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Sample records for fdg small-animal pet

  1. Optimization of a Model Corrected Blood Input Function from Dynamic FDG-PET Images of Small Animal Heart In Vivo.

    PubMed

    Zhong, Min; Kundu, Bijoy K

    2013-10-01

    Quantitative evaluation of dynamic Positron Emission Tomography (PET) of mouse heart in vivo is challenging due to the small size of the heart and limited intrinsic spatial resolution of the PET scanner. Here, we optimized a compartment model which can simultaneously correct for spill over and partial volume effects for both blood pool and the myocardium, compute kinetic rate parameters and generate model corrected blood input function (MCBIF) from ordered subset expectation maximization - maximum a posteriori (OSEM-MAP) cardiac and respiratory gated (18)F-FDG PET images of mouse heart with attenuation correction in vivo, without any invasive blood sampling. Arterial blood samples were collected from a single mouse to indicate the feasibility of the proposed method. In order to establish statistical significance, venous blood samples from n=6 mice were obtained at 2 late time points, when SP contamination from the tissue to the blood is maximum. We observed that correct bounds and initial guesses for the PV and SP coefficients accurately model the wash-in and wash-out dynamics of the tracer from mouse blood. The residual plot indicated an average difference of about 1.7% between the blood samples and MCBIF. The downstream rate of myocardial FDG influx constant, Ki (0.15±0.03 min(-1)), compared well with Ki obtained from arterial blood samples (P=0.716). In conclusion, the proposed methodology is not only quantitative but also reproducible. PMID:24741130

  2. Noninvasive image derived heart input function for CMRglc measurements in small animal slow infusion FDG PET studies.

    PubMed

    Xiong, Guoming; Paul, Cumming; Todica, Andrei; Hacker, Marcus; Bartenstein, Peter; Böning, Guido

    2012-12-01

    Absolute quantitation of the cerebral metabolic rate for glucose (CMRglc) can be obtained in positron emission tomography (PET) studies when serial measurements of the arterial [(18)F]-fluoro-deoxyglucose (FDG) input are available. Since this is not always practical in PET studies of rodents, there has been considerable interest in defining an image-derived input function (IDIF) by placing a volume of interest (VOI) within the left ventricle of the heart. However, spill-in arising from trapping of FDG in the myocardium often leads to progressive contamination of the IDIF, which propagates to underestimation of the magnitude of CMRglc. We therefore developed a novel, non-invasive method for correcting the IDIF without scaling to a blood sample. To this end, we first obtained serial arterial samples and dynamic FDG-PET data of the head and heart in a group of eight anaesthetized rats. We fitted a bi-exponential function to the serial measurements of the IDIF, and then used the linear graphical Gjedde-Patlak method to describe the accumulation in myocardium. We next estimated the magnitude of myocardial spill-in reaching the left ventricle VOI by assuming a Gaussian point-spread function, and corrected the measured IDIF for this estimated spill-in. Finally, we calculated parametric maps of CMRglc using the corrected IDIF, and for the sake of comparison, relative to serial blood sampling from the femoral artery. The uncorrected IDIF resulted in 20% underestimation of the magnitude of CMRglc relative to the gold standard arterial input method. However, there was no bias with the corrected IDIF, which was robust to the variable extent of myocardial tracer uptake, such that there was a very high correlation between individual CMRglc measurements using the corrected IDIF with gold-standard arterial input results. Based on simulation, we furthermore find that electrocardiogram-gating, i.e. ECG-gating is not necessary for IDIF quantitation using our approach. PMID:23160517

  3. Noninvasive image derived heart input function for CMRglc measurements in small animal slow infusion FDG PET studies

    NASA Astrophysics Data System (ADS)

    Xiong, Guoming; Cumming, Paul; Todica, Andrei; Hacker, Marcus; Bartenstein, Peter; Böning, Guido

    2012-12-01

    Absolute quantitation of the cerebral metabolic rate for glucose (CMRglc) can be obtained in positron emission tomography (PET) studies when serial measurements of the arterial [18F]-fluoro-deoxyglucose (FDG) input are available. Since this is not always practical in PET studies of rodents, there has been considerable interest in defining an image-derived input function (IDIF) by placing a volume of interest (VOI) within the left ventricle of the heart. However, spill-in arising from trapping of FDG in the myocardium often leads to progressive contamination of the IDIF, which propagates to underestimation of the magnitude of CMRglc. We therefore developed a novel, non-invasive method for correcting the IDIF without scaling to a blood sample. To this end, we first obtained serial arterial samples and dynamic FDG-PET data of the head and heart in a group of eight anaesthetized rats. We fitted a bi-exponential function to the serial measurements of the IDIF, and then used the linear graphical Gjedde-Patlak method to describe the accumulation in myocardium. We next estimated the magnitude of myocardial spill-in reaching the left ventricle VOI by assuming a Gaussian point-spread function, and corrected the measured IDIF for this estimated spill-in. Finally, we calculated parametric maps of CMRglc using the corrected IDIF, and for the sake of comparison, relative to serial blood sampling from the femoral artery. The uncorrected IDIF resulted in 20% underestimation of the magnitude of CMRglc relative to the gold standard arterial input method. However, there was no bias with the corrected IDIF, which was robust to the variable extent of myocardial tracer uptake, such that there was a very high correlation between individual CMRglc measurements using the corrected IDIF with gold-standard arterial input results. Based on simulation, we furthermore find that electrocardiogram-gating, i.e. ECG-gating is not necessary for IDIF quantitation using our approach.

  4. Autoradiographic and Small-Animal PET Comparisons Between 18F-FMISO, 18F-FDG, 18F-FLT and the Hypoxic Selective 64Cu-ATSM in a Rodent Model of Cancer

    PubMed Central

    Dence, Carmen S.; Ponde, Datta E.; Welch, Michael J.; Lewis, Jason S.

    2008-01-01

    Introduction Cu-ATSM, a hypoxia imaging agent, has been shown to be predictive of response to traditional cancer therapies in patients with a wide range of tumors. It is known that the environment of the tumor results in a myriad of physiological consequences, including hypoxia, alterations in metabolism and proliferation. In an effort to better characterize the relationships between Cu-ATSM and other prominent radiopharmaceuticals, this current study was undertaken to compare the regional distribution of 64Cu-ATSM with 18F-FMISO, 18F-FDG and 18F-FLT in 9L tumors. Methods Taking advantage of the different half-life of 18F (t½ = 110 min) in comparison to 64Cu (t½ = 12.7 h), we undertook a dual tracer autoradiography study in 9L tumors. Four groups were examined: (a) 18F-FMISO, 2 h p.i. and 64Cu-ATSM 10 min p.i. (b) 18F-FMISO, 2 h p.i. and 64Cu-ATSM 24 h p.i. (c) 18F-FDG, 1 h p.i. and 64Cu-ATSM 10 min p.i., and (d) 18F-FLT, 1 h p.i. and 64Cu-ATSM 10 min p.i‥ Small animal PET imaging was performed in 9L tumor-bearing rats with imaging on concurrent days comparing 64Cu-ATSM with 18F-FMISO and 18F-FLT. Results It was shown that the regional distribution of 18F-FMISO and 64Cu-ATSM showed an excellent correlation when the 64Cu-ATSM had been allowed to distribute for either 10 min (R2 = 0.84) or 24 h (R2 = 0.86). The regional comparisons between 64Cu-ATSM (10 min) and 18F-FDG (1 h) resulted in a very poor correlation (R2 = 0.08) between the regional uptake of the two agents. The comparison between 18F-FLT and 64Cu-ATSM showed a strong relationship (R2 = 0.83) between the two tracers. The small-animal PET images for the distribution comparisons between 64Cu-ATSM and 18F-FMISO and 18F-FLT were in agreement with the data generated from the autoradiography studies. Conclusions The data show that it is important to remember that a number of different metabolic situations can exist when considering the relationship between regions of high glucose uptake, proliferation and

  5. A Very High Spatial Resolution Detector for Small Animal PET

    SciTech Connect

    Kanai Shah, M.S.

    2007-03-06

    Positron Emission Tomography (PET) is an in vivo analog of autoradiography and has the potential to become a powerful new tool in imaging biological processes in small laboratory animals. PET imaging of small animals can provide unique information that can help in advancement of human disease models as well as drug development. Clinical PET scanners used for human imaging are bulky, expensive and do not have adequate spatial resolution for small animal studies. Hence, dedicated, low cost instruments are required for conducting small animal studies with higher spatial resolution than what is currently achieved with clinical as well as dedicated small animal PET scanners. The goal of the proposed project is to investigate a new all solid-state detector design for small animal PET imaging. Exceptionally high spatial resolution, good timing resolution, and excellent energy resolution are expected from the proposed detector design. The Phase I project was aimed at demonstrating the feasibility of producing high performance solid-state detectors that provide high sensitivity, spatial resolution, and timing characteristics. Energy resolution characteristics of the new detector were also investigated. The goal of the Phase II project is to advance the promising solid-state detector technology for small animal PET and determine its full potential. Detectors modules will be built and characterized and finally, a bench-top small animal PET system will be assembled and evaluated.

  6. Small-animal PET: what is it, and why do we need it?

    PubMed

    Yao, Rutao; Lecomte, Roger; Crawford, Elpida S

    2012-09-01

    Small-animal PET refers to imaging of animals such as rats and mice using dedicated PET scanners. Small-animal PET has been used extensively in modern biomedical research. It provides a quantitative measure of the 3-dimensional distribution of a radiopharmaceutical administered to a live subject noninvasively. In this article, we will discuss the operational and technical aspects of small-animal PET; make some comparisons between small-animal PET and human PET systems; identify the challenges of, opportunities for, and ultimate limitations in applying small-animal PET; and discuss some representative small-animal PET applications. Education objectives: After reading this article, the technologist will be able to explain the requirements and benefits of small-animal PET in biomedical research, describe the design and general characteristics of a small-animal PET system, list and describe some of the challenges of imaging small animals, and discuss several small-animal PET applications. PMID:22582006

  7. [Housing situation of small animals in Swiss pet shops].

    PubMed

    Schrickel, B; Gebhardt-Henrich, S; Steiger, A

    2008-07-01

    This study investigates the situation regarding housing of small animals in Swiss pet shops. Data of 92 pet shops were collected with a questionnaire. On average 813 fish, 52.5 invertebrates, 32.2 small mammals, 26.9 birds, 8.9 reptiles and 2.7 amphibians were offered for sale per pet shop. Small mammals, birds and reptiles were mainly obtained from Swiss breeders, while fish and amphibians were almost exclusively purchased from foreign providers. The housing systems which were sold differed from those in which the animals were kept in the shop. This may be misleading to the future pet owners and may lead to faulty husbandry. Animals on reserve were often kept in different housing systems than those in the pet shop. Sick animals were usually treated or killed by the pet shop owners. The killing methods varied between the various species. PMID:18714938

  8. Feasibility study of small animal imaging using clinical PET/CT scanner

    NASA Astrophysics Data System (ADS)

    Hsu, Wen-Lin; Chen, Chia-Lin; Wang, Ze-Jing; Wu, Tung-Hsin; Liu, Dai-Wei; Lee, Jason J. S.

    2007-02-01

    The feasibility of small animal imaging using a clinical positron emission tomography/computed tomography (PET/CT) scanner with [F-18]-fluoro-2-deoxy- D-glucose (FDG) was evaluated. Two protocols in PET/CT system, single-mouse high-resolution mode (SHR) and multi-mouse high throughput mode (MHT) protocol were employed to investigate the ability of the scanner and also explored the performance differences between microPET and clinical PET/CT. In this study, we have found that even the clinical PET/CT scanner could not compete with the microPET scanner, especially in spatial resolution; the high-resolution CT image could advance the anatomical information to sub-millimeter level. Besides, CT-based attenuation correction can improve the image uniformity characteristics and quantification accuracy, and the large bore of a human whole-body scanner broadens the possibility of high throughput studies. Considering all the benefits, clinical PET/CT imaging might be a potential alternative for small animal study.

  9. PET Quantification of Cerebral Oxygen Metabolism in Small Animals

    PubMed Central

    Temma, Takashi; Koshino, Kazuhiro; Moriguchi, Tetsuaki; Enmi, Jun-ichiro; Iida, Hidehiro

    2014-01-01

    Understanding cerebral oxygen metabolism is of great importance in both clinical diagnosis and animal experiments because oxygen is a fundamental source of brain energy and supports brain functional activities. Since small animals such as rats are widely used to study various diseases including cerebral ischemia, cerebrovascular diseases, and neurodegenerative diseases, the development of a noninvasive in vivo measurement method of cerebral oxygen metabolic parameters such as oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO2) as well as cerebral blood flow (CBF) and cerebral blood volume (CBV) has been a priority. Although positron emission tomography (PET) with 15O labeled gas tracers has been recognized as a powerful way to evaluate cerebral oxygen metabolism in humans, this method could not be applied to rats due to technical problems and there were no reports of PET measurement of cerebral oxygen metabolism in rats until an 15O-O2 injection method was developed a decade ago. Herein, we introduce an intravenous administration method using two types of injectable 15O-O2 and an 15O-O2 gas inhalation method through an airway placed in the trachea, which enables oxygen metabolism measurements in rats. PMID:25202714

  10. Use of [18F]fluorodeoxyglucose and the ATLAS small animal PET scanner to examine cerebral functional activation by whisker stimulation in unanesthetized rats

    PubMed Central

    Ravasi, Laura; Shimoji, Kazuaki; Soto-Montenegro, Marisa L.; Esaki, Takanori; Seidel, Jurgen; Sokoloff, Louis; Schmidt, Kathleen

    2011-01-01

    Purpose Stroking the whiskers of a rat is known to increase cerebral blood flow and glucose utilization in the somatosensory cortex. We sought to determine if this activation could be detected with small animal PET and [18F]FDG. Methods Awake rats were co-injected with [18F]FDG and [14C]DG, and during uptake of the tracers, either 5, 10, or 15 whiskers on one side of the face were continuously stimulated. At the end of uptake the animal was killed and imaged with the ATLAS small animal PET scanner. 14C autoradiography was then performed on brain sections obtained from each animal, and increases in tracer uptake in the somatosensory cortex were compared to those determined with PET. Results Both methods showed increases in [18F]FDG and [14C]DG uptake in the somatosensory cortex in response to stimulation of as few as five whiskers. However, the magnitude of activation determined from the PET images was less than that from autoradiography due to the lower spatial resolution of the PET scanner. Conclusions ATLAS small animal PET imaging with [18F]FDG can be used to assess neuronal functional activity in vivo. PMID:21326123

  11. Non-Invasive imaging of small-animal tumors: high-frequency ultrasound vs. MicroPET.

    PubMed

    Liao, Ai-Ho; Li, Chen-Han; Cheng, Weng-Fang; Li, Pai-Chi

    2005-01-01

    Tumor volume measurement on small animals is important but currently invasive. We employ ultrasonic micro-imaging (UMI) in this study and demonstrate its feasibility. In addition, we use small animal positron emission tomography (microPET) as a preliminary effort to develop multi-modality small animal imaging techniques. The tumor growth curve from UMI is also compared to radioactivity from microPET. Both UMI and [18F] FDG microPET imaging were performed on C57BL/6J black mice bearing WF-3 ovary cancer cells at various stages from the second week till up to the eighth week. Segmentation and 3D reconstruction were also done. The growth curve was obtained in vivo noninvasively by UMI. The cell doubling time was 7.46 days according to UMI. This result was compared with vernier caliper measurement and radioactivity counting by microPET. In microPET, we obtained the time-activity curves from the tumor and the tumor-surrounding tissue. The tumor-to-normal-tissues ratios reached maximum at the fifth week after tumor cell implantation. PMID:17281549

  12. Development of a PET Scanner for Simultaneously Imaging Small Animals with MRI and PET

    PubMed Central

    Thompson, Christopher J; Goertzen, Andrew L; Thiessen, Jonathan D; Bishop, Daryl; Stortz, Greg; Kozlowski, Piotr; Retière, Fabrice; Zhang, Xuezhu; Sossi, Vesna

    2014-01-01

    Recently, positron emission tomography (PET) is playing an increasingly important role in the diagnosis and staging of cancer. Combined PET and X-ray computed tomography (PET-CT) scanners are now the modality of choice in cancer treatment planning. More recently, the combination of PET and magnetic resonance imaging (MRI) is being explored in many sites. Combining PET and MRI has presented many challenges since the photo-multiplier tubes (PMT) in PET do not function in high magnetic fields, and conventional PET detectors distort MRI images. Solid state light sensors like avalanche photo-diodes (APDs) and more recently silicon photo-multipliers (SiPMs) are much less sensitive to magnetic fields thus easing the compatibility issues. This paper presents the results of a group of Canadian scientists who are developing a PET detector ring which fits inside a high field small animal MRI scanner with the goal of providing simultaneous PET and MRI images of small rodents used in pre-clinical medical research. We discuss the evolution of both the crystal blocks (which detect annihilation photons from positron decay) and the SiPM array performance in the last four years which together combine to deliver significant system performance in terms of speed, energy and timing resolution. PMID:25120157

  13. Development of a PET scanner for simultaneously imaging small animals with MRI and PET.

    PubMed

    Thompson, Christopher J; Goertzen, Andrew L; Thiessen, Jonathan D; Bishop, Daryl; Stortz, Greg; Kozlowski, Piotr; Retière, Fabrice; Zhang, Xuezhu; Sossi, Vesna

    2014-01-01

    Recently, positron emission tomography (PET) is playing an increasingly important role in the diagnosis and staging of cancer. Combined PET and X-ray computed tomography (PET-CT) scanners are now the modality of choice in cancer treatment planning. More recently, the combination of PET and magnetic resonance imaging (MRI) is being explored in many sites. Combining PET and MRI has presented many challenges since the photo-multiplier tubes (PMT) in PET do not function in high magnetic fields, and conventional PET detectors distort MRI images. Solid state light sensors like avalanche photo-diodes (APDs) and more recently silicon photo-multipliers (SiPMs) are much less sensitive to magnetic fields thus easing the compatibility issues. This paper presents the results of a group of Canadian scientists who are developing a PET detector ring which fits inside a high field small animal MRI scanner with the goal of providing simultaneous PET and MRI images of small rodents used in pre-clinical medical research. We discuss the evolution of both the crystal blocks (which detect annihilation photons from positron decay) and the SiPM array performance in the last four years which together combine to deliver significant system performance in terms of speed, energy and timing resolution. PMID:25120157

  14. Innovations in Small-Animal PET/MR Imaging Instrumentation.

    PubMed

    Tsoumpas, Charalampos; Visvikis, Dimitris; Loudos, George

    2016-04-01

    Multimodal imaging has led to a more detailed exploration of different physiologic processes with integrated PET/MR imaging being the most recent entry. Although the clinical need is still questioned, it is well recognized that it represents one of the most active and promising fields of medical imaging research in terms of software and hardware. The hardware developments have moved from small detector components to high-performance PET inserts and new concepts in full systems. Conversely, the software focuses on the efficient performance of necessary corrections without the use of CT data. The most recent developments in both directions are reviewed. PMID:26952725

  15. FDG-PET imaging in hematological malignancies.

    PubMed

    Valls, L; Badve, C; Avril, S; Herrmann, K; Faulhaber, P; O'Donnell, J; Avril, N

    2016-07-01

    The majority of aggressive lymphomas is characterized by an up regulated glycolytic activity, which enables the visualization by F-18 FDG-PET/CT. One-stop hybrid FDG-PET/CT combines the functional and morphologic information, outperforming both, CT and FDG-PET as separate imaging modalities. This has resulted in several recommendations using FDG-PET/CT for staging, restaging, monitoring during therapy, and assessment of treatment response as well as identification of malignant transformation. FDG-PET/CT may obviate the need for a bone marrow biopsy in patients with Hodgkin's lymphoma and diffuse large B cell lymphoma. FDG-PET/CT response assessment is recommended for FDG-avid lymphomas, whereas CT-based response evaluation remains important in lymphomas with low or variable FDG avidity. The treatment induced change in metabolic activity allows for assessment of response after completion of therapy as well as prediction of outcome early during therapy. The five-point scale Deauville Criteria allows the assessment of treatment response based on visual FDG-PET analysis. Although the use of FDG-PET/CT for prediction of therapeutic response is promising it should only be conducted in the context of clinical trials. Surveillance FDG-PET/CT after complete remission is discouraged due to the relative high number of false-positive findings, which in turn may result in further unnecessary investigations. Future directions include the use of new PET tracers such as F-18 fluorothymidine (FLT), a surrogate biomarker of cellular proliferation and Ga-68 CXCR4, a chemokine receptor imaging biomarker as well as innovative digital PET/CT and PET/MRI techniques. PMID:27090170

  16. Neuroimaging in Animal Seizure Models with 18FDG-PET

    PubMed Central

    Mirrione, Martine M.; Tsirka, Stella E.

    2011-01-01

    Small animal neuroimaging has become increasingly available to researchers, expanding the breadth of questions studied with these methods. Applying these noninvasive techniques to the open questions underlying epileptogenesis is no exception. A major advantage of small animal neuroimaging is its translational appeal. Studies can be well controlled and manipulated, examining the living brain in the animal before, during, and after the disease onset or disease treatment. The results can also be compared to data collected on human patients. Over the past decade, we and others have explored metabolic patterns in animal models of epilepsy to gain insight into the circuitry underlying development of the disease. In this paper, we provide technical details on how metabolic imaging that uses 2-deoxy-2[18F]fluoro-D-glucose (18FDG) and positron emission tomography (PET) is performed and explain the strengths and limitations of these studies. We will also highlight recent advances toward understanding epileptogenesis through small animal imaging. PMID:22937232

  17. FDG PET/CT of Intercostal Schwannoma.

    PubMed

    Wang, Si-Yun; Luo, Dong-Lan; Chen, Gang; Liu, En-Tao; Wang, Shu-Xia

    2016-06-01

    Intercostal schwannoma is rare. We report FDG PET/CT findings of intercostal schwannoma in a 66-year-old woman. The tumor contains both solid and cystic components with intense FDG activity in the solid component. Postsurgical pathology diagnosis revealed schwannoma. PMID:26859215

  18. Full 3-D cluster-based iterative image reconstruction tool for a small animal PET camera

    NASA Astrophysics Data System (ADS)

    Valastyán, I.; Imrek, J.; Molnár, J.; Novák, D.; Balkay, L.; Emri, M.; Trón, L.; Bükki, T.; Kerek, A.

    2007-02-01

    Iterative reconstruction methods are commonly used to obtain images with high resolution and good signal-to-noise ratio in nuclear imaging. The aim of this work was to develop a scalable, fast, cluster based, fully 3-D iterative image reconstruction package for our small animal PET camera, the miniPET. The reconstruction package is developed to determine the 3-D radioactivity distribution from list mode type of data sets and it can also simulate noise-free projections of digital phantoms. We separated the system matrix generation and the fully 3-D iterative reconstruction process. As the detector geometry is fixed for a given camera, the system matrix describing this geometry is calculated only once and used for every image reconstruction, making the process much faster. The Poisson and the random noise sensitivity of the ML-EM iterative algorithm were studied for our small animal PET system with the help of the simulation and reconstruction tool. The reconstruction tool has also been tested with data collected by the miniPET from a line and a cylinder shaped phantom and also a rat.

  19. Efficient system modeling for a small animal PET scanner with tapered DOI detectors

    NASA Astrophysics Data System (ADS)

    Zhang, Mengxi; Zhou, Jian; Yang, Yongfeng; Rodríguez-Villafuerte, Mercedes; Qi, Jinyi

    2016-01-01

    A prototype small animal positron emission tomography (PET) scanner for mouse brain imaging has been developed at UC Davis. The new scanner uses tapered detector arrays with depth of interaction (DOI) measurement. In this paper, we present an efficient system model for the tapered PET scanner using matrix factorization and a virtual scanner geometry. The factored system matrix mainly consists of two components: a sinogram blurring matrix and a geometrical matrix. The geometric matrix is based on a virtual scanner geometry. The sinogram blurring matrix is estimated by matrix factorization. We investigate the performance of different virtual scanner geometries. Both simulation study and real data experiments are performed in the fully 3D mode to study the image quality under different system models. The results indicate that the proposed matrix factorization can maintain image quality while substantially reduce the image reconstruction time and system matrix storage cost. The proposed method can be also applied to other PET scanners with DOI measurement.

  20. A small animal PET based on GAPDs and charge signal transmission approach for hybrid PET-MR imaging

    NASA Astrophysics Data System (ADS)

    Kang, Jihoon; Choi, Yong; Hong, Key Jo; Hu, Wei; Jung, Jin Ho; Huh, Yoonsuk; Kim, Byung-Tae

    2011-08-01

    Positron emission tomography (PET) employing Geiger-mode avalanche photodiodes (GAPDs) and charge signal transmission approach was developed for small animal imaging. Animal PET contained 16 LYSO and GAPD detector modules that were arranged in a 70 mm diameter ring with an axial field of view of 13 mm. The GAPDs charge output signals were transmitted to a preamplifier located remotely using 300 cm flexible flat cables. The position decoder circuits (PDCs) were used to multiplex the PET signals from 256 to 4 channels. The outputs of the PDCs were digitized and further-processed in the data acquisition unit. The cross-compatibilities of the PET detectors and MRI were assessed outside and inside the MRI. Experimental studies of the developed full ring PET were performed to examine the spatial resolution and sensitivity. Phantom and mouse images were acquired to examine the imaging performance. The mean energy and time resolution of the PET detector were 17.6% and 1.5 ns, respectively. No obvious degradation on PET and MRI was observed during simultaneous PET-MRI data acquisition. The measured spatial resolution and sensitivity at the CFOV were 2.8 mm and 0.7%, respectively. In addition, a 3 mm diameter line source was clearly resolved in the hot-sphere phantom images. The reconstructed transaxial PET images of the mouse brain and tumor displaying the glucose metabolism patterns were imaged well. These results demonstrate GAPD and the charge signal transmission approach can allow the development of high performance small animal PET with improved MR compatibility.

  1. Raytest ClearPET™, a new generation small animal PET scanner

    NASA Astrophysics Data System (ADS)

    Sempere Roldan, P.; Chereul, E.; Dietzel, O.; Magnier, L.; Pautrot, C.; Rbah, L.; Sappey-Marinier, D.; Wagner, A.; Zimmer, L.; Janier, M.; Tarazona, V.; Dietzel, G.

    2007-02-01

    The ClearPET is a high-performance small animal PET scanner that has been developed by the Crystal Clear Collaboration (CCC) and is now commercially available to customers worldwide through the Raytest group. Its high sensitivity and spatial resolution are achieved, thanks to a patented phoswich configuration made of two types of scintillating crystals: L(Y)SO and LuYAP:Ce, thus providing depth of interaction information. The ClearPET presents a modular design and it allows for 360° rotation of the detector modules around the field of view (FOV). The ClearPET also presents the unique feature of having an adjustable FOV diameter, thus being suitable for small and medium size animal PET studies. This paper shows the performances of the commercial ClearPET in terms of its spatial resolution, sensitivity and quality of phantoms and preclinical images obtained. It also describes the updated situation of the first commercial unit sold to the Animage platform in Lyon.

  2. A rat head holder for simultaneous scanning of two rats in small animal PET scanners: Design, construction, feasibility testing and kinetic validation

    PubMed Central

    Cheng, Tee Ean; Yoder, Karmen K.; Normandin, Marc D.; Risacher, Shannon L.; Converse, Alexander K.; Hampel, Joseph A.; Miller, Michael A.; Morris, Evan D.

    2013-01-01

    To reduce imaging costs, we designed a head holder for scanning two rats simultaneously in small animal PET scanners. Our goals were (i) to maintain high sensitivity and (ii) to minimize repositioning error between scans. Methods A semi-stereotaxic dual rat head holder was designed and constructed for dual rat scanning in our IndyPET-II scanner and the commercial microPET P4. It was also used for single rat scanning in a small-bore, high-resolution animal scanner (“ISAP”). Positional repeatability was validated via multiple [11C]Raclopride scans of a single rat on different days. Accuracy of repositioning was determined by visual comparison of images, and by metrics derived through image alignment. Kinetic validation was assessed via analysis of [18F]Fluorodeoxyglucose ([18F]FDG) dynamic PET studies of six rats. Each rat was scanned twice: once individually, with brain positioned at the center of field of view (CFOV), and once with a partner, with brain away from CFOV. Both rats were injected with FDG during each dual rat session. Patlak uptake constants (Ki) were calculated from whole brain images. Effects of attenuation and scatter correction on single versus dual scan images were explored. Results Image comparison and alignment metrics indicated excellent repositioning of rats. Scaled time-activity-curves from single and dual rat scans were indistinguishable. Average single and dual scan Ki values differed by only 6.3 ± 7.5%. Conclusion Dual rat scanning in a semi-sterotaxic holder is practical for economical small animal scanning and does not compromise kinetic accuracy of [18F]FDG dynamic scan data. PMID:18824025

  3. Practical method for radioactivity distribution analysis in small-animal PET cancer studies

    PubMed Central

    Slavine, Nikolai V.; Antich, Peter P.

    2008-01-01

    We present a practical method for radioactivity distribution analysis in small-animal tumors and organs using positron emission tomography imaging with a calibrated source of known activity and size in the field of view. We reconstruct the imaged mouse together with a source under the same conditions, using an iterative method, Maximum Likelihood Expectation-Maximization with System Modeling, capable of delivering high resolution images. Corrections for the ratios of geometrical efficiencies, radioisotope decay in time and photon attenuation are included in the algorithm. We demonstrate reconstruction results for the amount of radioactivity within the scanned mouse in a sample study of osteolytic and osteoblastic bone metastasis from prostate cancer xenografts. Data acquisition was performed on the small-animal PET system which was tested with different radioactive sources, phantoms and animals to achieve high sensitivity and spatial resolution. Our method uses high resolution images to determine the volume of organ or tumor and the amount of their radioactivity, has the possibility of saving time, effort and the necessity to sacrifice animals. This method has utility for prognosis and quantitative analysis in small-animal cancer studies, and will enhance the assessment of characteristics of tumor growth, identifying metastases, and potentially determining the effectiveness of cancer treatment. The possible application for this technique could be useful for the organ radioactivity dosimetry studies. PMID:18667322

  4. A method for small-animal PET/CT alignment calibration

    NASA Astrophysics Data System (ADS)

    Pascau, J.; Vaquero, J. J.; Chamorro-Servent, J.; Rodríguez-Ruano, A.; Desco, M.

    2012-06-01

    Small-animal positron-emission tomography/computed tomography (PET/CT) scanners provide anatomical and molecular imaging, which enables the joint visualization and analysis of both types of data. A proper alignment calibration procedure is essential for small-animal imaging since resolution is much higher than that in human devices. This work presents an alignment phantom and two different calibration methods that provide a reliable and repeatable measurement of the spatial geometrical alignment between the PET and the CT subsystems of a hybrid scanner. The phantom can be built using laboratory materials, and it is meant to estimate the rigid spatial transformation that aligns both modalities. It consists of three glass capillaries filled with a positron-emitter solution and positioned in a non-coplanar triangular geometry inside the system field of view. The calibration methods proposed are both based on automatic line detection, but with different approaches to calculate the transformation of the lines between both modalities. Our results show an average accuracy of the alignment estimation of 0.39 mm over the whole field of view.

  5. Noise reduction in small-animal PET images using a multiresolution transform.

    PubMed

    Mejia, Jose M; Ochoa Domínguez, Humberto de Jesús; Vergara Villegas, Osslan Osiris; Ortega Máynez, Leticia; Mederos, Boris

    2014-10-01

    In this paper, we address the problem of denoising reconstructed small animal positron emission tomography (PET) images, based on a multiresolution approach which can be implemented with any transform such as contourlet, shearlet, curvelet, and wavelet. The PET images are analyzed and processed in the transform domain by modeling each subband as a set of different regions separated by boundaries. Homogeneous and heterogeneous regions are considered. Each region is independently processed using different filters: a linear estimator for homogeneous regions and a surface polynomial estimator for the heterogeneous region. The boundaries between the different regions are estimated using a modified edge focusing filter. The proposed approach was validated by a series of experiments. Our method achieved an overall reduction of up to 26% in the %STD of the reconstructed image of a small animal NEMA phantom. Additionally, a test on a simulated lesion showed that our method yields better contrast preservation than other state-of-the art techniques used for noise reduction. Thus, the proposed method provides a significant reduction of noise while at the same time preserving contrast and important structures such as lesions. PMID:24951682

  6. Correction of MRI-induced geometric distortions in whole-body small animal PET-MRI

    SciTech Connect

    Frohwein, Lynn J. Schäfers, Klaus P.; Hoerr, Verena; Faber, Cornelius

    2015-07-15

    Purpose: The fusion of positron emission tomography (PET) and magnetic resonance imaging (MRI) data can be a challenging task in whole-body PET-MRI. The quality of the registration between these two modalities in large field-of-views (FOV) is often degraded by geometric distortions of the MRI data. The distortions at the edges of large FOVs mainly originate from MRI gradient nonlinearities. This work describes a method to measure and correct for these kind of geometric distortions in small animal MRI scanners to improve the registration accuracy of PET and MRI data. Methods: The authors have developed a geometric phantom which allows the measurement of geometric distortions in all spatial axes via control points. These control points are detected semiautomatically in both PET and MRI data with a subpixel accuracy. The spatial transformation between PET and MRI data is determined with these control points via 3D thin-plate splines (3D TPS). The transformation derived from the 3D TPS is finally applied to real MRI mouse data, which were acquired with the same scan parameters used in the phantom data acquisitions. Additionally, the influence of the phantom material on the homogeneity of the magnetic field is determined via field mapping. Results: The spatial shift according to the magnetic field homogeneity caused by the phantom material was determined to a mean of 0.1 mm. The results of the correction show that distortion with a maximum error of 4 mm could be reduced to less than 1 mm with the proposed correction method. Furthermore, the control point-based registration of PET and MRI data showed improved congruence after correction. Conclusions: The developed phantom has been shown to have no considerable negative effect on the homogeneity of the magnetic field. The proposed method yields an appropriate correction of the measured MRI distortion and is able to improve the PET and MRI registration. Furthermore, the method is applicable to whole-body small animal

  7. Evaluation of Matrix9 silicon photomultiplier array for small-animal PET

    PubMed Central

    Du, Junwei; Schmall, Jeffrey P.; Yang, Yongfeng; Di, Kun; Roncali, Emilie; Mitchell, Gregory S.; Buckley, Steve; Jackson, Carl; Cherry, Simon R.

    2015-01-01

    Purpose: The MatrixSL-9-30035-OEM (Matrix9) from SensL is a large-area silicon photomultiplier (SiPM) photodetector module consisting of a 3 × 3 array of 4 × 4 element SiPM arrays (total of 144 SiPM pixels) and incorporates SensL’s front-end electronics board and coincidence board. Each SiPM pixel measures 3.16 × 3.16 mm2 and the total size of the detector head is 47.8 × 46.3 mm2. Using 8 × 8 polished LSO/LYSO arrays (pitch 1.5 mm) the performance of this detector system (SiPM array and readout electronics) was evaluated with a view for its eventual use in small-animal positron emission tomography (PET). Methods: Measurements of noise, signal, signal-to-noise ratio, energy resolution, flood histogram quality, timing resolution, and array trigger error were obtained at different bias voltages (28.0–32.5 V in 0.5 V intervals) and at different temperatures (5 °C–25 °C in 5 °C degree steps) to find the optimal operating conditions. Results: The best measured signal-to-noise ratio and flood histogram quality for 511 keV gamma photons were obtained at a bias voltage of 30.0 V and a temperature of 5 °C. The energy resolution and timing resolution under these conditions were 14.2% ± 0.1% and 4.2 ± 0.1 ns, respectively. The flood histograms show that all the crystals in the 1.5 mm pitch LSO array can be clearly identified and that smaller crystal pitches can also be resolved. Flood histogram quality was also calculated using different center of gravity based positioning algorithms. Improved and more robust results were achieved using the local 9 pixels for positioning along with an energy offset calibration. To evaluate the front-end detector readout, and multiplexing efficiency, an array trigger error metric is introduced and measured at different lower energy thresholds. Using a lower energy threshold greater than 150 keV effectively eliminates any mispositioning between SiPM arrays. Conclusions: In summary, the Matrix9 detector system can resolve

  8. First results in the application of silicon photomultiplier matrices to small animal PET

    NASA Astrophysics Data System (ADS)

    Llosá, G.; Belcari, N.; Bisogni, M. G.; Collazuol, G.; Marcatili, S.; Boscardin, M.; Melchiorri, M.; Tarolli, A.; Piemonte, C.; Zorzi, N.; Barrillon, P.; Bondil-Blin, S.; Chaumat, V.; de La Taille, C.; Dinu, N.; Puill, V.; Vagnucci, J.-F.; Del Guerra, A.

    2009-10-01

    A very high resolution small animal PET scanner that employs matrices of silicon photomultipliers as photodetectors is under development at the University of Pisa and INFN Pisa. The first SiPM matrices composed of 16 (4×4)1 mm×1 mm pixel elements on a common substrate have been produced at FBK-irst, and are being evaluated for this application. The MAROC2 ASIC developed at LAL-Orsay has been employed for the readout of the SiPM matrices. The devices have been tested with pixelated and continuous LYSO crystals. The results show the good performance of the matrices and lead to the fabrication of matrices with 64 SiPM elements.

  9. A detector head design for small-animal PET with silicon photomultipliers (SiPM).

    PubMed

    Moehrs, Sascha; Del Guerra, Alberto; Herbert, Deborah J; Mandelkern, Mark A

    2006-03-01

    Small-animal PET systems are now striving for sub-millimetre resolution. Current systems based upon PSPMTs and finely pixellated scintillators can be pushed to higher resolution, but at the expense of other performance parameters and a rapidly escalating cost. Moreover, depth of interaction (DOI) information is usually difficult to assess in such systems, even though this information is highly desirable to reduce the parallax error, which is often the dominant error for such high-resolution systems. In this study we propose a high-resolution detector head for a small-animal PET imaging system with intrinsic DOI information. Instead of a pixellated scintillator, our design is based upon the classic Anger camera principle, i.e. the head is constructed of modular layers each consisting of a continuous slab of scintillator, viewed by a new type of compact silicon photodetector. The photodetector is the recently developed silicon photomultiplier (SiPM) that as well as being very compact has many other attractive properties: high gain at low bias voltage, excellent single-photoelectron resolution and fast timing. A detector head of about 4 x 4 cm2 in area is proposed, constructed from three modular layers of the type described above. We perform a simulation study, using the Monte Carlo simulation package Geant4. The simulation results are used to optimize the geometry of the detector head and characterize its performance. Additionally, hit estimation algorithms are studied to determine the interaction position of annihilation photons correctly over the whole detector surface. The resulting detector has a nearly uniform efficiency for 511 keV photons of approximately 70% and an intrinsic spatial resolution of less than approximately 0.4 mm full width at half maximum (fwhm). PMID:16481681

  10. A detector head design for small-animal PET with silicon photomultipliers (SiPM)

    NASA Astrophysics Data System (ADS)

    Moehrs, Sascha; DelGuerra, Alberto; Herbert, Deborah J.; Mandelkern, Mark A.

    2006-03-01

    Small-animal PET systems are now striving for sub-millimetre resolution. Current systems based upon PSPMTs and finely pixellated scintillators can be pushed to higher resolution, but at the expense of other performance parameters and a rapidly escalating cost. Moreover, depth of interaction (DOI) information is usually difficult to assess in such systems, even though this information is highly desirable to reduce the parallax error, which is often the dominant error for such high-resolution systems. In this study we propose a high-resolution detector head for a small-animal PET imaging system with intrinsic DOI information. Instead of a pixellated scintillator, our design is based upon the classic Anger camera principle, i.e. the head is constructed of modular layers each consisting of a continuous slab of scintillator, viewed by a new type of compact silicon photodetector. The photodetector is the recently developed silicon photomultiplier (SiPM) that as well as being very compact has many other attractive properties: high gain at low bias voltage, excellent single-photoelectron resolution and fast timing. A detector head of about 4 × 4 cm2 in area is proposed, constructed from three modular layers of the type described above. We perform a simulation study, using the Monte Carlo simulation package Geant4. The simulation results are used to optimize the geometry of the detector head and characterize its performance. Additionally, hit estimation algorithms are studied to determine the interaction position of annihilation photons correctly over the whole detector surface. The resulting detector has a nearly uniform efficiency for 511 keV photons of ~70% and an intrinsic spatial resolution of less than ~0.4 mm full width at half maximum (fwhm).

  11. [2D imaging simulations of a small animal PET scanner with DOI measurement: jPET-RD.].

    PubMed

    Yamaya, Taiga; Kitamura, Keishi; Hagiwara, Naoki; Obi, Takashi; Hasegawa, Tomoyuki; Yoshida, Eiji; Tsuda, Tomoaki; Inadama, Naoko; Wada, Yasuhiro; Murayama, Hideo

    2005-01-01

    We present a preliminary study on the design of a high sensitivity small animal DOI-PET scanner: jPET-RD (for Rodents with DOI detectors), which will contribute to molecular imaging. The 4-layer DOI block detector for the jPET-RD that consists of scintillation crystals (1.4 mm x 1.4 mm x 4.5 mm) and a flat panel position-sensitive photomultiplier tube (52 mm x 52 mm) was previously proposed. In this paper, we investigate imaging performance of the jPET-RD through numerical simulations. The scanner has a hexagonal geometry with a small diameter and a large axial aperture. Therefore DOI information is expected to improve resolution uniformity in the whole field of view (FOV). We simulate the scanner for various parameters of the number of DOI channels and the crystal length. Simulated data are reconstructed using the maximum likelihood expectation maximization with accurate system modeling. The trade-off results between background noise and spatial resolution show that only shortening the length of crystal does not improve the trade-off at all, and that 4-layer DOI information improves uniformity of spatial resolution in the whole FOV. Excellent performance of the jPET-RD can be expected based on the numerical simulation results. PMID:15961924

  12. Denoising of high resolution small animal 3D PET data using the non-subsampled Haar wavelet transform

    NASA Astrophysics Data System (ADS)

    Ochoa Domínguez, Humberto de Jesús; Máynez, Leticia O.; Vergara Villegas, Osslan O.; Mederos, Boris; Mejía, José M.; Cruz Sánchez, Vianey G.

    2015-06-01

    PET allows functional imaging of the living tissue. However, one of the most serious technical problems affecting the reconstructed data is the noise, particularly in images of small animals. In this paper, a method for high-resolution small animal 3D PET data is proposed with the aim to reduce the noise and preserve details. The method is based on the estimation of the non-subsampled Haar wavelet coefficients by using a linear estimator. The procedure is applied to the volumetric images, reconstructed without correction factors (plane reconstruction). Results show that the method preserves the structures and drastically reduces the noise that contaminates the image.

