Annals of Nuclear Medicine

BACKGROUND: The 5-hydroxytryptamine receptor (5-HTR) family includes seven classes of receptors. The 5-HT7 R is the newest member of this family and contributes to different physiological and pathological processes. As a pathology, glioblastoma multiform (GBM) overexpresses 5-HT7 R; hence, this study aims to develop radiolabeled aryl piperazine derivatives as 5-HT7 R imaging agents.  METHODS: Compounds 6 and 7 as 1-(3-nitropyridin-2-yl)piperazine derivatives were radiolabeled with fac-[99m Tc(CO)3 (H2 O)3 ]+ and 99m Tc(CO)3 -[6] and 99m Tc(CO)3 -[7] were obtained with high radiochemical purity (RCP > 94%)...

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OBJECTIVE: To verify the visibility of physiological 18 F-fluorodeoxyglucose (18 F-FDG) uptake in nuclei in and around the brainstem by a whole-body (WB) silicon photomultiplier positron emission tomography (SiPM-PET) scanner with point-spread function (PSF) reconstruction using various iteration numbers. METHODS: Ten healthy subjects (5 men, 5 women; mean age, 56.0 ± 5.0 years) who underwent 18 F-FDG PET/CT using a WB SiPM-PET scanner and magnetic resonance imaging (MRI) of the brain including a spin-echo three-dimensional sampling perfection with application-optimized contrasts using different flip angle evolutions fluid-attenuated inversion recovery (3D-FLAIR) and a 3D-T1 magnetization-prepared rapid gradient-echo (T1-MPRAGE) images were enrolled...

We focus on reviewing state-of-the-art developments of dedicated PET scanners with irregular geometries and the potential of different aspects of multifunctional PET imaging. First, we discuss advances in non-conventional PET detector geometries. Then, we present innovative designs of organ-specific dedicated PET scanners for breast, brain, prostate, and cardiac imaging. We will also review challenges and possible artifacts by image reconstruction algorithms for PET scanners with irregular geometries, such as non-cylindrical and partial angular coverage geometries and how they can be addressed...

No abstract text is available yet for this article.

OBJECTIVE: Silicon photomultiplier-based positron emission tomography/computed tomography (SiPM-PET/CT) has the superior spatial resolution to conventional PET/CT (cPET/CT). This head-to-head comparison study compared the images of physiological 18 F-fluorodeoxyglucose (FDG) accumulation in small-volume structures between SiPM-PET/CT and cPET/CT in patients scanned with both modalities, and we investigated whether the thresholds that are reported to be useful for differentiating physiological accumulations from malignant lesions can also be applied to SiPM-PET/CT...

OBJECTIVE: PSMA expression is seen in many solid tumours in addition to prostate cancer and several studies and case reports have shown PSMA expression and 68 Ga-PSMA imaging of hepatocellular carcinoma (HCC). Our prospective study evaluates the role of 68 Ga-PSMA in HCC patients and compares it to conventional imaging (CE-CT/MRI). METHODS: Patients with radiologically and/or histopathologically confirmed HCC were included and all had undergone serum alpha-fetoprotein (S...

OBJECTIVE: 2-[18 F]fluoro-2-deoxy-D-glucose positron emission tomography ([18 F]-FDG-PET) is a imaging modality that has been used to measure of glucose metabolism in the brain in Alzheimer's disease (AD). Clinically, decreased glucose uptake has been reported in the brain of AD, although the precise underlying mechanisms have not yet been elucidated. To elucidate the mechanisms of decreased [18 F]-FDG uptake in the AD by PET, [18 F]-FDG uptake in the brain of aged model mouse of AD was investigated using a dynamic autoradiography technique "bioradiography"...

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BACKGROUND: Two randomized clinical trials demonstrated the efficacy of prostate-specific membrane antigen (PSMA) radioligand therapy (PSMA RLT) in metastatic castration-resistant prostate cancer (mCRPC). While the VISION trial used criteria within PSMA PET/CT for inclusion, the TheraP trial used dual tracer imaging including FDG PET/CT. Therefore, we investigated whether the application of the VISION criteria leads to a benefit in overall survival (OS) or progression-free survival (PFS) for men with mCRPC after PSMA RLT...

