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Sample records for 2-deoxy-2-f-18fluoro-d-glucose-positron emission tomography

  1. A case of dedifferentiated liposarcoma showing a biphasic pattern on 2-deoxy-2-F18- fluoro-D-glucose positron emission tomography/ computed tomography

    Directory of Open Access Journals (Sweden)

    Manabu Hoshi

    2013-04-01

    Full Text Available Integrated 2-deoxy-2-F18-fluoro-D-glucose positron emission tomography combined with computed tomography (FDG-PET/CT has been used in the field of soft tissue sarcoma. We report an 81-year-old man with dedifferentiated liposarcoma in the left thigh, which was composed of well-differentiated liposarcoma and pleomorphic malignant fibrous histiocytoma. As well as other radiological modalities, FDG-PET was able to demonstrate a biphasic signal pattern composed of well-differentiated liposarcoma and dedifferentiated area, being consistent with the histological grade of malignancy.

  2. Positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Muehllehner, Gerd; Karp, Joel S [Department of Radiology, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104 (United States)

    2006-07-07

    The developments in positron emission tomography (PET) are reviewed with an emphasis on instrumentation for clinical PET imaging. After a brief summary of positron imaging before the advent of computed tomography, various improvements are highlighted including the move from PET scanners with septa to fully 3D scanners, changes in the preferred scintillators, efforts to improve the energy discrimination, and improvements in attenuation correction. Time-of-flight PET imaging is given special attention due to the recent revival of this technique, which promises significant improvement. Besides technical instrumentation efforts, other factors which influenced the acceptance of clinical PET are also discussed. (review)

  3. Positron Emission Tomography (PET)

    Energy Technology Data Exchange (ETDEWEB)

    Welch, M.J.

    1990-01-01

    Positron emission tomography (PET) assesses biochemical processes in the living subject, producing images of function rather than form. Using PET, physicians are able to obtain not the anatomical information provided by other medical imaging techniques, but pictures of physiological activity. In metaphoric terms, traditional imaging methods supply a map of the body's roadways, its, anatomy; PET shows the traffic along those paths, its biochemistry. This document discusses the principles of PET, the radiopharmaceuticals in PET, PET research, clinical applications of PET, the cost of PET, training of individuals for PET, the role of the United States Department of Energy in PET, and the futures of PET. 22 figs.

  4. Positron Emission Tomography (PET)

    Science.gov (United States)

    Welch, M. J.

    1990-01-01

    Positron emission tomography (PET) assesses biochemical processes in the living subject, producing images of function rather than form. Using PET, physicians are able to obtain not the anatomical information provided by other medical imaging techniques, but pictures of physiological activity. In metaphoric terms, traditional imaging methods supply a map of the body's roadways, its, anatomy; PET shows the traffic along those paths, its biochemistry. This document discusses the principles of PET, the radiopharmaceuticals in PET, PET research, clinical applications of PET, the cost of PET, training of individuals for PET, the role of the United States Department of Energy in PET, and the futures of PET.

  5. Positron emission tomography

    CERN Document Server

    Paans, A M J

    2006-01-01

    Positron Emission Tomography (PET) is a method for measuring biochemical and physiological processes in vivo in a quantitative way by using radiopharmaceuticals labelled with positron emitting radionuclides such as 11C, 13N, 15O and 18F and by measuring the annihilation radiation using a coincidence technique. This includes also the measurement of the pharmacokinetics of labelled drugs and the measurement of the effects of drugs on metabolism. Also deviations of normal metabolism can be measured and insight into biological processes responsible for diseases can be obtained. At present the combined PET/CT scanner is the most frequently used scanner for whole-body scanning in the field of oncology.

  6. NMF on positron emission tomography

    DEFF Research Database (Denmark)

    Bödvarsson, Bjarni; Hansen, Lars Kai; Svarer, Claus;

    2007-01-01

    In positron emission tomography, kinetic modelling of brain tracer uptake, metabolism or binding requires knowledge of the cerebral input function. Traditionally, this is achieved with arterial blood sampling in the arm or as shown in (Liptrot, M, et al., 2004) by non-invasive K-means clustering....... We propose another method to estimate time-activity curves (TAC) extracted directly from dynamic positron emission tomography (PET) scans by non-negative matrix factorization (NMF). Since the scaling of the basis curves is lost in the NMF the estimated TAC is scaled by a vector alpha which...

  7. Positron emission tomography basic sciences

    CERN Document Server

    Townsend, D W; Valk, P E; Maisey, M N

    2003-01-01

    Essential for students, science and medical graduates who want to understand the basic science of Positron Emission Tomography (PET), this book describes the physics, chemistry, technology and overview of the clinical uses behind the science of PET and the imaging techniques it uses. In recent years, PET has moved from high-end research imaging tool used by the highly specialized to an essential component of clinical evaluation in the clinic, especially in cancer management. Previously being the realm of scientists, this book explains PET instrumentation, radiochemistry, PET data acquisition and image formation, integration of structural and functional images, radiation dosimetry and protection, and applications in dedicated areas such as drug development, oncology, and gene expression imaging. The technologist, the science, engineering or chemistry graduate seeking further detailed information about PET, or the medical advanced trainee wishing to gain insight into the basic science of PET will find this book...

  8. Radiopharmaceutical chemistry for positron emission tomography

    NARCIS (Netherlands)

    Elsinga, PH

    2002-01-01

    Radiopharmaceutical chemistry includes the selection, preparation, and preclinical evaluation of radiolabeled compounds. This paper describes selection criteria for candidates for positron emission tomography (PET) investigations. Practical aspects of nucleophilic and electrophilic F-18-fluorination

  9. Data analysis in emission tomography using emission-count posteriors

    Science.gov (United States)

    Sitek, Arkadiusz

    2012-11-01

    A novel approach to the analysis of emission tomography data using the posterior probability of the number of emissions per voxel (emission count) conditioned on acquired tomographic data is explored. The posterior is derived from the prior and the Poisson likelihood of the emission-count data by marginalizing voxel activities. Based on emission-count posteriors, examples of Bayesian analysis including estimation and classification tasks in emission tomography are provided. The application of the method to computer simulations of 2D tomography is demonstrated. In particular, the minimum-mean-square-error point estimator of the emission count is demonstrated. The process of finding this estimator can be considered as a tomographic image reconstruction technique since the estimates of the number of emissions per voxel divided by voxel sensitivities and acquisition time are the estimates of the voxel activities. As an example of a classification task, a hypothesis stating that some region of interest (ROI) emitted at least or at most r-times the number of events in some other ROI is tested. The ROIs are specified by the user. The analysis described in this work provides new quantitative statistical measures that can be used in decision making in diagnostic imaging using emission tomography.

  10. Advanced Instrumentation for Positron Emission Tomography [PET

    Science.gov (United States)

    Derenzo, S. E.; Budinger, T. F.

