Frontiers in Nuclear Medicine最新文献

{"title":"First-in-human infection imaging with 89Zr-labelled leukocytes and comparison of scan quality with [99mTc]Tc-HMPAO-labelled leukocytes","authors":"Maryke Kahts, Beverley Summers, Akhona Nkokheli Ndlela, A. Gutta, Phumudzo Nemutaduni, Andrew More, Aman Parsoo, T. Ebenhan, J. Zeevaart, Omer Aras, M. Sathekge","doi":"10.3389/fnume.2024.1426650","DOIUrl":"https://doi.org/10.3389/fnume.2024.1426650","url":null,"abstract":"Nuclear medicine infection imaging is routinely performed with the use of leukocytes radiolabelled with technetium-99m hexamethylpropyleneamine oxime ([99mTc]Tc-HMPAO) and single-photon emission computed tomography (SPECT). Positron emission tomography (PET) is more sensitive than SPECT and results in higher-quality images. Zirconium-89 (89Zr) is a positron emitter with a half-life of 78.4 h, which translates to the biological half-life and slow biodistribution of intact cells and allows delayed PET imaging for more accurate biodistribution of the labelled leukocytes to infection foci. A first-in-human study with [89Zr]Zr-oxine-leukocytes in four healthy volunteers was reported in 2022. Our first-in-human study utilising the cell surface labelling approach aimed to image infection in patients with the use of 89Zr-labelled leukocytes, using p-isothiocyanatobenzyl-desferrioxamine B (Df-Bz-NCS) as a bifunctional chelating agent, and to compare the scan quality and biodistribution of [89Zr]Zr-Df-Bz-NCS-labelled leukocytes on PET images to SPECT images obtained with [99mTc]Tc-HMPAO-labelled leukocytes.Leukocytes were isolated from whole-blood samples of eight patients with clinically and/or radiologically confirmed infection. Isolated leukocytes were labelled with [99mTc]Tc-HMPAO according to standardised methods, and [89Zr]Zr-Df-Bz-NCS according to our previously published radiolabelling method. Whole-body SPECT imaging was performed 2 and 18 h post injection of [99mTc]Tc-HMPAO-labelled leukocytes, and whole-body PET/CT was performed 3 and 24 h post injection of [89Zr]Zr-Df-Bz-NCS-labelled leukocytes in seven patients.Successful [89Zr]Zr-Df-Bz-NCS-leukocyte labelling was achieved. High labelling efficiencies were obtained (81.7% ± 3.6%; n = 8). A mean high viability of [89Zr]Zr-Df-Bz-NCS-labelled leukocytes was observed (88.98% ± 12.51%). The [89Zr]Zr-Df-Bz-NCS-leukocyte labelling efficiency was not significantly affected by the white blood cell count of the patient. The performance of [99mTc]Tc-HMPAO- and [89Zr]Zr-Df-Bz-NCS-labelled leukocytes, in terms of the ability to accurately detect infection, were similar in two out of seven patients, and [99mTc]Tc-HMPAO-labelled leukocytes outperformed [89Zr]Zr-Df-Bz-NCS-labelled leukocytes in one patient with femoral osteomyelitis. However, in two cases of pulmonary pathology, [89Zr]Zr-Df-Bz-NCS-labelled leukocytes demonstrated improved pathological uptake. No skeletal activity was observed in any of the patients imaged with [89Zr]Zr-Df-Bz-NCS-labelled leukocytes, illustrating the in vivo stability of the radiolabel.Although the [89Zr]Zr-Df-Bz-NCS-leukocyte labelling aspect of this study was noteworthy, infection imaging did not yield convincingly positive results due to the pulmonary trapping of intravenously administered [89Zr]Zr-Df-Bz-NCS-labelled leukocytes.","PeriodicalId":505895,"journal":{"name":"Frontiers in Nuclear Medicine","volume":"16 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141815657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance of simplified methods for quantification of [18F]NaF uptake in fibrodysplasia ossificans progressiva","authors":"R. D. de Ruiter, Esmée Botman, B. Teunissen, Adriaan A. Lammertsma, Ronald Boellaard, Pieter G. Raijmakers, Lothar A. Schwarte, Jakko A. Nieuwenhuijzen, Dinko Gonzalez Trotter, E. M. Eekhoff, M. Yaqub","doi":"10.3389/fnume.2024.1406947","DOIUrl":"https://doi.org/10.3389/fnume.2024.1406947","url":null,"abstract":"Fibrodysplasia Ossificans Progressiva (FOP) is a rare, genetic disease in which heterotopic bone is formed in muscles, tendons and ligaments throughout the body. Disease progression is variable over time and between individuals. 18F-fluoride uptake in newly formed bone can be evaluated using [18F]NaF (i.e., sodiumfluoride) PET/CT, identifying active areas of bone formation in FOP. The purpose of this study was to assess the performance of various semi-quantitative methods with full kinetic analysis.Seven patients (age range: 20–31 years) with FOP underwent dynamic [18F]NaF scans at baseline and after one year. [18F]NaF uptake was measured in aorta descendens, vertebrae, heterotopic bone lesions and metabolically active regions on PET, and quantified using nonlinear regression (NLR) analysis together with standardized uptake value (SUV) and target-to-blood ratio (TBR). SUV was on measured the 40–45 min frame of the dynamic sequence (SUV40–45) and on the subsequent static