Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Eur J Nucl Med Mol Imaging ; 48(12): 3925-3939, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33851243

RESUMO

PURPOSE: The objective of this review was to explore the potential clinical application of unconventional non-amino acid PET radiopharmaceuticals in patients with gliomas. METHODS: A comprehensive search strategy was used based on SCOPUS and PubMed databases using the following string: ("perfusion" OR "angiogenesis" OR "hypoxia" OR "neuroinflammation" OR proliferation OR invasiveness) AND ("brain tumor" OR "glioma") AND ("Positron Emission Tomography" OR PET). From all studies published in English, the most relevant articles were selected for this review, evaluating the mostly used PET radiopharmaceuticals in research centers, beyond amino acid radiotracers and 2-[18F]fluoro-2-deoxy-D-glucose ([18F]FDG), for the assessment of different biological features, such as perfusion, angiogenesis, hypoxia, neuroinflammation, cell proliferation, tumor invasiveness, and other biological characteristics in patients with glioma. RESULTS: At present, the use of non-amino acid PET radiopharmaceuticals specifically designed to assess perfusion, angiogenesis, hypoxia, neuroinflammation, cell proliferation, tumor invasiveness, and other biological features in glioma is still limited. CONCLUSION: The use of investigational PET radiopharmaceuticals should be further explored considering their promising potential and studies specifically designed to validate these preliminary findings are needed. In the clinical scenario, advancements in the development of new PET radiopharmaceuticals and new imaging technologies (e.g., PET/MR and the application of the artificial intelligence to medical images) might contribute to improve the clinical translation of these novel radiotracers in the assessment of gliomas.


Assuntos
Neoplasias Encefálicas , Glioma , Inteligência Artificial , Neoplasias Encefálicas/diagnóstico por imagem , Fluordesoxiglucose F18 , Glioma/diagnóstico por imagem , Humanos , Imagem Molecular , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X
3.
J Nucl Cardiol ; 24(3): 876-887, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-26911365

RESUMO

BACKGROUND: The introduction of a camera-based dose-reduction strategy in myocardial perfusion imaging (MPI) clinical setting entails the definition of objective and reproducible criteria for establishing the amount of activity to be injected. AIM: The aim is to evaluate the impact of count statistics on the estimation of summed-scores (SS), end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF). METHODS: Data rest/stress ECG-gated SPECT (2-day protocol and 8 MBq·kg-1) were acquired with Bright View gamma camera and Astonish algorithm for 40 normal-weight and 40 overweight patients. Assuming that count statistics of shorter acquisition time may simulate that of lower injected activity, three simultaneous scans (full-time, half-time, and quarter-time scans) were started at the same time but with different acquisition time/projection (30, 15 and 8 seconds). RESULTS: A significant difference between SS values of half-time and quarter-time stress scans was found for overweight group (P = .006). Post hoc test showed significant differences for ESV (P < .05), EDV (P < .01) and EF (P < .05) between half-time and quarter-time scans for both patient groups. CONCLUSIONS: The reduction of the count-statistics to a quarter of the MPI reference influenced negatively the quantification in overweight patients. The decrease of radiopharmaceutical activity to 25% of the reference seems practicable for normal-weight patients, while it is more appropriate an activity reduction limited to 50% for overweight and obese patients.


Assuntos
Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Obesidade/diagnóstico por imagem , Compostos Organofosforados/administração & dosagem , Compostos de Organotecnécio/administração & dosagem , Exposição à Radiação/análise , Exposição à Radiação/prevenção & controle , Idoso , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Imagem de Perfusão do Miocárdio , Proteção Radiológica/métodos , Compostos Radiofarmacêuticos/administração & dosagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Volume Sistólico
4.
Eur J Nucl Med Mol Imaging ; 43(2): 340-348, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26250689

