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1.
Medicine (Baltimore) ; 99(2): e18681, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914064

RESUMO

Hyperparathyroidism is a common endocrine disorder. The precise localization of causal parathyroid gland is crucial to guide surgical treatment. Several studies report the added value of 18F-fluorocholine (FCH) positron emission tomography-computed tomography (PET/CT) as second line imaging but rely on suboptimal first-line imaging using 99mTc-sestaMIBI dual phase scintigraphy. The aim of this study is to evaluate the percentage of successful parathyroid localization with FCH PET/CT after failure of a more sensitive first-line detection protocol associating neck ultrasonography and 99mTc-Pertechnetate/99mTc-sestaMIBI dual tracer subtraction scintigraphy.We included retrospectively 47 patients who underwent a FCH PET/CT as second line imaging for biologically proven primary hyperparathyroidism from November 2016 to October 2018 in Godinot Institute (Reims, France). 99mTc-Pertechnetate/99mTc-sestaMIBI dual tracer subtraction scintigraphy and neck ultrasonography were used as first-line imaging and failed to localize the causal parathyroid lesion in all cases.FCH PET/CT demonstrated at least 1 parathyroid target lesion in 29 patients (62%). 21/29 patients underwent surgery. Target lesions corresponded histologically to hyperfunctioning parathyroid glands for all 21 patients and surgery was followed by hyperparathyroidism biological resolution. Calcium serum levels were associated to FCH PET/CT positivity (P = .002) and a trend toward significance was seen for Parathyroid hormone (PTH) levels (P = .09).FCH PET/CT is a promising tool in second-line parathyroid imaging. Large prospective studies and cost-effectiveness analyses are needed to precise its role.


Assuntos
Colina/análogos & derivados , Radioisótopos de Flúor/administração & dosagem , Hiperparatireoidismo/diagnóstico por imagem , Glândulas Paratireoides/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Idoso , Idoso de 80 Anos ou mais , Colina/administração & dosagem , Feminino , Humanos , Hiperparatireoidismo/patologia , Masculino , Pessoa de Meia-Idade , Glândulas Paratireoides/patologia , Cintilografia/métodos , Estudos Retrospectivos , Tecnécio Tc 99m Sestamibi/administração & dosagem
2.
Medicine (Baltimore) ; 99(4): e18905, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31977903

RESUMO

Although pathological confirmation is the gold standard for diagnosis of amyloidosis, there is a need for a relevant imaging modality to identify involved organs and evaluate disease extent. Thus, we prospectively investigated imaging findings of Tc-DPD scintigraphy in AL and ATTR amyloidosis.A total of 21 subjects with pathologically confirmed AL or ATTR amyloidosis were included. Pretreatment whole body Tc-DPD planar scanning and regional SPECT/CT were performed in all subjects. For allegedly involved organs, Tc-DPD uptake was visually and semi-quantitatively evaluated on a 4-point scale (grade 0: no uptake, 1: uptake less than spine, 2: uptake similar to spine, and 3: uptake greater than spine).There were 29 organs involved in AL and 12 in ATTR. Significant Tc-DPD uptake was found in 24 organs (sensitivity = 82.8%) in AL and 9 organs (sensitivity = 75.0%) in ATTR. Additional SPECT/CT was helpful to ensure abnormal DPD uptake in the involved organs, which was uncertain by attenuation in planar imaging. Degree of Tc-DPD uptake was significantly higher in ATTR compared with AL amyloidosis (P = .017). Diffuse soft tissue uptake with photon defects in the liver area was found only in ATTR amyloidosis.This study showed that Tc-DPD scintigraphy might have capacity to differentiate between AL and ATTR subtypes with good sensitivity in various organs involving primary systemic AL and ATTR amyloidosis. Additional SPECT/CT significantly improved the diagnostic efficacy of Tc-DPD scintigraphy.


Assuntos
Neuropatias Amiloides Familiares/diagnóstico por imagem , Amiloidose de Cadeia Leve de Imunoglobulina/diagnóstico , Cintilografia/métodos , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos de Organotecnécio/administração & dosagem , Imagem Corporal Total
3.
Medicine (Baltimore) ; 98(38): e17256, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31567998