sweep (SUVStatic). Correlations between and SUV40–45 and NLR-derived Ki were comparable when normalized to body weight (r = 0.81, 95% CI 0.64–0.90), lean body mass (r = 0.79, 95% CI 0.61–0.89) and body surface area (r = 0.84, 95% CI 0.70–0.92). Correlation between TBR40–45 and NLR-derived Ki (r = 0.92, 95% CI 0.85–0.96) was higher than for SUV40–45. Correlation between TBR40–45 and NLR-derived Ki was similar at baseline and after one year (r = 0.93 and 0.94). The change in TBR40–45 between baseline measurement and after one year correlated best with the change in NLR-derived Ki in the PET-active lesions (r = 0.87).The present data supports the use of TBR for assessing fluoride uptake in PET-active lesions in FOP.Sub-study of the Lumina-1 trial (clinicaltrials.gov, NCT03188666, registered 13-06-2017).","PeriodicalId":505895,"journal":{"name":"Frontiers in Nuclear Medicine","volume":"6 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141814761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Case report: When infection lurks behind malignancy: a unique case of primary bone lymphoma mimicking infectious process in the spine","authors":"Ayoub Jaafari, Ornella Rizzo, Sohaïb Mansour, Anas Chbabou, A. Trépant, Rachid Attou, Celine Mathey","doi":"10.3389/fnume.2024.1402552","DOIUrl":"https://doi.org/10.3389/fnume.2024.1402552","url":null,"abstract":"Primary bone lymphoma of the spine (PBL) is a rare entity that may be misdiagnosed due to its atypical location and clinical and imaging features mimicking certain pathologies as infectious processes, which complicates and delays diagnosis. Our case reports a patient in her sixties who had been suffering from chronic low back pain for a year, and had gradually started to develop cruralgia. She underwent a blood sample, magnetic resonance imaging (MRI), and positron emission tomography (18F-FDG-PET/CT) which revealed inflammatory syndrome, and an image of spondylodiscitis of the lumbar spine associated with a morphological and metabolical widespread invasion posteriorly suggesting epiduritis. No other lesions were found on the rest of the body. Neurosurgical management was performed and a biopsy was made. Histological results showed aggressive and diffuse large B-cell lymphoma, suggesting a diagnosis of PBL. This case highlights the first case of spondylodiscitis mimicking PBL in the lumbar spine, the intricacies of the diagnostic work-up, and the complexity of discriminating with an infectious process in the spine, as both have a similar, non-specific clinical presentation, while morphological and metabolic findings can be alike.","PeriodicalId":505895,"journal":{"name":"Frontiers in Nuclear Medicine","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141646033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"QUALIPAED—A retrospective quality control study evaluating pediatric long axial field-of-view low-dose FDG-PET/CT","authors":"Sabrina Honoré d’Este, F. L. Andersen, C. Schulze, E. Saxtoft, B. M. Fischer, K. F. Andersen","doi":"10.3389/fnume.2024.1398773","DOIUrl":"https://doi.org/10.3389/fnume.2024.1398773","url":null,"abstract":"Pediatric patients have an increased risk of radiation-induced malignancies due to their ongoing development and long remaining life span. Thus, optimization of PET protocols is an important task in pediatric nuclear medicine. Long axial field-of-view (LAFOV) PET/CT has shown a significant increase in sensitivity, which provides an ideal opportunity for reduction of injected tracer activity in the pediatric population. In this study we aim to evaluate the clinical performance of a 2-[18F]FDG-tracer reduction from 3 MBq/kg to 1.5 MBq/kg on the Biograph Vision Quadra LAFOV PET/CT.The first 50 pediatric patients referred for clinical whole-body PET/CT with 1.5 MBq/kg 2-[18F]FDG, were included. A standard pediatric protocol was applied. Five reconstructions were created with various time, filter and iteration settings. Image noise was computed as coefficient-of-variance (COV = SD/mean standardized-uptake-value) calculated from a spherical 20–50 mm (diameter) liver volume-of-interest. Sets of reconstructions were reviewed by one nuclear medicine physicians, who reported image lesions on a pre-defined list of sites. Paired comparison analysis was performed with significance at PB < 0.05 (Bonferroni corrected).All reconstructions, except one, achieved a COVmean (0.08–0.15) equal to or lower than current clinical acceptable values (COVref ≤ 0.15). Image noise significantly improved with increasing acquisition time, lowering iterations (i) from 6i to 4i (both with five subsets) and when applying a 2 mm Gauss filter (PB < 0.001). Significant difference in lesion detection was seen from 150s to 300s and from 150s to 600s (PB = 0.006–0.007). 