ABSTRACT
Abstract The goal of this work is to identify new fatty acid-mimetic 99mTc-complexes to be used as myocardial imaging agents that allow studying heart abnormalities in high-risk patients. In this sense, we designed a fatty acid-mimetic substructure including an amide moiety that, among other properties, could improve myocardial residence time. A diamide with a chain length of 15 atoms and porting a 6-hydrazinonicotinyl (HYNIC) chelator, and an analog with a short carbon-chain, were prepared with convergent organic synthetic procedures and radiolabeled with 99mTc using tricine as the sole coligand. The in vivo proofs of concept were performed using healthy mice. The new 99mTc-complexes were obtained with adequate radiochemical purity. The lipophilicities were in agreement with the length of the chains. While both 99mTc-complexes showed uptake in the myocardial muscle, the designed radiopharmaceutical with the longest chain length had preferential target-uptake and target-retention compared to other complexes described in the bibliography. Further studies, involving imaging assays, synthetic modifications, and assay of new coligands for 99mTc-HYNIC complexes, are currently ongoing.
Subject(s)
Animals , Female , Mice , Radiopharmaceuticals/adverse effects , Fatty Acids/agonists , Amides/adverse effects , Heart Defects, Congenital/classificationABSTRACT
In clinical practice, radiopharmaceutical dynamic imaging technology requires the bolus injection method to complete injection. Due to the failure rate and radiation damage of manual injection, even experienced technicians still bear a lot of psychological burden. This study combined the advantages and disadvantages of various manual injection modes to develop the radiopharmaceutical bolus injector, and explored the application of automatic injection in the field of bolus injection from four aspects: radiation protection, occlusion response, sterility of injection process and effect of bolus injection. Compared with the current mainstream manual injection method, the bolus manufactured by the radiopharmaceutical bolus injector based on the automatic hemostasis method had a narrower full width at half maximum and better repeatability. At the same time, radiopharmaceutical bolus injector had reduced the radiation dose of the technician's palm by 98.8%, and ensured more efficient vein occlusion recognition performance and sterility of the entire injection process. The radiopharmaceutical bolus injector based on automatic hemostasis has application potential in improving the effect and repeatability of bolus injection.
Subject(s)
Radiopharmaceuticals , Injections , HandABSTRACT
Radiopharmaceutical dynamic imaging typically necessitates intravenous injection via the bolus method. However, manual bolus injection carries the risk of handling errors as well as radiological injuries. Hence, there is potential for automated injection devices to replace manual injection methods. In this study, the effect of micro-bolus pulse injection technology was compared and verified by radioactive experiments using a programmable injection pump, and the overall bubble recognition experiment and rat tail vein simulation injection verification were performed using the piezoelectric sensor preloading method. The results showed that at the same injection peak speed, the effective flushing volume of micro-bolus pulse flushing (about 83 μL/pulse) was 49.65% lower than that of uniform injection and 25.77% lower than that of manual flushing. In order to avoid the dilution effect of long pipe on the volume of liquid, the use of piezoelectric sensor for sealing preloading detection could accurately predict the bubbles of more than 100 μL in the syringe. In the simulated injection experiment of rat tail vein, when the needle was placed in different tissues by preloading 100 μL normal saline, the piezoelectric sensor fed back a large difference in pressure attenuation rate within one second, which was 2.78% in muscle, 17.28% in subcutaneous and 54.71% in vein. Micro-bolus pulse injection method and piezoelectric sensor sealing preloading method have application potential in improving the safety of radiopharmaceutical automatic bolus injection.
Subject(s)
Animals , Rats , Radiopharmaceuticals/administration & dosageABSTRACT
ABSTRACT Positron emission tomography (PET) is a non-invasive nuclear imaging technique that uses radiotracers to track cell activity. The radiopharmaceutical 18F-fluoro-2-deoxyglucose ([18F] FDG) is most commonly used in nuclear medicine for the diagnosis of various diseases, including stroke. A stroke is a serious condition with high mortality and morbidity rates. Rosmarinic acid (RA) is a promising therapeutic agent that exerts neuroprotective effects against various neurological diseases. Therefore, this study aimed to evaluate the applicability of [18F]FDG/PET for investigating the neuroprotective effects of RA in case of a global stroke model in mice. The [18F]FDG/PET technique facilitates the observation of ischemia and reperfusion injuries in the brain. Moreover, the recovery of glucose metabolism in three specific brain regions, the striatum, superior colliculus, and inferior colliculus, was observed after preconditioning with RA. It was concluded that the [18F]FDG/PET technique may be useful for stroke diagnosis and the assessment of treatment response. In addition, a long-term longitudinal study using biochemical analysis in conjunction with functional imaging may provide further conclusive results regarding the effect of RA on cerebral ischemia.