RESUMO

RATIONALE: Cardiac amyloidosis, considered for the last years to be a rare disease, is one of the determinants of HFpEF. The non-specific clinical presentation and the difficulties related to endomyocardial biopsy have made cardiac amyloidosis an underdiagnosed clinical entity. Improvement of non-invasive diagnostic techniques and the development of new therapies increased clinical awareness for this form of restrictive cardiomyopathy. We here summarize echocardiography and Tc-HDP scintigraphy findings in 6 cases of cardiac amyloidosis and review the literature data of this progressive and fatal cardiomyopathy. PATIENTS CONCERNS: The main clinical manifestations were fatigue, low exercise tolerance and edemas. The right heart failure symptoms usually dominated the clinical picture. DIAGNOSES: All cases were evaluated by echocardiography; 3 cases were further examined by bone scintigraphy and 4 cases a peripheral biopsy was performed. Electrocardiography showed low-voltage QRS complexes and "pseudo-infarct" pattern in the precordial leads, contrary to the echocardiographic aspect, which revealed thickening of ventricle walls. Biatrial dilation and diastolic disfunction were observed. Impaired systolic function was detected in advanced stages of the disease. Tc-HDP scintigraphy revealed cardiac uptake of radiopharmaceutical and managed to confirm the diagnosis in 1 case of cardiac amyloidosis in which salivary gland biopsy was negative. INTERVENTIONS: The treatment was based on managing fluid balance, with the mainstream therapy represented by diuretics. Neurohormonal agents, usually used in heart failure treatment were avoided, due to poor tolerance and worsening of disease course. The management of these 6 cases was challenging due to the refractory manifestation of congestive heart failure. OUTCOMES: During follow-up, 4 of the 6 patients from the current study died in the first year after the final diagnosis was established. LESSONS: Nuclear imaging of cardiac amyloidosis has a revolutionary development nowadays. Bone scintigraphy presents promising results for identifying patients at early stages of disease and to differentiate between cardiac amyloidosis types. Further studies are necessary for the standardization of imaging protocol and development of non-invasive diagnostic tools, especially in assessing the response to treatment and disease progression, for which little is known.


Assuntos
Amiloidose/diagnóstico por imagem , Ecocardiografia , Cardiopatias/diagnóstico por imagem , Cintilografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Amiloidose/diagnóstico , Amiloidose/patologia , Difosfonatos , Feminino , Coração/diagnóstico por imagem , Cardiopatias/diagnóstico , Cardiopatias/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Compostos de Organotecnécio
4.
Pharm Res ; 36(10): 143, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31385111

RESUMO

PURPOSE: Pancreatic Polypeptide-secreting tumor of the distal pancreas (PPoma) is a rare, difficult and indolent type of cancer with a survival rate of 5-year in only 10% of all cases. The PPoma is classified as a neuroendocrine tumor (NET) not functioning that overexpresses SSTR 2 (somatostatin receptor subtype 2). Thus, in order to improve the diagnosis of this type of tumor, we developed nanoparticulate drug carriers based on poly-lactic acid (PLA) polymer loaded with octreotide and radiolabeled with Technetium-99 m (99mTc). METHODS: PLA/PVA octreotide nanoparticles were developed by double-emulsion technique. These nanoparticles were characterized by Atomic Force Microscopy (AFM) and Dynamic Light Scattering (DLS) and radiolabeled with 99mTc by the direct via forming 99mTc-PLA/PVA octreotide nanoparticles. The safety of these nanosystems was evaluated by the MTT cell toxicity assay and their in vivo biodistribution was evaluated in xenografted inducted animals. RESULTS: The results showed that a 189 nm sized nanoparticle were formed with a PDI of 0,097, corroborating the monodispersive behavior. These nanoparticles were successfully radiolabeled with 99mTc showing uptake by the inducted tumor. The MTT assay corroborated the safety of the nanosystem for the cells. CONCLUSION: The results support the use of this nanosystem (99mTc-PLA/PVA octreotide nanoparticles) as imaging agent for PPoma. Graphical Abstract Polypeptide-Secreting Tumor of the Distal Pancreas (PPoma) Radiolabeled Nanoparticles for Imaging.


Assuntos
Carcinoma Ductal Pancreático/diagnóstico por imagem , Nanopartículas/química , Octreotida/química , Neoplasias Pancreáticas/diagnóstico por imagem , Polipeptídeo Pancreático/metabolismo , Poliésteres/química , Compostos Radiofarmacêuticos/química , Tecnécio/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/metabolismo , Octreotida/metabolismo , Pâncreas/diagnóstico por imagem , Pâncreas/metabolismo , Neoplasias Pancreáticas/metabolismo , Tamanho da Partícula , Cintilografia/métodos , Compostos Radiofarmacêuticos/metabolismo , Receptores de Somatostatina/genética , Receptores de Somatostatina/metabolismo , Distribuição Tecidual
5.
Am Surg ; 85(7): 742-746, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31405420

