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1.
Scanning ; 2022: 9640177, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35924105

RESUMO

Though artificial intelligence (AI) has been used in nuclear medicine for more than 50 years, more progress has been made in deep learning (DL) and machine learning (ML), which have driven the development of new AI abilities in the field. ANNs are used in both deep learning and machine learning in nuclear medicine. Alternatively, if 3D convolutional neural network (CNN) is used, the inputs may be the actual images that are being analyzed, rather than a set of inputs. In nuclear medicine, artificial intelligence reimagines and reengineers the field's therapeutic and scientific capabilities. Understanding the concepts of 3D CNN and U-Net in the context of nuclear medicine provides for a deeper engagement with clinical and research applications, as well as the ability to troubleshoot problems when they emerge. Business analytics, risk assessment, quality assurance, and basic classifications are all examples of simple ML applications. General nuclear medicine, SPECT, PET, MRI, and CT may benefit from more advanced DL applications for classification, detection, localization, segmentation, quantification, and radiomic feature extraction utilizing 3D CNNs. An ANN may be used to analyze a small dataset at the same time as traditional statistical methods, as well as bigger datasets. Nuclear medicine's clinical and research practices have been largely unaffected by the introduction of artificial intelligence (AI). Clinical and research landscapes have been fundamentally altered by the advent of 3D CNN and U-Net applications. Nuclear medicine professionals must now have at least an elementary understanding of AI principles such as neural networks (ANNs) and convolutional neural networks (CNNs).


Assuntos
Aprendizado Profundo , Medicina Nuclear , Inteligência Artificial , Imageamento por Ressonância Magnética , Redes Neurais de Computação
3.
J Nucl Med ; 63(8): 9N-20N, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35914822
4.
J Nucl Med ; 63(8): 19N-20N, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35914823
5.
J Nucl Med ; 63(8): 18N, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35914826
6.
J Nucl Med ; 63(8): 13N, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35914827
9.
J Nucl Med ; 63(8): 10N, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35914830
10.
Urologie ; 61(8): 869-878, 2022 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-35925295

RESUMO

The diagnostics and treatment of pediatric urology patients in the clinical routine can be extremely challenging. In contrast to adult patients, the main concerns in the diagnostics of congenital diseases are time consuming examinations and limited options in addition to the expectations of the parents. The exact knowledge of the diagnostic possibilities in association with the correct interpretation of the indications is essential. Simple processes can be much more time consuming because of a lack of compliance, especially in very young children. Sonography is considered the standard for imaging in pediatric urology. Profound knowledge of the embryonal development and also physiological processes throughout childhood contribute to making the correct diagnosis. This article deals with the possibilities of nuclear medicine diagnostics, advanced diagnostics in bladder voiding disorders and finally imaging diagnostics in the pediatric urological operating room.


Assuntos
Medicina Nuclear , Doenças da Bexiga Urinária , Transtornos Urinários , Urologia , Adulto , Criança , Pré-Escolar , Humanos , Salas Cirúrgicas , Bexiga Urinária/diagnóstico por imagem , Transtornos Urinários/diagnóstico
11.
Nucl Med Rev Cent East Eur ; 25(2): 142-147, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35929128

RESUMO

Amyloid transthyretin cardiomyopathy is a progressive disease that confers significant mortality. While it is relatively rare, the frequency of diagnoses has risen with the increased contribution of novel diagnostic approach over the last decade. Traditionally tissue biopsy was considered to be a gold standard for amyloidosis diagnosis. However, there are significant limitations in the wide application of this approach. A noninvasive imaging-based diagnostic algorithm has been substantially developed in recent years. Establishing radionuclide imaging standards may translate into a further enhancement of disease detection and improving prognosis in the group of patients. Therefore we present in the following document current evidence on the scintigraphic diagnosis of cardiac transthyretin amyloidosis. Moreover, we present standardized protocol for the acquisition and interpretation criteria in the scintigraphic evaluation of cardiac amyloidosis.


