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  1. Robson RE, Brunger MJ, Buckman SJ, Garcia G, Petrović ZLj, White RD
    Sci Rep, 2015 Aug 06;5:12674.
    PMID: 26246002 DOI: 10.1038/srep12674
    The kinetic theory of non-relativistic positrons in an idealized positron emission tomography PET environment is developed by solving the Boltzmann equation, allowing for coherent and incoherent elastic, inelastic, ionizing and annihilating collisions through positronium formation. An analytic expression is obtained for the positronium formation rate, as a function of distance from a spherical source, in terms of the solutions of the general kinetic eigenvalue problem. Numerical estimates of the positron range - a fundamental limitation on the accuracy of PET, are given for positrons in a model of liquid water, a surrogate for human tissue. Comparisons are made with the 'gas-phase' assumption used in current models in which coherent scattering is suppressed. Our results show that this assumption leads to an error of the order of a factor of approximately 2, emphasizing the need to accurately account for the structure of the medium in PET simulations.
    Matched MeSH terms: Positron-Emission Tomography/methods*
  2. Joshi SC, Pant I, Hamzah F, Kumar G, Shukla AN
    Indian J Cancer, 2008 12 30;45(4):137-41.
    PMID: 19112200
    Positron emission tomography (PET) has emerged as an important diagnostic tool in the management of lung cancers. Although PET is sensitive in detection of lung cancer, but FDG (2-deoxy-2- 18 fluro-D-glucose) is not tumor specific and may accumulate in a variety of nonmalignant conditions occasionally giving false positive result. Addition of CT to PET improves specificity foremost, but also sensitivity in tumor imaging. Thus, PET/CT fusion images are a more accurate test than either of its individual components and are probably also better than side-by-side viewing of images from both modalities. PET/CT fusion images are useful in differentiating between malignant and benign disease, fibrosis and recurrence, staging and in changing patient management to more appropriate therapy. With analysis and discussion it appears that PET/ CT fusion images have the potential to dramatically improve our ability to manage the patients with lung cancer and is contributing to our understanding of cancer cell biology and in development of new therapies.
    Matched MeSH terms: Positron-Emission Tomography/methods*
  3. Tooyama I, Yanagisawa D, Taguchi H, Kato T, Hirao K, Shirai N, et al.
    Ageing Res Rev, 2016 09;30:85-94.
    PMID: 26772439 DOI: 10.1016/j.arr.2015.12.008
    The formation of senile plaques followed by the deposition of amyloid-β is the earliest pathological change in Alzheimer's disease. Thus, the detection of senile plaques remains the most important early diagnostic indicator of Alzheimer's disease. Amyloid imaging is a noninvasive technique for visualizing senile plaques in the brains of Alzheimer's patients using positron emission tomography (PET) or magnetic resonance imaging (MRI). Because fluorine-19 ((19)F) displays an intense nuclear magnetic resonance signal and is almost non-existent in the body, targets are detected with a higher signal-to-noise ratio using appropriate fluorinated contrast agents. The recent introduction of high-field MRI allows us to detect amyloid depositions in the brain of living mouse using (19)F-MRI. So far, at least three probes have been reported to detect amyloid deposition in the brain of transgenic mouse models of Alzheimer's disease; (E,E)-1-fluoro-2,5-bis-(3-hydroxycarbonyl-4-hydroxy)styrylbenzene (FSB), 1,7-bis(4'-hydroxy-3'-trifluoromethoxyphenyl)-4-methoxycarbonylethyl-1,6-heptadiene3,5-dione (FMeC1, Shiga-Y5) and 6-(3',6',9',15',18',21'-heptaoxa-23',23',23'-trifluorotricosanyloxy)-2-(4'-dimethylaminostyryl)benzoxazole (XP7, Shiga-X22). This review presents the recent advances in amyloid imaging using (19)F-MRI, including our own studies.
    Matched MeSH terms: Positron-Emission Tomography/methods*
  4. Hassan H, Othman MF, Abdul Razak HR, Zakaria ZA, Ahmad Saad FF, Osman MA, et al.
    Molecules, 2022 Nov 17;27(22).
    PMID: 36432069 DOI: 10.3390/molecules27227969
    [18F]sodium fluoride ([18F]NaF) is recognised to be superior to [99mTc]-methyl diphosphate ([99mTc]Tc-MDP) and 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) in bone imaging. However, there is concern that [18F]NaF uptake is not cancer-specific, leading to a higher number of false-positive interpretations. Therefore, in this work, [18F]AlF-NOTA-pamidronic acid was prepared, optimised, and tested for its in vitro uptake. NOTA-pamidronic acid was prepared by an N-Hydroxysuccinimide (NHS) ester strategy and validated by liquid chromatography-mass spectrometry analysis (LC-MS/MS). Radiolabeling of [18F]AlF-NOTA-pamidronic acid was optimised, and it was ensured that all quality control analysis requirements for the radiopharmaceuticals were met prior to the in vitro cell uptake studies. NOTA-pamidronic acid was successfully prepared and radiolabeled with 18F. The radiolabel was prepared in a 1:1 molar ratio of aluminium chloride (AlCl3) to NOTA-pamidronic acid and heated at 100 °C for 15 min in the presence of 50% ethanol (v/v), which proved to be optimal. The preliminary in vitro results of the binding of the hydroxyapatite showed that [18F]AlF-NOTA-pamidronic acid was as sensitive as [18F]sodium fluoride ([18F]NaF). Normal human osteoblast cell lines (hFOB 1.19) and human osteosarcoma cell lines (Saos-2) were used for the in vitro cellular uptake studies. It was found that [18F]NaF was higher in both cell lines, but [18F]AlF-NOTA-pamidronic acid showed promising cellular uptake in Saos-2. The preliminary results suggest that further preclinical studies of [18F]AlF-NOTA-pamidronic acid are needed before it is transferred to clinical research.
    Matched MeSH terms: Positron-Emission Tomography/methods
  5. May IJ, Nowak AK, Francis RJ, Ebert MA, Dhaliwal SS
    J Med Imaging Radiat Oncol, 2024 Feb;68(1):57-66.
    PMID: 37898984 DOI: 10.1111/1754-9485.13592
    INTRODUCTION: Malignant pleural mesothelioma is difficult to prognosticate. F18-Fluorodeoxyglucose positron emission tomography (FDG PET) shows promise for response assessment but is confounded by talc pleurodesis. F18-Fluorothymidine (FLT) PET is an alternative tracer specific for proliferation. We compared the prognostic value of FDG and FLT PET and determined the influence of talc pleurodesis on these parameters.