RESUMO

Insulinomas are rare endocrine malignancies of the pancreas that require surgical resection but can be difficult to localize preoperatively. We sought to review and improve the accuracy of preoperative localization techniques at our institution. We retrospectively reviewed all insulinomas that underwent resection at our institution between 1998 and 2016. Localization techniques include selective arterial calcium stimulation (CaStim), CT, MRI, angiography, and somatostatin receptor scintigraphy. Thirty-eight patients had pathologically proven insulinomas on surgical resection. Localization accuracies of CaStim, CT, and MRI were 89 per cent (31/35), 67 per cent (22/33), and 46 per cent (11/24), respectively. When compared with CT alone and CaStim alone, the combination of these two modalities resulted in 100 per cent preoperative localization (30/30), whereas the use of CaStim alone resulted in 80 per cent (4/5) localization and the use of CT alone resulted in 66 per cent (2/3) localization. Four of our patients had both negative CT and MRI. Among these patients, CaStim was 100 per cent localizing and the only positive modality for these patients. These data confirm that CaStim is accurate in preoperatively identifying single and multiple insulinomas; and when combined with CT, this accuracy is increased to 100 per cent. Based on these data, we propose that a dual imaging approach is a superior means of preoperative localization.


Assuntos
Insulinoma/diagnóstico por imagem , Imagem Multimodal/métodos , Neoplasias Pancreáticas/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Insulinoma/cirurgia , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Cuidados Pré-Operatórios/métodos , Cintilografia/métodos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Adulto Jovem
6.
Drug Dev Ind Pharm ; 45(10): 1707-1715, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31418304

RESUMO

Numerous normal and tumors cells are well-known to express the somatostatin receptors (SSTRs) on their surface which makes the receptor be useful for tumor scintigraphy. Thus, the identification of SSTRs is beneficial, especially SSTR2. The somatostatin analog, Octreotide (OCT), was chosen as a ligand, as it is known to selectively bind to SSTR2. Moreover, polyethylene glycol (PEG), 8armPEG, was used as a branched PEG to provide a low nonspecific cell binding and easily chemical modification. OCT and fluorescein (Flu) were conjugated to branched PEG using a water-soluble carbodiimide (EDC) and N-hydroxy succinimide (NHS) so as to activate its carboxylic acid group. 8armPEG-tagged Flu and OCT was characterized by gel permeation chromatography (GPC) to proof the conjugation of OCT to 8armPEG. Finally, cellular uptake was studied using pancreatic cancer cells with well-expressed somatostatin receptors using a confocal laser scanning microscope (CLMS) and fluorescence activated cell sorting (FACS). GPC showed increases in molecular mass since it showed a difference in elution time of 8armPEG itself and 8armPEG labeled with Flu. CLMS and FACS showed high binding with the positive SSTR2 cells expression and showed negative results with negative expressing SSTR2. These bindings were decreased when the receptors were occupied with free OCT which confirms the specific binding to SSTR2. Therefore, we formulated a novel model to easily identify SSTR2 and other receptors which serves as a promising platform for identification of tumor cells overexpressing the SSTR2, which would be a hopeful target for cancer therapy and tumor scintigraphy.


Assuntos
Octreotida/metabolismo , Polietilenoglicóis/metabolismo , Receptores de Somatostatina/metabolismo , Somatostatina/metabolismo , Células CACO-2 , Linhagem Celular Tumoral , Células HCT116 , Humanos , Células MCF-7 , Neoplasias Pancreáticas/metabolismo , Cintilografia/métodos
7.
Surgery ; 166(4): 678-685, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31466855

RESUMO

BACKGROUND: Preoperative localization of abnormal parathyroid glands in primary hyperparathyroidism is often obtained by sestamibi, and ultrasonography. We aimed to identify which modality is most accurate when laterality of abnormal glands on preoperative imaging is discordant. METHODS: A single institution retrospective review identified 112 consecutive patients with primary hyperparathyroidism who underwent successful parathyroidectomy and sestamibi with pertechnetate. RESULTS: Sestamibi with pertechnetate had a sensitivity of 72% and positive predictive value of 90%; ultrasonography had sensitivity of 50% and positive predictive value 80%. Patients with thyroiditis had lesser sensitivity and positive predictive value on sestamibi with pertechnetate (53% and 77%, respectively), in contrast to ultrasonography (54%, 88%, respectively). The sensitivity and positive predictive value of sestamibi with pertechnetate and ultrasonography did not differ in patients with thyroid nodules. Seventeen patients (15%) had discordant laterality on preoperative imaging. In discordant cases, sestamibi with pertechnetate was correct in 53% overall but in only 17% of those with thyroiditis (P = .01), whereas ultrasonography was correct in 26% overall but in 50% of those with thyroiditis (P = .01). CONCLUSION: Thyroiditis decreased the sensitivity and positive predictive value of sestamibi with pertechnetate in primary hyperparathyroidism. In patients with discordant laterality on preoperative imaging, sestamibi with pertechnetate is the more accurate choice to guide operative planning, although ultrasonography may be a better guide in those with thyroiditis.


