Frontiers in nuclear medicine (Lausanne, Switzerland)最新文献

{"title":"Emotional stress during the COVID-19 lockdown: how negative X/Twitter posts correlated with changes in the brain's fear network.","authors":"Eric Guedj, Jacques-Yves Campion, Tatiana Horowitz, Fanny Barthélémy, Stéphanie Khalfa, Wissam El-Hage","doi":"10.3389/fnume.2025.1575026","DOIUrl":"10.3389/fnume.2025.1575026","url":null,"abstract":"<p><strong>Introduction: </strong>The COVID-19 pandemic has profoundly affected mental health, with lockdown periods particularly exacerbating negative emotions such as fear, sadness, and uncertainty. This study examines brain metabolic changes associated with the psychological context of the first French COVID-19 lockdown in vulnerable individuals.</p><p><strong>Methods: </strong>As a proxy measure of the psychological context, we used a composite negative-emotion score derived from an open-source X/Twitter dataset (\"The First French COVID-19 Lockdown Twitter Dataset\"), designed to capture public sentiment over the 55-day lockdown. This score was day-by-day correlated with whole-brain voxel-based [18F]FDG PET imaging in 95 patients with neurological conditions, using statistical parametric mapping (SPM) (<i>p</i>-voxel < 0.001, <i>k</i> > 108).</p><p><strong>Results: </strong>A significant negative correlation was found between daily negative-emotion scores and metabolism in the right ventromedial prefrontal cortex (vmPFC) and anterior cingulate cortex (ACC), key regions of the brain's fear circuit. Inter-regional correlation analysis (IRCA) of metabolic connectivity from the right vmPFC/ACC further revealed a right limbic-dominant network including the amygdala, hippocampus, thalamus, and basal ganglia.</p><p><strong>Discussion: </strong>These findings highlight the sensitivity of the right vmPFC/ACC to societal emotional stressors, suggesting a potential cerebral substrate for the increase in psychological and psychiatric disorders observed during the pandemic. Further research is needed to validate these results in larger populations and to explore their longitudinal implications, to better understand the neurological impact of collective stress.</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":"5 ","pages":"1575026"},"PeriodicalIF":0.0,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12186706/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144487319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating image-derived input functions for cerebral [¹⁸F]MC225 PET studies.","authors":"Giordana Salvi de Souza, Pascalle Mossel, Joost F Somsen, Laura Providência, Anna L Bartels, Antoon T M Willemsen, Rudi A J O Dierckx, Cristiane R G Furini, Adriaan A Lammertsma, Charalampos Tsoumpas, Gert Luurtsema","doi":"10.3389/fnume.2025.1597902","DOIUrl":"10.3389/fnume.2025.1597902","url":null,"abstract":"<p><p>Kinetic modelling of brain PET data is crucial for estimating quantitative biological parameters, traditionally requiring arterial sampling. This study evaluated whether arterial samples could be omitted to estimate the image-derived input function (IDIF) using a long axial field-of-view PET scanner. The use of internal carotid arteries (ICA) for IDIF estimation, along with venous samples for plasma-to-whole blood ratios and plasma parent fractions, was also assessed. Six healthy volunteers underwent [¹⁸F]MC225 scans with manual arterial sampling. IDIFs were derived from the aortic arch (IDIF_AA) and calibrated using manual arterial samples (IDIF_{AA_CAL}). ICA-derived IDIF was also calibrated (IDIF_{CA_CAL}) and compared to IDIF_{AA_CAL}. In a separate group of six volunteers, venous and arterial samples were collected to evaluate plasma-to-whole blood ratios, plasma parent fractions, and IDIF calibration (IDIF_{CA_CAL_VEN}). Volume of distribution (V_T) of different brain regions was estimated for all IDIFs techniques, corrected for plasma-to-whole blood ratio and plasma parent fraction (IDIF_AA,P, IDIF_{AA_CAL,P}, IDIF_{ICA_CAL,P} and IDIF_{ICA_CAL_VEN_P}). Our findings revealed discrepancies between IDIF_AA and arterial samples, highlighting the importance of calibration. The differences between IDIF_AA,P and IDIF_{AA_CAL,P} were 9.2% for area under the curve and 4.0% for brain V_T. IDIF_{ICA_CAL,P} showed strong agreement with IDIF_{A_CAL,P}, with 1.2% V_T difference. Venous sampling showed consistent agreement with arterial sampling for plasma parameters but was unreliable for IDIF calibration, leading to 39% V_T differences. This study emphasises that arterial samples are still required for IDIF calibration and reliable V_T estimation for [¹⁸F]MC225 PET tracer. ICA-derived IDIF, when calibrated, provides reliable V_T estimates. Venous sampling is a potential alternative for estimating plasma parameters, but it is unsuitable for IDIF calibration.