Assuntos
Neuropatias Amiloides Familiares , Medicina Nuclear , Neuropatias Amiloides Familiares/diagnóstico por imagem , Prova Pericial , Humanos , Polônia , Cintilografia
12.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 41(4): 223-230, jul. - ago. 2022. ilus, graf, tab
Artigo em Espanhol | IBECS | ID: ibc-ADZ-774

RESUMO

Objetivo: Conocer el estado actual de la técnica de localización radioguiada de lesiones no palpables de mama con o sin indicación de biopsia selectiva de ganglio centinela —ROLL, SNOLL y semillas de 125I— mediante la realización de una encuesta nacional elaborada por el Grupo de Trabajo de Cirugía Radioguiada (GTCRG) de la Sociedad Española de Medicina Nuclear e Imagen Molecular (SEMNIM). Material y métodos: En octubre del 2020 se envió la encuesta, en formato digital, a los distintos servicios de Medicina Nuclear de nuestra geografía. Se dio un tiempo de respuesta de 2meses con prórroga de 15 días. Se ha obtenido el número de procedimientos ROLL/SNOLL de cada centro y la metodología utilizada, recogiendo importantes detalles técnicos. Además, se ha incluido un apartado específico sobre las semillas de 125I. Los resultados se volcaron de forma automática en una hoja de cálculo Excel 2007 para su posterior análisis con el mismo programa. Resultados: La encuesta fue contestada por 55 centros; 21 utilizan arpón mientras que los 34 restantes emplean distintas técnicas de cirugía radioguiada (CRG) para la localización de lesiones no palpables de mama, desglosando los resultados en 13apartados. La dosis de trazador habitualmente utilizada es de 111 MBq para la técnica ROLL y de 222 MBq para la técnica SNOLL, con un volumen de 0,2ml. El protocolo más habitual es el de 2días. El 26% de los centros que realiza CRG utiliza semillas de 125I tanto para la detección de lesiones mamarias como de ganglios sospechosos/patológicos, siendo el tiempo entre la implantación y la extirpación es de unos 3 días, con posterior control radiológico en la mayoría de los casos. Conclusión: La encuesta pone de manifiesto la relevancia de la cirugía radioguiada en el manejo de los pacientes con cáncer de mama en las diferentes etapas de la enfermedad, con disparidad en la implementación de las nuevas técnicas y herramientas (AU)


Objective: To know the current status of the technique of radioguided localisation of non-palpable breast lesions with or without indication for selective sentinel node biopsy -ROLL, SNOLL and 125I seeds- by conducting a national survey developed by the Working Group on Radioguided Surgery (GTCRG) of the Spanish Society of Nuclear Medicine and Molecular Imaging (SEMNIM). Material and methods: In October 2020, the form was sent in digital format to the different nuclear medicine services in Spain. A response time of 2months with an overtime of 15 days was given. The number of ROLL/SNOLL procedures in each centre and the methodology used were obtained, including important technical details. In addition, a specific section on 125I seeds was included. The results were automatically downloaded into an Excel 2007 spreadsheet for subsequent analysis with the same program. Results: The survey was answered by 55 centres; 21 use wire-guided localisation while the remaining 34 use different radioguided surgery techniques (RGS) for the localisation of non-palpable breast lesions, with the results itemized into thirteen sections. The commonly used tracer dose is 111 MBq for the ROLL technique and 222 MBq for the SNOLL technique, with a volume of 0.2ml. The most common protocol is the two-day protocol. 26% of centres performing CRG use 125I seeds for both breast lesion and suspicious/pathological node detection, with the time between implantation and removal being about 3 days, with subsequent radiological control in most cases. Conclusion: The survey shows the relevance of radioguided surgery in the management of breast cancer patients at different stages of the disease, with disparity in the implementation of new techniques and tools, which responds to the multiple healthcare realities of Nuclear Medicine services (AU)


Assuntos
Humanos , Feminino , Neoplasias da Mama/cirurgia , Neoplasias da Mama/diagnóstico , Medicina Nuclear , Biópsia de Linfonodo Sentinela , Cirurgia Assistida por Computador , Pesquisas sobre Atenção à Saúde , Radioisótopos do Iodo , Imagem Molecular , Sociedades Médicas , Espanha
13.
J Radiol Prot ; 42(3)2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35850112