    1985-04-01

    This paper summarizes the physical processes and medical science goals that underlay modern instrumentation design for Positron Emission Tomography. The paper discusses design factors such as detector material, crystalphototube coupling, shielding geometry, sampling motion, electronics design, time-of-flight, and the interrelationships with quantitative accuracy, spatial resolution, temporal resolution, maximum data rates, and cost.

  11. Is positron emission tomography useful in stroke?

    NARCIS (Netherlands)

    DeReuck, J; Leys, D; DeKeyser, J

    1997-01-01

    Positron emission tomography (PET) has been widely used in the study of stroke and related cerebrovascular diseases. It has shown the various stages leading to cerebral infarction and defined the significance of the ischaemic penumbra. PET scan can predict the clinical outcome of patients with acute

  12. 4D image reconstruction for emission tomography

    Science.gov (United States)

    Reader, Andrew J.; Verhaeghe, Jeroen

    2014-11-01

    An overview of the theory of 4D image reconstruction for emission tomography is given along with a review of the current state of the art, covering both positron emission tomography and single photon emission computed tomography (SPECT). By viewing 4D image reconstruction as a matter of either linear or non-linear parameter estimation for a set of spatiotemporal functions chosen to approximately represent the radiotracer distribution, the areas of so-called ‘fully 4D’ image reconstruction and ‘direct kinetic parameter estimation’ are unified within a common framework. Many choices of linear and non-linear parameterization of these functions are considered (including the important case where the parameters have direct biological meaning), along with a review of the algorithms which are able to estimate these often non-linear parameters from emission tomography data. The other crucial components to image reconstruction (the objective function, the system model and the raw data format) are also covered, but in less detail due to the relatively straightforward extension from their corresponding components in conventional 3D image reconstruction. The key unifying concept is that maximum likelihood or maximum a posteriori (MAP) estimation of either linear or non-linear model parameters can be achieved in image space after carrying out a conventional expectation maximization (EM) update of the dynamic image series, using a Kullback-Leibler distance metric (comparing the modeled image values with the EM image values), to optimize the desired parameters. For MAP, an image-space penalty for regularization purposes is required. The benefits of 4D and direct reconstruction reported in the literature are reviewed, and furthermore demonstrated with simple simulation examples. It is clear that the future of reconstructing dynamic or functional emission tomography images, which often exhibit high levels of spatially correlated noise, should ideally exploit these 4D

  13. A wavelet phase filter for emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, E.T.; Lin, B. [Illinois Inst. of Tech., Chicago, IL (United States). Dept. of Mathematics

    1995-07-01

    The presence of a high level of noise is a characteristic in some tomographic imaging techniques such as positron emission tomography (PET). Wavelet methods can smooth out noise while preserving significant features of images. Mallat et al. proposed a wavelet based denoising scheme exploiting wavelet modulus maxima, but the scheme is sensitive to noise. In this study, the authors explore the properties of wavelet phase, with a focus on reconstruction of emission tomography images. Specifically, they show that the wavelet phase of regular Poisson noise under a Haar-type wavelet transform converges in distribution to a random variable uniformly distributed on [0, 2{pi}). They then propose three wavelet-phase-based denoising schemes which exploit this property: edge tracking, local phase variance thresholding, and scale phase variation thresholding. Some numerical results are also presented. The numerical experiments indicate that wavelet phase techniques show promise for wavelet based denoising methods.

  14. Development of novel emission tomography system

    Science.gov (United States)

    Fu, Geng

    In recent years, small animals, such as mice and rats, have been widely used as subjects of study in biomedical research while molecular biology and imaging techniques open new opportunities to investigate disease model. With the help of medical imaging techniques, researchers can investigate underlying mechanisms inside the small animal, which are useful for both early diagnosis and treatment monitoring. Based on tracer principle single photon emission computed tomography (SPECT) has increased popularity in small animal imaging due to its higher spatial resolution and variety of single-photon emitting radionuclides. Since the image quality strongly depends on the detector properties, both scintillation and semiconductor detectors are under active investigation for high resolution X-ray and gamma ray photon detection. The desired detector properties include high intrinsic spatial resolution, high energy resolution, and high detection efficiency. In this thesis study, we have made extensive efforts to develop novel emission tomography system, and evaluate the use of both semiconductor and ultra-high resolution scintillation detectors for small animal imaging. This thesis work includes the following three areas. Firstly, we have developed a novel energy-resolved photon counting (ERPC) detector. With the benefits of high energy resolution, high spatial resolution, flexible detection area, and a wide dynamic range of 27--200keV, ERPC detector is well-suited for small animal SPECT applications. For prototype ERPC detector excellent imaging (˜350microm) and spectroscopic performance (4keV Co-57 122keV) has been demonstrated in preliminary study. Secondly, to further improve spatial resolution to hundred-micron level, an ultra-high resolution Intensified EMCCD (I-EMCCD) detector has been designed and evaluated. This detector consists of the newly developed electron multiplying CCD (EMCCD) sensor, columnar CsI(Tl) scintillator, and an electrostatic de-magnifier (DM) tube

  15. Therapy response evaluation with positron emission tomography-computed tomography.

    Science.gov (United States)

    Segall, George M

    2010-12-01

    Positron emission tomography-computed tomography with F-18-fluorodeoxyglucose is widely used for evaluation of therapy response in patients with solid tumors but has not been as readily adopted in clinical trials because of the variability of acquisition and processing protocols and the absence of universal response criteria. Criteria proposed for clinical trials are difficult to apply in clinical practice, and gestalt impression is probably accurate in individual patients, especially with respect to the presence of progressive disease and complete response. Semiquantitative methods of determining tissue glucose metabolism, such as standard uptake value, can be a useful descriptor for levels of tissue glucose metabolism and changes in response to therapy if technical quality control measures are carefully maintained. The terms partial response, complete response, and progressive disease are best used in clinical trials in which the terms have specific meanings and precise definitions. In clinical practice, it may be better to use descriptive terminology agreed upon by imaging physicians and clinicians in their own practice.

  16. 89Zr radiochemistry for positron emission tomography.

    Science.gov (United States)

    Severin, Gregory W; Engle, Jonathan W; Barnhart, Todd E; Nickles, R Jerry

    2011-09-01

    The positron emitting isotope (89)Zr is an ideal radionuclide for use in positron emission tomography (PET) imaging with monoclonal antibodies (mAbs). This article reviews the cyclotron physics of (89)Zr production, and the chemical separation methods for isolating it from yttrium target material. (89)Zr coordination with the bifunctional chelate desferrioxamine B is discussed, along with the common procedures for attaching the chelate to mAbs. The review is intended to detail the procedure for creating (89)Zr labeled mAbs, going from cyclotron to PET.