Subject(s)
Animals , Male , Mice , Stroke/pathology , Positron-Emission Tomography/instrumentation , Brain Ischemia/pathology , Neuroprotective Agents/agonists , Radiopharmaceuticals/pharmacologyABSTRACT
Las amiloidosis son enfermedades causadas por el depósito patológico extracelular de un material proteico fibrilar e insoluble denominado amiloide, que puede estar vinculado a cadenas livianas (AL) o transtirretina (TTR). La amiloidosis cardíaca provoca una cardiomiopatía restrictiva de carácter progresivo caracterizada por falla cardíaca con función sistólica relativamente preservada, que se asocia a elevada mortalidad. Aunque el diagnóstico definitivo tradicionalmente se basa en la biopsia endomiocárdica, los avances en imagenología han mejorado su abordaje y la reciente introducción de terapias especificas permiten augurar cambios significativos en el pronóstico. El tratamiento difiere según el tipo de amiloide involucrado y su resultado depende de la instauración precoz de este, por lo cual resulta esencial un diagnóstico preciso y temprano. El centellograma cardíaco con fosfatos marcados (99mTc-PYP u otros), ampliamente disponible y de relativo bajo costo, se considera en la actualidad como una "biopsia molecular no invasiva" para el diagnóstico de la amiloidosis tipo ATTR, que debe ser usado en conjunto con la investigación de proteínas monoclonales en pacientes con sospecha clínica de la enfermedad.
Amyloidoses are diseases caused by the extracellular deposition of a fibrillar and insoluble protein material called amyloid, which can be linked either to light chains (AL) or transthyretin (TTR). Cardiac amyloidosis causes a progressive restrictive cardiomyopathy characterized by heart failure with relatively preserved systolic function, which is associated with high mortality. Although a definitive diagnosis is traditionally based on endomyocardial biopsy, advances in cardiac imaging have improved its approach, and the recent introduction of specific therapies predicts significant changes in prognosis. Since treatment differs according to the type of amyloid involved and the results depend on a prompt implementation, an accurate and early diagnosis is essential. Cardiac scintigraphy with labeled phosphates (99mTc-PYP or others), widely available and relatively inexpensive, is currently considered a "noninvasive molecular biopsy" for the diagnosis of ATTR type amyloidosis, which should be used in conjunction with investigation of monoclonal proteins in patients with clinical suspicion of the disease.
As amiloidoses são doenças causadas pela deposição patológica extracelular de um material proteico fibrilar e insolúvel, denominado amiloide, que pode estar ligado a cadeias leves (AL) ou transtirretina (TTR). A amiloidose cardíaca causa cardiomiopatia restritiva progressiva caracterizada por insuficiência cardíaca com função sistólica relativamente preservada, que está associada a alta mortalidade. Embora o diagnóstico definitivo seja tradicionalmente baseado na biópsia endomiocárdica, os avanços nos exames de imagem aprimoraram sua abordagem e a recente introdução de terapias específicas pode predizer mudanças significativas no prognóstico. O tratamento varia de acordo com o tipo de amiloide envolvida e seu resultado depende do início precoce, por isso um diagnóstico preciso e precoce é essencial. A cintilografia cardíaca com fosfatos marcados (99mTc-PYP ou outros), amplamente disponível e relativamente econômico, é atualmente considerada uma "biópsia molecular não invasiva" para o diagnóstico de amiloidose do tipo ATTR, que deve ser usada em conjunto com a investigação de proteínas monoclonais em pacientes com suspeita clínica da doença.