RESUMO

National diagnostic reference levels (DRLs) are essential tools for optimizing protocols and protecting patients from an unjustified radiation exposure. The aim of this study was to conduct a nationwide survey of adult patient doses received from nuclear medicine (NM) procedures and to update national DRL (NDRL) values for most common procedures. Data on the radioactivity administered to standard adult patients were collected from all Lithuanian hospitals using NM applications in practice, between 2017 and 2022. Twelve of the most commonly performed NM diagnostic procedures: myocardial perfusion scintigraphy (two parts), thyroid scintigraphy, lung perfusion scintigraphy, bone scintigraphy, dynamic renal scintigraphy (divided into two procedures), parathyroid scintigraphy, hepatobiliary scintigraphy, lymphoscintigraphy, neuroendocrine tumour scan, and oncology positron emission tomography/computed tomography (PET/CT) imaging were included. The 75th percentile of the dose distribution was estimated for establishing NDRLs. During the data collection period, the NM imaging equipment was upgraded. The procedures were completed with 12 single photon emission computed tomography (SPECT) and SPECT/CT gamma cameras (2 with cadmium zinc telluride (CZT) detectors), 2 cardiac-centred gamma cameras with CZT detectors, and 2 PET/CT scanners. Data were collected on 7979 activities administered to the patients. For each procedure, depending on its frequency, 50-580 administered radiopharmaceutical activities were selected. Based on the collected data, NDRLs were updated in 2021 for three procedures. A large part of the procedures were performed with scanners manufactured between 2008 and 2011. In the past few years, the main Lithuanian hospitals that provide NM services have updated their SPECT/CT systems. In the future, the data collection process should be continued in order to reassess DRLs with respect to new scanning systems (e.g. with CZT detectors and newer PET/CT technology). Variations in the prescribed radiopharmaceutical activities showed that optimization and harmonization procedures may be performed in some hospitals.


Assuntos
Medicina Nuclear , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adulto , Cádmio , Humanos , Doses de Radiação , Cintilografia , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X
16.
J Appl Clin Med Phys ; 23(8): e13713, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35775691

RESUMO

The most recent statement published by the International Commission on Radiological Protection describes a reduction in the maximum allowable occupational eye lens dose from 150 to 20 mSv/year (averaged over 5-year periods). Exposing the eye lens to radiation is a concern for nuclear medicine staff who handle radionuclide tracers with various levels of photon energy. This study aimed to define the optimal dosimeter and means of measuring the amount of exposure to which the eye lens is exposed during a routine nuclear medicine practice. A RANDO human phantom attached to Glass Badge and Luminess Badge for body or neck, DOSIRIS and VISION for eyes, and nanoDot for body, neck, and eyes was exposed to 99m Tc, 123 I, and 18 F radionuclides. Sealed syringe sources of each radionuclide were positioned 30 cm from the abdomen of the phantom. Estimated exposure based on measurement conditions (i.e., air kerma rate constants, conversion coefficient, distance, activity, and exposure time) was compared measured dose equivalent of each dosimeter. Differences in body, neck, and eye lens dosimeters were statistically analyzed. The 10-mm dose equivalent significantly differed between the Glass Badge and Luminess Badge for the neck, but these were almost equivalent at the body. The 0.07-mm dose equivalent for the nanoDot dosimeters was greatly overestimated compared to the estimated exposure of 99m Tc and 123 I radionuclides. Measured dose equivalents of exposure significantly differed between the body and eye lens dosimeters with respect to 18 F. Although accurately measuring radiation exposure to the eye lenses of nuclear medicine staff is conventionally monitored using dosimeters worn on the chest or abdomen, eye lens dosimeters that provide a 3-mm dose equivalent near the eye would be a more reliable means of assessing radiation doses in the mixed radiation environment of nuclear medicine.


Assuntos
Cristalino , Medicina Nuclear , Exposição Ocupacional , Exposição à Radiação , Proteção Radiológica , Humanos , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Doses de Radiação , Exposição à Radiação/análise , Exposição à Radiação/prevenção & controle , Proteção Radiológica/métodos , Radioisótopos
18.
Bioconjug Chem ; 33(7): 1422-1436, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35801668