  17. Positron Emission Tomography: Its 65 years

    Science.gov (United States)

    Del Guerra, A.; Belcari, N.; Bisogni, M.

    2016-04-01

    Positron Emission Tomography (PET) is a well-established imaging technique for in vivo molecular imaging. In this review after a brief history of PET there are presented its physical principles and the technology that has been developed for bringing PET from a bench experiment to a clinical indispensable instrument. The limitations and performance of the PET tomographs are discussed, both as for the hardware and software aspects. The status of art of clinical, pre-clinical and hybrid scanners (, PET/CT and PET/MR) is reported. Finally the actual trend and the recent and future technological developments are fully illustrated.

  18. Estimation of linear functionals in emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kuruc, A.

    1995-08-01

    In emission tomography, the spatial distribution of a radioactive tracer is estimated from a finite sample of externally-detected photons. We present an algorithm-independent theory of statistical accuracy attainable in emission tomography that makes minimal assumptions about the underlying image. Let f denote the tracer density as a function of position (i.e., f is the image being estimated). We consider the problem of estimating the linear functional {Phi}(f) {triple_bond} {integral}{phi}(x)f(x) dx, where {phi} is a smooth function, from n independent observations identically distributed according to the Radon transform of f. Assuming only that f is bounded above and below away from 0, we construct statistically efficient estimators for {Phi}(f). By definition, the variance of the efficient estimator is a best-possible lower bound (depending on and f) on the variance of unbiased estimators of {Phi}(f). Our results show that, in general, the efficient estimator will have a smaller variance than the standard estimator based on the filtered-backprojection reconstruction algorithm. The improvement in performance is obtained by exploiting the range properties of the Radon transform.

  19. Positron Emission Tomography of the Heart

    Science.gov (United States)

    Schelbert, H. R.; Phelps, M. E.; Kuhl, D. E.

    1979-01-01

    Positron emission computed tomography (PCT) represents an important new tool for the noninvasive evaluation and, more importantly, quantification of myocardial performance. Most currently available techniques permit assessment of only one aspect of cardiac function, i.e., myocardial perfusion by gamma scintillation camera imaging with Thallium-201 or left ventricular function by echocardiography or radionuclide angiocardiography. With PCT it may become possible to study all three major segments of myocardial performance, i.e., regional blood flow, mechanical function and, most importantly, myocardial metabolism. Each of these segments can either be evaluated separately or in combination. This report briefly describes the principles and technological advantages of the imaging device, reviews currently available radioactive tracers and how they can be employed for the assessment of flow, function and metabolism; and, lastly, discusses possible applications of PCT for the study of cardiac physiology or its potential role in the diagnosis of cardiac disease.

  20. Motion correction in thoracic positron emission tomography

    CERN Document Server

    Gigengack, Fabian; Dawood, Mohammad; Schäfers, Klaus P

    2015-01-01

    Respiratory and cardiac motion leads to image degradation in Positron Emission Tomography (PET), which impairs quantification. In this book, the authors present approaches to motion estimation and motion correction in thoracic PET. The approaches for motion estimation are based on dual gating and mass-preserving image registration (VAMPIRE) and mass-preserving optical flow (MPOF). With mass-preservation, image intensity modulations caused by highly non-rigid cardiac motion are accounted for. Within the image registration framework different data terms, different variants of regularization and parametric and non-parametric motion models are examined. Within the optical flow framework, different data terms and further non-quadratic penalization are also discussed. The approaches for motion correction particularly focus on pipelines in dual gated PET. A quantitative evaluation of the proposed approaches is performed on software phantom data with accompanied ground-truth motion information. Further, clinical appl...

  1. Positron emission tomography of the heart

    Energy Technology Data Exchange (ETDEWEB)

    Schelbert, H.R.; Phelps, M.E.; Kuhl, D.E.

    1979-01-01

    Positron emission computed tomography (PCT) represents an important new tool for the noninvasive evaluation and, more importantly, quantification of myocardial performance. Most currently available techniques permit assessment of only one aspect of cardiac function, i.e., myocardial perfusion by gamma scintillation camera imaging with Thallium-201 or left ventricular function by echocardiography or radionuclide angiocardiography. With PCT it may become possible to study all three major segments of myocardial performance, i.e., regional blood flow, mechanical function and, most importantly, myocardial metabolism. Each of these segments can either be evaluated separately or in combination. This report briefly describes the principles and technological advantages of the imaging device, reviews currently available radioactive tracers and how they can be employed for the assessment of flow, function and metabolism; and, lastly, discusses possible applications of PCT for the study of cardiac physiology or its potential role in the diagnosis of cardiac disease.

  2. Bayesian image reconstruction: Application to emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Nunez, J.; Llacer, J.

    1989-02-01

    In this paper we propose a Maximum a Posteriori (MAP) method of image reconstruction in the Bayesian framework for the Poisson noise case. We use entropy to define the prior probability and likelihood to define the conditional probability. The method uses sharpness parameters which can be theoretically computed or adjusted, allowing us to obtain MAP reconstructions without the problem of the grey'' reconstructions associated with the pre Bayesian reconstructions. We have developed several ways to solve the reconstruction problem and propose a new iterative algorithm which is stable, maintains positivity and converges to feasible images faster than the Maximum Likelihood Estimate method. We have successfully applied the new method to the case of Emission Tomography, both with simulated and real data. 41 refs., 4 figs., 1 tab.

  3. Positron emission tomography and radiation oncology

    Science.gov (United States)

    Fullerton, PhD, Gary D.; Fox, MD, Peter; Phillips, MD, William T.

    2001-10-01

    Medical physics research is providing new avenues for addressing the fundamental problem of radiation therapy-how to provide a tumor-killing dose while reducing the dose to a non-lethal level for critical organs in adjacent portions of the patient anatomy. This talk reviews the revolutionary impact of Positron Emission Tomography on the practice of radiation oncology. The concepts of PET imaging and the development of "tumor" imaging methods using 18F-DG flouro-deoxyglucose are presented to provide the foundation for contemporary research and application to therapy. PET imaging influences radiation therapy decisions in multiple ways. Imaging of occult but viable tumor metastases eliminates misguided therapy attempts. The ability to distinguish viable tumor from scar tissue and necroses allows reduction of treatment portals and more selective treatments. Much research remains before the clinical benefits of these advances are fully realized.

  4. Reconstruction Algorithms for Positron Emission Tomography and Single Photon Emission Computed Tomography and their Numerical Implementation

    CERN Document Server

    Fokas, A S; Marinakis, V

    2004-01-01

    The modern imaging techniques of Positron Emission Tomography and of Single Photon Emission Computed Tomography are not only two of the most important tools for studying the functional characteristics of the brain, but they now also play a vital role in several areas of clinical medicine, including neurology, oncology and cardiology. The basic mathematical problems associated with these techniques are the construction of the inverse of the Radon transform and of the inverse of the so called attenuated Radon transform respectively. We first show that, by employing mathematical techniques developed in the theory of nonlinear integrable equations, it is possible to obtain analytic formulas for these two inverse transforms. We then present algorithms for the numerical implementation of these analytic formulas, based on approximating the given data in terms of cubic splines. Several numerical tests are presented which suggest that our algorithms are capable of producing accurate reconstruction for realistic phanto...

