scholarly journals 68Ga-NOTA-exendin-4 PET/CT in detection of occult insulinoma and evaluation of physiological uptake

2014 ◽  
Vol 42 (3) ◽  
pp. 531-532 ◽  
Author(s):  
Yaping Luo ◽  
Miao Yu ◽  
QingQing Pan ◽  
Wenming Wu ◽  
Taiping Zhang ◽  
...  
Keyword(s):  
Physiological Uptake ◽  
Pet Ct

Physiological uptake of 18F-FDG in the vertebral bone marrow in healthy adults on PET/CT imaging

2018 ◽  
Vol 59 (12) ◽  
pp. 1487-1493 ◽  
Author(s):  
Guohua Shen ◽  
Meng Liang ◽  
Minggang Su ◽  
Anren Kuang
Keyword(s):  
Bone Marrow ◽  
Vertebral Body ◽  
Cervical Vertebrae ◽  
Healthy Adults ◽  
Physiological Uptake ◽  
Vertebral Bone ◽  
Fdg Uptake ◽  
Pet Ct ◽  
Vertebral Bone Marrow ◽  
18F Fdg

Background 18F-fluorodeoxyglucose *Equal contributors. positron emission tomography/computed tomography (18F-FDG PET/CT) has proven to be a valuable imaging modality for the assessment of bone marrow condition. Purpose To investigate the physiological uptake of 18F-FDG in the vertebral bone marrow in healthy adults on PET/CT imaging, and correlate the appearance with clinical factors including gender, body mass index, and age. Material and Methods A total of 64 healthy individuals underwent PET/CT scan, and for each vertebral body, the mean and maximum standardized uptake value (SUVmean and SUVmax) were determined in the central slice of vertebral body on the transversal fused PET/CT image. For each individual, the FDG uptake of the four regions was obtained by averaging the SUVmean and SUVmax of the vertebrae in individual regions. Results The FDG uptake from thoracic to sacral vertebrae showed an upward trend first, then a downward trend, while that of cervical vertebrae was relatively stable. The SUVmax and SUVmean values of bone marrow in the old group (age ≥ 50 years) were significantly lower than those in the young group (age < 50 years) in all regions of the spine ( P < 0.05). FDG uptake of the whole spine showed significant negative correlation with age, and the strongest correlation was observed in lumbar spine (SUVmean: r = −0.364, P < 0.05; SUVmax: r = −0.344, P < 0.05). Conclusion FDG uptake showed a tendency to increase first then decrease from thoracic to sacral vertebrae while the tendency was not obvious in cervical vertebrae. In addition, the glycolytic metabolism of all the four regions decreased with advancing age.

Radiation exposure of patients during 68Ga-DOTATOC PET/CT examinations

2009 ◽  
Vol 48 (05) ◽  
pp. 201-207 ◽  
Author(s):  
K. Zöphel ◽  
R. Freudenberg ◽  
L. Oehme ◽  
M. Andreeff ◽  
G. Wunderlich ◽  
...  
Keyword(s):  
Pituitary Gland ◽  
Radiation Exposure ◽  
Somatostatin Receptor ◽  
Blood Pool ◽  
Biological Data ◽  
Whole Body ◽  
Physiological Uptake ◽  
Standardized Uptake Values ◽  
Pet Ct ◽  
Routine Clinical Setting

Summary Aim: Investigation of the biodistribution and calculation of dosimetry of Ga-68-DOTATOCfor patients imaged in the routine clinical setting for diagnosis or exclusion of neuroendocrine tumours. Patients, methods: Dynamic PET/CT-imaging (Biograph 16) was performed over 20 min in 14 patients (8 men, 6 women) after injection of (112 ± 22) MBq 68Ga-DOTATOC followed by whole body 3D-acquisition (8 bed positions, 3 or 4 min each) 30 min p.i. and 120 min p.i. Urinary tracer elimination was measured and blood activity was derived non-invasively from the blood pool of the heart. The relevant organs for dosimetry were spleen, kidneys, liver, adrenals, urinary bladder and pituitary gland. Dosimetry was performed using OLINDA/ EXM 1.0 software and specific organ uptake was expressed as standardized uptake values (SUVs). Results: Rapid physiological uptake of the radiotracer could be demonstrated in liver, spleen and kidneys, adrenals and pituitary gland (mean SUVs were 6, 20, 16, 10, and 4, respectively). Radiotracer elimination was exclusively via urine (16% of injected dose within 2h); no redistribution could be observed. The spleen and the kidneys received the highest radiation exposure (0.24 mSv/MBq, 0.22 mSv/MBq resp.), mean effective dose yielded 0.023 mSv/MBq. Conclusion: 68Ga-DOTATOC is used extensively for diagnosis of somatostatin receptor positive tumours because it has several advantages over the 111In-labelled ligand. The derived dosimetric values are lower than first approximations from the biological data of OctreoScan. The use of CT for transmission correction of the PET data delivers radiation exposure up to 1 mSv (low dose).