</p><p><strong>Trial registry: </strong>NCT05618119 (clinicaltrials.gov/study/NCT05618119).</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":"5 ","pages":"1597902"},"PeriodicalIF":0.0,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12176838/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144334576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"¹⁸F-NaF PET/CT identifies muscular and subcutaneous calcifications in both dermatomyositis- and systemic sclerosis-related calcinosis.","authors":"Carrie Richardson, Mehrbod S Javadi, Ami A Shah, Caoilfhionn Connolly, Lilja B Solnes, Fredrick M Wigley, Laura K Hummers, Lisa Christopher-Stine","doi":"10.3389/fnume.2025.1593825","DOIUrl":"10.3389/fnume.2025.1593825","url":null,"abstract":"<p><strong>Background: </strong>Calcinosis is a morbid complication of dermatomyositis (DM) and systemic sclerosis (SSc) with no effective pharmacologic treatment or validated whole-body assessment modality. ¹⁸F-NaF PET/CT may help to quantify and characterize calcinosis.</p><p><strong>Methods: </strong>In this pilot study, we enrolled three adults with DM and three with SSc, all with new calcinosis deposits. Each underwent ¹⁸F-NaF PET/CT and clinical examination with semi-quantitative scoring of calcinosis. We described the ¹⁸F-NaF PET/CT findings and compared these to CT imaging alone as well as to clinical examination.</p><p><strong>Results: </strong>Calcinosis was noted on ¹⁸F-NaF PET/CT in the subcutaneous tissue in all patients and the muscle in three patients, including two with SSc. The average semi-quantitative score was 23.5 by ¹⁸F-NaF PET/CT and 20 by clinical exam. Wilcoxon signed rank test indicated greater scores by ¹⁸F-NaF PET/CT than by clinical exam (<i>p</i> = 0.0264). ¹⁸F-NaF uptake varied among calcinosis deposits and occurred without corresponding calcifications on CT.</p><p><strong>Conclusions: </strong>¹⁸F-NaF PET/CT appears to be a sensitive method of detecting and characterizing calcinosis that provides both quantitative and qualitative data beyond what can be obtained by physical examination or CT alone. ¹⁸F-NaF uptake occurs in muscle in both SSc and DM, suggesting the possibility that myositis may be driving calcinosis in a subset of patients with SSc.</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":"5 ","pages":"1593825"},"PeriodicalIF":0.0,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12162990/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144303826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum: Can ChatGPT help patients understand radiopharmaceutical extravasations?","authors":"Madeleine Alvarez","doi":"10.3389/fnume.2025.1534645","DOIUrl":"https://doi.org/10.3389/fnume.2025.1534645","url":null,"abstract":"<p><p>[This corrects the article DOI: 10.3389/fnume.2024.1469487.].</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":"5 ","pages":"1534645"},"PeriodicalIF":0.0,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12159049/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144287353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of FAPI PET/CT in patients with lymphoma: a systematic review.","authors":"Natale Quartuccio, Stefania Nicolosi, Sabina Pulizzi, Dante D'Oppido, Salvatore Ialuna","doi":"10.3389/fnume.2025.1589903","DOIUrl":"10.3389/fnume.2025.1589903","url":null,"abstract":"<p><strong>Introduction: </strong>Fluorodeoxyglucose (FDG) PET/CT is typically the reference imaging method for assessing and tracking lymphomas. However, fibroblast activation protein inhibitor (FAPI) PET is being explored as a potentially useful option, especially when Fluorodeoxyglucose (FDG) scans do not show clear results.