RESUMO

Auger electron therapy exploits the cytotoxicity of low-energy electrons emitted during radioactive decay that travel very short distances (typically <1 µm). 201Tl, with a half-life of 73 h, emits ∼37 Auger and other secondary electrons per decay and can be tracked in vivo as its gamma emissions enable SPECT imaging. Despite the useful nuclear properties of 201Tl, satisfactory bifunctional chelators to incorporate it into bioconjugates for molecular targeting have not been developed. H4pypa, H5decapa, H4neunpa-NH2, and H4noneunpa are multidentate N- and O-donor chelators that have previously been shown to have high affinity for 111In, 177Lu, and 89Zr. Herein, we report the synthesis and serum stability of [nat/201Tl]Tl3+ complexes with H4pypa, H5decapa, H4neunpa-NH2, and H4noneunpa. All ligands quickly and efficiently formed complexes with [201Tl]Tl3+ that gave simple single-peak radiochromatograms and showed greatly improved serum stability compared to DOTA and DTPA. [natTl]Tl-pypa was further characterized using nuclear magnetic resonance spectroscopy (NMR), mass spectroscopy (MS), and X-ray crystallography, showing evidence of the proton-dependent presence of a nine-coordinate complex and an eight-coordinate complex with a pendant carboxylic acid group. A prostate-specific membrane antigen (PSMA)-targeting bioconjugate of H4pypa was synthesized and radiolabeled. The uptake of [201Tl]Tl-pypa-PSMA in DU145 PSMA-positive and PSMA-negative prostate cancer cells was evaluated in vitro and showed evidence of bioreductive release of 201Tl and cellular uptake characteristic of unchelated [201Tl]TlCl. SPECT/CT imaging was used to probe the in vivo biodistribution and stability of [201Tl]Tl-pypa-PSMA. In healthy animals, [201Tl]Tl-pypa-PSMA did not show the myocardial uptake that is characteristic of unchelated 201Tl. In mice bearing DU145 PSMA-positive and PSMA-negative prostate cancer xenografts, the uptake of [201Tl]Tl-pypa-PSMA in DU145 PSMA-positive tumors was higher than that in DU145 PSMA-negative tumors but insufficient for useful tumor targeting. We conclude that H4pypa and related ligands represent an advance compared to conventional radiometal chelators such as DOTA and DTPA for Tl3+ chelation but do not resist dissociation for long periods in the biological environment due to vulnerability to reduction of Tl3+ and subsequent release of Tl+. However, this is the first report describing the incorporation of [201Tl]Tl3+ into a chelator-peptide bioconjugate and represents a significant advance in the field of 201Tl-based radiopharmaceuticals. The design of the next generation of chelators must include features to mitigate this susceptibility to bioreduction, which does not arise for other trivalent heavy radiometals.


Assuntos
Medicina Nuclear , Neoplasias da Próstata , Animais , Antígenos de Superfície/metabolismo , Linhagem Celular Tumoral , Quelantes/química , Glutamato Carboxipeptidase II/metabolismo , Humanos , Masculino , Camundongos , Ácido Pentético , Neoplasias da Próstata/patologia , Compostos Radiofarmacêuticos/química , Radioisótopos de Tálio , Distribuição Tecidual
19.
Ann Nucl Med ; 36(8): 695-709, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35794455

RESUMO

In this manuscript, we present the guideline for use of meta-[211At] astatobenzylguanidine ([211At] MABG), a newly introduced alpha emitting radiopharmaceutical to the up-coming World's first clinical trial for targeted alpha therapy (TAT) at Fukushima Medical University in Japan, focusing on radiation safety issues in Japan. This guideline was prepared based on a study supported by the Ministry of Health, Labour, and Welfare, and approved by the Japanese Society of Nuclear Medicine on Oct. 5th, 2021. The study showed that patients receiving [211At] MABG do not need to be admitted to a radiotherapy room and that TAT using [211At] MABG is possible on an outpatient basis. The radiation exposure from the patient is within the safety standards of the ICRP and IAEA recommendations for the general public and caregivers or patient's family members. In this guideline, the following contents are also included: precautions for patients and their families, safety management associated with the use of [211At] MABG, education and training, and disposal of medical radioactive contaminants. TAT using [211At] MABG in Japan should be carried out according to this guideline. Although this guideline is based on the medical environment and laws and regulations in Japan, the issues for radiation protection and evaluation methodology presented in this guideline are useful and internationally acceptable as well.


Assuntos
Guanidinas , Medicina Nuclear , Guanidinas/uso terapêutico , Humanos , Injeções , Compostos Radiofarmacêuticos/efeitos adversos
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