scholarly journals PET/CT analysis of 21 patients with breast cancer: physiological distribution of 18F-choline and diagnostic pitfalls

2018 ◽  
Vol 46 (8) ◽  
pp. 3138-3148 ◽  
Author(s):  
Fathinul Fikri Ahmad Saad ◽  
Mohd Hazeman Zakaria ◽  
Bahunu Appanna
Keyword(s):  
Breast Cancer ◽  
Premenopausal Women ◽  
Axial Skeleton ◽  
Left Breast ◽  
Whole Body ◽  
Appendicular Skeleton ◽  
Choline Uptake ◽  
Physiological Uptake ◽  
Positron Emission ◽  
Pet Ct

Objectives 18F-choline is a useful tracer for detecting tumours with high lipogenesis. Knowledge of its biodistribution pattern is essential to recognise physiological variants. The aim of this study was to describe the physiologic distribution of 18F-choline and pitfalls in patients with breast cancer. Methods Twenty-one consecutive patients with breast cancer (10 premenopausal and 11 postmenopausal women; mean age, 52.82 ± 10.71 years) underwent 18F-choline positron emission tomography (PET)/computed tomography (CT) for staging. Whole-body PET/CT was acquired after 40 minutes of 18F-choline uptake. Acquired PET images were measured semiquantitatively. Results All patients showed pitfalls unrelated to breast cancer. These findings were predominantly caused by physiological glandular uptake in the liver, spleen, pancreas, bowels, axial skeleton (85%-100%), inflammation and benign changes (4.76%), appendicular skeleton (4.76%–19.049%), and site contamination (61.9%). In <1%, a concomitant metastatic neoplasm was found. The breast showed higher physiological uptake in premenopausal compared with postmenopausal woman (18F-choline maximum standardised uptake values [g/dL] of the right breast = 2.04 ± 0.404 vs 1.59 ± 0.97 and left breast = 2.00 ± 0.56 vs 1.93 ± 1.28, respectively). Conclusion 18F-choline uptake was higher in premenopausal women. Physiological 18F-choline uptake was observed in many sites, representing possible pathologies.

scholarly journals 68Ga-DOTA-FAPI-04 PET/CT as a Promising Tool for Differentiating Ovarian Physiological Uptake: Preliminary Experience of Comparative Analysis With 18F-FDG

2021 ◽  
Vol 8 ◽  
Author(s):  
Qixin Wang ◽  
Songsong Yang ◽  
Wenxin Tang ◽  
Lin Liu ◽  
Yue Chen
Keyword(s):  
Ct Scanning ◽  
Pathological Changes ◽  
Physiological Uptake ◽  
Medicine Department ◽  
Promising Tool ◽  
Pet Ct ◽  
Significant Difference ◽  
Ovarian Diseases ◽  
Left And Right

Objectives: This study aimed to investigate the physiological distribution characteristics of 68Ga-DOTA-FAPI-04 in the ovary, and assess the feasibility of early diagnosis of primary ovarian disease with 68Ga-DOTA-FAPI-04 PET/CT.Methods: We retrospectively analyzed the data of patients who received 18F-FDG and 68Ga-DOTA-FAPI-04 PET/CT scanning in the Nuclear Medicine Department of our hospital within 3 days from September 2020 to January 2021. We selected the data in which ovaries showed abnormal FDG activity. Patients with abnormal ovarian FDG uptake with focus confirmed by pathological biopsy or clinical follow-up as pathological changes were excluded. The uptake of tracers (18F-FDG and 68Ga-FAPI) was semi-quantitatively analyzed.Results: This study included 14 patients (average age was 38.6). Physiological ovarian uptake was mostly unilateral, and there was no significant difference in SUVmax between the left and right sides (FDGt = 0.272, FAPIt = 0.592). The ovary SUVmax of FDG (4.89 ± 1.84) was statistically significantly higher than that of FAPI (1.53 ± 0.37). The Le/Li ratio on FDG is 3.38 ± 1.81, TBR is 5.81 ± 1.98, while the Le/Li ratio on FAPI is 3.57 ± 1.26, TBR is 0.94 ± 0.19.Conclusion: Our research shows that ovarian functional or pathological changes can be manifested as FDG avid, while 68Ga-DOTA-FAPI-04 has no physiological accumulation in the ovary and is not affected by the menstrual cycle. Therefore, 68Ga-DOTA-FAPI-04 has unique advantages in the diagnosis of ovarian diseases, and can identify them early and accurately.

