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Recent progress in the applications of presynaptic dopaminergic positron emission tomography imaging in parkinsonism
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作者 Yujie Yang Xinyi Li +7 位作者 Jiaying Lu Jingjie Ge Mingjia Chen Ruixin Yao Mei Tian Jian Wang Fengtao Liu Chuantao Zuo 《Neural Regeneration Research》 SCIE CAS 2025年第1期93-106,共14页
Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of parkinsonism.... Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of parkinsonism.This review provides a comprehensive summary of the latest developments in the application of presynaptic dopaminergic positron emission tomography imaging in disorders that manifest parkinsonism.We conducted a thorough literature search using reputable databases such as PubMed and Web of Science.Selection criteria involved identifying peer-reviewed articles published within the last 5 years,with emphasis on their relevance to clinical applications.The findings from these studies highlight that presynaptic dopaminergic positron emission tomography has demonstrated potential not only in diagnosing and differentiating various Parkinsonian conditions but also in assessing disease severity and predicting prognosis.Moreover,when employed in conjunction with other imaging modalities and advanced analytical methods,presynaptic dopaminergic positron emission tomography has been validated as a reliable in vivo biomarker.This validation extends to screening and exploring potential neuropathological mechanisms associated with dopaminergic depletion.In summary,the insights gained from interpreting these studies are crucial for enhancing the effectiveness of preclinical investigations and clinical trials,ultimately advancing toward the goals of neuroregeneration in parkinsonian disorders. 展开更多
关键词 aromatic amino acid decarboxylase brain imaging dopamine transporter Parkinson’s disease PARKINSONISM positron emission tomography presynaptic dopaminergic function vesicle monoamine transporter type 2
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Impact of random and scattered coincidences from outside of field of view on positron emission tomography/computed tomography imaging with different reconstruction protocols
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作者 Mahak Osouli Alamdari Pardis Ghafarian +2 位作者 Arman Rahmim Mehrdad Bakhshayesh‑Karam Mohammad Reza Ay 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第12期40-52,共13页
Image quality in positron emission tomography(PET)is affected by random and scattered coincidences and reconstruction protocols.In this study,we investigated the effects of scattered and random coincidences from outsi... Image quality in positron emission tomography(PET)is affected by random and scattered coincidences and reconstruction protocols.In this study,we investigated the effects of scattered and random coincidences from outside the field of view(FOV)on PET image quality for different reconstruction protocols.Imaging was performed on the Discovery 690 PET/CT scanner,using experimental configurations including the NEMA phantom(a body phantom,with six spheres of different sizes)with a signal background ratio of 4:1.The NEMA phantom(phantom I)was scanned separately in a one-bed position.To simulate the effect of random and scatter coincidences from outside the FOV,six cylindrical phantoms with various diameters were added to the NEMA phantom(phantom II).The 18 emission datasets with mean intervals of 15 min were acquired(3 min/scan).The emission data were reconstructed using different techniques.The image quality parameters were evaluated by both phantoms.Variations in the signal-to-noise ratio(SNR)in a 28-mm(10-mm)sphere of phantom II were 37.9%(86.5%)for ordered-subset expectation maximization(OSEM-only),36.8%(81.5%)for point spread function(PSF),32.7%(80.7%)for time of flight(TOF),and 31.5%(77.8%)for OSEM+PSF+TOF,respectively,indicating that OSEM+PSF+TOF reconstruction had the lowest noise levels and lowest coefficient of variation(COV)values.Random and scatter coincidences from outside the FOV induced lower SNR,lower contrast,and higher COV values,indicating image deterioration and significantly impacting smaller sphere sizes.Amongst reconstruction protocols,OSEM+PSF+TOF and OSEM+PSF showed higher contrast values for sphere sizes of 22,28,and 37 mm and higher contrast recovery coefficient values for smaller sphere sizes of 10 and 13 mm. 展开更多
关键词 positron emission tomography/computed tomography(pet/CT) Random coincidences Scatter coincidences·Time of flight(TOF) Point spread function(PSF) Field of view(FOV) Noise equivalent count rate(NECR) Signal-toNoise ratio(SNR)