RESUMO

PURPOSE: The aim of this study was to analyse if the result of a baseline (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT scan, in large-vessel vasculitis (LVV) patients, is able to predict the course of the disease, not only in terms of presence/absence of final complications but also in terms of favourable/complicated progress (response to steroid therapy, time to steroid suspension, relapses, etc.). METHODS: A total of 46 consecutive patients, who underwent (18)F-FDG PET/CT between May 2010 and March 2013 for fever of unknown origin (FUO) or suspected vasculitis (before starting corticosteroid therapy), were enrolled. The diagnosis of LVV was confirmed in 17 patients. Considering follow-up results, positive LVV patients were divided into two groups, one characterized by favourable (nine) and the other by complicated progress (eight), on the basis of presence/absence of vascular complications, presence/absence of at least another positive PET/CT during follow-up and impossibility to comply with the tapering schedule of the steroid due to biochemical/symptomatic relapse. Vessel uptake in subjects of the two groups was compared in terms of intensity and extension. To evaluate the extent of active disease, we introduced two volume-based parameters: "volume of increased uptake" (VIU) and "total lesion glycolysis" (TLG). The threshold used to calculate VIU on vessel walls was obtained by the "vessel to liver" ratio by means of receiver-operating characteristic analysis and was set at 0.92 × liver maximum standardized uptake value in each patient. RESULTS: Measures of tracer uptake intensity were significantly higher in patients with complicated progress compared to those with a favourable one (p < 0.05). Measures of disease extension were even more significant and TLG emerged as the best parameter to separate the two groups of patients (p = 0.01). CONCLUSION: This pilot study shows that, in LVV patients, the combined evaluation of the intensity and the extension of FDG vessel uptake at diagnosis can predict the clinical course of the disease, separating patients with favourable or complicated progress.


Assuntos
Arterite/diagnóstico por imagem , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Corticosteroides/administração & dosagem , Idoso , Arterite/tratamento farmacológico , Arterite/patologia , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos
5.
HIV Med ; 16(9): 563-71, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25944496

RESUMO

OBJECTIVES: The aim of this study was to evaluate the clinical impact of including lateral spine X-ray in the screening of bone diseases in HIV-positive patients. METHODS: A total of 194 HIV-positive patients underwent dual-energy X-ray absorptiometry (DEXA), lateral spine X-ray and bone biochemical analysis. Vertebral fractures were identified using a morphometric analysis of X-rays and classified using the semiquantitative scoring system of Genant et al. For each patient, a spine deformity index (SDI) score was calculated by summing the grades of vertebral deformities. Reductions in vertebral body height of > 25% were considered vertebral fractures, and those < 25% were considered vertebral deformities. Risk factors associated with vertebral fractures were evaluated by univariate and multivariate analysis. RESULTS: Vertebral fractures were detected in 24 patients (12.4%) and vertebral deformities in 17 patients (8.7%); 153 patients (78.9%) did not show any vertebral deformity. Among patients with fractures, only two with SDI > 10 reported lumbar pain; the remaining were asymptomatic. Patients over 50 years old showed a higher prevalence of vertebral fracture [24.4% versus 11.8% in patients 41-50 years old (P = 0.05) and 1.9% in patients ≤ 40 years old (P = 0.04)]. No significant increase in the prevalence according to bone mineral density (BMD) reduction was observed, and 70% of fractures were diagnosed in nonosteoporotic patients. Older age [adjusted odds ratio 1.09; 95% confidence interval (CI) 1.03-1.13; P = 0.001] and steroid use (adjusted odds ratio 3.64; 95% CI 1.29-10.3; P = 0.01) were independently associated with vertebral fracture; no association was found with HIV- or highly active antiretroviral therapy (HAART)-related variables. CONCLUSIONS: A prevalence of vertebral fractures of 12.4% was observed in our HIV-positive cohort. Given that two-thirds of fractures occurred in nonosteoporotic patients, spine X-ray may be considered in patients at increased risk, irrespective of BMD; that is, in elderly patients and/or patients using steroids.