  13. FDG PET in Intracranial Carcinomatous Meningitis.

    PubMed

    Heimburger, Céline; Bund, Caroline; Namer, Izzie Jacques

    2016-01-01

    A 63-year-old white man, diagnosed with pT3N2 squamous cell lung carcinoma, underwent right upper lobectomy with adjuvant radiochemotherapy. After a partial epileptic seizure, MRI revealed a solitary right frontal metastasis that was treated with surgical resection followed by stereotaxic radiotherapy. Three months later, the patient presented weight loss, weakness, and headache. He underwent a whole-body FDG PET/CT for restaging. It showed intense FDG uptakes on the brain periphery corresponding to nodular meningeal contrast enhancement on MRI leading to the diagnosis of carcinomatous meningitis, despite negative cerebrospinal fluid cytology. PMID:26447391

  14. Evaluation of Matrix9 silicon photomultiplier array for small-animal PET

    SciTech Connect

    Du, Junwei Schmall, Jeffrey P.; Yang, Yongfeng; Di, Kun; Roncali, Emilie; Mitchell, Gregory S.; Buckley, Steve; Jackson, Carl; Cherry, Simon R.

    2015-02-15

    Purpose: The MatrixSL-9-30035-OEM (Matrix9) from SensL is a large-area silicon photomultiplier (SiPM) photodetector module consisting of a 3 × 3 array of 4 × 4 element SiPM arrays (total of 144 SiPM pixels) and incorporates SensL’s front-end electronics board and coincidence board. Each SiPM pixel measures 3.16 × 3.16 mm{sup 2} and the total size of the detector head is 47.8 × 46.3 mm{sup 2}. Using 8 × 8 polished LSO/LYSO arrays (pitch 1.5 mm) the performance of this detector system (SiPM array and readout electronics) was evaluated with a view for its eventual use in small-animal positron emission tomography (PET). Methods: Measurements of noise, signal, signal-to-noise ratio, energy resolution, flood histogram quality, timing resolution, and array trigger error were obtained at different bias voltages (28.0–32.5 V in 0.5 V intervals) and at different temperatures (5 °C–25 °C in 5 °C degree steps) to find the optimal operating conditions. Results: The best measured signal-to-noise ratio and flood histogram quality for 511 keV gamma photons were obtained at a bias voltage of 30.0 V and a temperature of 5 °C. The energy resolution and timing resolution under these conditions were 14.2% ± 0.1% and 4.2 ± 0.1 ns, respectively. The flood histograms show that all the crystals in the 1.5 mm pitch LSO array can be clearly identified and that smaller crystal pitches can also be resolved. Flood histogram quality was also calculated using different center of gravity based positioning algorithms. Improved and more robust results were achieved using the local 9 pixels for positioning along with an energy offset calibration. To evaluate the front-end detector readout, and multiplexing efficiency, an array trigger error metric is introduced and measured at different lower energy thresholds. Using a lower energy threshold greater than 150 keV effectively eliminates any mispositioning between SiPM arrays. Conclusions: In summary, the Matrix9 detector system

  15. Validation of a small-animal PET simulation using GAMOS: a GEANT4-based framework

    NASA Astrophysics Data System (ADS)

    Cañadas, M.; Arce, P.; Rato Mendes, P.

    2011-01-01

    Monte Carlo-based modelling is a powerful tool to help in the design and optimization of positron emission tomography (PET) systems. The performance of these systems depends on several parameters, such as detector physical characteristics, shielding or electronics, whose effects can be studied on the basis of realistic simulated data. The aim of this paper is to validate a comprehensive study of the Raytest ClearPET small-animal PET scanner using a new Monte Carlo simulation platform which has been developed at CIEMAT (Madrid, Spain), called GAMOS (GEANT4-based Architecture for Medicine-Oriented Simulations). This toolkit, based on the GEANT4 code, was originally designed to cover multiple applications in the field of medical physics from radiotherapy to nuclear medicine, but has since been applied by some of its users in other fields of physics, such as neutron shielding, space physics, high energy physics, etc. Our simulation model includes the relevant characteristics of the ClearPET system, namely, the double layer of scintillator crystals in phoswich configuration, the rotating gantry, the presence of intrinsic radioactivity in the crystals or the storage of single events for an off-line coincidence sorting. Simulated results are contrasted with experimental acquisitions including studies of spatial resolution, sensitivity, scatter fraction and count rates in accordance with the National Electrical Manufacturers Association (NEMA) NU 4-2008 protocol. Spatial resolution results showed a discrepancy between simulated and measured values equal to 8.4% (with a maximum FWHM difference over all measurement directions of 0.5 mm). Sensitivity results differ less than 1% for a 250-750 keV energy window. Simulated and measured count rates agree well within a wide range of activities, including under electronic saturation of the system (the measured peak of total coincidences, for the mouse-sized phantom, was 250.8 kcps reached at 0.95 MBq mL-1 and the simulated peak was

  16. DigiPET: sub-millimeter spatial resolution small-animal PET imaging using thin monolithic scintillators.

    PubMed

    España, Samuel; Marcinkowski, Radoslaw; Keereman, Vincent; Vandenberghe, Stefaan; Van Holen, Roel

    2014-07-01

    A new preclinical PET system based on dSiPMs, called DigiPET, is presented. The system is based on thin monolithic scintillation crystals and exhibits superior spatial resolution at low-cost compared to systems based on pixelated crystals. Current dedicated small-rodent PET scanners have a spatial resolution in the order of 1 mm. Most of them have a large footprint, requiring considerable laboratory space. For rodent brain imaging, a PET scanner with sub-millimeter resolution is desired. To achieve this, crystals with a pixel pitch down to 0.5 mm have been used. However, fine pixels are difficult to produce and will render systems expensive. In this work, we present the first results with a high-resolution preclinical PET scanner based on thin monolithic scintillators and a large solid angle. The design is dedicated to rat-brain imaging and therefore has a very compact geometry. Four detectors were placed in a square arrangement with a distance of 34.5 mm between two opposing detector modules, defining a field of view (FOV) of 32 × 32 × 32 mm(3). Each detector consists of a thin monolithic LYSO crystal of 32 × 32 × 2 mm(3) optically coupled to a digital silicon photomultiplier (dSiPM). Event positioning within each detector was obtained using the maximum likelihood estimation (MLE) method. To evaluate the system performance, we measured the energy resolution, coincidence resolving time (CRT), sensitivity and spatial resolution. The image quality was evaluated by acquiring a hot-rod phantom filled with (18)F-FDG and a rat head one hour after an (18)F-FDG injection. The MLE yielded an average intrinsic spatial resolution on the detector of 0.54 mm FWHM. We obtained a CRT of 680 ps and an energy resolution of 18% FWHM at 511 keV. The sensitivity and spatial resolution obtained at the center of the FOV were 6.0 cps kBq(-1) and 0.7 mm, respectively. In the reconstructed images of the hot-rod phantom, hot rods down to 0.7 mm can be discriminated

  17. In Vivo Biodistribution and Small Animal PET of 64Cu Labeled Antimicrobial Peptoids

    PubMed Central

    Seo, Jiwon; Ren, Gang; Liu, Hongguang; Miao, Zheng; Park, Minyoung; Wang, Yihong; Miller, Tyler M.; Barron, Annelise E.; Cheng, Zhen

    2012-01-01

    Peptoids are a rapidly developing class of biomimetic polymers based on oligo-N-substituted glycine backbones, designed to mimic peptides and proteins. Inspired by natural antimicrobial peptides, a group of cationic amphipathic peptoids has been successfully discovered with a potent and broad-spectrum activity against pathogenic bacteria; however, there are limited studies to address the in vivo pharmacokinetics of the peptoids. Herein, 64Cu labeled DOTA conjugates of three different peptoids and two control peptides were synthesized and assayed in vivo by both biodistribution studies and small animal positron emission tomography (PET). The study was designed in a way to assess how structural differences of the peptidomimetics affect in vivo pharmacokinetics. As amphipathic molecules, major uptake of the peptoids occurred at the liver. Increased kidney uptake was observed by deleting one hydrophobic residue in the peptoid, and 64Cu-3 achieved the highest kidney uptake of all the conjugates tested in this study. In comparison to peptides, our data indicated that peptoids had general in vivo properties of higher tissue accumulation, slower elimination, and higher in vivo stability. Different administration routes (intravenous, intraperitoneal, and oral) were investigated with peptoids. When administered orally, the peptoids showed poor bioavailability, reminiscent to that of peptide. But, remarkably longer passage through the gastrointestinal (GI) tract without rapid digestion was observed for peptoids. These unique in vivo properties of peptoids were rationalized by efficient cellular membrane permeability and protease resistance of peptoids. The results observed in the biodistribution studies could be confirmed by the PET imaging, which provides a reliable way to evaluate in vivo pharmacokinetic properties of peptoids noninvasively and in real time. The pharmacokinetic data presented here can provide an insight for further development of the antimicrobial peptoids

  18. Improved dead-time correction for PET scanners: application to small-animal PET

    NASA Astrophysics Data System (ADS)

    Vicente, E.; Herraiz, J. L.; España, S.; Herranz, E.; Desco, M.; Vaquero, J. J.; Udías, J. M.

    2013-04-01

    Pile-up and dead-time are two main causes of nonlinearity in the response of a PET scanner as a function of activity in the field of view (FOV). For a given scanner and acquisition system, pile-up effects depend on the material and size of the object being imaged and on the distribution of activity inside and outside the FOV, because these factors change the singles-to-coincidences ratio (SCR). Thus, it is difficult to devise an accurate correction that would be valid for any acquisition. In this work, we demonstrate a linear relationship between SCR and effective dead-time, which measures the effects of both dead-time (losses) and pile-up (gains and losses). This relationship allows us to propose a simple method to accurately estimate dead-time and pile-up corrections using only two calibration acquisitions with, respectively, a high and low SCR. The method has been tested with simulations and experimental data for two different scanner geometries: a scanner with large area detectors and no pile-up rejection, and a scanner composed of two full rings of smaller detectors. Our results show that the SCR correction method is accurate within 7%, even for high activities in the FOV, and avoids the bias of the standard single-parameter method.

  19. Design of a Second Generation Firewire Based Data Acquisition System for Small Animal PET Scanners

    PubMed Central

    Lewellen, T.K.; Miyaoka, R.S.; MacDonald, L.R.; Haselman, M.; DeWitt, D.; Hunter, William; Hauck, S.

    2009-01-01

    The University of Washington developed a Firewire based data acquisition system for the MiCES small animal PET scanner. Development work has continued on new imaging scanners that require more data channels and need to be able to operate within a MRI imaging system. To support these scanners, we have designed a new version of our data acquisition system that leverages the capabilities of modern field programmable gate arrays (FPGA). The new design preserves the basic approach of the original system, but puts almost all functions into the FPGA, including the Firewire elements, the embedded processor, and pulse timing and pulse integration. The design has been extended to support implementation of the position estimation and DOl algorithms developed for the cMiCE detector module. The design is centered around an acquisition node board (ANB) that includes 65 ADC channels, Firewire 1394b support, the FPGA, a serial command bus and signal lines to support a rough coincidence window implementation to reject singles events from being sent on the Firewire bus. Adapter boards convert detector signals into differential paired signals to connect to the ANB. PMID:20228958

  20. A LSO β microprobe for measuring input functions for quantitative small animal PET

    NASA Astrophysics Data System (ADS)

    Maramraju, S.; Stoll, S.; Woody, C.; Schlyer, D.; Schiffer, W.; Lee, D.; Dewey, S.; Vaska, P.

    2007-02-01

    A miniature scintillation microprobe has been developed to measure the input function in live rodents for use in longitudinal, quantitative PET studies. The probe consists of a small lutetium oxyorthosilicate (LSO) crystal measuring typically 0.3-0.5 mm diameter ×0.5-2 mm in length that is used to directly detect positrons in the blood or tissue. The probe has a sensitivity of 10-30 Hz/μCi/cm 3 and is primarily sensitive to short-range positrons emitted by labeled radiotracers in the blood. The sensitivity to γ-ray background can be minimized using a variable threshold in the readout to discriminate between positrons and γ's. The probe was implanted in one of the tail veins of a Sprague-Dawley rat and the input function was measured for the injection of 0.8 mCi of FDG in the other tail vein. The probe exhibits a fast time response that is able to quickly and accurately measure the concentration of 18F circulating in the bloodstream. Additional tests were also carried out to study the probe's sensitivity to γ-ray background.

  1. FDG-PET/CT in lymphoma

    PubMed Central

    D'souza, Maria M; Jaimini, Abhinav; Bansal, Abhishek; Tripathi, Madhavi; Sharma, Rajnish; Mondal, Anupam; Tripathi, Rajendra Prashad

    2013-01-01

    Lymphomas are a heterogeneous group of diseases that arise from the constituent cells of the immune system or from their precursors. 18F-fludeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) is now the cornerstone of staging procedures in the state-of-the-art management of Hodgkin's disease and aggressive non-Hodgkin's lymphoma. It plays an important role in staging, restaging, prognostication, planning appropriate treatment strategies, monitoring therapy, and detecting recurrence. However, its role in indolent lymphomas is still unclear and calls for further investigational trials. The protean PET/CT manifestations of lymphoma necessitate a familiarity with the spectrum of imaging findings to enable accurate diagnosis. A meticulous evaluation of PET/CT findings, an understanding of its role in the management of lymphomas, and knowledge of its limitations are mandatory for the optimal utilization of this technique. PMID:24604942

  2. FDG-PET hyperactivity pattern in anti-NMDAr encephalitis.

    PubMed

    Novy, Jan; Allenbach, Gilles; Bien, Christian G; Guedj, Eric; Prior, John O; Rossetti, Andrea O

    2016-08-15

    FDG-PET can show anteroposterior glucose metabolism gradient in anti-NMDAr encephalitis, but there are also suggestions that basal ganglia are involved. We examined FDG-PET scans in 5 consecutive episodes of serologically proven anti-NMDAr encephalitis, compared with healthy controls. We confirmed the anteroposterior metabolic gradient and found a significant FDG uptake increase in the caudate nuclei in episodes of varying intensity and delay from the onset of the symptoms. FDG-PET can be useful in the work-up of suspected anti-NMDAr encephalitis disclosing a characteristic cortical and sub-cortical metabolism pattern. PMID:27397089

  3. Small-Animal PET Imaging of Tau Pathology with 18F-THK5117 in 2 Transgenic Mouse Models.

    PubMed

    Brendel, Matthias; Jaworska, Anna; Probst, Federico; Overhoff, Felix; Korzhova, Viktoria; Lindner, Simon; Carlsen, Janette; Bartenstein, Peter; Harada, Ryuichi; Kudo, Yukitsuka; Haass, Christian; Van Leuven, Fred; Okamura, Nobuyuki; Herms, Jochen; Rominger, Axel

    2016-05-01

    Abnormal accumulation of tau aggregates in the brain is one of the hallmarks of Alzheimer disease neuropathology. We visualized tau deposition in vivo with the previously developed 2-arylquinoline derivative (18)F-THK5117 using small-animal PET in conjunction with autoradiography and immunohistochemistry gold standard assessment in 2 transgenic mouse models expressing hyperphosphorylated tau. Small-animal PET recordings were obtained in groups of P301S (n = 11) and biGT mice (n = 16) of different ages, with age-matched wild-type (WT) serving as controls. After intravenous administration of 16 ± 2 MBq of (18)F-THK5117, a dynamic 90-min emission recording was initiated for P301S mice and during 20-50 min after injection for biGT mice, followed by a 15-min transmission scan. After coregistration to the MRI atlas and scaling to the cerebellum, we performed volume-of-interest-based analysis (SUV ratio [SUVR]) and statistical parametric mapping. Small-animal PET results were compared with autoradiography ex vivo and in vitro and further validated with AT8 staining for neurofibrillary tangles. SUVRs calculated from static recordings during the interval of 20-50 min after tracer injection correlated highly with estimates of binding potential based on the entire dynamic emission recordings (R = 0.85). SUVR increases were detected in the brain stem of aged P301S mice (+11%; P < 0.001) and in entorhinal/amygdaloidal areas (+15%; P < 0.001) of biGT mice when compared with WT, whereas aged WT mice did not show increased tracer uptake. Immunohistochemical tau loads correlated with small-animal PET SUVR for both P301S (R = 0.8; P < 0.001) and biGT (R = 0.7; P < 0.001) mice, and distribution patterns of AT8-positive neurons matched voxelwise statistical parametric mapping analysis. Saturable binding of the tracer was verified by autoradiographic blocking studies. In the first dedicated small-animal PET study in 2 different transgenic tauopathy mouse models using the tau tracer

  4. Small animal simultaneous PET/MRI: initial experiences in a 9.4T microMRI

    SciTech Connect

    Maramraju, S.H.; Schlyer, D.; Maramraju, S.H.; Smith, S.D.; Junnarkar, S.S.; Schulz, D.; Stoll, S.; Ravindranath, B.; Purschke, M.L.; Rescia, S.; Southekal, S.; Pratte, J.-F.; Vaska, P.; Woody, C.L.; Schlyer, D.J.

    2011-03-25

    We developed a non-magnetic positron-emission tomography (PET) device based on the rat conscious animal PET that operates in a small-animal magnetic resonance imaging (MRI) scanner, thereby enabling us to carry out simultaneous PET/MRI studies. The PET detector comprises 12 detector blocks, each being a 4 x 8 array of lutetium oxyorthosilicate crystals (2.22 x 2.22 x 5 mm{sup 3}) coupled to a matching non-magnetic avalanche photodiode array. The detector blocks, housed in a plastic case, form a 38 mm inner diameter ring with an 18 mm axial extent. Custom-built MRI coils fit inside the positron-emission tomography (PET) device, operating in transceiver mode. The PET insert is integrated with a Bruker 9.4 T 210 mm clear-bore diameter MRI scanner. We acquired simultaneous PET/MR images of phantoms, of in vivo rat brain, and of cardiac-gated mouse heart using [{sup 11}C]raclopride and 2-deoxy-2-[{sup 18}F]fluoro-d-glucose PET radiotracers. There was minor interference between the PET electronics and the MRI during simultaneous operation, and small effects on the signal-to-noise ratio in the MR images in the presence of the PET, but no noticeable visual artifacts. Gradient echo and high-duty-cycle spin echo radio frequency (RF) pulses resulted in a 7% and a 28% loss in PET counts, respectively, due to high PET counts during the RF pulses that had to be gated out. The calibration of the activity concentration of PET data during MR pulsing is reproducible within less than 6%. Our initial results demonstrate the feasibility of performing simultaneous PET and MRI studies in adult rats and mice using the same PET insert in a small-bore 9.4 T MRI.

  5. Small animal simultaneous PET/MRI: initial experiences in a 9.4 T microMRI.

    PubMed

    Maramraju, Sri Harsha; Smith, S David; Junnarkar, Sachin S; Schulz, Daniela; Stoll, Sean; Ravindranath, Bosky; Purschke, Martin L; Rescia, Sergio; Southekal, Sudeepti; Pratte, Jean-François; Vaska, Paul; Woody, Craig L; Schlyer, David J

    2011-04-21

    We developed a non-magnetic positron-emission tomography (PET) device based on the rat conscious animal PET that operates in a small-animal magnetic resonance imaging (MRI) scanner, thereby enabling us to carry out simultaneous PET/MRI studies. The PET detector comprises 12 detector blocks, each being a 4 × 8 array of lutetium oxyorthosilicate crystals (2.22 × 2.22 × 5 mm(3)) coupled to a matching non-magnetic avalanche photodiode array. The detector blocks, housed in a plastic case, form a 38 mm inner diameter ring with an 18 mm axial extent. Custom-built MRI coils fit inside the positron-emission tomography (PET) device, operating in transceiver mode. The PET insert is integrated with a Bruker 9.4 T 210 mm clear-bore diameter MRI scanner. We acquired simultaneous PET/MR images of phantoms, of in vivo rat brain, and of cardiac-gated mouse heart using [(11)C]raclopride and 2-deoxy-2-[(18)F]fluoro-D-glucose PET radiotracers. There was minor interference between the PET electronics and the MRI during simultaneous operation, and small effects on the signal-to-noise ratio in the MR images in the presence of the PET, but no noticeable visual artifacts. Gradient echo and high-duty-cycle spin echo radio frequency (RF) pulses resulted in a 7% and a 28% loss in PET counts, respectively, due to high PET counts during the RF pulses that had to be gated out. The calibration of the activity concentration of PET data during MR pulsing is reproducible within less than 6%. Our initial results demonstrate the feasibility of performing simultaneous PET and MRI studies in adult rats and mice using the same PET insert in a small-bore 9.4 T MRI. PMID:21441651

  6. Small animal simultaneous PET/MRI: initial experiences in a 9.4 T microMRI

    NASA Astrophysics Data System (ADS)

    Harsha Maramraju, Sri; Smith, S. David; Junnarkar, Sachin S.; Schulz, Daniela; Stoll, Sean; Ravindranath, Bosky; Purschke, Martin L.; Rescia, Sergio; Southekal, Sudeepti; Pratte, Jean-François; Vaska, Paul; Woody, Craig L.; Schlyer, David J.

    2011-04-01

    We developed a non-magnetic positron-emission tomography (PET) device based on the rat conscious animal PET that operates in a small-animal magnetic resonance imaging (MRI) scanner, thereby enabling us to carry out simultaneous PET/MRI studies. The PET detector comprises 12 detector blocks, each being a 4 × 8 array of lutetium oxyorthosilicate crystals (2.22 × 2.22 × 5 mm3) coupled to a matching non-magnetic avalanche photodiode array. The detector blocks, housed in a plastic case, form a 38 mm inner diameter ring with an 18 mm axial extent. Custom-built MRI coils fit inside the positron-emission tomography (PET) device, operating in transceiver mode. The PET insert is integrated with a Bruker 9.4 T 210 mm clear-bore diameter MRI scanner. We acquired simultaneous PET/MR images of phantoms, of in vivo rat brain, and of cardiac-gated mouse heart using [11C]raclopride and 2-deoxy-2-[18F]fluoro-d-glucose PET radiotracers. There was minor interference between the PET electronics and the MRI during simultaneous operation, and small effects on the signal-to-noise ratio in the MR images in the presence of the PET, but no noticeable visual artifacts. Gradient echo and high-duty-cycle spin echo radio frequency (RF) pulses resulted in a 7% and a 28% loss in PET counts, respectively, due to high PET counts during the RF pulses that had to be gated out. The calibration of the activity concentration of PET data during MR pulsing is reproducible within less than 6%. Our initial results demonstrate the feasibility of performing simultaneous PET and MRI studies in adult rats and mice using the same PET insert in a small-bore 9.4 T MRI.

  7. Quantitative accuracy of MAP reconstruction for dynamic PET imaging in small animals

    PubMed Central

    Cheng, Ju-Chieh (Kevin); Shoghi, Kooresh; Laforest, Richard

    2012-01-01

    Purpose: Iterative reconstruction algorithms are becoming more commonly employed in positron emission tomography (PET) imaging; however, the quantitative accuracy of the reconstructed images still requires validation for various levels of contrast and counting statistics. Methods: The authors present an evaluation of the quantitative accuracy of the 3D maximum a posteriori (3D-MAP) image reconstruction algorithm for dynamic PET imaging with comparisons to two of the most widely used reconstruction algorithms: the 2D filtered-backprojection (2D-FBP) and 2D-ordered subsets expectation maximization (2D-OSEM) on the Siemens microPET scanners. The study was performed for various levels of count density encountered in typical dynamic scanning as well as the imaging of cardiac activity concentration in small animal studies on the Focus 120. Specially designed phantoms were used for evaluation of the spatial resolution, image quality, and quantitative accuracy. A normal mouse was employed to evaluate the accuracy of the blood time activity concentration extracted from left ventricle regions of interest (ROIs) within the images as compared to the actual blood activity concentration measured from arterial blood sampling. Results: For MAP reconstructions, the spatial resolution and contrast have been found to reach a stable value after 20 iterations independent of the β values (i.e., hyper parameter which controls the weight of the penalty term) and count density within the frame. The spatial resolution obtained with 3D-MAP reaches values of ∼1.0 mm with a β of 0.01 while the 2D-FBP has value of 1.8 mm and 2D-OSEM has a value of 1.6 mm. It has been observed that the lower the hyper parameter β used in MAP, more iterations are needed to reach the stable noise level (i.e., image roughness). The spatial resolution is improved by using a lower β value at the expense of higher image noise. However, with similar noise level the spatial resolution achieved by 3D-MAP was

  8. IV Leiomyomatosis on FDG PET/CT.

    PubMed

    Jin, Xiaona; Li, Fang; Lu, Zhaohui; Cheng, Wuying

    2016-07-01

    A 48-year-old woman presented with a 2-month history of right lower extremity edema. Clinical examination only showed right lower limb swelling. Routine laboratory examination revealed no abnormal results. Abdominal ultrasonography identified uterine leiomyoma and soft tissue masses. An abdominal CT demonstrated a continuous mass extending from the right internal and external iliac vein into the common iliac vein and inferior vena cava. To distinguish the mass from malignancy, the patient underwent PET/CT scan which showed increased FDG activity in the mass. However, histopathological examination proved the mass to be IV leiomyomatosis. PMID:26914578

  9. Performance evaluation of a compact PET/SPECT/CT tri-modality system for small animal imaging applications

    NASA Astrophysics Data System (ADS)

    Wei, Qingyang; Wang, Shi; Ma, Tianyu; Wu, Jing; Liu, Hui; Xu, Tianpeng; Xia, Yan; Fan, Peng; Lyu, Zhenlei; Liu, Yaqiang

    2015-06-01

    PET, SPECT and CT imaging techniques are widely used in preclinical small animal imaging applications. In this paper, we present a compact small animal PET/SPECT/CT tri-modality system. A dual-functional, shared detector design is implemented which enables PET and SPECT imaging with a same LYSO ring detector. A multi-pinhole collimator is mounted on the system and inserted into the detector ring in SPECT imaging mode. A cone-beam CT consisting of a micro focus X-ray tube and a CMOS detector is implemented. The detailed design and the performance evaluations are reported in this paper. In PET imaging mode, the measured NEMA based spatial resolution is 2.12 mm (FWHM), and the sensitivity at the central field of view (CFOV) is 3.2%. The FOV size is 50 mm (∅)×100 mm (L). The SPECT has a spatial resolution of 1.32 mm (FWHM) and an average sensitivity of 0.031% at the center axial, and a 30 mm (∅)×90 mm (L) FOV. The CT spatial resolution is 8.32 lp/mm @10%MTF, and the contrast discrimination function value is 2.06% with 1.5 mm size cubic box object. In conclusion, a compact, tri-modality PET/SPECT/CT system was successfully built with low cost and high performance.

  10. Synthesis and quality control of fluorodeoxyglucose and performance assessment of Siemens MicroFocus 220 small animal PET scanner

    NASA Astrophysics Data System (ADS)

    Phaterpekar, Siddhesh Nitin

    The scope of this article is to cover the synthesis and quality control procedures involved in production of Fludeoxyglucose (18F--FDG). The article also describes the cyclotron production of 18F radioisotope and gives a brief overview on operations and working of a fixed energy medical cyclotron. The quality control procedures for FDG involve radiochemical and radionuclidic purity tests, pH tests, chemical purity tests, sterility tests, endotoxin tests. Each of these procedures were carried out for multiple batches of FDG with a passing rate of 95% among 20 batches. The article also covers the quality assurance steps for the Siemens MicroPET Focus 220 Scanner using a Jaszczak phantom. We have carried out spatial resolution tests on the scanner, with an average transaxial resolution of 1.775mm with 2-3mm offset. Tests involved detector efficiency, blank scan sinograms and transmission sinograms. A series of radioactivity distribution tests are also carried out on a uniform phantom, denoting the variations in radioactivity and uniformity by using cylindrical ROIs in the transverse region of the final image. The purpose of these quality control tests is to make sure the manufactured FDG is biocompatible with the human body. Quality assurance tests are carried on PET scanners for efficient performance, and to make sure the quality of images acquired is according to the radioactivity distribution in the subject of interest.

  11. Allergic Reaction to Ginkgo Nut on FDG PET/CT.

    PubMed

    Han, Eun Ji; Park, Hye Lim; Kim, Sung Hoon

    2016-09-01

    We report the case of a 36-year-old woman who previously underwent total thyroidectomy for papillary thyroid carcinoma. F FDG PET/CT images demonstrated multiple lymph nodes with increased FDG uptake in the neck, chest, and abdomen and diffusely increased FDG uptake in the spleen, which were highly suspicious findings for malignant lymphoma. However, subsequent biopsy of axillary lymph node presented reactive hyperplasia. Detailed history revealed that the patient had a history of generalized edema and severe arthralgia after contact with ginkgo nut one week ago. This case highlights allergic reaction mimicking lymphoma on FDG PET/CT. PMID:27276210

  12. Detector development for microPET II: a 1 microl resolution PET scanner for small animal imaging.

    PubMed

    Chatziioannou, A; Tai, Y C; Doshi, N; Cherry, S R

    2001-11-01

    We are currently developing a small animal positron emission tomography (PET) scanner with a design goal of 1 microlitre (1 mm3) image resolution. The detectors consist of a 12 x 12 array of 1 x 1 x 10 mm lutetium oxyorthosilicate (LSO) scintillator crystals coupled to a 64-channel photomultiplier tube (PMT) via 5 cm long optical fibre bundles. The optical fibre connection allows a high detector packing fraction despite the dead space surrounding the active region of the PMT. Optical fibre bundles made from different types of glass were tested for light transmission, and also their effects on crystal identification and energy resolution, and compared to direct coupling of the LSO arrays to the PMTs. We also investigated the effects of extramural absorber (EMA) in the fibre bundles. Based on these results, fibre bundles manufactured from F2 glass were selected. We built three pairs of prototype detectors (directly coupled LSO array, fibre bundle without EMA and fibre bundle with EMA) and measured flood histograms, energy resolution, intrinsic spatial resolution and timing resolution. The results demonstrated an intrinsic spatial resolution (FWHM) of 1.12 mm (directly coupled), 1.23 mm (fibre bundle without EMA coupling) and 1.27 mm (fibre bundle with EMA coupling) using an approximately 500 microm diameter Na-22 point source. Using a 330 microm outer diameter steel needle line source filled with F-18, spatial resolution for the detector with the EMA optical fibre bundle improved to 1.05 mm. The respective timing and energy FWHM values were 1.96 ns, 21% (directly coupled), 2.20 ns, 23% (fibre bundle without EMA) and 2.99 ns, 30% (fibre bundle with EMA). The peak-to-valley ratio in the flood histograms was better with EMA (5:1) compared to the optical fibre bundle without EMA (2.5:1), due to the decreased optical cross-talk. In comparison to the detectors used in our current generation microPET scanner, these detectors substantially improve on the spatial resolution

  13. Predictive and prognostic value of FDG-PET

    PubMed Central

    Oyen, Wim J.G.

    2008-01-01

    Abstract The predictive and prognostic value of fluorodeoxyglucose (FDG)-positron emission tomography (PET) in non-small-cell lung carcinoma, colorectal carcinoma and lymphoma is discussed. The degree of FDG uptake is of prognostic value at initial presentation, after induction treatment prior to resection and in the case of relapse of non-small cell lung cancer (NSCLC). In locally advanced and advanced stages of NSCLC, FDG-PET has been shown to be predictive for clinical outcome at an early stage of treatment. In colorectal carcinoma, limited studies are available on the prognostic value of FDG-PET, however, the technique appears to have great potential in monitoring the success of local ablative therapies soon after intervention and in the prediction and evaluation of response to radiotherapy, systemic therapy, and combinations thereof. The prognostic value of end-of treatment FDG-PET for FDG-avid lymphomas has been established, and the next step is to define how to use this information to optimize patient outcome. In Hodgkin's lymphoma, FDG-PET has a high negative predictive value, however, histological confirmation of positive findings should be sought where possible. For non-Hodgkin's lymphoma, the opposite applies. The newly published standardized guidelines for interpretation formulates specific criteria for visual interpretation and for defining PET positivity in the liver, spleen, lung, bone marrow and small residual lesions. The introduction of these guidelines should reduce variability among studies. Interim PET offers a reliable method for early prediction of long-term remission, however it should only be performed in prospective randomized controlled trials. Many of the diagnostic and management questions considered in this review are relevant to other tumour types. Further research in this field is of great importance, since it may lead to a change in the therapeutic concept of cancer. The preliminary findings call for systematic inclusion of FDG-PET

  14. Preliminary assessment of the imaging capability of the YAP (S)PET small animal scanner in neuroscience

    NASA Astrophysics Data System (ADS)

    Bartoli, Antonietta; Belcari, Nicola; Stark, Daniela; Höhnemann, Sabine; Piel, Markus; Jennewein, Marc; Schmitt, Ulrich; Tillmanns, Julia; Thews, Oliver; Hiemke, Christoph; Roesch, Frank; Del Guerra, Alberto

    2006-12-01

    The new and fully engineered version of the YAP-(S)PET small animal scanner has been tested at the University of Mainz for preliminary assessment of its imaging capability for studies related to neuropharmacology and psychiatry. The main feature of the scanner is the capability to combine PET and SPECT techniques. It allows the development of new and interesting protocols for the investigation of many biological phenomena, more effectively than with PET or SPECT modalities alone. The scanner is made up of four detector heads, each one composed of a 4×4 cm 2 of YAlO 3:Ce (or YAP:Ce) matrix, and has a field of view (FOV) of 4 cm axially×4 cm ∅ transaxially. In PET mode, the volume resolution is less than 8 mm 3 and is nearly constant over the whole FOV, while the sensitivity is about 2%. The SPECT performance is not so good, due to the presence of the multi-hole lead collimator in front of each head. Nevertheless, the YAP-PET scanner offers excellent resolution and sensitivity for performing on the availability of D2-like dopamine receptors on mice and rats in both PET and SPECT modalities.

  15. FDG PET-CT of gynecologic cancers: pearls and pitfalls.

    PubMed

    Prabhakar, Hima B; Kraeft, Jessica J; Schorge, John O; Scott, James A; Lee, Susanna I

    2015-10-01

    FDG PET-CT plays an important role in treatment planning and in prognosis assessment of gynecologic cancer patients. Detection of hypermetabolic tissue with FDG PET, when combined with the high spatial resolution of CT, results in improved cancer detection and localization not afforded by either modality independently. This article is a primer for a radiologist performing PET-CT on gynecologic cancer patients and includes the imaging protocol, normal pattern of FDG distribution in the female pelvis and the lymph node drainage pathways from the gynecologic organs. Clinically relevant imaging findings that should be included in the report are discussed. Case examples illustrate how potential errors in exam interpretation can be avoided by concurrently performing a high-quality diagnostic CT with the FDG PET scan and by analyzing both the stand-alone and the fusion images. PMID:25680500

  16. Preparedness of small animal veterinary practices to communicate with Spanish-speaking pet owners with limited proficiency in English.

    PubMed

    Landau, Ruth E; Beck, Alan; Glickman, Larry T; Litster, Annette; Widmar, Nicole J Olynk; Moore, George E

    2016-03-15

    OBJECTIVE To investigate the preparedness of small animal veterinary personnel to communicate with Spanish-speaking pet owners with limited English-language proficiency (LEP). DESIGN Cross-sectional telephone survey. SAMPLE Data from 383 small animal veterinary practices. PROCEDURES Telephone surveys were conducted with veterinarians and office or practice managers from a random sample of US small animal veterinary practices in 10 states to estimate the number of Spanish-speaking pet owners with LEP visiting these practices, proportion of practices that used services to facilitate communication with Spanish-speaking clients with LEP, and degree of veterinarian satisfaction with their communication with those clients. RESULTS Responses were obtained from 383 of 1,245 (31%) eligible practices, of which 340 (89%) had Spanish-speaking clients with LEP and 200 (52%) had such clients on a weekly basis. Eight percent of practices had veterinary personnel who were conversant or fluent in spoken Spanish. Veterinarians who depended on clients' friends or family to translate were significantly less satisfied with client communication than were those who could converse in Spanish with clients directly. Availability of Spanish-speaking staff and offering of Spanish-language resources were associated with an increase in the number of Spanish-speaking clients with LEP seen on a weekly basis. Industry- and practice-generated Spanish-language materials were offered at 32% (124/383) and 21% (81/383) of practices, respectively; 329 (86%) practices had no Spanish-language marketing. CONCLUSIONS AND CLINICAL RELEVANCE Opportunities were identified for improving communication with pet owners with LEP in the veterinary clinical setting, which could ultimately positively impact patient well-being and client compliance. PMID:26953924

  17. Small Animal Care.

    ERIC Educational Resources Information Center

    Livesey, Dennis W.; Fong, Stephen

    This small animal care course guide is designed for students who will be seeking employment in veterinary hospitals, kennels, grooming shops, pet shops, and small-animal laboratories. The guide begins with an introductory section that gives the educational philosophy of the course, job categories and opportunities, units of instruction required…

  18. A computational pipeline for quantification of pulmonary infections in small animal models using serial PET-CT imaging

    PubMed Central

    2013-01-01

    Background Infectious diseases are the second leading cause of death worldwide. In order to better understand and treat them, an accurate evaluation using multi-modal imaging techniques for anatomical and functional characterizations is needed. For non-invasive imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET), there have been many engineering improvements that have significantly enhanced the resolution and contrast of the images, but there are still insufficient computational algorithms available for researchers to use when accurately quantifying imaging data from anatomical structures and functional biological processes. Since the development of such tools may potentially translate basic research into the clinic, this study focuses on the development of a quantitative and qualitative image analysis platform that provides a computational radiology perspective for pulmonary infections in small animal models. Specifically, we designed (a) a fast and robust automated and semi-automated image analysis platform and a quantification tool that can facilitate accurate diagnostic measurements of pulmonary lesions as well as volumetric measurements of anatomical structures, and incorporated (b) an image registration pipeline to our proposed framework for volumetric comparison of serial scans. This is an important investigational tool for small animal infectious disease models that can help advance researchers’ understanding of infectious diseases. Methods We tested the utility of our proposed methodology by using sequentially acquired CT and PET images of rabbit, ferret, and mouse models with respiratory infections of Mycobacterium tuberculosis (TB), H1N1 flu virus, and an aerosolized respiratory pathogen (necrotic TB) for a total of 92, 44, and 24 scans for the respective studies with half of the scans from CT and the other half from PET. Institutional Administrative Panel on Laboratory Animal

  19. Monte Carlo modelling of singles-mode transmission data for small animal PET scanners

    NASA Astrophysics Data System (ADS)

    Vandervoort, Eric; Camborde, Marie-Laure; Jan, Sébastien; Sossi, Vesna

    2007-06-01

    The attenuation corrections factors (ACFs), which are necessary for quantitatively accurate PET imaging, can be obtained using singles-mode transmission scanning. However, contamination from scatter is a largely unresolved problem for these data. We present an extension of the Monte Carlo simulation tool, GATE, for singles-mode transmission data and its validation using experimental data from the microPET R4 and Focus 120 scanners. We first validated our simulated PET scanner for coincidence-mode data where we found that experimental resolution and scatter fractions (SFs) agreed well for simulations that included positron interactions and scatter in the source material. After modifying GATE to model singles-mode data, we compared simulated and experimental ACFs and SFs for three different sized water cylinders using 57Co (122 keV photon emitter) and 68Ge (positron emitter) transmission sources. We also propose a simple correction for a large background contamination we identified in the 68Ge singles-mode data due to intrinsic 176Lu radioactivity present in the detector crystals. For simulation data, the SFs agreed to within 1.5% and 2.5% of experimental values for background-corrected 68Ge and 57Co transmission data, respectively. This new simulation tool accurately models the photon interactions and data acquisition for singles-mode transmission scans.

  20. Design considerations for a C-shaped PET system, dedicated to small animal brain imaging, using GATE Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Efthimiou, N.; Papadimitroulas, P.; Kostou, T.; Loudos, G.

    2015-09-01

    Commercial clinical and preclinical PET scanners rely on the full cylindrical geometry for whole body scans as well as for dedicated organs. In this study we propose the construction of a low cost dual-head C-shaped PET system dedicated for small animal brain imaging. Monte Carlo simulation studies were performed using GATE toolkit to evaluate the optimum design in terms of sensitivity, distortions in the FOV and spatial resolution. The PET model is based on SiPMs and BGO pixelated arrays. Four different configurations with C- angle 0°, 15°, 30° and 45° within the modules, were considered. Geometrical phantoms were used for the evaluation process. STIR software, extended by an efficient multi-threaded ray tracing technique, was used for the image reconstruction. The algorithm automatically adjusts the size of the FOV according to the shape of the detector's geometry. The results showed improvement in sensitivity of ∼15% in case of 45° C-angle compared to the 0° case. The spatial resolution was found 2 mm for 45° C-angle.

  1. FDG-PET Contributions to the Pathophysiology of Memory Impairment.

    PubMed

    Segobin, Shailendra; La Joie, Renaud; Ritz, Ludivine; Beaunieux, Hélène; Desgranges, Béatrice; Chételat, Gaël; Pitel, Anne Lise; Eustache, Francis

    2015-09-01

    Measurement of synaptic activity by Positron Emission Tomography (PET) and its relation to cognitive functions such as episodic memory, working memory and executive functions in healthy humans and patients with neurocognitive disorders have been well documented. In this review, we introduce the concept of PET imaging that allows the observation of a particular biological process in vivo through the use of radio-labelled compounds, its general use to the medical world and its contributions to the understanding of memory systems. We then focus on [(18)F]-2-fluoro-2-deoxy-D-glucose (FDG-PET), the radiotracer that is used to measure local cerebral metabolic rate of glucose that is indicative of synaptic activity in the brain. FDG-PET at rest has been at the forefront of functional neuroimaging over the past 3 decades, contributing to the understanding of cognitive functions in healthy humans and how these functional patterns change with cognitive alterations. We discuss methodological considerations that are important for optimizing FDG-PET imaging data prior to analysis. We then highlight the contribution of FDG-PET to the understanding of the patterns of functional differences in non-degenerative pathologies, normal ageing, and age-related neurodegenerative disorders. Through reasonable temporal and spatial resolution, its ability to measure synaptic activity in the whole brain, independently of any specific network and disease, makes it ideal to observe regional functional changes associated with memory impairment. PMID:26319237

  2. Time-Course of Alterations in Myocardial Glucose Utilization in the Zucker Diabetic Fatty (ZDF) Rat with Correlation to Gene Expression of Glucose Transporters: A Small Animal PET Investigation

    PubMed Central

    Shoghi, Kooresh I.; Gropler, Robert J.; Sharp, Terry; Herrero, Pilar; Fettig, Nicole; Su, Yi; Mitra, Mayurranjan S.; Kovacs, Attila; Finck, Brian N.; Welch, Michael J.