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IN VIVO VALIDATION OF DUAL-MODALITY SYSTEM FOR SIMULTANEOUS POSITRON EMISSION TOMOGRAPHY AND OPTICAL TOMOGRAPHIC IMAGING
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作者 XIN WANG BIN ZHANG +4 位作者 XU CAO FEI LIU SHUANGQUAN LIU BAOCI SHAN JING BAI 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2011年第2期165-171,共7页
We report on tests of combined positron emission tomography(PET)andfluorescence molecular tomography(FMT)imaging system for in vivo investigation on small animals.A nude mouse was inoculated with MD-MB-231 breast canc... We report on tests of combined positron emission tomography(PET)andfluorescence molecular tomography(FMT)imaging system for in vivo investigation on small animals.A nude mouse was inoculated with MD-MB-231 breast cancer cells which expressed redfluorescent protein(RFP).For FMT system,reflective illumination mode was adopted with full-angle data acquisition.[18F]-Fluorodeoxyglucose([18F]-FDG)was used as radioactive tracer for PET.Both data were acquired simultaneously and then reconstructed separately before fusion.Fluorescent tomography results showed exactly where the tumor was located while PET results offered more metabolic information.Results confirmed feasibility for tumor detection and showed superiority to single modality imaging. 展开更多
关键词 Dual-modality imaging positron emission tomography fluorescence molecular tomography
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Analytic time-of-flight positron emission tomography reconstruction: threedimensional case
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作者 Gengsheng L.Zeng Ya Li Qiu Huang 《Visual Computing for Industry,Biomedicine,and Art》 2020年第1期39-52,共14页
In a positron emission tomography(PET)scanner,the time-of-flight(TOF)information gives us rough event position along the line-of-response(LOR).Using the TOF information for PET image reconstruction is able to reduce i... In a positron emission tomography(PET)scanner,the time-of-flight(TOF)information gives us rough event position along the line-of-response(LOR).Using the TOF information for PET image reconstruction is able to reduce image noise.The state-of-the-art TOF PET image reconstruction uses iterative algorithms.This study introduces an analytic TOF PET algorithm that focuses on three-dimensional(3D)reconstruction.The proposed algorithm is in the form of backprojection filtering,in which the backprojection is performed first by using a time-resolution profile function,and then a 3D filter is applied to the backprojected image.For the list-mode data,the backprojection is carried out in the event-by-event fashion,and the timing resolution determined weighting function is used along the projection LOR.Computer simulations are carried out to verify the feasibility of the proposed algorithm. 展开更多
关键词 positron emission tomography TIME-OF-FLIGHT Analytic reconstruction
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Analytic time-of-flight positron emission tomography reconstruction: twodimensional case
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作者 Gengsheng L.Zeng Ya Li Qiu Huang 《Visual Computing for Industry,Biomedicine,and Art》 2019年第1期214-220,共7页
In a positron emission tomography(PET)scanner,the time-of-flight(TOF)information gives us rough event position along the line-of-response(LOR).Using the TOF information for PET image reconstruction is able to reduce i... In a positron emission tomography(PET)scanner,the time-of-flight(TOF)information gives us rough event position along the line-of-response(LOR).Using the TOF information for PET image reconstruction is able to reduce image noise.The state-of-the-art TOF PET image reconstruction uses iterative algorithms.Analytical image reconstruction algorithm exits for TOF PET which emulates the iterative Landweber algorithm.This paper introduces such an algorithm,focusing on two-dimensional(2D)reconstruction.The proposed algorithm is in the form of backprojection filtering,in which the backprojection is performed first,and then a 2D filter is applied to the backprojected image.For the list-mode data,the backprojection is carried out in the event-by-event fashion,and a profile function may be used along the projection LOR.The 2D filter depends on the TOF timing resolution as well as the backprojection profile function.In order to emulate the iterative algorithm effects,a Fourier-domain window function is suggested.This window function has a parameter,k,which corresponds to the iteration number in an iterative algorithm. 展开更多
关键词 positron emission tomography TIME-OF-FLIGHT Analytic reconstruction
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Clinical relevance of fluorodeoxyglucose positron emission tomography/computed tomography and magnifying endoscopy with narrow band imaging in decision-making regarding the treatment strategy for esophageal squamous cell carcinoma 被引量:7