    METHODS: Overall, 29 prospectively recruited patients had FLT PET, FDG PET and CT-scans performed prior to and post one chemotherapy cycle; 10 had prior talc pleurodesis. Patients were followed for overall survival. CT response was assessed using mRECIST. Radiomic features were extracted using the MiM software platform. Changes in maximum SUV (SUVmax), mean SUV (SUVmean), FDG total lesion glycolysis (TLG), FLT total lesion proliferation (TLP) and metabolic tumour volume (MTV) after one chemotherapy cycle.

    RESULTS: Cox univariate analysis demonstrated FDG PET radiomics were confounded by talc pleurodesis, and that percentage change in FLT MTV was predictive of overall survival. Cox multivariate analysis showed a 10% increase in FLT tumour volume corresponded with 9.5% worsened odds for overall survival (P = 0.028, HR = 1.095, 95% CI [1.010, 1.187]). No other variables were significant on multivariate analysis.

    CONCLUSION: This is the first prospective study showing the statistical significance of FLT PET tumour volumes for measuring mesothelioma treatment response. FLT may be better than FDG for monitoring mesothelioma treatment response, which could help optimise mesothelioma treatment regimes.

    Matched MeSH terms: Positron-Emission Tomography/methods
  6. Nordin AJ, Rossetti C, Rahim NA
    Eur. J. Nucl. Med. Mol. Imaging, 2009 May;36(5):882.
    PMID: 19296106 DOI: 10.1007/s00259-009-1107-z
    Matched MeSH terms: Positron-Emission Tomography/methods*
  7. Ling LL, Hsu CC, Yong CC, Elsarawy AM, Chan YC, Wang CC, et al.
    Int J Surg, 2019 Sep;69:124-131.
    PMID: 31386913 DOI: 10.1016/j.ijsu.2019.07.035
    BACKGROUND: Tumor histology affects outcome after liver transplantation (LT) for hepatocellular carcinoma (HCC). This study explores the association between F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and tumor histology in living donor liver transplantation (LDLT) recipients and their outcome.

