Annals of Nuclear Medicine最新文献

{"title":"Improvement in the estimation of perfusable tissue fraction and myocardial flow reserve in the ischemic myocardial lesions using ECG-gated dynamic myocardial PET with 15O-water","authors":"Ayaka Maruo,&nbsp;Keiichi Magota,&nbsp;Yamato Munakata,&nbsp;Kenji Hirata,&nbsp;Chietsugu Katoh","doi":"10.1007/s12149-024-01913-9","DOIUrl":"10.1007/s12149-024-01913-9","url":null,"abstract":"<div><h3>Objective</h3><p>Perfusable tissue fraction (PTF) and myocardial flow reserve (MFR) from ¹⁵O-water dynamic positron emission tomography (PET) are parameters of myocardial viability. However, myocardial motion causes errors in these values. We aimed to develop accurate estimation of PTF and MFR in ischemic lesions using an electro-cardiogram (ECG)-gated dynamic myocardial PET with ¹⁵O-water.</p><h3>Methods</h3><p>Twenty-seven patients with ischemic heart disease were enrolled. All patients underwent percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). List mode 3D PET data and ECG signals were acquired using Philips Gemini TF64 instrument. For each scan, 500 MBq of ¹⁵O-water was infused slowly for 2 min, and the dynamic data were scanned for 6 min. Both non-gated dynamic images and ECG-gated diastolic dynamic images were reconstructed. On the myocardial PET images of each patient, the entire myocardial region of interest (ROI) was set and divided into 17 segments. Myocardial blood flow in the resting state (rest MBF), hyperemic state (stress MBF), PTF, and MFR in each segment were estimated from both non-gated and ECG-gated dynamic PET images. Coronary arteriograms were obtained for all patients. In total, 128 normal segments without stenosis and 50 ischemic segments with &gt; 90% stenosis were evaluated.</p><h3>Results</h3><p>In the ischemic myocardial segments, the PTF with ECG-gated PET was estimated as significantly lower than that with non-gated PET (0.63 ± 0.09 vs. 0.72 ± 0.08 [mL/mL], p &lt; 0.001). The ECG-gated PET estimated a significantly lower PTF in the ischemic segments than in the normal segments (0.63 ± 0.09 vs. 0.67 ± 0.07 [mL/mL], p &lt; 0.01). In the normal segments, the ECG-gated PET detected no significant difference in MFR compared with those from the non-gated PET (2.15 ± 0.76 vs. 2.24 ± 0.79, p = 0.28). However, in the ischemic myocardial segments, the MFR with ECG-gated PET was estimated as significantly lower than that with the non-gated PET (1.23 ± 0.29 vs. 1.69 ± 0.71, p &lt; 0.001). The ECG-gated PET presented a significantly higher inter-observer reproducibility of PTF and rest MBF than the non-gated PET (p &lt; 0.01). Neither stress MBF nor MFR yielded significant differences in inter-observer reproducibility between the ECG-gated and non-gated PET.</p><h3>Conclusions</h3><p>The ECG-gated dynamic ¹⁵O-water PET suppressed the myocardial motion effect and resulted in a lower PTF and MFR in ischemic myocardial lesions than the non-gated PET. The ECG-gated PET seemed to be better than the conventional non-gated dynamic PET for the detection of ischemic myocardial lesion.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140118609","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":"Flare phenomenon visualized by 99mTc-bone scintigraphy has prognostic value for patients with metastatic castration-resistant prostate cancer","authors":"Xue Zhang,&nbsp;Kenichi Nakajima,&nbsp;Atsushi Mizokami,&nbsp;Hiroyuki Horikoshi,&nbsp;Koshiro Nishimoto,&nbsp;Katsuyoshi Hashine,&nbsp;Hideyasu Matsuyama,&nbsp;Satoru Takahashi,&nbsp;Hiroshi Wakabayashi,&nbsp;Seigo Kinuya","doi":"10.1007/s12149-024-01914-8","DOIUrl":"10.1007/s12149-024-01914-8","url":null,"abstract":"<div><h3>Objective</h3><p>This study aimed to determine the prognostic value of the flare phenomenon in patients with metastatic castration-resistant prostate cancer (mCRPC) using the bone scan index (BSI) derived from ^99mTc-methylenediphosphonate (MDP) bone scintigraphy images.