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作者 Kazuhiro Toriyama Masahiro Tajika +14 位作者 Tsutomu Tanaka Makoto Ishihara Yutaka Hirayama Sachiyo Onishi Nobumasa Mizuno Takamichi Kuwahara Nozomi Okuno Shinpei Matsumoto Eiichi Sasaki Tetsuya Abe Yasushi Yatabe Kazuo Hara Keitaro Matsuo Tsuneo Tamaki Yasumasa Niwa 《World Journal of Gastroenterology》 SCIE CAS 2019年第46期6767-6780,共14页
BACKGROUND Recent advances in endoscopic technology,especially magnifying endoscopy with narrow band imaging(ME-NBI)enable us to detect superficial esophageal squamous cell carcinoma(ESCC),but determining the appropri... BACKGROUND Recent advances in endoscopic technology,especially magnifying endoscopy with narrow band imaging(ME-NBI)enable us to detect superficial esophageal squamous cell carcinoma(ESCC),but determining the appropriate method of resection,endoscopic resection(ER)vs surgical resection,is often challenging.Recently,several studies have reported that 18F-fluorodeoxyglucose positron emission tomography(FDG-PET)is a useful indicator for decision-making regarding treatment for superficial ESCC.Although,there are not enough reports on association between FDG-PET uptake and clinicopathological characteristics of superficial ESCC.And,there are not enough reports on evaluating the usefulness of combination of FDG-PET and ME-NBI for determining the treatment strategy for superficial ESCC.This study evaluated clinical relevance of FDG-PET and ME-NBI in decision-making regarding the treatment strategy for ESCC.AIM To investigate the association between FDG uptake and the clinicopathological characteristics of superficial ESCC and its usefulness of combination of FDG-PET and ME-NBI for determining the treatment strategy for superficial ESCC.METHODS A database of all patients with superficial ESCC who had undergone both MENBI and FDG-PET for pre-treatment staging at Aichi Cancer Center Hospital between January 2008 and November 2018 was retrospectively analyzed.FDG uptake was defined positive or negative whether the primary lesion was visualized or could be distinguished from the background,or not.The invasion depth of ESCC was classified according to the Japan Esophageal Society.Primary endpoint is to evaluate the association between FDG uptake and clinicopathological characteristics of superficial ESCC.Secondary endpoint is to investigate the efficacy of combination of FDG-PET and ME-NBI for determining the treatment strategy for superficial ESCC.RESULTS A total of 82 lesions in 82 patients were included.FDG-PET showed positive uptake in 29(35.4%)lesions.Univariate analysis showed that uptake of FDG-PET had significant correlations with circumferential extension(P=0.014),pathological depth of tumor invasion(P<0.001),infiltrative growth pattern(P<0.001),histological grade(P=0.002),vascular invasion(P=0.001),and lymphatic invasion(P<0.001).On multivariate analysis,only depth of tumor invasion was independently correlated with FDG-PET/computed tomography visibility(P=0.018).The sensitivity,specificity,positive predictive value(PPV),negative predictive value(NPV),and accuracy of Type B2 in ME-NBI for the invasion depth of T1a muscularis mucosae and T1b upper submucosal layer were 68.4%/79.4%/50.0%/89.3%/76.8%,respectively,and those of Type B3 for the depth of T1b middle and deeper submucosal layers(SM2 and SM3)were 46.7%/100%/100%/89.3%/90.2%,respectively.On the other hand,those of FDGPET for SM2 and SM3 were 93.3%/77.6%/48.2%/98.1%/80.5%,respectively,whereas,if the combination of positive FDG uptake and type B2 and B3 was defined as an indicator for radical esophagectomy or definitive chemoradiotherapy,the sensitivity,specificity,PPV,NPV,and accuracy were 78.3%/91.5%/78.3%/91.5%/87.8%,respectively.CONCLUSION FDG uptake was correlated with the invasion depth of superficial ESCC.Combined use of FDG-PET and ME-NBI,especially with the microvascular findings of Type B2 and B3,is useful to determine whether ER is indicated for the lesion. 展开更多
关键词 ^18F-fluorodeoxyglucose positron emission tomography Magnifying endoscopy Narrow band imaging Superficial esophageal cancer Squamous cell carcinoma Treatment strategy
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Imaging plaque inflammation in asymptomatic cocaine addicted individuals with simultaneous positron emission tomography/magnetic resonance imaging 被引量:2
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作者 Keren Bachi Venkatesh Mani +4 位作者 Audrey E Kaufman Nadia Alie Rita Z Goldstein Zahi A Fayad Nelly Alia-Klein 《World Journal of Radiology》 CAS 2019年第5期62-73,共12页