  5. Amyloid positron emission tomography and cognitive reserve

    Institute of Scientific and Technical Information of China (English)

    Matteo Bauckneht; Agnese Picco; Flavio Nobili; Silvia Morbelli

    2015-01-01

    Alzheimer’s disease(AD) is characterized by a nonlinear progressive course and several aspects influence the relationship between cerebral amount of AD pathology and the clinical expression of the disease. Brain cognitive reserve(CR) refers to the hypothesized capacity of an adult brain to cope with brain damage in order to minimize symptomatology. CR phenomenon contributed to explain the disjunction between the degree of neurodegeneration and the clinical phenotype of AD. The possibility to track brain amyloidosis(Aβ) in vivo has huge relevance for AD diagnosis and new therapeutic approaches. The clinical repercussions of positron emission tomography(PET)-assessed Aβ load are certainly mediated by CR thus potentially hampering the prognostic meaning of amyloid PET in selected groups of patients. Similarly, amyloid PET and cerebrospinal fluid amyloidosis biomarkers have recently provided new evidence for CR. The present review discusses the concept of CR in the framework of available neuroimaging studies and specifically deals with the reciprocal influences between amyloid PET and CR in AD patients and with the potential consequent interventional strategies for AD.

  6. Microfluidics for Positron Emission Tomography Probe Development

    Directory of Open Access Journals (Sweden)

    Ming-Wei Wang

    2010-07-01

    Full Text Available Owing to increased needs for positron emission tomography (PET, high demands for a wide variety of radiolabeled compounds will have to be met by exploiting novel radiochemistry and engineering technologies to improve the production and development of PET probes. The application of microfluidic reactors to perform radiosyntheses is currently attracting a great deal of interest because of their potential to deliver many advantages over conventional labeling systems. Microfluidics-based radiochemistry can lead to the use of smaller quantities of precursors, accelerated reaction rates, and easier purification processes with greater yield and higher specific activity of desired probes. Several proof-of-principle examples along with the basics of device architecture and operation and the potential limitations of each design are discussed. Along with the concept of radioisotope distribution from centralized cyclotron facilities to individual imaging centers and laboratories (“decentralized model”, an easy-to-use, stand-alone, flexible, fully automated, radiochemical microfluidic platform can provide simpler and more cost-effective procedures for molecular imaging using PET.

  7. Single photon emission computed tomography/computed tomography of the skull in malignant otitis externa.

    Science.gov (United States)

    Chakraborty, Dhritiman; Bhattacharya, Anish; Kamaleshwaran, Koramadai Karuppusamy; Agrawal, Kanhaiyalal; Gupta, Ashok Kumar; Mittal, Bhagwant Rai

    2012-01-01

    Malignant otitis externa is a severe, rare infective condition of the external auditory canal and skull base. The diagnosis is generally made from a range of clinical, laboratory, and imaging findings. Technetium 99m methylene diphosphonate bone scintigraphy is known to detect osteomyelitis earlier than computed tomography. The authors present a patient with bilateral malignant otitis externa where the extent of skull base involvement was determined on 3-phase bone scintigraphy with single photon emission computed tomography/computed tomography.

  8. Positron emission tomography-computed tomography has a clinical impact for patients with cervical cancer

    DEFF Research Database (Denmark)

    Sandvik, Rikke Mulvad; Jensen, Pernille Tine; Hendel, Helle W

    2011-01-01

    Many studies have found that positron emission tomography-computed tomography (PET-CT) has a high sensitivity and specificity in the identification of metastasis in cervical cancer. Herlev Hospital, Denmark, has been performing PET-CTs in stage I-IV cervical cancer since 1 May 2006. The present...

  9. Positron emission tomography/computed tomography for optimized colon cancer staging and follow up

    DEFF Research Database (Denmark)

    Engelmann, Bodil Elisabeth; Loft, Annika; Kjær, Andreas;

    2014-01-01

    OBJECTIVES: Optimal management of colon cancer (CC) requires detailed assessment of extent of disease. This study prospectively investigates the diagnostic accuracy of 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (PET/CT) for staging and detection of recurrence...

  10. An online emission spectral tomography system with digital signal processor.

    Science.gov (United States)

    Wan, Xiong; Xiong, Wenlin; Zhang, Zhimin; Chang, Fangfei

    2009-03-30

    Emission spectral tomography (EST) has been adopted to test the three-dimensional distribution parameters of fluid fields, such as burning gas, flame and plasma etc. In most cases, emission spectral data received by the video cameras are enormous so that the emission spectral tomography calculation is often time-consuming. Hence, accelerating calculation becomes the chief factor that one must consider for the practical application of EST. To solve the problem, a hardware implementation method was proposed in this paper, which adopted a digital signal processor (DSP) DM642 in an emission spectral tomography test system. The EST algorithm was fulfilled in the DSP, then calculation results were transmitted to the main computer via the user datagram protocol. Compared with purely VC++ software implementations, this new approach can decrease the calculation time significantly.

  11. Positron emission tomography and migraine. Tomographie par emission de positons et migraine

    Energy Technology Data Exchange (ETDEWEB)

    Chabriat, H. (CEA, 91 - Orsay (France). Service Hospitalier Frederic Joliot)

    1992-04-01

    Positron emission tomography (PET) is a brain imaging technique that allows in vivo studies of numerous physiological parameters. There have been few PET studies in migraine patients. Cerebral blood flow changes with no variations in brain oxygen consumption have been reported in patients with prolonged neurologic manifestations during migraine attacks. Parenteral administration of reserpine during migraine headache has been followed by a fall in the overall cerebral uptake of glucose. The small sample sizes and a number of methodologic problems complicate the interpretation of these results. Recent technical advances and the development of new PET tracers can be expected to provide further insight into the pathophysiology of migraine. Today cerebral cortex 5 HT{sub 2} serotonin receptors can be studied in migraine patients with PET.