</p><h3>Methods</h3><p>We categorized 72 patients from the PROSTAT-BSI registry with mCRPC who were followed-up for 2 years after starting docetaxel chemotherapy to groups based on pre-chemotherapy BSI values of &lt; 1, 1–4, and &gt; 4. We assessed the effects of the flare phenomenon (defined as a &gt; 10% increase in the BSI within 3 months of starting chemotherapy, followed by &gt; 10% improvement within the next 3 months) on survival using Kaplan–Meier curves and Cox proportional hazard analyses.</p><h3>Results</h3><p>The flare phenomenon was found in 26 (36%) of the 72 patients. Prostate-specific antigen (PSA), alkaline phosphatase (ALP), and hemoglobin (Hb) levels steadily increased, then deteriorated in patients with and without flare, respectively. Elevated BSI and PSA values at 3 months after starting therapy and the absence of abiraterone or/and enzalutamide therapy led to poor 2-year overall survival (OS) in the group without flare. In contrast, no influence was noticeable in the group with flare. The results of multivariable analyses that included only factors associated with PSA and BSI showed that increased baseline BSI (hazard ratio [HR], 1.39; 95% confidence interval [CI], 1.04–1.86; <i>P</i> = 0.023) and PSA (HR, 7.15; 95% CI 2.13–24.04; <i>P</i> = 0.0015) values could be independent risk factors for patients with mCRPC without flare. However, these factors lost significance during flare. The risk for all-cause death was significantly higher among patients with BSI &gt; 4 without, than with flare. The results of univariable analyses indicated that flare positively impacted survival (HR, 0.24; 95% CI 0.06‒0.91; <i>P</i> = 0.035). Multivariable analysis did not identify any factors that could predict outcomes.</p><h3>Conclusion</h3><p>Favorable prognosis, with fewer disturbances from other factors such as the use of abiraterone or/and enzalutamide, PSA changes, and BSI, was attainable in cases when the mCRPC patient demonstrated flare phenomenon. Follow-up bone scintigraphy at least every 3 months could help to determine the prognosis of patients with bone metastasis of mCRPC.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11108890/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140118597","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":"Quantitative analysis of abdominal aortic blood flow by 99mTc-DTPA renal scintigraphy in patients with heart failure","authors":"Yue Li,&nbsp;Zhiqiang Yang,&nbsp;Pei Yin,&nbsp;Xian Gao,&nbsp;Lizhuo Li,&nbsp;Qingzhen Zhao,&nbsp;Yuzhi Zhen,&nbsp;Yu Wang,&nbsp;Chao Liu","doi":"10.1007/s12149-024-01912-w","DOIUrl":"10.1007/s12149-024-01912-w","url":null,"abstract":"<div><h3>Objective</h3><p>This study aimed to explore the characteristics of abdominal aortic blood flow in patients with heart failure (HF) using ^99mTc-diethylenetriaminepentaacetic acid (DTPA) renal scintigraphy. We investigated the ability of renal scintigraphy to measure the cardiopulmonary transit time and assessed whether the time-to-peak of the abdominal aorta (TTPa) can distinguish between individuals with and without HF.</p><h3>Methods</h3><p>We conducted a retrospective study that included 304 and 37 patients with and without HF (controls), respectively. All participants underwent ^99mTc-DTPA renal scintigraphy. The time to peak from the abdominal aorta’s first-pass time–activity curve was noted and compared between the groups. The diagnostic significance of TTPa for HF was ascertained through receiver operating characteristic (ROC) analysis and logistic regression. Factors influencing the TTPa were assessed using ordered logistic regression.</p><h3>Results</h3><p>The HF group displayed a significantly prolonged TTPa than controls (18.5 [14, 27] s vs. 11 [11, 13] s). Among the HF categories, HF with reduced ejection fraction (HFrEF) exhibited the longest TTPa compared with HF with mildly reduced (HFmrEF) and preserved EF (HFpEF) (25 [17, 36.5] s vs. 17 [15, 23] s vs. 15 [11, 17] s) (<i>P</i> &lt; 0.001). The ROC analysis had an area under the curve of 0.831, which underscored TTPa’s independent diagnostic relevance for HF. The diagnostic precision was enhanced as left ventricular ejection fraction (LVEF) declined and HF worsened. Independent factors for TTPa included the left atrium diameter, LVEF, right atrium diameter, velocity of tricuspid regurgitation, and moderate to severe aortic regurgitation.