EJNMMI Research最新文献

{"title":"Evaluation of myocardial fibrosis and wall motion abnormality with ⁶⁸Ga-FAPI PET/MR in coronary heart disease.","authors":"Rui Luo, Zhenyu Zhao, Chuan Zhang, Ru-Shuai Li, Yanrong Wang, Qingle Meng, Yudan Ni, Bolin Wang, Lanhua Li, Luan Feng, Rui Yang, Lin Xie, Xin Chen, Ming-Rong Zhang, Feng Wang","doi":"10.1186/s13550-025-01246-2","DOIUrl":"10.1186/s13550-025-01246-2","url":null,"abstract":"<p><strong>Background: </strong>To explore the characteristics of cardiac fibroblast activation protein inhibitor (FAPI) PET/MR in coronary heart disease (CHD) and its association with abnormal wall motion.</p><p><strong>Results: </strong>In this prospective study, participants with CHD after PCI (Percutaneous Coronary Intervention) underwent gallium 68 (⁶⁸ Ga)-labeled FAPI PET/MR imaging. FAP signal was quantified using standardized uptake values. Cardiac MRI yielded functional parameters and area of injury (MRI non-viable). Abnormal wall motion identified by myocardial strain analysis was evaluated using integrated analysis of late gadolinium enhancement (LGE) and FAP signal. The correlations between FAP signal and clinical parameters were explored. Forty-two participants were included and FAP signal was higher in left ventricle regional myocardium compared with remote normal areas (SUVmax, 5.0 ± 1.8 vs 1.2 ± 0.4; p < .001). In total, 432 segments (432/714, 60.50%) displayed impaired wall motion. In integrated analysis, the highest wall motion abnormality score was observed in the FAPI active/MRI non-viable group (11.0 ± 5.2). FAP signal was positively correlated with K time (SUVpeak: R = 0.48; p = .046; SUVmean: R = 0.57; p = .014) and negatively correlated with Angle (SUVpeak: R =  - 0.52; p = .026; SUVmean: R =  - 0.56; p = .026) in thromboelastography. Immunohistochemical analysis revealed FAP-positive fibroblasts in the infarct and border zone, and robust expression of α-smooth muscle actin and vimentin.</p><p><strong>Conclusions: </strong>Simultaneous ⁶⁸ Ga- FAPI PET/MR offers novel insights into the regional pattern of fibroblast activation in CHD, and the fibroblast activation protein signal is associated with abnormal wall motion. Trial registration ClinicalTrials: ClinicalTrials.gov ID: NCT05867589. Registered 01 May 2023, https://clinicaltrials.gov/study/NCT05867589.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"89"},"PeriodicalIF":3.1,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12279661/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144674179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[^195mPt]Cisplatin for lung cancer imaging: a pilot study.","authors":"Denise S Hoogenkamp, Berlinda J de Wit-van der Veen, Jeske Hendriksen, Karlijn van der Schilden, Josefine A M Nanne, José S A Belderbos, Maddalena M Rossi, Martien P J Mooijer, Uta Funke, N Harry Hendrikse, Wouter V Vogel, Else A Aalbersberg","doi":"10.1186/s13550-025-01281-z","DOIUrl":"10.1186/s13550-025-01281-z","url":null,"abstract":"<p><strong>Background: </strong>Radiolabeled [^195mPt]cisplatin has been developed as a tool to determine the biodistribution of cisplatin in vivo through SPECT imaging and possibly aid in patient-selection. This feasibility study aimed to evaluate the (radiation) safety, biodistribution, and image quality of [^195mPt]cisplatin SPECT/CT in patients with non-small cell lung cancer (NSCLC). [^195mPt]Cisplatin was produced under GMP standards. Six patients received 100 MBq [^195mPt]cisplatin in their second or third week of chemoradiation therapy. Planar and SPECT/CT imaging were acquired at 1.5, 48, 120 and 168 h post-administration. Segmentation on SPECT for biodistribution and dosimetry was achieved using TotalSegmentator in 3DSlicer, and organ specific time-activity curves were generated through a mono-exponential curve fit. Effective and absorbed doses were obtained with S-values from IDAC-Dose 2.1. Toxicity was assessed using CTCAE criteria.</p><p><strong>Results: </strong>Six NSCLC patients received 100.9 ± 3.3 MBq [^195mPt]cisplatin at a radioactivity concentration of 11.1 ± 4.9 MBq/mL. No adverse events above grade 2 were observed. [^195mPt]Cisplatin had a long retention time with an effective half-life of 74.8 h. Uptake was highest in the liver and kidneys, which also resulted in the highest absorbed dose at 48.6 ± 7.9 mGy and 38.4 ± 7.3 mGy, respectively. Tumor uptake was similar to blood, with a ratio of 1.0 ± 0.05.</p><p><strong>Conclusion: </strong>[^195mPt]Cisplatin is safe to use for imaging in patients with NSCLC when injecting 100 MBq, reaching a mean effective dose of 14.6 ± 1.5 mSv. The image quality of [^195mPt]cisplatin was suitable for SPECT imaging and quantification. Tumor uptake was similar to blood.</p><p><strong>Trial registration: </strong>CCMO, NL74272.031.21. Registered 28 January 2022, https://www.onderzoekmetmensen.nl/nl/trial/55147 .</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"87"},"PeriodicalIF":3.1,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12267755/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144642099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the effect of locoregional treatment on metabolic liver function in hepatocellular carcinoma using ¹⁸F-FDGal PET/CT.","authors":"Mona Kjærbøl Kristiansen, Kirstine Petrea Bak-Fredslund, Stine Kramer, Gerda Elisabeth Villadsen, Michael Sørensen","doi":"10.1186/s13550-025-01285-9","DOIUrl":"10.1186/s13550-025-01285-9","url":null,"abstract":"","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"88"},"PeriodicalIF":3.1,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12267743/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144648852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of androgen blockade on [⁶⁸Ga]Ga-PSMA-11 and [¹⁸F]FDG PET uptake in patients with recurrent or metastatic salivary duct carcinoma: a prospective imaging study.","authors":"Niels J van Ruitenbeek, Maike J M Uijen, Chantal M L Driessen, Maartje C van Rijk, Steffie M B Peters, Bastiaan M Privé, Gerald W Verhaegh, Adriana C H van Engen-van Grunsven, Martin Gotthardt, James Nagarajah, Carla M L van Herpen","doi":"10.1186/s13550-025-01275-x","DOIUrl":"10.1186/s13550-025-01275-x","url":null,"abstract":"<p><strong>Background: </strong>The expression of prostate-specific membrane antigen (PSMA), a target for oncological imaging and treatment, is upregulated by androgen blockade in prostate cancer. Salivary duct carcinoma (SDC), an aggressive histological subtype of salivary gland cancer, resembles prostate cancer in terms of PSMA and androgen receptor (AR) expression. A similar upregulation of PSMA in SDC would have implications for future studies with PSMA-targeted imaging and therapy. Additionally, FDG PET/CT scans are frequently used for SDC imaging, but the effect of androgen blockade on FDG uptake is unknown. This study investigated the effect of combined androgen blockade (CAB) on tumour PSMA and FDG uptake in patients with SDC.</p><p><strong>Results: </strong>Eight patients with recurrent and/or metastatic AR-positive SDC who started CAB (goserelin plus bicalutamide) as standard of care were prospectively enrolled. [⁶⁸ Ga]Ga-PSMA-11 and [¹⁸F]FDG PET/CT scans were performed within 21 days before and 21 ± 7 days after CAB initiation. PET parameters, including SUV_max, were obtained for PSMA and FDG positive lesions. A total of 80 metastatic lesions were analysed on a per-lesion basis. SUV_max changes after CAB initiation were categorised as increased (≥ + 20%), stable (between -20% and + 20%), or decreased (≤ -20%). The PSMA SUV_max increased in 20 lesions (25%), remained stable in 46 lesions (58%), and decreased in 14 lesions (18%), with no significant overall change (Wilcoxon signed rank test, p = 0.74). The FDG SUV_max increased in 35 lesions (44%), remained stable in 39 lesions (49%), and decreased in 6 lesions (8%), with a significant overall median increase of + 0.97 (Wilcoxon signed rank test, p < 0.001). The median PFS was 2.2 months (95% confidence interval 1.7-2.7 months).</p><p><strong>Conclusions: </strong>Androgen blockade in patients with recurrent and/or metastatic SDC did not induce a significant increase in tumour PSMA uptake after three weeks. In contrast, tumour FDG uptake increased significantly after three weeks of CAB, which may reflect the poor tumour response in this cohort and/or a transient treatment-related effect.</p><p><strong>Trial registration: </strong>ClinicalTrials.gov, NCT04214353. Registered 13 December 2019.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"86"},"PeriodicalIF":3.1,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12263521/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144636548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"<ArticleTitle xmlns:ns0=\"http://www.w3.org/1998/Math/MathML\">Machine learning to identify suitable boundaries for band-pass spectral analysis of dynamic [ <ns0:math><ns0:mmultiscripts><ns0:mrow /> <ns0:mrow /> <ns0:mn>11</ns0:mn></ns0:mmultiscripts> </ns0:math> C]Ro15-4513 PET scan and voxel-wise parametric map generation.","authors":"Zeyu Chang, Colm J McGinnity, Rainer Hinz, Manlin Wang, Joel Dunn, Ruoyang Liu, Mubaraq Yakubu, Paul Marsden, Alexander Hammers","doi":"10.1186/s13550-025-01251-5","DOIUrl":"10.1186/s13550-025-01251-5","url":null,"abstract":"<p><strong>Background: </strong>Spectral analysis is a model-free PET quantification technique that treats the time-space signal as an impulse response to a bolus injection. Band-pass spectral analysis, considering specific frequency ranges, enables calculation of separate parametric maps of receptor subtype tracer binding for suitable radiopharmaceuticals such as [ <math><mmultiscripts><mrow></mrow> <mrow></mrow> <mn>11</mn></mmultiscripts> </math> C]Ro15-4513 binding to GABA_A <math><mi>α</mi></math> 1/5 subunits. Frequency ranges are based on inspection of spectra, prior knowledge of receptor distribution, and blocking studies. The process currently requires the manual selection of frequency ranges based on the data. To enhance the efficiency of band-pass spectral analysis and extend its application to a broader range of tracers, we propose employing machine learning to automate the selection of spectral boundaries. Based on these boundaries, voxel-wise parametric maps can be generated. The machine learning models utilized in this study include 1D Convolutional Neural Network, Neural Network, Support Vector Machine, Logistic Regression, K-nearest neighbors, and Fine Tree.</p><p><strong>Results: </strong>The best machine learning model, Fine Tree, agreed with the manual frequency boundary in 96.92% of 3185 ROIs. The absolute mean error was 3.80% for slow component volume-of-distribution ( <math><msub><mtext>V</mtext> <mrow><mi>slow</mi></mrow> </msub> </math> , largely representing <math><mi>α</mi></math> 5) and 4.74% for fast component volume-of-distribution( <math><msub><mtext>V</mtext> <mrow><mi>fast</mi></mrow> </msub> </math> , largely representing <math><mi>α</mi></math> 5), while the relative error was 2.83% ± 43.47% for <math><msub><mtext>V</mtext> <mrow><mi>slow</mi></mrow> </msub> </math> and <math><mo>-</mo></math> 2.01% ± 78.04% for <math><msub><mtext>V</mtext> <mrow><mi>fast</mi></mrow> </msub> </math> . The median test-retest intraclass correlation coefficient across six representative regions was 0.770 for <math><msub><mtext>V</mtext> <mrow><mi>slow</mi></mrow> </msub> </math> , 0.670 for <math><msub><mtext>V</mtext> <mrow><mi>fast</mi></mrow> </msub> </math> , and 0.502 for total component volume-of-distribution( <math><msub><mtext>V</mtext> <mi>d</mi></msub> </math> ). Parametric maps applying different boundaries for different ROIs were generated.</p><p><strong>Conclusion: </strong>The machine learning model developed provided accurate boundary predictions in 96.92% of regions, with minimal average bias. However, when errors occur, they can be large, owing to the sparsity of peaks. The model enables setting boundaries automatically for the vast majority of regions, followed by manual checking of the outliers. It opens the possibility of accelerating analyses e.g. of GABA_A <math><mi>α</mi></math> 1/2/3/5 subunit binding using [¹¹C]flumazenil and of extending band-pass spectral analysis to other r","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"85"},"PeriodicalIF":3.1,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12254443/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144607767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Altered glucose metabolism in default mode network and prefrontal circuit in patients with Kallmann syndrome.","authors":"Chunqing Zhou, Xueying Wang, Meichao Men, Xiaoping Yi, Ke Cao, Weidan Pu, Marcus Hacker, Xiang Li, Min Zhao","doi":"10.1186/s13550-025-01282-y","DOIUrl":"10.1186/s13550-025-01282-y","url":null,"abstract":"<p><strong>Background: </strong>This study delineates brain metabolic signatures underlying neuroendocrine-psychosocial interactions in Kallmann syndrome (KS), a rare genetic disorder characterized by congenital hypogonadism and anosmia. In this prospective case-control study, 30 KS patients and 30 matched healthy controls (HCs) underwent brain [¹⁸F]FDG PET scans, sex hormone assays, and standardized neuropsychological assessments. A voxel-wise group comparison analysis was conducted to identify clusters of brain metabolic patterns between KS patients and HCs. Subsequently, correlation and mediation analyses were performed to investigate the interrelationships and mediating effect among brain metabolic patterns, sex hormone levels, and psychosocial factors.</p><p><strong>Results: </strong>We identified six hypermetabolic clusters in KS patients, predominantly located in the fronto-limbic system and the default mode network (DMN) in KS patients. These clusters of hypermetabolism were significantly associated fertility anxiety scale (FAS), health information avoidance scale (HIAS) and health information overload scale (HIOS). In addition, mediation analysis indicated that bilateral basal ganglia hypermetabolism acted as a significant mediator between HIAS and FAS (β = 0.274, P = 0.031).</p><p><strong>Conclusion: </strong>Patients with KS exhibited a distinct hypermetabolism pattern in the DMN-prefrontal circuit, which functionally bridges neuroendocrine dysfunction and reproductive health anxiety.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"84"},"PeriodicalIF":3.1,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12254444/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144607768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiation dosimetry and fasting-dependent hepatobiliary clearance of the VAChT-specific PET radioligand ¹⁸F-VAT in humans.","authors":"Scott A Norris, Noah L Goldman, Mahdjoub Hamdi, Stephen M Moerlein, Richard Laforest, Morvarid Karimi, Joel S Perlmutter, Zhude Tu","doi":"10.1186/s13550-025-01273-z","DOIUrl":"10.1186/s13550-025-01273-z","url":null,"abstract":"<p><strong>Background: </strong>The vesicular acetylcholine transporter ligand (-)-(1-((2R,3R)-8-(2-[(18)F]fluoro-ethoxy)-3-hydroxy-1,2,3,4-tetrahydronaphthalen-2-yl)piperidin-4-yl)(4-fluorophenyl)-methanone (¹⁸F -VAT) enables positron emission tomography PET quantification of cholinergic dysfunction in neurologic and psychiatric disorders. Determining its bio-distribution and dose exposure in humans is essential for clinical implementation, particularly given hepatobiliary clearance observed in pre-clinical models. Based on pre-clinical data, eight healthy subjects (4 males, 4 females) received 385-533 MBq ¹⁸F-VAT immediately followed by three sequential whole-body PET/CT scans. PET data were collected under three different fasting conditions relative to administration of Ensure®Plus oral supplement and PET image acquisition: (1) complete fasting (n = 3), (2) oral partial fasting (n = 3), or (3) non-fasting (n = 2). We defined volumes of interest (VOIs), and generated organ time-activity curves (TACs). Organ radiation dosimetry was calculated using OLINDA/EXM v2.2 software.</p><p><strong>Results: </strong>There were no adverse events after ¹⁸F-VAT dosing. Radioactivity accumulated predominantly in the brain, hepatobiliary system, small intestine, bone, and urinary bladder. Across all fasting states, organ dosimetry revealed gallbladder as the critical organ (201.0 μSv/MBq) followed by liver (64.3 μSv/MBq), with a gender averaged effective dose of 17.5 ± 2.1 μSv/MBq (15.7 and 19.4 μSv/MBq for males and females, respectively.) Mean gallbladder time integrated activity significantly differed across non-fasting (36.6 MBq*h, 155.5 µSv/MBq), partial fasting (21.8 MBq*h, 107.6 µSv/MBq) and fasting PET acquisition (74.1 MBq*h, 270.5 µSv/MBq) (Kruskal-Wallis H 6.5, p = 0.04).</p><p><strong>Conclusions: </strong>Human bio-distribution data showed high retention of ¹⁸F-VAT in the gallbladder and liver, where rat dosimetry studies do not accurately predict a safety profile given lack of gallbladder. Human dosimetry data appear different from fasting non-human primate data, indicating that up to 249 MBq (6.7 mCi) of ¹⁸F-VAT can be administered without exceeding a maximum dose to the gallbladder of 50 mSv (5 rem) without consideration of fasting state. Oral supplementation, administered just before and especially 90 min after ¹⁸F-VAT administration, accelerates gallbladder clearance. This reduces critical organ radiation exposure, allowing an administered dose of ¹⁸F-VAT to 465 MBq (12.6 mCi) in the optimal partial fasting state without exceeding a gallbladder dose of 50 mSv (5 rem).</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"83"},"PeriodicalIF":3.1,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12234429/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144575077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tolerability of PSMA radioligand therapy in metastatic prostate cancer patients with baseline mild to moderate leukopenia.","authors":"Moritz B Bastian, Tilman Speicher, Arne Blickle, Caroline Burgard, Julius L D Bastian, Mark Bartholomä, Andrea Schaefer-Schuler, Stephan Maus, Samer Ezziddin, Florian Rosar","doi":"10.1186/s13550-025-01280-0","DOIUrl":"10.1186/s13550-025-01280-0","url":null,"abstract":"<p><strong>Background: </strong>Aim of this study was to analyze the safety of prostate-specific membrane antigen radioligand therapy (PSMA-RLT) in patients with metastatic castration-resistant prostate cancer (mCRPC) with preexisting mild to moderate leukopenia (CTCAE ≥ 1).</p><p><strong>Results: </strong>Thirty-seven mCRPC patients with preexisting leukopenia (leukocyte count < 3.8 × 10⁹/L) were included in this study. Patients received a median of 3 cycles of [¹⁷⁷Lu]Lu-PSMA-617 (range 1-9). No significant difference in leukocyte counts was observed between baseline and follow-up after each PSMA-RLT cycle: first cycle (3.0 ± 0.5 at baseline vs. 3.4 ± 1.4 at follow up [in × 10⁹/L], p = 0.0921), second cycle (3.1 ± 0.4 vs. 3.8 ± 1.7, p = 0. 0.0509), and third cycle (3.1 ± 0.4 vs. 3.2 ± 2.0, p = 0.2929), respectively. Similarly, baseline and end of treatment values, irrespective of the number of administered cycles, did not reveal a significant difference (3.0 ± 0.5 vs. 3.5 ± 1.4, p = 0.0684). After the end of therapy, irrespective of the number of administered cycles, 27% patients remained stable in terms of CTCAE scoring, 46% changed to a higher score and 27% improved to a lower score.</p><p><strong>Conclusion: </strong>Although marked preexisting leukopenia is often considered a relative contraindication for PSMA-RLT, our findings indicate that PSMA-RLT is feasible in patients with leukopenia of CTCAE grade ≥ 1. In our cohort, leukocyte counts remained stable without significant RLT-induced deterioration. Therefore, patients with leukopenia should not be categorically excluded from receiving PSMA-RLT.</p><p><strong>Trial registration: </strong>Clinicaltrials.gov identifier: NCT04833517, registered 01.01.2016.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"82"},"PeriodicalIF":3.1,"publicationDate":"2025-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12229971/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144575078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Model selection for dynamic PET compartmental modelling of ¹⁸F-FDG uptake using a long axial field-of-view PET scanner with delay and motion correction.","authors":"Hamed Moradi, Rajat Vashistha, Kieran O'Brien, Amanda Hammond, Axel Rominger, Hasan Sari, Kuangyu Shi, Viktor Vegh, David Reutens","doi":"10.1186/s13550-025-01277-9","DOIUrl":"10.1186/s13550-025-01277-9","url":null,"abstract":"<p><strong>Background: </strong>In dynamic PET with tracer kinetic modeling, model complexity is an important but often under-recognised challenge affecting robust parameter estimation, particularly for noisy data. Traditional methods often neglect tissue heterogeneity and apply a single model universally. We applied a model selection approach alongside delay and motion correction, enabling the selection of models with varying complexity to better account for tissue heterogeneity.</p><p><strong>Results: </strong>The study included five subjects with breast cancer undergoing dynamic ¹⁸F-FDG PET imaging using a long axial field of view scanner. Voxel-wise kinetic model parameter estimation utilized five compartmental models, with the best model chosen using the Akaike Information Criterion. The model selection revealed diverse kinetic models within breast cancer lesions voxel-wise, with reduced parameter estimation variability attributed to the choice of simpler models. Applying delay and motion correction reduced the mean coefficient of variation in estimated kinetic parameters by 25%.</p><p><strong>Conclusions: </strong>We applied a standard model selection approach to identify the optimal compartmental model for voxel-wise parameter estimation in long field-of-view dynamic PET imaging. Our results demonstrate that accounting for tissue heterogeneity in breast lesions is critical for accurate quantification. Additionally, delay and motion correction were shown to improve image quality, enhance quantification accuracy, and support more reliable model selection.</p><p><strong>Clinical trial registration: </strong>Clinical trial number: not applicable.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"81"},"PeriodicalIF":3.1,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12227408/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144559524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"¹⁸F-FDG dose reduction using deep learning-based PET reconstruction.","authors":"Ryuji Akita, Komei Takauchi, Mana Ishibashi, Shota Kondo, Shogo Ono, Kazushi Yokomachi, Yusuke Ochi, Masao Kiguchi, Hidenori Mitani, Yuko Nakamura, Kazuo Awai","doi":"10.1186/s13550-025-01269-9","DOIUrl":"10.1186/s13550-025-01269-9","url":null,"abstract":"<p><strong>Background: </strong>A deep learning-based image reconstruction (DLR) algorithm that can reduce the statistical noise has been developed for PET/CT imaging. It may reduce the administered dose of ¹⁸F-FDG and minimize radiation exposure while maintaining diagnostic quality. This retrospective study evaluated whether the injected ¹⁸F-FDG dose could be reduced by applying DLR to PET images. To this aim, we compared the quantitative image quality metrics and the false-positive rate between DLR with a reduced ¹⁸F-FDG dose and Ordered Subsets Expectation Maximization (OSEM) with a standard dose.</p><p><strong>Results: </strong>This study included 90 oncology patients who underwent ¹⁸F-FDG PET/CT. They were divided into 3 groups (30 patients each): group A (¹⁸F-FDG dose per body weight [BW]: 2.00-2.99 MBq/kg; PET image reconstruction: DLR), group B (3.00-3.99 MBq/kg; DLR), and group C (standard dose group; 4.00-4.99 MBq/kg; OSEM). The evaluation was performed using the signal-to-noise ratio (SNR), target-to-background ratio (TBR), and false-positive rate. DLR yielded significantly higher SNRs in groups A and B than group C (p < 0.001). There was no significant difference in the TBR between groups A and C, and between groups B and C (p = 0.983 and 0.605, respectively). In group B, more than 80% of patients weighing less than 75 kg had at most one false positive result. In contrast, in group B patients weighing 75 kg or more, as well as in group A, less than 80% of patients had at most one false-positives.</p><p><strong>Conclusions: </strong>Our findings suggest that the injected ¹⁸F-FDG dose can be reduced to 3.0 MBq/kg in patients weighing less than 75 kg by applying DLR. Compared to the recommended dose in the European Association of Nuclear Medicine (EANM) guidelines for 90 s per bed position (4.7 MBq/kg), this represents a dose reduction of 36%. Further optimization of DLR algorithms is required to maintain comparable diagnostic accuracy in patients weighing 75 kg or more.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"78"},"PeriodicalIF":3.1,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12214151/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144539588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}