scholarly journals Evaluating a Machine Learning Tool for the Classification of Pathological Uptake in Whole-Body PSMA-PET-CT Scans

Tomography ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 301-312
Author(s):  
Annette Erle ◽  
Sobhan Moazemi ◽  
Susanne Lütje ◽  
Markus Essler ◽  
Thomas Schultz ◽  
...  
Keyword(s):  
Machine Learning ◽  
Area Under The Curve ◽  
Ground Truth ◽  
Tracer Uptake ◽  
Whole Body ◽  
Clinical Environment ◽  
Physiological Uptake ◽  
Psma Pet ◽  
Pet Ct ◽  
Unseen Data

The importance of machine learning (ML) in the clinical environment increases constantly. Differentiation of pathological from physiological tracer-uptake in positron emission tomography/computed tomography (PET/CT) images is considered time-consuming and attention intensive, hence crucial for diagnosis and treatment planning. This study aimed at comparing and validating supervised ML algorithms to classify pathological uptake in prostate cancer (PC) patients based on prostate-specific membrane antigen (PSMA)-PET/CT. Retrospective analysis of 68Ga-PSMA-PET/CTs of 72 PC patients resulted in a total of 77 radiomics features from 2452 manually delineated hotspots for training and labeled pathological (1629) or physiological (823) as ground truth (GT). As the held-out test dataset, 331 hotspots (path.:128, phys.: 203) were delineated in 15 other patients. Three ML classifiers were trained and ranked to assess classification performance. As a result, a high overall average performance (area under the curve (AUC) of 0.98) was achieved, especially to detect pathological uptake (0.97 mean sensitivity). However, there is still room for improvement to detect physiological uptake (0.82 mean specificity), especially for glands. The ML algorithm applied to manually delineated lesions predicts hotspot labels with high accuracy on unseen data and may be an important tool to assist in clinical diagnosis.

scholarly journals FAPI-04 PET/CT Using [18F]AlF Labeling Strategy: Automatic Synthesis, Quality Control, and In Vivo Assessment in Patient

2021 ◽  
Vol 11 ◽  
Author(s):  
Xiao Jiang ◽  
Xiaoxiong Wang ◽  
Taipeng Shen ◽  
Yutang Yao ◽  
Meihua Chen ◽  
...  
Keyword(s):  
Quality Control ◽  
Ductal Carcinoma ◽  
Specific Activity ◽  
Ph Value ◽  
Radiochemical Yield ◽  
Ct Imaging ◽  
Physiological Uptake ◽  
Promising Alternative ◽  
Synthesis Time ◽  
Pet Ct

68Ga labeled FAPI is the current standard for FAPI-PET, but its batch activity is limited. [18F]AlF-NOTA-FAPI-04 is a promising alternative combining the advantages of a chelator-based radiolabeling method with the unique properties of fluorine-18. The objective of this study was to develop a quick automatic method for synthesis of [18F]AlF-NOTA-FAPI-04 using a AllinOne synthesis system, and perform PET imaging with [18F]AlF-NOTA-FAPI-04 on patients. [18F]AlF-NOTA-FAPI-04 was produced, and its quality control was conducted by HPLC equipped with a radioactive detector. [18F]AlF-NOTA-FAPI-04 PET/CT imaging was performed in normal BALB/c mice (n = 3) and 4T1 breast cancer models (n = 3) to determine its biodistribution. Then [18F]AlF-NOTA-FAPI-04 and 18F-fluorodeoxyglucose (FDG) PET/CT imaging were performed in an invasive ductal carcinoma patient (female, 54 years old). The synthesis time of [18F]AlF-NOTA-FAPI-04 was about 25 min, and the radiochemical yield was 26.4 ± 1.5% (attenuation correction, n = 10). The radiochemical purity was above 99.0% and was above 98.0% after 6 h. The product was colorless transparent solution with pH value of 7.0–7.5, and the specific activity was 49.41 ± 3.19 GBq/μmol. PET/CT imaging in mice showed that physiological uptake of [18F]AlF-NOTA-FAPI-04 was mainly in the biliary system and bladder, and [18F]AlF-NOTA-FAPI-04 highly concentrated in tumor xenografts. PET/CT imaging in the patient showed that [18F]AlF-NOTA-FAPI-04 obtained high tumor background ratio (TBR) value of 8.44 in segment V and VI, while TBR value was 2.55 by 18F-FDG. [18F]AlF-NOTA-FAPI-04 could be synthesized with high radiochemical yield and batch production by AllinOne module and show excellent diagnosis performance in cancer patients.

Sign in / Sign up

Export Citation Format

Share Document