</p><h3>Conclusions</h3><p>Based on ^99mTc-DTPA renal scintigraphy, TTPa may be used as a straightforward and non-invasive tool that can effectively distinguish patients with and without HF.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140100906","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":"Impact of [11C]methionine PET with Bayesian penalized likelihood reconstruction on glioma grades based on new WHO 2021 classification","authors":"Kei Wagatsuma,&nbsp;Kensuke Ikemoto,&nbsp;Motoki Inaji,&nbsp;Yuto Kamitaka,&nbsp;Shoko Hara,&nbsp;Kaoru Tamura,&nbsp;Kenta Miwa,&nbsp;Kaede Tsuzura,&nbsp;Taisei Tsuruki,&nbsp;Noriaki Miyaji,&nbsp;Kenji Ishibashi,&nbsp;Kenji Ishii","doi":"10.1007/s12149-024-01911-x","DOIUrl":"10.1007/s12149-024-01911-x","url":null,"abstract":"<div><h3>Objective</h3><p>The uptake of [¹¹C]methionine in positron emission tomography (PET) imaging overlapped in earlier images of tumors. Bayesian penalized likelihood (BPL) reconstruction increases the quantitative values of tumors compared with conventional ordered subset-expectation maximization (OSEM). The present study aimed to grade glioma malignancy based on the new WHO 2021 classification using [¹¹C]methionine PET images reconstructed using BPL.</p><h3>Methods</h3><p>We categorized 32 gliomas in 28 patients as grades 2/3 (<i>n</i> = 15) and 4 (<i>n</i> = 17) based on the WHO 2021 classification. All [¹¹C]methionine images were reconstructed using OSEM + time-of-flight (TOF) and BPL + TOF (<i>β = </i>200). Maximum standardized uptake value (SUV_max) and tumor-to-normal tissue ratio (T/N_max) were measured at each lesion.</p><h3>Results</h3><p>The mean SUV_max was 4.65 and 4.93 in grade 2/3 and 6.38 and 7.11 in grade 4, and the mean T/N_max was 7.08 and 7.22 in grade 2/3 and 9.30 and 10.19 in grade 4 for OSEM and BPL, respectively. The BPL significantly increased these values in grade 4 gliomas. The area under the receiver operator characteristic (ROC) curve (AUC) for SUV_max was the highest (0.792) using BPL.</p><h3>Conclusions</h3><p>The BPL increased mean SUV_max and mean T/N_max in lesions with higher contrast such as grade 4 glioma. The discrimination power between grades 2/3 and 4 in SUV_max was also increased using [¹¹C]methionine PET images reconstructed with BPL.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140100905","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":"Correction: Radiation dosimetry and pharmacokinetics of the tau PET tracer florzolotau (18F) in healthy Japanese subjects","authors":"Masaomi Miyamoto,&nbsp;Chio Okuyama,&nbsp;Shinya Kagawa,&nbsp;Kuninori Kusano,&nbsp;Masaaki Takahashi,&nbsp;Keisuke Takahata,&nbsp;Ming-Kuei Jang,&nbsp;Hiroshi Yamauchi","doi":"10.1007/s12149-024-01917-5","DOIUrl":"10.1007/s12149-024-01917-5","url":null,"abstract":"","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10955007/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140048580","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":"The active papillary muscle sign in 18F-FDG PET/CT cardiac sarcoidosis exams and its relationship with myocardial suppression","authors":"Can Özütemiz,&nbsp;Yasemin Koksel,&nbsp;Jerry W. Froelich,&nbsp;Nathan Rubin,&nbsp;Maneesh Bhargava,&nbsp;Henri Roukoz,&nbsp;Rebecca Cogswell,&nbsp;Jeremy Markowitz,&nbsp;David M. Perlman,&nbsp;Daniel Steinberger","doi":"10.1007/s12149-024-01910-y","DOIUrl":"10.1007/s12149-024-01910-y","url":null,"abstract":"<div><h3>Objective</h3><p>Papillary muscle (PM) activity may demonstrate true active cardiac sarcoidosis (CS) or mimic CS in ¹⁸FDG-PET/CT if adequate myocardial suppression (MS) is not achieved. We aim to examine whether PM uptake can be used as a marker of failed MS and measure the rate of PM activity presence in active CS with different dietary preparations.