Subject(s)
Humans , Radionuclide Imaging/methods , Technetium Tc 99m Pyrophosphate , Radiopharmaceuticals , Amyloidosis/diagnostic imaging , Cardiomyopathies/diagnostic imaging , Radioactive Tracers , Predictive Value of TestsABSTRACT
ABSTRACT BACKGROUND: Clinical assessment of head and neck cancers is highly challenging owing to the complexity of regional anatomy and wide range of lesions. The diagnostic evaluation includes detailed physical examination, biopsy and imaging modalities for disease extent and staging. Appropriate imaging is done to enable determination of precise tumor extent and involvement of lymph nodes, and detection of distant metastases and second primary tumors. OBJECTIVE: To evaluate the initial staging discrepancy between conventional contrasted computed tomography (CT) and 18F-fluorodeoxy-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) and its impact on management plans for head and neck malignancies. DESIGN AND SETTING: Prospective cross-sectional study in two tertiary-level hospitals. METHODS: This study included 30 patients with primary head and neck malignant tumors who underwent contrasted computed tomography and whole-body 18F-FDG PET/CT assessments. The staging and treatment plans were compared with the incremental information obtained after 18F-FDG PET/CT. RESULTS: 18F-FDG PET/CT was found to raise the stage in 33.3% of the cases and the treatment intent was altered in 43.3% of them, while there was no management change in the remaining 56.7%. 18F-FDG PET/CT had higher sensitivity (96% versus 89.2%) and accuracy (93% versus 86.7%) than conventional contrast-enhanced computed tomography. CONCLUSION: Our study demonstrated that 18F-FDG PET/CT had higher sensitivity and accuracy for detecting head and neck malignancy, in comparison with conventional contrast-enhanced computed tomography. 18F-FDG PET/CT improved the initial staging and substantially impacted the management strategy for head and neck malignancies.
Subject(s)
Humans , Positron Emission Tomography Computed Tomography/methods , Head and Neck Neoplasms/therapy , Head and Neck Neoplasms/diagnostic imaging , Cross-Sectional Studies , Prospective Studies , Sensitivity and Specificity , Radiopharmaceuticals , Fluorodeoxyglucose F18 , Positron-Emission Tomography , Neoplasm StagingABSTRACT
BACKGROUND: 18F-fluorodesoxyglucose positron emission tomography/ computed tomography (PET-CT) has a high sensitivity and specificity to detect medullary and extramedullary lesions in multiple myeloma (MM). AIM: To describe the findings of PET-CT in extramedullary multiple myeloma (EMM) at diagnosis and at relapse, and correlate its results with clinical variables, response to treatment and survival. MATERIALS AND METHODS: Review of medical records and PET-CT reports of 39 patients with multiple myeloma (MM) who had at least one PET-CT study, treated between January 1, 2015, and January 1, 2019 at a clinical hospital. RESULTS: The Standard Uptake Values for each hypermetabolic lesion were not described in PET-CT reports. Fifteen patients had an EMM and in eight, without a previous clinical suspicion, PET-TC lead to the diagnosis. The mortality rate in the 39 patients with MM was 46%. Sixty seven percent of deaths occurred in patients with EMM. CONCLUSIONS: PET-TC was useful to diagnose EMM. However, a standardization in PETCT reports would be required to unify criteria. As previously reported, EMM had a greater aggressiveness and lower survival.
Subject(s)
Humans , Positron Emission Tomography Computed Tomography/methods , Multiple Myeloma/drug therapy , Multiple Myeloma/diagnostic imaging , Radiopharmaceuticals , Fluorodeoxyglucose F18 , Positron-Emission Tomography/methods , Neoplasm Recurrence, LocalABSTRACT
Objective: To investigate the clinical value of pretreatment 18F-fluorodeoxy glucose positron emission tomography/computed tomography (18F-FDG PET-CT) in extranodal NK/T-cell lymphoma. Methods: Eighty-one patients with pathologically confirmed extranodal NK/T-cell lymphoma and pretreatment with PET-CT scan in Cancer Hospital, Chinese Academy of Medical Sciences from August 2006 to December 2017 were enrolled in the study. The clinical, follow-up and imaging data were analyzed retrospectively. The relationship between maximum standard uptake value (SUVmax) and prognosis were evaluated by Mann-Whitney U test and Spearman rank correlation analysis. Results: Among the 81 patients, 98.8% (80/81) were upper aerodigestive tract (UAT) involved. Lesions at extra-UAT sites were detected in 7 cases, involving parotid gland (n=1), breast (n=1), spleen (n=1), pancreas (n=1), skin and subcutaneous soft tissue (n=1), muscle (n=1), lung (n=2) and bone (n=3). Lymph node involvement were demonstrated in 33 cases. All of the lesions had increased uptake of PET, the median SUVmax was 8.6. PET-CT changed staging in 15 cases, and 12 cases were adjusted treatment methods. 21 cases were changed radiotherapy target because of PET-CT. The 1-, 2-year progression-free survival (PFS) rates were 88.7% and 80.3% while 1-, 2-year overall survival (OS) rates were 97.2% and 94.4% respectively. The median SUVmax of patients with local lymph nodes involvement was significantly higher than those without local lymph nodes involvement (P=0.007). The SUVmax was positively associated with Ann Arbor stage (r=0.366, P=0.001), lactate dehydrogenase (r=0.308, P=0.005) and Ki-67 level (r=0.270, P=0.017). The SUVmax was inversely associated with lymphocyte count (r=-0.324, P=0.003) and hemoglobin content (r=-0.225, P=0.043). Conclusions: Extranodal NK/T-cell lymphoma predominantly occurs in extra-nodal organs, mainly in the upper respiratory and gastrointestinal tracts, with marked FDG-addiction. Compared with conventional imaging, 18F-FDG PET-CT is sensitive and comprehensive in detecting extra-nodal NK/T-cell lymphoma involvement, assisting in accurate clinical staging and treatment planning. Pretreatment SUVmax is potential for prognosis evaluation since it is correlated with prognostic factors.