Assuntos
Infecções por HIV/complicações , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/epidemiologia , Absorciometria de Fóton/métodos , Adulto , Densidade Óssea , Feminino , Infecções por HIV/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
7.
Artigo em Inglês | MEDLINE | ID: mdl-20585311

RESUMO

AIM: Several lines of evidence indicate that the dopaminergic system may play a role in the propagation of epileptic seizures and, indeed, DOPA metabolism impairment has recently been demonstrated in PET studies of ring chromosome 20 [r(20)] patients. We conducted a study looking for correlations between r(20) mosaicism, other clinical variables and both pre-synaptic dopamine transporter (DAT) expression and post-synaptic D2 receptor density. METHODS: Five patients with r(20) and epilepsy were enrolled in the study. DAT expression and D2 density were measured by single photon emission tomography (SPECT) imaging with 185 MBq of [123I]ioflupane and [123I]IBZM, respectively, on different days. Linear correlations between r(20) mosaicism, clinical variables and binding of [123I]ioflupane or [123I]IBZM were examined. RESULTS: A significant correlation between seizure frequency and r(20) mosaicism was detected (r=0.903, P<0.05), along with a negative correlation between r(20) mosaicism and binding of [123I]ioflupane in the putamen and in the caudate nucleus (r=-0.692 and r=-807; P<0.05). Seizure frequency was positively correlated with post-synaptic D2 density (r=0.925, P<0.05). CONCLUSION: Striatal neurons are involved in r(20) epilepsy; the relationship found between r(20) mosaicism and DAT expression suggests that drugs acting on the dopaminergic system could have a place in the treatment of this rare form of epilepsy.

8.
Cardiovasc Intervent Radiol ; 42(11): 1644-1648, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31218410

RESUMO

PURPOSE: The aim of this study is to evaluate the feasibility of percutaneous lung tumor biopsy under cone beam-computed tomography (CBCT) with PET-CT imaging fusion. MATERIALS AND METHODS: Eleven patients (four women and seven men) underwent C-arm CBCT lung biopsy with PET-CT fusion imaging. A preprocedural PET-CT scan was manually fused with procedural CBCT based on anatomical landmarks; using real-time fluoroscopy, the coregistered PET-CT and CBCT images were overlaid to guide the needle trajectory. Technical success, accuracy, sensibility and specificity were evaluated. Mean total procedure time and time required for image elaboration were recorded. RESULTS: Technical success, diagnostic accuracy, sensitivity and specificity were 100%. The mean procedure time was 38 min. The average time of PET-CT/CBCT image fusion elaboration was 3.53 min for planning and 3.42 min for needle positioning check. CONCLUSION: CBCT-guided percutaneous lung biopsy with PET-CT fusion imaging is a feasible and effective procedure, with the potential to further improve diagnostic yield by targeting the most metabolically active portion of a lesion, whether it is morphologically altered or normal.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Radiografia Intervencionista/métodos , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Biópsia Guiada por Imagem/métodos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Med Oncol ; 34(10): 174, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28875374

RESUMO

The aim of this study was to evaluate the efficacy and the safety of Y90 radioembolization (Y90-RE) in patients with unresectable hepatocellular carcinoma (HCC) analysing our results and correlating them with independent prognostic factors for overall survival (OS) and for complications. Forty-three patients with advanced inoperable HCC including those with multiple bilobar lesions or portal vein thrombosis (PVT) treated with Y90-RE were reviewed. Treatment efficacy and safety were evaluated. Survival was calculated by the Kaplan-Meier method. Univariate analyses were performed for identifying potential prognostic factors. Radiologic response was evaluated with the modified Response Evaluation Criteria in Solid Tumours (mRECIST) criteria. Clinical toxicities were prospectively recorded. Median overall progression-free survival and OS were 27.7 and 16.8 months, respectively. Longer median OS was revealed in those without PVT (p = 0.0241) and those whose pre-treatment haemoglobin values was higher (p = 0.0471). According with mRECIST criteria, we observed a disease control rate of 69.2 and 61.9% at 3- and 6-month follow-up, respectively. Complications developed in 28 patients (65.1%), among which grade 2-3 events were reported in 17 patients. We noted that activity administered dose presented a correlation with intra-procedural toxicity (p = 0.039259) while common hepatic artery use as release site was associated with a most frequent presentation of remote adverse events. Y90-RE is an alternative treatment with a promising outcome for poor-risk advanced inoperable HCC. PVT and pre-treatment haemoglobin values can be predictors of efficacy. Activity administered dose and arterial release site can be predictors of safety.