    2010-01-01

    Objective Diabetic cardiomyopathy is associated with abnormalities in glucose metabolism. We evaluated myocardial glucose metabolism in a rodent model of Type 2 Diabetes (T2D), namely the Zucker Diabetic Rat (ZDF), and validated PET measures of glucose uptake against gene and protein expression of glucose transporters. Methods Six lean and ZDF rat underwent small animal PET imaging at the age of 14 weeks and at the age of 19 weeks. The imaging protocol consisted of a 60-minute dynamic acquisition with 18FDG (0.5–0.8mCi). Dynamic images were reconstructed using filtered back projection (FBP) with a 2.5 zoom on the heart and 40 frames per imaging session. PET measures of myocardial glucose uptake rate (MGUp) and utilization were determined with an input function derived by the Hybrid Image- Blood Sampling (HIBS) algorithm on recovery-corrected anterolateral myocardial regions of interest. Following the PET imaging session at week 19, hearts were extracted for gene and protein expression analysis of GLUT1 and GLUT4. The dependence of MGUp on gene expression of GLUT1 and GLUT4 was characterized by multiple-regression analysis. Results Compared to lean littermate control rats, MGUp was significantly depressed in ZDF rats at both week 14 and week 19 (P<0.006). Moreover, lean rats at week 19 displayed significantly higher MGUp than week 14 (P=0.007). Consistent with diminished MGUp, gene expression of GLUT4 was significantly (P=0.004) lower in ZDF rats. Finally, MGUp significantly (P=0.0003) correlated with gene expression of GLUT4. Conclusions Using small animal PET, we confirmed alterations in myocardial glucose utilization and validated PET measure of MGUp against gene and protein expression of glucose transporters in the diabetic heart of an animal model of T2D. PMID:18632819

  3. Use of [18F]FDG PET to Monitor The Development of Cardiac Allograft Rejection

    PubMed Central

    Daly, Kevin P.; Dearling, Jason L. J.; Seto, Tatsuichiro; Dunning, Patricia; Fahey, Frederic; Packard, Alan B.; Briscoe, David M.

    2014-01-01

    Background Positron Emission Tomography (PET) has the potential to be a specific, sensitive and quantitative diagnostic test for transplant rejection. To test this hypothesis, we evaluated 18F-labeled fluorodeoxyglucose ([18F]FDG) and 13N-labeled ammonia ([13N]NH3) small animal PET imaging in a well-established murine cardiac rejection model. Methods Heterotopic transplants were performed using minor MHC mismatched B6.C-H2bm12 donor hearts in C57BL/6(H-2b) recipients. C57BL/6 donor hearts into C57BL/6 recipients served as isograft controls. [18F]FDG PET imaging was performed weekly between post-transplant days 7 and 42 and the percent injected dose was computed for each graft. [13N]NH3 imaging was performed to evaluate myocardial perfusion. Results There was a significant increase in [18F]FDG uptake in allografts from day 14 to day 21 (1.6% to 5.2%; P<0.001) and uptake in allografts was significantly increased on post-transplant days 21 (5.2% vs. 0.9%; P=0.005) and 28 (4.8% vs. 0.9%; P=0.006) compared to isograft controls. Furthermore, [18F]FDG uptake correlated with an increase in rejection within allografts between days 14 and 28 post-transplant. Finally, the uptake of [13N]NH3 was significantly lower relative to the native heart in allografts with chronic vasculopathy compared to isograft controls on day 28 (P=0.01). Conclusions PET imaging with [18F]FDG can be used following transplantation to monitor the evolution of rejection. In addition, decreased uptake of [13N]NH3 in rejecting allografts may be reflective of decreased myocardial blood flow. These data suggest that combined [18F]FDG and [13N]NH3 PET imaging could be used as a non-invasive, quantitative technique for serial monitoring of allograft rejection and has potential application in human transplant recipients. PMID:25675207

  4. Guidance for reading FDG PET scans in dementia patients.

    PubMed

    Herholz, K

    2014-12-01

    18F-2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) is a powerful method for detection of disease-related impairment of cerebral glucose metabolism in neurodegenerative diseases. It is of particular interest for early and differential diagnosis of dementia. Reading FDG PET scans requires training to recognise deviations from normal functional brain anatomy and its variations. This paper provides guidance for displaying FDG PET brain scans in a reproducible manner that allows reliable recognition of characteristic disease-related metabolic changes. It also describes typical findings in Alzheimer's disease, Frontotemporal Dementia and Dementia with Lewy Bodies and possible confounding factors, such as vascular changes and brain atrophy. It provides a brief overview on findings in other neurodegenerative diseases and addresses the potential and limitations of software packages for comparison of individual scans with reference data. PMID:25391316

  5. ¹⁸F-FDG-PET/CT in malignant mesothelioma.

    PubMed

    Fuccio, Chiara; Spinapolice, Elena Giulia; Ferretti, Alice; Castellucci, Paolo; Marzola, Maria Cristina; Trifirò, Giuseppe; Rubello, Domenico

    2013-07-01

    It is well known the useful role of ¹⁸F-FDG-PET/CT for differential diagnosis between benign and malignant disease, for staging, for monitoring response and for prognosis regarding mesothelioma. Recently, literature was enriched with new interesting studies regarding the potential applications of ¹⁸F-FDG-PET/CT in this field. The purpose of this review is to evaluate articles published on line (PubMed) from January 2011 until October 2012 in order to obtain an overview of recent progress of molecular imaging in malignant mesothelioma. The main topics concern the use of ¹⁸F-FDG-PET/CT in radiation therapy planning, monitoring of treatment (surgery/chemotherapy) response and prognosis assessment. PMID:23583476

  6. Conversion of arterial input functions for dual pharmacokinetic modeling using Gd-DTPA/MRI and 18F-FDG/PET.

    PubMed

    Poulin, Eric; Lebel, Réjean; Croteau, Etienne; Blanchette, Marie; Tremblay, Luc; Lecomte, Roger; Bentourkia, M'hamed; Lepage, Martin

    2013-03-01

    Reaching the full potential of magnetic resonance imaging (MRI)-positron emission tomography (PET) dual modality systems requires new methodologies in quantitative image analyses. In this study, methods are proposed to convert an arterial input function (AIF) derived from gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) in MRI, into a (18)F-fluorodeoxyglucose ((18)F-FDG) AIF in PET, and vice versa. The AIFs from both modalities were obtained from manual blood sampling in a F98-Fisher glioblastoma rat model. They were well fitted by a convolution of a rectangular function with a biexponential clearance function. The parameters of the biexponential AIF model were found statistically different between MRI and PET. Pharmacokinetic MRI parameters such as the volume transfer constant (K(trans)), the extravascular-extracellular volume fraction (ν(e)), and the blood volume fraction (ν(p)) calculated with the Gd-DTPA AIF and the Gd-DTPA AIF converted from (18)F-FDG AIF normalized with or without blood sample were not statistically different. Similarly, the tumor metabolic rates of glucose (TMRGlc) calculated with (18) F-FDG AIF and with (18) F-FDG AIF obtained from Gd-DTPA AIF were also found not statistically different. In conclusion, only one accurate AIF would be needed for dual MRI-PET pharmacokinetic modeling in small animal models. PMID:22570280

  7. Performance evaluation of the small-animal PET scanner ClairvivoPET using NEMA NU 4-2008 Standards

    NASA Astrophysics Data System (ADS)

    Sato, K.; Shidahara, M.; Watabe, H.; Watanuki, S.; Ishikawa, Y.; Arakawa, Y.; Nai, YH; Furumoto, S.; Tashiro, M.; Shoji, T.; Yanai, K.; Gonda, K.

    2016-01-01

    The aim of this study was to evaluate the performance of ClairvivoPET using NEMA NU4 standards. The ClairvivoPET incorporates a LYSO dual depth-of-interaction detector system with 151 mm axial field of view (FOV). Spatial resolution, sensitivity, counting rate capabilities, and image quality were evaluated using NEMA NU4-2008 standards. Normal mouse imaging was also performed for 10min after intravenous injection of 18F(-)-NaF. Data were compared with 19 other preclinical PET scanners. Spatial resolution measured using full width at half maximum on FBP-ramp reconstructed images was 2.16 mm at radial offset 5 mm of the axial centre FOV. The maximum absolute sensitivity for a point source at the FOV centre was 8.72%. Peak noise equivalent counting rate (NECR) was 415kcps at 14.6MBq ml-1. The uniformity with the image-quality phantom was 4.62%. Spillover ratios in the images of air and water filled chambers were 0.19 and 0.06, respectively. Our results were comparable with the 19 other preclinical PET scanners based on NEMA NU4 standards, with excellent sensitivity because of the large FOV. The ClairvivoPET with iterative reconstruction algorithm also provided sufficient visualization of the mouse spine. The high sensitivity and resolution of the ClairvivoPET scanner provided high quality images for preclinical studies.

  8. Performance evaluation of the small-animal PET scanner ClairvivoPET using NEMA NU 4-2008 Standards.

    PubMed

    Sato, K; Shidahara, M; Watabe, H; Watanuki, S; Ishikawa, Y; Arakawa, Y; Nai, Y H; Furumoto, S; Tashiro, M; Shoji, T; Yanai, K; Gonda, K

    2016-01-21

    The aim of this study was to evaluate the performance of ClairvivoPET using NEMA NU4 standards. The ClairvivoPET incorporates a LYSO dual depth-of-interaction detector system with 151 mm axial field of view (FOV). Spatial resolution, sensitivity, counting rate capabilities, and image quality were evaluated using NEMA NU4-2008 standards. Normal mouse imaging was also performed for 10 min after intravenous injection of (18)F(-)-NaF. Data were compared with 19 other preclinical PET scanners. Spatial resolution measured using full width at half maximum on FBP-ramp reconstructed images was 2.16 mm at radial offset 5 mm of the axial centre FOV. The maximum absolute sensitivity for a point source at the FOV centre was 8.72%. Peak noise equivalent counting rate (NECR) was 415 kcps at 14.6 MBq ml(-1). The uniformity with the image-quality phantom was 4.62%. Spillover ratios in the images of air and water filled chambers were 0.19 and 0.06, respectively. Our results were comparable with the 19 other preclinical PET scanners based on NEMA NU4 standards, with excellent sensitivity because of the large FOV. The ClairvivoPET with iterative reconstruction algorithm also provided sufficient visualization of the mouse spine. The high sensitivity and resolution of the ClairvivoPET scanner provided high quality images for preclinical studies. PMID:26716872

  9. FDG PET/CT Imaging of Prostate Carcinosarcoma.

    PubMed

    Oldan, Jorge Daniel; Chin, Bennett B

    2016-08-01

    We present a case of carcinosarcoma of the prostate. Workup of urinary retention after a previously treated squamous cell carcinoma of the prostate led to a transurethral prostate resection revealing carcinosarcoma of the prostate, which on F-FDG PET/CT demonstrated moderate to high avidity of this atypical prostate cancer, with partial obstruction of the urinary system and lung metastases. While FDG PET is not avid for typical prostatic adenocarcinomas, it should be considered for evaluation of atypical prostate cancers. PMID:27187727

  10. The Basic Principles of FDG-PET/CT Imaging.

    PubMed

    Basu, Sandip; Hess, Søren; Nielsen Braad, Poul-Erik; Olsen, Birgitte Brinkmann; Inglev, Signe; Høilund-Carlsen, Poul Flemming

    2014-10-01

    Positron emission tomography (PET) imaging with 2-[(18)F]fluoro-2-deoxy-D-glucose (FDG) forms the basis of molecular imaging. FDG-PET imaging is a multidisciplinary undertaking that requires close interdisciplinary collaboration in a broad team comprising physicians, technologists, secretaries, radio-chemists, hospital physicists, molecular biologists, engineers, and cyclotron technicians. The aim of this review is to provide a brief overview of important basic issues and considerations pivotal to successful patient examinations, including basic physics, instrumentation, radiochemistry, molecular and cell biology, patient preparation, normal distribution of tracer, and potential interpretive pitfalls. PMID:26050942

  11. A feasibility study of PETiPIX: an ultra high resolution small animal PET scanner

    NASA Astrophysics Data System (ADS)

    Li, K.; Safavi-Naeini, M.; Franklin, D. R.; Petasecca, M.; Guatelli, S.; Rosenfeld, A. B.; Hutton, B. F.; Lerch, M. L. F.

    2013-12-01

    PETiPIX is an ultra high spatial resolution positron emission tomography (PET) scanner designed for imaging mice brains. Four Timepix pixellated silicon detector modules are placed in an edge-on configuration to form a scanner with a field of view (FoV) 15 mm in diameter. Each detector module consists of 256 × 256 pixels with dimensions of 55 × 55 × 300 μm3. Monte Carlo simulations using GEANT4 Application for Tomographic Emission (GATE) were performed to evaluate the feasibility of the PETiPIX design, including estimation of system sensitivity, angular dependence, spatial resolution (point source, hot and cold phantom studies) and evaluation of potential detector shield designs. Initial experimental work also established that scattered photons and recoil electrons could be detected using a single edge-on Timepix detector with a positron source. Simulation results estimate a spatial resolution of 0.26 mm full width at half maximum (FWHM) at the centre of FoV and 0.29 mm FWHM overall spatial resolution with sensitivity of 0.01%, and indicate that a 1.5 mm thick tungsten shield parallel to the detectors will absorb the majority of non-coplanar annihilation photons, significantly reducing the rates of randoms. Results from the simulated phantom studies demonstrate that PETiPIX is a promising design for studies demanding high resolution images of mice brains.

  12. Ga-68-DOTATOC: Feasibility of high throughput screening by small animal PET using a clinical high-resolution PET/CT scanner

    NASA Astrophysics Data System (ADS)

    Hofmann, Michael; Weitzel, Thilo; Krause, Thomas

    2006-12-01

    As radio peptide tracers have been developed in recent years for the high sensitive detection of neuroendocrine tumors, still the broad application of other peptides to breast and prostate cancer is missing. A rapid screening of new peptides can, in theory, be based on in vivo screening in animals by PET/CT. To test this hypothesis and to asses the minimum screening time needed per animal, we used the application of Ga-68-DOTATOC PET/CT in rats as test system. The Ga-68-DOTATOC yields in a hot spot imaging with minimal background. To delineate liver and spleen, we performed PET/CT of 10 animals on a SIEMENS Biograph 16 LSO HIGHREZ after intravenous injection of 1.5 MBq Ga-68-DOTATOC per animal. Animals were mounted in an '18 slot' holding device and scanned for a single-bed position. The emission times for the PET scan was varied from 1 to 20 min. The images were assessed first for "PET only" and afterwards in PET/CT fusion mode. The detection of the two organs was good at emission times down to 1 min in PET/CT fusion mode. In the "PET only" scans, the liver was clearly to be identified down to 1 min emission in all animals. But the spleen could only be delineated only by 1 min of emission in the PET/CT-fusion mode. In conclusion the screening of "hot spot" enriching peptides is feasible. "PET only" is in terms of delineation of small organs by far inferior to PET/CT fusion. If animal tumors are above a diameter of 10 mm small, animal PET/CT using clinical high resolution scanners will enable rapid screening. Even the determination of bio-distributions becomes feasible by using list mode tools. The time for the whole survey of 18 animals including anesthesia, preparation and mounting was approximately 20 min. By use of several holding devices mounted simultaneously, a survey time of less than 1 h for 180 animals can be expected.

  13. Experimental Approach to Evaluate the 11C Perfusion and Diffusion in Small Animal Tissues for HadronPET Applications.

    PubMed

    Martínez-Rovira, Immaculada; Boisgard, Raphaël; Pottier, Géraldine; Kuhnast, Bertrand; Jan, Sébastien

    2016-01-01

    The development of a reliable dose monitoring system in hadron therapy is essential in order to control the treatment plan delivery. Positron Emission Tomography (PET) is the only method used in clinics nowadays for quality assurance. However, the accuracy of this method is limited by the loss of signal due to the biological washout processes. Up to the moment, very few studies measured the washout processes and there is no database of washout data as a function of the tissue and radioisotope. One of the main difficulties is related to the complexity of such measurements, along with the limited time slots available in hadron therapy facilities. Thus, in this work, we proposed an alternative in vivo methodology for the measurement and modeling of the biological washout parameters without any radiative devices. It consists in the implementation of a point-like radioisotope source by direct injection on the tissues of interest and its measurement by means of high-resolution preclinical PET systems. In particular, the washout of 11C carbonate radioisotopes was assessed, considering that 11C is is the most abundant β+ emitter produced by carbon beams. 11C washout measurements were performed in several tissues of interest (brain, muscle and 9L tumor xenograf) in rodents (Wistar rat). Results show that the methodology presented is sensitive to the washout variations depending on the selected tissue. Finally, a first qualitative correlation between 11C tumor washout properties and tumor metabolism (via 18F-FDG tracer uptake) was found. PMID:27015269

  14. Experimental Approach to Evaluate the 11C Perfusion and Diffusion in Small Animal Tissues for HadronPET Applications

    PubMed Central

    Martínez-Rovira, Immaculada; Boisgard, Raphaël; Pottier, Géraldine; Kuhnast, Bertrand; Jan, Sébastien

    2016-01-01

    The development of a reliable dose monitoring system in hadron therapy is essential in order to control the treatment plan delivery. Positron Emission Tomography (PET) is the only method used in clinics nowadays for quality assurance. However, the accuracy of this method is limited by the loss of signal due to the biological washout processes. Up to the moment, very few studies measured the washout processes and there is no database of washout data as a function of the tissue and radioisotope. One of the main difficulties is related to the complexity of such measurements, along with the limited time slots available in hadron therapy facilities. Thus, in this work, we proposed an alternative in vivo methodology for the measurement and modeling of the biological washout parameters without any radiative devices. It consists in the implementation of a point-like radioisotope source by direct injection on the tissues of interest and its measurement by means of high-resolution preclinical PET systems. In particular, the washout of 11C carbonate radioisotopes was assessed, considering that 11C is is the most abundant β+ emitter produced by carbon beams. 11C washout measurements were performed in several tissues of interest (brain, muscle and 9L tumor xenograf) in rodents (Wistar rat). Results show that the methodology presented is sensitive to the washout variations depending on the selected tissue. Finally, a first qualitative correlation between 11C tumor washout properties and tumor metabolism (via 18F-FDG tracer uptake) was found. PMID:27015269

  15. SiliPET: Design of an ultra-high resolution small animal PET scanner based on stacks of semi-conductor detectors

    NASA Astrophysics Data System (ADS)

    Cesca, N.; Auricchio, N.; Di Domenico, G.; Zavattini, G.; Malaguti, R.; Andritschke, R.; Kanbach, G.; Schopper, F.

    2007-03-01

    We studied with Monte Carlo simulations, using the EGSnrc code, a new scanner for small animal positron emission tomography (PET), based on stacks of double-sided semiconductor detectors. Each stack is composed of planar detectors with dimension 70×60×1 mm 3 and orthogonal strips on both sides with 500 μm pitch to read the two interaction coordinates, the third being the detector number in the stack. Multiple interactions in a stack are discarded. In this way, we achieve a precise determination of the first interaction point of the two 511 keV photons. The reduced dimensions of the scanner also improve the solid angle coverage resulting in a high sensitivity. Preliminary results of scanners based on Si planar detectors are presented and the initial tomographic reconstructions demonstrate very good spatial resolution limited only by the positron range. This suggests that, this is a promising new approach for small animal PET imaging. We are testing some double-sided silicon detectors, equipped with 128 orthogonal p and n strips on opposite sides using VATAGP3 ASIC by IDEAS.

  16. FDG PET/CT in Hepatoid Adenocarcinoma of the Lung.

    PubMed

    Wang, Shouyang; Li, Mengxi; Chen, Huai; Li, Jianyu; Zeng, Qingsi

    2016-07-01

    A right upper lung mass was incidentally found on a chest radiograph in a routine health examination in a 56-year-old man. The mass showed mild heterogeneous enhancement on contrast chest CT images and intense FDG uptake on PET/CT images. Pathological examination demonstrated hepatoid adenocarcinoma in the lung. PMID:27124679

  17. FDG-PET/CT of Vulvar Adenocarcinoma With Diffuse Metastases.

    PubMed

    Patel, Darshan; Anderson, Thomas M; Lu, Yang

    2016-09-01

    A 52 year-old woman presented to her gynecologist with a 1-year history of a 1.5-cm left labial mass. Punch biopsy of the vulvar lesion revealed primary infiltrating adenocarcinoma. Staging FDG-PET/CT demonstrated multiorgan diffuse metastases. PMID:27187733

  18. [Interest of FDG-PET for lung cancer radiotherapy].

    PubMed

    Thureau, S; Mezzani-Saillard, S; Modzelewski, R; Edet-Sanson, A; Dubray, B; Vera, P

    2011-10-01

    The recent advances in medical imaging have profoundly altered the radiotherapy of non-small cell lung cancers (NSCLC). A meta-analysis has confirmed the superiority of FDG PET-CT over CT for initial staging. FDG PET-CT improves the reproducibility of target volume delineation, especially close to the mediastinum or in the presence of atelectasia. Although not formally validated by a randomized trial, the reduction of the mediastinal target volume, by restricting the irradiation to FDG-avid nodes, is widely accepted. The optimal method of delineation still remains to be defined. The role of FDG PET-CT in monitoring tumor response during radiotherapy is under investigation, potentially opening the way to adapting the treatment modalities to tumor radiation sensitivity. Other tracers, such as F-miso (hypoxia), are also under clinical investigation. To avoid excessive delays, the integration of PET-CT in routine practice requires quick access to the imaging equipment, technical support (fusion and image processing) and multidisciplinary delineation of target volumes. PMID:21880535

  19. FDG-anorectic parathyroid carcinoma with FDG-avid bone metastasis on PET/CT images.

    PubMed

    Li, Mei; Lu, Hankui; Gao, Yunchao

    2013-11-01

    A 53-year-old man complained of aggravated left hip pain of more than 2 months. Whole-body (18)F-FDG PET/CT revealed only 1 hypermetabolic lesion in the left ilium. Histopathologic examination of the lesion suggested metastatic disease. Blood tests documented mildly elevated blood calcium and parathyroid hormone. Subsequent neck ultrasonography, contrast-enhanced CT, and dual-phase scintigraphy with (99m)Tc-MIBI showed a right parathyroid tumor, which was confirmed to be a parathyroid carcinoma postoperatively. We report a case of parathyroid carcinoma rarely encountered with a FDG-negative primary but a FDG-positive metastasis on PET/CT images. PMID:24089062

  20. Characteristics of a multichannel low-noise front-end ASIC for CZT-based small animal PET imaging

    NASA Astrophysics Data System (ADS)

    Gao, W.; Liu, H.; Gan, B.; Hu, Y.

    2014-05-01

    In this paper, we present the design and characteristics of a novel low-noise front-end readout application-specific integrated circuit dedicated to CdZnTe (CZT) detectors for a small animal PET imaging system. A low-noise readout method based on the charge integration and the delayed peak detection is proposed. An eight-channel front-end readout prototype chip is designed and implemented in a 0.35 μm CMOS process. The die size is 2.3 mm ×2.3 mm. The prototype chip is tested in different methods including electronic test, energy spectrum test and irradiation test. The input range of the ASIC is from 2000e- to 180,000e-, reflecting the energy of the gamma ray from 11.2 keV to 1 MeV. The gain of the readout channel is 65 mV/fC at the shaping time of 1 μs. The best test result of the equivalent noise charge (ENC) is 58.9 e- at zero farad plus 5.4 e- per picofarad. The nonlinearity and the crosstalk are less than 3% and less than 2%, respectively, at the room temperature. The static power dissipation is about 3 mW/channel.

  1. CT with a CMOS flat panel detector integrated on the YAP-(S)PET scanner for in vivo small animal imaging

    NASA Astrophysics Data System (ADS)

    Di Domenico, Giovanni; Cesca, Nicola; Zavattini, Guido; Auricchio, Natalia; Gambaccini, Mauro

    2007-02-01

    Several research groups are pursuing multimodality simultaneous functional and morphological imaging. In this line of research the high resolution YAP-(S)PET small animal integrated PET-SPECT imaging system, constructed by our group of medical physics at the University of Ferrara, is being upgraded with a computed tomography (CT). In this way it will be possible to perform in vivo molecular and genomic imaging studies on small animals (such as mice and rats) and at the same time obtain morphological information necessary for both attenuation correction and accurate localization of the region under investigation. We have take simultaneous PET-CT and SPECT-CT images of phantoms obtained with a single scanner.

  2. Small-animal PET imaging of human epidermal growth factor receptor positive tumor with a 64Cu labeled affibody protein.

    PubMed

    Miao, Zheng; Ren, Gang; Liu, Hongguang; Jiang, Lei; Cheng, Zhen

    2010-05-19

    Epidermal growth factor receptor (EGFR) has become an attractive target for cancer molecular imaging and therapy. Affibody proteins against EGFR have been reported, and thus, we were interested in evaluating their potential for positron emission tomography (PET) imaging of EGFR positive cancer. An Affibody analogue (Ac-Cys-Z(EGFR:1907)) binding to EGFR was made through conventional solid phase peptide synthesis. The purified protein was site-specifically coupled with the 1,4,7,10-tetraazacyclododecane-1,4,7-tris-aceticacid-10-maleimidethylacetamide (maleimido-mono-amide-DOTA) to produce the bioconjugate, DOTA-Z(EGFR:1907). (64)Cu labeled probe (64)Cu-DOTA-Z(EGFR:1907) displayed a moderate specific activity (5-8 MBq/nmol, 22-35 microCi/microg). Cell uptake assays by pre-incubating without or with 300 times excess unlabeled Ac-Cys-Z(EGFR:1907) showed high EGFR-specific uptake (20% applied activity at 0.5 h) in A431 epidermoid carcinoma cancer cells. The affinity (K(D)) of (64)Cu-DOTA-Z(EGFR:1907) as tested by cell saturation analysis was 20 nM. The serum stability test showed excellent stability of the probe with >95% intact after 4 h of incubation in mouse serum. In vivo small-animal PET imaging showed fast tumor targeting, high tumor accumulation (approximately 10% ID/g at 1 h p.i.), and good tumor-to-normal tissue contrast of (64)Cu-DOTA-Z(EGFR:1907) spiked with a wide dose range of Ac-Cys-Z(EGFR:1907). Bio-distribution studies further demonstrated that the probe had high tumor, blood, liver, and kidney uptakes, while blood radioactivity concentration dropped dramatically at increased spiking doses. Co-injection of the probe with 500 microg of Ac-Cys-Z(EGFR:1907) for blocking significantly reduced the tumor uptake. Thus, (64)Cu-DOTA-Z(EGFR:1907) showed potential as a high tumor contrast EGFR PET imaging reagent. The probe spiked with 50 microg of Ac-Cys-Z(EGFR:1907) improved tumor imaging contrast which may have important clinical applications. PMID:20402512

  3. FDG-PET study of patients with Leigh syndrome.

    PubMed

    Haginoya, Kauzhiro; Kaneta, Tomohiro; Togashi, Noriko; Hino-Fukuyo, Naomi; Kobayashi, Tomoko; Uematsu, Mitsugu; Kitamura, Taro; Inui, Takehiko; Okubo, Yukimune; Takezawa, Yusuke; Anzai, Mai; Endo, Wakaba; Miyake, Noriko; Saitsu, Hirotomo; Matsumoto, Naomichi; Kure, Shigeo

    2016-03-15

    We conducted a [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET) study in five patients (median age 11 (range 4-13) years) with Leigh syndrome to evaluate its usefulness for understanding the functional brain dysfunction in this disease and in future drug trials. Four patients were found to have reported mitochondrial DNA gene mutations. The brain T2-weighted magnetic resonance imaging (MRI) showed high-intensity areas in the putamen bilaterally in five patients, caudate bilaterally in four, thalamus bilaterally in two, and brainstem in one. Cerebellar atrophy was observed in older two patients. For disease control, seven age-matched epilepsy patients who had normal MRI and FDG-PET studies were selected. For semiquantitative analysis of the lesions with decreased (18)F-FDG uptake, the mean standard uptake value (SUV) was calculated in regions of interest (ROIs) placed in each brain structure. We compared the SUV of nine segments (the frontal, temporal, parietal, and occipital lobes, thalami, basal ganglia, mid-brain, pons, and cerebellum) between patients with Leigh syndrome and controls. The glucose uptake was decreased significantly in the cerebellum and basal ganglia, which could explain the ataxia and dystonia in patients with Leigh syndrome. Although this study had some limitations, FDG-PET might be useful for evaluating the brain dysfunction and treatment efficacy of new drugs in patients with Leigh syndrome. Further study with more patients using advanced methods to quantify glucose uptake is needed before drawing a conclusion. PMID:26944169

  4. The utility of body FDG PET in staging primary central nervous system lymphoma

    PubMed Central

    Mohile, Nimish A.; DeAngelis, Lisa M.; Abrey, Lauren E.

    2008-01-01

    18F-Fluorodeoxyglucose (FDG) PET has become an important tool in the management of non-Hodgkin’s lymphoma (NHL), but its role in the evaluation of primary CNS lymphoma (PCNSL) has not been established. We investigated the ability of body FDG PET to detect systemic disease in the staging and restaging of PCNSL. The records of 166 PCNSL patients seen at Memorial Sloan-Kettering Cancer Center were examined. Forty-nine patients who underwent body FDG PET for staging of PCNSL were identified. Clinical data were reviewed to determine FDG PET results and their influence on therapy. Body FDG PET disclosed a systemic site of malignancy in 15% of patients. NHL was found in 11% of all patients, 7% of patients at diagnosis, and 27% of patients at CNS relapse. Four percent had a second systemic neoplasm. Workup with conventional staging did not reveal systemic disease, and in 8% of patients, body FDG PET was the only abnormal diagnostic exam suggestive of lymphoma. FDG PET findings altered patient treatment and resulted in additional chemotherapy, surgery, or radiotherapy. Our findings suggest that FDG PET may be more sensitive than conventional body staging and may disclose higher rates of concomitant systemic disease at PCNSL diagnosis. Body FDG PET may be an important noninvasive adjunct to conventional PCNSL staging, and its utility should be evaluated prospectively. PMID:18287338

  5. FDG PET/CT in Peritoneal Metastasis From Prostate Cancer.

    PubMed

    Gungor, Serkan; Asa, Sertac; Kupik, Osman

    2016-09-01

    Prostate cancer is one of the leading causes of cancer death in men. The prognosis in prostate cancer is greatly worsened by the presence of metastases, which are most commonly found in bone, lung, liver, and brain. The peritoneum is an extremely uncommon metastatic site for prostate cancer, even in autopsy series. We present a case of FDG PET/CT demonstration of peritoneal metastasis from prostate cancer. PMID:27187732

  6. Evaluation of Avulsion-Induced Neuropathology in Rat Spinal Cords with 18F-FDG Micro-PET/CT.

    PubMed

    Ling, Ze-Min; Tang, Ying; Li, Ying-Qin; Luo, Hao-Xuan; Liu, Lin-Lin; Tu, Qing-Qiang; Zhou, Li-Hua

    2015-01-01

    Brachial plexus root avulsion (BPRA) leads to dramatic motoneuron death and glial reactions in the corresponding spinal segments at the late stage of injury. To protect spinal motoneurons, assessment of the affected spinal segments should be done at an earlier stage of the injury. In this study, we employed 18F-FDG small-animal PET/CT to assess the severity of BPRA-induced cervical spinal cord injuries. Adult Sprague-Dawley rats were randomly treated and divided into three groups: Av+NS (brachial plexus root avulsion (Av) treated with normal saline), Av+GM1 (treated with monosialoganglioside), and control. At time points of 3 day (d), 1 week (w), 2 w, 4 w and 8 w post-injury, 18F-FDG micro-PET/CT scans and neuropathology assessments of the injured spinal roots, as well as the spinal cord, were performed. The outcomes of the different treatments were compared. The results showed that BPRA induced local bleeding and typical Wallerian degeneration of the avulsed roots accompanied by 18F-FDG accumulations at the ipsilateral cervical intervertebral foramen. BPRA-induced astrocyte reactions and overexpression of neuronal nitric oxide synthase in the motoneurons correlated with higher 18F-FDG uptake in the ipsilateral cervical spinal cord during the first 2 w post-injury. The GM1 treatment reduced BPRA-induced astrocyte reactions and inhibited the de novo nNOS expressions in spinal motoneurons. The GM1 treatment also protected spinal motoneurons from avulsion within the first 4 w post-injury. The data from this study suggest that 18F-FDG PET/CT could be used to assess the severity of BPRA-induced primary and secondary injuries in the spinal cord. Furthermore, GM1 is an effective drug for reducing primary and secondary spinal cord injuries following BPRA. PMID:26010770

  7. Evaluation of Avulsion-Induced Neuropathology in Rat Spinal Cords with 18F-FDG Micro-PET/CT

    PubMed Central

    Li, Ying-Qin; Luo, Hao-Xuan; Liu, Lin-Lin; Tu, Qing-Qiang; Zhou, Li-Hua

    2015-01-01

    Brachial plexus root avulsion (BPRA) leads to dramatic motoneuron death and glial reactions in the corresponding spinal segments at the late stage of injury. To protect spinal motoneurons, assessment of the affected spinal segments should be done at an earlier stage of the injury. In this study, we employed 18F-FDG small-animal PET/CT to assess the severity of BPRA-induced cervical spinal cord injuries. Adult Sprague-Dawley rats were randomly treated and divided into three groups: Av+NS (brachial plexus root avulsion (Av) treated with normal saline), Av+GM1 (treated with monosialoganglioside), and control. At time points of 3 day (d), 1 week (w), 2 w, 4 w and 8 w post-injury, 18F-FDG micro-PET/CT scans and neuropathology assessments of the injured spinal roots, as well as the spinal cord, were performed. The outcomes of the different treatments were compared. The results showed that BPRA induced local bleeding and typical Wallerian degeneration of the avulsed roots accompanied by 18F-FDG accumulations at the ipsilateral cervical intervertebral foramen. BPRA-induced astrocyte reactions and overexpression of neuronal nitric oxide synthase in the motoneurons correlated with higher 18F-FDG uptake in the ipsilateral cervical spinal cord during the first 2 w post-injury. The GM1 treatment reduced BPRA-induced astrocyte reactions and inhibited the de novo nNOS expressions in spinal motoneurons. The GM1 treatment also protected spinal motoneurons from avulsion within the first 4 w post-injury. The data from this study suggest that 18F-FDG PET/CT could be used to assess the severity of BPRA-induced primary and secondary injuries in the spinal cord. Furthermore, GM1 is an effective drug for reducing primary and secondary spinal cord injuries following BPRA. PMID:26010770

  8. Derivation of input function from FDG-PET studies in small hearts

    SciTech Connect

    Wu, Hsiao-Ming; Huang, Sung-Cheng; Allada, V.

    1996-10-01

    The extraction of pure arterial time-activity curves (TACs) from dynamic PET images of a small animal heart using factor analysis of dynamic structures (FADS) was found to be unsuccessful due to the small size of the cardiac chamber that causes extensive mixture of TACs of different structures. In this study, we used digital phantoms of the left ventricle (LV cavity size: 1-2 cm) and small monkey (LV cavity size: {approx} 2 cm) dynamic FDG PET studies to evaluate FADS for extracting the pure blood-pool TACs by adding a single blood sample (taken at a late scan time) constraint. In the digital phantom studies, spillover fractions in the extracted blood-pool TACs using FADS without a blood sample constraint (FADS(-)) and with a blood sample constraint (FADS(+)) were 3%-91% and < 3%, respectively. In the monkey studies (n = 4), FADS(+) extracted blood-pool TACs matched well with the arterialized well counter measurements (% differences of curve integration: FADS(-) < 82%; FADS(+) < 9%). The microparameters (K*{sub 1}, k*{sub 2}, k*{sub 3}, k*{sub 4}) and macroparameters (K{sub nlr}), obtained from the FADS(+) blood-pool TACs, were similar to those obtained from plasma samples in a three-compartment model fitting (% differences of K{sub nlr}: phantom studies < 5%; monkey studies < 9%). The FADS technique with a single-blood sample has the potential to extract the pure blood-pool TACs directly from dynamic PET images of a small animal without multiple blood sampling, region of interest definition or spillover correction. 14 refs., 5 figs., 3 tabs.

  9. FDG and (82)Rb PET/MRI features of brain metastasis of breast cancer.

    PubMed

    Lu, Yang

    2015-06-01

    A 64-year-old woman with stage IV breast cancer underwent an FDG and Rb PET brain studies. The PET brain images were fused with MRI brain T1 post-contrast images. The known enhancing left superoposterior frontal brain metastasis is positive on both FDG Rb PET/MRI images. The Rb PET/MRI showed better target-to-noise ratio, but showed nonspecific uptake in the superior sagittal sinus. PMID:25674864

  10. FDG-MicroPET and Diffusion-Weighted MR Image Evaluation of Early Changes After Radiofrequency Ablation in Implanted VX2 Tumors in Rabbits

    SciTech Connect

    Ohira, Tomohiro Okuma, Tomohisa; Matsuoka, Toshiyuki; Wada, Yasuhiro; Nakamura, Kenji; Watanabe, Yasuyoshi; Inoue, Yuichi

    2009-01-15

    The objective of this study was to evaluate the early changes after radiofrequency ablation (RFA) in VX2 rabbit tumors implanted into the back muscles by diffusion-weighted magnetic resonance (MR) imaging and {sup 18}F-2-fluoro-2-deoxy-D-glucose positron emission tomography ({sup 18}F-FDG PET). Percutaneous CT-guided RFA was conducted in seven rabbits with implanted VX2 tumors. VX2 tumors on the other side were untreated and served as the control. MR imaging was performed with a clinical 1.5-T instrument 2 days after RFA, and FDG-PET, using a high-resolution PET scanner for small animals, was obtained 3 days after the procedure. The mean apparent diffusion coefficient (ADC) values and radioactivity count of untreated and ablated tumors were calculated. Untreated VX2 tumors showed hyperintensity on T1-, T2-, and diffusion-weighted MR images, ring-enhanced on contrast-enhanced T1-weighted imaging, and ring-shaped FDG accumulation on FDG-PET. Ablated VX2 tumors showed slight hyperintensity on T1-, T2-, and diffusion-weighed images, slight enhancement on contrast-enhanced T1-weighted images, and low accumulation on FDG-PET. The ADC value of ablated VX2 tumors (1.52 {+-} 0.24 x 10{sup -3} mm{sup 2}/s) was significantly higher than that of untreated tumors (1.09 {+-} 0.12 x 10{sup -3}; p < 0.05). The tumor/muscle ratio of ablated tumors (0.5 {+-} 0.3) was significantly lower than that of untreated tumors (11.6 {+-} 3.2; p < 0.05). Histopathological examination confirmed the lack of viable tumor cells in the ablated lesions. The results indicate that both ADC value and FDG-PET are potentially useful markers for monitoring the early effects of RFA.

  11. Hepatosplenic Candidiasis Detected by 18F-FDG-PET/CT

    PubMed Central

    Albano, Domenico; Bosio, Giovanni; Bertoli, Mattia; Petrilli, Giulia; Bertagna, Francesco

    2016-01-01

    Hepatosplenic candidiasis is a fungal infection, which mostly affects patients with hematologic malignancies such as leukemia. The pathogenesis of this infection is not clear yet, and the liver is the most commonly affected organ. Diagnosis of hepatosplenic candidiasis can be only established via biopsy, since computed tomography (CT) scan, ultrasonography, and magnetic resonance imaging (MRI) yield non-specific results. The role of fluorine-18 fluorodeoxyglucose positron emission tomography /computed tomography (18F-FDG PET/CT) in diagnosis of hepatosplenic candidiasis remains undetermined, considering a few evidences in the literature. In this case report, we present the case of a 47-year-old patient, affected by acute myeloid leukemia, which was treated with three cycles of chemotherapy, resulting in the development of neutropenia and fever following the last cycle. The 18F-FDG PET/CT scan showed some foci of intense FDG uptake in the liver and spleen. The subsequent diagnostic investigations (i.e., abdominal CT scan and biopsy) were suggestive of hepatosplenic candidiasis. The patient was started on antifungal treatment with fluconazole. After one month, the clinical conditions were resolved, and the subsequent abdominal CT scan was negative.