Subject(s)
Humans , Fluorodeoxyglucose F18 , Lymphoma, Extranodal NK-T-Cell/radiotherapy , Positron Emission Tomography Computed Tomography/methods , Prognosis , Radiopharmaceuticals , Retrospective StudiesABSTRACT
Objective: Solid and micropapillary pattern are highly invasive histologic subtypes in lung adenocarcinoma and are associated with poor prognosis while the biopsy sample is not enough for the accurate histological diagnosis. This study aims to assess the correlation and predictive efficacy between metabolic parameters in (18)F-fluorodeoxy glucose positron emission tomography/computed tomography ((18)F-FDG PET-CT), including the maximum SUV (SUV(max)), metabolic tumor volume (MTV), total lesion glycolysis (TLG) and solid and micropapillary histological subtypes in lung adenocarcinoma. Methods: A total of 145 resected lung adenocarcinomas were included. The clinical data and preoperative (18)F-FDG PET-CT data were retrospectively analyzed. Mann-Whitney U test was used for the comparison of the metabolic parameters between solid and micropapillary subtype group and other subtypes group. Receiver operating characteristic (ROC) curve and areas under curve (AUC) were used for evaluating the prediction efficacy of metabolic parameters for solid or micropapillary patterns. Univariate and multivariate analyses were conducted to determine the prediction factors of the presence of solid or micropapillary subtypes. Results: Median SUV(max) and TLG in solid and papillary predominant subtypes group (15.07 and 34.98, respectively) were significantly higher than those in other subtypes predominant group (6.03 and 10.16, respectively, P<0.05). ROC curve revealed that SUV(max) and TLG had good efficacy for prediction of solid and micropapillary predominant subtypes [AUC=0.811(95% CI: 0.715~0.907) and 0.725(95% CI: 0.610~0.840), P<0.05]. Median SUV(max) and TLG in lung adenocarcinoma with the solid or micropapillary patterns (11.58 and 22.81, respectively) were significantly higher than those in tumors without solid and micropapillary patterns (4.27 and 6.33, respectively, P<0.05). ROC curve revealed that SUV(max) and TLG had good efficacy for predicting the presence of solid or micropapillary patterns [AUC=0.757(95% CI: 0.679~0.834) and 0.681(95% CI: 0.595~0.768), P<0.005]. Multivariate logistic analysis showed that the clinical stage (Stage Ⅲ-Ⅳ), SUV(max) ≥10.27 and TLG≥7.12 were the independent predictive factors of the presence of solid or micropapillary patterns (P<0.05). Conclusions: Preoperative SUV(max) and TLG of lung adenocarcinoma have good prediction efficacy for the presence of solid or micropapillary patterns, especially for the solid and micropapillary predominant subtypes and are independent factors of the presence of solid or micropapillary patterns.