</p><h3>Materials and methods</h3><p>We retrospectively reviewed PET/CTs obtained with three different dietary preparations. Diet-A: 24-h ketogenic diet with overnight fasting (<i>n</i> = 94); Diet-B: 18-h fasting (<i>n</i> = 44); and Diet-C: 72-h daytime ketogenic diet with 3-day overnight fasting (<i>n</i> = 98). Each case was evaluated regarding CS diagnosis (negative, positive, and indeterminant) and presence of PM activity. MaxSUV was measured from bloodpool, liver, and the most suppressed normal myocardium. Linear mixed-effects models were used to compare these factors between those with PM activity and those without.</p><h3>Results</h3><p>PM activity was markedly lower in the Diet-C group compared with others: Diet-C: 6 (6.1%), Diet-A: 36 (38.3%), and Diet-B: 26 (59.1%) (<i>p</i> &lt; <i>0.001).</i> Myocardium_MaxSUV was higher, and Myocardium_maxSUV/Bloodpool_maxSUV, Myocardium_maxSUV/Liver_maxSUV ratios were significantly higher in the cases with PM activity (<i>p</i> &lt; <i>0.001).</i> Among cases that used Diet-C and had PM activity, 66.7% were positive and 16.7% were indeterminate. If Diet-A or Diet-B was used, those with PM activity had a higher proportion of indeterminate cases (Diet-A: 61.1%, Diet-B: 61.5%) than positive cases (Diet-A: 36.1%, Diet-B: 38.5%).</p><h3>Conclusion</h3><p>Lack of PM activity can be a sign of appropriate MS. PM activity is less common with a specific dietary preparation (72-h daytime ketogenic diet with 3-day overnight fasting), and if it is present with this particular preparation, the likelihood that the case being true active CS might be higher than the other traditional dietary preparations.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140011998","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":"Nuclear medicine practice in Japan: a report of the ninth nationwide survey in 2022","authors":"Atsutaka Okizaki,&nbsp;Yoshihiro Nishiyama,&nbsp;Yoshitaka Inui,&nbsp;Hideki Otsuka,&nbsp;Kentaro Takanami,&nbsp;Masatoyo Nakajo,&nbsp;Koya Nakatani,&nbsp;Munenobu Nogami,&nbsp;Kenji Hirata,&nbsp;Yukito Maeda,&nbsp;Mana Yoshimura,&nbsp;Hiroshi Wakabayashi","doi":"10.1007/s12149-024-01905-9","DOIUrl":"10.1007/s12149-024-01905-9","url":null,"abstract":"&lt;div&gt;&lt;p&gt;Subcommittee on Survey of Nuclear Medicine Practice in Japan has performed a nationwide survey of nuclear medicine practice every 5 years since 1982 to survey contemporary nuclear medicine practice and its changes over the years. The subcommittee sent questionnaires, including the number and category of examinations as well as the kind of the radiopharmaceuticals during the 30 days of June 2022 to all nuclear medicine institutes in Japan. The total numbers of them for the year 2022 were estimated depends on the 1-month data. A total of 1095 institutes responded to the survey, including 364 positron emission tomography (PET) centers. The recovery rate was 90.6%. The number of gamma cameras installed was 1299 in total, with 2.5% decrease in 5 years. Dual-head cameras and hybrid SPECT/CT scanners accounted for 83.8% and 35.5%, respectively. The number of single-photon tracer studies in 2022 was 1.11 million which means increase in 2.7% in 5 years. Bone scintigraphy was a leading examination (31.0%), followed by myocardial scintigraphy (27.1%) and cerebral perfusion study (23.8%) in order. The percentage of SPECT studies showed an increase from 63.5% in previous survey to 66.8% in this survey. PET centers have also increased from 389 to 412, as compared with the previous one. One hundred and twenty-two PET centers have installed one or two in-house cyclotrons. Increasing trends of the PET studies were observed from 1992 to 2017, the trend changed and PET studies showed 1.5% decrease in 5 years. &lt;sup&gt;18&lt;/sup&gt;F-FDG accounted for 98.6% (610,497 examinations). PET examinations using &lt;sup&gt;11&lt;/sup&gt;C-methionine, &lt;sup&gt;13&lt;/sup&gt;N-NH&lt;sub&gt;3&lt;/sub&gt; and &lt;sup&gt;11&lt;/sup&gt;C-PIB have decreased, with 1624, 2146 and 525 examinations, respectively in 2022. The total number of nuclear medicine examination was eventually increased by 1.0%. Therapies for pheochromocytoma or paraganglioma (PPGL) with &lt;sup&gt;131&lt;/sup&gt;I-MIBG and for neuroendocrine tumor with &lt;sup&gt;177&lt;/sup&gt;Lu-DOTA-TATE were newly