Assuntos
Carcinoma Hepatocelular/terapia , Embolização Terapêutica/métodos , Neoplasias Hepáticas/terapia , Idoso , Carcinoma Hepatocelular/mortalidade , Intervalo Livre de Doença , Embolização Terapêutica/efeitos adversos , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Compostos Radiofarmacêuticos , Resultado do Tratamento , Radioisótopos de Ítrio
11.
Funct Neurol ; 31(4): 205-215, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28072381

RESUMO

Neuroimaging, both with magnetic resonance imaging (MRI) and positron emission tomography (PET), has gained a pivotal role in the diagnosis of primary neurodegenerative diseases. These two techniques are used as biomarkers of both pathology and progression of Alzheimer's disease (AD) and to differentiate AD from other neurodegenerative diseases. MRI is able to identify structural changes including patterns of atrophy characterizing neurodegenerative diseases, and to distinguish these from other causes of cognitive impairment, e.g. infarcts, space-occupying lesions and hydrocephalus. PET is widely used to identify regional patterns of glucose utilization, since distinct patterns of distribution of cerebral glucose metabolism are related to different subtypes of neurodegenerative dementia. The use of PET in mild cognitive impairment, though controversial, is deemed helpful for predicting conversion to dementia and the dementia clinical subtype. Recently, new radiopharmaceuticals for the in vivo imaging of amyloid burden have been licensed and more tracers are being developed for the assessment of tauopathies and inflammatory processes, which may underlie the onset of the amyloid cascade. At present, the cerebral amyloid burden, imaged with PET, may help to exclude the presence of AD as well as forecast its possible onset. Finally PET imaging may be particularly useful in ongoing clinical trials for the development of dementia treatments. In the near future, the use of the above methods, in accordance with specific guidelines, along with the use of effective treatments will likely lead to more timely and successful treatment of neurodegenerative dementias.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Demência/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Doenças Neurodegenerativas/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Encéfalo/patologia , Encéfalo/fisiopatologia , Demência/complicações , Demência/patologia , Humanos , Doenças Neurodegenerativas/complicações , Doenças Neurodegenerativas/patologia
12.
Clin Transl Imaging ; 4(6): 491-498, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27933282

RESUMO

PURPOSE: Over the past decade, nuclear medicine experts have been seeking to minimize patient exposure to radiation in myocardial perfusion scintigraphy (MPS). This review describes the latest technological innovations in MPS, particularly with regard to dose reduction. METHODS: We searched in PubMed for original clinical papers in English, published after 2008, using the following research criteria: (dose) and ((reduction) or (reducing)) and ((myocardial) or (cardiac) or (heart)) and ((nuclear medicine) or (nuclear imaging) or (radionuclide) or (scintigraphy) or (SPET) or (SPECT)). Thereafter, recent reviews on the topic were considered and other relevant clinical papers were added to the results. RESULTS: Of 202 non-duplicate articles, 17 were included. To these, another eight papers cited in recent reviews were added. By optimizing the features of software, i.e., through algorithms for iterative reconstruction with resolution recovery (IRRs), and hardware, i.e., scanners and collimators, and by preferring, unless otherwise indicated, the use of stress-first imaging protocols, it has become possible to reduce the effective dose by at least 50% in stress/rest protocols, and by up to 89% in patients undergoing a diagnostic stress-only study with new technology. With today's SPECT/CT systems, the use of a stress-first protocol can conveniently be performed, resulting in an overall dose reduction of about 35% if two-thirds of stress-first examinations were considered definitively normal. CONCLUSION: Using innovative gamma cameras, collimators and software, as well as, unless otherwise indicated, stress-first imaging protocols, it has become possible to reduce significantly the effective dose in a high percentage of patients, even when X-ray CT scanning is performed for attenuation correction.