  12. Hepatosplenic Candidiasis Detected by (18)F-FDG-PET/CT.

    PubMed

    Albano, Domenico; Bosio, Giovanni; Bertoli, Mattia; Petrilli, Giulia; Bertagna, Francesco

    2016-01-01

    Hepatosplenic candidiasis is a fungal infection, which mostly affects patients with hematologic malignancies such as leukemia. The pathogenesis of this infection is not clear yet, and the liver is the most commonly affected organ. Diagnosis of hepatosplenic candidiasis can be only established via biopsy, since computed tomography (CT) scan, ultrasonography, and magnetic resonance imaging (MRI) yield non-specific results. The role of fluorine-18 fluorodeoxyglucose positron emission tomography /computed tomography ((18)F-FDG PET/CT) in diagnosis of hepatosplenic candidiasis remains undetermined, considering a few evidences in the literature. In this case report, we present the case of a 47-year-old patient, affected by acute myeloid leukemia, which was treated with three cycles of chemotherapy, resulting in the development of neutropenia and fever following the last cycle. The (18)F-FDG PET/CT scan showed some foci of intense FDG uptake in the liver and spleen. The subsequent diagnostic investigations (i.e., abdominal CT scan and biopsy) were suggestive of hepatosplenic candidiasis. The patient was started on antifungal treatment with fluconazole. After one month, the clinical conditions were resolved, and the subsequent abdominal CT scan was negative. PMID:27408899

  13. FDG-Avid Portal Vein Tumor Thrombosis from Hepatocellular Carcinoma in Contrast-Enhanced FDG PET/CT

    PubMed Central

    Nguyen, Xuan Canh; Nguyen, Dinh Song Huy; Ngo, Van Tan; Maurea, Simone

    2015-01-01

    Objective(s): In this study, we aimed to describe the characteristics of portal vein tumor thrombosis (PVTT), complicating hepatocellular carcinoma (HCC) in contrast-enhanced FDG PET/CT scan. Methods: In this retrospective study, 9 HCC patients with FDG-avid PVTT were diagnosed by contrast-enhanced fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT), which is a combination of dynamic liver CT scan, multiphase imaging, and whole-body PET scan. PET and CT DICOM images of patients were imported into the PET/CT imaging system for the re-analysis of contrast enhancement and FDG uptake in thrombus, the diameter of the involved portal vein, and characteristics of liver tumors and metastasis. Results: Two patients with previously untreated HCC and 7 cases with previously treated HCC had FDG-avid PVTT in contrast-enhanced FDG PET/CT scan. During the arterial phase of CT scan, portal vein thrombus showed contrast enhancement in 8 out of 9 patients (88.9%). PET scan showed an increased linear FDG uptake along the thrombosed portal vein in all patients. The mean greatest diameter of thrombosed portal veins was 1.8 ± 0.2 cm, which was significantly greater than that observed in normal portal veins (P<0.001). FDG uptake level in portal vein thrombus was significantly higher than that of blood pool in the reference normal portal vein (P=0.001). PVTT was caused by the direct extension of liver tumors. All patients had visible FDG-avid liver tumors in contrast-enhanced images. Five out of 9 patients (55.6%) had no extrahepatic metastasis, 3 cases (33.3%) had metastasis of regional lymph nodes, and 1 case (11.1%) presented with distant metastasis. The median estimated survival time of patients was 5 months. Conclusion: The intraluminal filling defect consistent with thrombous within the portal vein, expansion of the involved portal vein, contrast enhancement, and linear increased FDG uptake of the thrombus extended from liver tumor are findings of FDG

  14. Incidental Detection of Femoral Pseudoaneurysm at 18F-FDG PET/CT.

    PubMed

    Nougaret, Stephanie; Ragucci, Monica; Bach, Ariadne M; Carollo, Gabriella; Mannelli, Lorenzo

    2016-01-01

    A 72-year-old man with history of lung cancer and melanoma was referred for routine follow-up with 18F-FDG PET/CT. CT images showed a new mass in the right groin associated with mild FDG activity on 18F-FDG PET images. Subsequent ultrasound obtained the same day demonstrated flow within the lesion to be a pseudoaneurysm of the right femoral artery. PMID:26462043

  15. Simultaneous scanning of two mice in a small-animal PET scanner: a simulation-based assessment of the signal degradation.

    PubMed

    Reilhac, Anthonin; Boisson, Frédéric; Wimberley, Catriona; Parmar, Arvind; Zahra, David; Hamze, Hasar; Davis, Emma; Arthur, Andrew; Bouillot, Caroline; Charil, Arnaud; Grégoire, Marie-Claude

    2016-02-01

    In PET imaging, research groups have recently proposed different experimental set ups allowing multiple animals to be simultaneously imaged in a scanner in order to reduce the costs and increase the throughput. In those studies, the technical feasibility was demonstrated and the signal degradation caused by additional mice in the FOV characterized, however, the impact of the signal degradation on the outcome of a PET study has not yet been studied. Here we thoroughly investigated, using Monte Carlo simulated [18F]FDG and [11C]Raclopride PET studies, different experimental designs for whole-body and brain acquisitions of two mice and assessed the actual impact on the detection of biological variations as compared to a single-mouse setting. First, we extended the validation of the PET-SORTEO Monte Carlo simulation platform for the simultaneous simulation of two animals. Then, we designed [18F]FDG and [11C]Raclopride input mouse models for the simulation of realistic whole-body and brain PET studies. Simulated studies allowed us to accurately estimate the differences in detection between single- and dual-mode acquisition settings that are purely the result of having two animals in the FOV. Validation results showed that PET-SORTEO accurately reproduced the spatial resolution and noise degradations that were observed with actual dual phantom experiments. The simulated [18F]FDG whole-body study showed that the resolution loss due to the off-center positioning of the mice was the biggest contributing factor in signal degradation at the pixel level and a minimal inter-animal distance as well as the use of reconstruction methods with resolution modeling should be preferred. Dual mode acquisition did not have a major impact on ROI-based analysis except in situations where uptake values in organs from the same subject were compared. The simulated [11C]Raclopride study however showed that dual-mice imaging strongly reduced the sensitivity to variations when mice were

  16. Simultaneous scanning of two mice in a small-animal PET scanner: a simulation-based assessment of the signal degradation

    NASA Astrophysics Data System (ADS)

    Reilhac, Anthonin; Boisson, Frédéric; Wimberley, Catriona; Parmar, Arvind; Zahra, David; Hamze, Hasar; Davis, Emma; Arthur, Andrew; Bouillot, Caroline; Charil, Arnaud; Grégoire, Marie-Claude

    2016-02-01

    In PET imaging, research groups have recently proposed different experimental set ups allowing multiple animals to be simultaneously imaged in a scanner in order to reduce the costs and increase the throughput. In those studies, the technical feasibility was demonstrated and the signal degradation caused by additional mice in the FOV characterized, however, the impact of the signal degradation on the outcome of a PET study has not yet been studied. Here we thoroughly investigated, using Monte Carlo simulated [18F]FDG and [11C]Raclopride PET studies, different experimental designs for whole-body and brain acquisitions of two mice and assessed the actual impact on the detection of biological variations as compared to a single-mouse setting. First, we extended the validation of the PET-SORTEO Monte Carlo simulation platform for the simultaneous simulation of two animals. Then, we designed [18F]FDG and [11C]Raclopride input mouse models for the simulation of realistic whole-body and brain PET studies. Simulated studies allowed us to accurately estimate the differences in detection between single- and dual-mode acquisition settings that are purely the result of having two animals in the FOV. Validation results showed that PET-SORTEO accurately reproduced the spatial resolution and noise degradations that were observed with actual dual phantom experiments. The simulated [18F]FDG whole-body study showed that the resolution loss due to the off-center positioning of the mice was the biggest contributing factor in signal degradation at the pixel level and a minimal inter-animal distance as well as the use of reconstruction methods with resolution modeling should be preferred. Dual mode acquisition did not have a major impact on ROI-based analysis except in situations where uptake values in organs from the same subject were compared. The simulated [11C]Raclopride study however showed that dual-mice imaging strongly reduced the sensitivity to variations when mice were

  17. Sub-millimetre DOI detector based on monolithic LYSO and digital SiPM for a dedicated small-animal PET system.

    PubMed

    Marcinkowski, Radosław; Mollet, Pieter; Van Holen, Roel; Vandenberghe, Stefaan

    2016-03-01

    The mouse model is widely used in a vast range of biomedical and preclinical studies. Thanks to the ability to detect and quantify biological processes at the molecular level in vivo, PET has become a well-established tool in these investigations. However, the need to visualize and quantify radiopharmaceuticals in anatomic structures of millimetre or less requires good spatial resolution and sensitivity from small-animal PET imaging systems.In previous work we have presented a proof-of-concept of a dedicated high-resolution small-animal PET scanner based on thin monolithic scintillator crystals and Digital Photon Counter photosensor. The combination of thin monolithic crystals and MLE positioning algorithm resulted in an excellent spatial resolution of 0.7 mm uniform in the entire field of view (FOV). However, the limitation of the scanner was its low sensitivity due to small thickness of the lutetium-yttrium oxyorthosilicate (LYSO) crystals (2 mm).Here we present an improved detector design for a small-animal PET system that simultaneously achieves higher sensitivity and sustains a sub-millimetre spatial resolution. The proposed detector consists of a 5 mm thick monolithic LYSO crystal optically coupled to a Digital Photon Counter. Mean nearest neighbour (MNN) positioning combined with depth of interaction (DOI) decoding was employed to achieve sub-millimetre spatial resolution. To evaluate detector performance the intrinsic spatial resolution, energy resolution and coincidence resolving time (CRT) were measured. The average intrinsic spatial resolution of the detector was 0.60 mm full-width-at-half-maximum (FWHM). A DOI resolution of 1.66 mm was achieved. The energy resolution was 23% FWHM at 511 keV and CRT of 529 ps were measured. The improved detector design overcomes the sensitivity limitation of the previous design by increasing the nominal sensitivity of the detector block and retains an excellent intrinsic spatial resolution. PMID:26907952

  18. 18F-FDG PET in the Diagnosis and Treatment of Primary Central Nervous System Lymphoma

    PubMed Central

    Yamamoto, Yuka; Nishiyama, Yoshihiro; Tamiya, Takashi

    2013-01-01

    This paper summarizes the usefulness and limitation of positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG) in the diagnosis and treatment of primary central nervous system lymphoma (PCNSL). The 18F-FDG uptake in typical PCNSL is about 2.5 times higher than that in the normal gray matter, and the tumor can usually be identified visually. The 18F-FDG uptake pattern and value provide useful information for differentiating PCNSL from other enhancing malignant brain tumors especially glioblastoma (GB). The 18F-FDG uptake in typical PCNSL is usually homogenous, and the uptake value is significantly higher than that in GB. However, 18F-FDG PET often fails to show the presence of tumor in the brain as 18F-FDG uptake is faint in atypical PCNSL such as disseminated or nonenhancing lesions. 18F-FDG PET is also useful for evaluating the treatment response at a very early stage after the initial treatment. Pretreatment and posttreatment 18F-FDG uptake values may have a prognostic value in patients with PCNSL. In conclusion, 18F-FDG PET is very useful in the diagnosis of typical PCNSL and can differentiate PCNSL from other malignant brain tumors. However, the usefulness of 18F-FDG PET is limited in the diagnosis of atypical PCNSL. PMID:23844359

  19. Monitoring Vasculitis with 18F-FDG PET.

    PubMed

    Bucerius, Jan

    2016-09-01

    Whereas in the past the term "vasculitis" was most frequently used in context with systemic vasculitides, such as the large vessel vasculitides (LVV) Takayasa arteritis and giant cell arteritis, characterized by inflammation of blood vessel walls, it nowadays comprises also inflammatory changes of the vessel wall as a substantial part of the atherosclerotic disease process. Implementing non-invasive imaging techniques, such as computed tomography angiography (CTA), magnetic resonance angiography (MRA) as well as positron emission tomography (PET) in the diagnostic algorithm of atherosclerosis and LVV, depicts a promising step towards an earlier detection with a, consecutively, improved therapeutic approach and potentially prognostic benefit in patients suffering from vasculitis. Mainly molecular imaging with 18F-fluorodeoxyglucose (FDG) PET seems to be promising in offering an early and sensitive identification of inflammatory changes in both, atherosclerosis and LVV. This review will therefore provide an overview on the diagnostic performance and clinical relevance of FDG-PET in monitoring vasculitis in atherosclerosis and LVV, with a focus on LVV. PMID:27280732

  20. Role of FDG PET/CT in Baastrup's disease.

    PubMed

    Subramanyam, Padma; Palaniswamy, Shanmuga Sundaram

    2016-01-01

    Baastrup's disease is a benign condition, which presents as chronic low back pain. It is also known as "kissing spine syndrome" and refers to close approximation of adjacent spinous processes producing inflammation and back pain. This condition is often misdiagnosed, resulting in incorrect treatment and persistence of symptoms. Diagnosis of Baastrup's disease is verified with clinical examination and imaging studies. Conventionally, clinicians resort to magnetic resonance imaging (MRI) of spine rather than X-ray or computed tomography (CT) in the evaluation of back pain. MRI can additionally identify flattening, sclerosis, enlargement, cystic lesions, and bone edema at the articulating surfaces of the two affected spinous processes. Studies have reported that (18)Fluorine fluorodeoxyglucose-positron emission tomography/CT (FDG-PET/CT) can detect a bursitis or an inflammation as a form of stress reaction despite a negative MRI and (99m)Tc Methylene diphosphonate (MDP) bone scan. PET/CT is usually not a recommended investigation for this condition. However, this case report highlights the benefit of FDG-PET/CT in identifying the site of inflammatory pathology. It is also known to identify the exact site of inflammation where steroid or local anesthetic injection can be administered to alleviate pain, especially in patients with multilevel vertebral involvement. PMID:27385901

  1. Role of FDG PET/CT in Baastrup's disease

    PubMed Central

    Subramanyam, Padma; Palaniswamy, Shanmuga Sundaram

    2016-01-01

    Baastrup's disease is a benign condition, which presents as chronic low back pain. It is also known as “kissing spine syndrome” and refers to close approximation of adjacent spinous processes producing inflammation and back pain. This condition is often misdiagnosed, resulting in incorrect treatment and persistence of symptoms. Diagnosis of Baastrup's disease is verified with clinical examination and imaging studies. Conventionally, clinicians resort to magnetic resonance imaging (MRI) of spine rather than X-ray or computed tomography (CT) in the evaluation of back pain. MRI can additionally identify flattening, sclerosis, enlargement, cystic lesions, and bone edema at the articulating surfaces of the two affected spinous processes. Studies have reported that 18Fluorine fluorodeoxyglucose-positron emission tomography/CT (FDG-PET/CT) can detect a bursitis or an inflammation as a form of stress reaction despite a negative MRI and 99mTc Methylene diphosphonate (MDP) bone scan. PET/CT is usually not a recommended investigation for this condition. However, this case report highlights the benefit of FDG-PET/CT in identifying the site of inflammatory pathology. It is also known to identify the exact site of inflammation where steroid or local anesthetic injection can be administered to alleviate pain, especially in patients with multilevel vertebral involvement. PMID:27385901

  2. Parametric dynamic F-18-FDG PET/CT breast imaging

    NASA Astrophysics Data System (ADS)

    Magri, Alphonso; Feiglin, David; Lipson, Edward; Mandel, James; McGraw, Wendy; Lee, Wei; Krol, Andrzej

    2008-03-01

    This study was undertaken to estimate metabolic tissue properties from dynamic breast F-18-FDG PET/CT image series and to display them as 3D parametric images. Each temporal PET series was obtained immediately after injection of 10 mCi of F-18-FDG and consisted of fifty 1- minute frames. Each consecutive frame was nonrigidly registered to the first frame using a finite element method (FEM) based model and fiducial skin markers. Nonlinear curve fitting of activity vs. time based on a realistic two-compartment model was performed for each voxel of the volume. Curve fitting was accomplished by application of the Levenburg-Marquardt algorithm (LMA) that minimized X2. We evaluated which parameters are most suitable to determine the spatial extent and malignancy in suspicious lesions. In addition, Patlak modeling was applied to the data. A mixture model was constructed and provided a classification system for the breast tissue. It produced unbiased estimation of the spatial extent of the lesions. We conclude that nonrigid registration followed by voxel-by-voxel based nonlinear fitting to a realistic two-compartment model yields better quality parametric images, as compared to unprocessed dynamic breast PET time series. By comparison with the mixture model, we established that the total cumulated activity and maximum activity parametric images provide the best delineation of suspicious breast tissue lesions and hyperactive subregions within the lesion that cannot be discerned in unprocessed images.

  3. Comparison of 18F-FDG PET/CT and PET/MRI in patients with multiple myeloma

    PubMed Central

    Sachpekidis, Christos; Hillengass, Jens; Goldschmidt, Hartmut; Mosebach, Jennifer; Pan, Leyun; Schlemmer, Heinz-Peter; Haberkorn, Uwe; Dimitrakopoulou-Strauss, Antonia

    2015-01-01

    PET/MRI represents a promising hybrid imaging modality with several potential clinical applications. Although PET/MRI seems highly attractive in the diagnostic approach of multiple myeloma (MM), its role has not yet been evaluated. The aims of this prospective study are to evaluate the feasibility of 18F-FDG PET/MRI in detection of MM lesions, and to investigate the reproducibility of bone marrow lesions detection and quantitative data of 18F-FDG uptake between the functional (PET) component of PET/CT and PET/MRI in MM patients. The study includes 30 MM patients. All patients initially underwent 18F-FDG PET/CT (60 min p.i.), followed by PET/MRI (120 min p.i.). PET/CT and PET/MRI data were assessed and compared based on qualitative (lesion detection) and quantitative (SUV) evaluation. The hybrid PET/MRI system provided good image quality in all cases without artefacts. PET/MRI identified 65 of the 69 lesions, which were detectable with PET/CT (94.2%). Quantitative PET evaluations showed the following mean values in MM lesions: SUVaverage=5.5 and SUVmax=7.9 for PET/CT; SUVaverage=3.9 and SUVmax=5.8 for PET/MRI. Both SUVaverage and SUVmax were significantly higher on PET/CT than on PET/MRI. Spearman correlation analysis demonstrated a strong correlation between both lesional SUVaverage (r=0.744) and lesional SUVmax (r=0.855) values derived from PET/CT and PET/MRI. Regarding detection of myeloma skeletal lesions, PET/MRI exhibited equivalent performance to PET/CT. In terms of tracer uptake quantitation, a significant correlation between the two techniques was demonstrated, despite the statistically significant differences in lesional SUVs between PET/CT and PET/MRI. PMID:26550538

  4. MRI, enhanced CT, and FDG PET/CT in primary retroperitoneal mucinous cystadenocarcinoma.

    PubMed

    Dong, Aisheng; Zhai, Zhijun; Wang, Yang; Zuo, Changjing

    2015-01-01

    Primary retroperitoneal mucinous cystadenocarcinoma (PRMC) is an extremely rare neoplasm. We present a case of PRMC with MRI, enhanced CT, and FDG PET/CT findings. Abdominal MRI showed a cystic lesion in the retroperitoneum with a mural nodule. The mural nodule showed progressive enhancement on enhanced CT and intense FDG uptake on early PET/CT with increased SUVmax on delayed PET/CT. Laparoscopy was performed. Retroperitoneal mucinous cystadenocarcinoma was confirmed histopathologically. Metastasis from gastrointestinal tract or ovary was excluded. This case indicates, although rare, PRMC should be considered when a hypermetabolic retroperitoneal cystic lesion with bilateral normal ovaries is found on FDG PET/CT. PMID:24445275

  5. FDG-PET/CT based response-adapted treatment

    PubMed Central

    Vriens, Dennis; Arens, Anne I.J.; Hutchings, Martin; Oyen, Wim J.G.

    2012-01-01

    Abstract It has been shown that [18F]fluorodeoxyglucose (FDG)-positron emission tomography (PET) provides robust and reproducible data for early metabolic response assessment in various malignancies. This led to the initiation of several prospective multicenter trials in malignant lymphoma and adenocarcinoma of the esophagogastric junction, in order to investigate whether the use of PET-guided treatment individualization results in a survival benefit. In Hodgkin lymphoma and aggressive non-Hodgkin lymphoma, several trials are ongoing. Some studies aim to investigate the use of PET in early identification of metabolic non-responders in order to intensify treatment to improve survival. Other studies aim at reducing toxicity without adversely affecting cure rates by safely de-escalating therapy in metabolic responders. In solid tumors the first PET response-adjusted treatment trials have been realized in adenocarcinoma of the esophagogastric junction. These trials showed that patients with an early metabolic response to neoadjuvant chemotherapy benefit from this treatment, whereas metabolic non-responders should switch early to surgery, thus reducing the risk of tumor progression during chemotherapy and the risk of toxic death. The trials provide a model for designing response-guided treatment algorithms in other malignancies. PET-guided treatment algorithms are the promise of the near future; the choice of therapy, its intensity, and its duration will become better adjusted to the biology of the individual patient. Today’s major challenge is to investigate the impact on patient outcome of personalized response-adapted treatment concepts. PMID:23023063

  6. Assessment of MR-compatibility of SiPM PET insert using short optical fiber bundles for small animal research

    NASA Astrophysics Data System (ADS)

    Kang, H. G.; Hong, S. J.; Ko, G. B.; Yoon, H. S.; Song, I. C.; Rhee, J. T.; Lee, J. S.

    2015-12-01

    Simultaneous positron emission tomography (PET) and magnetic resonance imaging (MRI) can provide new perspectives in human disease research because of their complementary in-vivo imaging techniques. Previously, we have developed an MR-compatible PET insert based on optical fibers using silicon photomultipliers (SiPM). However when echo planar imaging (EPI) sequence was performed, signal intensity was slowly decreased by -0.9% over the 5.5 minutes and significant geometrical distortion was observed as the PET insert was installed inside an MRI bore, indicating that the PET electronics and its shielding boxes might have been too close to an MR imaging object. In this paper, optical fiber bundles with a length of 54 mm instead of 31 mm were employed to minimize PET interference on MR images. Furthermore, the LYSO crystals with a size of 1.5 × 1.5 × 7.0 mm3 were used instead of 2.47 × 2.74 × 20.0 mm3 for preclinical PET/MR applications. To improve the MR image quality, two receive-only loop coils were used. The effects of the PET insert on the SNR of the MR image either for morphological or advanced MR pulse sequences such as diffusion weighted imaging (DWI), functional MRI (fMRI), and magnetic resonance spectroscopy (MRS) were investigated. The quantitative MR compatibility such as B0 and B1 field homogeneity without PET, with `PET OFF', and with `PET ON' was also evaluated. In conclusion, B0 maps were not affected by the proposed PET insert whereas B1 maps were significantly affected by the PET insert. The advanced MRI sequences such as DWI, EPI, and MRS can be performed without a significant MR image quality degradation.

  7. Spectrum of the Breast Lesions With Increased 18F-FDG Uptake on PET/CT.

    PubMed

    Dong, Aisheng; Wang, Yang; Lu, Jianping; Zuo, Changjing

    2016-07-01

    Interpretation of F-FDG PET/CT studies in breast is challenging owing to nonspecific FDG uptake in various benign and malignant conditions. Benign conditions include breast changes in pregnancy and lactation, gynecomastia, mastitis, fat necrosis, fibroadenoma, intraductal papilloma, and atypical ductal hyperplasia. Among malignancies, invasive ductal carcinoma and invasive lobular carcinoma are common histological types of breast carcinoma. Rarely, other unusual histological types of breast carcinomas (eg, intraductal papillary carcinoma, invasive micropapillary carcinoma, medullary carcinoma, mucinous carcinoma, and metaplastic carcinoma), lymphoma, and metastasis can be the causes. Knowledge of a wide spectrum of hypermetabolic breast lesions on FDG PET/CT is essential in accurate reading of FDG PET/CT. The purpose of this atlas article is to demonstrate features of various breast lesions encountered at our institution, both benign and malignant, which can result in hypermetabolism on FDG PET/CT imaging. PMID:26975010

  8. Spectrum of the Breast Lesions With Increased 18F-FDG Uptake on PET/CT

    PubMed Central

    Dong, Aisheng; Wang, Yang; Lu, Jianping; Zuo, Changjing

    2016-01-01

    Abstract Interpretation of 18F-FDG PET/CT studies in breast is challenging owing to nonspecific FDG uptake in various benign and malignant conditions. Benign conditions include breast changes in pregnancy and lactation, gynecomastia, mastitis, fat necrosis, fibroadenoma, intraductal papilloma, and atypical ductal hyperplasia. Among malignancies, invasive ductal carcinoma and invasive lobular carcinoma are common histological types of breast carcinoma. Rarely, other unusual histological types of breast carcinomas (eg, intraductal papillary carcinoma, invasive micropapillary carcinoma, medullary carcinoma, mucinous carcinoma, and metaplastic carcinoma), lymphoma, and metastasis can be the causes. Knowledge of a wide spectrum of hypermetabolic breast lesions on FDG PET/CT is essential in accurate reading of FDG PET/CT. The purpose of this atlas article is to demonstrate features of various breast lesions encountered at our institution, both benign and malignant, which can result in hypermetabolism on FDG PET/CT imaging. PMID:26975010

  9. Monte Carlo simulations versus experimental measurements in a small animal PET system. A comparison in the NEMA NU 4-2008 framework

    NASA Astrophysics Data System (ADS)

    Popota, F. D.; Aguiar, P.; España, S.; Lois, C.; Udias, J. M.; Ros, D.; Pavia, J.; Gispert, J. D.

    2015-01-01

    In this work a comparison between experimental and simulated data using GATE and PeneloPET Monte Carlo simulation packages is presented. All simulated setups, as well as the experimental measurements, followed exactly the guidelines of the NEMA NU 4-2008 standards using the microPET R4 scanner. The comparison was focused on spatial resolution, sensitivity, scatter fraction and counting rates performance. Both GATE and PeneloPET showed reasonable agreement for the spatial resolution when compared to experimental measurements, although they lead to slight underestimations for the points close to the edge. High accuracy was obtained between experiments and simulations of the system’s sensitivity and scatter fraction for an energy window of 350-650 keV, as well as for the counting rate simulations. The latter was the most complicated test to perform since each code demands different specifications for the characterization of the system’s dead time. Although simulated and experimental results were in excellent agreement for both simulation codes, PeneloPET demanded more information about the behavior of the real data acquisition system. To our knowledge, this constitutes the first validation of these Monte Carlo codes for the full NEMA NU 4-2008 standards for small animal PET imaging systems.

  10. MRI and FDG PET/CT imaging manifestations of cardiac sarcoidosis.

    PubMed

    Lu, Yang; Sweiss, Nadera J

    2015-12-01

    A 52-year-old man had biopsy-proven sarcoidosis of mediastinal lymph nodes. Cardiac sarcoidosis was confirmed on cardiac MRI with typical imaging features as delayed gadolinium enhancement. Follow-up FDG PET/CT with a 3-day pretest diet modification showed suppression of overall myocardial uptake of FDG but with multifocal abnormal FDG uptake in the myocardium regions corresponding to the previous MRI findings. Additional noncardiac active sarcoidosis involving multiple organ and lymph nodes were also visualized on FDG PET/CT. PMID:26544904

  11. FDG cardiac SPECT versus PET: Relation to SPECT radionuclide angiography and thallium scintigraphy

    SciTech Connect

    Srinivasan, G.; Kitsiou, A.N.; Bacharach, S.L.

    1996-05-01

    To determine whether fluorodeoxyglucose (FDG) imaging with SPECT, using high-energy collimation, provides comparable viability information to FDG-PET, 16 pts with chronic CAD undergoing FDG-PET studies were reimaged with SPECT immediately after the PET acquisition was completed. All pts had stress (S)-redistribution (RD)-reinjection (RI) thallium (TL) studies and a subset of 12 pts had SPECT radionuclide angiography (RNA). The LV was divided into 4 long-axis tomograms encompassing the entire LV and the myocardial activity of 11 sectors per tomogram was assessed quantitatively. The mean counts per pixel of corresponding FDG-SPECT, FDG-PET, RD and RI-TL images were normalized to that sector having peak activity on TL-S and compared on the basis of severity of reduction in FDG and TL activity as follows: normal (NI = >85% of peak), mild-moderate (50-86%) and severe (<50%). FDG-SPECT provided concordant viability information with FDG-PET (NI/mild-mod vs severe) in 581 of 615 (94%) sectors and with TL S-RD-RI(NI/reversible/mild-mod vs severe irreversible) in 555 or 615 (90%) sectors. To facilitate comparison of FDG and TK uptake with regional contraction, these sectors were grouped into 5 regions (anterior, septal, apex, inferior and lateral). These data suggest that most normal/HK regions are viable both by FDG and TL. Among a total of 33 sHK and AK/DK regions, in which viability is a clinical concern, 17 (52%) were viable by TL, 22 (67%) by FDG-SPECT and 24 (73%) by FDG-PET (p=NS). These data suggest that most normal/HK regions are viable both by FDG and TL. Among a total of 33 sHK and AK/DK regions, in which viability is a clinical concern, 17 (52%) were viable by TL, 22 (67%) by FDG-SPECT and 24 (73%) by FDG-PET (p=NS). These data affirm the good overall correlation between FDG uptake and TL for differentiating viable from nonviable myocardium in asynergic regions regardless of the technology applied, PET or SPECT.

  12. FDG-PET improves accuracy in distinguishing frontotemporal dementia and Alzheimer's disease.

    PubMed

    Foster, Norman L; Heidebrink, Judith L; Clark, Christopher M; Jagust, William J; Arnold, Steven E; Barbas, Nancy R; DeCarli, Charles S; Turner, R Scott; Koeppe, Robert A; Higdon, Roger; Minoshima, Satoshi

    2007-10-01

    Distinguishing Alzheimer's disease (AD) and frontotemporal dementia (FTD) currently relies on a clinical history and examination, but positron emission tomography with [(18)F] fluorodeoxyglucose (FDG-PET) shows different patterns of hypometabolism in these disorders that might aid differential diagnosis. Six dementia experts with variable FDG-PET experience made independent, forced choice, diagnostic decisions in 45 patients with pathologically confirmed AD (n = 31) or FTD (n = 14) using five separate methods: (1) review of clinical summaries, (2) a diagnostic checklist alone, (3) summary and checklist, (4) transaxial FDG-PET scans and (5) FDG-PET stereotactic surface projection (SSP) metabolic and statistical maps. In addition, we evaluated the effect of the sequential review of a clinical summary followed by SSP. Visual interpretation of SSP images was superior to clinical assessment and had the best inter-rater reliability (mean kappa = 0.78) and diagnostic accuracy (89.6%). It also had the highest specificity (97.6%) and sensitivity (86%), and positive likelihood ratio for FTD (36.5). The addition of FDG-PET to clinical summaries increased diagnostic accuracy and confidence for both AD and FTD. It was particularly helpful when raters were uncertain in their clinical diagnosis. Visual interpretation of FDG-PET after brief training is more reliable and accurate in distinguishing FTD from AD than clinical methods alone. FDG-PET adds important information that appropriately increases diagnostic confidence, even among experienced dementia specialists. PMID:17704526

  13. FDG PET/CT Findings in Abdominal Fat Necrosis After Treatment for Lymphoma.

    PubMed

    Dubreuil, Julien; Moreau, Aurélie; Sarkozy, Clémentine; Traverse-Glehen, Alexandra; Skanjeti, Andrea; Salles, Gilles; Giammarile, Francesco

    2016-05-01

    FDG PET/CT is now validated in non-Hodgkin lymphoma for response assessment in interim and posttreatment lymphoma. We report the case of a 62-year-old man followed by FDG PET/CT for a diffuse large B-cell lymphoma, with initial stage III. The interim FDG PET/CT examination concluded in complete metabolic and morphological response of subdiaphragmatic lymphadenopathy but a persistent abnormal subdiaphragmatic uptake (SUVmax at 9 and Deauville 5-point scale at 5). Therefore, an abdominal biopsy of the corresponding nodules was conducted with a final diagnosis of diffuse fat necrosis. PMID:26825213

  14. Dynamic functional imaging of brain glucose utilization using fPET-FDG

    SciTech Connect

    Villien, Marjorie; Wey, Hsiao-Ying; Mandeville, Joseph B.; Catana, Ciprian; Polimeni, Jonathan R.; Sander, Christin Y.; Zürcher, Nicole R.; Chonde, Daniel B.; Fowler, Joanna S.; Rosen, Bruce R.; Hooker, Jacob M.

    2014-06-14

    We report that glucose is the principal source of energy for the brain and yet the dynamic response of glucose utilization to changes in brain activity is still not fully understood. Positron emission tomography (PET) allows quantitative measurement of glucose metabolism using 2-[18F]-fluorodeoxyglucose (FDG). However, FDG PET in its current form provides an integral (or average) of glucose consumption over tens of minutes and lacks the temporal information to capture physiological alterations associated with changes in brain activity induced by tasks or drug challenges. Traditionally, changes in glucose utilization are inferred by comparing two separate scans, which significantly limits the utility of the method. We report a novel method to track changes in FDG metabolism dynamically, with higher temporal resolution than exists to date and within a single session. Using a constant infusion of FDG, we demonstrate that our technique (termed fPET-FDG) can be used in an analysis pipeline similar to fMRI to define within-session differential metabolic responses. We use visual stimulation to demonstrate the feasibility of this method. Ultimately, this new method has a great potential to be used in research protocols and clinical settings since fPET-FDG imaging can be performed with most PET scanners and data acquisition and analysis are straightforward. fPET-FDG is a highly complementary technique to MRI and provides a rich new way to observe functional changes in brain metabolism.

  15. Dynamic functional imaging of brain glucose utilization using fPET-FDG

    DOE PAGESBeta

    Villien, Marjorie; Wey, Hsiao-Ying; Mandeville, Joseph B.; Catana, Ciprian; Polimeni, Jonathan R.; Sander, Christin Y.; Zürcher, Nicole R.; Chonde, Daniel B.; Fowler, Joanna S.; Rosen, Bruce R.; et al

    2014-06-14

    We report that glucose is the principal source of energy for the brain and yet the dynamic response of glucose utilization to changes in brain activity is still not fully understood. Positron emission tomography (PET) allows quantitative measurement of glucose metabolism using 2-[18F]-fluorodeoxyglucose (FDG). However, FDG PET in its current form provides an integral (or average) of glucose consumption over tens of minutes and lacks the temporal information to capture physiological alterations associated with changes in brain activity induced by tasks or drug challenges. Traditionally, changes in glucose utilization are inferred by comparing two separate scans, which significantly limits themore » utility of the method. We report a novel method to track changes in FDG metabolism dynamically, with higher temporal resolution than exists to date and within a single session. Using a constant infusion of FDG, we demonstrate that our technique (termed fPET-FDG) can be used in an analysis pipeline similar to fMRI to define within-session differential metabolic responses. We use visual stimulation to demonstrate the feasibility of this method. Ultimately, this new method has a great potential to be used in research protocols and clinical settings since fPET-FDG imaging can be performed with most PET scanners and data acquisition and analysis are straightforward. fPET-FDG is a highly complementary technique to MRI and provides a rich new way to observe functional changes in brain metabolism.« less

  16. Measurement of radioactivity concentration in blood by using newly developed ToT LuAG-APD based small animal PET tomograph.

    PubMed

    Malik, Azhar H; Shimazoe, Kenji; Takahashi, Hiroyuki

    2013-01-01

    In order to obtain plasma time activity curve (PTAC), input function for almost all quantitative PET studies, patient blood is sampled manually from the artery or vein which has various drawbacks. Recently a novel compact Time over Threshold (ToT) based Pr:LuAG-APD animal PET tomograph is developed in our laboratory which has 10% energy resolution, 4.2 ns time resolution and 1.76 mm spatial resolution. The measured value of spatial resolution shows much promise for imaging the blood vascular, i.e; artery of diameter 2.3-2.4mm, and hence, to measure PTAC for quantitative PET studies. To find the measurement time required to obtain reasonable counts for image reconstruction, the most important parameter is the sensitivity of the system. Usually small animal PET systems are characterized by using a point source in air. We used Electron Gamma Shower 5 (EGS5) code to simulate a point source at different positions inside the sensitive volume of tomograph and the axial and radial variations in the sensitivity are studied in air and phantom equivalent water cylinder. An average sensitivity difference of 34% in axial direction and 24.6% in radial direction is observed when point source is displaced inside water cylinder instead of air. PMID:24110223

  17. Choline molecular imaging with small-animal PET for monitoring tumor cellular response to photodynamic therapy of cancer

    NASA Astrophysics Data System (ADS)

    Fei, Baowei; Wang, Hesheng; Wu, Chunying; Meyers, Joseph; Xue, Liang-Yan; MacLennan, Gregory; Schluchter, Mark

    2009-02-01

    We are developing and evaluating choline molecular imaging with positron emission tomography (PET) for monitoring tumor response to photodynamic therapy (PDT) in animal models. Human prostate cancer (PC-3) was studied in athymic nude mice. A second-generation photosensitizer Pc 4 was used for PDT in tumor-bearing mice. MicroPET images with 11C-choline were acquired before PDT and 48 h after PDT. Time-activity curves of 11C-choline uptake were analyzed before and after PDT. For treated tumors, normalized choline uptake decreased significantly 48 h after PDT, compared to the same tumors pre-PDT (p <~ 0.001). However, for the control tumors, normalized choline uptake increased significantly (p <~ 0.001). PET imaging with 11C-choline is sensitive to detect early tumor response to PDT in the animal model of human prostate cancer.

  18. Cold wall effect eliminating method to determine the contrast recovery coefficient for small animal PET scanners using the NEMA NU-4 image quality phantom

    NASA Astrophysics Data System (ADS)

    Lajtos, Imre; Czernin, Johannes; Dahlbom, Magnus; Daver, Freddie; Emri, Miklos; Farshchi-Heydari, Salman; Forgacs, Attila; Hoh, Carl K.; Joszai, Istvan; Krizsan, Aron K.; Lantos, Judit; Major, Peter; Molnar, Jozsef; Opposits, Gabor; Tron, Lajos; Vera, David R.; Balkay, Laszlo

    2014-06-01

    The contrast recovery coefficients (CRC) were evaluated for five different small animal PET scanners: GE Explore Vista, Genisys4, MiniPET-2, nanoScan PC and Siemens Inveon. The NEMA NU-4 2008 performance test with the suggested image quality phantom (NU4IQ) does not allow the determination of the CRC values for the hot regions in the phantom. This drawback of NU4IQ phantom motivated us to develop a new method for this purpose. The method includes special acquisition and reconstruction protocols using the original phantom, and results in an artificially merged image enabling the evaluation of CRC values. An advantageous feature of this method is that it stops the cold wall effect from distorting the CRC calculation. Our suggested protocol results in a set of CRC values contributing to the characterization of small animal PET scanners. GATE simulations were also performed to validate the new method and verify the evaluated CRC values. We also demonstrated that the numerical values of this parameter depend on the actual object contrast of the hot region(s) and this mainly comes from the spillover effect. This effect was also studied while analysing the background activity level around the hot rods. We revealed that the calculated background mean values depended on the target contrast in a scanner specific manner. Performing the artificially merged imaging procedure and additional simulations using the micro hollow sphere (MHS) phantom geometry, we also proved that the inactive wall around the hot spheres can have a remarkable impact on the calculated CRC. In conclusion, we have shown that the proposed artificial merging procedure and the commonly used NU4IQ phantom prescribed by the NEMA NU-4 can easily deliver reliable CRC data otherwise unavailable for the NU4IQ phantom in the conventional protocol or the MHS phantom.

  19. (18)F-FDG PET/CT imaging in granulomatosis with polyangiitis.

    PubMed

    De Geeter, Frank; Gykiere, Pieterjan

    2016-01-01

    The paper gives an overview of the literature data on uptake of fluorine-18-fluorodeoxyglucose ((18)F-FDG) into the different tissue lesions which may occur in granulomatosis with polyangiitis (formerly called Wegener's syndrome). It discusses the cellular mechanisms of such (18)F-FDG uptake, which provide a basis for its interpretation in the context of (18)F-FDG positron emission tomography (PET) for inflammatory conditions. PMID:26929934

  20. The Evaluation of Cardiac Sarcoidosis with 18F-FDG PET.

    PubMed

    Al-Faham, Zaid; Jolepalem, Prashant; Oliver Wong, Ching Yee

    2016-06-01

    Cardiac involvement in sarcoidosis is associated with poor prognosis. (18)F-FDG PET can detect the presence of cardiac sarcoidosis, assess disease activity, and serve as a means to monitor treatment response in patients with cardiac sarcoidosis. PMID:26271805

  1. Reproducibility of 18F-FDG PET uptake measurements in head and neck squamous cell carcinoma on both PET/CT and PET/MR

    PubMed Central

    Fischer, B M; Aznar, M C; Hansen, A E; Vogelius, I R; Löfgren, J; Andersen, F L; Loft, A; Kjaer, A; Højgaard, L; Specht, L

    2015-01-01

    Objective: To investigate reproducibility of fluorine-18 fludeoxyglucose (18F-FDG) uptake on 18F-FDG positron emission tomography (PET)/CT and 18F-FDG PET/MR scans in patients with head and neck squamous cell carcinoma (HNSCC). Methods: 30 patients with HNSCC were included in this prospective study. The patients were scanned twice before radiotherapy treatment with both PET/CT and PET/MR. Patients were scanned on the same scanners, 3 days apart and according to the same protocol. Metabolic tumour activity was measured by the maximum and peak standardized uptake value (SUVmax and SUVpeak, respectively), and total lesion glycolysis from the metabolic tumour volume defined from ≥50% SUVmax. Bland–Altman analysis with limits of agreement, coefficient of variation (CV) from the two modalities were performed in order to test the reproducibility. Furthermore, CVs from SUVmax and SUVpeak were compared. The area under the curve from cumulative SUV–volume histograms were measured and tested for reproducibility of the distribution of 18F-FDG uptake. Results: 24 patients had two pre-treatment PET/CT scans and 21 patients had two pre-treatment PET/MR scans available for further analyses. Mean difference for SUVmax, peak and mean was approximately 4% for PET/CT and 3% for PET/MR, with 95% limits of agreement less than ±20%. CV was small (5–7%) for both modalities. There was no significant difference in CVs between PET/CT and PET/MR (p = 0.31). SUVmax was not more reproducible than SUVpeak (p = 0.09). Conclusion: 18F-FDG uptake in PET/CT and PET/MR is highly reproducible and we found no difference in reproducibility between PET/CT and PET/MR. Advances in knowledge: This is the first report to test reproducibility of PET/CT and PET/MR. PMID:25634069

  2. Breast Sparganosis Incidentally Detected by FDG PET/CT.

    PubMed

    Ha, Seunggyun; Oh, So Won; Kim, Yu Kyeong; Yi, Ann; Ahn, Young Joon

    2013-06-01

    Sparganosis is a rare, parasitic infection that is caused by the plercercoid tapeworm larvae of the genus Spirometra. Sparganosis is transmitted by ingestion of larvae-containing water or intermediate hosts, such as raw amphibians, and usually presented with a subcutaneous nodule in the abdominal wall, extremities, and genital organs. Among the various involved organs, the breast is a seldom encountered site for sparganosis. However, breast sparganosis has clinical importance, since it is generally presented with an indolent palpable mass that mimics malignancy, even without evidence of inflammation. Herein, we report a case of breast sparganosis that was detected incidentally by FDG PET/CT during staging work ups in a patient with gall bladder cancer. PMID:24900094

  3. A Case of Lung Squamous Cell Carcinoma With Duodenal Metastasis on FDG PET/CT.

    PubMed

    Cheng, Gang

    2016-08-01

    Non-small cell lung cancer (NSCLC) tends to have distant metastasis. However, metastasis from NSCLC to the small bowel is uncommon, and duodenal metastasis from NSCLC is extremely rare. FDG PET/CT findings of duodenal metastasis from NSCLC have not been reported in the literature. In this case, we report FDG PET/CT findings in a 61-year-old NSCLC patient with biopsy-proven metastasis in the transverse duodenum. PMID:27055139

  4. FDG PET/CT Evidence of Effective Treatment of Cardiac Sarcoidosis With Adalimumab.

    PubMed

    Miller, Christina T; Sweiss, Nadera J; Lu, Yang

    2016-05-01

    A 53-year-old man with mediastinal lymph node biopsy and cardiac MRI-proven cardiac sarcoidosis (CS) received treatment with pacemaker and steroids. FDG PET/CT showed active CS despite treatment with prednisone and methotrexate. Addition of weekly adalimumab (Humira) injections was introduced for 3 months. Follow-up FDG PET/CT showed complete resolution of CS as well as improvement of other sarcoid lesions in the thoracic lymph nodes. PMID:26828145

  5. MRI and FDG-PET/CT imaging in gynecological malignancies: the radiation oncology perspective.

    PubMed

    Fennell, Jamina; Scholber, Jutta; Grosu, Anca L; Volegova-Neher, Natalja; Henne, Karl; Langer, Mathias; Meyer, Philipp T; Gitsch, Gerald; Bartl, Nico

    2016-06-01

    MRI and FDG-PET imaging plays an important role in diagnosis, monitoring and follow-up of gynecological cancer. The goal of this paper was to summarize data of the literature about sensitivity and specificity of MRI and FDG-PET/CT for detection of primary tumor, lymph nodes invasion and metastases in cervix and endometrial cancer and to discuss their implication for radiation treatment planning and monitoring. PMID:26957003

  6. Wavelet denoising in voxel-based parametric estimation of small animal PET images: a systematic evaluation of spatial constraints and noise reduction algorithms

    NASA Astrophysics Data System (ADS)

    Su, Yi; Shoghi, Kooresh I.