</p><p><strong>Methods: </strong>For this systematic review, two researchers searched PubMed/MEDLINE and Cochrane CENTRAL for studies on FAPI PET/CT in lymphoma patients.</p><p><strong>Results: </strong>The literature search initially retrieved 249 articles. After removing duplicates and screening titles and abstracts, and full text, there was a final selection of 15 articles (3 original studies and 12 case reports), encompassing a total of 270 patients. The three original studies were judged to have a low risk of bias according to the QUADAS-2 criteria. The systematic review reveals that FAPI PET/CT exhibits lower diagnostic sensitivity than [¹⁸F]FDG PET/CT in lymphomas characterized by low FAP expression. Nevertheless, FAPI PET/CT retains potential as a complementary imaging modality.</p><p><strong>Discussion: </strong>[¹⁸F]FDG PET/CT remains the gold standard in lymphoma imaging, but FAPI PET/CT can potentially provide supplementary information regarding the molecular characteristics of lymphomas. FAPI PET/CT may have prognostic and therapeutic implications. In particular, it could help identify lymphoma subgroups with distinct stromal environments, potentially serving as a prognostic biomarker. Further large-scale prospective studies are warranted to validate its role in lymphoma management.</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":"5 ","pages":"1589903"},"PeriodicalIF":0.0,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12101064/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144144711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of carbonic anhydrase-IX-targeted trifunctional radioligands between linear- and branched-chain arrangements.","authors":"Kazuma Nakashima, Takayoshi Ichinose, Hiroyuki Watanabe, Masahiro Ono","doi":"10.3389/fnume.2025.1585027","DOIUrl":"https://doi.org/10.3389/fnume.2025.1585027","url":null,"abstract":"<p><strong>Background: </strong>Carbonic anhydrase-IX (CA-IX) is overexpressed in tumors due to hypoxic conditions and considered an attractive biomarker for tumor-targeting radioligands. The introduction of an albumin binder (ALB) to radioligands can delay their renal clearance, resulting in increased radioactivity delivered to tumors and decreased renal uptake of radioligands. In this study, we designed novel CA-IX-targeted trifunctional radioligands consisting of imidazothiadiazole sulfonamide (IS) as a CA-IX-targeted ligand, DOTA as a chelator with four free carboxylic groups, and lysine-conjugated 4-(<i>p</i>-iodophenyl)butyric acid (Lys-IPBA) as ALB, with IS-[¹¹¹In]In-DOTADG-ALB in a linear-chain arrangement and [¹¹¹In]In-DOTAGA-ALB-IS in a branched-chain arrangement. Fundamental properties of IS-[¹¹¹In]In-DOTADG-ALB and [¹¹¹In]In-DOTAGA-ALB-IS were evaluated by <i>in vitro</i> and <i>in vivo</i> assays.</p><p><strong>Methods: </strong>IS-DOTADG-ALB and DOTAGA-ALB-IS were synthesized and radiolabeled with [¹¹¹In]InCl₃. The stability of IS-[¹¹¹In]In-DOTADG-ALB and [¹¹¹In]In-DOTAGA-ALB-IS was evaluated by HPLC analysis after incubation in murine plasma. A cell saturation binding assay using CA-IX-positive HT-29 cells and albumin-binding assay were performed for IS-[¹¹¹In]In-DOTADG-ALB and [¹¹¹In]In-DOTAGA-ALB-IS to evaluate their capacity to bind CA-IX and albumin. Biodistribution assays of IS-[¹¹¹In]In-DOTADG-ALB and [¹¹¹In]In-DOTAGA-ALB-IS were performed using HT-29 tumor-bearing mice to evaluate their pharmacokinetics.</p><p><strong>Results: </strong>IS-[¹¹¹In]In-DOTADG-ALB and [¹¹¹In]In-DOTAGA-ALB-IS were successfully synthesized by ligand substitution reaction from their corresponding precursors. IS-[¹¹¹In]In-DOTADG-ALB and [¹¹¹In]In-DOTAGA-ALB-IS exhibited similar stabilities in murine plasma and affinities to CA-IX, although the affinities to albumin were higher for [¹¹¹In]In-DOTAGA-ALB-IS compared with IS-[¹¹¹In]In-DOTADG-ALB. In the biodistribution assays, [¹¹¹In]In-DOTAGA-ALB-IS showed higher blood retention and tumor accumulation and lower renal uptake than IS-[¹¹¹In]In-DOTADG-ALB, reflecting their albumin-binding affinities.</p><p><strong>Conclusion: </strong>These data suggest that the branched-chain arrangement of DOTAGA-ALB-IS may be useful for the design of CA-IX-targeted radioligands consisting of an IS ligand, DOTA, and Lys-IPBA.