13.
Am J Psychiatry ; 152(6): 876-82, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7755117

RESUMO

OBJECTIVE: The purpose of the study was to compare regional cerebral blood flow (CBF) in schizophrenic patients never treated with psychotropic drugs (drug-naive) and in schizophrenic patients free from drugs for various amounts of time. METHOD: Seventeen schizophrenic patients (nine who were drug naive and eight who had been drug free for at least 3 weeks) and 12 healthy volunteers were included in the study. Regional cerebral perfusion was studied with the use of a head-dedicated, high-resolution single photon emission computed tomography (SPECT) system. Cerebral SPECT scans were performed with technetium-99m-hexamethyl-propyleneamine oxime as a tracer. Regional CBF was measured as a ratio of regional tracer uptake to either cerebellar or whole brain tracer uptake. RESULTS: When the cerebellum was taken as the reference region, the drug-naive patients showed a significant bilateral reduction of perfusion in the mesial, dorsolateral, and basal prefrontal cortex, in the temporal cortex, and in the subcortical gray structures: thalamus, caudate nucleus, and putamen/pallidum complex. No significant differences emerged in the comparison between the drug-free patients and the healthy subjects. With correction for whole brain activity, some of the differences that had been found disappeared, but a significant hypoperfusion persisted in the basal ganglia and thalamus of the drug-naive, but not the drug-free, patients. Few correlations between symptom presentation and regional CBF perfusion were observed in the schizophrenic patients. CONCLUSIONS: These results suggest a pattern of cerebral hypoperfusion in schizophrenic patients never treated with neuroleptics that was not detectable in patients who had undergone various periods of pharmacological washout.


Assuntos
Antipsicóticos/uso terapêutico , Encéfalo/irrigação sanguínea , Esquizofrenia/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Adolescente , Adulto , Idade de Início , Gânglios da Base/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Cerebelo/irrigação sanguínea , Feminino , Lobo Frontal/irrigação sanguínea , Humanos , Masculino , Pessoa de Meia-Idade , Lobo Occipital/irrigação sanguínea , Compostos de Organotecnécio , Oximas , Lobo Parietal/irrigação sanguínea , Esquizofrenia/diagnóstico , Esquizofrenia/tratamento farmacológico , Tecnécio Tc 99m Exametazima , Lobo Temporal/irrigação sanguínea , Tálamo/irrigação sanguínea
14.
J Nucl Med ; 35(2): 210-6, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8294987

RESUMO

UNLABELLED: SPECT studies of regional cerebral perfusion with a high-resolution system were compared to PET studies of regional cerebral glucose utilization (rCMRglc) in 21 patients with probable Alzheimer's disease (AD). Ten normal subjects were also evaluated with SPECT and 10 with PET. METHODS: rCMRglc (for PET) and counts (for SPECT) in the associative cortices were normalized to the average rCMRglc, and counts in the calcarine cortex and basal ganglia were considered as a "reference area" to obtain a ratio. The ratio differences between patients and controls were tested with ANOVA performed separately for PET and SPECT. RESULTS: The difference between probable AD patients and controls was significant for both PET (p < 0.00001) and SPECT (p < 0.005); this difference was significant for the frontal, temporal and parietal cortices (p < 0.0001) for PET, and for the temporal (p < 0.005) and parietal (p < 0.001) cortices for SPECT. Temporo-parietal defects were detected in all subjects with PET and in 90% with SPECT. CONCLUSION: PET and SPECT are able to detect characteristic temporo-parietal abnormalities in probable AD. However, the presence of abnormalities in other associative areas is better evaluated with PET.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Desoxiglucose/análogos & derivados , Compostos de Organotecnécio , Oximas , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada de Emissão , Adulto , Idoso , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Tecnécio Tc 99m Exametazima
15.
Nuklearmedizin ; 38(5): 169-71, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10488486