Assuntos
Hiperparatireoidismo/diagnóstico por imagem , Paratireoidectomia/métodos , Cintilografia/métodos , Ultrassonografia Doppler/métodos , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Hiperparatireoidismo/cirurgia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Cuidados Pré-Operatórios/métodos , Estudos Retrospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Tecnécio Tc 99m Sestamibi
8.
Nucl Med Commun ; 40(9): e1-e3, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31365501

RESUMO

The purpose of this guideline is to assist specialists in Nuclear Medicine and Radionuclide Radiology in recommending, performing, interpreting and reporting the results of Parathyroid Scintigraphy. This guideline will assist individual departments to formulate their own local protocols. This does not aim to be prescriptive regarding technical aspects of individual camera acquisitions which need to be developed in conjunction with the local medical physics expert. These guidelines pertain only to adult patients. There are numerous techniques for localizing Parathyroid adenomas. This guideline will describe the use of 99mTc-sestamibi dual phase imaging which may be used alone or in combination with other modalities.


Assuntos
Glândulas Paratireoides/diagnóstico por imagem , Cintilografia/métodos , Humanos , Interpretação de Imagem Assistida por Computador , Guias de Prática Clínica como Assunto , Compostos Radiofarmacêuticos
9.
Clinics (Sao Paulo) ; 74: e835, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31365617

RESUMO

The efficacy and toxicity of radionuclide therapy are believed to be directly related to the radiation doses received by target tissues; however, nuclear medicine therapy continues to be based primarily on the administration of empirical activities to patients and less frequently on the use of internal dosimetry for individual therapeutic planning. This review aimed to critically describe the techniques and clinical evidence of dosimetry as a tool for therapeutic planning and the main limitations to its implementation in clinical practice. The present article is a nonsystematic review of voxel-based dosimetry. Clinical evidence pointing to a correlation between the radiation dose and therapeutic response in various diseases, such as thyroid carcinoma, neuroendocrine tumors and prostate cancer, is reviewed. Its limitations include technical aspects related to image acquisition and processing and the lack of randomized clinical trials demonstrating the impact of dosimetry on patient therapy. A more widespread use of dosimetry in therapeutic planning involves the development of user-friendly dosimetric protocols and confirmation that dose estimation implies good efficacy and low treatment-related toxicity.


Assuntos
Radioisótopos/administração & dosagem , Radiometria/métodos , Cintilografia/métodos , Radioterapia/métodos , Humanos , Tomografia por Emissão de Pósitrons/métodos , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único/métodos
11.
Eur J Endocrinol ; 181(3): 245-253, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31311003

RESUMO

Objective: Despite the improvements in ultrasound (US) and scintigraphy, 10-20% of patients with primary hyperparathyroidism (PHPT) still have discordant findings. We performed a systematic review and meta-analysis to assess the safety and the diagnostic performance of US-guided PTH washout (FNA-PTH) in patients with PHPT, a suspected parathyroid lesion on US but negative or equivocal scintigraphy. Methods: The review was registered on PROSPERO (CRD42019124249). PubMed, Scopus, CENTRAL and Web of Science were searched until February 2019. Original articles reporting complications and diagnostic performance of FNA-PTH in biochemically and histopathologically diagnosed PHPT were selected. The risk of bias of included studies was assessed through QUADAS-2. Summary operating points were estimated using a random-effects model. Results: Out of 2573 retrieved papers, nine cohort studies were included in the review. No major procedure-related complications were found. Pooled sensitivity was 95% (95% CI: 91-98; I 2: = 14%) and positive predictive value was 97% (95% CI: 93-100; I 2: = 39%). There were not enough data for specificity and negative predictive value to perform a meta-analysis. However, pooling results of all lesions, they were estimated to be 83 and 73%, respectively. Conclusions: In patients with biochemically proven PHPT and discordant imaging, FNA-PTH was a safe and accurate procedure. In this specific setting of patients, FNA-PTH could be used as a rule-in test for minimally invasive parathyroidectomy.