    MATERIALS AND METHODS: Two hundred fifty-eight patients with primary liver tumors who underwent FDG-PET before LDLT were enrolled in this retrospective study. Unfavorable tumor histology was defined as primary liver tumor other than a well- or moderately differentiated HCC. Thirteen patients had unfavorable tumor histology, including 2 poorly differentiated HCC, 2 sarcomatoid HCC, 5 combined hepatocellular cholangiocarcinoma, 3 intrahepatic cholangiocarcinoma, and 1 hilar cholangiocarcinoma.

    RESULTS: FDG-PET positivity was significantly associated with unfavorable tumor histology (P < 0.001). Both FDG-PET positivity and unfavorable tumor histology were significant independent predictors of tumor recurrence and overall survival. In a subgroup analysis of patients with FDG-PET-positive tumors, unfavorable tumor histology was a significant independent predictor of tumor recurrence and overall survival. High FDG uptake (tumor to non-tumor uptake ratio ≥ 2) was a significant predictor of unfavorable tumor histology. Patients with high FDG uptake and/or unfavorable tumors had significantly higher 3-year cumulative recurrence rate (70.8% versus 26.2%, P = 0.004) and worse 3-year overall survival (34.1% versus 70.8%, P = 0.012) compared to those with low FDG uptake favorable tumors.

    CONCLUSIONS: The expression of FDG-PET is highly associated with histology of explanted HCC and predicts the recurrence. FDG-PET-positive tumors with high FDG uptake may be considered contraindication for LDLT due to high recurrence rate except when pathology proves favorable histology.

