scanner. Serum levels of high-sensitivity C-reactive protein (hs-CRP) and adipokines (adiponectin, A-FABP, and chemerin) were evaluated. RESULTS: A-FABP levels correlated significantly with adiponectin, hs-CRP, body mass index, waist circumference, and visceral fat area. A-FABP was significantly associated with metabolic syndrome (OR 3.2, 95% CI 1.6-6.4, p = 0.001), significant myocardial ischemia (OR 1.9, 95% CI 1.0-3.4, p = 0.05), and stress lung-to-heart ratio (ß = 0.03, p = 0.03) on SPECT. Chemerin was significantly associated with serum triglyceride levels but not with metabolic syndrome, significant ischemia, or stress lung-to-heart ratio on SPECT. A-FABP was better at detecting significant inducible ischemia than other biomarkers, although this was a modest improvement (area under ROC curve 0.579, 95% CI 0.46-0.69). CONCLUSIONS: Serum A-FABP concentrations correlate significantly with visceral fat area, metabolic syndrome, and predicted significant myocardial ischemia on SPECT. This may help to more accurately assess CAD risk, especially in patients with metabolic syndrome.


Assuntos
Adipocinas/sangue , Isquemia Miocárdica/diagnóstico , Obesidade Abdominal/patologia , Adiponectina/sangue , Área Sob a Curva , Índice de Massa Corporal , Proteínas de Ligação a Ácido Graxo/sangue , Humanos , Isquemia Miocárdica/sangue , Isquemia Miocárdica/etiologia , Obesidade Abdominal/complicações , Razão de Chances , Curva ROC , Fatores de Risco , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Circunferência da Cintura
8.
J Formos Med Assoc ; 110(8): 537-42, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21783023

RESUMO

Niemann-Pick type C disease (NPC) is a rare autosomal recessive lipid storage disorder caused by impaired cellular functions in processing and transporting low-density lipoprotein-cholesterol. In this report, we present magnetic resonance imaging (MRI), magnetic resonance spectrography (MRS) and 18-fluoro-2-deoxyglucose positron emission tomography (PET) imaging results for a 22-year-old male NPC patient. The patient's two MRI studies (at age 19 years and 22 years) demonstrated progressive changes of brain atrophy that were more prominent at the frontal lobes, and hyperintense signals in bilateral parietal-occipital periventricular white matter. MRS (at age 19 years) revealed no significant decrease in N-acetyl aspartate/choline ratio in the left frontal central white matter. PET (at age 22 years) showed significant bilateral hypometabolism in the prefrontal cortex and dorsomedial thalamus, and hypermetabolism in the parietal-occipital white matter, lenticular nucleus of the basal ganglia, cerebellum and pons. The imaging findings noted by MRI, MRS and 18-fluoro-2-deoxyglucose PET offered a possible supplementary explanation for the clinical neurological symptoms of this NPC patient.


Assuntos
Imagem por Ressonância Magnética , Doença de Niemann-Pick Tipo C/diagnóstico , Diagnóstico Diferencial , Progressão da Doença , Gastrostomia , Humanos , Masculino , Exame Neurológico , Adulto Jovem
10.
Clin Nucl Med ; 36(3): 258-60, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21285696

RESUMO

An 80-year-old woman, who had suffered from end-stage renal disease under peritoneal dialysis, was presented with intermittent fever, leukocytosis, and elevated C-reactive protein for 4 months. She did not have symptom of abdominal pain. Culture of ascites showed Klebsiella pneumoniae. Abdominal utrasonography was negative. Whole-body gallium-67 imaging showed a segmental uptake mimicking bowels in right abdomen. SPECT/CT revealed the uptake in a soft tissue density beneath the abdominal wall instead of bowels. Contrast-enhanced CT demonstrated a low-density mass with peripheral enhancement at the aforementioned area. Her clinical condition stabilized gradually after CT-guided percutaneous drainage of pus from the abscess.


Assuntos
Abscesso Abdominal/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Idoso de 80 Anos ou mais , Feminino , Radioisótopos de Gálio , Humanos , Imagem Corporal Total
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