</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":"5 ","pages":"1585027"},"PeriodicalIF":0.0,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12040898/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144059851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of bone-SPECT/CT and Na[¹⁸F]F-PET/CT in hyperparathyroidism.","authors":"Wouter van der Bruggen, Bernard F Bulten","doi":"10.3389/fnume.2025.1565906","DOIUrl":"https://doi.org/10.3389/fnume.2025.1565906","url":null,"abstract":"<p><p>Hyperparathyroidism disrupts the balance of physiological bone formation and resorption by upregulating osteoclast activity. This leads to hypercalcemia, resulting in osteoporosis and eventually the formation of \"brown tumors.\" Currently used radiological and nuclear medicine imaging for primary hyperparathyroidism face challenges in accurately diagnosing bone-related complications. Molecular bone imaging techniques routinely consist of bone scintigraphy, with possible addition of bone-SPECT/CT. Recently, renewed interest has emerged in the use of Na[¹⁸F]F-PET/CT. Both applications are highly sensitive to <i>in vivo</i> osteoblast activity. However, the latter technique offers improved spatial resolution and sensitivity, as well as shorter incubation and faster scanning. This article summarizes current limitations and potential improvements in bone-SPECT/CT and Na[¹⁸F]F-PET/CT imaging in selected patients with hyperparathyroidism, compared to other relevant techniques and clinical parameters.</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":"5 ","pages":"1565906"},"PeriodicalIF":0.0,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12041007/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144051735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Case Report: The role of bone scans in detecting Ribbing disease.","authors":"Abel Dambrain, Clément Bouron, Franck Lacoeuille","doi":"10.3389/fnume.2025.1527159","DOIUrl":"10.3389/fnume.2025.1527159","url":null,"abstract":"<p><p>In this case, we report the usefulness of bone scintigraphy in evaluating osteoarticular pain when the diagnosis is unclear after standard morphological imaging. A 24-year-old male patient exhibited mild left tibial pain that had been intensifying over a period of 2 years. The initial radiological evaluation suggested a diagnosis of pediatric tibial bone marrow osteosclerosis associated with periostitis, based on standard radiographs and MRI. However, a complementary bone scan was required for confirmation and showed moderate hyperemia and severe hyperfixation of the tibial lesion along with similar lesions on the left femur, both humeri, and the right ulna. These new findings led to a diagnosis of Ribbing disease, a rare sclerosing bone dysplasia.</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":"5 ","pages":"1527159"},"PeriodicalIF":0.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11936802/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143722909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"18F-FDG-PET/CT for polymyalgia rheumatica: agreement and diagnostic accuracy of routine PET scan report vs. standardized PMR PET scores.","authors":"Kornelis S M van der Geest, Rob G J Grootelaar, Karin Bouwman, Maria Sandovici, Andor W J M Glaudemans, Elisabeth Brouwer, Riemer H J A Slart","doi":"10.3389/fnume.2025.1550881","DOIUrl":"10.3389/fnume.2025.1550881","url":null,"abstract":"<p><strong>Background: </strong>¹⁸F-FDG-PET/CT may reveal widespread inflammation of musculoskeletal structures in polymyalgia rheumatica (PMR). Currently, scans are subjectively analysed based on the overall gestalt of the scan. Standardized PET scores may potentially aid the interpretation of the scans for suspected PMR. Here, we compared the agreement and diagnostic accuracy of routine PET scan reports vs. the most validated PET scores for PMR.