    Matched MeSH terms: Positron-Emission Tomography/methods*
  8. Cheng J, Wang H, Wei S, Mei J, Liu F, Zhang G
    Comput Biol Med, 2024 Mar;170:108000.
    PMID: 38232453 DOI: 10.1016/j.compbiomed.2024.108000
    Alzheimer's disease (AD) is a neurodegenerative disease characterized by various pathological changes. Utilizing multimodal data from Fluorodeoxyglucose positron emission tomography(FDG-PET) and Magnetic Resonance Imaging(MRI) of the brain can offer comprehensive information about the lesions from different perspectives and improve the accuracy of prediction. However, there are significant differences in the feature space of multimodal data. Commonly, the simple concatenation of multimodal features can cause the model to struggle in distinguishing and utilizing the complementary information between different modalities, thus affecting the accuracy of predictions. Therefore, we propose an AD prediction model based on de-correlation constraint and multi-modal feature interaction. This model consists of the following three parts: (1) The feature extractor employs residual connections and attention mechanisms to capture distinctive lesion features from FDG-PET and MRI data within their respective modalities. (2) The de-correlation constraint function enhances the model's capacity to extract complementary information from different modalities by reducing the feature similarity between them. (3) The mutual attention feature fusion module interacts with the features within and between modalities to enhance the modal-specific features and adaptively adjust the weights of these features based on information from other modalities. The experimental results on ADNI database demonstrate that the proposed model achieves a prediction accuracy of 86.79% for AD, MCI and NC, which is higher than the existing multi-modal AD prediction models.
    Matched MeSH terms: Positron-Emission Tomography/methods
  9. Ashhar Z, Yusof NA, Ahmad Saad FF, Mohd Nor SM, Mohammad F, Bahrin Wan Kamal WH, et al.
    Molecules, 2020 Jun 09;25(11).
    PMID: 32526838 DOI: 10.3390/molecules25112668
    Early diagnosis of bone metastases is crucial to prevent skeletal-related events, and for that, the non-invasive techniques to diagnose bone metastases that make use of image-guided radiopharmaceuticals are being employed as an alternative to traditional biopsies. Hence, in the present work, we tested the efficacy of a gallium-68 (68Ga)-based compound as a radiopharmaceutical agent towards the bone imaging in positron emitting tomography (PET). For that, we prepared, thoroughly characterized, and radiolabeled [68Ga]Ga-NODAGA-pamidronic acid radiopharmaceutical, a 68Ga precursor for PET bone cancer imaging applications. The preparation of NODAGA-pamidronic acid was performed via the N-Hydroxysuccinimide (NHS) ester strategy and was characterized using liquid chromatography-mass spectrometry (LC-MS) and tandem mass spectrometry (MSn). The unreacted NODAGA chelator was separated using the ion-suppression reverse phase-high performance liquid chromatography (RP-HPLC) method, and the freeze-dried NODAGA-pamidronic acid was radiolabeled with 68Ga. The radiolabeling condition was found to be most optimum at a pH ranging from 4 to 4.5 and a temperature of above 60 °C. From previous work, we found that the pamidronic acid itself has a good bone binding affinity. Moreover, from the analysis of the results, the ionic structure of radiolabeled [68Ga]Ga-NODAGA-pamidronic acid has the ability to improve the blood clearance and may exert good renal excretion, enhance the bone-to-background ratio, and consequently the final image quality. This was reflected by both the in vitro bone binding assay and in vivo animal biodistribution presented in this research.
    Matched MeSH terms: Positron-Emission Tomography/methods*
  10. Noraini AR, Gay E, Ferrara C, Ravelli E, Mancini V, Morra E, et al.
    Singapore Med J, 2009 Dec;50(12):1189-95.
    PMID: 20087557
    To establish the role of positron-emission tomography (PET)-computed tomography (CT) in post-transplant lymphoproliferative disorder (PTLD) patients, compared to conventional imaging (ultrasonography/CT/magnetic resonance imaging) in relation to its accuracy, sensitivity and specificity.
    Matched MeSH terms: Positron-Emission Tomography/methods*
  11. Abdul Jalil N, Abdul Rahim N, Md Shalleh N, Rossetti C
    Singapore Med J, 2008 Jul;49(7):e178-82.
    PMID: 18695852
    A majority of the clinical use of positron emission tomography (PET)-computed tomography (CT) is related to cancer management. Its application in evaluating inflammatory diseases and pyrexia of unknown origin is becoming popular. We reviewed the fluorine-18-fluorodeoxyglucose PET-CT findings of an 80-year-old woman with nonspecific clinical presentation consisting of generalised malaise, moderately high fever and weight loss. Prior CT and magnetic resonance imaging were not helpful in providing a clinical diagnosis. The diagnosis was Horton's arteritis, and the patient responded well to high-dose steroids.
    Matched MeSH terms: Positron-Emission Tomography/methods*
  12. Wong CS, Cheah FC
    J Pediatr Surg, 2012 Dec;47(12):2336-40.
    PMID: 23217901 DOI: 10.1016/j.jpedsurg.2012.09.029
    Cephalhematoma is normally a self-limiting condition affecting 1%-2% of live births, especially following instrumental forceps delivery. The sub-periosteal bleed is characteristically limited by the cranial sutures. Although benign in most instances, this condition may, in a small proportion of cases, be complicated by hyperbilirubinemia or scalp infection. We describe a case of cephalhematoma in a newborn infant infected with Escherichia coli resulting in an extensive deep seated scalp abscess. The infection was also systemic causing E. coli septicemia and initial assessment assumed local extension including bone and meningeal to cause skull osteomyelitis and meningitis respectively. Further investigations and multiple-modality imaging with ultrasound, CT scan and bone scintigraphy outlined the involvement as limited to the scalp, resulting in a shorter antibiotic treatment period and earlier discharge from hospital. The infant recovered well with parenteral antibiotics, saucerization of the abscess and a later skin grafting procedure.
    Matched MeSH terms: Positron-Emission Tomography/methods
  13. Roselt P, Cullinane C, Noonan W, Elsaidi H, Eu P, Wiebe LI
    Molecules, 2020 Dec 03;25(23).
    PMID: 33287202 DOI: 10.3390/molecules25235700
    Vitamin E, a natural antioxidant, is of interest to scientists, health care pundits and faddists; its nutritional and biomedical attributes may be validated, anecdotal or fantasy. Vitamin E is a mixture of tocopherols (TPs) and tocotrienols (T-3s), each class having four substitutional isomers (α-, β-, γ-, δ-). Vitamin E analogues attain only low concentrations in most tissues, necessitating exacting invasive techniques for analytical research. Quantitative positron emission tomography (PET) with an F-18-labeled molecular probe would expedite access to Vitamin E's biodistributions and pharmacokinetics via non-invasive temporal imaging. (R)-6-(3-[18F]Fluoropropoxy)-2,7,8-trimethyl-2-(4,8,12-trimethyltrideca-3,7,11-trien-1-yl)-chromane ([18F]F-γ-T-3) was prepared for this purpose. [18F]F-γ-T-3 was synthesized from γ-T-3 in two steps: (i) 1,3-di-O-tosylpropane was introduced at C6-O to form TsO-γ-T-3, and (ii) reaction of this tosylate with [18F]fluoride in DMF/K222. Non-radioactive F-γ-T-3 was synthesized by reaction of γ-T-3 with 3-fluoropropyl methanesulfonate. [18F]F-γ-T-3 biodistribution in a murine tumor model was imaged using a small-animal PET scanner. F-γ-T-3 was prepared in 61% chemical yield. [18F]F-γ-T-3 was synthesized in acceptable radiochemical yield (RCY 12%) with high radiochemical purity (>99% RCP) in 45 min. Preliminary F-18 PET images in mice showed upper abdominal accumulation with evidence of renal clearance, only low concentrations in the thorax (lung/heart) and head, and rapid clearance from blood. [18F]F-γ-T-3 shows promise as an F-18 PET tracer for detailed in vivo studies of Vitamin E. The labeling procedure provides acceptable RCY, high RCP and pertinence to all eight Vitamin E analogues.
    Matched MeSH terms: Positron-Emission Tomography/methods
  14. Vairavan R, Abdullah O, Retnasamy PB, Sauli Z, Shahimin MM, Retnasamy V
    Curr Med Imaging Rev, 2019;15(2):85-121.
    PMID: 31975658 DOI: 10.2174/1573405613666170912115617
    BACKGROUND: Breast carcinoma is a life threatening disease that accounts for 25.1% of all carcinoma among women worldwide. Early detection of the disease enhances the chance for survival.