99% of all lesions rated as malignant could be found on the 150s reconstruction, while 100% was found on the 300s, when compared to the 600s reconstruction.Injected activity and scan time can be reduced to 1.5 MBq/kg 2-[18F]FDG with 5 min acquisition time on LAFOV PET/CT, while maintaining clinical performance in the pediatric population. These results can help limit radiation exposure to patients and personnel as well as shorten total scan time, which can help increase patient comfort, lessen the need for sedation and provide individually tailored scans.","PeriodicalId":505895,"journal":{"name":"Frontiers in Nuclear Medicine","volume":"61 36","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141347086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial: Women in radionuclide therapy: 2023","authors":"E. Lopci, Federica Matteucci","doi":"10.3389/fnume.2024.1411878","DOIUrl":"https://doi.org/10.3389/fnume.2024.1411878","url":null,"abstract":"","PeriodicalId":505895,"journal":{"name":"Frontiers in Nuclear Medicine","volume":" 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140997701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single-voxel delay map from long-axial field-of-view PET scans","authors":"Frederik Bay Nielsen, Ulrich Lindberg, Heloisa N. Bordallo, C. B. Johnbeck, Ian Law, B. M. Fischer, F. L. Andersen, T. L. Andersen","doi":"10.3389/fnume.2024.1360326","DOIUrl":"https://doi.org/10.3389/fnume.2024.1360326","url":null,"abstract":"We present an algorithm to estimate the delay between a tissue time activity curve and a blood input curve at a single-voxel level tested on whole-body data from a long-axial field-of-view scanner with tracers of different noise characteristics.Whole-body scans of 15 patients divided equally among three tracers: [15O]H2O, [18F]FDG and [64Cu]Cu-DOTATATE, were used in development and testing of the algorithm. Delay time were estimated by fitting the cumulatively summed input function and tissue time activity curve with special considerations for noise. To evaluate the performance of the algorithm, it was compared against two other algorithms also commonly applied in delay estimation, name cross-correlation and a one-tissue compartment model with incorporated delay. All algorithms were tested on both synthetic time activity curves produced with the one-tissue compartment model with increasing levels of noise and delays between the tissue activity curve and the blood input curve. Whole-body delay maps were also calculated for each of the three tracers with data acquired on a long-axial field-of-view scanner with high time resolution.Our proposed model performs better for low signal-to-noise ratio time activity curves compared to both cross-correlation and the one-tissue compartment models for non-[15O]H2O tracers. Testing on synthetically produced time activity curves it displays only a small and even residual delay, while the one-tissue compartment model with included delay showed varying residual delays.The algorithm is robust to noise and proves applicable on a range of tracers as tested on [15O]H2O, [18F]FDG and [64Cu]Cu-DOTATATE, and hence is a viable option offering the ability for delay correction across various organs and tracers in use with kinetic modeling.","PeriodicalId":505895,"journal":{"name":"Frontiers in Nuclear Medicine","volume":" 16","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140683553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial: Bridging the gap to molecular imaging and theranostics","authors":"Stuart More, Mike Sathekge, Vikas Prasad","doi":"10.3389/fnume.2024.1385097","DOIUrl":"https://doi.org/10.3389/fnume.2024.1385097","url":null,"abstract":"","PeriodicalId":505895,"journal":{"name":"Frontiers in Nuclear Medicine","volume":"8 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140713415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep learning derived input function in dynamic [18F]FDG PET imaging of mice","authors":"Samuel Kuttner, L. Luppino, L. Convert, O. Sarrhini, Roger Lecomte, Michael C. Kampffmeyer, R. Sundset, Robert Jenssen","doi":"10.3389/fnume.2024.1372379","DOIUrl":"https://doi.org/10.3389/fnume.2024.1372379","url":null,"abstract":"Dynamic positron emission tomography and kinetic modeling play a critical role in tracer development research using small animals. Kinetic modeling from dynamic PET imaging requires accurate knowledge of an input function, ideally determined through arterial blood sampling. Arterial cannulation in mice, however, requires complex, time-consuming and terminal surgery, meaning that longitudinal studies are impossible. The aim of the current work was to develop and evaluate a non-invasive, deep learning based prediction model (DLIF), that directly takes the PET data as input to predict a usable input function. We first trained and evaluated the DLIF model on 68 [18F]Fluorodeoxyglucose mouse scans with image-derived targets using cross validation. Subsequently, we evaluated the performance of a trained DLIF model on an external dataset consisting