Assuntos
Hiperparatireoidismo Primário/sangue , Hiperparatireoidismo Primário/diagnóstico por imagem , Hormônio Paratireóideo/sangue , Paratireoidectomia/métodos , Estudos de Coortes , Humanos , Hiperparatireoidismo Primário/cirurgia , Paratireoidectomia/normas , Cintilografia/métodos , Cintilografia/normas
12.
Medicine (Baltimore) ; 98(30): e16566, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31348283

RESUMO

RATIONALE: Cardiac transthyretin amyloidosis is a progressive and fatal cardiomyopathy for which several promising therapies are in development. The diagnosis is frequently delayed or missed because of the limited specificity of clinical manifestations, routine electrocardiogram, echocardiography and the traditional requirement for endomyocardial biopsy confirmation. PATIENT CONCERNS: A 68-year-old female had suffered from lumbago for 5 years with progressive weakness, numbness in both lower limb. DIAGNOSIS: The patient's clinical signs were not specific, but cardiac amyloidosis was suspected based on relative left ventricular apical sparing of longitudinal strain on echocardiography and continuous elevated serum levels of cardiac biomarkers (ultrasensitive cardiac troponin I and NT-proBNP). She was finally diagnosed hereditary transthyretin-related cardiac amylodosis by specific findings of cardiovascular magnetic resonance imaging (CMR), -technetium pyrophosphate (Tc-PYP) scintigraphy and genetic testing. INTERVENTIONS: The patient received medications including diuretics, beta-blockers and angiotensin-converting enzyme inhibitors at the time of hospitalization. Ultimately, however, she refused further treatments and requested discharge from our hospital. OUTCOMES: A series of noninvasive technique enables the diagnosis of hereditary transthyretin-related cardiac amyloidosis. LESSONS: While endomyocardial biopsy is not able to performed, this case demonstrates that a combination of noninvasive techniques, especially CMR, nuclear imaging, and genetic testing, may help us to make a correct diagnosis of hereditary transthyretin-related cardiac amyloidosis.


Assuntos
Neuropatias Amiloides Familiares/diagnóstico , Técnicas de Imagem Cardíaca/métodos , Testes Genéticos/métodos , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Troponina I/sangue , Idoso , Ecocardiografia/métodos , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Cintilografia/métodos , Compostos Radiofarmacêuticos , Pirofosfato de Tecnécio Tc 99m
13.
Eur J Clin Microbiol Infect Dis ; 38(9): 1625-1631, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31218592

RESUMO

Labelled leucocyte scintigraphy (LS) is regarded as helpful when exploring bone and joint infections. The aim of this study was to evaluate the utility of LS for the diagnosis of chronic periprosthetic joint infections (PJIs) in patients exhibiting arthroplastic loosening. One hundred sixty-eight patients were referred to centres for treatment of complex PJI. One hundred fifty underwent LS using 99mTc-HMPAO (LLS); 18 also underwent anti-granulocyte scintigraphy (AGS) and 13 additional SPECT with tomodensitometry imaging (SPECT-CT). The LS results were compared with bone scan data. For all, the final diagnoses were determined microbiologically; perioperative samples were cultured. LS values were examined, as well as sensitivity by microorganism, anatomical sites, and injected activity. LS results were also evaluated according to the current use of antibiotics or not. The sensitivity, specificity, and positive predictive value of LLS were 72%, 60%, and 80%, respectively. LLS performed better than did AGS. SPECT-CT revealed the accurate locations of infections. The sensitivity of LS was not significantly affected by the causative pathogen or the injected activity. No correlation was evident between the current antibiotic treatment and the LS value. The test was more sensitive for knee (84%) than hip arthroplasty (57%) but was less specific for knee (52% vs. 75%). Sensitivity and specificity of LLS varied by the location of infection bone scan provide no additional value in PJI diagnosis. Current antibiotic treatment seems to have no influence on LS sensitivity as well as labelling leukocyte activity or pathogens responsible for chronic PJI.