RESUMO

A 66-year-old man affected by polyostotic form of fibrous dysplasia in consequence of worsening of lower extremity bone pain aggravated by walking and concomitant increase of serum alkaline phosphatase and osteocalcin, was subjected first to a radionuclide study. Bone scan demonstrated a pathological uptake of the radiotracer in the craniofacial bones, right scapula, left and right posterior ribs, right hemipelvis and lower extremities confirming the diagnosis but establishing especially the extent of bone involvement, greater than expected on the basis of symptoms and X-ray findings, underlying the importance of nuclear medicine imaging in the assessment and follow-up of this rare disease.


Assuntos
Osso e Ossos/diagnóstico por imagem , Displasia Fibrosa Poliostótica/diagnóstico por imagem , Compostos Radiofarmacêuticos , Medronato de Tecnécio Tc 99m , Idoso , Diagnóstico Diferencial , Humanos , Masculino , Radiografia , Cintilografia
16.
Nucl Med Commun ; 15(5): 311-6, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8047316

RESUMO

The relationship between severity of coronary artery stenosis (CAS) and myocardial 18F-2-fluoro-2-deoxy-D-glucose (18F-FDG) uptake in the fasting state, assessed with positron emission tomography (PET), was examined in a series of 48 patients with CAS undergoing both studies for diagnostic purposes. The data analysis was based on the subdivision of the left ventricular myocardium into four segments defined in relation to ventricular vascularization: the anterior and septal segments, perfused by the left anterior descending artery; the lateral segment, perfused by the left circumflex; and the inferior segment, perfused by the right coronary artery. The 192 segments were grouped according to degree of CAS: I 0-50%, II 51-75%; III 76-90%; IV 91-99%; V and VI occluded coronary artery with good or poor collaterals, respectively. An 18F-FDG index was determined as the tissue/blood pool radioactivity ratio in each segment. The statistical analysis was performed by one-way ANOVA, multiple comparison tests and the chi-squared test. The proportion of segments with 18F-FDG uptake was also analysed for a linear trend across the ordered levels of CAS. The 18F-FDG index in groups I to V was significantly higher than in controls, but it was not different among the groups with CAS, except for group V versus I. However, the proportion of segments with enhanced 18F-FDG uptake was correlated to the degree of CAS. In cases of complete occlusion of a major afferent coronary artery, the proportion of segments with 18F-FDG uptake varied in relation to the presence of collaterals.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Desoxiglucose/análogos & derivados , Radioisótopos de Flúor , Coração/diagnóstico por imagem , Tomografia Computadorizada de Emissão , Circulação Colateral/fisiologia , Circulação Coronária/fisiologia , Doença das Coronárias/epidemiologia , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo
17.
Nucl Med Commun ; 22(4): 399-404, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11338050

RESUMO

The aim of this study was to assess, by positron emission tomography (PET), the effect on cerebral functional activity of a new lorazepam-gamma-aminobutyric acid (GABA) conjugate [3-(4-acetamido)-butyrril lorazepam (DDS2700)]. Ten healthy volunteers were studied by PET and [18F]fluoro-deoxy-D-glucose ([18F]FDG) under baseline conditions and following the administration of DDS2700. Regional cerebral blood flow (rCBF) was measured by PET and 15O-water in three additional participants while they performed attentive tasks, before and after drug administration. DDS2700 induced a decrease in the regional cerebral metabolic rate of glucose (rCMRglu) in the thalamus (-17%), cerebellum (-11%) and caudate nucleus (-8%). The observed effects on glucose metabolism were probably related to the subjective sedation and tiredness reported by the participants. During the attentive tasks, rCBF increased in frontal and temporal regions associated with attentional processing of auditory material. These circuits were no longer active after DDS2700 administration, while rCBF increased in cingulate cortex, occipitoparietal regions, pons and cerebellum. These drug-induced activations might be directly related to intervening sleepiness and to the consequent effort in keeping attention focused on the tasks. The effects of DDS2700 on glucose metabolism at rest, and on rCBF during activation conditions, indicate a drug action on cerebral networks involved in alertness, vigilance and attention maintenance. PET assessment by [18F]FDG and water may provide complementary information in pharmacodynamic studies.