    DISCUSSION: This paper presents comprehensive report on breast carcinoma disease and its modalities available for detection and diagnosis, as it delves into the screening and detection modalities with special focus placed on the non-invasive techniques and its recent advancement work done, as well as a proposal on a novel method for the application of early breast carcinoma detection.

    CONCLUSION: This paper aims to serve as a foundation guidance for the reader to attain bird's eye understanding on breast carcinoma disease and its current non-invasive modalities.

    Matched MeSH terms: Positron-Emission Tomography/methods
  15. Goodman KA, Ou FS, Hall NC, Bekaii-Saab T, Fruth B, Twohy E, et al.
    J Clin Oncol, 2021 09 01;39(25):2803-2815.
    PMID: 34077237 DOI: 10.1200/JCO.20.03611
    PURPOSE: To evaluate the use of early assessment of chemotherapy responsiveness by positron emission tomography (PET) imaging to tailor therapy in patients with esophageal and esophagogastric junction adenocarcinoma.

    METHODS: After baseline PET, patients were randomly assigned to an induction chemotherapy regimen: modified oxaliplatin, leucovorin, and fluorouracil (FOLFOX) or carboplatin-paclitaxel (CP). Repeat PET was performed after induction; change in maximum standardized uptake value (SUV) from baseline was assessed. PET nonresponders (< 35% decrease in SUV) crossed over to the alternative chemotherapy during chemoradiation (50.4 Gy/28 fractions). PET responders (≥ 35% decrease in SUV) continued on the same chemotherapy during chemoradiation. Patients underwent surgery at 6 weeks postchemoradiation. Primary end point was pathologic complete response (pCR) rate in nonresponders after switching chemotherapy.

    RESULTS: Two hundred forty-one eligible patients received Protocol treatment, of whom 225 had an evaluable repeat PET. The pCR rates for PET nonresponders after induction FOLFOX who crossed over to CP (n = 39) or after induction CP who changed to FOLFOX (n = 50) was 18.0% (95% CI, 7.5 to 33.5) and 20% (95% CI, 10 to 33.7), respectively. The pCR rate in responders who received induction FOLFOX was 40.3% (95% CI, 28.9 to 52.5) and 14.1% (95% CI, 6.6 to 25.0) in responders to CP. With a median follow-up of 5.2 years, median overall survival was 48.8 months (95% CI, 33.2 months to not estimable) for PET responders and 27.4 months (95% CI, 19.4 months to not estimable) for nonresponders. For induction FOLFOX patients who were PET responders, median survival was not reached.

    CONCLUSION: Early response assessment using PET imaging as a biomarker to individualize therapy for patients with esophageal and esophagogastric junction adenocarcinoma was effective, improving pCR rates in PET nonresponders. PET responders to induction FOLFOX who continued on FOLFOX during chemoradiation achieved a promising 5-year overall survival of 53%.

    Matched MeSH terms: Positron-Emission Tomography/methods*
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