    2008-11-01

    Voxel-based estimation of PET images, generally referred to as parametric imaging, can provide invaluable information about the heterogeneity of an imaging agent in a given tissue. Due to high level of noise in dynamic images, however, the estimated parametric image is often noisy and unreliable. Several approaches have been developed to address this challenge, including spatial noise reduction techniques, cluster analysis and spatial constrained weighted nonlinear least-square (SCWNLS) methods. In this study, we develop and test several noise reduction techniques combined with SCWNLS using simulated dynamic PET images. Both spatial smoothing filters and wavelet-based noise reduction techniques are investigated. In addition, 12 different parametric imaging methods are compared using simulated data. With the combination of noise reduction techniques and SCWNLS methods, more accurate parameter estimation can be achieved than with either of the two techniques alone. A less than 10% relative root-mean-square error is achieved with the combined approach in the simulation study. The wavelet denoising based approach is less sensitive to noise and provides more accurate parameter estimation at higher noise levels. Further evaluation of the proposed methods is performed using actual small animal PET datasets. We expect that the proposed method would be useful for cardiac, neurological and oncologic applications.

  7. Feasibility of FDG-PET/CT for the initial diagnosis of papillary thyroid cancer.

    PubMed

    Kim, Heejin; Na, Kyung Jin; Choi, Jae Hyuk; Ahn, Byeong-Cheol; Ahn, Dongbin; Sohn, Jin Ho

    2016-06-01

    To assess the role of [18F]-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET/CT) as a preoperative diagnostic tool in papillary thyroid carcinoma (PTC). From 2011 to 2014, 197 patients with PTC (246 tumor foci in all) underwent FDG-PET. Among these patients, 46 underwent neck dissection for lateral neck metastasis. According to the FDG avidity of the tumor foci or lateral neck metastasis, factors associated with the prognostic value were evaluated by univariate and multivariate logistic regression analyses. Among the 197 patients, 7 (3.6 %) were incidentally found to have non-thyroid origin malignancy. Additionally, 63.0 % (155/246) of PTC foci showed FDG uptake on PET/CT. Univariate analysis showed that the tumor size, the presence of extrathyroidal extension, BRAF mutation, and Hashimoto thyroiditis were associated with FDG avidity. However, except for pathological extrathyroidal extension, the other factors showed statistically significant correlations with FDG avidity (p < 0.001, p = 0.008, and p = 0.009, respectively). FDG uptake in lateral neck node metastasis showed high specificity and negative predictive value (NPV). In four cases of nonspecific findings on ultrasonography (USG)/CT, FDG avidity was helpful to diagnose the presence of lateral neck metastasis. The maximum standardized uptake value (SUVmax) of PET/CT was correlated with the maximum diameter of the involved lateral node. FDG avidity did not show any significance in the recurrence-free survival of both the thyroid tumor and lateral neck metastasis. The FDG avidity of PTC did not show prognostic predictive meaning. However, in the case of lateral neck metastasis, FDG avidity showed high sensitivity and NPV, and could provide better information in cases of nonspecific findings on USG and CT. PMID:25971994

  8. Characterization and optimization of image quality as a function of reconstruction algorithms and parameter settings in a Siemens Inveon small-animal PET scanner using the NEMA NU 4-2008 standards

    NASA Astrophysics Data System (ADS)

    Visser, Eric P.; Disselhorst, Jonathan A.; van Lier, Monique G. J. T. B.; Laverman, Peter; de Jong, Gabie M.; Oyen, Wim J. G.; Boerman, Otto C.

    2011-02-01

    The image reconstruction algorithms provided with the Siemens Inveon small-animal PET scanner are filtered backprojection (FBP), 3-dimensional reprojection (3DRP), ordered subset expectation maximization in 2 or 3 dimensions (OSEM2D/3D) and maximum a posteriori (MAP) reconstruction. This study aimed at optimizing the reconstruction parameter settings with regard to image quality (IQ) as defined by the NEMA NU 4-2008 standards. The NEMA NU 4-2008 image quality phantom was used to determine image noise, expressed as percentage standard deviation in the uniform phantom region (%STD unif), activity recovery coefficients for the FDG-filled rods (RC rod), and spill-over ratios for the non-radioactive water- and air-filled phantom compartments (SOR wat and SOR air). Although not required by NEMA NU 4, we also determined a contrast-to-noise ratio for each rod (CNR rod), expressing the trade-off between activity recovery and image noise. For FBP and 3DRP the cut-off frequency of the applied filters, and for OSEM2D and OSEM3D, the number of iterations was varied. For MAP, the "smoothing parameter" β and the type of uniformity constraint (variance or resolution) were varied. Results of these analyses were demonstrated in images of an FDG-injected rat showing tumours in the liver, and of a mouse injected with an 18F-labeled peptide, showing a small subcutaneous tumour and the cortex structure of the kidneys. Optimum IQ in terms of CNR rod for the small-diameter rods was obtained using MAP with uniform variance and β=0.4. This setting led to RC rod,1 mm=0.21, RC rod,2 mm=0.57, %STD unif=1.38, SOR wat=0.0011, and SOR air=0.00086. However, the highest activity recovery for the smallest rods with still very small %STD unif was obtained using β=0.075, for which these IQ parameters were 0.31, 0.74, 2.67, 0.0041, and 0.0030, respectively. The different settings of reconstruction parameters were clearly reflected in the rat and mouse images as the trade-off between the recovery of

  9. Wavelet-based regularization and edge preservation for submillimetre 3D list-mode reconstruction data from a high resolution small animal PET system

    NASA Astrophysics Data System (ADS)

    de Jesús Ochoa Domínguez, Humberto; Máynez, Leticia Ortega; Villegas, Osslan Osiris Vergara; Castillo, Nelly Gordillo; Sánchez, Vianey Guadalupe Cruz; Casas, Efrén David Gutiérrez

    2011-10-01

    The data obtained from a PET system tend to be noisy because of the limitations of the current instrumentation and the detector efficiency. This problem is particularly severe in images of small animals as the noise contaminates areas of interest within small organs. Therefore, denoising becomes a challenging task. In this paper, a novel wavelet-based regularization and edge preservation method is proposed to reduce such noise. To demonstrate this method, image reconstruction using a small mouse 18F NEMA phantom and a 18F mouse was performed. Investigation on the effects of the image quality was addressed for each reconstruction case. Results show that the proposed method drastically reduces the noise and preserves the image details.

  10. Prognostic value of interim and end-of-treatment FDG-PET in follicular lymphoma: a systematic review.

    PubMed

    Adams, Hugo J A; Nievelstein, Rutger A J; Kwee, Thomas C

    2016-01-01

    This study aimed to systematically review the prognostic value of interim and end-of-treatment (18)F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in follicular lymphoma during and after first-line therapy. The PubMed/MEDLINE database was searched for relevant original studies. Included studies were methodologically assessed, and their results were extracted and descriptively analyzed. Three studies on the prognostic value of interim FDG-PET and eight studies on the prognostic value of end-of-treatment FDG-PET were included. Overall, studies were of poor methodological quality. In addition, there was incomplete reporting of progression-free survival (PFS) and overall survival (OS) data by several studies, and none of the studies incorporated the Follicular Lymphoma International Prognostic Index (FLIPI) in the OS analyses. Two studies reported no significant difference in PFS between interim FDG-PET positive and negative patients, whereas one study reported a significant difference in PFS between the two groups. Two studies reported no significant difference in OS between interim FDG-PET positive and negative patients. Five studies reported end-of-treatment FDG-PET positive patients to have a significantly worse PFS than end-of-treatment FDG-PET negative patients, and one study reported a non-significant trend towards a worse PFS for end-of-treatment FDG-PET positive patients. Three studies reported end-of-treatment FDG-PET positive patients to have a significantly worse OS than end-of-treatment FDG-PET negative patients. In conclusion, the available evidence does not support the use of interim FDG-PET in follicular lymphoma. Although published studies suggest end-of-treatment FDG-PET to be predictive of PFS and OS, they suffer from numerous biases and failure to correct OS prediction for the FLIPI. PMID:26576560

  11. Pharmacological challenge and synaptic response - assessing dopaminergic function in the rat striatum with small animal single-photon emission computed tomography (SPECT) and positron emission tomography (PET).

    PubMed

    Nikolaus, Susanne; Larisch, Rolf; Vosberg, Henning; Beu, Markus; Wirrwar, Andreas; Antke, Christina; Kley, Konstantin; Silva, Maria Angelica De Souza; Huston, Joseph P; Müller, Hans-Wilhelm

    2011-01-01

    Disturbances of dopaminergic neurotransmission may be caused by changes in concentrations of synaptic dopamine (DA) and/or availabilities of pre- and post-synaptic transporter and receptor binding sites. We present a series of experiments which focus on the regulatory mechanisms of the dopamin(DA)ergic synapse in the rat striatum. In these studies, DA transporter (DAT) and/or D(2) receptor binding were assessed with either small animal single-photon emission computed tomography (SPECT) or positron emission tomography (PET) after pharmacological challenge with haloperidol, L-DOPA and methylphenidate, and after nigrostriatal 6-hydroxydopamine lesion. Investigations of DAT binding were performed with [(123)I]N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)nortropane ([(123)I]FP-CIT). D(2) receptor bindingd was assessed with either [(123)I](S)-2-hydroxy-3-iodo-6-methoxy-N-[(1-ethyl-2-pyrrolidinyl)methyl]benzamide ([(123)I]IBZM) or [(18)F]1[3-(4'fluorobenzoyl)propyl]-4-(2-keto-3-methyl-1-benzimidazolinyl)piperidine ([(18)F]FMB). Findings demonstrate that in vivo investigations of transporter and/or receptor binding are feasible with small animal SPECT and PET. Therefore, tracers that are radiolabeled with isotopes of comparatively long half-lives such as (123)I may be employed. Our approach to quantify DAT and/or D(2) receptor binding at baseline and after pharmacological interventions inducing DAT blockade, D(2) receptor blockade, and increases or decreases of endogenous DA concentrations holds promise for the in vivo assessment of synaptic function. This pertains to animal models of diseases associated with pre- or postsynaptic DAergic deficiencies such as Parkinson's disease, Huntington's disease, attention-deficit/hyperactivity disorder, schizophrenia or drug abuse. PMID:22103308

  12. Post-PET ultrasound improves specificity of 18F-FDG-PET for recurrent differentiated thyroid cancer while maintaining sensitivity

    PubMed Central

    Kråkenes, Jostein; Brauckhoff, Katrin; Haugland, Hans Kristian; Heinecke, Achim; Akslen, Lars A; Varhaug, Jan Erik; Brauckhoff, Michael

    2015-01-01

    Background Positron emission tomography (PET) using fluor-18-deoxyglucose (18F-FDG) with or without computed tomography (CT) is generally accepted as the most sensitive imaging modality for diagnosing recurrent differentiated thyroid cancer (DTC) in patients with negative whole body scintigraphy with iodine-131 (I-131). Purpose To assess the potential incremental value of ultrasound (US) over 18F-FDG-PET-CT. Material and Methods Fifty-one consecutive patients with suspected recurrent DTC were prospectively evaluated using the following multimodal imaging protocol: (i) US before PET (pre-US) with or without fine needle biopsy (FNB) of suspicious lesions; (ii) single photon emission computed tomography (≥3 GBq I-131) with co-registered CT (SPECT-CT); (iii) 18F-FDG-PET with co-registered contrast-enhanced CT of the neck; (iv) US in correlation with the other imaging modalities (post-US). Postoperative histology, FNB, and long-term follow-up (median, 2.8 years) were taken as composite gold standard. Results Fifty-eight malignant lesions were identified in 34 patients. Forty lesions were located in the neck or upper mediastinum. On receiver operating characteristics (ROC) analysis, 18F-FDG-PET had a limited lesion-based specificity of 59% at a set sensitivity of 90%. Pre-US had poor sensitivity and specificity of 52% and 53%, respectively, increasing to 85% and 94% on post-US, with knowledge of the PET/CT findings (P < 0.05 vs. PET and pre-US). Multimodal imaging changed therapy in 15 out of 51 patients (30%). Conclusion In patients with suspected recurrent DTC, supplemental targeted US in addition to 18F-FDG-PET-CT increases specificity while maintainin sensitivity, as non-malignant FDG uptake in cervical lesions can be confirmed. PMID:25770086

  13. The value of FDG-PET in the diagnosis of thromboangiitis obliterans--a case series.

    PubMed

    Hackl, Gerald; Milosavljevic, Robert; Belaj, Klara; Gary, Thomas; Rief, Peter; Hafner, Franz; Lipp, Rainer W; Brodmann, Marianne

    2015-04-01

    Thromboangiitis obliterans (TAO) is an inflammatory vascular disease affecting dominantly the vessels of the extremities and is etiologically strongly associated with tobacco consumption. Different imaging techniques are generally used to exclude potential differential diagnoses. We investigated the value of (18) F-flourodeoxyglucose positron emission tomography ([(18) F]FDG-PET) in the diagnosis of TAO. All consecutive patients with diagnosed TAO between Nov 2001 and Nov 2003 at our institution who underwent [(18) F]FDG-PET in the diagnostic workup were analyzed retrospectively. Whole-body scans were conducted after a fasting period of at least 6 h and blood glucose levels lower than 180 mg/dl. The primary endpoint was defined as significantly increased vascular FDG uptake. Tracer uptake was visually determined and, in accordance with strength, divided into grades 0 to 3. In total, ten patients were statistically evaluated. The median patient age at the date of the first [(18) F]FDG-PET was 41.5 years. Repetitive FDG-PET imaging was performed in seven out of ten patients (70 %). The endpoint was objectified in one of the initial examinations (10 %) and in another one out of seven follow-up scans (14.3 %). One positive [(18) F]FDG-PET was observed in the pelvic vessels and the other in the infrapopliteal arteries. Therefore, increased tracer uptake could be observed in two examinations on two different patients (both with grade 3 tracer uptake) out of 17 conducted [(18) F]FDG-PETs in total. The [(18) F]FDG-PET was not a suitable investigative procedure for the diagnosis of TAO in the present patient cohort. PMID:24794493

  14. Performance evaluation of principal component analysis in dynamic FDG-PET studies of recurrent colorectal cancer.

    PubMed

    Thireou, Trias; Strauss, Ludwig G; Dimitrakopoulou-Strauss, Antonia; Kontaxakis, George; Pavlopoulos, Sotiris; Santos, Andres

    2003-01-01

    Performance evaluation of principal component analysis (PCA) of dynamic F-18-FDG-PET studies of patients with recurrent colorectal cancer. Principal component images (PCI) of 17 iteratively reconstructed data sets were visually and quantitatively evaluated. The F-18-FDG compartment model parameters were estimated using polynomial regression. All structures were present in PCI1. PCI2 was correlated with the vascular component and PCI3 with the tumor. The vessel density in the tumor was estimated with a correlation coefficient equal to 0.834. PCA supports the visual interpretation of dynamic F-18-FDG-PET studies, facilitates the application of compartment modeling and is a promising quantification technique. PMID:12573889

  15. Primary Uterine Cervical Lymphoma Manifesting as Menolipsis Staged and Followed Up by FDG PET/CT.

    PubMed

    Zhou, Weiyan; Hua, Fengchun; Zuo, Chuantao; Guan, Yihui

    2016-07-01

    Primary uterine non-Hodgkin's lymphoma of the cervix is rare. We report a 31-year-old woman presented with menolipsis for 8 weeks. Transvaginal ultrasonography and pelvic MRI detected a solid cervical mass invading the adjacent vaginal wall. The lesion showed obvious FDG uptake on PET/CT scan, and malignancy was considered. It proved to be primary diffuse large B-cell lymphoma of the cervix by biopsy. After 6-cycle R-CHOP chemotherapy, no abnormal FDG uptake was found on another FDG PET/CT scan. PMID:27055133

  16. 18F-FDG PET/CT Demonstrating Malignant Degeneration of a Uterine Fibroid.

    PubMed

    Sharma, Punit

    2016-10-01

    Whereas benign leiomyoma of the uterus (fibroid) is very common, malignant degeneration of such fibroids to leiomyosarcoma is rare. Anatomical imaging with CT or MRI cannot differentiate between larger leiomyoma and leiomyosarcoma. Imaging with F-FDG PET/CT can be helpful in differentiating the two. High-grade F-FDG uptake in uterine fibroids is suspected and warrants surgical excision for further evaluation. We present such as case of a 42-year-old premenopausal woman where F-FDG PET/CT helped in making the diagnosis of malignant degeneration of uterine fibroid. PMID:27556790

  17. [A case of hepatocellular carcinoma with multiple lymph node metastases detected by FDG-PET].

    PubMed

    Ito, Tadao; Noguchi, Akinori; Shimizu, Takeshi; Tani, Naoki; Yamaguchi, Masahide; Okano, Shinji; Yamane, Tetsuro; Kawabata, Kenji

    2012-11-01

    We report a case of hepatocellular carcinoma (HCC) with multiple lymph node (LN) metastases. A 68-year-old man underwent hepatectomy at our hospital. Intrahepatic recurrence and swelling of multiple LNs were detected by enhanced CT 21 months later. FDG-PET was positive for multiple swollen LNs, but all were negative for the intrahepatic recurrences. Biopsy of para-aortic LNs was revealed LN metastases from HCC. Immunohistochemically, the LN metastases were composed of poorly differentiated HCC. The sensitivity of FDG-PET in patients with HCC varies in relation to degree of differentiation and decreased FDG uptake must be noted. PMID:23132040

  18. FDG-PET/CT in staging of clear cell odontogenic carcinoma.

    PubMed

    Krishnamoorthy, R; Ravi Kumar, A S; Batstone, M

    2014-11-01

    Clear cell odontogenic carcinoma (CCOC) is a rare neoplasm; only 75 cases have been reported in the English language literature. They have a tendency for recurrence and a capacity to metastasize. There is very little known regarding the metabolic features of this tumour or the utility of fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) scans in the staging and follow-up of these tumours. We present two cases of CCOC with their relevant FDG-PET/CT scan findings. The first patient had primary CCOC of the mandible that was FDG-avid, and the other had recurrence of CCOC of the anterior mandible and superomedial orbit that was not FDG-avid. FDG uptake in CCOC appears to be variable. Although FDG-PET/CT is useful in other head and neck cancers and has benefits compared to other imaging modalities, further studies are needed to investigate the sensitivity of FDG-PET/CT in CCOC. PMID:25015905

  19. FDG PET/CT Findings of Ménétrier Disease.

    PubMed

    Dong, Aisheng; Zhang, Ling; He, Tianlin; Zuo, Changjing

    2016-07-01

    Ménétrier disease is a very rare chronic gastric disorder characterized by gastric mucosal hypertrophy. We present a case of Ménétrier disease with CT, MRI, and FDG PET/CT findings. Enhanced CT and MRI showed diffuse thickened mucosa of the greater curvature and elongated mucosa of the antrum with remarkable enhancement. The early and delayed FDG PET/CT showed increased FDG uptake of these thickened mucosa. The increased FDG uptake may be due to the mucosal inflammation. This case indicates Ménétrier disease should be included in the differential diagnosis of abnormal gastric FDG accumulation along with tumor and nontumor processes. PMID:26825202

  20. Construction and tests of demonstrator modules for a 3-D axial PET system for brain or small animal imaging

    NASA Astrophysics Data System (ADS)

    Beltrame, P.; Bolle, E.; Braem, A.; Casella, C.; Chesi, E.; Clinthorne, N.; Cochran, E.; de Leo, R.; Dissertori, G.; Djambazov, G.; Fanti, V.; Honscheid, K.; Huh, S.; Johnson, I.; Joram, C.; Kagan, H.; Lustermann, W.; Meddi, F.; Nappi, E.; Nessi-Tedaldi, F.; Oliver, J. F.; Pauss, P.; Rafecas, M.; Renker, D.; Rudge, A.; Schinzel, D.; Schneider, T.; Seguinot, J.; Smith, S.; Solevi, P.; Stapnes, S.; Weilhammer, P.

    2011-04-01

    The design and construction of a PET camera module with high sensitivity, full 3-D spatial reconstruction and very good energy resolution is presented. The basic principle consists of an axial arrangement of long scintillation crystals around the Field Of View (FOV), providing a measurement of the transverse coordinates of the interacting 511 keV gamma ray. On top of each layer of crystals, an array of Wave-Length Shifter (WLS) strips, which collect the light leaving the crystals sideways, is positioned orthogonal to the crystal direction. The signals in the WLS strips allow a precise measurement of the z (axial) co-ordinate of the 511 keV γ-ray gamma impact. The construction of two modules used for demonstration of the concept is described. First preliminary results on spatial and energy resolution from one full module will be shown.

  1. Comparison of CE-FDG-PET/CT with CE-FDG-PET/MR in the evaluation of osseous metastases in breast cancer patients

    PubMed Central

    Catalano, O A; Nicolai, E; Rosen, B R; Luongo, A; Catalano, M; Iannace, C; Guimaraes, A; Vangel, M G; Mahmood, U; Soricelli, A; Salvatore, M

    2015-01-01

    Background: Despite improvements in treatments, metastatic breast cancer remains difficult to cure. Bones constitute the most common site of first-time recurrence, occurring in 40–75% of cases. Therefore, evaluation for possible osseous metastases is crucial. Technetium 99 (99Tc) bone scintigraphy and fluorodexossyglucose (FDG) positron emission tomography (PET)-computed tomography (PET-CT) are the most commonly used techniques to assess osseous metastasis. PET magnetic resonance (PET-MR) imaging is an innovative technique still under investigation. We compared the capability of PET-MR to that of same-day PET-CT to assess osseous metastases in patients with breast cancer. Methods: One hundred and nine patients with breast cancer, who underwent same-day contrast enhanced (CE)-PET-CT and CE-PET-MR, were evaluated. CE-PET-CT and CE-PET-MR studies were interpreted by consensus by a radiologist and a nuclear medicine physician. Correlations with prior imaging and follow-up studies were used as the reference standard. Binomial confidence intervals and a χ2 test were used for categorical data, and paired t-test was used for the SUVmax data; a non-informative prior Bayesian approach was used to estimate and compare the specificities. Results: Osseous metastases affected 25 out 109 patients. Metastases were demonstrated by CE-PET-CT in 22 out of 25 patients (88%±7%), and by CE-PET-MR in 25 out of 25 patients (100%). CE-PET-CT revealed 90 osseous metastases and CE-PET-MR revealed 141 osseous metastases (P<0.001). The estimated sensitivity of CE-PET-CT and CE-PET-MR were 0.8519 and 0.9630, respectively. The estimated specificity for CE-FDG-PET-MR was 0.9884. The specificity of CE-PET-CT cannot be determined from patient-level data, because CE-PET-CT yielded a false-positive lesion in a patient who also had other, true metastases. Conclusions: CE-PET-MR detected a higher number of osseous metastases than did same-day CE-PET-CT, and was positive for 12% of the patients

  2. FDG PET with contrast-enhanced CT: a critical imaging tool for laryngeal carcinoma.

    PubMed

    Chu, Mae Mae A Y; Kositwattanarerk, Arpakorn; Lee, David J; Makkar, Jasnit S; Genden, Eric M; Kao, Johnny; Packer, Stuart H; Som, Peter M; Kostakoglu, Lale

    2010-09-01

    Fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) has evolved to be an essential imaging modality in the evaluation of laryngeal carcinoma. Although the modality has limited utility in assessing the extent of the primary tumor, FDG PET has proved to be superior to anatomic modalities in the detection of lymph node and distant metastases. The role of FDG PET in the evaluation of patients with laryngeal tumors that are clinically classified as N0 has not shown consistent usefulness because of the innate resolution limitations of the camera. In the posttherapy setting, however, FDG PET has consistently demonstrated a high negative predictive value in the identification of recurrent disease, both during the course of therapy and during long-term follow-up. In addition, contrast material-enhanced computed tomography (CT) in conjunction with FDG PET has demonstrated a complementary role by allowing for superior anatomic coregistration and therefore more definitive diagnosis. There is sufficient evidence that with further advances in PET technology, this modality will likely become more useful in the detection of small lesions and occult nodal disease, as well as in guiding the management of laryngeal carcinoma. PMID:20833855

  3. Nuclear Medicine Imaging of Infection in Cancer Patients (With Emphasis on FDG-PET)

    PubMed Central

    Vos, Fidel J.; van der Graaf, Winette T.A.; Oyen, Wim J.G.

    2011-01-01

    Infections are a common cause of death and an even more common cause of morbidity in cancer patients. Timely and adequate diagnosis of infection is very important. This article provides clinicians as well as nuclear medicine specialists with a concise summary of the most important and widely available nuclear medicine imaging techniques for infectious and inflammatory diseases in cancer patients with an emphasis on fluorodeoxyglucose positron emission tomography (FDG-PET). 67Ga-citrate has many unfavorable characteristics, and the development of newer radiopharmaceuticals has resulted in the replacement of 67Ga-citrate scintigraphy by scintigraphy with labeled leukocytes or FDG-PET for the majority of conditions. The sensitivity of labeled leukocyte scintigraphy in non-neutropenic cancer patients is comparable with that in patients without malignancy. The specificity, however, is lower because of the uptake of labeled leukocytes in many primary tumors and metastases, most probably as a result of their inflammatory component. In addition, labeled leukocyte scintigraphy cannot be used for febrile neutropenia because of the inability to harvest sufficient peripheral leukocytes for in vitro labeling. FDG-PET has several advantages over these conventional scintigraphic techniques. FDG-PET has shown its usefulness in diagnosing septic thrombophlebitis in cancer patients. It has also been shown that imaging of infectious processes using FDG-PET is possible in patients with severe neutropenia. Although larger prospective studies examining the value of FDG-PET in cancer patients suspected of infection, especially in those with febrile neutropenia, are needed, FDG-PET appears to be the most promising scintigraphic technique for the diagnosis of infection in this patient group. PMID:21680576

  4. Segmental "misty mesentery" on FDG PET/CT: an uncommon manifestation of mesenteric lymphoma.

    PubMed

    Puranik, Ameya D; Purandare, Nilendu C; Agrawal, Archi; Shah, Sneha; Rangarajan, Venkatesh

    2014-01-01

    Mesenteric lymphomas are commonly seen as bulky hypermetabolic nodal masses on F-FDG PET/CT. Very rarely, these are seen as mesenteric haziness due to localized hyperattenuation of fat, known as "misty mesentery", which morphological imaging-wise has other differentials as well. We report a unique imaging finding of segmental misty mesentery with hypermetabolic mesenteric nodes on FDG PET/CT in a patient who was kept on observation due to inconclusive biopsy, which on follow-up imaging progressed to extensive lymphomatous involvement. Thus, in retrospect, this imaging feature on baseline PET/CT was diagnostic for mesenteric lymphoma. PMID:23797224

  5. Extramedullary Involvement of Mast Cell Leukemia Detected by 18F-FDG PET/CT.

    PubMed

    Fu, Zhanli; Zhang, Jin; Liu, Meng; Li, Ziao; Li, Qian

    2016-07-01

    Mast cell leukemia (MCL) is a very rare subtype of systemic mastocytosis, characterized by the leukemic expansion of immature mast cells. We present a case of MCL with extramedullary involvement of cervical lymph node and lung demonstrated by the initial F-FDG PET/CT scan. After a transient complete remission by induction chemotherapy and allogeneic hematopoietic stem cell transplantation, the follow-up PET/CT showed extensive extramedullary relapse involving multiple lymph nodes and small bowel. F-FDG PET/CT may be a useful tool to comprehensively stage and follow-up MCL. PMID:26975014

  6. Primary Liver Carcinosarcoma and 18F-FDG PET/CT.

    PubMed

    Li, Beilei; Zhang, Yiqiu; Hou, Jun; Yu, Haojun; Shi, Hongcheng

    2016-08-01

    Primary liver carcinosarcoma is a very rare, malignant neoplasm that is concomitantly composed of a mixture of sarcomatous and carcinomatous elements. In the present study, an initial staging FDG PET/CT showed intense FDG uptake in a patient with liver carcinosarcoma composed of hepatocellular carcinoma and rhabdomyosarcoma. Two months after surgical resection, a restaging PET/CT showed rapid progression of the disease with abdominal and lung metastases, indicating aggressive feature of the disease. The case shows the importance to repeat a restaging PET/CT at early time after surgery for a patient with liver carcinosarcoma to monitor disease progression. PMID:27280902

  7. fdg-pet in two cases of neurofibromatosis type 1 and atypical malignancies

    PubMed Central

    de Blank, P.; Cole, K.; Kersun, L.; Green, A.; Wilkes, J.J.; Belasco, J.; Bagatell, R.; Bailey, L.C.; Fisher, M.J.

    2014-01-01

    Patients with neurofibromatosis type 1 (nf1) are at increased risk for both benign and malignant tumours, and distinguishing the malignant potential of an individual tumour is a common clinical problem in these patients. Here, we review two cases of uncommon malignancies (Hodgkin lymphoma and mediastinal germ-cell tumour) in patients with nf1. Although 18F-fluorodeoxyglucose positron-emission tomography (fdg-pet) has been used to differentiate benign neurofibromas from malignant peripheral nerve sheath tumours, fdg-pet characteristics for more rare tumours have been poorly described in children with nf1. Here, we report the role of pet imaging in clinical decision-making in each case. In nf1, fdg-pet might be useful in the clinical management of unusual tumour presentations and might help to provide information about the malignant potential of uncommon tumours. PMID:24764718

  8. Evaluation of brain SERT occupancy by resveratrol against MDMA-induced neurobiological and behavioral changes in rats: A 4-[¹⁸F]-ADAM/small-animal PET study.

    PubMed

    Shih, Jui-Hu; Ma, Kuo-Hsing; Chen, Chien-Fu F; Cheng, Cheng-Yi; Pao, Li-Heng; Weng, Shao-Ju; Huang, Yuahn-Sieh; Shiue, Chyng-Yann; Yeh, Ming-Kung; Li, I-Hsun

    2016-01-01

    The misuse of 3,4-methylenedioxymethamphetamine (MDMA) has drawn a growing concern worldwide for its psychophysiological impacts on humans. MDMA abusers are often accompanied by long-term serotonergic neurotoxicity, which is associated with reduced density of cerebral serotonin transporters (SERT) and depressive disorders. Resveratrol (RSV) is a natural polyphenolic phytoalexin that has been known for its antidepressant and neuroprotective effects. However, biological targets of RSV as well as its neuroprotective effects against MDMA remained largely unknown. In this study, we examined binding potency of RSV and MDMA to SERT using small-animal positron emission tomography (PET) with the SERT radioligand, N,N-dimethyl-2-(2-amino-4-[(18)F]fluorophenylthio)benzylamine (4-[(18)F]-ADAM) and investigated the protection of RSV against the acute and long-term adverse effects of MDMA. We found that RSV exhibit binding potentials to SERT in vivo in a dose-dependent manner with variation among brain regions. When the MDMA-treated rats (10mg/kg, s.c.) were co-injected with RSV (20mg/kg, i.p.) twice daily for 4 consecutive days, MDMA-induced acute elevation in plasma corticosterone was significantly reduced. Further, 4-[(18)F]-ADAM PET imaging revealed that RSV protected against the MDMA-induced decrease in SERT availability in the midbrain and the thalamus 2 weeks following the co-treatment. The PET data were comparable to the observation from the forced swim test that RSV sufficiently ameliorated the depressive-like behaviors of the MDMA-treated rats. Together, these findings suggest that RSV is a potential antidepressant and may confer protection against neurobiological and behavioral changes induced by MDMA. PMID:26612383

  9. The Potential Roles of 18F-FDG-PET in Management of Acute Stroke Patients

    PubMed Central

    Bunevicius, Adomas; Yuan, Hong

    2013-01-01

    Extensive efforts have recently been devoted to developing noninvasive imaging tools capable of delineating brain tissue viability (penumbra) during acute ischemic stroke. These efforts could have profound clinical implications for identifying patients who may benefit from tPA beyond the currently approved therapeutic time window and/or patients undergoing neuroendovascular treatments. To date, the DWI/PWI MRI and perfusion CT have received the most attention for identifying ischemic penumbra. However, their routine use in clinical settings remains limited. Preclinical and clinical PET studies with [18F]-fluoro-2-deoxy-D-glucose (18F-FDG) have consistently revealed a decreased 18F-FDG uptake in regions of presumed ischemic core. More importantly, an elevated 18F-FDG uptake in the peri-ischemic regions has been reported, potentially reflecting viable tissues. To this end, this paper provides a comprehensive review of the literature on the utilization of 14C-2-DG and 18F-FDG-PET in experimental as well as human stroke studies. Possible cellular mechanisms and physiological underpinnings attributed to the reported temporal and spatial uptake patterns of 18F-FDG are addressed. Given the wide availability of 18F-FDG in routine clinical settings, 18F-FDG PET may serve as an alternative, non-invasive tool to MRI and CT for the management of acute stroke patients. PMID:23762852

  10. The Effect of Endogenous Adenosine on Neuronal Activity in Rats: An FDG PET Study.

    PubMed

    Parkinson, Fiona E; Paul, Soumen; Zhang, Dali; Mzengeza, Shadreck; Ko, Ji Hyun

    2016-07-01

    2-(18) F-fluorodeoxy-D-glucose (FDG) is a glucose analog that is taken up by cells and phosphorylated. The amount of FDG accumulated by cells is a measure of the rate of glycolysis, which reflects cellular activity. As the levels and actions of the neuromodulator adenosine are dynamically regulated by neuronal activity, this study was designed to test whether endogenous adenosine affects tissue accumulation of FDG as assessed by positron emission tomography (PET) or by postmortem analysis of tissue radioactivity. Rats were given an intraperitoneal injection of the adenosine A1 receptor antagonist 8-cyclopentyl-1,3-dipropyl-xanthine (DPCPX, 3 mg/kg), the adenosine kinase inhibitor ABT-702 (3 mg/kg), or vehicle 10 minutes prior to an intravenous injection of FDG (15.4 ± 0.7 MBq per rat). Rats were then subjected to a 15 minute static PET scan. Reconstructed images were normalized to FDG PET template for rats and standard uptake values (SUVs) were calculated. To examine the regional effect of active treatment compared to vehicle, statistical parametric mapping analysis was performed. Whole-brain FDG uptake was not affected by drug treatment. Significant regional hypometabolism was detected, particularly in cerebellum, of DPCPX- and ABT-702 treated rats, relative to vehicle-treated rats. Thus, endogenous adenosine can affect FDG accumulation although this effect is modest in quiescent rats. PMID:27082948

  11. The Role of 18F-FDG PET/CT Integrated Imaging in Distinguishing Malignant from Benign Pleural Effusion

    PubMed Central

    Sun, Yajuan; Yu, Hongjuan; Ma, Jingquan

    2016-01-01

    Objective The aim of our study was to evaluate the role of 18F-FDG PET/CT integrated imaging in differentiating malignant from benign pleural effusion. Methods A total of 176 patients with pleural effusion who underwent 18F-FDG PET/CT examination to differentiate malignancy from benignancy were retrospectively researched. The images of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging were visually analyzed. The suspected malignant effusion was characterized by the presence of nodular or irregular pleural thickening on CT imaging. Whereas on PET imaging, pleural 18F-FDG uptake higher than mediastinal activity was interpreted as malignant effusion. Images of 18F-FDG PET/CT integrated imaging were interpreted by combining the morphologic feature of pleura on CT imaging with the degree and form of pleural 18F-FDG uptake on PET imaging. Results One hundred and eight patients had malignant effusion, including 86 with pleural metastasis and 22 with pleural mesothelioma, whereas 68 patients had benign effusion. The sensitivities of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging in detecting malignant effusion were 75.0%, 91.7% and 93.5%, respectively, which were 69.8%, 91.9% and 93.0% in distinguishing metastatic effusion. The sensitivity of 18F-FDG PET/CT integrated imaging in detecting malignant effusion was higher than that of CT imaging (p = 0.000). For metastatic effusion, 18F-FDG PET imaging had higher sensitivity (p = 0.000) and better diagnostic consistency with 18F-FDG PET/CT integrated imaging compared with CT imaging (Kappa = 0.917 and Kappa = 0.295, respectively). The specificities of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging were 94.1%, 63.2% and 92.6% in detecting benign effusion. The specificities of CT imaging and 18F-FDG PET/CT integrated imaging were higher than that of 18F-FDG PET imaging (p = 0.000 and p = 0.000, respectively), and CT imaging had better diagnostic consistency with

  12. FDG PET in the evaluation of the aggressiveness of pulmonary adenocarcinoma: correlation with histopathological features.

    PubMed

    Higashi, K; Ueda, Y; Ayabe, K; Sakurai, A; Seki, H; Nambu, Y; Oguchi, M; Shikata, H; Taki, S; Tonami, H; Katsuda, S; Yamamoto, I

    2000-08-01

    2-[Fluorine-18]fluoro-2-deoxy-d-glucose (FDG) uptake within the primary lesion correlates with survival on positron emission tomography (PET) studies of patients with non-small cell lung cancer. The more metabolically active the tumour, the worse the outcome. The aim of this study was to determine whether a correlation exists between aggressiveness as determined by pathology and the findings of FDG PET in pulmonary adenocarcinoma. Thirty-five patients with 38 adenocarcinomas of the lung were studied. All patients underwent thoracotomy within 4 weeks of the FDG PET study. For semiquantitative analysis, standardized uptake values (SUVs) were calculated. Patients were classified into high SUV (> or = 4.0) and low SUV (<4.0) groups. The degree of FDG uptake (SUVs) in primary lung lesions was correlated with the histopathological features of aggressiveness (pleural involvement, vascular invasion or lymphatic permeation). The mean SUV of aggressive adenocarcinomas (4.36+/-1.94, n = 22) was higher than that of non-aggressive ones (1.53+/-0.88, n = 16) (P < 0.0001). Tumours with a high FDG uptake have a significantly higher likelihood of aggressiveness than those with a low FDG uptake (P = 0.0004). Analysis by the Kaplan-Meier methods revealed that the groups had different prognoses (log-rank test, P = 0.0099). The high SUV group had a significantly worse prognosis. In conclusion, a correlation was seen between aggressiveness as determined by pathology and glucose metabolism as measured by FDG PET in adenocarcinoma of the lung. FDG PET may be used as a non-invasive diagnostic technique in measuring aggressiveness and prognosis in patients with pulmonary adenocarcinoma. PMID:11039452

  13. Clinical significance of incidental FDG uptake in the prostate gland detected by PET/CT

    PubMed Central

    Sahin, Ertan; Elboga, Umut; Kalender, Ebuzer; Basıbuyuk, Mustafa; Demir, Hasan Deniz; Celen, Yusuf Zeki

    2015-01-01

    The value of FDG-positron emission tomography/computed tomography (PET/CT) for detecting prostate cancer is unknown. We aimed to investigate the clinical value of incidental prostate FDG uptake on PET/CT scans. We reviewed 6128 male patients who underwent FDG-PET/CT scans and selected cases that reported hypermetabolic lesion in the prostate. The patients who have prior history of prostate carcinoma or prostate surgery were excluded from the study. We have analyzed the correlation between PET/CT findings and serum prostate-specific antigen (PSA) levels, imaging (USG), urological examinations and biopsy. Incidental 18F-FDG uptake of the prostate gland was observed in 79 patients (1.3%). While sixteen of them were excluded due to inadequate clinical data, the remaining 63 patients were included for further analysis. The patients were divided into two groups; 8 patients (12.7%) in the malignant group and 55 patients (87.3%) in the benign group. The SUVmax values were not significantly different between the two groups. In 6 (75%) patients with prostate cancer, FDG uptake was observed focally in the peripheral zone of the prostate glands. There was no significant correlation between the SUVmax and the PSA levels. Incidental 18F-FDG uptake in the prostate gland is a rare condition, but a substantial portion of it is associated with the cancer. Benign and malignant lesions of the prostate gland in FDG-PET/CT imaging could not be reliably distinguished. The peripheral focally FDG uptake of prostate glands should be further examined with the clinical and labaratory evaluations. PMID:26379847

  14. [Technical Approaches for Quantitative Treatment Responses Using 18F-FDG PET].