Assuntos
Articulações/microbiologia , Leucócitos/imunologia , Infecções Relacionadas à Prótese/diagnóstico , Cintilografia/normas , Idoso , Feminino , Prótese de Quadril/microbiologia , Humanos , Prótese do Joelho/microbiologia , Masculino , Valor Preditivo dos Testes , Infecções Relacionadas à Prótese/imunologia , Infecções Relacionadas à Prótese/microbiologia , Cintilografia/métodos , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único
14.
Int. j. cardiovasc. sci. (Impr.) ; 32(3): 302-309, May-June 2019. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1002221

RESUMO

This paper is about the Guideline for Ventilation / Perfusion Scintigraphy. It has been developed by the Brazilian Society of Nuclear Medicine to be a best practices guide used in Nuclear Medicine. Its function is to be an educational tool to help the Nuclear Medicine Services in Brazil to guarantee a quality care to the patients


Assuntos
Humanos , Masculino , Feminino , Relação Ventilação-Perfusão , Guias como Assunto/normas , Artéria Pulmonar/patologia , Embolia Pulmonar/complicações , Embolia Pulmonar/diagnóstico por imagem , Diagnóstico por Imagem/métodos , Cintilografia/métodos , Medicina Nuclear/normas
15.
Vet Radiol Ultrasound ; 60(4): 432-446, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31050102

RESUMO

Ultrasound provides information on kidney morphology, but studies relating structural and functional abnormalities in chronic kidney disease (CKD) are lacking. The aim of this descriptive cross-sectional study was to compare individual kidney (IK) B-mode ultrasound abnormalities to IK glomerular filtration rate (GFR) estimated by scintigraphy normalized to plasma volume (PV) in dogs, to evaluate if ultrasonographic findings were associated with low IKGFR/PV. Eighty privately owned dogs with and without clinical suspicion of CKD were prospectively enrolled, and kidney ultrasound and IKGFR/PV were evaluated independently. Ultrasound images were assessed retrospectively for subjective abnormalities (shape, cortical, and medullary hyperechogenicity), and kidney size was measured. The normal IKGFR/PV cutoff was derived from dogs in the study group with no history and clinical signs of kidney disease and normal blood and urine results (n = 28) and was 16.84 mL/min/L. Kidneys were categorized into normal, mild, moderate, and severe ultrasound changes according to subjective ultrasound grades. Associations were found between low IKGFR/PV and abnormal kidney shape (P = .0004), cortical hyperechogenicity (P = .0008), medullary hyperechogenicity (P < .0001), and low kidney volume (P = .0092). Apart from the moderate and severe category comparison, IKGFR/PV value significantly decreased with increasing severity of category. The combination of ultrasonographic subjective abnormalities had a high sensitivity (93.8%) and moderate specificity (65.7%) for detecting low IKGFR/PV. Kidneys with normal IKGFR/PV had a low frequency of mild ultrasound changes. Findings indicate kidneys with increasing number and grade of subjective ultrasound abnormalities are more likely to have a lower IKGFR/PV.


Assuntos
Doenças do Cão/diagnóstico por imagem , Taxa de Filtração Glomerular/veterinária , Rim/diagnóstico por imagem , Cintilografia/veterinária , Ultrassonografia/veterinária , Animais , Estudos Transversais , Cães , Feminino , Taxa de Filtração Glomerular/fisiologia , Rim/anormalidades , Masculino , Cintilografia/métodos , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/fisiopatologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia/métodos
16.
Eur J Pharm Biopharm ; 140: 109-120, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31082509

RESUMO

Radionuclide molecular imaging is a promising tool that becomes increasingly important as targeted cancer therapies are developed. To ensure an effective treatment, a molecular stratification of the cancer is a necessity. To accomplish this, visualization of cancer associated molecular abnormalities in vivo by molecular imaging is the method of choice. ADAPTs, a novel type of small protein scaffold, have been utilized to select and develop high affinity binders to different proteinaceous targets. One of these binders, ADAPT6 selectively interacts with human epidermal growth factor 2 (HER2) with low nanomolar affinity and can therefore be used for its in vivo visualization. Molecular design and optimization of labeled anti-HER2 ADAPT has been explored in several earlier studies, showing that small changes in the scaffold affect the biodistribution of the domain. In this study, we evaluate how the biodistribution properties of ADAPT6 is affected by the commonly used maleimido derivatives of the macrocyclic chelators NOTA, NODAGA, DOTA and DOTAGA with the aim to select the best variants for SPECT and PET imaging. The different conjugates were labeled with 111In for SPECT and 68Ga for PET. The acquired data show that the combination of a radionuclide and a chelator for its conjugation has a strong influence on the uptake of ADAPT6 in normal tissues and thereby gives a significant variation in tumor-to-organ ratios. Hence, it was concluded that the best variant for SPECT imaging is 111In-(HE)3DANS-ADAPT6-GSSC-DOTA while the best variant for PET imaging is 68Ga-(HE)3DANS-ADAPT6-GSSC-NODAGA.