Subject(s)
Humans , Adenocarcinoma of Lung/diagnostic imaging , Fluorodeoxyglucose F18/metabolism , Lung Neoplasms/pathology , Multimodal Imaging/methods , Positron Emission Tomography Computed Tomography , Positron-Emission Tomography/methods , Prognosis , Radiopharmaceuticals , Retrospective Studies , Tomography, X-Ray Computed/methods , Tumor BurdenSubject(s)
Humans , Male , Female , Myocardial Reperfusion/methods , Myocardial Ischemia/diagnostic imaging , Radiopharmaceuticals/therapeutic use , Acute Coronary Syndrome/diagnostic imaging , Radionuclide Imaging/methods , Echocardiography, Stress/methods , Dipyridamole/adverse effects , Dobutamine/adverse effects , Exercise Test/drug effectsABSTRACT
Resumo A hiperativação do sistema nervoso simpático desempenha um papel central na fisiopatologia da hipertensão. O objetivo deste estudo foi avaliar a atividade simpática cardíaca e investigar o papel da cintigrafia miocárdica com metaiodobenzilguanidina com 123I ([123I] MIBG) na estratificação de risco cardiovascular de pacientes com hipertensão resistente tratados com denervação renal (DR). Dezoito pacientes foram incluídos neste estudo prospectivo (média de idade de 56 ± 10 anos, 27,8% mulheres). Ecocardiograma transtorácico, análise geral do sangue e cintilografia miocárdica com [(123I) MIBG] foram realizados antes e seis meses após a DR. Um paciente era considerado respondedor (R) se uma diminuição ≥ 5 mmHg na pressão arterial sistólica (PAS) média ambulatorial fosse observada no seguimento de seis meses. 66,7% dos pacientes foram R (diminuição na PAS de 20,6 ± 14,5 mmHg, vs. menos 8 ± 11,6 mmHg em não-respondedores (NR), p = 0,001). A relação coração-mediastino (RCM) inicial foi significativamente menor na linha basal no grupo R (1,6 ± 0,1 vs. 1,72 ± 0,1, p <0,02), mas semelhante em seis meses. Considerando os dois momentos no tempo, o grupo R teve valores iniciais de RCM mais baixos do que o grupo NR (p <0,05). Tanto o RCM tardio quanto a taxa de washout foram idênticos e nenhuma correlação significativa entre a resposta à DR ou qualquer índice de imagem com MIBG foi encontrada. A denervação renal efetivamente reduziu a pressão arterial na maioria dos pacientes, mas a imagem com [123I] MIBG não foi útil na previsão da resposta. Entretanto, houve evidência de overdrive do sistema nervoso simpático e, tanto a RCM inicial quanto tardia estavam reduzidas em geral, provavelmente colocando essa população em um risco maior de eventos adversos.
Abstract Hyperactivation of the sympathetic nervous system plays a central role in the pathophysiology of hypertension. The aim of this study was to assess cardiac sympathetic activity and investigate the role of myocardial123I-labelled meta-iodo benzyl guanidine ([123I] MIBG) scintigraphy in cardiovascular risk stratification of patients with resistant hypertension treated with renal denervation (RDN). Eighteen patients were included in this prospective study (mean age 56 ± 10 years old, 27.8% females). Transthoracic echocardiogram, general blood analysis and myocardial ([123I] MIBG scintigraphy were performed before and six-months after RDN. A patient was considered a responder (R) if a drop ≥ 5mmHg on mean systolic ambulatory blood pressure (BP) monitoring was observed at the six-month follow-up. 66.7% of patients were R (drop in systolic BP of 20.6 ± 14.5mmHg, vs minus 8 ± 11.6mmHg in non-responders (NR), p=0.001). Early heart-mediastinum ratio (HMR) was significantly lower at baseline in the R group (1.6 ± 0.1 vs 1.72 ± 0.1, p<0.02) but similar at six months. Considering both instants in time, the R group had lower early HMR values than the NR group (p<0.05). Both the late HMR and the washout rate were identical and no significant correlation between response to RDN or any MIBG imaging index was found. Renal denervation effectively lowered blood pressure in the majority of patients but [123I] MIBG was not useful in predicting the response. However, there was evidence of sympathetic overdrive and, both early and late HMR were overall reduced, probably putting this population at a higher risk of adverse events.