</p><p><strong>Methods: </strong>68 consecutive patients with suspected PMR (treatment-naïve, <i>n</i> = 29; already treated, <i>n</i> = 39) undergoing ¹⁸F-FDG-PET/CT were included. In glucocorticoid-treated patients, complete tapering was pursued prior to the scan. Conclusions of routine PET scan reports were interpretated by three independent readers as \"PMR\", \"not PMR\" or \"unclear\". The Leuven and Leuven/Groningen scores were determined. Agreement of scan report interpretation, and agreement of routine scan reports and PET scores were determined. Sensitivity and specificity were determined for the routine scan report and the two scores, with the clinical diagnosis established after 6 months follow-up as the reference standard.</p><p><strong>Results: </strong>A diagnosis of PMR was made in 45/68 patients. Routine scan reports were uniformly rated by all three readers in 54 (78%) cases. Following a consensus meeting, scans were rated as \"PMR\" in 43 cases, \"unclear\" in 10 cases and \"not PMR\" in 15 cases. The routine scan report showed a sensitivity of 82% and specificity of 74%, if \"unclear\" cases were considered negative for PMR. The Leuven and Leuven/Groningen Scores showed similar diagnostic accuracy. Agreement between the routine scan report and PET scores was good (Cohen's kappa 0.60-0.64), if \"unclear\" cases were excluded from the analysis. Among 8/10 \"unclear\" cases, the PMR PET Scores accurately distinguished between PMR/PMR-mimicking inflammatory conditions and non-inflammatory conditions. Agreement and diagnostic accuracy of routine scan reports and PET scores were better among treatment-naïve patients than those that had been treated previously.</p><p><strong>Conclusion: </strong>Our study reveals that routine PET scan reports for suspected PMR can be interpreted differently between readers. Although the routine PET scan reports and PMR PET scores did not always agree, they demonstrated similar diagnostic accuracy, with the highest accuracy observed in treatment-naive patients. The Leuven and Leuven/Groningen score could especially be helpful for cases in which the nuclear medicine physician is uncertain.</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":"5 ","pages":"1550881"},"PeriodicalIF":0.0,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11931067/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143702395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bayesian modeling with locally adaptive prior parameters in small animal imaging.","authors":"Muyang Zhang, Robert G Aykroyd, Charalampos Tsoumpas","doi":"10.3389/fnume.2025.1508816","DOIUrl":"10.3389/fnume.2025.1508816","url":null,"abstract":"<p><p>Medical images are hampered by noise and relatively low resolution, which create a bottleneck in obtaining accurate and precise measurements of living organisms. Noise suppression and resolution enhancement are two examples of inverse problems. The aim of this study is to develop novel and robust estimation approaches rooted in fundamental statistical concepts that could be utilized in solving several inverse problems in image processing and potentially in image reconstruction. In this study, we have implemented Bayesian methods that have been identified to be particularly useful when there is only limited data but a large number of unknowns. Specifically, we implemented a locally adaptive Markov chain Monte Carlo algorithm and analyzed its robustness by varying its parameters and exposing it to different experimental setups. As an application area, we selected radionuclide imaging using a prototype gamma camera. The results using simulated data compare estimates using the proposed method over the current non-locally adaptive approach in terms of edge recovery, uncertainty, and bias. The locally adaptive Markov chain Monte Carlo algorithm is more flexible, which allows better edge recovery while reducing estimation uncertainty and bias. This results in more robust and reliable outputs for medical imaging applications, leading to improved interpretation and quantification. We have shown that the use of locally adaptive smoothing improves estimation accuracy compared to the homogeneous Bayesian model.</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":"5 ","pages":"1508816"},"PeriodicalIF":0.0,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11913876/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143659977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}