BACKGROUND Chronic cocaine use is associated with stroke, coronary artery disease and myocardial infarction, resulting in severe impairments or sudden mortality. In the absence of clear cardiovascular symptoms, indivi... BACKGROUND Chronic cocaine use is associated with stroke, coronary artery disease and myocardial infarction, resulting in severe impairments or sudden mortality. In the absence of clear cardiovascular symptoms, individuals with cocaine use disorder (iCUD) seeking addiction treatment receive mostly psychotherapy and psychiatric pharmacotherapy, with no attention to vascular disease (i.e., atherosclerosis). Little is known about the pre-clinical signs of cardiovascular risk in iCUD and early signs of vascular disease are undetected in this underserved population. AIM To assess inflammation, plaque burden and plaque composition in iCUD aiming to detect markers of atherosclerosis and vascular disease. METHODS The bilateral carotid arteries were imaged with positron emission tomography/magnetic resonance imaging (PET/MRI) in iCUD asymptomatic for cardiovascular disease, healthy controls, and individuals with cardiovascular risk. PET with 18F-fluorodeoxyglucose (18F-FDG) evaluated vascular inflammation and 3-D dark-blood MRI assessed plaque burden including wall area and thickness. Drug use and severity of addiction were assessed with standardized instruments. RESULTS The majority of iCUD and controls had carotid FDG-PET signal greater than 1.6 but lower than 3, indicating the presence of mild to moderate inflammation. However, the MRI measure of wall structure was thicker in iCUD as compared to the controls and cardiovascular risk group, indicating greater carotid plaque burden. iCUD had larger wall area as compared to the healthy controls but not as compared to the cardiovascular risk group, indicating structural wall similarities between the non-control study groups. In iCUD, wall area correlated with greater cocaine withdrawal and craving. CONCLUSION These preliminary results show markers of carotid artery disease burden in cardiovascular disease-asymptomatic iCUD. Broader trials are warranted to develop protocols for early detection of cardiovascular risk and preventive intervention in iCUD. 展开更多
关键词 3-D dark-blood magnetic RESONANCE imaging 18F-fluorodeoxyglucose positron emission tomography Simultaneous positron emission tomography Magnetic RESONANCE Substance use disorder COCAINE addiction Atherosclerosis PLAQUE burden Vascular INFLAMMATION
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Serial Brain Positron Emission Tomography Fused to Magnetic Resonance Imaging in Post-Infectious and Autoantibody-Associated Autoimmune Encephalitis 被引量:3
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作者 David S. Younger 《World Journal of Neuroscience》 2019年第3期153-156,共4页
Serial positron emission tomography fused to magnetic resonance imaging showed progression of GAD65 autoimmune encephalitis.
关键词 GAD65 POST-TREATMENT LYME disease AUTOIMMUNE ENCEPHALITIS positron emission tomography Magnetic Resonance imaging
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Positron emission tomography and magnetic resonance imaging combined with computed tomography in tumor volume delineation: A case report 被引量:1
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作者 Qi-Ping Zhou Yu-Hua Zhao Lei Gao 《World Journal of Clinical Cases》 SCIE 2022年第1期249-253,共5页
BACKGROUND Accurate delineation of the target area for patients with hypopharyngeal cancer is the key to achieving an ideal radiotherapy effect.Since computed tomography(CT)alone can no longer meet the treatment needs... BACKGROUND Accurate delineation of the target area for patients with hypopharyngeal cancer is the key to achieving an ideal radiotherapy effect.Since computed tomography(CT)alone can no longer meet the treatment needs,fusing CT images with magnetic resonance imaging(MRI)or positron emission tomography(PET)images can overcome the disadvantages of CT.Herein,we present a clinical case of hypopharyngeal cancer to delineate the tumor volume using combined MRI-CT and PET-CT fusion images to examine if they could accurately cover the tumor volume.CASE SUMMARY A 67-year-old male patient with hypopharyngeal carcinoma could not tolerate chemotherapy and surgery due to complicated health issues such as diabetic nephropathy and other underlying diseases.After multidisciplinary consultations,clinicians eventually agreed to undergo radiotherapy to control the progression of his tumor.He was examined by CT,MRI,and 18-fluorodeoxyglucose-PET for treatment planning,and CT images were fused with PET and MRI images while delineating tumor volume.CONCLUSION The image fusion of MRI-CT and PET-CT has both advantages and disadvantages.Compared with CT images alone,the combination of MRI-CT and PET-CT fusion images can precisely cover the gross tumor volume in hypopharyngeal carcinoma and avoid overestimation or incomplete coverage of tumor volume. 展开更多