Subject(s)
Humans , Male , Female , Aged , Blood Pressure Monitoring, Ambulatory , 3-Iodobenzylguanidine , Sympathetic Nervous System/diagnostic imaging , Prospective Studies , Risk Assessment , Radiopharmaceuticals , Denervation , Heart/physiology , Heart/diagnostic imaging , Iodine Radioisotopes , Middle AgedABSTRACT
ABSTRACT Introduction: Prostate cancer (PC) is the second most commonly diagnosed cancer in males. 68Ga-PSMA PET/CT, a non-invasive diagnostic tool to evaluate PC with prostate-specific membrane antigen (PSMA) expression, has emerged as a more accurate alternative to assess disease staging. We aimed to identify predictors of positive 68Ga-PSMA PET and the accuracy of this technique. Materials and methods: Diagnostic accuracy cross-sectional study with prospective and retrospective approaches. We performed a comprehensive literature search on PubMed, Cochrane Library, and Embase database in search of studies including PC patients submitted to radical prostatectomy or radiotherapy with curative intent and presented biochemical recurrence following ASTRO 1996 criteria. A total of 35 studies involving 3910 patients submitted to 68-Ga-PSMA PET were included and independently assessed by two authors: 8 studies on diagnosis, four on staging, and 23 studies on restaging purposes. The significance level was α=0.05. Results: pooled sensitivity and specificity were 0.90 (0.86-0.93) and 0.90 (0.82-0.96), respectively, for diagnostic purposes; as for staging, pooled sensitivity and specificity were 0.93 (0.86-0.98) and 0.96 (0.92-0.99), respectively. In the restaging scenario, pooled sensitivity and specificity were 0.76 (0.74-0.78) and 0.45 (0.27-0.58), respectively, considering the identification of prostate cancer in each described situation. We also obtained specificity and sensitivity results for PSA subdivisions. Conclusion: 68Ga-PSMA PET provides higher sensitivity and specificity than traditional imaging for prostate cancer.
Subject(s)
Humans , Male , Prostatic Neoplasms/diagnostic imaging , Positron Emission Tomography Computed Tomography , Tomography, X-Ray Computed , Cross-Sectional Studies , Prospective Studies , Retrospective Studies , Radiopharmaceuticals , Positron-Emission TomographyABSTRACT
Vasculitides are a broad group of diseases that can involve any kind of vessel in any organ. These can be classified according to the size of the affected vessels. The most used classification categorizes them in small, medium, and large vessel vasculitis. Large vessel vasculitis can be further divided in Takayasu arteritis and giant cell arteritis which can sometimes be indistinguishable, even with biopsy. Radiology plays an important role identifying distribution patterns and disease extension18. Fluorine-Fluorodeoxyglucose (FDG) PET-CT shows increased vessel wall FDG uptake in patients with active large vessel vasculitis. Multiple studies show that FDG PET-CT helps to identify the anatomic structures with the disease, as well as evaluate its progression with a high sensibility and specificity in non-treated patients with large vessel vasculitis.
Subject(s)
Humans , Giant Cell Arteritis/diagnostic imaging , Takayasu Arteritis/diagnostic imaging , Tomography, X-Ray Computed , Radiopharmaceuticals , Fluorodeoxyglucose F18 , Positron-Emission Tomography , Positron Emission Tomography Computed TomographyABSTRACT
Resumen La endocarditis infecciosa (EI) es una enfermedad de alta mortalidad, caracterizada por una infección endocárdica y frecuentes complicaciones multiorgánicas, que requiere un diagnóstico rápido y preciso, y un manejo agresivo, ya sea médico o quirúrgico. Su diagnóstico se realiza tomando en cuenta criterios bacteriológicos, clínicos y ecocardiográficos. Es objetivo de este artículo realizar una actualización del estudio imagenológico en paciente con EI, con especial énfasis en aquellos exámenes no ecocardiográficos disponibles en nuestro medio. En los últimos años, estudios de imagen avanzados han adquirido un rol creciente en su estudio inicial, particularmente la tomografía computada multicorte (TCMC) cardiaca y el positron emission tomography/computed tomography (PET/CT), y han sido recomendados como criterios diagnósticos en las guías recientes para el manejo de esta entidad. La TCMC cardiaca proporciona información anatómica detallada de las válvulas cardiacas y tejido perivalvular, identificando pseudoaneurismas, abscesos y dehiscencias valvulares. El PET/CT con F18-fluorodeoxiglucosa (F18-FDG) permite aumentar la sensibilidad en la detección de EI, y pesquisar con alta eficiencia fenómenos embólicos sistémicos, de elevada frecuencia en esta población. Ambos métodos prestan particular utilidad en EI de válvula protésica, donde la ecocardiografía presenta menor rendimiento diagnóstico. La resonancia magnética (RM) cerebral es el mejor método de imagen para descartar eventos isquémicos/embólicos del sistema nervioso central.