  12. Single-photon emission computed tomography and positron-emission tomography assays for tissue oxygenation.

    Science.gov (United States)

    Chapman, J D; Schneider, R F; Urbain, J L; Hanks, G E

    2001-01-01

    Radiotherapy prescription can now be customized to target the major mechanism(s) of resistance of individual tumors. In that regard, functional imaging techniques should be exploited to identify the dominant mechanism(s). Tumor biology research has identified several mechanisms of tumor resistance that may be unique to radiation treatments. These fall into 3 broad areas associated with (1) tumor hypoxic fraction, (2) tumor growth rate, (3) and the intrinsic radiosensitivity of tumor clonogens. Imaging research has markers in various stages of development for quantifying relevant information about each of these mechanisms, and those that measure tumor oxygenation and predict for radioresistance are the most advanced. Positron-emission tomography (PET) measurement of oxygen 15 has yielded important information, particularly about brain tissue perfusion, metabolism, and function. Indirect markers of tumor hypoxia have exploited the covalent binding of bioreductive intermediates of azomycin-containing compounds whose uptakes are inversely proportional to intracellular oxygen concentrations. Pilot clinical studies with single-photon emission computed tomography (SPECT) and PET detection of radiolabeled markers to tumor hypoxia have been reported. Recently, other studies have attempted to exploit the reduction properties of both technetium and copper chelates for the selective deposition of radioactive metals in hypoxic tissues. A growing number of potentially useful isotopes are now available for labeling several novel chemicals that could have the appropriate specificity and sensitivity. Preclinical studies with "microSPECT" and "microPET" will be important to define the optimal radiodiagnostic(s) for measuring tissue oxygenation and for determining the time after their administration for optimal hypoxic signal acquisition. Radiolabeled markers of growth kinetics and intrinsic radiosensitivity of cells in solid tumors are also being developed. We conclude that

  13. Single photon emission computed tomography/computed tomography for malignant otitis externa: lesion not shown on planar image.

    Science.gov (United States)

    Chen, Yu-Hung; Hsieh, Hung-Jen

    2013-01-01

    Malignant otitis externa is a severe and rare infection of the external acoustic meatus. Triphasic bone and (67)Ga scintigraphies are used to initial detect and follow-up the response of therapy. With single photon emission computed tomography/computed tomography images, the diagnostic sensitivity is higher. We presented a case with malignant otitis externa with initial negative planar scintigraphic finding. The lesion was detected by photon emission computed tomography/computed tomography images. We concluded that the photon emission computed tomography/computed tomography should be performed routinely for patients with suspected malignant otitis externa, even without evidence of lesion on planar images.

  14. Positron emission tomography-computed tomography has a clinical impact for patients with cervical cancer

    DEFF Research Database (Denmark)

    Sandvik, Rikke Mulvad; Jensen, Pernille Tine; Hendel, Helle Westergren;

    2011-01-01

    Many studies have found that positron emission tomography-computed tomography (PET-CT) has a high sensitivity and specificity in the identification of metastasis in cervical cancer. Herlev Hospital, Denmark, has been performing PET-CTs in stage I-IV cervical cancer since 1 May 2006. The present...... study investigates the positive (PPV) and negative predictive value (NPV) of PET-CT in stage I disease and the clinical impact of the scan results in all disease stages....

  15. Positron emission tomography-computed tomography has a clinical impact for patients with cervical cancer

    DEFF Research Database (Denmark)

    Sandvik, Rikke Mulvad; Jensen, Pernille Tine; Hendel, Helle W;

    2011-01-01

    Many studies have found that positron emission tomography-computed tomography (PET-CT) has a high sensitivity and specificity in the identification of metastasis in cervical cancer. Herlev Hospital, Denmark, has been performing PET-CTs in stage I-IV cervical cancer since 1 May 2006. The present s...... study investigates the positive (PPV) and negative predictive value (NPV) of PET-CT in stage I disease and the clinical impact of the scan results in all disease stages....

  16. Combined single photon emission computerized tomography and conventional computerized tomography: Clinical value for the shoulder surgeons?

    Directory of Open Access Journals (Sweden)

    Michael T Hirschmann

    2011-01-01

    Full Text Available With the cases described, we strive to introduce single photon emission computerized tomography in combination with conventional computer tomography (SPECT/CT to shoulder surgeons, illustrate the possible clinical value it may offer as new diagnostic radiologic modality, and discuss its limitations. SPECT/CT may facilitate the establishment of diagnosis, process of decision making, and further treatment for complex shoulder pathologies. Some of these advantages were highlighted in cases that are frequently seen in most shoulder clinics.

  17. 64Cu loaded liposomes as positron emission tomography imaging agents

    DEFF Research Database (Denmark)

    Petersen, Anncatrine Luisa; Binderup, Tina; Rasmussen, Palle;

    2011-01-01

    We have developed a highly efficient method for utilizing liposomes as imaging agents for positron emission tomography (PET) giving high resolution images and allowing direct quantification of tissue distribution and blood clearance. Our approach is based on remote loading of a copper-radionuclid...

  18. Quantification in dynamic and small-animal positron emission tomography

    NARCIS (Netherlands)

    Disselhorst, Johannes Antonius

    2011-01-01

    This thesis covers two aspects of positron emission tomography (PET) quantification. The first section addresses the characterization and optimization of a small-animal PET/CT scanner. The sensitivity and resolution as well as various parameters affecting image quality (reconstruction settings, type

  19. Recent Developments in Positron Emission Tomography (PET) Instrumentation

    Science.gov (United States)

    Derenzo, S. E.; Budinger, T. F.

    1986-04-01

    This paper presents recent detector developments and perspectives for positron emission tomography (PET) instrumentation used for medical research, as well as the physical processes in positron annihilation, photon scattering and detection, tomograph design considerations, and the potentials for new advances in detectors.

  20. Positron Emission Tomography : background, possibilities and perspectives in neuroscience

    NARCIS (Netherlands)

    Paans, AMJ

    1997-01-01

    Positron Emission Tomography (PET) is a method for determining biochemical and physiological processes in vivo in a quantitative way. This includes the measurement of the pharmacokinetics of labeled drugs and the measurement of the effects of drugs and/or therapy on metabolism. Also deviations of no

  1. Fluorinated amino acids for tumour imaging with positron emission tomography.

    NARCIS (Netherlands)

    Laverman, P.; Boerman, O.C.; Corstens, F.H.M.; Oyen, W.J.G.

    2002-01-01

    The currently preferred radiopharmaceutical for positron emission tomography (PET) in oncology is 2-[(18)F]fluoro-deoxyglucose (FDG). Increased accumulation of this deoxyglucose analogue in tumour cells is based on elevated glucose metabolism by tumour cells and subsequent trapping in the cells. In

  2. Analytic evaluation of statistical projection operators for emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kuruc, A.

    1996-05-01

    The purpose of this report is to outline an approach to the numerical construction of statistically efficient estimators for linear functionals in emission tomography (ET) that is more efficient than the approach used in [Kur97]. For the sake of brevity, we will assume familiarity with the notation and material in [Kur97].