关键词 Hypopharyngeal carcinoma Computed tomography Magnetic resonance imaging positron emission tomography image fusion Tumor volume delineation Case report
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Computed tomography, magnetic resonance imaging, and Fdeoxyglucose positron emission computed tomography/computed tomography findings of alveolar soft part sarcoma with calcification in the thigh: A case report 被引量:1
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作者 Zeng-Jie Wu Tian-Tian Bian +3 位作者 Xiao-Hong Zhan Cheng Dong Yan-Li Wang Wen-Jian Xu 《World Journal of Clinical Cases》 SCIE 2020年第15期3349-3354,共6页
BACKGROUND Alveolar soft part sarcoma(ASPS)is an extremely rare malignant sarcoma,accounting for less than 1%of all soft-tissue sarcomas.However,limited information is available on multimodal imaging[computed tomograp... BACKGROUND Alveolar soft part sarcoma(ASPS)is an extremely rare malignant sarcoma,accounting for less than 1%of all soft-tissue sarcomas.However,limited information is available on multimodal imaging[computed tomography(CT),magnetic resonance imaging(MRI),and positron emission computed tomography/computed tomography(PET/CT)]of ASPS.CASE SUMMARY This study reports a case of a 35-year-old female patient with ASPS of the left thigh with lung metastasis.The patient presented with a 1-year history of a palpable mass in the lower extremity,which exhibited rapid growth for 3 wk.CT,MRI,and F-deoxyglucose PET/CT examinations were performed.CT showed a slightly hypodense or isodense mass with patchy calcifications.On MRI examination,the mass manifested hyperintensity on T1-weighted,T2-weighted,and diffusion-weighted images with some signal voids.PET/CT images demonstrated an intensely hypermetabolic mass in the left thigh and hypermetabolic nodules in lungs.CONCLUSION ASPS should be considered as a possible diagnosis when a slow-growing mass is detected in the soft tissue of the extremities,with hyperintensity and numerous signal voids on T1-weighted,T2-weighted,and diffusion-weighted images and intense F-deoxyglucose uptake on PET/CT.ASPS can have calcifications on CT. 展开更多
关键词 Alveolar soft part sarcoma CALCIFICATION Magnetic resonance imaging positron emission computed tomography/computed tomography Case report
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Utility of positron emission tomography-magnetic resonance imaging in musculoskeletal imaging
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作者 Ammar A Chaudhry Maryam Gul +3 位作者 Elaine Gould Mathew Teng Kevin Baker Robert Matthews 《World Journal of Radiology》 CAS 2016年第3期268-274,共7页
Differentiation between neoplastic and nonneoplastic conditions magnetic resonance imaging(MRI) has established itself as one of the key clinical tools in evaluation of musculoskeletal pathology. However, MRI still ha... Differentiation between neoplastic and nonneoplastic conditions magnetic resonance imaging(MRI) has established itself as one of the key clinical tools in evaluation of musculoskeletal pathology. However, MRI still has several key limitations which require supplemental information from additional modalities to complete evaluation of various disorders. This has led to the development hybrid positron emission tomography(PET)-MRI which is rapidly evolving to address key clinical questions by using the morphological strengths of MRI and functional information of PET imaging. In this article, we aim to review physical principles and techniques of PET-MRI and discuss clinical utility of functional information obtained from PET imaging and structural information obtained from MRI imaging for the evaluation of musculoskeletal pathology. More specifically, this review highlights the role of PET-MRI in musculoskeletal oncology including initial diagnosis and staging, treatment planning and posttreatment follow-up. Also we will review utility of PET-MRI in evaluating musculoskeletal infections(especially in the immunocompromised and diabetics) and inflammatory condition. Additionally, common pitfalls of PET-MRI will be addressed. 展开更多
关键词 MAGNETIC RESONANCE imagING Osteosarcoma positron emission tomography-magnetic RESONANCE imagING Osteomyelitis positron emission tomographycomputed tomography positron emission tomography Multiple myeloma Lymphoma
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Imaging pancreatic islet cells by positron emission tomography
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作者 Junfeng Li Johann Karunananthan +1 位作者 Bradley Pelham Fouad Kandeel 《World Journal of Radiology》 CAS 2016年第9期764-774,共11页