Assuntos
Quelantes/química , Radioisótopos de Gálio/química , Radioisótopos de Índio/química , Compostos Macrocíclicos/química , Proteínas/metabolismo , Cintilografia/métodos , Receptor ErbB-2/metabolismo , Linhagem Celular Tumoral , Humanos , Marcação por Isótopo/métodos , Imagem Molecular/métodos , Tomografia por Emissão de Pósitrons/métodos , Distribuição Tecidual/efeitos dos fármacos , Tomografia Computadorizada de Emissão de Fóton Único/métodos
17.
Graefes Arch Clin Exp Ophthalmol ; 257(7): 1535-1540, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31037489

RESUMO

PURPOSE: To evaluate the clinical usefulness of the dacryoscintigraphy in patients with nasolacrimal duct obstruction prior to endoscopic dacryocystorhinostomy. METHODS: One hundred thirty-five lacrimal views of endoscopic dacryocystorhinostomy (DCR) with a single surgeon for primary nasolacrimal duct obstruction (PANDO) were included. These were assigned into three groups according to the type of dacryoscintigraphy. Group 1 was a pre-sac obstruction pattern. Group 2 was an intra-sac obstruction pattern. Group 3 was post-sac obstruction pattern. Each group was evaluated for an anatomical and functional surgical success, presence of complications including granuloma, synechiae, and tube-induced inflammation at least 12 months after the surgery. RESULTS: Both anatomical and functional success rate showed no significant difference among the three groups (P = .297 and .472 linear by linear association). Functional failure rate (functional failure/total failure) also showed no clinically significant differences between groups. Logistic regression analysis was performed to determine the factors associated with functional success. There were no statistically significant factors in age, sex, scintigraphy type, pre-operative endoscopic grade, post-operative granuloma, and synechiae. CONCLUSION: In patients with nasolacrimal duct obstruction, preoperative evaluation of obstruction level using dacryoscintigraphy may be not useful for predicting the functional success of the endoscopic dacryocystorhinostomy.


Assuntos
Dacriocistorinostomia/métodos , Endoscopia/métodos , Aparelho Lacrimal/diagnóstico por imagem , Obstrução dos Ductos Lacrimais/diagnóstico , Ducto Nasolacrimal/diagnóstico por imagem , Cuidados Pré-Operatórios/métodos , Cintilografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Aparelho Lacrimal/cirurgia , Masculino , Pessoa de Meia-Idade , Ducto Nasolacrimal/cirurgia , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença
18.
Tumori ; 105(5): 394-403, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31041885

RESUMO

PURPOSE: To test ultra-low-dose computed tomography (ULDCT) scanning protocols for the detection of pulmonary nodules (PN). METHODS: A chest phantom containing 19 solid and 11 subsolid PNs was scanned on a third-generation dual-source computed tomography (CT) scanner. Five ULDCT scans (Sn100kVp and 120, 70, 50, 30, and 20 reference mAs, using tube current modulation), reconstructed with iterative reconstruction (IR) algorithm at strength levels 2, 3, 4, and 5, were compared with standard CT (120kVp, 150 reference mAs, using tube current modulation). PNs were subjectively assessed according to a 4-point scale: 0, nondetectable nodule; 1, detectable nodule, very unlikely to be correctly measured; 2, detectable nodule, likely to be correctly measured; 3, PN quality equal to standard of reference. PN scores were analysed according to the Lung Imaging Reporting and Data System (Lung-RADS), simulating detection of nodules at baseline and incidence screening round. RESULTS: For the baseline round, there were 17 Lung-RADS 2, 4 Lung-RADS 3, 8 Lung-RADS 4A, and 1 Lung-RADS 4B PNs. They were detectable in any ULDCT protocol, with the exception of 1 nondetectable part-solid nodule in 1 scanning protocol (120 reference mAs; IR strength: 3). For the incidence round, there were 4 Lung-RADS 2, 14 Lung-RADS 3, 2 Lung-RADS 4A, and 10 Lung-RADS 4B PNs. Ten were nondetectable in at least one ULDCT dataset; however, they were at least detectable in ULDCT with 70 reference mAs (IR strength: 4 and 5). CONCLUSIONS: ULDCT scanning protocols allowing the detection of PNs can be proposed for the purpose of lung cancer screening.