  3. Positron emission tomography in drug development and drug evaluation

    NARCIS (Netherlands)

    Paans, AMJ; Vaalburg, W

    2000-01-01

    Positron Emission Tomography (PET) is an imaging modality which can determine biochemical and physiological processes in vivo in a quantitative way by using radiopharmaceuticals labeled with positron emitting radionuclides as C-11, N-13, O-15 and F-18 and by measuring the annihilation radiation usin

  4. Multifocal sparganosis mimicking lymphoma involvement: Multimodal imaging findings of ultrasonography, CT, MRI, and position emission tomography-computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Heo, So Young; Park, Ji Yeon; Park, Noh Hyuck; Park, Chan Sub; Kim, Tae Jung [Myongji Hospital, Seonam University College of Medicine, Goyang (Korea, Republic of); Yi, Seong Yoon [Dev. of Hematology-Omcology, Dept. of Internal Medicine, Inje University Ilsan Paik Hospital, Goyang (Korea, Republic of); Jun, Hyun Jung [Dev. of Hematology-Omcology, Dept. of Internal Medicine, Seoul Medical Center, Seoul (Korea, Republic of)

    2016-01-15

    Sparganosis is a rare parasitic disease caused by the migrating plerocercoid larva of Spirometra species tapeworms. The most frequent clinical manifestation is a subcutaneous nodule resembling a neoplasm. In this study, we presented multimodal findings of ultrasonography, computed tomography, magnetic resonance imaging, positron emission tomography-computed tomography and follow-up imagings on multifocal sparganosis, mimicking lymphoma involvement in a patient with lymphoma.

  5. Monte Carlo Simulation Of Emission Tomography And Other Medical Imaging Techniques

    Science.gov (United States)

    Harrison, Robert L.

    2010-01-01

    An introduction to Monte Carlo simulation of emission tomography. This paper reviews the history and principles of Monte Carlo simulation, then applies these principles to emission tomography using the public domain simulation package SimSET (a Simulation System for Emission Tomography) as an example. Finally, the paper discusses how the methods are modified for X-ray computed tomography and radiotherapy simulations. PMID:20733931

  6. Use of high-resolution computed tomography and positron emission tomography/computed tomography in the management of stage IA adenocarcinoma.

    Science.gov (United States)

    Miyata, Yoshihiro; Tsutani, Yasuhiro; Okada, Morihito

    2012-01-01

    Preoperative determination of malignant behavior is critical in choosing suitable therapeutic strategies such as sublobar resection for patients with small lung cancers. The aim of present review was to evaluate high-resolution computed tomography and fluorodeoxyglucose-positron emission tomography/computed tomography as tools for management of clinical stage IA adenocarcinoma.

  7. ENVISION, developing Positron Emission Tomography for particle therapy

    CERN Multimedia

    2013-01-01

    Particle therapy is an advanced technique of cancer radiation therapy, using protons or other ions to target the cancerous mass. ENVISION aims at developing medical imaging tools to improve the dose delivery to the patient, to ensure a safer and more effective treatment. The animation illustrates the use of Positron Emission Tomography (PET) for monitoring the dose during treatment. Produced by: CERN KT/Life Sciences and ENVISION Project Management: Manuela Cirilli 3D animation: Jeroen Huijben, Nymus3d

  8. Current and future technological trends in positron emission tomography.

    Science.gov (United States)

    Karp, J S; Freifelder, R

    1992-04-01

    Current trends in positron emission tomography (PET) instrumentation are examined, with an emphasis on providing information suitable to the prospective PET user. Basic principles underlying PET are explained and information on performance measurements, techniques, and quantitation are given in order to allow the user to compare and contrast different types of PET scanners. These scanner designs are described. Specific examples are given and the combination of PET with other modalities is discussed.

  9. Emission and transmission noise propagation in positron emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Gullberg, G.T.; Huesman, R.H.

    1979-06-01

    Errors in positron emission computed tomograms are the result of noise propagated from three sources: (1) the statistical fluctuation in the positron coincidence events; (2) the statistical fluctuation in the incident transmission beam; and (3) the statistical fluctuation in the transmitted beam. The data for the transmission study in (2) and (3) are used to compensate for internal absorption of the distributed positron source. For the reconstruction of a circular phantom using the convolution algorithm, the percent root-mean-square uncertainty (%RMS) is related to the total measured positron events C and the incident photon flux per cm I/sub 0/. Our derivation of the %RMS uncertainty based on the propagation of errors yields a simple expression: %RMS = ..sqrt..K/sub 1//C + K/sub 2//I/sub 0/. The constants K/sub 1/ = 4.52 x 10/sup 8/ and K/sub 2/ = 1.48 x 10/sup 8/ were determined for a 20 cm diameter disc based on computer simulation. The projection data were analytically calculated with an attenuation coefficient ..mu.. = 0.0958 cm/sup -1/ for 140 angles between 0 and ..pi... Poisson noise was added to the positron coincidence events, the incident transmission events I/sub 0/, and the transmitted events. These results indicate that for a total number of incident transmission photons per cm of 2.0 x 10/sup 5/, the contrast resolution for a fixed spatial resolution is limited to 27% even with an infinite number of emission events. For a total of 10/sup 6/ emission events the contrast resolution is 34%.

  10. Positron emission tomography of incidentally detected small pulmonary nodules

    DEFF Research Database (Denmark)

    Fischer, B M; Mortensen, J; Dirksen, A;

    2004-01-01

    The aim of this study was to assess the value of fluorodeoxyglucose positron emission tomography (FDG PET) imaging of small pulmonary nodules incidentally detected by spiral computed tomography (CT) in a high-risk population. Ten patients (five females, five males, aged 54-72 years) were recruited...... (approx. 3.3% of the entire study population). The prevalence of malignancy in this group was 50%. The accuracy of PET was high, in spite of the fact that seven patients had nodules smaller than 15 mm and two patients had bronchoalveolar cell carcinoma. This small prospective study indicates...... that subsequent assessment with FDG PET of small pulmonary nodules incidentally detected by CT has the potential to minimize the numbers of invasive procedures performed in individuals with a benign pulmonary lesion. FDG PET also increases the possibility of an early diagnosis as compared to the strategy...

  11. Acute Calculous Cholecystitis Missed on Computed Tomography and Ultrasound but Diagnosed with Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

    Directory of Open Access Journals (Sweden)

    Carina Mari Aparici

    2016-01-01

    Full Text Available We present a case of a 69-year-old patient who underwent ascending aortic aneurysm repair with aortic valve replacement. On postsurgical day 12, he developed leukocytosis and low-grade fevers. The chest computed tomography (CT showed a periaortic hematoma which represents a postsurgical change from aortic aneurysm repair, and a small pericardial effusion. The abdominal ultrasound showed cholelithiasis without any sign of cholecystitis. Finally, a fluorodeoxyglucose (FDG-positron emission tomography (PET/CT examination was ordered to find the cause of fever of unknown origin, and it showed increased FDG uptake in the gallbladder wall, with no uptake in the lumen. FDG-PET/CT can diagnose acute cholecystitis in patients with nonspecific clinical symptoms and laboratory results.