It was estimated that every year more than 30000 persons in the United States- approximately 80 people per day- are diagnosed with type 1 diabetes(T1D). T1 D is caused by autoimmune destruction of the pancreatic islet... It was estimated that every year more than 30000 persons in the United States- approximately 80 people per day- are diagnosed with type 1 diabetes(T1D). T1 D is caused by autoimmune destruction of the pancreatic islet(β cells) cells. Islet transplantation has become a promising therapy option for T1 D patients, while the lack of suitable tools is difficult to directly evaluate of the viability of the grafted islet over time. Positron emission tomography(PET) as an important non-invasive methodology providing high sensitivity and good resolution, is able to accurate detection of the disturbed biochemical processes and physiological abnormality in living organism. The successful PET imaging of islets would be able to localize the specific site where transplanted islets engraft in the liver, and to quantify the level of islets remain alive and functional over time. This information would be vital to establishing and evaluating the efficiency of pancreatic islet transplantation. Many novel imaging agents have been developed to improve the sensitivity and specificity of PET islet imaging. In this article, we summarize the latest developments in carbon-11, fluorine-18, copper-64, and gallium-68 labeled radioligands for the PET imaging of pancreatic islet cells. 展开更多
关键词 DIABETES PANCREATIC ISLET cells positron emission tomography imagING tracers
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Simultaneous whole body ^(18)F-fluorodeoxyglucose positron emission tomography magnetic resonance imaging for evaluation of pediatric cancer: Preliminary experience and comparison with ^(18)F-fluorodeoxyglucose positron emission tomography computed tomogra
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作者 Brian S Pugmire Alexander R Guimaraes +8 位作者 Ruth Lim Alison M Friedmann Mary Huang David Ebb Howard Weinstein Onofrio A Catalano Umar Mahmood Ciprian Catana Michael S Gee 《World Journal of Radiology》 CAS 2016年第3期322-330,共9页
AIM: To describe our preliminary experience with simultaneous whole body ^(18)F-fluorodeoxyglucose(^(18)F-FDG)positron emission tomography and magnetic resonance imaging(PET-MRI) in the evaluation of pediatric oncolog... AIM: To describe our preliminary experience with simultaneous whole body ^(18)F-fluorodeoxyglucose(^(18)F-FDG)positron emission tomography and magnetic resonance imaging(PET-MRI) in the evaluation of pediatric oncology patients.METHODS: This prospective, observational, singlecenter study was Health Insurance Portability and Accountability Act-compliant, and institutional review board approved. To be eligible, a patient was required to:(1) have a known or suspected cancer diagnosis;(2) be under the care of a pediatric hematologist/oncologist; and(3) be scheduled for clinically indicated ^(18)F-FDG PETCT examination at our institution. Patients underwent PET-CT followed by PET-MRI on the same day. PET-CT examinations were performed using standard department protocols. PET-MRI studies were acquired with an integrated 3 Tesla PET-MRI scanner using whole body T1 Dixon, T2 HASTE, EPI diffusion-weighted imaging(DWI) and STIR sequences. No additional radiotracer was given for the PET-MRI examination. Both PET-CT and PETMRI examinations were reviewed by consensus by two study personnel. Test performance characteristics of PETMRI, for the detection of malignant lesions, including FDG maximum standardized uptake value(SUVmax) and minimum apparent diffusion coefficient(ADCmin), were calculated on a per lesion basis using PET-CT as a reference standard.RESULTS: A total of 10 whole body PET-MRI exams were performed in 7 pediatric oncology patients. The mean patient age was 16.1 years(range 12-19 years) including 6 males and 1 female. A total of 20 malignant and 21 benign lesions were identified on PET-CT. PET-MRI SUVmax had excellent correlation with PET-CT SUVmax for both benign and malignant lesions(R = 0.93). PETMRI SUVmax > 2.5 had 100% accuracy for discriminating benign from malignant lesions using PET-computed tomography(CT) reference. Whole body DWI was also evaluated: the mean ADCmin of malignant lesions(780.2 + 326.6) was significantly lower than that of benign lesions(1246.2 + 417.3; P = 0.0003; Student's t test). A range of ADCmin thresholds for malignancy were evaluated, from 0.5-1.5 × 10^(-3) mm^2/s. The 1.0 × 10^(-3) ADCmin threshold performed best compared with PETCT reference(68.3% accuracy). However, the accuracy of PET-MRI SUVmax was significantly better than ADCmin for detecting malignant lesions compared with PET-CT reference(P < 0.0001; two-tailed Mc Nemar's test).CONCLUSION: These results suggest a clinical role for simultaneous whole body PET-MRI in evaluating pediatric cancer patients. 展开更多