started, however, a total number of targeted radionuclide therapy was decreased by 17.7% because &lt;sup&gt;131&lt;/sup&gt;I-radioiodine and &lt;sup&gt;223&lt;/sup&gt;Ra targeted therapies were decreased and supply of some radioisotopes was discontinued. &lt;sup&gt;131&lt;/sup&gt;I-radioiodine targeted therapy showed a decrease in 5 years (− 15.9%), including 4099 patients for thyroid cancer. The number of out-patient thyroid bed ablation therapy with 1110 MBq of &lt;sup&gt;131&lt;/sup&gt;I was also decreased to 1015 per year. The number of admission rooms specialized for radionuclide targeted therapy increased from 157 to 160. The number of &lt;sup&gt;223&lt;/sup&gt;Ra targeted therapies for castration-resistant metastatic prostate cancer (mCRPC) was 1041 patients. This survey was performed during COVID-19 pandemic, however, total number of nuclear medicine examinations was almost same as previous survey (+ 1.0%). Radionuclide therapies with &lt;sup&gt;131&lt;/sup&gt;I-MIBG and &lt;sup&gt;177&lt;/sup&gt;Lu-DOTA-TATE were newly started, and new radionuclide therapy ","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139989148","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":"Properties of [18F]FAPI monitoring of acute radiation pneumonia versus [18F]FDG in mouse models","authors":"Mingyu Liu,&nbsp;An Yao,&nbsp;Zili Li,&nbsp;Jianping Zhang,&nbsp;Caiyue Ren,&nbsp;Yuyun Sun,&nbsp;Guang Ma,&nbsp;Yun Sun,&nbsp;Jingyi Cheng","doi":"10.1007/s12149-024-01903-x","DOIUrl":"10.1007/s12149-024-01903-x","url":null,"abstract":"<div><h3>Objective</h3><p>In this study, the uptake characteristics of [¹⁸F]fibroblast activation protein inhibitor (FAPI) molecular imaging probe were investigated in acute radiation pneumonia and lung cancer xenografted mice before and after radiation to assess the future applicability of [¹⁸F]FAPI positron emission tomography/computed tomography (PET/CT) imaging in early radiotherapy response.</p><h3>Methods</h3><p>Initially, the biodistribution of [¹⁸F]FAPI tracer in vivo were studied in healthy mice at each time-point. A comparison of [¹⁸F]FAPI and [¹⁸F]fluorodeoxyglucose (FDG) PET/CT imaging efficacy in normal ICR, LLC tumor-bearing mice was evaluated. A radiation pneumonia model was then investigated using a gamma counter, small animal PET/CT, and autoradiography. The uptake properties of [¹⁸F]FAPI in lung cancer and acute radiation pneumonia were investigated using autoradiography and PET/CT imaging in mice.</p><h3>Results</h3><p>The tumor area was visible in [¹⁸F]FAPI imaging and the tracer was swiftly eliminated from normal tissues and organs. There was a significant increase of [¹⁸F]FDG absorption in lung tissue after radiotherapy compared to before radiotherapy, but no significant difference of [¹⁸F]FAPI uptake under the same condition. Furthermore, both the LLC tumor volume and the expression of FAP-ɑ decreased after thorax irradiation. Correspondingly, there was no notable [¹⁸F]FAPI uptake after irradiation, but there was an increase of [¹⁸F]FDG uptake in malignancies and lungs.</p><h3>Conclusions</h3><p>The background uptake of [¹⁸F]FAPI is negligible. Moreover, the uptake of [¹⁸F]FAPI may not be affected by acute radiation pneumonitis compared to [¹⁸F]FDG, which may be used to more accurately evaluate early radiotherapy response of lung cancer with acute radiation pneumonia.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11016509/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139970783","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":"Simultaneous evaluation of brain metastasis and thoracic cancer using semiconductor 11C-methionine PET/CT imaging","authors":"Koichiro Kaneko,&nbsp;Michinobu Nagao,&nbsp;Kaori Ueda,&nbsp;Atsushi Yamamoto,&nbsp;Shuji Sakai","doi":"10.1007/s12149-024-01908-6","DOIUrl":"10.1007/s12149-024-01908-6","url":null,"abstract":"<div><h3>Objective</h3><p>To investigate the potential of whole-body digital ¹¹C-methionine (MET) PET/CT imaging for simultaneous evaluation of thoracic cancer patients suspected of local recurrence (LR) after stereotactic radiosurgery (SRS) for brain metastasis.