  12. Positron Emission Tomography (PET) and breast cancer in clinical practice

    Energy Technology Data Exchange (ETDEWEB)

    Lavayssiere, Robert [Centre d' Imagerie Paris-Nord, 1, avenue Charles Peguy, 95200 Sarcelles (France); Institut du Sein Henri Hartmann (ISHH), 1, rue des Dames Augustines, 92200 Neuilly sur Seine (France)], E-mail: cab.lav@wanadoo.fr; Cabee, Anne-Elizabeth [Centre d' Imagerie Paris-Nord, 1, avenue Charles Peguy, 95200 Sarcelles (France); Institut du Sein Henri Hartmann (ISHH), 1, rue des Dames Augustines, 92200 Neuilly sur Seine (France); Centre RMX, 80, avenue Felix Faure, 75105 Paris (France); Filmont, Jean-Emmanuel [Institut du Sein Henri Hartmann (ISHH), 1, rue des Dames Augustines, 92200 Neuilly sur Seine (France); American Hospital of Paris, Nuclear Medicine, 63, boulevard Victor Hugo - BP 109, 92202 Neuilly sur Seine Cedex (France)

    2009-01-15

    The landscape of oncologic practice has changed deeply during the past few years and there is now a need, through a multidisciplinary approach, for imaging to provide accurate evaluation of morphology and function and to guide treatment (Image Guided Therapy). Increasing emphasis has been put on Position Emission Tomography (PET) role in various cancers among clinicians and patients despite a general context of healthcare expenditure limitation. Positron Emission Tomography has currently a limited role in breast cancer, but also general radiologists and specialists should be aware of these indications, especially when staging aggressive cancers and looking for recurrence. Currently, the hybrid systems associating PET and Computed Tomography (CT) and in the same device [Rohren EM, Turkington TG, Coleman RE. Clinical applications of PET in oncology. Radiology 2004;231:305-32; Blodgett TM, Meltzer CM, Townsend DW. PET/CT: form and function. Radiology 2007;242:360-85; von Schulthess GK, Steinert HC, Hany TF. Integrated PET/CT: current applications and futures directions. Radiology 2006;238(2):405-22], or PET-CT, are more commonly used and the two techniques are adding their potentialities. Other techniques, MRI in particular, may also compete with PET in some instance and as far as ionizing radiations dose limitation is considered, some breast cancers becoming some form of a chronic disease. Breast cancer is a very complex, non-uniform, disease and molecular imaging at large may contribute to a better knowledge and to new drugs development. Ongoing research, Positron Emission Mammography (PEM) and new tracers, are likely to bring improvements in patient care [Kelloff GJ, Hoffman JM, Johnson B, et al. Progress and promise of FDG-PET Imaging for cancer patient management and oncologic drug development. Clin Cancer Res 2005;1(April (8)): 2005].

  13. Fasciola Hepatica Mimicking Malignancy on 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

    Science.gov (United States)

    Sürücü, Erdem; Demir, Yusuf; Dülger, Ahmet C.; Batur, Abdüssamed; Ölmez, Şehmus; Kitapçı, Mehmet T.

    2016-01-01

    A 48-year-old female with complaints of gastrointestinal symptoms such as abdominal pain, fatigue, vomiting, nausea, and weight loss was diagnosed with neuroendocrine tumor after removal of a 2 mm lesion from the stomach with endoscopic biopsy. Her magnetic resonance imaging that was performed due to on-going symptoms showed multiple linear hypointense lesions in the liver. Positron emission tomography/computed tomography (PET/CT) scan was performed for differential diagnosis, which showed high fluorodeoxyglucose (FDG) uptake in these lesions. Clinical and laboratory findings revealed the final diagnosis as Fasciola hepatica. The imaging features of this case is presented to aid in differentiating this infectious disease from malignancy and avoid misdiagnosis on FDG-PET/CT. PMID:27751978

  14. Fasciola Hepatica Mimicking Malignancy on 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

    Directory of Open Access Journals (Sweden)

    Erdem Sürücü

    2016-10-01

    Full Text Available A 48-year-old female with complaints of gastrointestinal symptoms such as abdominal pain, fatigue, vomiting, nausea, and weight loss was diagnosed with neuroendocrine tumor after removal of a 2 mm lesion from the stomach with endoscopic biopsy. Her magnetic resonance imaging that was performed due to on-going symptoms showed multiple linear hypointense lesions in the liver. Positron emission tomography/computed tomography (PET/CT scan was performed for differential diagnosis, which showed high fluorodeoxyglucose (FDG uptake in these lesions. Clinical and laboratory findings revealed the final diagnosis as Fasciola hepatica. The imaging features of this case is presented to aid in differentiating this infectious disease from malignancy and avoid misdiagnosis on FDG-PET/CT.

  15. Oncological applications of positron emission tomography with fluorine-18 fluorodeoxyglucose

    Energy Technology Data Exchange (ETDEWEB)

    Rigo, P. [Division of Nuclear Medicine, University Hospital, Sart Tilman, Liege (Belgium); Paulus, P. [Division of Nuclear Medicine, University Hospital, Sart Tilman, Liege (Belgium); Kaschten, B.J. [Cyclotron Research Centre, University of Liege and Division of Neurosurgery, University Hospital, Sart Tilman, Liege (Belgium); Hustinx, R. [Division of Nuclear Medicine, University Hospital, Sart Tilman, Liege (Belgium); Bury, T. [Division of Pneumology, University Hospital, Sart Tilman, Liege (Belgium); Jerusalem, G. [Division of Onco-Hematology, University Hospital, Sart Tilman, Liege (Belgium); Benoit, T. [Division of Nuclear Medicine, University Hospital, Sart Tilman, Liege (Belgium); Foidart-Willems, J. [Division of Nuclear Medicine, University Hospital, Sart Tilman, Liege (Belgium)

    1996-12-01

    Positron emission tomography (PET) is now primarily used in oncological indication owing to the successful application of fluorine-18 fluorodeoxyglucose (FDG) in an increasing number of clinical indications at different stages of diagnosis, and for staging and follow-up. This review first considers the biological characteristics of FDG and then discusses methodological considerations regarding its use. Clinical indications are considered, and the results achieved in respect of various organs and tumour types are reviewed in depth. The review concludes with a brief consideration of the ways in which clinical PET might be improved. (orig.). With 6 figs., 8 tabs.

  16. Serotonin synthesis studied with positron emission tomography, (PET)

    DEFF Research Database (Denmark)

    Honoré, Per Gustaf Hartvig; Lundquist, Pinelopi

    Positron emission tomography (PET) has the potential to study the biosynthesis and release of serotonin (5HT) at brain serotonergic neurons. PET requires probe compounds with specific attributes to enable imaging and quantification of biological processes. This section focuses on probes to measure......-L-(beta-11C tryptophan) (5HTP) quantifies the activity of amino acid decarboxylase in the conversion to 5HT. On the other hand, alpha-methyl-tryptophan (AMT) measures the conversion to the corresponding 5-hydroxytryptophan analogue. The irreversible binding of the PET probe 5HTP in the monkey brain was lower...