关键词 positron emission tomography RADIOLOGY Pediatric imagING ONCOLOGY Cancer Magnetic resonance imagING
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Determination of Fragmentation Schemes and Metabolites of Fluorinated Histone Deacetylase Inhibitors for Use as Positron Emission Tomography Imaging Agents Using HPLC-MS/MS
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作者 Wei-Hsi Chen Yu-Chieh Hsiao +5 位作者 Ming-Hsin Li Mu-Chen Tsai Chun-Fang Feng Han-Chih Chang Hung-Wen Yu Chyng-Yann Shiue 《International Journal of Analytical Mass Spectrometry and Chromatography》 2018年第1期1-19,共19页
High performance liquid chromatography coupled with tandem mass spectrometry was developed and validated as a method for the analysis of fluorinated histone deacetylase inhibitors (F-HDACi), and then employed to study... High performance liquid chromatography coupled with tandem mass spectrometry was developed and validated as a method for the analysis of fluorinated histone deacetylase inhibitors (F-HDACi), and then employed to study their metabolism in biosystems. Four HDACi analogs labeled with the positron emission nuclide 18F constitute a group of potential positron emission tomography imaging agents, which were developed by the Institute of Nuclear Energy Research (INER) and coded as INER-1577 #1, #2, #3, and #4 during animal studies for the diagnosis of dementia. The performance of the method was found to be suitable for the determination of analog #3, and it was employed to determine the structures and fragmentation mechanisms of all four analogs and to study the biotransformations of analogs #3 and #4. The results indicated that the method used for the determination of analog #3 was suitable for determining the abundance of the analogs in chemical and biochemical tests with high precision, accuracy, reproducibility, and recovery. Weaknesses in the chemical bonding of the analogs were found to involve the fluoro, dimethylamino, and benzamide groups in a fragmentation mechanism deduced via tandem mass spectrometry. The metabolites of analogs #3 and #4 in rat liver microsomes and rat plasma were also identified to clarify their characteristic behaviors in biosystems. The major product of analogs #3 in liver microsomes was produced by hydroxylation of the benzylic carbon atom, but in rat plasma the metabolites of analog #3 were produced by hydrolysis of the benzamide group to give a diaminobiphenyl compound with the simultaneous replacement of a fluorine atom by a hydroxyl group. The metabolites of analog #4 in liver microsomes were produced by hydroxylation of the benzylic carbon atom and hydrolysis of the benzamide bond. The results of the studies characterized the chemical and biochemical behaviors of the series F-HADCi analogs. 展开更多
关键词 HISTONE DEACETYLASE Inhibitors positron emission tomography imaging Agent Dementia LC-Tandem MS FRAGMENTATION Mechanism Metabolism Pathways EPIGENETICS
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Positron Emission Tomography-Computed Tomography (PET-CT) in Head and Neck Pathology
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作者 Luis A. Tamara Ines Velez Claudia Tamara 《Open Journal of Radiology》 2011年第1期9-16,共8页
Cancer of the head and neck is often devastating and the morbidity associated with its treatment is substantial. Positron Emission Tomography-Computed Tomography (PET-CT) combines the power of biological / molecular i... Cancer of the head and neck is often devastating and the morbidity associated with its treatment is substantial. Positron Emission Tomography-Computed Tomography (PET-CT) combines the power of biological / molecular imaging with the anatomic detail of CT in order to provide a very sensitive and specific imaging tool for the evaluation of head and neck pathology. PET can aid the clinician in establishing diagnosis, staging, (It has been shown to be more accurate than CT), assessing, prognosis and determining response to therapy. Lymphoma, melanoma, multiple myeloma, leukemia, salivary gland tumors, odontogenic carcinomas, soft tissue sarcomas, thyroid, parathyroid, lacrimal gland and bone / cartilage tumors are some of the entities where PET-CT may be useful. (Tumors of salivary glands and of odontogenic tissue are particularly difficult to diagnose due to the relative infrequency when compared with other tumors and the extremely vast histologic variation).It is important to note that carcinoma metastasis, is the most common malignancy found within the mandibular bone. PET-CT and skeletal scintigraphy are both very sensitive and specific in these types of patients. 展开更多
关键词 pet CT positron emission tomography Head and NECK Cancer.