Assuntos
Neoplasias Pulmonares/diagnóstico , Nódulos Pulmonares Múltiplos/diagnóstico , Imagens de Fantasmas , Tomografia Computadorizada por Raios X/métodos , Detecção Precoce de Câncer , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/patologia , Doses de Radiação , Cintilografia/métodos
19.
Nuklearmedizin ; 58(3): 282-284, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31064028

RESUMO

Lymphatic mapping for identification and subsequent removal of the sentinel lymph node (SLN) is an established procedure in breast cancer and cutaneous melanoma to minimize the extent of surgery (and thus, associated morbidity), simplify histopathological processing and subsequently provide prognostic information and help choose the optimal patient management. Established methods for SLN mapping include visual identification of nodal staining after peritumoral injection of a (blue) dye or the use of lymphoscintigraphy with technetium-labelled nanocolloid. In experienced hands, success rates for both methods exceed 95 %, nonetheless in some patients they fail despite correct application and imaging techniques. Potential reasons for false-negative SLN detection rates -beyond poor tracer injection technique or imaging of the wrong nodal basin- include inadequate pathologic examination of the SLN or complete replacement of the SLN with neoplastic disease, causing the injected tracer to completely bypass the infiltrated node 1.Beyond colloid particles, the more specific receptor-targeting small molecule [99mTc]Tilmanocept has recently been approved for scintigraphic SLN detection. Tilmanocept, or mannosyl diethylene-triamine-pentaacetate (DTPA) dextran, has a small molecular size of approximately 7 nm and works via specific binding to the mannose receptor (CD206) 2. The mannose receptor is particularly overexpressed on macrophages and dendritic precursor cells within lymph nodes, thus uptake in lymph nodes is not dependent on particle size 2, 3. In pilot studies scintigraphic SLN detection with [99mTc]Tilmanocept was superior to dye staining 4. Given its beneficial properties, [99mTc]Tilmanocept might offer advantages over the alternatively used radiocolloids. We present four cases of [99mTc]Tilmanocept application after inconclusive or unsuccessful attempts of SLN detection using [99mTc]nanocolloid lymphoscintigraphy.


Assuntos
Neoplasias da Mama/diagnóstico , Dextranos/metabolismo , Linfocintigrafia/métodos , Mananas/metabolismo , Cintilografia/métodos , Compostos Radiofarmacêuticos/metabolismo , Agregado de Albumina Marcado com Tecnécio Tc 99m/metabolismo , Pentetato de Tecnécio Tc 99m/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Biópsia de Linfonodo Sentinela , Padrão de Cuidado , Pentetato de Tecnécio Tc 99m/metabolismo
20.
Technol Cancer Res Treat ; 18: 1533033819842586, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079574

RESUMO

BACKGROUND: Νeuroendocrine tumors of the lungs are rare arising in the thymus and gastro-entero-pancreatic tract and belonging to foregut of neuroendocrine tumors. The aim of the present prospective study was to estimate the potential impact of single-photon emission computed tomography somatostatin receptor scintigraphy using 99mTc-Tektrotyd on diagnosis, treatment response, and prognosis in patients with neuroendocrine tumors of the lungs. METHODS: Thirty-six patients with neuroendocrine tumors of the lungs were evaluated by using 99mTc-HYNIC-TOC scintigraphy. The scintigraphic results were compared to liver tissue uptake (Krenning score). Likewise, the functional imaging results were compared with biochemical indices including chromogranin A, neuroendocrine-specific enolase, and insulin-like growth factor 1 at the time of diagnosis (baseline) and disease progression. RESULTS: The number of somatostatin receptors, expressed with Krenning score, did not show any correlation with the survival of patients both at baseline ( P = .08) and at disease progression ( P = .24), and scintigraphy results did not relate significantly to progression-free survival. Comparing the results of 99mTc-HYNIC-TOC scintigraphy according to the response of patients in the initial treatment, a statistically significant negative correlation was observed both in the first and in the second scintigraphy with patients' response ( P = .001 and P < .001, respectively). The concentrations of biochemical markers were in accordance with scintigraphy results in the diagnosis. CONCLUSION: This study indicates that 99mTc-HYNIC-TOC scintigraphy appears to be a reliable, noninvasive technique for detection of primary neuroendocrine tumors and their locoregional or distant metastases, although it cannot be used as a neuroendocrine tumors of the lungs predictive technique.


Assuntos
Neoplasias Pulmonares/diagnóstico , Tumores Neuroendócrinos/diagnóstico , Octreotida/análogos & derivados , Compostos de Organotecnécio , Cintilografia , Idoso , Biomarcadores Tumorais , Progressão da Doença , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tumores Neuroendócrinos/sangue , Tumores Neuroendócrinos/mortalidade , Tumores Neuroendócrinos/terapia , Valor Preditivo dos Testes , Cintilografia/métodos , Resultado do Tratamento
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