Abstract Infective endocarditis (IE) is an entity characterized by endocardial infection and frequent multiorgan complications, resulting in high mortality. It requires a rapid and accurate diagnosis, and a medical or surgical aggressive treatment. Currently, IE diagnosis rests on bacterial, clinical and ultrasonographic criteria. The objective of this article is to update the imaging study in patients with IE, with special emphasis on those non-echocardiographic examinations available in our environment. Last years, advanced imaging had achieved a growing role in IE diagnosis, especially cardiac multislice computed tomography (MSCT) and positron emission tomography/computed tomography (PET/CT), which have been recommended in recent clinical guidelines to be included as part of diagnostic criteria. Cardiac MSCT provides detailed anatomic information of cardiac valves and perivalve tissue, allowing identification of pseudoaneurysm, abscess and valve dehiscence. F18-FDG PET/CT increases sensitivity for IE detection and shows high accuracy in searching for extracranial systemic embolic events. Both MSCT and PET/CT have particular utility in cases of prosthetic valve endocarditis, where cardiac ultrasonography shows lower performance. Brain magnetic resonance imaging (MRI) is the best imaging method for evaluating ischemic/embolic events of central nervous system.
Subject(s)
Humans , Endocarditis/diagnostic imaging , Endocarditis, Bacterial/diagnostic imaging , Heart Valve Prosthesis/adverse effects , Ultrasonography , Radiopharmaceuticals , Fluorodeoxyglucose F18 , Positron Emission Tomography Computed TomographyABSTRACT
Abstract Introduction: Head and neck squamous cell carcinoma is the seventh most common malignant tumor. The advances in treatment have improved the global survival rates in the past years, although the prognosis is still grave. Objective: The aim of the present study is to evaluate the correlation between positron emission computed tomography and computed tomography at the time of staging a previously untreated head and neck squamous cell carcinoma, and to determine which of the two imaging techniques gives us more information at the time of initial diagnosis. Methods: Data from all patients diagnosed in our hospital of head and neck squamous cell carcinoma by a biopsy of any location or unknown primary tumor was collected, between January 2012 and July 2017. In all cases, computed tomography and positron emission computed tomography were performed with a maximum of 30 days difference between them and patients had not received any prior treatment to staging. The stage given to each case was compared based solely on the physical examination, only on the computed tomography/positron emission computed tomography, with respect to the stage given by the tumor board, observing the concordance obtained through Cramer's V statistical test. Results: We performed a comparative analysis obtaining a correlation of 0.729 between the stage given by the tumor board and the one assigned based on the physical examination without imaging techniques. When only using computed tomography as an imaging method, the correlation was 0.848, whereas with only the use of positron emission computed tomography it was estimated at 0.957. When comparing the statistical association between staging using exclusively one of the two imaging techniques, correlation was 0.855. Conclusion: Positron emission computed tomography is useful for the diagnosis of head and neck squamous cell carcinoma, improving the patient's staging especially when detecting cervical and distant metastases. Therefore, we consider that the use of positron emission computed tomography for the staging of patients with head and neck squamous cell carcinoma is a diagnostic test to be considered.
Resumo Introdução: O carcinoma espinocelular de cabeça e pescoço é o sétimo tumor maligno mais comum. Os avanços no tratamento melhoraram as taxas de sobrevida global nos últimos anos, embora o prognóstico ainda seja grave. Objetivo: Avaliar a correlação entre a tomografia computadorizada por emissão de pósitrons e a tomografia computadorizada no estadiamento de carcinomas espinocelulares da cabeça e pescoço não tratados previamente e verificar qual das duas técnicas de imagem nos fornece mais informações no momento do diagnóstico inicial. Método: Os dados de todos os pacientes diagnosticados em nosso hospital com carcinoma espinocelular de cabeça e pescoço por biópsia de qualquer região ou adenopatias de origem desconhecida foram colhidos no período entre janeiro de 2012 e julho de 2017. Em todos os casos, uma tomografia computadorizada e uma tomografia computadorizada por emissão de pósitrons foram realizadas com um máximo de 30 dias de diferença entre elas. Nenhum paciente deveria ter recebido tratamento antes do estadiamento. O estadiamento atribuído a cada caso foi comparado com base apenas no exame físico, pela tomografia computadorizada ou apenas pela tomografia computadorizada por emissão de pósitrons, com relação ao estadiamento concedido pela margem tumoral, observou-se a concordância obtida pelo teste estatístico de V de Cramer. Resultado: Realizamos a análise comparativa obtendo uma correlação de 0,729 entre o estadio concedido pela margem tumoral e aquele atribuído com base no exame físico sem técnicas de imagem. Usando apenas a tomografia computadorizada como método de imagem, a correlação foi de 0,848, enquanto que a correlação com a tomografia computadorizada por emissão de pósitrons foi estimada em 0,957. Ao comparar a associação estatística entre o estadiamento usando exclusivamente uma das duas técnicas de imagem, foi de 0,855. Conclusão: Tomografia computadorizada por emissão de pósitrons é útil para o diagnóstico de carcinoma espinocelular de cabeça e pescoço, melhora o estadiamento, especialmente na detecção de metástases cervicais e à distância. Portanto, concluimos que seu uso para o estadiamento de pacientes com carcinoma espinocelular de cabeça e pescoço é um exame diagnóstico a ser considerado.