Nuclear cardiology has long been used to identify myocardial ischemia for appropriate treatment strategies for stable coronary artery disease (CAD). After the Ischemia Trial, it is time to reevaluate the significance of ischemia assessment. Functional imaging continues to play pivotal role in detecting microcirculatory disturbances. PET provides a clear image of blood flow distribution and is useful for the quantitative evaluation of myocardial flow reserve (MFR), which plays an important role in predicting treatment strategies and improving prognosis in CAD...

Recently, positron emission tomography (PET) with fibroblast activation protein inhibitor (FAPI) has gained significant attention as an advanced tumor diagnostic imaging tool. FAPI PET has a promising potential owing to its ability to accurately depict most malignant tumors. It has an accuracy that is comparable to or surpassing the diagnostic accuracy of PET using 18 F-fluorodeoxyglucose (FDG). Moreover, FAPI PET can identify malignant lesions that may be inconclusive on FDG PET. Beyond its application in neoplastic disorders, there have been encouraging reports suggesting the utility of FAPI PET in non-neoplastic conditions such as respiratory or cardiac diseases...

OBJECTIVE: Compared with radiation therapy using photon beams, particle therapies, especially those using carbons, show a high relative biological effectiveness and low oxygen enhancement ratio. Using cells cultured under normoxic conditions, our group reported a greater suppressive effect on cell growth by carbon beams than X-rays, and the subsequent therapeutic effect can be predicted by the cell uptake amount of 3'-deoxy-3'-[18 F]fluorothymidine (18 F-FLT) the day after treatment. On the other hand, a hypoxic environment forms locally around solid tumors, influencing the therapeutic effect of radiotherapy...

OBJECTIVE: To evaluate the differences in FDG accumulation in arteries throughout the body between digital and standard PET/CT. METHODS: Forty-six people who had FDG-PET examinations with a digital PET/CT scanner for health screening between April 2020 and March 2021 and had previous examinations with a standard PET/CT scanner were the study participants. FDG accumulation in arteries throughout the body was visually assessed in each segment. Scan was considered positive when arterial FDG accumulation was equal to or greater than that of the liver...

No abstract text is available yet for this article.

OBJECTIVE: We aimed to develop deep learning classifiers for assessing therapeutic response on bone scans of patients with prostate cancer. METHODS: A set of 3791 consecutive bone scans coupled with their last previous scan (1528 patients) was evaluated. Bone scans were labeled as "progression" or "nonprogression" on the basis of clinical reports and image review. A 2D-convolutional neural network architecture was trained with three different preprocessing methods: 1) no preprocessing (Raw), 2) spatial normalization (SN), and 3) spatial and count normalization (SCN)...

OBJECTIVES: MotionFree® (AMF) is a data-driven respiratory gating (DDG) algorithm for image processing that has recently been introduced into clinical practice. The present study aimed to verify the accuracy of respiratory waveform and the effects of normal and irregular respiratory motions using AMF with the DDG algorithm. METHODS: We used a NEMA IEC body phantom comprising six spheres (37-, 28-, 22-, 17-, 13-, and 10 mm diameter) containing 18 F. The sphere-to-background ratio was 4:1 (21...

OBJECTIVE: The aim of this study was to investigate the potential value of dual tracers 18 F-FDG and 18 F-FES PET/CT in predicting response to Cyclin-Dependent 4/6 Kinase (CDK4/6) inhibitors combined with endocrine therapy for metastatic estrogen receptor (ER)-positive breast cancer patients. METHODS: This retrospective study enrolled 38 ER-positive metastatic breast cancer patients from our center who underwent both 18 F-FDG and 18 F-FES PET/CT scans within 1 month before CDK4/6 inhibitors combined with endocrine therapy...

OBJECTIVE: Our objective was to correlate staging PSMA PET imaging parameters to final histopathology. Second objective was to assess the performance of standard versus delayed PSMA PET to detect primary prostate tumor. METHODS: Thirty-one patients (mean age, 61.4 ± 8.2) who underwent radical prostatectomy and preoperative staging PSMA PET scans were included in the study. After defining dominant lesion in pathology, correlations with PET images were performed...

OBJECTIVE: To create the 3D convolutional neural network (CNN)-based system that can use whole-body [18 F]FDG PET for recurrence/post-therapy surveillance in ovarian cancer (OC). METHODS: In this study, 1224 image sets from OC patients who underwent whole-body [18 F]FDG PET/CT at Kowsar Hospital between April 2019 and May 2022 were investigated. For recurrence/post-therapy surveillance, diagnostic classification as cancerous, and non-cancerous and staging as stage III, and stage IV were determined by pathological diagnosis and specialists' interpretation...