</p><h3>Methods</h3><p>A total of 45 lung or breast cancer patients suspected of LR after SRS were investigated using brain and whole-body MET-PET/CT scans. We compared the tumor-to-normal ratio (TNR) and maximum standardized uptake values (SUVmax) between patients with LR and radiation necrosis (RN) and performed receiver operating characteristic (ROC) analyses. We also investigated associations among extracranial recurrence, intracranial recurrence, primary site, and initial treatment type.</p><h3>Results</h3><p>A total of 44 LR and 14 RN lesions were analyzed. In the ROC analyses for differentiating LR from RN, TNR showed higher area under the curve (AUC) (0.82) than SUVmax (0.79), and the cutoff TNR value (2.12) was higher than current cutoff values of conventional PET systems. The whole-body scans detected extracranial recurrences in 31.1% of the patients. Recurrence rates were not significantly correlated with existence of intracranial recurrence or primary site, but patients who underwent non-surgical treatment (consisting of stage III/ IV patients according to the Union for International Cancer Control TNM classification or small-cell lung cancer patients) showed significantly higher recurrence than the surgically treated patients (68.8% vs. 10.3%, <i>p</i> = 0.0001).</p><h3>Conclusion</h3><p>In digital MET-PET/CT imaging, TNR was a more useful parameter to differentiate LR from RN than SUVmax, and the cutoff value was higher than those with conventional PET systems. Additional whole-body scans could detect extracranial recurrence and would be especially useful for advanced thoracic cancer patients who underwent non-surgical treatment.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139929694","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 fully automatic deep learning-based method for segmenting regions of interest and predicting renal function in pediatric dynamic renal scintigraphy","authors":"Xueli Ji,&nbsp;Guohui Zhu,&nbsp;Jinyu Gou,&nbsp;Suyun Chen,&nbsp;Wenyu Zhao,&nbsp;Zhanquan Sun,&nbsp;Hongliang Fu,&nbsp;Hui Wang","doi":"10.1007/s12149-024-01907-7","DOIUrl":"10.1007/s12149-024-01907-7","url":null,"abstract":"<div><h3>Objective</h3><p>Accurate delineation of renal regions of interest (ROIs) is critical for the assessment of renal function in pediatric dynamic renal scintigraphy (DRS). The purpose of this study was to develop and evaluate a deep learning (DL) model that can fully automatically delineate renal ROIs and calculate renal function in pediatric ^99mTechnetium-ethylenedicysteine (^99mTc-EC) DRS.</p><h3>Methods</h3><p>This study retrospectively analyzed 1,283 pediatric DRS data at a single center from January to December 2018. These patients were divided into training set (<i>n</i> = 1027), validation set (<i>n</i> = 128), and testing set (<i>n</i> = 128). A fully automatic segmentation of ROIs (FASR) model was developed and evaluated. The pixel values of the automatically segmented ROIs were calculated to predict renal blood perfusion rate (BPR) and differential renal function (DRF). Precision, recall rate, intersection over union (IOU), and Dice similarity coefficient (DSC) were used to evaluate the performance of FASR model. Intraclass correlation (ICC) and Pearson correlation analysis were used to compare the consistency of automatic and manual method in assessing the renal function parameters in the testing set.</p><h3>Results</h3><p>The FASR model achieved a precision of 0.88, recall rate of 0.94, IOU of 0.83, and DSC of 0.91. In the testing set, the r values of BPR and DRF calculated by the two methods were 0.94 (<i>P</i> &lt; 0.01) and 0.97 (<i>P</i> &lt; 0.01), and the ICCs (95% confidence interval CI) were 0.94 (0.90—0.96) and 0.94 (0.91—0.96).</p><h3>Conclusion</h3><p>We propose a reliable and stable DL model that can fully automatically segment ROIs and accurately predict renal function in pediatric ^99mTc-EC DRS.</p></div>","PeriodicalId":8007,"journal":{"name":"Annals of Nuclear Medicine","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139904769","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}