Subject(s)
Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/therapy , Carcinoma, Squamous Cell/diagnostic imaging , Head and Neck Neoplasms/therapy , Head and Neck Neoplasms/diagnostic imaging , Tomography, X-Ray Computed , Sensitivity and Specificity , Radiopharmaceuticals , Fluorodeoxyglucose F18 , Positron Emission Tomography Computed Tomography , Squamous Cell Carcinoma of Head and Neck/diagnostic imaging , Neoplasm StagingABSTRACT
Because of the unobvious early symptoms and low 5-year survival rate, the early diagnosis and treatment is of great significance for patients with non-small cell lung cancer. Glucose transporter-1 is the most widely distributed glucose transporters in various tissue cells in the human body, whose expression in non-small cell lung cancer is closely related to the histological types, lymph node metastasis, degree of differentiation, progression and prognosis.
Subject(s)
Humans , Carcinoma, Non-Small-Cell Lung/diagnostic imaging , Fluorodeoxyglucose F18 , Glucose Transport Proteins, Facilitative , Glucose Transporter Type 1 , Lung Neoplasms/diagnostic imaging , Positron Emission Tomography Computed Tomography , Positron-Emission Tomography , RadiopharmaceuticalsABSTRACT
Objective To design a novel automatic dispensing and injecting system of positron radiopharmaceuticals,for precise dose dispensing,simplified operation,and reduction of occupational radiation exposure. Methods The automatic dispensing and injecting system was fabricated with tungsten alloy as the shielding material.The performance and radiation protection of the device were assessed. Results The total time of injection using the automatic dispensing and injecting system was about 60 s.The ratio of successful injection in stability test was 100%.The deviation of the dispensing dose with the system was ≤3%.With the tungsten alloy shield(40 mmPb of the cabinet,60 mmPb of the countertop,15 mmPb of the protective shield,and 50 mmPb of the inbuilt jar for radiopharmaceuticals),the average dose rate at 30 cm from the device was 1.44 μSv/h,and the radiation dose at the operator's extremity was reduced by 99%. Conclusions This automatic dispensing and injecting system of positron radiopharmaceuticals is easy to operate with precise dispensing dose.It is safe and meets the requirements of radiation protection.
Subject(s)
Electrons , Occupational Exposure/analysis , Radiation Dosage , Radiation Protection , RadiopharmaceuticalsABSTRACT
Introdução: este estudo trata do controle de qualidade do radiofármaco utilizado em estudos de PET-CT para diagnóstico e/ou estadiamento de pacientes acometidos pelo câncer de próstata. Objetivo: avaliar a qualidade do radiofármaco PSMA-11, marcado com uso de gerador de Ge68-Ga68 itinerante. Metodologia: análise do aspecto visual, pH e pureza radioquímica do radiofármaco marcado a cada recebimento do gerador de Ge68-Ga68. Resultado: todas as marcações realizadas se apresentaram límpidas quanto ao aspecto visual, o pH ficou entre 5,0 e 6,0 e a pureza radioquímica apresentou em 92% dos casos valores ≥ 96%. Conclusão: com os devidos controles de qualidade, pode ser uma opção para uso na clínica médica, em serviços que não disponham de condição para adquirir um sistema, por ser importado.
Introduction: this study works with the quality control of the radiopharmaceutical used in PET-CT studies for diagnosis and / or staging of patients affected with prostate cancer. Objective: evaluate the quality of the PSMA-11 marked radiopharmaceutical using a Ge68-Ga68 itinerant generator. Methodology: analysis of the visual aspect, pH and radiochemical purity of the marked radiopharmaceutical on each receiving of the Ge68-Ga68 generator. Results: all performed markings were clear in terms of visual appearance, pH was between 5.0 and 6.0 and radiochemical purity was 92% with value ≥ 96%. Conclusion: with proper quality controls it can be an option for application in the medical clinic, services centers unable to purchase a system due to importation process.