    PubMed

    Miwa, Kenta; Miyaji, Noriaki; Umeda, Takuro; Murata, Taisuke; Wagatsuma, Kei; Sasaki, Masayuki

    2015-01-01

    Quantitative assessment of 18F-FDG PET can predict treatment responses or outcomes. Here, I briefly describe some world trends in standardizing PET images for image-based assessments of treatment responses, followed by present and future strategies for defining the optimal acquisition conditions for quantitative PET imaging. Finally, information is provided about new technical approaches to improving the quantitation of semi-quantitative indexes such as point spread function, time-of-flight and respiratory gating. PMID:26753394

  15. Hybrid 18F-FDG PET-MRI of the hand in rheumatoid arthritis: initial results.

    PubMed

    Miese, Falk; Scherer, Axel; Ostendorf, Benedikt; Heinzel, Alexander; Lanzman, Rotem S; Kröpil, Patric; Blondin, Dirk; Hautzel, Hubertus; Wittsack, Hans-Jörg; Schneider, Matthias; Antoch, Gerald; Herzog, Hans; Shah, N Jon

    2011-09-01

    18F-fluorodeoxyglucose PET (18F-FDG PET) is highly sensitive to inflammatory changes within the synovial tissue in rheumatoid arthritis (RA). However, the highest spatial resolution for soft tissue can be achieved with MRI. Here, we report on the first true hybrid PET-MRI examination of the hand in early RA exploiting the advantages of both modalities. PET-MRI was performed with a prototype of an APD-based magneto-insensitive BrainPET detector (Siemens Healthcare, Erlangen, Germany) operated within a standard 3T MR scanner (MAGNETOM Trio, Siemens). PET images were normalized, random, attenuation and scatter-corrected, iteratively reconstructed and calibrated to yield standardized uptake values (SUV) of 18F-FDG uptake. T1-weighted TSE in coronal as well as sagittal orientation prior to and following Gadolinium administration were acquired. Increased 18F-FDG uptake was present in synovitis and tenovaginitis as identified on contrast-enhanced MRI. The tracer distribution was surrounding the metacarpophalangeal joints II and III. Maximum SUV of 3.1 was noted. In RA, true hybrid 18F-FDG PET-MRI of the hand is technically feasible and bears the potential to directly visualize inflammation. PMID:21590292

  16. Does Delayed-Time-Point Imaging Improve 18F-FDG-PET in Patients With MALT Lymphoma?

    PubMed Central

    Mayerhoefer, Marius E.; Giraudo, Chiara; Senn, Daniela; Hartenbach, Markus; Weber, Michael; Rausch, Ivo; Kiesewetter, Barbara; Herold, Christian J.; Hacker, Marcus; Pones, Matthias; Simonitsch-Klupp, Ingrid; Müllauer, Leonhard; Dolak, Werner; Lukas, Julius; Raderer, Markus

    2016-01-01

    Purpose To determine whether in patients with extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue lymphoma (MALT), delayed–time-point 2-18F-fluoro-2-deoxy-d-glucose-positron emission tomography (18F-FDG-PET) performs better than standard–time-point 18F-FDG-PET. Materials and Methods Patients with untreated histologically verified MALT lymphoma, who were undergoing pretherapeutic 18F-FDG-PET/computed tomography (CT) and consecutive 18F-FDG-PET/magnetic resonance imaging (MRI), using a single 18F-FDG injection, in the course of a larger-scale prospective trial, were included. Region-based sensitivity and specificity, and patient-based sensitivity of the respective 18F-FDG-PET scans at time points 1 (45–60 minutes after tracer injection, TP1) and 2 (100–150 minutes after tracer injection, TP2), relative to the reference standard, were calculated. Lesion-to-liver and lesion-to-blood SUVmax (maximum standardized uptake values) ratios were also assessed. Results 18F-FDG-PET at TP1 was true positive in 15 o f 23 involved regions, and 18F-FDG-PET at TP2 was true-positive in 20 of 23 involved regions; no false-positive regions were noted. Accordingly, region-based sensitivities and specificities were 65.2% (confidence interval [CI], 45.73%–84.67%) and 100% (CI, 100%-100%) for 18F-FDG-PET at TP1; and 87.0% (CI, 73.26%–100%) and 100% (CI, 100%-100%) for 18F-FDG-PET at TP2, respectively. FDG-PET at TP1 detected lymphoma in at least one nodal or extranodal region in 7 of 13 patients, and 18F-FDG-PET at TP2 in 10 of 13 patients; accordingly, patient-based sensitivity was 53.8% (CI, 26.7%–80.9%) for 18F-FDG-PET at TP1, and 76.9% (CI, 54.0%–99.8%) for 18F-FDG-PET at TP2. Lesion-to-liver and lesion-to-blood maximum standardized uptake value ratios were significantly lower at TP1 (ratios, 1.05 ± 0.40 and 1.52 ± 0.62) than at TP2 (ratios, 1.67 ± 0.74 and 2.56 ± 1.10; P = 0.003 and P = 0.001). Conclusions Delayed–time-point imaging

  17. 11C-Choline and FDG PET/CT Imaging of Primary Cholangiocarcinoma: A Comparative Analysis

    PubMed Central

    Chotipanich, Chanisa; Promteangtrong, Chetsadaporn; Kunawudhi, Anchisa; Chanwat, Rawisak; Sricharunrat, Thaniya; Suratako, Savitree; Wongsa, Paramest

    2015-01-01

    Objective(s): This study aimed to compare the diagnostic values of 11C-choline and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in patients with cholangiocarcinoma (CCA). Methods: This prospective study was conducted on 10 patients (6 males and 4 females), aged 42-69 years, suspected of having CCA based on CT or magnetic resonance imaging (MRI) results. 11C-choline and 18F-FDG PET/CT studies were performed in all patients over 1 week. PET/CT results were visually analyzed by 2 independent nuclear medicine physicians and quantitatively by calculating the tumor-to-background ratio (T/B). Results: No 11C-choline PET/CT uptake was observed in primary extrahepatic or intrahepatic CCA cases. Intense 18F-FDG avidity was detected in the tumors of 8 patients (%80). Two patients, who were 18F-FDG negative, had primary extrahepatic CCA. Ki-67 measurements were positive in all patients (range; 14.2%-39.9%). The average T/B values of 11C-choline and 18F-FDG were 0.4±0.2 and 2.0±1.0 in all cases of primary CCA, respectively; these values were significantly lower for 11C-choline (P<0.005). Both FDG and 11C-choline PET/CT detected metastatic CCA foci in all 8 patients (two patients had no metastases). Conclusion: As the results suggested, primary CCA lesions showed a poor avidity for 11C-choline, whereas 18F-FDG PET/CT was of value for the detection of most primary CCA cases. In contrast to primary lesions, metastatic CCA lesions showed 11C-choline avidity.

  18. Correlation of PET and AMS analyses for early kinetics of 2-fluoro-2-deoxyglucose (FDG)

    NASA Astrophysics Data System (ADS)

    Minamimoto, Ryogo; Hamabe, Yoshimi; Miyaoka, Teiji; Theeraladanon, Chumpol; Oka, Takashi; Matsui, Takao; Inoue, Tomio

    2010-04-01

    The draft of the guidelines for microdosing in clinical trials was published in Japan in 2008 following the guidelines of the European Medicines Agency (EMEA) and the Food and Drug Administration (FDA). It recommends utilizing accelerator mass spectrometry (AMS), liquid chromatography/mass spectrometry (LC/MS/MS), and positron emission tomography (PET) for monitoring drug metabolites in preclinical studies. In this study, we clarified the correlation in measuring result between PET and AMS. The AMS measurement was undergone by using AMS system of Institute of Accelerator Analysis Ltd. (IAA, Kawasaki, Japan). First the back ground 14C level of blood in mice was measured by AMS. Second, we clarified the relationship between AMS and PET by using 2-fluoro-2-deoxyglucose (FDG). The correlation coefficient ( r) of the measurements using PET ( 18F-FDG) and AMS ( 14C-FDG) were quite high at 0.97 ( Y = 7.54 E - 05 X + 0.02, p < 0.001). The blood clearance profile of 18F-FDG was nearly identical with that of 14C-FDG. These results indicate that the AMS analysis has excellent correlation with the PET method.

  19. Optimal feature selection for automated classification of FDG-PET in patients with suspected dementia

    NASA Astrophysics Data System (ADS)

    Serag, Ahmed; Wenzel, Fabian; Thiele, Frank; Buchert, Ralph; Young, Stewart

    2009-02-01

    FDG-PET is increasingly used for the evaluation of dementia patients, as major neurodegenerative disorders, such as Alzheimer's disease (AD), Lewy body dementia (LBD), and Frontotemporal dementia (FTD), have been shown to induce specific patterns of regional hypo-metabolism. However, the interpretation of FDG-PET images of patients with suspected dementia is not straightforward, since patients are imaged at different stages of progression of neurodegenerative disease, and the indications of reduced metabolism due to neurodegenerative disease appear slowly over time. Furthermore, different diseases can cause rather similar patterns of hypo-metabolism. Therefore, classification of FDG-PET images of patients with suspected dementia may lead to misdiagnosis. This work aims to find an optimal subset of features for automated classification, in order to improve classification accuracy of FDG-PET images in patients with suspected dementia. A novel feature selection method is proposed, and performance is compared to existing methods. The proposed approach adopts a combination of balanced class distributions and feature selection methods. This is demonstrated to provide high classification accuracy for classification of FDG-PET brain images of normal controls and dementia patients, comparable with alternative approaches, and provides a compact set of features selected.

  20. [SPECT and FDG-PET in diagnostics of neurolues].

    PubMed

    Pichler, Robert; Doppler, Stefan; Szalay, Elisabeth; Hertl, Christine; Knell, Ulrich; Winkler, Johanna

    2008-01-01

    Syphilis is a recurrent treponematosis of acute and chronic evolution. In general it is either sexually or congenitally transmitted. Primary syphilis appears as a single and painless lesion. Secondary syphilis may manifest years later, the secondary bacteremic stage is accompanied by generalized mucocutaneous lesions. Tertiary disease can be disseminated to bones and virtually any organ, involving principally the ascending aorta and the central nervous system. Nuclear medicine provides diagnostic methods in case of skeletal manifestations by bone scan - identifying periostitis and osteomyelitis. Hepatic gummas can be imaged by 99m-Tc-colloid liver scintigraphy. In neurosyphilis brain perfusion SPECT enables imaging of cerebral involvement by small vessel endarteritis resulting from syphilitic vascular disease. 18-FDG PET is also useful to evaluate neurosyphilis, a reduction of brain glucose consumption is observed. The technique adequately enables imaging of therapeutic response and might be superior to morphologic imaging. We present our experiences with these nuclear medicine methods in patients with neurolues. The incidence of neurolues is estimated at 2 per 100.000 inhabitants worldwide, migration processes might bring a re-emergence of this disease to Austria and other developed countries of the EU. Scintigraphic methods should be kept in mind for diagnostic evaluation of neurosyphilis. PMID:19066767

  1. Exploring Small Animal Care. Teacher's Guide.

    ERIC Educational Resources Information Center

    Livesey, Dennis W.

    This course guide in small animal care is designed to give students seeking employment in veterinary hospitals, kennels, or pet shops an opportunity to (1) develop basic skills in small animal handling, sanitation of housing, and nutrition, (2) acquire skills in dog and cat grooming, including shop operation, (3) develop attitudes which contribute…

  2. High School Small Animal Laboratory--Business

    ERIC Educational Resources Information Center

    Penn, Alan

    1974-01-01

    An Ohio vocational school Small Animal Care program prepares students for entry level employment as veterinary assistants, pet shop salesmen, kennel workers, animal groomers, Humane Society workers, laboratory animal assistants, and riding stable assistants. (EA)

  3. 18F-FDG PET/CT Prediction of an Aggressive Clinical Course for Dermatofibrosarcoma Protuberans.

    PubMed

    Basu, Sandip; Goliwale, Fahim

    2016-06-01

    The ability to assess tumor biology is a benefit of molecular imaging with (18)F-FDG PET/CT, which performs better than anatomic imaging in evaluating malignancies. We present an unusual case of fatal dermatofibrosarcoma protuberans, a usually indolent entity for which high-grade (18)F-FDG uptake was predictive of an aggressive clinical course unabated by tyrosine kinase inhibitor imatinib mesylate, to which the patient showed a poor response. PMID:26338485

  4. Basic performance evaluation of a Si-PM array-based LGSO phoswich DOI block detector for a high-resolution small animal PET system.

    PubMed

    Yamamoto, Seiichi

    2013-07-01

    The silicon photomultiplier (Si-PM) is a promising photodetector for PET. However, it remains unclear whether Si-PM can be used for a depth-of-interaction (DOI) detector based on the decay time differences of the scintillator where pulse shape analysis is used. For clarification, we tested the Hamamatsu 4 × 4 Si-PM array (S11065-025P) combined with scintillators that used different decay times to develop DOI block detectors using the pulse shape analysis. First, Ce-doped Gd(2)SiO(5) (GSO) scintillators of 0.5 mol% Ce were arranged in a 4 × 4 matrix and were optically coupled to the center of each pixel of the Si-PM array for measurement of the energy resolution as well as its gain variations according to the temperature. Then two types of Ce-doped Lu(1.9)Gd(0.1)Si0(5) (LGSO) scintillators, 0.025 mol% Ce (decay time: ~31 ns) and 0.75 mol% Ce (decay time: ~46 ns), were optically coupled in the DOI direction, arranged in a 11 × 7 matrix, and optically coupled to a Si-PM array for testing of the possibility of a high-resolution DOI detector. The energy resolution of the Si-PM array-based GSO block detector was 18 ± 4.4 % FWHM for a Cs-137 gamma source (662 keV). Less than 1 mm crystals were clearly resolved in the position map of the LGSO DOI block detector. The peak-to-valley ratio (P/V) derived from the pulse shape spectra of the LGSO DOI block detector was 2.2. These results confirmed that Si-PM array-based DOI block detectors are promising for high-resolution small animal PET systems. PMID:23271446

  5. Detection of prostate cancer by an FDG-PET cancer screening program: results from a Japanese nationwide survey

    PubMed Central

    Minamimoto, Ryogo; Senda, Michio; Jinnouchi, Seishi; Terauchi, Takashi; Inoue, Tomio

    2014-01-01

    Objective(s): The aim of this study was to analyze detection rates and effectiveness of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) cancer screening program for prostate cancer in Japan, which is defined as a cancer-screening program for subjects without known cancer. It contains FDG-PET aimed at detection of cancer at an early stage with or without additional screening tests such as prostate-specific antigen (PSA) and magnetic resonance imaging (MRI). Methods: A total of 92,255 asymptomatic men underwent the FDG-PET cancer screening program. Of these, 504 cases with findings of possible prostate cancer in any screening method were analyzed. Results: Of the 504 cases, 165 were verified as having prostate cancer. Of these, only 61 cases were detected by FDG-PET, which result in 37.0% relative sensitivity and 32.8% positive predictive value (PPV). The sensitivity of PET/computed tomography (CT) scanner was higher than that of dedicated PET (44.0% vs. 20.4%). However, the sensitivity of FDG-PET was lower than that of PSA and pelvic MRI. FDG-PET did not contribute to improving the sensitivity and PPV when performed as combined screening. Conclusion: PSA should be included in FDG-PET cancer screening programs to screen for prostate cancer.

  6. Detection of Diffuse Infiltrative Primary Hepatic Lymphoma on FDG PET-CT: Hallmarks of Hepatic Superscan

    PubMed Central

    Mahajan, Sonia; Kalra, Shefali; Chawla, Madhavi; Dougall, Pankaj

    2016-01-01

    Primary hepatic lymphoma (PHL) is an extremely rare entity with scarce information in evidence-based literature. Few case reports have described the role of 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) in the diagnosing and staging of PHL. We report the case of a 78-year-old man with PHL who initially presented with weight loss and nonspecific fatigue. FDG PET-CT proved to be a beneficial tool in arriving at the diagnosis of this patient with nonspecific clinical presentation and also in the staging of PHL. Physiological uptake of FDG in the liver can be a potential cause of misinterpretation in such cases. Hence, knowing the imaging hallmarks can increase the accuracy in PET image interpretation. PMID:27134567

  7. Detection of Diffuse Infiltrative Primary Hepatic Lymphoma on FDG PET-CT: Hallmarks of Hepatic Superscan.

    PubMed

    Mahajan, Sonia; Kalra, Shefali; Chawla, Madhavi; Dougall, Pankaj

    2016-01-01

    Primary hepatic lymphoma (PHL) is an extremely rare entity with scarce information in evidence-based literature. Few case reports have described the role of 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) in the diagnosing and staging of PHL. We report the case of a 78-year-old man with PHL who initially presented with weight loss and nonspecific fatigue. FDG PET-CT proved to be a beneficial tool in arriving at the diagnosis of this patient with nonspecific clinical presentation and also in the staging of PHL. Physiological uptake of FDG in the liver can be a potential cause of misinterpretation in such cases. Hence, knowing the imaging hallmarks can increase the accuracy in PET image interpretation. PMID:27134567

  8. FDG-PET Quantification of Lung Inflammation with Image-Derived Blood Input Function in Mice

    PubMed Central

    Locke, Landon W.; Williams, Mark B.; Fairchild, Karen D.; Zhong, Min; Kundu, Bijoy K.; Berr, Stuart S.

    2011-01-01

    Dynamic FDG-PET imaging was used to study inflammation in lungs of mice following administration of a virulent strain of Klebsiella (K.) pneumoniae. Net whole-lung FDG influx constant (Ki) was determined in a compartment model using an image-derived blood input function. Methods. K. pneumoniae (~3 x 105 CFU) was intratracheally administered to six mice with 6 other mice serving as controls. Dynamic FDG-PET and X-Ray CT scans were acquired 24 hr after K. pneumoniae administration. The experimental lung time activity curves were fitted to a 3-compartment FDG model to obtain Ki. Following imaging, lungs were excised and immunohistochemistry analysis was done to assess the relative presence of neutrophils and macrophages. Results. Mean Ki for control and K. pneumoniae infected mice were (5.1 ± 1.2) ×10−3 versus (11.4 ± 2.0) ×10−3 min−1, respectively, revealing a 2.24 fold significant increase (P = 0.0003) in the rate of FDG uptake in the infected lung. Immunohistochemistry revealed that cellular lung infiltrate was almost exclusively neutrophils. Parametric Ki maps by Patlak analysis revealed heterogeneous inflammatory foci within infected lungs. Conclusion. The kinetics of FDG uptake in the lungs of mice can be noninvasively quantified by PET with a 3-compartment model approach based on an image-derived input function. PMID:22187641

  9. 18F-FDG PET/CT in multicentric Castleman disease: a case report

    PubMed Central

    Zhang, Jiexin; Yang, Lu

    2016-01-01

    Castleman disease (CD) is a chronic lymphoproliferative disorder characterized by unexplained enlarged lymph nodes. According to lymph nodes distribution it contains two types of single-centric and multicentric (more than one site) disease. Multicentric Castleman disease (MCD) is rare, and shows unspecific manifestation with high misdiagnosis rate. Here we reported a case of MCD in a 43-year-old male. 18F-FDG PET/CT imaging demonstrated higher FDG uptake in multiple lymph nodes and slightly FDG uptake in spleen and bone marrow. Right inguinal Lymph node biopsy was taken and the results confirmed CD. PMID:26904580

  10. Focal Inflammatory Myositis on 18F-FDG PET/CT.

    PubMed

    Bennett, Olivia; Ravi Kumar, Aravind S; Agnew, Julie

    2016-06-01

    Focal myositis is a rare benign inflammatory pseudotumor that can mimic malignancy, clinically and on imaging. A 34-year-old man presented with a 3-week history of sudden-onset, nontender, left upper neck mass that was nonresolving with antibiotics. Anatomical imaging was concerning for a sarcoma of the sternocleidomastoid muscle with possible regional nodal metastases and surrounding inflammatory change. F-FDG PET/CT showed marked FDG uptake extending around the anterior border of the sternocleidomastoid muscle with no FDG-avid local nodal disease. Core biopsy of the sternocleidomastoid muscle and adjacent node revealed inflammatory changes. A diagnosis of focal inflammatory myositis was made. PMID:27055132

  11. Accuracy of [18F]FDG PET/MRI for the Detection of Liver Metastases

    PubMed Central

    Beiderwellen, Karsten; Geraldo, Llanos; Ruhlmann, Verena; Heusch, Philipp; Gomez, Benedikt; Nensa, Felix; Umutlu, Lale; Lauenstein, Thomas C.

    2015-01-01

    Background The aim of this study was to compare the diagnostic accuracy of [18F]FDG-PET/MRI with PET/CT for the detection of liver metastases. Methods 32 patients with solid malignancies underwent [18F]FDG-PET/CT and subsequent PET/MRI of the liver. Two readers assessed both datasets regarding lesion characterization (benign, indeterminate, malignant), conspicuity and diagnostic confidence. An imaging follow-up (mean interval: 185±92 days) and/-or histopathological specimen served as standards of reference. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for both modalities. Accuracy was determined by calculating the area under the receiver operating characteristic (ROC) curve. Values of conspicuity and diagnostic confidence were compared using Wilcoxon-signed-rank test. Results The standard of reference revealed 113 liver lesions in 26 patients (malignant: n = 45; benign: n = 68). For PET/MRI a higher accuracy (PET/CT: 82.4%; PET/MRI: 96.1%; p<0.001) as well as sensitivity (67.8% vs. 92.2%, p<0.01) and NPV (82.0% vs. 95.1%, p<0.05) were observed. PET/MRI offered higher lesion conspicuity (PET/CT: 2.0±1.1 [median: 2; range 0–3]; PET/MRI: 2.8±0.5 [median: 3; range 0–3]; p<0.001) and diagnostic confidence (PET/CT: 2.0±0.8 [median: 2; range: 1–3]; PET/MRI 2.6±0.6 [median: 3; range: 1–3]; p<0.001). Furthermore, PET/MRI enabled the detection of additional PET-negative metastases (reader 1: 10; reader 2: 12). Conclusions PET/MRI offers higher diagnostic accuracy compared to PET/CT for the detection of liver metastases. PMID:26335246

  12. Estimation of radiation dose to patients from 18FDG whole body PET/CT investigations using dynamic PET scan protocol

    PubMed Central

    Kaushik, Aruna; Jaimini, Abhinav; Tripathi, Madhavi; D’Souza, Maria; Sharma, Rajnish; Mondal, Anupam; Mishra, Anil K.; Dwarakanath, Bilikere S.

    2015-01-01

    Background & objectives: There is a growing concern over the radiation exposure of patients from undergoing 18FDG PET/CT (18F-fluorodeoxyglucose positron emission tomography/computed tomography) whole body investigations. The aim of the present study was to study the kinetics of 18FDG distributions and estimate the radiation dose received by patients undergoing 18FDG whole body PET/CT investigations. Methods: Dynamic PET scans in different regions of the body were performed in 49 patients so as to measure percentage uptake of 18FDG in brain, liver, spleen, adrenals, kidneys and stomach. The residence time in these organs was calculated and radiation dose was estimated using OLINDA software. The radiation dose from the CT component was computed using the software CT-Expo and measured using computed tomography dose index (CTDI) phantom and ionization chamber. As per the clinical protocol, the patients were refrained from eating and drinking for a minimum period of 4 h prior to the study. Results: The estimated residence time in males was 0.196 h (brain), 0.09 h (liver), 0.007 h (spleen), 0.0006 h (adrenals), 0.013 h (kidneys) and 0.005 h (stomach) whereas it was 0.189 h (brain), 0.11 h (liver), 0.01 h (spleen), 0.0007 h (adrenals), 0.02 h (kidneys) and 0.004 h (stomach) in females. The effective dose was found to be 0.020 mSv/MBq in males and 0.025 mSv/MBq in females from internally administered 18FDG and 6.8 mSv in males and 7.9 mSv in females from the CT component. For an administered activity of 370 MBq of 18FDG, the effective dose from PET/CT investigations was estimated to be 14.2 mSv in males and 17.2 mSv in females. Interpretation & conclusions: The present results did not demonstrate significant difference in the kinetics of 18FDG distribution in male and female patients. The estimated PET/CT doses were found to be higher than many other conventional diagnostic radiology examinations suggesting that all efforts should be made to clinically justify and

  13. Regional, kinetic [18F]FDG PET imaging of a unilateral Parkinsonian animal model

    PubMed Central

    Silva, Matthew D; Glaus, Charles; Hesterman, Jacob Y; Hoppin, Jack; Puppa, Geraldine Hill della; Kazules, Timothy; Orcutt, Kelly M; Germino, Mary; Immke, David; Miller, Silke

    2013-01-01

    Positron emission tomography (PET) imaging with the glucose analog 2-deoxy-2-[18F]fluoro-D-glucose ([18F] FDG) has demonstrated clinical utility for the monitoring of brain glucose metabolism alteration in progressive neurodegenerative diseases. We examined dynamic [18F]FDG PET imaging and kinetic modeling of atlas-based regions to evaluate regional changes in the cerebral metabolic rate of glucose in the widely-used 6-hydroxydopamine (6-OHDA) rat model of Parkinson’s disease. Following a bolus injection of 18.5 ± 1 MBq [18F]FDG and a 60-minute PET scan, image-derived input functions from the vena cava and left ventricle were used with three models, including Patlak graphical analysis, to estimate the influx constant and the metabolic rate in ten brain regions. We observed statistically significant changes in [18F]FDG uptake ipsilateral to the 6-OHDA injection in the basal ganglia, olfactory bulb, and amygdala regions; and these changes are of biological relevance to the disease. These experiments provide further validation for the use of [18F]FDG PET imaging in this model for drug discovery and development. PMID:23526185

  14. Repeatability of the Maximum Standard Uptake Value (SUVmax) in FDG PET

    PubMed Central

    Lindholm, Henry; Staaf, Johan; Jacobsson, Hans; Brolin, Fredrik; Hatherly, Robert; Sânchez-Crespo, Alejandro

    2014-01-01

    Objective: SUVmax is often calculated at FDG PET examinations in systematic studies as well as at clinical examinations. Since SUVmax represents a very small portion of a lesion it may be questioned how statistically reliable the figure is. This was studied by assessing the repeatability of SUVmax between two FDG acquisitions acquired immediately upon each other in patients with chest lesions. Methods: In 100 clinical patients with a known chest lesion, two identical 3 min PET registrations (PET1 and PET2, respectively) were initiated within 224±31 sec of each other. The difference in SUVmax between the lesion for the two PET scans (ΔSUVmax) was calculated and the uncertainty expressed as the coefficient of variation, CV (%). The correlation between ΔSUVmax and the lowest SUVmax from PET1 or PET2, the approximate metabolic lesion volume, the time from FDG injection to PET1 and the time between PET1 and PET2, respectively, was also assessed. Results: In 56 patients SUVmax increased at the second acquisition and in 44 patients it decreased. Mean of SUVmax was 7.8±6.1 and 7.8±6.2 for PET1 and PET2, respectively. The mean percentage difference was 0.9±7.8. The difference was not significant (p=0.20). CV gave an uncertainty of 4.3% between the two measurements which is a strong indicator of equivalence. There was no correlation between ΔSUVmax and any of the assessed four parameters. The difference between the acquisitions, 0.9%, was much lower compared to the 3 previous published similar, but more restricted studies where the difference was 2.5-8.2%. Conclusion: From camera and computational perspectives, SUVmax is a stable parameter Conflict of interest:None declared. PMID:24653930

  15. 18F-FDG PET/CT Findings in a Patient With a Proliferating Trichilemmal Cyst.

    PubMed

    Leyendecker, Pierre; de Cambourg, Ghislaine; Mahé, Antoine; Imperiale, Alessio; Blondet, Cyrille

    2015-07-01

    Proliferating trichilemmal cyst is considered as a rare tumor that originates in the outer root sheath of hair follicle. Metastatic potential has not been yet fully established. Moreover, histological analysis does not allow precise malignancy prediction. Proliferating trichilemmal cyst glucose metabolism behavior was never previously described. Herein, we report the case of a 62-year-old patient with a left shoulder proliferating trichilemmal cyst showing an intense uptake of ¹⁸F-FDG on PET/CT examination. ¹⁸F-FDG PET/CT could be proposed to optimize diagnostic strategy of patients with proliferating trichilemmal cysts. PMID:25706794

  16. Present and future roles of FDG-PET/CT imaging in the management of lung cancer.

    PubMed

    Kitajima, Kazuhiro; Doi, Hiroshi; Kanda, Tomonori; Yamane, Tomohiko; Tsujikawa, Tetsuya; Kaida, Hayato; Tamaki, Yukihisa; Kuribayashi, Kozo

    2016-06-01

    Integrated positron emission tomography/computed tomography (PET/CT) using 2-[(18)F]fluoro-2-deoxy-D-glucose ((18)F-FDG) has emerged as a powerful tool for combined metabolic and anatomic evaluation in clinical oncologic imaging. This review discusses the utility of (18)F-FDG PET/CT as a tool for managing patients with lung cancer. We discuss different patient management stages, including diagnosis, initial staging, therapy planning, early treatment response assessment, re-staging, and prognosis. PMID:27121156

  17. Extraosseous Osteosarcoma of the Liver Demonstrated on 18F-FDG PET/CT Imaging.

    PubMed

    Jiang, Lei; Luan, Lijuan; Yun, Hong; Hou, Yingyong; Shi, Hongcheng

    2016-08-01

    A 66-year-old woman presented with abdominal pain for 1 month. Ultrasonography displayed multiple hepatic masses that were thought as metastases. FDG PET/CT was performed to assess the nature of these masses and to search primary malignancy. The images showed elevated FDG activity in the partially calcified hypodense lesions in the liver without abnormality elsewhere. The lesions were subsequently confirmed as primary extraosseous osteosarcoma in the liver. The patient received liver transplantation. Six months later, her CA-125 was significantly increased. The follow-up PET/CT scan demonstrated the widespread metastases. PMID:27055145

  18. 18F-FDG PET/CT Imaging of Burkitt Lymphoma Presenting With Unusual Muscle Involvement.

    PubMed

    Dirlik Serim, Burcu; Gurleyen Eren, Tuba; Oz Puyan, Fulya; Durmus Altun, Gülay

    2016-08-01

    Extranodal involvement is more common with Burkitt lymphoma (BL) than other subtypes of non-Hodgkin lymphoma in childhood. According to our knowledge, there are rare cases in the literature about muscle involvement of BL, and its F-FDG PET/CT findings were not well defined. We report a 6-year-old girl with a histopathologic diagnosis of BL and referred for staging with PET/CT. FDG-avid abdominal lymph nodes and diffuse involvements of right quadriceps muscle were demonstrated. PMID:27124681

  19. FDG PET/CT Findings of Recurrent Respiratory Papillomatosis With Malignant Degeneration in the Lung.

    PubMed

    Tatci, Ebru; Gokcek, Atila; Unsal, Ebru; Cimen, Filiz; Demirag, Funda; Yazici, Senem; Ozmen, Ozlem

    2015-10-01

    Recurrent respiratory papillomatosis is a rare benign disease caused by HPV-6 or HPV-11. The tumors may rarely undergo malignant degeneration. We performed FDG PET/CT in a patient experiencing recurrent respiratory papillomatosis who had pulmonary involvement. Although squamous cell carcinoma was detected in one of the pulmonary masses, squamous metaplasia with dysplasia were detected in the other one. Intensity modulated radiation therapy was performed to treat the malignancy. Second FDG PET/CT was performed 15 months after radiotherapy. PMID:26204210

  20. Value of FDG PET/CT in staging of oral cancer: four simultaneous primary malignancies.

    PubMed

    Linz, Christian; Müller-Richter, Urs D A; Kircher, Stefan; Lapa, Constantin; Bluemel, Christina

    2015-05-01

    Patients with squamous cell cancer (SCC) of the head and neck are at increased risk for second primary malignancies (SPMs). We report on a 53-year-old patient with primary diagnosis of SCC in the anterior floor of the mouth. Panendoscopy suspected an SPM of the right vocal cord. FDG PET/CT, as a whole-body imaging method, confirmed this suspicion and raised concern for further SPM of both esophagus and colon. All malignancies were confirmed by biopsy. Subsequently, the patient underwent radiochemotherapy. In summary, FDG PET/CT revealed unexpected multiple SPMs, prevented unnecessary resection of the oral SCC, and enabled individualized therapeutic management. PMID:25742223

  1. Hypoxia is important in F-18 FDG accumulation in thecoma-fibroma tumors on F-18 FDG PET/CT scans

    PubMed Central

    SEINO, HIROKO; ONO, SHUICHI; MIURA, HIROYUKI; MOROHASHI, SATOKO; WU, YUNYAN; TSUSHIMA, FUMIYASU; TAKAI, YOSHIHIRO; KIJIMA, HIROSHI

    2016-01-01

    Several studies have noted benign thecoma-fibroma tumors with positive F-18 fluorodeoxyglucose (FDG) accumulation mimicking malignant ovarian tumors following F-18 FDG positron emission tomography (PET). The present study analyzed four cases with false-positive F-18 FDG PET/computed tomography (CT) diagnoses of thecoma-fibroma tumors as malignant tumors due to F-18 FDG accumulation, compared with eight cases of FDG-positive ovarian cancers and two cases of FDG-negative fibromas. Hypoxia inducible factor (HIF)-1α expression was examined in the six thecoma-fibroma tumors using reverse transcription-polymerase chain reaction (RT-PCR). The four F-18 FDG-positive cases exhibited higher cellularity, maximum standard uptake and signal intensity on T2-weighted imaging, and gadolinium (Gd) enhancement using magnetic resonance imaging than the two FDG-negative fibroma cases. In the F-18 FDG-positive thecoma-fibroma group, Ki-67 expression was low and LAT1 expression was not identified, ruling out the diagnosis and potential for malignancy. However, considerable glucose transporter 1, HIF-1α, and vascular endothelial growth factor expression was observed. HIF-1α expression was elevated in all four false-positive cases by RT-PCR. From these results, it was hypothesized that hypoxia due to elevated cellularity may stimulate HIF-1α expression and be associated with F-18 FDG accumulation in F-18-positive thecoma-fibroma tumors. PMID:27035330

  2. Tumor Response and Survival Predicted by Post-Therapy FDG-PET/CT in Anal Cancer

    SciTech Connect

    Schwarz, Julie K.; Siegel, Barry A.; Dehdashti, Farrokh; Myerson, Robert J.; Fleshman, James W.; Grigsby, Perry W.

    2008-05-01

    Purpose: To evaluate the response to therapy for anal carcinoma using post-therapy imaging with positron emission tomography (PET)/computed tomography and F-18 fluorodeoxyglucose (FDG) and to compare the metabolic response with patient outcome. Patients and Methods: This was a prospective cohort study of 53 consecutive patients with anal cancer. All patients underwent pre- and post-treatment whole-body FDG-PET/computed tomography. Patients had been treated with external beam radiotherapy and concurrent chemotherapy. Whole-body FDG-PET was performed 0.9-5.4 months (mean, 2.1) after therapy completion. Results: The post-therapy PET scan did not show any abnormal FDG uptake (complete metabolic response) in 44 patients. Persistent abnormal FDG uptake (partial metabolic response) was found in the anal tumor in 9 patients. The 2-year cause-specific survival rate was 94% for patients with a complete vs. 39% for patients with a partial metabolic response in the anal tumor (p = 0.0008). The 2-year progression-free survival rate was 95% for patients with a complete vs. 22% for patients with a partial metabolic response in the anal tumor (p < 0.0001). A Cox proportional hazards model of survival outcome indicated that a complete metabolic response was the most significant predictor of progression-free survival in our patient population (p = 0.0003). Conclusions: A partial metabolic response in the anal tumor as determined by post-therapy FDG-PET is predictive of significantly decreased progression-free and cause-specific survival after chemoradiotherapy for anal cancer.

  3. MicroPET II: design, development and initial performance of an improved microPET scanner for small-animal imaging

    NASA Astrophysics Data System (ADS)

    Tai, Yuan-Chuan; Chatziioannou, Arion F.; Yang, Yongfeng; Silverman, Robert W.; Meadors, Ken; Siegel, Stefan; Newport, Danny F.; Stickel, Jennifer R.; Cherry, Simon R.

    2003-06-01

    MicroPET II is a second-generation animal PET scanner designed for high-resolution imaging of small laboratory rodents. The system consists of 90 scintillation detector modules arranged in three contiguous axial rings with a ring diameter of 16.0 cm and an axial length of 4.9 cm. Each detector module consists of a 14 × 14 array of lutetium oxyorthosilicate (LSO) crystals coupled to a multi-channel photomultiplier tube (MC-PMT) through a coherent optical fibre bundle. Each LSO crystal element measures 0.975 mm × 0.975 mm in cross section by 12.5 mm in length. A barium sulphate reflector material was used between LSO elements leading to a detector pitch of 1.15 mm in both axial and transverse directions. Fused optical fibre bundles were made from 90 µm diameter glass fibres with a numerical aperture of 0.56. Interstitial extramural absorber was added between the fibres to reduce optical cross talk. A charge-division readout circuit was implemented on printed circuit boards to decode the 196 crystals in each array from the outputs of the 64 anode signals of the MC-PMT. Electronics from Concorde Microsystems Inc. (Knoxville, TN) were used for signal amplification, digitization, event qualification, coincidence processing and data capture. Coincidence data were passed to a host PC that recorded events in list mode. Following acquisition, data were sorted into sinograms and reconstructed using Fourier rebinning and filtered backprojection algorithms. Basic evaluation of the system has been completed. The absolute sensitivity of the microPET II scanner was 2.26% at the centre of the field of view (CFOV) for an energy window of 250-750 keV and a timing window of 10 ns. The intrinsic spatial resolution of the detectors in the system averaged 1.21 mm full width at half maximum (FWHM) when measured with a 22Na point source 0.5 mm in diameter. Reconstructed image resolution ranged from 0.83 mm FWHM at the CFOV to 1.47 mm FWHM in the radial direction, 1.17 mm FWHM in the

  4. MicroPET II: design, development and initial performance of an improved microPET scanner for small-animal imaging.

    PubMed

    Tai, Yuan-Chuan; Chatziioannou, Arion F; Yang, Yongfeng; Silverman, Robert W; Meadors, Ken; Siegel, Stefan; Newport, Danny F; Stickel, Jennifer R; Cherry, Simon R

    2003-06-01

    MicroPET II is a second-generation animal PET scanner designed for high-resolution imaging of small laboratory rodents. The system consists of 90 scintillation detector modules arranged in three contiguous axial rings with a ring diameter of 16.0 cm and an axial length of 4.9 cm. Each detector module consists of a 14 x 14 array of lutetium oxyorthosilicate (LSO) crystals coupled to a multi-channel photomultiplier tube (MC-PMT) through a coherent optical fibre bundle. Each LSO crystal element measures 0.975 mm x 0.975 mm in cross section by 12.5 mm in length. A barium sulphate reflector material was used between LSO elements leading to a detector pitch of 1.15 mm in both axial and transverse directions. Fused optical fibre bundles were made from 90 microm diameter glass fibres with a numerical aperture of 0.56. Interstitial extramural absorber was added between the fibres to reduce optical cross talk. A charge-division readout circuit was implemented on printed circuit boards to decode the 196 crystals in each array from the outputs of the 64 anode signals of the MC-PMT. Electronics from Concorde Microsystems Inc. (Knoxville, TN) were used for signal amplification, digitization, event qualification, coincidence processing and data capture. Coincidence data were passed to a host PC that recorded events in list mode. Following acquisition, data were sorted into sinograms and reconstructed using Fourier rebinning and filtered hackprojection algorithms. Basic evaluation of the system has been completed. The absolute sensitivity of the microPET II scanner was 2.26% at the centre of the field of view (CFOV) for an energy window of 250-750 keV and a timing window of 10 ns. The intrinsic spatial resolution of the detectors in the system averaged 1.21 mm full width at half maximum (FWHM) when measured with a 22Na point source 0.5 mm in diameter. Reconstructed image resolution ranged from 0.83 mm FWHM at the CFOV to 1.47 mm FWHM in the radial direction, 1.17 mm FWHM in the

  5. Metformin and cancer: Technical and clinical implications for FDG-PET imaging

    PubMed Central

    Capitanio, Selene; Marini, Cecilia; Sambuceti, Gianmario; Morbelli, Silvia

    2015-01-01

    Metformin is the most widely used hypoglycemic agent. Besides its conventional indications, increasing evidence demonstrate a potential efficacy of this biguanide as an anticancer drug. Possible mechanisms of actions seem to be independent from its hypoglycemic effect and seem to involve the interference with key pathways in cellular proliferation and glycolysis. To date, many clinical trials implying the use of metformin in cancer treatment are on-going. The increasing use of 18F-2-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) in cancer evaluation raises a number of questions about the possible interference of the biguanide on FDG distribution. In particular, the interferences exerted by metformin on AMP-activated protein kinase pathway (the cellular energy sensor), on insulin levels and on Hexokinase could potentially have repercussion on glucose handling and thus on FDG distribution. A better comprehension of the impact of metformin on FDG uptake is needed in order to optimize the use of PET in this setting. This evaluation would be useful to ameliorate scans interpretation in diabetic patients under chronic metformin treatment and to critically interpret images in the context of clinical trials. Furthermore, collecting prospective data in this setting would help to verify whether FDG-PET could be a valid tool to appreciate the anticancer effect of this new therapeutic approach. PMID:25825634

  6. Metformin and cancer: Technical and clinical implications for FDG-PET imaging.

    PubMed

    Capitanio, Selene; Marini, Cecilia; Sambuceti, Gianmario; Morbelli, Silvia

    2015-03-28

    Metformin is the most widely used hypoglycemic agent. Besides its conventional indications, increasing evidence demonstrate a potential efficacy of this biguanide as an anticancer drug. Possible mechanisms of actions seem to be independent from its hypoglycemic effect and seem to involve the interference with key pathways in cellular proliferation and glycolysis. To date, many clinical trials implying the use of metformin in cancer treatment are on-going. The increasing use of (18)F-2-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) in cancer evaluation raises a number of questions about the possible interference of the biguanide on FDG distribution. In particular, the interferences exerted by metformin on AMP-activated protein kinase pathway (the cellular energy sensor), on insulin levels and on Hexokinase could potentially have repercussion on glucose handling and thus on FDG distribution. A better comprehension of the impact of metformin on FDG uptake is needed in order to optimize the use of PET in this setting. This evaluation would be useful to ameliorate scans interpretation in diabetic patients under chronic metformin treatment and to critically interpret images in the context of clinical trials. Furthermore, collecting prospective data in this setting would help to verify whether FDG-PET could be a valid tool to appreciate the anticancer effect of this new therapeutic approach. PMID:25825634

  7. 18F-FDG PET/CT for the assessment of gastrointestinal GVHD: results of a pilot study.

    PubMed

    Bodet-Milin, C; Lacombe, M; Malard, F; Lestang, E; Cahu, X; Chevallier, P; Guillaume, T; Delaunay, J; Brissot, E; Moreau, P; Kraeber-Bodere, F; Mohty, M

    2014-01-01

    This prospective pilot study aimed to evaluate the predictive value of (18)F-FDG PET/CT for early diagnosis of acute gastrointestinal GVHD (GI-GVHD). In all, 42 consecutive patients who received allo-SCT were included. (18)F-FDG PET/CT was systematically performed at a median of 28 (range, 24-38) days after allo-SCT. (18)F-FDG PET/CT data review was positive in 15 cases (36%) (9 true positive (TP) cases and 6 false positive (FP) cases) and negative in 27 cases (64%; 26 true negative (TN) cases and 1 false negative (FN) case) at visual analysis. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of (18)F-FDG PET/CT for the diagnosis of acute GI-GVHD were, respectively, 81%, 90%, 60%, 96% and 83%. There were no significant differences of SUVmax values between grade 1-2 GI-GVHD and severe grade 3-4 GI-GVHD. Overall, these preliminary findings suggested that the inflammatory activity of the gastrointestinal tract associated with acute GI-GVHD could be assessed by (18)F-FDG PET/CT suggesting that noninvasive (18)F-FDG PET/CT could become a valuable examination to be performed shortly before endoscopy to map acute GI-GVHD lesions, guide the biopsy sites and choose the appropriate endoscopic procedure, especially in those asymptomatic patients with a positive (18)F-FDG PET/CT. PMID:24076550

  8. Interim FDG-PET Scan in Hodgkin's Lymphoma: Hopes and Caveats

    PubMed Central

    André, M.; Vander Borght, T.; Bosly, A.