Assuntos
Ansiolíticos/farmacologia , Atenção/fisiologia , Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Fluordesoxiglucose F18/farmacocinética , Lorazepam/farmacologia , Descanso/fisiologia , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Núcleo Caudado/metabolismo , Cerebelo/metabolismo , Circulação Cerebrovascular/efeitos dos fármacos , Humanos , Lorazepam/análogos & derivados , Masculino , Radioisótopos de Oxigênio/farmacocinética , Placebos , Compostos Radiofarmacêuticos/farmacocinética , Valores de Referência , Fluxo Sanguíneo Regional/efeitos dos fármacos , Método Simples-Cego , Tálamo/metabolismo , Tomografia Computadorizada de Emissão/métodos , Água
18.
Minerva Med ; 91(11-12): 267-74, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11253707

RESUMO

BACKGROUND: To review our experience in infectious diseases diagnosis, using a simple labelling technique. METHODS: We made 101 scans in 91 patients with suspected infectious diseases confirmed by clinical, histologic or cultural specimens; a clinical or instrumental follow-up was available for every patient. Patients were divided into four subgroups: A: Inflammatory Bowel Diseases; B: Septic Syndromes; C: Bone diseases; D: Others. We used 99mTc-HMPAO in 80 scans and 111In in 21. In 20/80 frozen and stored HMPAO was used. RESULTS: 99mTc-HMPAO frozen and stored labelling yield was: 60%(SD15%), 99mTcHMPAO: 62(12)(p n.s.), 111In 75%(10%), (p < 0.05). Frozen-stored HMPAO was sterile and apyrogen. 27 had positive scan without leukocytosis or neutrophilia. No correlation between leukocytosis or neutrophilia and yield was observed. Transit lung times ranged between 14-16 min without differences among three radiopharmaceuticals. In each Group and in the sample as a whole True Positive, False Positive, True Negative, False Negative, Sensitivity, Specificity and Accuracy, were calculated. In Group B and in the sample as a whole Predictive Positive Value and Negative Predictive Value were also evaluated. CONCLUSIONS: Labelling yields and "viability" were good using the three radiopharmaceuticals; labelling procedure was simple and safe. Accuracy PPV, NPV, cost-effectiveness were good; 111In is the choice for diagnosis of bone and joint infections. Frozen-stored HMPAO should be introduced as a cost-saving labelling procedure in practice.


Assuntos
Doenças Ósseas Infecciosas/diagnóstico por imagem , Radioisótopos de Índio , Doenças Inflamatórias Intestinais/diagnóstico por imagem , Leucócitos , Compostos Organometálicos , Oxiquinolina/análogos & derivados , Compostos Radiofarmacêuticos , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico por imagem , Tecnécio Tc 99m Exametazima , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Inflamação/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Cintilografia , Sensibilidade e Especificidade
19.
Ital Heart J Suppl ; 1(6): 790-6, 2000 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-11204012