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New frontiers in focal therapy for prostate cancer:Prostate-specific membrane antigen positron emission tomography/magnetic resonance imaging
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作者 Celeste Manfredi Esau Fernandez-Pascual +2 位作者 Estefanía Linares-Espinós Felipe Couñago Juan Ignacio Martínez-Salamanca 《World Journal of Clinical Oncology》 CAS 2021年第2期61-68,共8页
Imaging has a central role in the context of focal therapy(FT)for prostate cancer(PCa).Prostate-specific membrane antigen(PSMA)positron emission tomography/magnetic resonance imaging(PET/MRI)is a novel imaging modalit... Imaging has a central role in the context of focal therapy(FT)for prostate cancer(PCa).Prostate-specific membrane antigen(PSMA)positron emission tomography/magnetic resonance imaging(PET/MRI)is a novel imaging modality that combines the morpho-functional information of MRI with the molecular characterization of PET.Some papers reported the potential advantages of PSMA PET/MRI in different clinical scenarios.Limited evidence on PSMA PET/MRI is available in the setting of FT.PSMA PET/MRI can be an effective imaging modality for detecting primary PCa and seems to provide accurate local staging of primary PCa.PSMA PET/MRI also shows high performance for restaging and detecting tumor recurrence.The higher soft-tissue contrast and the reduction of ionizing radiation are the main advantages reported in the literature compared to PET/computed tomography.PSMA PET/MRI could represent a turning point in the management of patients with PCa in the context of FT.Further studies are needed to confirm its applications in this specific clinical setting. 展开更多
关键词 Prostate-specific membrane antigen positron emission tomography/magnetic resonance imaging Prostate cancer Focal therapy High-intensity focused ultrasound CRYOTHERAPY
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Accelerating SAGE algorithm in PET image reconstruction by rescaled block-iterative method 被引量:1
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作者 朱宏擎 舒华忠 +1 位作者 周健 罗立民 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期207-210,共4页
A new method to accelerate the convergent rate of the space-alternatinggeneralized expectation-maximization (SAGE) algorithm is proposed. The new rescaled block-iterativeSAGE (RBI-SAGE) algorithm combines the RBI algo... A new method to accelerate the convergent rate of the space-alternatinggeneralized expectation-maximization (SAGE) algorithm is proposed. The new rescaled block-iterativeSAGE (RBI-SAGE) algorithm combines the RBI algorithm with the SAGE algorithm for PET imagereconstruction. In the new approach, the projection data is partitioned into disjoint blocks; eachiteration step involves only one of these blocks. SAGE updates the parameters sequentially in eachblock. In experiments, the RBI-SAGE algorithm and classical SAGE algorithm are compared in theapplication on positron emission tomography (PET) image reconstruction. Simulation results show thatRBI-SAGE has better performance than SAGE in both convergence and image quality. 展开更多
关键词 positron emission tomography space-alternating generalizedexpectation-maximization image reconstruction rescaled block-iterative maximum likelihood
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Row-action SAGE algorithm for PET image reconstruction
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作者 周健 罗立民 朱宏擎 《Journal of Southeast University(English Edition)》 EI CAS 2004年第4期467-471,共5页
The one-block version of ordered subsets (OS) techniques was used to accelerate the convergent rate of the space-alternating generalized expectation-maximization (SAGE) algorithm. The new row-action SAGE (RA-SAGE) alg... The one-block version of ordered subsets (OS) techniques was used to accelerate the convergent rate of the space-alternating generalized expectation-maximization (SAGE) algorithm. The new row-action SAGE (RA-SAGE) algorithm processed projections in sequentially orthogonal order which reduced the dependency among the projections and speeds up the convergences. Additionally, the over-relaxation parameter in the direction defined by the RA-SAGE algorithm was also applied to obtain fast convergence to a globally maximum likelihood (ML) solution. In experiments, the RA-SAGE algorithm and the classical SAGE algorithm were compared in the application to positron emission tomography (PET) image reconstruction. Simulation results showed that RA-SAGE had better performance than SAGE in both convergence and image quality. 展开更多
关键词 image quality Maximum likelihood estimation positron emission tomography Signal to noise ratio
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Primary imaging features and recent application of PET tracers in cerebral amyloid angiopathy
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作者 Wei Zheng Chongchong Gao Zehui Wu 《Journal of Translational Neuroscience》 2024年第2期18-31,共14页
Cerebral amyloid angiopathy(CAA)is a small vessel disease of the brain characterized by the progressive deposition of amyloid-β(Aβ)plaques in the walls of cerebral blood vessels.It presents with a subtle course and ... Cerebral amyloid angiopathy(CAA)is a small vessel disease of the brain characterized by the progressive deposition of amyloid-β(Aβ)plaques in the walls of cerebral blood vessels.It presents with a subtle course and sudden onset,and currently,there are no specific therapeutic interventions available.Accurate diagnosis of CAA could enable targeted interventions in the early stages of the disease,potentially mitigating the disease’s effects.Herein,we review the primary imaging biomarkers used in the diagnosis of CAA,including their mechanisms,imaging characteristics,and significance.We also provide an interpretation of the latest version(v2.0)of the Boston criteria,which are commonly used in the clinical diagnosis of CAA.Additionally,this study introduces various positron emission tomography(PET)tracers for CAA and reviews their application values in the diagnosis of CAA. 展开更多
关键词 cerebral amyloid angiopathy imaging biomarkers Boston criteria positron emission tomography early diagnosis
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Factors influencing image quality and lesion detectability of positron emission tomography: a phantom study
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作者 ZHU Zhaohui FU Zhe 《国际内科双语杂志(中英文)》 2006年第12期62-68,共7页
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