    2011-01-01

    FDG-PET has recently emerged as an important tool for the management of Hodgkins lymphoma. Although its use for initial staging and response evaluation at the end of treatment is well established, the place of interim PET for response assessment and subsequent treatment tailoring is still quite controversial. The use of interim PET after a few cycles of chemotherapy may allow treatment reduction for good responders, leading to lesser treatment toxicities as well as early treatment adaptation for bad responders with a potential higher chance for cure. Interpretation of interim PET is a rapidly moving field. Actually, visual interpretation is preferred over quantitative interpretation in this situation. The notion of minimal residual uptake emerged for faint persisting FDG uptake, but has evolved during the recent years. Guidelines using mediastinum and liver as references have been proposed at the expert meeting in Deauville 2009. Actually, several trials are ongoing both for localised and advanced disease to evaluate the FDG-PET potential for early treatment monitoring and tailoring. Until the results of these prospective randomized trials become available, treatment changes according to the interim PET results should remain inappropriate and limited to well-conducted clinical trials. PMID:21234093

  9. Primary Neuroendocrine Carcinoma of the Kidney on FDG PET/CT.

    PubMed

    Shi, Ximin; Li, Fang; Luo, Yaping; Huo, Li

    2016-09-01

    A 28-year-old woman presented gradually worsening intermittent right groin pain for 10 months. FDG PET/CT was performed to evaluate the suspected renal malignancy. The images demonstrated a large hypermetabolic tumor occupying the entire right kidney. Pathological examination demonstrated a primary neuroendocrine carcinoma of the kidney. PMID:27504808

  10. F18-FDG-PET for recurrent differentiated thyroid cancer: a systematic meta-analysis

    PubMed Central

    Haslerud, Torjan; Brauckhoff, Katrin; Reisæter, Lars; Küfner Lein, Regina; Heinecke, Achim; Varhaug, Jan Erik

    2015-01-01

    Background Positron emission tomography (PET) with fluor-18-deoxy-glucose (FDG) is widely used for diagnosing recurrent or metastatic disease in patients with differentiated thyroid cancer (DTC). Purpose To assess the diagnostic accuracy of FDG-PET for DTC in patients after ablative therapy. Material and Methods A systematic search was conducted in Medline/PubMed, EMBASE, Cochrane Library, Web of Science, and Open Grey looking for all English-language original articles on the performance of FDG-PET in series of at least 20 patients with DTC having undergone ablative therapy including total thyroidectomy. Diagnostic performance measures were pooled using Reitsma’s bivariate model. Results Thirty-four publications between 1996 and 2014 met the inclusion criteria. Pooled sensitivity and specificity were 79.4% (95% confidence interval [CI], 73.9–84.1) and 79.4% (95% CI, 71.2–85.4), respectively, with an area under the curve of 0.858. Conclusion F18-FDG-PET is a useful method for detecting recurrent DTC in patients having undergone ablative therapy. PMID:26163534

  11. 18F-FDG PET/CT Findings in Acute Epstein-Barr Virus Infection Mimicking Malignant Lymphoma

    PubMed Central

    Ørbæk, Mathilde; Graff, Jesper; Markova, Elena; Kronborg, Gitte; Lebech, Anne-Mette

    2016-01-01

    We present a case demonstrating the diagnostic work-up and follow-up of a patient with acute Epstein-Barr virus (EBV) infection in which the clinical picture and imaging on 18F-FDG PET/CT mimicked malignant lymphoma. Follow-up 18F-FDG PET/CT scan in the patient performed 7 weeks after the abnormal scan revealed complete resolution of the metabolically active disease in the neck, axillas, lung hili, and spleen. This case highlights inflammation as one of the most well established false positives when interpreting 18F-FDG PET/CT scans. PMID:27187482

  12. (18)F-FDG PET/CT Findings in Acute Epstein-Barr Virus Infection Mimicking Malignant Lymphoma.

    PubMed

    Ørbæk, Mathilde; Graff, Jesper; Markova, Elena; Kronborg, Gitte; Lebech, Anne-Mette

    2016-01-01

    We present a case demonstrating the diagnostic work-up and follow-up of a patient with acute Epstein-Barr virus (EBV) infection in which the clinical picture and imaging on (18)F-FDG PET/CT mimicked malignant lymphoma. Follow-up (18)F-FDG PET/CT scan in the patient performed 7 weeks after the abnormal scan revealed complete resolution of the metabolically active disease in the neck, axillas, lung hili, and spleen. This case highlights inflammation as one of the most well established false positives when interpreting (18)F-FDG PET/CT scans. PMID:27187482

  13. Lymphadenopathy by Scrub Typhus Mimicking Metastasis on FDG PET/CT in a Patient with a History of Breast Cancer.

    PubMed

    Lee, Jeong Won; Lee, Sang Mi; Lee, Kyu Taek; Kim, Sung Young; Han, Sun Wook; Kim, Shin Young

    2015-06-01

    We report the case of a 60-year-old woman with left-sided breast cancer who showed lymphadenopathy mimicking metastatic lesions. She underwent surveillance (18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) after treatment. PET/CT demonstrated multiple lymphadenopathies with increased FDG uptake, most notably in the right axilla. She had an eschar on the right axillary area, and her serologic test was positive for anti-Orientia tsutsugamushi IgM antibody. Ten months after the treatment, follow-up FDG PET/CT and ultrasonography showed improvement in generalized lymphadenopathy. PMID:26082810

  14. 18F-FDG PET of the hands with a dedicated high-resolution PEM system (arthro-PET): correlation with PET/CT, radiography and clinical parameters

    PubMed Central

    Mhlanga, Joyce C.; Carrino, John A.; Lodge, Martin; Wang, Hao

    2015-01-01

    Purpose The aim of this study was to prospectively determine the feasibility and compare the novel use of a positron emission mammography (PEM) scanner with standard PET/CT for evaluating hand osteoarthritis (OA) with 18F-FDG. Methods Institutional review board approval and written informed consent were obtained for this HIPAA-compliant prospective study in which 14 adults referred for oncological 18F-FDG PET/CT underwent dedicated hand PET/CT followed by arthro-PET using the PEM device. Hand radiographs were obtained and scored for the presence and severity of OA. Summed qualitative and quantitative joint glycolytic scores for each modality were compared with the findings on plain radiography and clinical features. Results Eight patients with clinical and/or radiographic evidence of OA comprised the OA group (mean age 73±7.7 years). Six patients served as the control group (53.7±9.3 years). Arthro-PET quantitative and qualitative joint glycolytic scores were highly correlated with PET/CT findings in the OA patients (r=0.86. p =0.007; r=0.94, p=0.001). Qualitative arthro-PET and PET/CT joint scores were significantly higher in the OA patients than in controls (38.7±6.6 vs. 32.2±0.4, p=0.02; 37.5±5.4 vs. 32.2±0.4, p=0.03, respectively). Quantitative arthro-PET and PET/CT maximum SUV-lean joint scores were higher in the OA patients, although they did not reach statistical significance (20.8±4.2 vs. 18±1.8, p= 0.13; 22.8±5.38 vs. 20.1±1.54, p=0.21). By definition, OA patients had higher radiographic joint scores than controls (30.9±31.3 vs. 0, p=0.03). Conclusion Hand imaging using a small field of view PEM system (arthro-PET) with FDG is feasible, performing comparably to PET/CT in assessing metabolic joint activity. Arthro-PET and PET/CT showed higher joint FDG uptake in OA. Further exploration of arthro-PET in arthritis management is warranted. PMID:25134669

  15. Natural history of atherosclerotic disease progression as assessed by (18)F-FDG PET/CT.

    PubMed

    Hetterich, Holger; Rominger, Axel; Walter, Lisa; Habs, Maximilian; Volpers, Sarah; Hacker, Marcus; Reiser, Maximilian F; Bartenstein, Peter; Saam, Tobias

    2016-01-01

    The aim of this study was to assess the impact of cardiovascular risk factors and plaque inflammation on the progression of atherosclerosis as assessed by positron emission tomography/computed tomography (PET/CT) imaging with (18)F-radiolabled fluorodeoxyglucose ((18)F-FDG). This study was designed as a retrospective cohort study. Patients who received a (18)F-FDG PET/CT scan and follow-up scan 9-24 months later without systemic inflammation or steroid medication were eligible for the study. (18)F-FDG PET/CT included a full diagnostic contrast enhanced CT scan. Cardiovascular risk factors and medication were documented. Calcified plaque volume, lumen area and (18)F-FDG uptake, quantified by the target-to-background ratio (TBR), were measured in the carotid arteries, aorta and iliac arteries. Influence of cardiovascular risk factors and vessel wall inflammation on atherosclerotic disease progression was analyzed. Ninety-four patients underwent baseline and follow-up whole body (18)F-FDG PET/CT (mean follow-up time 14.5 ± 3.5 months). Annualized calcified plaque volume increased by 15.4 % (p < 0.0001), carotid and aortic lumen area decreased by 10.5 % (p < 0.0001) and 1.7 % (p = 0.045). There was no significant difference in (18)F-FDG uptake at baseline and follow-up (mean TBR 1.44 ± 0.18 vs. 1.42 ± 0.19, p = 0.18). Multiple linear regression analysis identified hypertension as an independent predictor for total, aortic and iliac calcified plaque volume progression (all p < 0.04). Carotid lumen reduction was predicted by hypercholesterolemia (p = 0.008) while aortic lumen reduction was associated with BMI and mean (18)F-FDG uptake (p ≤ 0.005). Furthermore we observed a dose response relationship between the number of cardiovascular risk factors and calcified plaque volume progression in the aorta (p = 0.03). Findings from this study provide data on the natural history of atherosclerotic disease burden in multiple vascular beds and emphasize the value of

  16. FDG-PET imaging in mild traumatic brain injury: a critical review

    PubMed Central

    Byrnes, Kimberly R.; Wilson, Colin M.; Brabazon, Fiona; von Leden, Ramona; Jurgens, Jennifer S.; Oakes, Terrence R.; Selwyn, Reed G.

    2013-01-01

    Traumatic brain injury (TBI) affects an estimated 1.7 million people in the United States and is a contributing factor to one third of all injury related deaths annually. According to the CDC, approximately 75% of all reported TBIs are concussions or considered mild in form, although the number of unreported mild TBIs (mTBI) and patients not seeking medical attention is unknown. Currently, classification of mTBI or concussion is a clinical assessment since diagnostic imaging is typically inconclusive due to subtle, obscure, or absent changes in anatomical or physiological parameters measured using standard magnetic resonance (MR) or computed tomography (CT) imaging protocols. Molecular imaging techniques that examine functional processes within the brain, such as measurement of glucose uptake and metabolism using [18F]fluorodeoxyglucose and positron emission tomography (FDG-PET), have the ability to detect changes after mTBI. Recent technological improvements in the resolution of PET systems, the integration of PET with magnetic resonance imaging (MRI), and the availability of normal healthy human databases and commercial image analysis software contribute to the growing use of molecular imaging in basic science research and advances in clinical imaging. This review will discuss the technological considerations and limitations of FDG-PET, including differentiation between glucose uptake and glucose metabolism and the significance of these measurements. In addition, the current state of FDG-PET imaging in assessing mTBI in clinical and preclinical research will be considered. Finally, this review will provide insight into potential critical data elements and recommended standardization to improve the application of FDG-PET to mTBI research and clinical practice. PMID:24409143

  17. FDG-PET imaging in mild traumatic brain injury: a critical review.

    PubMed

    Byrnes, Kimberly R; Wilson, Colin M; Brabazon, Fiona; von Leden, Ramona; Jurgens, Jennifer S; Oakes, Terrence R; Selwyn, Reed G

    2014-01-01

    Traumatic brain injury (TBI) affects an estimated 1.7 million people in the United States and is a contributing factor to one third of all injury related deaths annually. According to the CDC, approximately 75% of all reported TBIs are concussions or considered mild in form, although the number of unreported mild TBIs (mTBI) and patients not seeking medical attention is unknown. Currently, classification of mTBI or concussion is a clinical assessment since diagnostic imaging is typically inconclusive due to subtle, obscure, or absent changes in anatomical or physiological parameters measured using standard magnetic resonance (MR) or computed tomography (CT) imaging protocols. Molecular imaging techniques that examine functional processes within the brain, such as measurement of glucose uptake and metabolism using [(18)F]fluorodeoxyglucose and positron emission tomography (FDG-PET), have the ability to detect changes after mTBI. Recent technological improvements in the resolution of PET systems, the integration of PET with magnetic resonance imaging (MRI), and the availability of normal healthy human databases and commercial image analysis software contribute to the growing use of molecular imaging in basic science research and advances in clinical imaging. This review will discuss the technological considerations and limitations of FDG-PET, including differentiation between glucose uptake and glucose metabolism and the significance of these measurements. In addition, the current state of FDG-PET imaging in assessing mTBI in clinical and preclinical research will be considered. Finally, this review will provide insight into potential critical data elements and recommended standardization to improve the application of FDG-PET to mTBI research and clinical practice. PMID:24409143

  18. Detection of bladder metabolic artifacts in (18)F-FDG PET imaging.

    PubMed

    Roman-Jimenez, Geoffrey; Crevoisier, Renaud De; Leseur, Julie; Devillers, Anne; Ospina, Juan David; Simon, Antoine; Terve, Pierre; Acosta, Oscar

    2016-04-01

    Positron emission tomography using (18)F-fluorodeoxyglucose ((18)F-FDG-PET) is a widely used imaging modality in oncology. It enables significant functional information to be included in analyses of anatomical data provided by other image modalities. Although PET offers high sensitivity in detecting suspected malignant metabolism, (18)F-FDG uptake is not tumor-specific and can also be fixed in surrounding healthy tissue, which may consequently be mistaken as cancerous. PET analyses may be particularly hampered in pelvic-located cancers by the bladder׳s physiological uptake potentially obliterating the tumor uptake. In this paper, we propose a novel method for detecting (18)F-FDG bladder artifacts based on a multi-feature double-step classification approach. Using two manually defined seeds (tumor and bladder), the method consists of a semi-automated double-step clustering strategy that simultaneously takes into consideration standard uptake values (SUV) on PET, Hounsfield values on computed tomography (CT), and the distance to the seeds. This method was performed on 52 PET/CT images from patients treated for locally advanced cervical cancer. Manual delineations of the bladder on CT images were used in order to evaluate bladder uptake detection capability. Tumor preservation was evaluated using a manual segmentation of the tumor, with a threshold of 42% of the maximal uptake within the tumor. Robustness was assessed by randomly selecting different initial seeds. The classification averages were 0.94±0.09 for sensitivity, 0.98±0.01 specificity, and 0.98±0.01 accuracy. These results suggest that this method is able to detect most (18)F-FDG bladder metabolism artifacts while preserving tumor uptake, and could thus be used as a pre-processing step for further non-parasitized PET analyses. PMID:26897070

  19. FDG-PET as a predictive biomarker for therapy with everolimus in metastatic renal cell cancer

    PubMed Central

    Chen, James L; Appelbaum, Daniel E; Kocherginsky, Masha; Cowey, Charles L; Kimryn Rathmell, Wendy; McDermott, David F; Stadler, Walter M

    2013-01-01

    Abstract The mTOR (mammalian target of rapamycin) inhibitor, everolimus, affects tumor growth by targeting cellular metabolic proliferation pathways and delays renal cell carcinoma (RCC) progression. Preclinical evidence suggests that baseline elevated tumor glucose metabolism as quantified by FDG-PET ([18F] fluorodeoxy-glucose positron emission tomography) may predict antitumor activity. Metastatic RCC (mRCC) patients refractory to vascular endothelial growth factor (VEGF) pathway inhibition were treated with standard dose everolimus. FDG-PET scans were obtained at baseline and 2 weeks; serial computed tomography (CT) scans were obtained at baseline and every 8 weeks. Maximum standardized uptake value (SUVmax) of the most FDG avid lesion, average SUVmax of all measured lesions and their corresponding 2-week relative changes were examined for association with 8-week change in tumor size. A total of 63 patients were enrolled; 50 were evaluable for the primary endpoint of which 48 had both PET scans. Patient characteristics included the following: 36 (72%) clear cell histology and median age 59 (range: 37–80). Median pre- and 2-week treatment average SUVmax were 6.6 (1–17.9) and 4.2 (1–13.9), respectively. Response evaluation criteria in solid tumors (RECIST)-based measurements demonstrated an average change in tumor burden of 0.2% (−32.7% to 35.9%) at 8 weeks. Relative change in average SUVmax was the best predictor of change in tumor burden (all evaluable P = 0.01; clear cell subtype P = 0.02), with modest correlation. Baseline average SUVmax was correlated with overall survival and progression-free survival (PFS) (P = 0.023; 0.020), but not with change in tumor burden. Everolimus therapy decreased SUVs on follow-up PET scans in mRCC patients, but changes were only modestly correlated with changes in tumor size. Thus, clinical use of FDG-PET-based biomarkers is challenged by high variability. In this phase II trial, FDG-PET was explored as a

  20. Diagnostic Ability of FDG-PET/CT in the Detection of Malignant Pleural Effusion

    PubMed Central

    Nakajima, Reiko; Abe, Koichiro; Sakai, Shuji

    2015-01-01

    Abstract We investigated the role of F-18 fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) for the differential diagnosis of malignant and benign pleural effusion. We studied 36 consecutive patients with histologically proven cancer (excluding malignant mesothelioma) who underwent FDG-PET/CT for suspected malignant pleural effusion. Fourteen patients had cytologically proven malignant pleural effusion and the other 22 patients had either negative cytology or clinical follow-up, which confirmed the benign etiology. We examined the maximum standardized uptake values (SUVmax) of pleural effusion and the target-to-normal tissue ratio (TNR), calculated as the ratio of the pleural effusion SUVmax to the SUVmean of the normal tissues (liver, spleen, 12th thoracic vertebrae [Th12], thoracic aorta, and spinalis muscle). We also examined the size and density (in Hounsfield units) of the pleural effusion and pleural abnormalities on CT images. TNR (Th12) and increased pleural FDG uptake compared to background blood pool were significantly more frequent in cases with malignant pleural effusion (P < 0.05 for both). The cutoff TNR (Th12) value of >0.95 was the most accurate; the sensitivity, specificity, and accuracy for this value were 93%, 68%, and 75%, respectively. FDG-PET/CT can be a useful method for the differential diagnosis of malignant and benign pleural effusion. PMID:26200610

  1. FDG-PET imaging for the assessment of physiologic volume response during radiotherapy in cervix cancer

    SciTech Connect

    Lin, Lilie L.; Yang Zhiyun; Mutic, Sasa; Miller, Tom R.; Grigsby, Perry W. . E-mail: pgrigsby@wustl.edu

    2006-05-01

    Purpose: To evaluate the physiologic tumor volume response during treatment in cervical cancer using 18F-fluorodeoxyglucose positron emission tomography (FDG-PET). Patients and Methods: This was a prospective study of 32 patients. Physiologic tumor volume in cubic centimeters was determined from the FDG-PET images using the 40% threshold method. Results: The mean pretreatment tumor volume was 102 cm{sup 3}. The mean volume by clinical Stages I, II, and III were 54, 79, and 176 cm{sup 3}, respectively. After 19.8 Gy external irradiation to the pelvis, the reduction in tumor volume was 29% (72 cm{sup 3}). An additional 13 Gy from high-dose-rate (HDR) brachytherapy reduced the mean volume to 15.4 cm{sup 3}, and this was subsequently reduced to 8.6 cm{sup 3} with 13 Gy additional HDR brachytherapy (26 Gy, HDR). Four patients had physiologic FDG uptake in the cervix at 3 months after the completion of therapy. The mean time to the 50% reduction in physiologic tumor volume was 19.9 days and after combined external irradiation and HDR to 24.9 Gy. Conclusion: These results indicate that physiologic tumor volume determination by FDG-PET is feasible and that a 50% physiologic tumor volume reduction occurs within 20 days of starting therapy.

  2. Circulating microparticles bearing Fibrin associated with whole-body 18FDG-PET: diagnostic tools to detect paraneoplastic polymyalgia rheumatica.

    PubMed

    Mege, Diane; Cammilleri, Serge; Mundler, Olivier; Dignat-George, Françoise; Dubois, Christophe; Panicot-Dubois, Laurence; Guis, Sandrine

    2016-08-01

    Polymyalgia rheumatica (PMR), a chronic inflammatory rheumatism, can be the expression of a paraneoplastic syndrome. The same clinical symptoms are frequently observed at the early stage of the benign and malignant forms. Here, our aim was to develop diagnostic tools to differentiate paraneoplastic PMR from essential PMR. We combined an 18FDG-PET and detection of circulating procoagulant microparticles (MPs), such as fibrin positive (FibMPs), by flow cytometry. Two patients with PMR and a similar profile were selected. In the two patients, the 18FDG-PET revealed a hypermetabolic focus. However, the concentrations of fibrin+/annexin+ microparticles detected were (10 times higher in one of the two patients, who was later found to have breast cancer. The association of 18FDG-PET and the detection of microparticle fibrin positives by flow cytometry allows separating essential PMR (hypermetabolism by 18FDG-PET, low FibMPs) from paraneoplastic PMR. PMID:27324631

  3. Serial 18F-FDG PET/CT Findings in a Patient With IgLON5 Encephalopathy.

    PubMed

    Zhang, Wei; Niu, Na; Cui, Ruixue

    2016-10-01

    We presented the serial FDG PET/CT brain scans of a 64-year-old woman with IgLON5 encephalopathy, which is a novel syndrome in association with antibodies to a neuronal cell adhesion protein named IgLON5, and FDG PET findings have not been characterized previously. For our case, the relatively hypermetabolism in primary sensorimotor cortices, basal ganglia, and cerebrum comparing to other cortical regions on the pretreatment FDG PET/CT was partially recovered on the follow-up FDG PET/CT scan after immunotherapy, corresponding with the alleviation of clinical syndromes. The metabolic change pattern was not similar as other types of autoimmune encephalitis. PMID:27556794

  4. Comparative Analysis between [(18)F]Fludarabine-PET and [(18)F]FDG-PET in a Murine Model of Inflammation.

    PubMed

    Hovhannisyan, Narinée; Dhilly, Martine; Guillouet, Stéphane; Leporrier, Michel; Barré, Louisa

    2016-06-01

    Lymphoma research has advanced thanks to introduction of [(18)F]fludarabine, a positron-emitting tool. This novel radiotracer has been shown to display a great specificity for lymphoid tissues. However, in a benign process such as inflammation, the uptake of this tracer has not been questioned. Indeed, in inflammatory zones, elevated glucose metabolism rate may result in false-positives with [(18)F]FDG-PET Imaging. In the present investigation, it has been argued that cells, involved in inflammation, might be less avid of [(18)F]fludarabine. To generate inflammation, Swiss mice were intramuscularly injected with 0.1 mL of turpentine oil into the right front paw. Imaging sessions with (18)F-labeled tracers named above were conducted on days 5 and 25 after inoculation. For each animal, volumes of interest (VOI), delineating the muscle of the inflamed (IP) and normal paws (NP), were determined on PET scans. For characterization of inflammation, muscle samples from IP and NP were stained with hematoxylin and eosin (H&E). In early (day 5) inflammation, [(18)F]FDG accumulation was 4.00 ± 1.65 times greater in the IP than in the contralateral NP; for [(18)F]fludarabine, this IP/NP ratio was 1.31 ± 0.28, resulting in a significant difference between radiotracer groups (p < 0.01). In late (day 25) inflammation, the IP/NP ratios were 2.07 ± 0.49 and 1.03 ± 0.07, for [(18)F]FDG and [(18)F]fludarabine, respectively (p < 0.001). [(18)F]Fludarabine showed significantly weaker uptake in inflammation when compared with [(18)F]FDG. This encouraging finding suggests that [(18)F]fludarabine-PET might well be a robust approach for distinguishing tumor from inflammatory tissue, avoiding false-positive PET results and thus enabling an accurate imaging of lymphoma. PMID:27080099

  5. The value of 18F-FDG PET in pediatric patients with post-transplant lymphoproliferative disorder at initial diagnosis.

    PubMed

    Vali, R; Punnett, A; Bajno, L; Moineddin, R; Shammas, A

    2015-12-01

    PTLD is a serious complication of both solid organ and BMT. This study assessed whether (18) F-FDG PET, when added to CT scan, had additional value in the initial evaluation of PTLD in pediatric patients and whether PET/CT at baseline can reliably guide biopsy. This retrospective study evaluated 34 consecutive pediatric patients (14 female), aged 3.5-17.0 yr (mean age: 9.9 yr, s.d.: 4.9 yr), who had undergone (18) F-FDG PET/CT from May 2007 to December 2014 at initial diagnosis of PTLD following heart (n = 13), lung (n = 8), kidney (n = 4), liver (n = 3), liver and bowel (n = 3), and bone marrow (n = 3) transplantation. PTLD was diagnosed histopathologically in 33 patients and was based on clinical findings, elevated EBV, and imaging and follow-up results in one patient. On lesion-based analysis, (18) F-FDG PET showed more lesions than conventional CT scan (168 vs. 134), but CT revealed 22 lesions negative on PET. On per patient analysis, PET detected more lesions in 13 patients, CT identified more abnormalities in seven, and both showed the same number of lesions in 14. Adding (18) F-FDG PET to CT scans upstaged the disease in seven patients (20.5%). A combination of (18) F-FDG PET and CT was also useful in guiding biopsy, being positive in 36 of 39 samples (92.3%). These findings indicated that (18) F-FDG PET and CT are complementary at initial staging of pediatric PTLD and that (18) F-FDG PET/CT scanning can guide biopsies. PMID:26515450

  6. Imaging of Hepatic Ectopic Pregnancy by 18F-FDG PET/CT.

    PubMed

    Hao, Jingwen; Cheng, Zhen; Hu, Na; Xiao, Lizhi; Wang, Yunhua

    2016-09-01

    Hepatic ectopic pregnancy is an uncommon form of extrauterine pregnancy. A 31-year-old woman had acute abdominal pain and distention. Laboratory examination showed significantly increased serum β-human chorionic gonadotropin level. Both ultrasound and MRI identified a lesion located at the right lobe of the liver. FDG PET/CT was performed to determine whether the other causes of elevated β-human chorionic gonadotropin level, which showed an oval mass with mid peripherally increased FDG activity. After surgery, pathological results confirmed a diagnosis of hepatic ectopic pregnancy. PMID:27454601

  7. 18F-FDG PET/CT Osteometabolic Activity in Metastatic Parathyroid Carcinoma.

    PubMed

    do Vale, Rômulo Hermeto Bueno; Queiroz, Marcelo Araújo; Coutinho, Artur Martins Novaes; Buchpiguel, Carlos Alberto; de Menezes, Marcos Roberto

    2016-09-01

    Parathyroid cancer is an uncommon type of malignancy, which is frequently associated with poor prognosis. Clinical manifestations are caused by elevated serum calcium and parathyroid hormone (PTH). Diagnostic imaging studies as neck ultrasonography, technetium Tc Tc-sestamibi whole body scintigraphy, CT, and MR are already established tools for this malignancy. Nevertheless, the role of F-FDG PET/CT remains unknown in this scenario, with few published studies in literature. Hence, in this article, we aimed to report an illustrative case of increased skeletal FDG uptake associated with high calcium and PTH levels. PMID:27276208

  8. FDG PET/CT Findings in Multiple Splenic Amebomas (Amebic Granulomas).

    PubMed

    Dong, Aisheng; Wang, Yang; Zuo, Changjing; Zhu, Huaimin

    2016-05-01

    Splenic ameboma (amebic granuloma) is rare. A 38-year-old man with a severe pneumonia due to inhalation of swimming pool water 18 months ago complained of night sweat, tiredness, and anorexia for 1 month. Abdominal ultrasound showed multiple nodules in the spleen. These nodules showed slight enhancement on enhanced CT and intense FDG uptake on PET/CT. Splenectomy was performed. Multiple splenic amebomas were confirmed by pathology. Free-living amoebae were also detected in samples of pleural effusion and blood. Splenic ameboma, although rare, should be included in the differential diagnosis with isolated focally increased FDG activity in the spleen. PMID:26505858

  9. Chronic Esophageal Perforation With Periesophageal Abscess Mimicking Malignancy on FDG PET/CT.

    PubMed

    Dong, Aisheng; Zhang, Ling; Wang, Yang; Zuo, Changjing

    2016-06-01

    A 53-year-old man was admitted because of progressive dysphagia and retrosternal pain for 20 days. Esophagogastroduodenoscopy showed an irregular submucosal bulge on the distal esophageal wall. A barium swallow showed a triangular-shaped outpouching of contrast material with minimal contained extravasation into the periesophageal area. Enhanced CT showed thickening of the distal esophagus with an area containing air and septa. FDG PET/CT showed intense FDG uptake of the thickened esophageal wall mimicking malignancy. Endoscopic ultrasonography-guided biopsy of the submucosal mass revealed granulation tissue. The imaging and pathologic findings were consistent with chronic esophageal perforation with periesophageal abscess. PMID:26914572

  10. Increased 18F-FDG Uptake Associated With Gastric Banding Surgical Mesh on PET/CT.

    PubMed

    Chism, Charles B; Somcio, Ray; Chasen, Beth A; Ravizzini, Gregory C

    2016-05-01

    Surgical mesh was used in the 1980s and early 1990s for vertical banded gastroplasty as treatment for morbid obesity. This procedure was replaced by the more popular laparoscopic gastric banding in the mid-1990s. Surgical mesh, commonly used in hernioplasty, has been associated with increased F-FDG uptake related to an inflammatory foreign body reaction and is a known cause of false-positive PET scans. We present a case of increased F-FDG uptake related to surgical mesh in a patient who had undergone vertical banded gastroplasty. PMID:26825203

  11. Clinical significance of patterns of incidental thyroid uptake at (18)F-FDG PET/CT.

    PubMed

    Agrawal, K; Weaver, J; Ngu, R; Krishnamurthy Mohan, H

    2015-05-01

    Incidental uptake of 2-[(18)F]-fluoro-2-deoxy-d-glucose ((18)F-FDG) in the thyroid gland is not uncommonly encountered in day-to-day practice of oncological (18)F-FDG positron-emission tomography/computed tomography (PET/CT). These are often felt to be "nuisance lesions" by referring clinicians and radiologists alike. However, recognition of the importance of different patterns of FDG uptake in the thyroid gland and knowledge of the possible underlying aetiologies are crucial in ensuring that patients are managed appropriately in the clinical context of their primary diagnosis, as the underlying pathological condition may be clinically important in a significant minority of such cases. This review describes the various patterns of (18)F-FDG uptake within the thyroid and discusses the clinical significance and possible impact on patient management. Incidental low-grade homogeneous diffuse increased thyroid (18)F-FDG uptake is usually seen in the patients with chronic thyroiditis, Grave's disease, and hypothyroidism. Thyroid function tests and antibody profiling are advised in these patients. Incidental focal (18)F-FDG thyroid uptake should raise the possibility of underlying malignancy. Ultrasound with or without fine-needle aspiration cytology is usually recommended for the evaluation of these lesions. Heterogeneous uptake with prominent focal uptake in the thyroid should be further evaluated to exclude malignancy. PMID:25687827

  12. Occult Mediastinal Yolk Sac Tumor Producing α-Fetoprotein Detected by 18F-FDG PET/CT.

    PubMed

    Liu, Meng; Chen, Guoqian; Fu, Zhanli; Li, Ziao; Li, Qian

    2016-07-01

    Malignant mediastinal yolk sac tumor (YST), especially adult onset, is rare. Herein, we report a case of occult mediastinal YST with α-fetoprotein production revealed by F-FDG PET/CT in a young adult, in which the intense tracer uptake was demonstrated in the anterior mediastinum. This case indicates F-FDG PET/CT may be a useful tool for detecting the occult primaries of YST. PMID:27088388

  13. Adrenal tuberculosis masquerading as disseminated malignancy: A pitfall of (18)F-FDG PET/CT Imaging.

    PubMed

    Gorla, A K R; Gupta, K; Sood, A; Biswal, C K; Bhansali, A; Mittal, B R

    2016-01-01

    Non-invasive characterization of adrenal lesions is a commonly encountered diagnostic challenge. Characteristic clinical and correlative imaging findings may assist in only arriving at a probable diagnosis. Currently, (18)F-FDG PET/CT is considered to provide the most comprehensive imaging information. We here present a case of bilateral adrenal tuberculosis that highlights the need for caution during the interpretation of (18)F-FDG PET/CT and also the need to suggest histopathological correlation. PMID:26853485

  14. Histopathologic Validation of Lymph Node Staging With FDG-PET Scan in Cancer of the Esophagus and Gastroesophageal Junction

    PubMed Central

    Lerut, Toni; Flamen, Patrick; Ectors, Nadine; Van Cutsem, Erik; Peeters, Marc; Hiele, Martin; De Wever, Walter; Coosemans, Willy; Decker, Georges; De Leyn, Paul; Deneffe, Georges; Van Raemdonck, Dirk; Mortelmans, Luc

    2000-01-01

    Objective To assess the value of positron emission tomography with 18fluorodeoxyglucose (FDG-PET) for preoperative lymph node staging of patients with primary cancer of the esophagus and gastroesophageal junction. Summary Background Data FDG-PET appears to be a promising tool in the preoperative staging of cancer of the esophagus and gastroesophageal junction. Recent reports indicate a higher sensitivity and specificity for detection of stage IV disease and a higher specificity for diagnosis of lymph node involvement compared with the standard use of computed tomography and endoscopic ultrasound. Methods Forty-two patients entered the prospective study. All underwent attenuation-corrected FDG-PET imaging of the neck, thorax, and upper abdomen, a spiral computed tomography scan, and an endoscopic ultrasound. The gold standard consisted exclusively of the histology of sampled nodes obtained by extensive two-field or three-field lymphadenectomies (n = 39) or from guided biopsies of suspicious distant nodes indicated by imaging (n = 3). Results The FDG-PET scan had lower accuracy for the diagnosis of locoregional nodes (N1–2) than combined computed tomography and endoscopic ultrasound (48% vs. 69%) because of a significant lack of sensitivity (22% vs. 83%). The accuracy for distant nodal metastasis (M+Ly), however, was significantly higher for FDG-PET than the combined use of computed tomography and endoscopic ultrasound (86% vs. 62%). Sensitivity was not significantly different, but specificity was greater (90% vs. 69%). The FDG-PET scan correctly upstaged five patients (12%) from N1–2 stage to M+Ly stage. One patient was falsely downstaged by FDG-PET scanning. Conclusions FDG-PET scanning improves the clinical staging of lymph node involvement based on the increased detection of distant nodal metastases and on the superior specificity compared with conventional imaging modalities. PMID:11088069

  15. Active herpes zoster infection with cutaneous manifestation and adenopathy on FDG PET/CT

    PubMed Central

    Wadih, Antoine; Rehm, Patrice K.; Deng, Chunli; Douvas, Michael

    2015-01-01

    We report a patient with history of Hodgkin lymphoma. Six months after treatment, 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography and/or computed tomography ([18F] FDG PET/CT) scan showed abnormal uptake in right axillary lymph nodes concerning for recurrence. In addition, PET/CT showed a new hypermetabolic skin lesion overlying the right scapula. Clinical evaluation was consistent with shingles, and the patient was treated with valacyclovir. Subsequent PET/CT scan was normal with no evidence of lymphoma. Although there have been reported cases of abnormal FDG in nodes or in skin due to herpes zoster, our case is unique in the literature in that the PET/CT demonstrates abnormalities involving both the skin and associated lymph nodes. The possibility of false positive uptake, not because of recurrent malignancy, must always be considered when abnormal FDG uptake is noted in the follow-up of oncology patients. Careful review of the scan and correlation with clinical findings can avoid false positive interpretation and facilitate patient management. PMID:26649113

  16. Active herpes zoster infection with cutaneous manifestation and adenopathy on FDG PET/CT.

    PubMed

    Wadih, Antoine; Rehm, Patrice K; Deng, Chunli; Douvas, Michael

    2015-10-01

    We report a patient with history of Hodgkin lymphoma. Six months after treatment, 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography and/or computed tomography ([18F] FDG PET/CT) scan showed abnormal uptake in right axillary lymph nodes concerning for recurrence. In addition, PET/CT showed a new hypermetabolic skin lesion overlying the right scapula. Clinical evaluation was consistent with shingles, and the patient was treated with valacyclovir. Subsequent PET/CT scan was normal with no evidence of lymphoma. Although there have been reported cases of abnormal FDG in nodes or in skin due to herpes zoster, our case is unique in the literature in that the PET/CT demonstrates abnormalities involving both the skin and associated lymph nodes. The possibility of false positive uptake, not because of recurrent malignancy, must always be considered when abnormal FDG uptake is noted in the follow-up of oncology patients. Careful review of the scan and correlation with clinical findings can avoid false positive interpretation and facilitate patient management. PMID:26649113

  17. Interobserver and Intraobserver Variability among Measurements of FDG PET/CT Parameters in Pulmonary Tumors

    PubMed Central

    Büyükdereli, Gülgün; Güler, Mehtap; şeydaoğlu, Gülşah

    2016-01-01

    Background: 18F-fluorodeoxyglucose (FDG) positron emission tomography computed tomography (PET/CT) provides information about metabolic and morphologic status of malignancies. Tumor size and standardized uptake value (SUV) measurements are crucial for cancer treatment monitoring. Aims: The purpose of our study was to assess the variability of these measurements performed by observers evaluating lung tumors. Study Design: Retrospective cross-sectional study. Methods: FDG PET/CT images of 97 patients with pulmonary tumors were independently evaluated by two experienced nuclear medicine physicians. Primary tumor size (UDCT), maximum SUV (SUVmax), mean SUV (SUVmean) and maximum SUV normalized to liver mean SUV (SUVnliv max) were measured by each observer at two different times with an interval of at least 2 weeks. Interobserver and intraobserver variabilities of measurements were evaluated through statistical methods. Results: Size of the lesions varied from 0.81 to 13.6 cm (mean 4.29±2.24 cm). Very good agreement was shown with correlation, Bland-Altman and regression analysis for all measured PET/CT parameters. In the interobserver and intraobserver variability analysis, the Pearson correlation coefficients were greater than 0.96 and 0.98, respectively. Conclusion: Semi-quantitative measurements of pulmonary tumors were highly reproducible when determined by experienced physicians with clinically available software for routine FDG PET/CT evaluation. Consistency may be improved if the same observer performs serial measurements for any one patient. PMID:27308075

  18. 18F-FDG PET/CT Imaging of Primary Hepatic Neuroendocrine Tumor

    PubMed Central

    Mitamura, Katsuya; Yamamoto, Yuka; Tanaka, Kenichi; Sanomura, Takayuki; Murota, Makiko; Nishiyama, Yoshihiro

    2015-01-01

    Primary hepatic neuroendocrine tumors (PHNETs) are extremely rare neoplasms. Herein, we report a case of a 70- year-old man with a hepatic mass. The non-contrast computed tomography (CT) image showed a low-density mass, and dynamic CT images indicated the enhancement of the mass in the arterial phase and early washout in the late phase. F-18 fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) and fused PET/CT images showed increased uptake in the hepatic mass. Whole-body 18F-FDG PET images showed no abnormal activity except for the liver lesion. Presence of an extrahepatic tumor was also ruled out by performing upper gastrointestinal endoscopy, total colonoscopy, and chest and abdominal CT. A posterior segmentectomy was performed, and histologic examination confirmed a neuroendocrine tumor (grade 1). The patient was followed up for about 2 years after the resection, and no extrahepatic lesions were radiologically found. Therefore, the patient was diagnosed with PHNET. To the best of our knowledge, no previous case of PHNET have been detected by 18F-FDG PET imaging.

  19. (18)F-FDG PET/CT Imaging of Primary Hepatic Neuroendocrine Tumor.

    PubMed

    Mitamura, Katsuya; Yamamoto, Yuka; Tanaka, Kenichi; Sanomura, Takayuki; Murota, Makiko; Nishiyama, Yoshihiro

    2015-01-01

    Primary hepatic neuroendocrine tumors (PHNETs) are extremely rare neoplasms. Herein, we report a case of a 70- year-old man with a hepatic mass. The non-contrast computed tomography (CT) image showed a low-density mass, and dynamic CT images indicated the enhancement of the mass in the arterial phase and early washout in the late phase. F-18 fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) and fused PET/CT images showed increased uptake in the hepatic mass. Whole-body (18)F-FDG PET images showed no abnormal activity except for the liver lesion. Presence of an extrahepatic tumor was also ruled out by performing upper gastrointestinal endoscopy, total colonoscopy, and chest and abdominal CT. A posterior segmentectomy was performed, and histologic examination confirmed a neuroendocrine tumor (grade 1). The patient was followed up for about 2 years after the resection, and no extrahepatic lesions were radiologically found. Therefore, the patient was diagnosed with PHNET. To the best of our knowledge, no previous case of PHNET have been detected by (18)F-FDG PET imaging. PMID:27408882

  20. FDG PET and tumour markers in the diagnosis of recurrent and metastatic breast cancer.

    PubMed

    Siggelkow, Wulf; Rath, Werner; Buell, Udalrich; Zimny, Michael

    2004-06-01

    Breast cancer continues to be one of the most common cancers in North America and Western Europe. Positron emission tomography with 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG PET) represents a non-invasive functional imaging modality that is based on metabolic characteristics of malignant tumours. In breast cancer, FDG PET is more accurate than conventional methods for staging of distant metastases or local recurrences and enables early assessment of treatment response in patients undergoing primary chemotherapy. Recent data indicate a rationale for the use of FDG PET in cases of asymptomatically elevated tumour marker levels in the presence of uncertain results of conventional imaging. Despite the fact that PET cannot rule out microscopic disease, it does have particular value in providing, in a single examination, a reliable assessment of the true extent of the disease. This technique is complementary to morphological imaging for primary diagnosis, staging and re-staging. It may become the method of choice for the assessment of asymptomatic patients with elevated tumour marker levels. This method, however, cannot replace invasive procedures if microscopic disease is of clinical relevance. PMID:15146295

  1. FDG-PET in the selection of brain lesions for biopsy

    SciTech Connect

    Hanson, M.W.; Glantz, M.J.; Hoffman, J.M.; Friedman, A.H.; Burger, P.C.; Schold, S.C.; Coleman, R.E. )

    1991-09-01

    The CT-guided stereotaxic needle biopsy has become a widely used procedure in the diagnostic evaluation of intracranial lesions including tumors. Conventional CT or MR frequently defines the anatomic regions of abnormality, which may be multiple lesions or a single lesion that is heterogeneous in cellular composition owing to the topographic variation of cellular constituency or the combination of active disease, nonspecific inflammation, necrosis, and/or edema. In these cases, selection of the most appropriate site for a successful diagnostic needle biopsy can be difficult. In three patients, we have used (18F)fluorodeoxyglucose (FDG) positron emission tomography (PET) to determine the site most likely to provide a diagnostic biopsy result. In the first patient, who presented with confusion, multiple biopsies from the temporal lobe, based on MR abnormalities, revealed only reactive gliosis and edema. Repeat biopsy directed by PET revealed an anaplastic astrocytoma. In a second patient, PET allowed us to differentiate radiation effect from active metastatic breast cancer. In the third patient, who presented with a grand mal seizure, biopsy of a CT-defined hypodense region demonstrated lymphocytosis. Metabolism of FDG was normal or increased in areas of Aspergillus encephalitis at autopsy. These preliminary studies suggest a complementary role for FDG-PET and CT or MR in selected patients for defining the intracranial site most likely to yield a positive biopsy result.

  2. The role of FDG-PET/CT in the evaluation of residual disease in paediatric non-Hodgkin lymphoma.

    PubMed

    Bhojwani, Deepa; McCarville, Mary B; Choi, John K; Sawyer, Jennifer; Metzger, Monika L; Inaba, Hiroto; Davidoff, Andrew M; Gold, Robert; Shulkin, Barry L; Sandlund, John T

    2015-03-01

    (18) F-labelled-fluorodeoxyglucose positron emission tomography (FDG-PET) findings are challenging to interpret for residual disease versus complete response in paediatric patients with non-Hodgkin lymphoma (NHL). A biopsy is often warranted to confirm the presence or absence of viable tumour if there is clinical or radiographic evidence of residual disease. In this study, we compared conventional imaging and FDG-PET/computerized tomography (CT) findings with biopsy results in 18 children with NHL. Our goal was to provide additional data to establish more reliable criteria for response evaluation. Residual disease was suspected after conventional imaging alone in eight patients, after FDG-PET/CT alone in three and after both modalities in seven patients. Biopsy confirmed the presence of viable tumour in two patients. Two additional patients experienced progressive disease or relapse. The sensitivity and negative predictive value of FDG-PET/CT using the London criteria to indicate residual tumour detectable by biopsy were 100%, but specificity was low (60%), as was the positive predictive value (25%). Thus, in this study, a negative FDG-PET/CT finding was a good indicator of complete remission. However, because false-positive FDG-PET/CT findings are common, biopsy and close monitoring are required for accurate determination of residual disease in individual patients. PMID:25382494

  3. (18)F-FDG-PET/CT and (18)F-NaF-PET/CT in men with castrate-resistant prostate cancer.

    PubMed

    Zukotynski, Katherine A; Kim, Chun K; Gerbaudo, Victor H; Hainer, Jon; Taplin, Mary-Ellen; Kantoff, Philip; den Abbeele, Annick D Van; Seltzer, Steven; Sweeney, Christopher J

    2015-01-01

    To evaluate (18)F-labeled-fluorodeoxyglucose ((18)F-FDG-) and (18)F-labeled-sodium fluoride ((18)F-NaF-) positron emission tomography/computed tomography (PET/CT) as biomarkers in metastatic castrate-resistant prostate cancer (mCRPC). Nine men (53-75 years) in a phase 1 trial of abiraterone and cabozantinib had (18)F-FDG-PET/CT, (18)F-NaF-PET/CT and standard imaging ((99m)Tc-labeled-methylene-diphosphonate ((99m)Tc-MDP) bone scan and abdominal/pelvic CT) at baseline and after 8 weeks of therapy. Baseline disease was classified as widespread (18)F-FDG-avid, oligometastatic (18)F-FDG-avid (1 site), or non-(18)F-FDG-avid. Metabolic response was classified using European Organisation for Research and Treatment of Cancer (EORTC) criteria. Treatment response using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, Prostate Cancer Working Group 2 (PCWG2) guidelines and days on trial (DOT) were recorded. All men were followed for 1 year or until progression. Four men had (18)F-FDG-avid disease: two with widespread (DOT 53 and 76) and two with oligometastatic disease (DOT 231 and still on trial after 742+ days). Five men had non-(18)F-FDG-avid disease; three remained stable or improved (2 still on trial while one discontinued for non-oncologic reasons; DOT 225-563+), and 2 progressed (DOT 285 and 532). Despite the small sample size, Kaplan-Meier analysis showed a significant difference in progression free survival (PFS) between men with widespread (18)F-FDG-avid, oligometastatic (18)F-FDG-avid and non-(18)F-FDG-avid disease (p < 0.01). All men had (18)F-NaF-avid disease. Neither (18)F-NaF-avid disease extent nor intensity was predictive of treatment response. (18)F-FDG-PET/CT may be superior to (18)F-NaF-PET/CT and standard imaging in men with mCRPC on abiraterone and cabozantinib. (18)F-FDG-PET/CT may have potential to stratify men into 3 groups (widespread vs. oligometastatic (18)F-FDG-avid vs. non-(18)F-FDG-avid mCRPC) to tailor therapy. Further evaluation is

  4. 18F-FDG PET/CT Role in Staging of Gastric Carcinomas: Comparison with Conventional Contrast Enhancement Computed Tomography

    PubMed Central

    Altini, Corinna; Niccoli Asabella, Artor; Di Palo, Alessandra; Fanelli, Margherita; Ferrari, Cristina; Moschetta, Marco; Rubini, Giuseppe

    2015-01-01

    Abstract The purpose of the report was to evaluate the role of fluorine-18 fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) in staging gastric cancer comparing it with contrast enhancement computed tomography (CECT). This retrospective study included 45 patients who underwent performed whole body CECT and 18F-FDG PET/CT before any treatment. We calculated CECT and 18F-FDG PET/CT sensitivity, specificity, accuracy, positive and negative predictive values (PPV and NPV) for gastric, lymphnode, and distant localizations; furthermore, we compared the 2 techniques by McNemar test. The role of 18F-FDG PET/CT semiquantitative parameters in relation to histotype, grading, and site of gastric lesions were evaluated by ANOVA test. Sensitivity, specificity, accuracy, PPV and NPV of CECT, and 18F-FDG PET/CT for gastric lesion were, respectively, 92.11%, 57.14%, 86.66%, 92.11%, 57.14% and 81.58%, 85.71%, 82.22%, 96.88%, 46.15%. No differences were identified between the 2 techniques about sensitivity and specificity. No statistical differences were observed between PET parameters and histotype, grading, and site of gastric lesion. The results of CECT and 18F-FDG PET/CT about lymphnode involvement were 70.83%, 61.90%, 66.66%, 68%, 65% and 58.33%, 95.24%, 75.55%, 93.33%, 66.67%. The results of CECT and 18F-FDG PET/CT about distant metastases were 80%, 62.86%, 66.66%, 38.10%, 91.67% and 60%, 88.57%, 82.22%, 60%, 88.57%. 18FDG PET/CT specificity was significantly higher both for lymphnode and distant metastases. The 18F-FDG PET/CT is a useful tool for the evaluation of gastric carcinoma to detect primary lesion, lymphnode, and distant metastases using 1 single image whole-body technique. Integration of CECT with 18F-FDG PET/CT permits a more valid staging in these patients. PMID:25997066

  5. False-Positive Finding on 18F FDG PET/CT: Report of a Rare Case With Xanthogranulomatous Inflammation in the Spinal Epidural Space.

    PubMed

    Alam, Mohammed Shah; Guan, Wei; Zhou, Wen-Lan; Wang, Quan-Shi; Wu, Hu-Bing

    2016-09-01

    Xanthogranulomatous inflammation in the spinal epidural space is extremely rare. We report a case of a 62-year-old man with a xanthogranulomatous inflammation in the spinal epidural space mistaken for lymphoma because of its avid F FDG uptake on PET/CT. This case emphasizes the need for caution when evaluating a spinal epidural mass using F FDG PET/CT as xanthogranulomatous inflammation can induce a false-positive reading on F-FDG PET/CT. PMID:27276211

  6. The relationship between hallucinations and FDG-PET in dementia with Lewy bodies.

    PubMed

    Firbank, Michael J; Lloyd, Jim; O'Brien, John T

    2016-09-01

    Visual hallucinations are common in dementia with Lewy bodies (DLB), although their etiology is unclear. This study aimed to investigate the relationship between severity and frequency of hallucinations and regional brain glucose metabolism. We performed brain FDG-PET scanning on 28 subjects with DLB (mean age 76). The neuropsychiatric index (NPI) was used to assess frequency and severity of hallucinations. We used the SPM package to investigate voxelwise correlations between NPI hallucination score (severity x frequency) and FDG uptake relative to the cerebellum. There was a bilateral medial occipital region where reduced FDG was associated with increased hallucination severity and frequency. We conclude that the reduced occipital metabolism frequently seen in DLB is associated with frequency and severity of visual hallucinations. Further studies are required to investigate whether this is the result of deficits in top-down or bottom-up visual processing pathways. PMID:26239998

  7. 18F-FDG PET/CT and PET/MRI Perform Equally Well in Cancer: Evidence from Studies on More Than 2,300 Patients.

    PubMed

    Spick, Claudio; Herrmann, Ken; Czernin, Johannes

    2016-03-01

    (18)F-FDG PET/CT has become the reference standard in oncologic imaging against which the performance of other imaging modalities is measured. The promise of PET/MRI includes multiparametric imaging to further improve diagnosis and phenotyping of cancer. Rather than focusing on these capabilities, many investigators have examined whether (18)F-FDG PET combined with mostly anatomic MRI improves cancer staging and restaging. After a description of PET/MRI scanner designs and a discussion of technical and operational issues, we review the available literature to determine whether cancer assessments are improved with PET/MRI. The available data show that PET/MRI is feasible and performs as well as PET/CT in most types of cancer. Diagnostic advantages may be achievable in prostate cancer and in bone metastases, whereas disadvantages exist in lung nodule assessments. We conclude that (18)F-FDG PET/MRI and PET/CT provide comparable diagnostic information when MRI is used simply to provide the anatomic framework. Thus, PET/MRI could be used in lieu of PET/CT if this approach becomes economically viable and if reasonable workflows can be established. Future studies should explore the multiparametric potential of MRI. PMID:26742709

  8. Quantitative Assessment of Heterogeneity in Tumor Metabolism Using FDG-PET

    SciTech Connect

    Vriens, Dennis; Disselhorst, Jonathan A.; Oyen, Wim J.G.; Geus-Oei, Lioe-Fee de; Visser, Eric P.

    2012-04-01

    Purpose: [{sup 18}F]-fluorodeoxyglucose-positron emission tomography (FDG-PET) images are usually quantitatively analyzed in 'whole-tumor' volumes of interest. Also parameters determined with dynamic PET acquisitions, such as the Patlak glucose metabolic rate (MR{sub glc}) and pharmacokinetic rate constants of two-tissue compartment modeling, are most often derived per lesion. We propose segmentation of tumors to determine tumor heterogeneity, potentially useful for dose-painting in radiotherapy and elucidating mechanisms of FDG uptake. Methods and Materials: In 41 patients with 104 lesions, dynamic FDG-PET was performed. On MR{sub glc} images, tumors were segmented in quartiles of background subtracted maximum MR{sub glc} (0%-25%, 25%-50%, 50%-75%, and 75%-100%). Pharmacokinetic analysis was performed using an irreversible two-tissue compartment model in the three segments with highest MR{sub glc} to determine the rate constants of FDG metabolism. Results: From the highest to the lowest quartile, significant decreases of uptake (K{sub 1}), washout (k{sub 2}), and phosphorylation (k{sub 3}) rate constants were seen with significant increases in tissue blood volume fraction (V{sub b}). Conclusions: Tumor regions with highest MR{sub glc} are characterized by high cellular uptake and phosphorylation rate constants with relatively low blood volume fractions. In regions with less metabolic activity, the blood volume fraction increases and cellular uptake, washout, and phosphorylation rate constants decrease. These results support the hypothesis that regional tumor glucose phosphorylation rate is not dependent on the transport of nutrients (i.e., FDG) to the tumor.

  9. Combined Modality Treatment for PET-Positive Non-Hodgkin Lymphoma: Favorable Outcomes of Combined Modality Treatment for Patients With Non-Hodgkin Lymphoma and Positive Interim or Postchemotherapy FDG-PET

    SciTech Connect

    Halasz, Lia M.; Jacene, Heather A.; Catalano, Paul J.; Van den Abbeele, Annick D.; LaCasce, Ann; Mauch, Peter M.; Ng, Andrea K.

    2012-08-01

    Purpose: To evaluate outcomes of patients treated for aggressive non-Hodgkin lymphoma (NHL) with combined modality therapy based on [{sup 18}F]fluoro-2-deoxy-2-D-glucose positron emission tomography (FDG-PET) response. Methods and Materials: We studied 59 patients with aggressive NHL, who received chemotherapy and radiation therapy (RT) from 2001 to 2008. Among them, 83% of patients had stage I/II disease. Patients with B-cell lymphoma received R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone)-based chemotherapy, and 1 patient with anaplastic lymphoma kinase-negative anaplastic T-cell lymphoma received CHOP therapy. Interim and postchemotherapy FDG-PET or FDG-PET/computed tomography (CT) scans were performed for restaging. All patients received consolidated involved-field RT. Median RT dose was 36 Gy (range, 28.8-50 Gy). Progression-free survival (PFS) and local control (LC) rates were calculated with and without a negative interim or postchemotherapy FDG-PET scan. Results: Median follow-up was 46.5 months. Thirty-nine patients had negative FDG-PET results by the end of chemotherapy, including 12 patients who had a negative interim FDG-PET scan and no postchemotherapy PET. Twenty patients were FDG-PET-positive, including 7 patients with positive interim FDG-PET and no postchemotherapy FDG-PET scans. The 3-year actuarial PFS rates for patients with negative versus positive FDG-PET scans were 97% and 90%, respectively. The 3-year actuarial LC rates for patients with negative versus positive FDG-PET scans were 100% and 90%, respectively. Conclusions: Patients who had a positive interim or postchemotherapy FDG-PET had a PFS rate of 90% at 3 years after combined modality treatment, suggesting that a large proportion of these patients can be cured with consolidated RT.

  10. 18F-FDG-PET/CT in lymphoma: two decades of experience.

    PubMed

    Alvarez Páez, A M; Nogueiras Alonso, J M; Serena Puig, A

    2012-01-01

    The use of (18)F-FDG-PET/CT has changed the management of patients with lymphoma for the last two decades. This technique improves initial staging of the disease, making a prognostic approach and appropriate treatment planning, as well as monitoring therapy response of lymphoma. However, there are still controversial issues in medical literature that impact on daily clinical practice. This comprehensive literature review summarizes the current information regarding the potential use of (18)F-FDG-PET/CT in patients with lymphoma, highlighting the main applications and the current dilemmas for the nuclear medicine physicians at the time of the evaluation of these studies, trying to standardize criteria for its assessment, particularly in restaging and therapy monitoring. PMID:22841459

  11. Small Animal Retinal Imaging

    NASA Astrophysics Data System (ADS)

    Choi, WooJhon; Drexler, Wolfgang; Fujimoto, James G.

    Developing and validating new techniques and methods for small animal imaging is an important research area because there are many small animal models of retinal diseases such as diabetic retinopathy, age-related macular degeneration, and glaucoma [1-6]. Because the retina is a multilayered structure with distinct abnormalities occurring in different intraretinal layers at different stages of disease progression, there is a need for imaging techniques that enable visualization of these layers individually at different time points. Although postmortem histology and ultrastructural analysis can be performed for investigating microscopic changes in the retina in small animal models, this requires sacrificing animals, which makes repeated assessment of the same animal at different time points impossible and increases the number of animals required. Furthermore, some retinal processes such as neurovascular coupling cannot be fully characterized postmortem.

  12. Case Reports on the Differentiation of Malignant and Benign Intratracheal Lesions by 18F-FDG PET/CT

    PubMed Central

    Chun, Kyung-Ah

    2015-01-01

    Abstract Malignant tracheal tumors (primary and secondary) are rare and benign tumors of the tracheobronchial tree are also rare. Few reports have been issued on the 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) findings of tracheal tumors or benign nontumorous tracheal lesions, which have been mainly studied by computed tomography (CT). The author reports 2 cases of intratracheal lesions with quite different 18F-FDG PET/CT findings. The first case was of a 73-year-old woman with colon cancer treated by hemicolectomy and subsequent adjuvant chemotherapy. Follow-up 18F-FDG PET/CT after 6 years revealed a hypermetabolic fungating mass (SUVmax: 5.8) in the distal trachea and biopsy confirmed intratracheal metastasis. The second case involved a 61-year-old man with tongue cancer who underwent mouth floor mass excision and right supraomohyoid neck dissection with submental flap reconstruction. Tracheal lesion was incidentally found during a 18F-FDG PET/CT follow-up study conducted 1 year later. A benign intratracheal condition with low FDG uptake (SUVmax: 1.2) and the lesion was not visualized by neck CT 4 months later. 18F-FDG PET/CT uptake was helpful in differentiating benign and malignant intratracheal lesions. PMID:26554767

  13. Case Reports on the Differentiation of Malignant and Benign Intratracheal Lesions by 18F-FDG PET/CT.

    PubMed

    Chun, Kyung-Ah

    2015-11-01

    Malignant tracheal tumors (primary and secondary) are rare and benign tumors of the tracheobronchial tree are also rare. Few reports have been issued on the F-fluorodeoxyglucose (F-FDG) positron emission tomography (PET) findings of tracheal tumors or benign nontumorous tracheal lesions, which have been mainly studied by computed tomography (CT). The author reports 2 cases of intratracheal lesions with quite different F-FDG PET/CT findings. The first case was of a 73-year-old woman with colon cancer treated by hemicolectomy and subsequent adjuvant chemotherapy. Follow-up F-FDG PET/CT after 6 years revealed a hypermetabolic fungating mass (SUVmax: 5.8) in the distal trachea and biopsy confirmed intratracheal metastasis. The second case involved a 61-year-old man with tongue cancer who underwent mouth floor mass excision and right supraomohyoid neck dissection with submental flap reconstruction. Tracheal lesion was incidentally found during a F-FDG PET/CT follow-up study conducted 1 year later. A benign intratracheal condition with low FDG uptake (SUVmax: 1.2) and the lesion was not visualized by neck CT 4 months later. F-FDG PET/CT uptake was helpful in differentiating benign and malignant intratracheal lesions. PMID:26554767

  14. Stage-dependent agreement between cerebrospinal fluid proteins and FDG-PET findings in Alzheimer's disease.

    PubMed

    Yakushev, Igor; Muller, Matthias J; Buchholz, Hans-Georg; Lang, Ulrike; Rossmann, Heidi; Hampel, Harald; Schreckenberger, Mathias; Fellgiebel, Andreas

    2012-02-01

    Cerebral hypometabolism and abnormal levels of amyloid beta (Aβ), total (t-tau) and phosphorylated tau (ptau) proteins in cerebrospinal fluid (CSF) are established biomarkers of Alzheimer's disease (AD). We examined the agreement between these biomarkers in a single center study of patients with AD of severity extending over a wide range. Forty seven patients (MMSE 21.4 ± 3.6, range 13-28 points) with incipient and probable AD underwent positron emission tomography with [18F]-fluorodeoxyglucose (FDG-PET) and lumbar puncture for CSF assays of Aβ1-42, p-tau181, and t-tau. All findings were classified as either positive or negative for AD. Statistical analyses were performed for the whole sample (n=47) and for the subgroups stratified as mild (MMSE > 20 points, n=30) and moderate (MMSE < 21 points, n=17) AD. In the whole patient sample, the agreement with the FDG-PET finding was 77% (chance-corrected kappa [κ]=0.34, p=0.016) for t-tau, 68% (κ=0.10, n.s.) for p-tau181, and 68% (κ=0.04, n.s.) for Aβ1-42. No significant agreement was found in the mild AD subgroup, while there was a strong agreement for t-tau (94%, κ=0.77, p=0.001) and p-tau181 (88%, κ=0.60, p=0.014) in the moderate AD group. A significant agreement between the FDG-PET and CSF tau findings in patients with AD supports the view that both are markers of neurodegeneration. CSF tau proteins and FDG-PET might substitute each other as supportive diagnostic tools in patients with suspected moderate-to-severe Alzheimer's dementia, while this is not the case in subjects at an earlier disease stage. PMID:22044023

  15. Reference Cluster Normalization Improves Detection of Frontotemporal Lobar Degeneration by Means of FDG-PET

    PubMed Central

    Dukart, Juergen; Perneczky, Robert; Förster, Stefan; Barthel, Henryk; Diehl-Schmid, Janine; Draganski, Bogdan; Obrig, Hellmuth; Santarnecchi, Emiliano; Drzezga, Alexander; Fellgiebel, Andreas; Frackowiak, Richard; Kurz, Alexander; Müller, Karsten; Sabri, Osama; Schroeter, Matthias L.; Yakushev, Igor

    2013-01-01

    Positron emission tomography with [18F] fluorodeoxyglucose (FDG-PET) plays a well-established role in assisting early detection of frontotemporal lobar degeneration (FTLD). Here, we examined the impact of intensity normalization to different reference areas on accuracy of FDG-PET to discriminate between patients with mild FTLD and healthy elderly subjects. FDG-PET was conducted at two centers using different acquisition protocols: 41 FTLD patients and 42 controls were studied at center 1, 11 FTLD patients and 13 controls were studied at center 2. All PET images were intensity normalized to the cerebellum, primary sensorimotor cortex (SMC), cerebral global mean (CGM), and a reference cluster with most preserved FDG uptake in the aforementioned patients group of center 1. Metabolic deficits in the patient group at center 1 appeared 1.5, 3.6, and 4.6 times greater in spatial extent, when tracer uptake was normalized to the reference cluster rather than to the cerebellum, SMC, and CGM, respectively. Logistic regression analyses based on normalized values from FTLD-typical regions showed that at center 1, cerebellar, SMC, CGM, and cluster normalizations differentiated patients from controls with accuracies of 86%, 76%, 75% and 90%, respectively. A similar order of effects was found at center 2. Cluster normalization leads to a significant increase of statistical power in detecting early FTLD-associated metabolic deficits. The established FTLD-specific cluster can be used to improve detection of FTLD on a single case basis at independent centers – a decisive step towards early diagnosis and prediction of FTLD syndromes enabling specific therapies in the future. PMID:23451025

  16. Reference cluster normalization improves detection of frontotemporal lobar degeneration by means of FDG-PET.

    PubMed

    Dukart, Juergen; Perneczky, Robert; Förster, Stefan; Barthel, Henryk; Diehl-Schmid, Janine; Draganski, Bogdan; Obrig, Hellmuth; Santarnecchi, Emiliano; Drzezga, Alexander; Fellgiebel, Andreas; Frackowiak, Richard; Kurz, Alexander; Müller, Karsten; Sabri, Osama; Schroeter, Matthias L; Yakushev, Igor

    2013-01-01

    Positron emission tomography with [18F] fluorodeoxyglucose (FDG-PET) plays a well-established role in assisting early detection of frontotemporal lobar degeneration (FTLD). Here, we examined the impact of intensity normalization to different reference areas on accuracy of FDG-PET to discriminate between patients with mild FTLD and healthy elderly subjects. FDG-PET was conducted at two centers using different acquisition protocols: 41 FTLD patients and 42 controls were studied at center 1, 11 FTLD patients and 13 controls were studied at center 2. All PET images were intensity normalized to the cerebellum, primary sensorimotor cortex (SMC), cerebral global mean (CGM), and a reference cluster with most preserved FDG uptake in the aforementioned patients group of center 1. Metabolic deficits in the patient group at center 1 appeared 1.5, 3.6, and 4.6 times greater in spatial extent, when tracer uptake was normalized to the reference cluster rather than to the cerebellum, SMC, and CGM, respectively. Logistic regression analyses based on normalized values from FTLD-typical regions showed that at center 1, cerebellar, SMC, CGM, and cluster normalizations differentiated patients from controls with accuracies of 86%, 76%, 75% and 90%, respectively. A similar order of effects was found at center 2. Cluster normalization leads to a significant increase of statistical power in detecting early FTLD-associated metabolic deficits. The established FTLD-specific cluster can be used to improve detection of FTLD on a single case basis at independent centers - a decisive step towards early diagnosis and prediction of FTLD syndromes enabling specific therapies in the future. PMID:23451025

  17. "Bottle Brush Sign"-Spinal Meningeal Disease on 18F-FDG PET-CT Scan.

    PubMed

    Riaz, Saima; Naz, Fozia; Bashir, Humayun; Niazi, Imran Khalid

    2016-09-01

    A 30-year-old man with a history of stage IV AE diffuse large cell lymphoma of left proximal humerus presented with new onset lower limb weakness at completion of chemotherapy. The F-FDG PET-CT scan showed increased intraspinal uptake from T12 to S1 vertebrae with unique "bottle brush" appearance in keeping with spinal meningeal disease. The leptomeningeal disease was further confirmed on correlative MRI scan. PMID:27405033

  18. Diagnostic utility of FDG-PET in neurolymphomatosis: report of five cases.

    PubMed

    Kinoshita, Hisanori; Yamakado, Hodaka; Kitano, Toshiyuki; Kitamura, Akihiro; Yamashita, Hirofumi; Miyamoto, Masakazu; Hitomi, Takefumi; Okada, Tomohisa; Nakamoto, Yuji; Sawamoto, Nobukatsu; Takaori-Kondo, Akifumi; Takahashi, Ryosuke

    2016-09-01

    Neurolymphomatosis (NL) is a rare condition involving the infiltration of lymphoma cells into the peripheral nervous system. NL can be primary or secondary in the setting of an unknown or known hematologic malignancy, respectively. Here, we report five cases in which F-18 2-fluoro-2-deoxy-glucose positron emission tomography/computed tomography (F-18 FDG-PET/CT) had great value for diagnosing NL. Two cases were rare primary NL, and the other three were secondary NL. Clinical presentations were asymmetric sensorimotor disturbances in the extremities with or without involvement of cranial nerves. Furthermore, all patients experienced spontaneous pain in the face or affected extremities. Cerebrospinal fluid analysis was cytologically negative in two of five cases. Gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) detected abnormalities in the cranial nerves, nerve roots, and cauda equina in all cases except case 1 and the recurrent stage of case 2. F-18 FDG-PET/CT showed clear visualization of almost all the lymphomatous involvement of peripheral nerves and other tissues in all patients. Furthermore, F-18 FDG-PET/CT detected abnormalities including asymptomatic lesions that were not detected with MRI, and also identified the appropriate lesion for diagnostic biopsy. However, as in case 3, the lesions in the left oculomotor nerve and the cauda equina were detected only with Gd-enhanced MRI, which has superior spatial resolution. In conclusion, F-18 FDG-PET/CT is a sensitive modality that can suggest the presence of malignancy and identify appropriate places for diagnostic biopsies. It is especially useful when combined with Gd-enhanced MRI, even in patients with primary NL that is usually difficult to diagnose. PMID:27286845

  19. (18)F-FDG PET/CT findings in a case with HIV (-) Kaposi sarcoma.

    PubMed

    Ozdemir, E; Poyraz, N Y; Keskin, M; Kandemir, Z; Turkolmez, S

    2014-01-01

    Although mucocutaneous sites are the most frequently encountered sites of involvement, Kaposi Sarcoma (KS) may also occasionally involve the breast and the skeletal, endocrine, urinary and nervous systems.. Various imaging modalities may be used to delineate the extent of the disease by detecting unexpected sites of involvement. Herein, we report a case of classical type KS, in whom staging with (18)F-FDG PET/CT imaging disclosed widespread disease and unexpected findings of bone and salivary gland involvement. PMID:24119549

  20. FDG PET/CT diagnosis of hepatic lymphoma mimicking focal fatty infiltration on CT

    PubMed Central

    Lin, Eugene; Lee, Marie; Agoff, Nicholas

    2010-01-01

    Areas of hypoattenuation in the liver which do not have mass effect are typically thought to represent focal fatty infiltration. Rarely, tumors can present without mass effect in the liver. We present a case in which areas of liver hypoattenuation which were initially thought to represent focal fatty infiltration on CT due to lack of mass effect had abnormal uptake on a FDG PET/CT exam; these areas were due to secondary hepatic involvement from non-Hodgkin’s lymphoma. PMID:22470725

  1. Zosteriform Secondary Cutaneous Diffuse Large B-Cell Lymphoma on FDG PET/CT.

    PubMed

    Liao, Chiung-Wei; Yen, Kuo-Yang; Hsieh, Te-Chun; Kao, Chia-Hung

    2016-09-01

    We present a case of a woman who had erythematous papules on the abdomen accompanied with numbness and local heat sensation. She had received chemotherapy for advanced follicular lymphoma. F-FDG PET/CT demonstrated band-like hypermetabolic lesions seemingly involving dermatomes of lower abdominal wall, which was confirmed as secondary cutaneous diffuse large B-cell lymphoma via skin biopsy. PMID:27405036

  2. Primary Pulmonary Artery Sarcoma on Dual-Time Point FDG PET/CT Imaging.

    PubMed

    Li, Juan; Zhao, Qian; He, Lirong; Zhuang, Xiaoqing; Li, Fang

    2016-08-01

    A 59-year-old man presented cough, chest pain, and shortness of breath for 2 weeks and fever for 4 days. A contrast chest CT revealed a large right pulmonary artery filling defect, suggestive of pulmonary embolism that failed to respond to anticoagulation therapy. FDG PET/CT was performed to evaluate possible malignancy, which revealed intense activity in the right main pulmonary artery without any extrathoracic abnormality. The ratio of the SUVmax of this lesion to the liver was significantly increased in the delayed PET images. The pathological examination demonstrated primary pulmonary artery sarcoma. PMID:27163460

  3. Grover disease (transient acantholytic dermatosis) in acute myeloid leukemia on FDG PET/CT.

    PubMed

    Zhu, Hongyun June; Clark, Lindsey N; Deloney, Linda A; McDonald, James E

    2014-02-01

    A 48-year-old man with a newly diagnosed acute myeloid leukemia developed purpuric rash on day 6 after chemotherapy. Skin biopsy on day 8 demonstrated Grover disease. Triamcinolone treatment started on day 10 with subjective improvement on day 15. Initial FDG PET/CT on day 12 demonstrated rarely seen diffuse skin uptake that was interpreted as technical artifact and repeated on day 16. Accurately reviewing both PET and CT imaging would prevent confusion between diffuse cutaneous hypermetabolic activity and a technical artifact. Grover disease usually affects the trunk and may be related to the elimination of chemotherapy agents by sweating. PMID:24152615

  4. 18F-FDG PET/CT Findings of Scrub Typhus.

    PubMed

    Kim, Jahae; Kwon, Seong Young; Kang, Sae-Ryung; Cho, Sang-Geon; Song, Ho-Chun

    2015-10-01

    Scrub typhus is an acute infectious disease caused by Orienta tsutsugamushi, which is clinically manifested by fever, generalized lymphadenopathy, diffuse myalgia, headache, maculopapular rash, and eschars at the site of chigger feedings. Diagnosis of scrub typhus requires compatible clinical features, history of exposure, and result of selorogic testing. In recent years, F-FDG PET/CT is seen as having increasing potential for use in examination and management of patients with infectious or inflammatory disorders. This is a PET/CT case demonstrating scrub typhus in a patient without evidence of recurrence of thyroid papillary cancer. PMID:26098289

  5. 18F-FDG PET/CT in Neurolymphomatosis: Report of 3 Cases

    PubMed Central

    Canh, Nguyen Xuan; Tan, Ngo Van; Tung, Tran Thanh; Son, Nguyen Truong; Maurea, Simone

    2014-01-01

    Neurolymphomatosis is a rare manifestation of non-Hodgkin lymphoma characterized by infiltration of peripheral nerves, nerve roots, plexus and cranial nerves by malignant lymphocytes. This report presents positron emission tomography/computed tomography (PET/CT)imaging with 2-deoxy-2-18F-fluoro-D-glucose (18F-FDG) in 3 cases of non-Hodgkin lymphoma with nerve infiltration, including one newly diagnosed lymphoma, one recurrent lymphoma in previous nerve lesions and one newly recurrent lymphoma. PET/CT could reveal the affected neural structures including cranial nerves, spinal nerve roots, brachial plexus, cervicothoracic ganglion, intercostal nerves, branches of the vagus nerve, lumbosacral plexus and sciatic nerves. There was relative concordance between PET/CT and MRI in detection of affected cranial nerves. PET/CT seemed to be better than MRI in detection of affected peripheral nerves. 18F-FDG PET/CT was a whole-body imaging technique with the ability to reveal the affected cranial nerves, peripheral nerves, nerve roots and plexus in non-Hodgkin lymphoma. A thorough understanding of disease and use of advanced imaging modalities will increasingly detect neurolymphomatosis.

  6. A new assessment model for tumor heterogeneity analysis with [18]F-FDG PET images

    PubMed Central

    Wang, Ping; Xu, Wengui; Sun, Jian; Yang, Chengwen; Wang, Gang; Sa, Yu; Hu, Xin-Hua; Feng, Yuanming

    2016-01-01

    It has been shown that the intratumor heterogeneity can be characterized with quantitative analysis of the [18]F-FDG PET image data. The existing models employ multiple parameters for feature extraction which makes it difficult to implement in clinical settings for the quantitative characterization. This article reports an easy-to-use and differential SUV based model for quantitative assessment of the intratumor heterogeneity from 3D [18]F-FDG PET image data. An H index is defined to assess tumor heterogeneity by summing voxel-wise distribution of differential SUV from the [18]F-FDG PET image data. The summation is weighted by the distance of SUV difference among neighboring voxels from the center of the tumor and can thus yield increased values for tumors with peripheral sub-regions of high SUV that often serves as an indicator of augmented malignancy. Furthermore, the sign of H index is used to differentiate the rate of change for volume averaged SUV from its center to periphery. The new model with the H index has been compared with a widely-used model of gray level co-occurrence matrix (GLCM) for image texture characterization with phantoms of different configurations and the [18]F-FDG PET image data of 6 lung cancer patients to evaluate its effectiveness and feasibility for clinical uses. The comparison of the H index and GLCM parameters with the phantoms demonstrate that the H index can characterize the SUV heterogeneity in all of 6 2D phantoms while only 1 GLCM parameter can do for 1 and fail to differentiate for other 2D phantoms. For the 8 3D phantoms, the H index can clearly differentiate all of them while the 4 GLCM parameters provide complicated patterns in the characterization. Feasibility study with the PET image data from 6 lung cancer patients show that the H index provides an effective single-parameter metric to characterize tumor heterogeneity in terms of the local SUV variation, and it has higher correlation with tumor volume change after

  7. [A Case of Metastatic Seminomatous Testicular Tumor with Complicated Diagnosis by FDG-PET].

    PubMed

    Hashizume, Akihito; Mizuno, Nobuhiko; Kawai, Masaki; Kishida, Takeshi

    2016-07-01

    18F-fluorodeoxy glucose positron emission tomography (FDG-PET) for evaluation of the post chemotherapy residual tumor of the seminomatous testicular germ cell tumor is recommended by several guidelines. We report a case whose residual tumor was evaluated by FDG PET but the results were difficult to interpret. A 41-year-old male with left seminomatous germ cell tumor of the testis and 60 mm retroperitoneal lymph node (RPLN) metastasis was referred to our hospital. The International Germ Cell Consensus Classification (IGCCC) was good prognosis. After high orchiectomy, three cycles of bleomycin, etoposide, and cisplatin (BEP) chemotherapy normalized the tumor marker and the RPLN decreased to 15 mm. The standardized uptake value (SUV) max at the RPLN by FDG-PET was 2.93. Although residual viable cells were suspected, the SUV max was relatively low. Thus surveillance without additional therapy was selected. After observation for 25 weeks, the tumor grew to 25 mm. Then four cycles of paclitaxel, ifosfamide, and cisplatin (TIP) chemotherapy were indicated for the recurrence. The RPLN was decreased to 15 mm, but the SUV max was still as high as 2.67 at 6 weeks after the last chemotherapy. We dissected the residual tumor suspecting viable cancer, but the pathological examination revealed necrotic tissue without any viable cells. He has had no signs of recurrence for 1 year and 9 months after the operation. PMID:27569358

  8. F-18-FDG-PET Confined Radiotherapy of Locally Advanced NSCLC With Concomitant Chemotherapy: Results of the PET-PLAN Pilot Trial

    SciTech Connect

    Fleckenstein, Jochen; Hellwig, Dirk; Kremp, Stephanie; Grgic, Aleksandar; Groeschel, Andreas; Kirsch, Carl-Martin; Nestle, Ursula; Ruebe, Christian

    2011-11-15

    Purpose: The integration of fluoro-deoxy-D-glucose positron emission tomography (FDG-PET) in the process of radiotherapy (RT) planning of locally advanced non-small-cell lung cancer (NSCLC) may improve diagnostic accuracy and minimize interobserver variability compared with target volume definition solely based on computed tomography. Furthermore, irradiating only FDG-PET-positive findings and omitting elective nodal regions may allow dose escalation by treating smaller volumes. The aim of this prospective pilot trial was to evaluate the therapeutic safety of FDG-PET-based RT treatment planning with an autocontour-derived delineation of the primary tumor. Methods and Materials: Eligible patients had Stages II-III inoperable NSCLC, and simultaneous, platinum-based radiochemotherapy was indicated. FDG-PET and computed tomography acquisitions in RT treatment planning position were coregistered. The clinical target volume (CTV) included the FDG-PET-defined primary tumor, which was autodelineated with a source-to-background algorithm, plus FDG-PET-positive lymph node stations. Limited by dose restrictions for normal tissues, prescribed total doses were in the range of 66.6 to 73.8 Gy. The primary endpoint was the rate of out-of-field isolated nodal recurrences (INR). Results: As per intent to treat, 32 patients received radiochemotherapy. In 15 of these patients, dose escalation above 66.6 Gy was achieved. No Grade 4 toxicities occurred. After a median follow-up time of 27.2 months, the estimated median survival time was 19.3 months. During the observation period, one INR was observed in 23 evaluable patients. Conclusions: FDG-PET-confined target volume definition in radiochemotherapy of NSCLC, based on a contrast-oriented source-to-background algorithm, was associated with a low risk of INR. It might provide improved tumor control because of dose escalation.

  9. Correlation of {sup 18}F-FDG Avid Volumes on Pre–Radiation Therapy and Post–Radiation Therapy FDG PET Scans in Recurrent Lung Cancer

    SciTech Connect

    Shusharina, Nadya Cho, Joseph; Sharp, Gregory C.; Choi, Noah C.

    2014-05-01

    Purpose: To investigate the spatial correlation between high uptake regions of 2-deoxy-2-[{sup 18}F]-fluoro-D-glucose positron emission tomography ({sup 18}F-FDG PET) before and after therapy in recurrent lung cancer. Methods and Materials: We enrolled 106 patients with inoperable lung cancer into a prospective study whose primary objectives were to determine first, the earliest time point when the maximum decrease in FDG uptake representing the maximum metabolic response (MMR) is attainable and second, the optimum cutoff value of MMR based on its predicted tumor control probability, sensitivity, and specificity. Of those patients, 61 completed the required 4 serial {sup 18}F-FDG PET examinations after therapy. Nineteen of 61 patients experienced local recurrence at the primary tumor and underwent analysis. The volumes of interest (VOI) on pretherapy FDG-PET were defined by use of an isocontour at ≥50% of maximum standard uptake value (SUV{sub max}) (≥50% of SUV{sub max}) with correction for heterogeneity. The VOI on posttherapy images were defined at ≥80% of SUV{sub max}. The VOI of pretherapy and posttherapy {sup 18}F-FDG PET images were correlated for the extent of overlap. Results: The size of VOI at pretherapy images was on average 25.7% (range, 8.8%-56.3%) of the pretherapy primary gross tumor volume (GTV), and their overlap fractions were 0.8 (95% confidence interval [CI]: 0.7-0.9), 0.63 (95% CI: 0.49-0.77), and 0.38 (95% CI: 0.19-0.57) of VOI of posttherapy FDG PET images at 10 days, 3 months, and 6 months, respectively. The residual uptake originated from the pretherapy VOI in 15 of 17 cases. Conclusions: VOI defined by the SUV{sub max}-≥50% isocontour may be a biological target volume for escalated radiation dose.

  10. FDG-PET/CT in the Assessment of Treatment Response after Oncologic Treatment of Head and Neck Squamous Cell Carcinoma

    PubMed Central

    Keski-Säntti, Harri; Mustonen, Timo; Schildt, Jukka; Saarilahti, Kauko; Mäkitie, Antti A

    2014-01-01

    BACKGROUND In many centers, 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) is used to monitor treatment response after definitive (chemo)radiotherapy [(C)RT] for head and neck squamous cell carcinoma (HNSCC), but its usefulness remains somewhat controversial. We aimed at assessing the accuracy of FDG-PET/CT in detecting residual disease after (C)RT. METHOD All HNSCC patients with FDG-PET/CT performed to assess treatment response 10–18 weeks after definitive (C)RT at our institution during 2008–2010 were included. The patient charts were reviewed for FDG-PET/CT findings, histopathologic findings, and follow-up data. The median follow-up time for FDG-PET/CT negative patients was 26 months. RESULTS Eighty-eight eligible patients were identified. The stage distribution was as follows: I, n = 1; II, n = 15; III, n = 17; IV, n = 55. The negative predictive value, positive predictive value, specificity, sensitivity, and accuracy of FDG-PET/CT in detecting residual disease were 87%, 81%, 94%, 65%, and 85%, respectively. The corresponding specific figures for the primary tumor site were 91%, 71%, 94%, 59%, and 86% and for the neck 93%, 100%, 100%, 75%, and 94%, respectively. CONCLUSIONS In patients who have received definitive (C)RT for HNSCC, post-treatment FDG-PET/CT has good potential to guide clinical decision-making. Patients with negative scan can safely be followed up clinically only, while positive scan necessitates tissue biopsies or a neck dissection to rule out residual disease. PMID:25210484