of 8 mouse scans where the input function was measured by continuous arterial blood sampling. The results showed that the predicted DLIF and image-derived targets were similar, and the net influx rate constants following from Patlak modeling using DLIF as input function were strongly correlated to the corresponding values obtained using the image-derived input function. There were somewhat larger discrepancies when evaluating the model on the external dataset, which could be attributed to systematic differences in the experimental setup between the two datasets. In conclusion, our non-invasive DLIF prediction method may be a viable alternative to arterial blood sampling in small animal [18F]FDG imaging. With further validation, DLIF could overcome the need for arterial cannulation and allow fully quantitative and longitudinal experiments in PET imaging studies of mice.","PeriodicalId":505895,"journal":{"name":"Frontiers in Nuclear Medicine","volume":"25 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140715668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep learned triple-tracer multiplexed PET myocardial image separation","authors":"B. Pan, P. Marsden, A. J. Reader","doi":"10.3389/fnume.2024.1379647","DOIUrl":"https://doi.org/10.3389/fnume.2024.1379647","url":null,"abstract":"In multiplexed positron emission tomography (mPET) imaging, physiological and pathological information from different radiotracers can be observed simultaneously in a single dynamic PET scan. The separation of mPET signals within a single PET scan is challenging due to the fact that the PET scanner measures the sum of the PET signals of all the tracers. The conventional multi-tracer compartment modeling method (MTCM) requires staggered injections and assumes that the arterial input functions (AIFs) of each tracer are known.In this work, we propose a deep learning-based method to separate triple-tracer PET images without explicitly knowing the AIFs. Dynamic triple-tracer noisy MLEM reconstruction was used as the network input and dynamic single-tracer noisy MLEM reconstructions were used as the training labels.A simulation study was performed to evaluate the performance of the proposed framework on triple-tracer ([18F]FDG+82Rb+[94mTc]sestamibi) PET myocardial imaging. The results show that the proposed methodology substantially reduced the noise level compared to the results obtained from single-tracer imaging. Additionally, it achieved lower bias and standard deviation in the separated single-tracer images compared to the MTCM-based method at both the voxel and ROI levels.As compared to the MTCM separation, the proposed method uses spatiotemporal information for separation, which enhances the separation performance at both the voxel and ROI levels. The simulation study also indicates the feasibility and potential of the proposed DL-based method for the application to pre-clinical and clinical studies.","PeriodicalId":505895,"journal":{"name":"Frontiers in Nuclear Medicine","volume":"12 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140716108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Immunological effects of radiopharmaceutical therapy","authors":"Amanda G. Shea, Malick Bio Idrissou, Ana Isabel Torres, Tessa Chen, Reiner Hernandez, Zachary S Morris, Quaovi H. Sodji","doi":"10.3389/fnume.2024.1331364","DOIUrl":"https://doi.org/10.3389/fnume.2024.1331364","url":null,"abstract":"Radiation therapy (RT) is a pillar of cancer therapy used in more than half of all cancer patients. Clinically, RT is mostly delivered as external beam radiation therapy (EBRT). However, the scope of EBRT is limited in the metastatic setting when all sites of disease need to be irradiated. Such limitation is attributed to radiation-induced toxicities including bone marrow and hematologic toxicities, ensuing from a large EBRT field. Radiopharmaceutical therapy (RPT) has emerged as an alternative to EBRT for the irradiation of all sites of metastatic disease. While RPT can reduce tumor burden, it can also impact the immune system and anti-tumor immunity. Understanding these effects is crucial for predicting and managing treatment-related hematological toxicities and optimizing their integration with other therapeutic modalities such as immunotherapies. Herein, we review the immunomodulatory effects of α- and β-particle emitter-based RPT on various immune cell lines including CD8+ and CD4+ T cells, natural killer (NK) cells, and regulatory T (Treg) cells. We briefly discuss Auger electron-emitter (AEE) based RPT and lastly, we highlight the combination of RPT with immune checkpoint inhibitors, which may offer potential therapeutic synergies for patients with metastatic cancers.","PeriodicalId":505895,"journal":{"name":"Frontiers in Nuclear Medicine","volume":"8 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140741254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}