RESUMO

BACKGROUND: Gated-SPECT using 99mTc-labeled flow tracers provides the simultaneous assessment of global and regional myocardial perfusion and function. The aim of this study was to identify patients with stress-induced postischemic stunning, among those with reversible stress perfusion defects, and patients with artifactual defects among those with fixed defects, in order to assess the value of the functional data provided by gated acquisition of perfusion imaging in the characterization of ischemia. METHODS: We studied 221 consecutive patients who underwent conventional diagnostic dual day stress/rest gated-SPECT following injection of 925 MBq of 99mTc-tetrofosmin using a dual head SPECT camera, 115 of whom (52%) showed reversible perfusion defects, and 66 (30%) fixed defects. Perfusion was analyzed on ungated images using 20 segments scored on a 5-point scale (0 = normal, 4 = no uptake), while wall thickening was assessed visually on stress/rest end-systolic images using a 4-point score (0 = normal, 3 = absence of wall thickening). Left ventricular ejection fraction and volumes were calculated using an automatic algorithm (quantitative gated-SPECT). Fifty-two out of 221 (23.5%) patients underwent coronary angiography. RESULTS: In 40/115 (35%) patients with reversible perfusion defects, post-stress left ventricular ejection fraction was > 5% lower than that at rest (Group A: stunned), whereas in the remaining 75 patients, post-stress left ventricular ejection fraction was either +/- 5% or greater than that at rest (Group B: non-stunned). Peak exercise angina and ischemic electrocardiographic response to exercise were present in 79 and 58% respectively of Group A patients and in 33 and 39% of Group B patients. The number of patients with multivessel disease was significantly higher in Group A compared to Group B (58 vs 41%, p < 0.05). The total stress and rest perfusion scores were significantly higher in Group A than in Group B (p < 0.01); even the total stress wall thickening score was significantly higher in Group A (p < 0.001). As for global parameters, post-stress end-systolic volume was significantly higher in the stunned group (p < 0.05). In 40 out of 66 (60.5%) patients without reversible ischemia fixed defects were judged to be ischemic (Group C), while in 26/66 (39.5%) they were attributed to attenuation artifacts (Group D). Eighty percent of Group C patients had a previous myocardial infarction against none of Group D. Stress/rest perfusion and wall thickening scores were significantly higher in Group C than in Group D. CONCLUSIONS: Gated-SPECT myocardial perfusion evaluation allowed us to identify a subgroup of post-stress stunned coronary artery diseased patients. The post-stress left ventricular ejection fraction reduction in this population seems to be due to the increase in end-systolic volume. The stunned patients showed more severe perfusion defects and wall thickening abnormalities.


Assuntos
Imagem do Acúmulo Cardíaco de Comporta , Miocárdio Atordoado/diagnóstico por imagem , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Ann Ig ; 16(4): 569-78, 2004.
Artigo em Italiano | MEDLINE | ID: mdl-15366515

RESUMO

As a result of Italian law, DPR 15/7/2003 n. 254, about hospital waste, and given that little has been written about recycling waste glass in hospitals, a survey of 28 health departments in Lazio was performed. The objectives were: to estimate the mean quantity of clear vitreous waste in one year, to estimate how vitreous waste is administered, to estimate the extent of the use of plastic instead of glass, to analyse the costs and benefits of glass use and/or plastic use and to evaluate staff training about hospital waste disposal. The average production of clear vitreous waste was 0.28 kilogram per day per hospital bed occupied. (This would be the theoretical maximum quantity of glass to be recycled). Among the 28 departments studied, 82% separated waste products but only 36% disposed of glass in accordance with the law. The estimated possible savings on glass phleboclysis in 2002 year were 35,000 euro. Staff training could avoid this conspicuous waste of money. Fifteen departments also used plastic phleboclysis; of these, in 2 departments plastic waste is separated in the wards, but unfortunately this material is later disposed of in the bins for general solid urban waste. The other thirteen hospitals dispose of waste plastic as infectious material. Using glass phleboclysis instead of plastic phleboclysis would save about 680,000 euros per year. The disposal of glass waste material in practice was not found to follow the principles taught in the training courses. Theoretic data about glass production, estimated in this survey, refers only to clear glass and it is an underestimate of that of all glass used in departments. The quantity of glass actually recycled has been about 0.14 kilogram per day per hospital bed occupied and thus only 50% of the theoretical quantity (0.28 kilogram per day per hospital bed occupied). This percentage could be improved by effective training. Ideally, the disposal of waste glass would follow the legal requirements and be monitored locally.


Assuntos
Vidro , Eliminação de Resíduos/normas , Coleta de Dados , Itália , Eliminação de Resíduos/estatística & dados numéricos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA