Annals of Nuclear Medicine最新文献

{"title":"Assessing osteoporosis and bone mineral density through ¹⁸F-NaF uptake at lumbar spine.","authors":"Jinquan Huang, Jingze Li, Zuguo Li, Jie Qin, Xingyu Mu, Wei Fu","doi":"10.1007/s12149-024-01982-w","DOIUrl":"https://doi.org/10.1007/s12149-024-01982-w","url":null,"abstract":"<p><strong>Objectives: </strong>The use of ¹⁸F-Sodium fluoride (NaF) PET/CT is established in the detection of metastatic bone disease, yet its utility in osteoporosis remains underexplored. This research aims to assess the variations in ¹⁸F-NaF uptake among individuals with differing bone mineral density (BMD) and to examine the relationship between ¹⁸F-NaF uptake and BMD.</p><p><strong>Methods: </strong>In this retrospective study, 199 patients (average age 56 ± 6, comprising 52 males and 147 females) with a history of cancer were analyzed. Each participant underwent both ¹⁸F-NaF PET/CT and lumbar dual-energy X-ray absorptiometry (DXA) scans within a span of 7 days. Based on DXA outcomes, patients and their lumbar vertebrae were categorized into normal BMD, osteopenia, and osteoporosis groups. The lumbar ¹⁸F-NaF uptake across these groups were compared, and to explore the association between lumbar standardized uptake values (SUV) values and BMD. The efficacy of ¹⁸F-NaF uptake in diagnosing osteoporosis or osteopenia was also evaluated. Analysis was conducted using Mann-Whitney U tests, Spearman regression, and receiver operating characteristic (ROC) curve analysis through GraphPad Prism 10.0.</p><p><strong>Results: </strong>A total of 796 lumbar vertebrae from 199 patients were measured. It was observed that osteoporotic patients had significantly lower ¹⁸F-NaF uptake than those with osteopenia and normal BMD across the L1-L4 lumbar vertebrae (P < 0.0001). In a vertebra-based analysis, normal BMD vertebrae exhibited the highest maximum SUV(SUV_max) compared to osteopenic (8.13 ± 1.28 vs. 6.61 ± 1.01, P < 0.0001) and osteoporotic vertebrae (8.13 ± 1.28 vs. 4.82 ± 1.01, P < 0.0001). There was a positive correlation between lumbar ¹⁸F-NaF uptake and BMD across all vertebrae, with correlation coefficients exceeding 0.5 (range: 0.57-0.8). The area under the ROC curve values were notably high, at 0.96 for osteoporosis and 0.83 for osteopenia diagnosis.</p><p><strong>Conclusion: </strong>This study demonstrates distinct ¹⁸F-NaF uptake patterns among individuals with varying BMD levels, with a positive correlation between ¹⁸F-NaF uptake and BMD. These findings highlight the potential of ¹⁸F-NaF PET/CT as a supportive diagnostic method in the management of osteoporosis.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142339712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is second ¹³¹I treatment necessary for differentiated thyroid cancer patients and who could not benefit from it? A real-world retrospective study in China.","authors":"Canran Xiao, Ruoxin Xu, Yao Luo, Zeqing Xu, Caihua Tang","doi":"10.1007/s12149-024-01984-8","DOIUrl":"https://doi.org/10.1007/s12149-024-01984-8","url":null,"abstract":"<p><strong>Background: </strong>The efficacy of a second radioactive iodine-131 (¹³¹I) treatment in patients with differentiated thyroid cancer (DTC) who did not achieve an excellent response (ER) following initial ¹³¹I therapy remains controversy and the population that would derive limited benefit from it is currently unclear.</p><p><strong>Objectives: </strong>The aim of this retrospective study was to assess the efficacy of the second ¹³¹I treatment in DTC patients with non-ER after the initial ¹³¹I therapy, and to identify potential risk factors associated with non-benefit of the second ¹³¹I treatment.</p><p><strong>Methods: </strong>127 DTC patients who underwent two ¹³¹I treatments following thyroidectomy were included in this study, and the therapeutic response was evaluated after each ¹³¹I treatment. Beneficial treatment was defined as an improvement in therapy response grade (e.g. from indeterminate response to ER) after the second ¹³¹I treatment, while unbeneficial treatment was defined as no change or a downgrade in therapy response grade. The potential risk factors associated with the non-benefit of the second ¹³¹I treatment were identified using univariate and multivariate logistic regression models.</p><p><strong>Results: </strong>Following the second ¹³¹I treatment, therapy responses of 55.12% (70/127) of patients were reclassified to a better grade indicating treatment benefit, while 44.88% (57/127) showed no change or were reclassified to a worse grade suggesting no benefit from treatment. The non-benefit of the second ¹³¹I treatment was significantly associated with potential risk factors including stimulated thyroglobulin (sTg) level ≥ 11.46 ng/mL before the second ¹³¹I treatment, primary tumor size > 2 cm, status T2 or higher, N1b status and ATA high risk.</p><p><strong>Conclusions: </strong>The study results demonstrated that more than half of DTC patients could potentially benefit from a second ¹³¹I therapy. However, over 40% of patients exhibited no benefit in response to the second ¹³¹I treatment, suggesting potential overtreatment for this subgroup. Therefore, clinicians should exercise meticulous and precise decision-making based on identified risk factors when considering the necessity of a second ¹³¹I treatment.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142306999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection rate of gastrin-releasing peptide receptor (GRPr) targeted tracers for positron emission tomography (PET) imaging in primary prostate cancer: a systematic review and meta-analysis","authors":"Gokce Belge Bilgin,&nbsp;Cem Bilgin,&nbsp;Atakan Orscelik,&nbsp;Brian J. Burkett,&nbsp;Matthew P. Thorpe,&nbsp;Derek R. Johnson,&nbsp;Geoffrey B. Johnson,&nbsp;David F. Kallmes,&nbsp;Oliver Sartor,&nbsp;Ayse Tuba Kendi","doi":"10.1007/s12149-024-01978-6","DOIUrl":"10.1007/s12149-024-01978-6","url":null,"abstract":"<div><p>The gastrin-releasing peptide receptor (GRPr) has gained recognition as a promising target for both diagnostic and therapeutic applications in a variety of human cancers. This study aims to explore the primary tumor detection capabilities of [⁶⁸Ga] Ga-GRPr PET imaging, specifically in newly diagnosed intra-prostatic prostate cancer lesions (PCa). Following PRISMA-DTA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses of Diagnostic Test Accuracy Studies) guidelines, a systematic literature search was conducted using the Medline, Embase, Scopus, and Web of Science databases. Data regarding patient characteristics and imaging procedure details—including the type of radiotracer used, administered activity, image acquisition time, scanner modality, criteria, and detection rate of index test—were extracted from the included studies. The pooled patient-and lesion-based detection rates, along with their corresponding 95% confidence intervals (CI), were calculated using a random effects model. The final analysis included 9 studies involving 291 patients and 350 intra-prostatic lesions with [⁶⁸Ga] Ga-GRPr PET imaging in primary PCa. In per-patient-based analysis of [⁶⁸Ga] Ga-GRPr PET imaging, the pooled detection rates of overall and patients with Gleason score ≥ 7 were 87.09% (95% CI 74.98–93.82) and 89.01% (95% CI 68.17–96.84), respectively. In per-lesion-based analysis, the pooled detection rate [⁶⁸Ga] Ga-GRPr PET imaging was 78.54% (95% CI 69.8–85.29). The pooled detection rate mpMRI (multiparametric magnetic resonance imaging) in patient-based analysis was 91.85% (95% CI 80.12–96.92). The difference between the detection rates of the mpMRI and [⁶⁸Ga] Ga-GRPr PET imaging was not statistically significant (OR 0.90, 95% CI 0.23–3.51). Our findings suggest that [⁶⁸Ga] Ga-GRPr PET imaging has the potential as a diagnostic target for primary PCa. Future research is needed to determine the effectiveness of [⁶⁸Ga] Ga-GRPr PET in delivering additional imaging data and guiding therapeutic decisions.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"38 11","pages":"865 - 876"},"PeriodicalIF":2.5,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Next day sentinel node biopsy for melanoma after lymphoscintigraphy using 99mTc-labelled nanocolloid does not adversely affect long-term outcomes","authors":"Amit Roshan, Terouz Pasha, Georgios Kounidas, Suzanne Murphy, Luigi Aloj, John Buscombe, Animesh Patel, Amer Durrani","doi":"10.1007/s12149-024-01980-y","DOIUrl":"https://doi.org/10.1007/s12149-024-01980-y","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Objective</h3><p>Sentinel Lymph Node Biopsy (SLNB) is an important management tool for early-stage melanoma. Different radiopharmaceuticals are used internationally to localise the sentinel node using lymphoscintigraphy (LSG) before surgery. Recent reports have suggested that a delayed interval between LSG and SLNB using ^99mTc-labelled nanocolloid tracer has an adverse survival impact, but not with ^99mTc-labelled antimony sulphide colloid. This study aims to analyse survival outcome in a prospective cohort of melanoma patients undergoing same day or next day SLNB after LSG using ^99mTc-labelled nanocolloid.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>Outcome data were reviewed for patients undergoing SLNB, stratified by time interval between LSG and SLNB at a single UK academic centre. Kaplan–Meier survival analysis was used to assess overall survival (OS), melanoma-specific survival (MSS) and progression-free survival (PFS). Cox multivariable regression analysis identified independent risk factors.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>925 patients had LSG using the ^99mTc-nanocolloid tracer between 2009 and 2019, with a median follow-up of 6.36 years. No difference was seen on univariate analysis in OS, MSS, PFS, or nodal recurrence between patients undergoing same day or next day SLNB (Log-rank <i>P</i> = 0.437, 0.293, 0.587, 0.342 respectively). In addition, nodal recurrence as first site or anytime site of recurrence in SLNB negative patients was similar between the groups (Log-rank <i>P</i> = 0.093 and 0.457 respectively). Stratified analysis of time did not demonstrate an outcome difference (MSS Log-rank <i>P</i> = 0.938). Cox multivariable regression did not show time interval to independently influence OS, MSS or PFS.</p><h3 data-test=\"abstract-sub-heading\">Conclusions</h3><p>We do not find a significant effect on long-term outcomes when SLNB is performed the day after LSG with ^99mTc-labelled nanocolloid tracer. We infer that tracer migration is not clinically significant within 24 h of injection based on long term clinical outcome data.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"16 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Blood-pool SUV analysis of 99mTc-galactosyl human serum albumin (99mTc-GSA) normalized by blood volume for prediction of short-term survival in severe liver failure: preliminary report","authors":"Naoya Yama, Hiroomi Tatsumi, Masayuki Akatsuka, Masamitsu Hatakenaka","doi":"10.1007/s12149-024-01975-9","DOIUrl":"https://doi.org/10.1007/s12149-024-01975-9","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>This study evaluated the usefulness of SUV analysis of 99mTc-galactosyl human serum albumin (99mTc-GSA) scintigraphy including SUV analysis of the cardiac blood pool normalized by blood volume as a predictor of short-term survival in severe liver failure.</p><h3 data-test=\"abstract-sub-heading\">Patients and methods</h3><p>We enrolled 24 patients with severe liver failure who underwent 99mTc-GSA scintigraphy and were admitted to the intensive care unit. Patients were divided into survival and non-survival groups at 7, 14, and 28 days from the performance of 99mTc-GSA scintigraphy. From SPECT images we calculated SUVs of the cardiac blood pool, performing normalization for body weight, lean body weight, Japanese lean body weight, and blood volume and we calculated SUVs of the liver, normalizing by body weight, lean body weight, and Japanese lean body weight. We also calculated the uptake ratio of the heart at 15 min to that at 3 min (HH15) and the uptake ratio of the liver at 15 min to the liver plus the heart at 15 min (LHL15) from planar images of 99mTc-GSA scintigraphy.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>There were significant differences between the 7 day survival and non-survival groups for all SUVs of the heart and the liver and HH15, for 14 day survival groups in SUVs of the heart normalized by Japanese lean body weight and blood volume, and no significant differences between 28 day survival groups for any SUVs, HH15, or LHL15. Although the difference was not significant, SUV analysis of the heart normalized by blood volume showed the highest value for the area under the receiver-operating-characteristics curve for both 7 day and 14 day survival.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>SUV analysis of 99mTc-GSA including SUV analysis of cardiac blood pool normalized by blood volume is of value for prediction of short-term survival in cases with severe liver failure.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"1 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prognostic value of transient ischemic dilatation by 13N-ammonia PET MPI for short-term outcomes in patients with non-obstructive CAD","authors":"Yanni jia, Yingqi Hu, Lihong Yang, Xin Diao, Yuanyuan Li, Yanhui Wang, Ruonan Wang, Jianbo Cao, Sijin Li","doi":"10.1007/s12149-024-01976-8","DOIUrl":"https://doi.org/10.1007/s12149-024-01976-8","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Objective</h3><p>Transient ischaemic dilatation (TID) had incremental diagnostic and prognostic value in obstructive coronary artery disease (CAD), but its clinical significance in patients with non-obstructive CAD remains unknown. We aimed to explore the prognostic value of TID in patients with non-obstructive CAD by ¹³N-ammonia PET imaging.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>We retrospectively studied 131 consecutive patients with non-obstructive CAD undergoing one-day rest-stress ¹³N-ammonia PET myocardial perfusion imaging (MPI). TID was automatically generated using CardIQ Physio software. The receiver operative characteristic (ROC) curve was used to determine the optimal threshold of TID. The follow-up outcome was major adverse cardiac events (MACE), a composite of re-hospitalization for heart failure or unstable angina, late revascularization, non-fatal myocardial infarction, and cardiac death. Cardiac event-free survivals for normal and abnormal TID were compared using Kaplan–Meier plots and log-rank tests.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>During a median follow-up of 42.08 ± 17.67 months, 22 (16.7%) patients occurred MACE. The optimal cut-off value of TID was 1.03 based on MACE. Our preliminary outcome analysis suggests that TID-abnormal subjects had a lower overall survival probability. Furthermore, our multivariate analysis reveals abnormal TID was the only independent predictor for MACE in non-obstructive CAD. In the subgroup analysis, an abnormal TID was an independent predictor for MACE in patients with abnormal perfusion patterns.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>Among patients with non-obstructive CAD, PET-derived TID ≥ 1.03 may identify those with a high risk of subsequent MACE independently. It was also an independent risk factor for poor prognosis in patients with abnormal perfusion.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3><p> <i>CAD</i> coronary artery disease,<i> PET</i> positron emission tomography, <i>MPI</i> myocardial perfusion imaging, <i>TID</i> transient ischaemic dilatation,<i> MACE</i> major adverse cardiac events, <i>ROC</i> receiver operative characteristic.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"11 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation of advanced hybrid SPECT/CT system using dynamic anthropomorphic cardiac phantom","authors":"Elad Gelbart,&nbsp;Alexander Krakovich,&nbsp;Yigal Sherm,&nbsp;Gilad Rabin,&nbsp;Hagit Ratner,&nbsp;Mickey Scheinowitz,&nbsp;Ronen Goldkorn","doi":"10.1007/s12149-024-01966-w","DOIUrl":"10.1007/s12149-024-01966-w","url":null,"abstract":"<div><h3>Objective</h3><p>Myocardial blood flow (MBF) assessment can provide incremental diagnostic and prognostic information and thus the validation of dynamic SPECT is of high importance. We recently developed a novel cardiac phantom for dynamic SPECT validation and compared its performance against the GE Discovery NM 530c. We now report its use for validation of a new hybrid SPECT/CT System featuring advanced cadmium zinc telluride (CZT) technology in a ring array detector design (StarGuide™, GE HealthCare).</p><h3>Methods</h3><p>Our recently developed cardiac phantom with injected technetium-99m radiotracer was used to create physiological time activity curves (TACs) for the left ventricular (LV) cavity and the myocardium. The TACs allow the calculation of uptake rate (K1) and MBF. The StarGuide system was used to acquire and process the TACs, and these were compared to the TACs produced by the phantom and its mathematical model. Fifteen (15) experiments with different doses representing various MBF values were conducted, and a standard statistic tool was applied for significance.</p><h3>Results</h3><p>The TACs produced by the StarGuide system had a significant correlation (<i>p</i> &lt; 0.001) with the reference TACs generated by the phantom both for the LV (r = 0.94) and for the myocardium (r = 0.89). The calculated MBF difference between the system and the phantom was 0.14 ± 0.16 ml/min/g and the average relative absolute difference was 13.2 ± 8.1%. A coefficient of variance of ≤ 11% was observed for all MBF subranges. The regional uptake rate values were similar to the global one with a maximum difference of 5%.</p><h3>Conclusions</h3><p>Our newly developed dynamic cardiac phantom was used for validation of the dynamic hybrid SPECT/CT CZT-based system (StarGuide™, GE). The accuracy and precision of the system for assessing MBF values were high. The new StarGuide system can reliably perform dynamic SPECT acquisitions over a wide range of myocardial perfusion flow rates.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"38 11","pages":"919 - 926"},"PeriodicalIF":2.5,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12149-024-01966-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142103643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phantom test procedures for a new neuro-oncological amino acid PET tracer: [¹⁸F]fluciclovine.","authors":"Kaede Tsuzura, Kei Wagatsuma, Yuto Kamitaka, Kenta Miwa, Noriaki Miyaji, Takashi Kamiya, Noriyo Yokotsuka, Kenji Ishii","doi":"10.1007/s12149-024-01973-x","DOIUrl":"https://doi.org/10.1007/s12149-024-01973-x","url":null,"abstract":"<p><strong>Objective: </strong>Amino acid positron emission tomography (PET) examinations using anti-1-amino-3-[¹⁸F]-fluorocyclobutane-1-carboxylic acid ([¹⁸F]FACBC) were allowed for routine clinical use in July 2024. However, phantom test procedures for [¹⁸F]FACBC reconstruction parameters have not yet been established. The present study aimed to establish new phantom test procedures for [¹⁸F]FACBC brain PET imaging to determine optimal reconstruction parameters.</p><p><strong>Methods: </strong>Background (BG) activity as well as hot sphere and target-to-background ratios (TBRs) of [¹⁸F]FACBC were estimated based on brain activity and tumor-to-normal tissue ratios (TNR) in a Japanese clinical trial of [¹⁸F]FACBC. Phantom experiments proceeded under [¹⁸F]FACBC or L-[methyl-¹¹C]-methionine ([¹¹C]MET) conditions. The number of iterations and the Gaussian filter parameters were determined from the reconstruction parameters %contrast_mean and coefficients of variation (CVs) in ordered subset expectation maximization (OSEM) and time-of-flight (TOF) with or without point-spread-function (PSF) correction.</p><p><strong>Results: </strong>The amounts of activity in the hot spheres and BG were 1.1 and 5.5 kBq/mL, respectively, and the TBR was 5.0 at the start of acquisition. The %contrast_mean of all hot spheres was higher with [¹⁸F]FACBC than [¹¹C]MET, and %contrast_mean converged between 4 and 6 iterations in hot spheres with diameters < 10 mm. We used four iterations for OSEM + TOF and five for OSEM + TOF + PSF correction for [¹⁸F]FACBC and [¹¹C]MET images. The CV was higher for [¹⁸F]FACBC than [¹¹C]MET. The optimal sizes of Gaussian filters for OSEM + TOF and OSEM + TOF + PSF correction of image reconstruction were 5 mm for [¹⁸F]FACBC, and 4 and 3 mm, respectively, for [¹¹C]MET images.</p><p><strong>Conclusions: </strong>We estimated phantom activity and TBR based on brain activity in a Japanese clinical trial and established new phantom test procedures for [¹⁸F]FACBC. We recommend that the optimal reconstruction parameters for [¹⁸F]FACBC should be set to the same number of iterations as [¹¹C]MET and that the FWHM of Gaussian filter should have a few mm higher than [¹¹C]MET to reduce image noise from brain normal tissue.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142103642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel algorithm developed using machine learning and a J-ACCESS database can estimate defect scores from myocardial perfusion single-photon emission tomography images","authors":"Keisuke Kiso,&nbsp;Kenichi Nakajima,&nbsp;Yukitaka Nimura,&nbsp;Tsunehiko Nishimura","doi":"10.1007/s12149-024-01971-z","DOIUrl":"10.1007/s12149-024-01971-z","url":null,"abstract":"<div><h3>Background</h3><p>Stress myocardial perfusion single-photon emission computed tomography (SPECT) imaging (MPI) has been used to diagnose and predict the prognoses of patients with coronary artery disease (CAD). An ongoing multicenter collaboration established a Japanese database (J-ACCESS) in 2001 that includes a risk model and expert interpretations. The present study aimed to develop a novel algorithm using machine learning (ML) and resources from the J-ACCESS database to aid SPECT image interpretation.</p><h3>Methods</h3><p>We analyzed data from 1288 patients in J-ACCESS 3 and 4 databases. Three-dimensional (3D) stereoscopic images of left ventricular myocardial perfusion were reconstructed with linear transformation from the original short-axis data. Segments were extracted from U-Net, then features were extracted from each segment during the ML process. We estimated segmental scores based on weighted features obtained from fully connected layers. Correlations between segment scores interpreted by nuclear cardiology experts and estimated by ML were evaluated using a 17-segment model, summed stress (SSS), summed rest (SRS), and summed difference (SDS) scores, and ratios (%) of summed different scores (%SDS).</p><h3>Results</h3><p>The complete concordance rate of scores assessed by the experts and estimated by ML was 79.6%. The underestimated and overestimated rates were 10.3% and 10.0%, respectively. Associations between defect scores assessed by experts and ML were close, with correlation coefficients (<i>r</i>) of 0.923, 0.917, 0.842 and 0.853 for SSS, SRS, SDS, %SDS, respectively (<i>p</i> &lt; 0.0001 for all).</p><h3>Conclusions</h3><p>We created a new algorithm to estimate MPI scores using ML and the J-ACCESS database. This algorithm should provide accurate MPI interpretation even in facilities without specialist nuclear cardiologists, and might facilitate therapeutic decision-making and predict prognoses.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":"38 12","pages":"980 - 988"},"PeriodicalIF":2.5,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12149-024-01971-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142103641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Voxel-based dosimetry with integrated Y-90 PET/MRI and prediction of response of primary and metastatic liver tumors to radioembolization with Y-90 glass microspheres.","authors":"Burak Demir, Cigdem Soydal, Nuriye Ozlem Kucuk, Emre Can Celebioglu, Mehmet Sadık Bilgic, Digdem Kuru Oz, Atilla Halil Elhan, Kemal Metin Kir","doi":"10.1007/s12149-024-01974-w","DOIUrl":"https://doi.org/10.1007/s12149-024-01974-w","url":null,"abstract":"<p><strong>Purpose: </strong>In this study, we aimed to evaluate the response of the primary and metastatic liver tumors to radioembolization with ⁹⁰Y glass microspheres and investigate its correlations with dosimetric variables calculated with ⁹⁰Y PET/MRI.</p><p><strong>Methods: </strong>In this ambispective study, 44 patients treated with ⁹⁰Y glass microspheres and imaged with ⁹⁰Y PET/MRI were included for analysis. Dosimetric analysis was performed for every perfused lesion using dose-volume histograms. Response was assessed by comparing pre-treatment and follow-up total lesion glycolysis (TLG) values derived from ¹⁸F-FDG PET imaging. The relationship between ΔTLG and log-transformed dosimetric variables was analyzed with linear mixed effects regression models. ROC analyses were performed to compare discriminatory power of the variables in predicting response and complete response.</p><p><strong>Results: </strong>Regression and ROC analyses demonstrated that mean tumor dose and almost all D values were statistically significant predictors of treatment response and complete treatment response. Specifically, D60, D70 and D80 values exhibited significantly higher discriminatory power for predicting treatment response compared to the mean dose (D_mean) delivered to tumor. High specificity cut-off values to predict response were determined as 160.75 Gy for D_mean, 95.50 Gy for D60, 89 Gy for D70, and 59.50 Gy for D80. Similarly, high-specificity cut-off values to predict complete response were 262.75 Gy for D_mean, 173 Gy for D70, 140.5 Gy for D80, and 100 Gy for D90.</p><p><strong>Conclusion: </strong>In this study, we demonstrated that voxel-based dosimetry with post-treatment ⁹⁰Y PET/MRI can predict response to treatment. D60, D70 and D80 variables also did have greater discriminatory power compared to D_mean in prediction of response. In addition, we present high-specificity cut-offs to predict response (CR + PR) and complete response (CR) for both D_mean and several D variables derived from dose-volume histograms.</p>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142103644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}