  17. The statistical efficiency of filtered backprojection in emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kuruc, A.

    1995-09-25

    While there has been much interest in developing tomographic reconstruction algorithms that are more statistically efficient than filtered backprojection (FB), the degree of improvement possible has not been well understood. We present an algorithm-independent theory of statistical accuracy attainable in emission tomography that provides a geometrical interpretation of the statistical efficiency of FB. Our analysis shows that, in general, one can build unbiased estimators with smaller variance than FB. The improvement in performance is obtained by exploiting the range properties of the Radon transform.

  18. RPC: from High Energy Physics to Positron Emission Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Belli, G; Vecchi, C De; Giroletti, E; Musitelli, G; Nardo, R; Necchi, M M; Pagano, D; Ratti, S P; Riccardi, C; Sani, G; Torre, P; Vitulo, P; Viviani, C [Dipartimento di Fisica Nucleare e Teorica - Universita di Pavia and Istituto Nazionale di Fisica Nucleare - Sezione di Pavia - via A. Bassi, 6 Pavia - (Italy)

    2006-05-15

    A low cost gas-based charged particle detector, the Resistive Plate Counter (RPC) intensively used in fixed target and collider high energy experiments, is proposed as basic detector for Positron Emission Tomography. The performance of RPCs in terms of intrinsic space and time resolution and electronic pulse height response, makes it possible to transform standard RPCs into photon detectors and therefore to compensate for the photon sensitivity of scintillating crystals, when the efficiency of the complex crystal + photomultiplier is turned into standard quantum efficiency (q.e). Prototype multigap glass RPCs were developed which optimize {gamma} detection efficiency and thus might substitute the traditional scintillators setups.

  19. [Positron emission tomography: diagnostic imaging on a molecular level].

    Science.gov (United States)

    Allemann, K; Wyss, M; Wergin, M; Bley, C Rohrer; Ametamay, S; Bruehlmeier, M; Kaser-Hotz, B

    2004-08-01

    In human medicine positron emission tomography (PET) is a modern diagnostic imaging method. In the present paper we outline the physical principles of PET and give an overview over the main clinic fields where PET is being used, such as neurology, cardiology and oncology. Moreover, we present a current project in veterinary medicine (in collaboration with the Paul Scherrer Institute and the University Hospital Zurich), where a hypoxia tracer is applied to dogs and cats suffering from spontaneous tumors. Finally new developments in the field of PET were discussed.

  20. Kinetic modeling in pre-clinical positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kuntner, Claudia [AIT Austrian Institute of Technology GmbH, Seibersdorf (Austria). Biomedical Systems, Health and Environment Dept.

    2014-07-01

    Pre-clinical positron emission tomography (PET) has evolved in the last few years from pure visualization of radiotracer uptake and distribution towards quantification of the physiological parameters. For reliable and reproducible quantification the kinetic modeling methods used to obtain relevant parameters of radiotracer tissue interaction are important. Here we present different kinetic modeling techniques with a focus on compartmental models including plasma input models and reference tissue input models. The experimental challenges of deriving the plasma input function in rodents and the effect of anesthesia are discussed. Finally, in vivo application of kinetic modeling in various areas of pre-clinical research is presented and compared to human data.

  1. F-18 Fluorodeoxy Glucose Positron Emission Tomography/Computed Tomography Findings in a Rare Case of Penile Leiomyosarcoma

    Directory of Open Access Journals (Sweden)

    Kuruva Manohar

    2011-01-01

    Full Text Available Penile cancer is a rare entity accounting for only 0.4% all male malignancies. Penile leiomyosarcomas are even rarer with only around 35 cases reported in literature. We report a rare case of penile leiomyosarcoma illustrating F-18 Fluorodeoxy glucose (FDG positron emission tomography/computed tomography (PET/CT features and histopathology correlation.

  2. Anti-3-[18F]FACBC Positron Emission Tomography-Computerized Tomography and 111In-Capromab Pendetide Single Photon Emission Computerized Tomography-Computerized Tomography for Recurrent Prostate Carcinoma: Results of a Prospective Clinical Trial

    Science.gov (United States)

    Schuster, David M.; Nieh, Peter T.; Jani, Ashesh B.; Amzat, Rianot; Bowman, F. DuBois; Halkar, Raghuveer K.; Master, Viraj A.; Nye, Jonathon A.; Odewole, Oluwaseun A.; Osunkoya, Adeboye O.; Savir-Baruch, Bital; Alaei-Taleghani, Pooneh; Goodman, Mark M.

    2014-01-01

    Purpose We prospectively evaluated the amino acid analogue positron emission tomography radiotracer anti-3-[18F]FACBC compared to ProstaScint® (111In-capromab pendetide) single photon emission computerized tomography-computerized tomography to detect recurrent prostate carcinoma. Materials and Methods A total of 93 patients met study inclusion criteria who underwent anti-3-[18F]FACBC positron emission tomography-computerized tomography plus 111In-capromab pendetide single photon emission computerized tomography-computerized tomography for suspected recurrent prostate carcinoma within 90 days. Reference standards were applied by a multidisciplinary board. We calculated diagnostic performance for detecting disease. Results In the 91 of 93 patients with sufficient data for a consensus on the presence or absence of prostate/bed disease anti-3-[18F]FACBC had 90.2% sensitivity, 40.0% specificity, 73.6% accuracy, 75.3% positive predictive value and 66.7% negative predictive value compared to 111In-capromab pendetide with 67.2%, 56.7%, 63.7%, 75.9% and 45.9%, respectively. In the 70 of 93 patients with a consensus on the presence or absence of extraprostatic disease anti-3-[18F]FACBC had 55.0% sensitivity, 96.7% specificity, 72.9% accuracy, 95.7% positive predictive value and 61.7% negative predictive value compared to 111In-capromabpendetide with10.0%, 86.7%, 42.9%, 50.0% and 41.9%, respectively. Of 77 index lesions used to prove positivity histological proof was obtained in 74 (96.1%). Anti-3-[18F]FACBC identified 14 more positive prostate bed recurrences (55 vs 41) and 18 more patients with extraprostatic involvement (22 vs 4). Anti-3-[18F]FACBC positron emission tomography-computerized tomography correctly up-staged 18 of 70 cases (25.7%) in which there was a consensus on the presence or absence of extraprostatic involvement. Conclusions Better diagnostic performance was noted for anti-3-[18F]FACBC positron emission tomography-computerized tomography than for 111In

  3. Benign breast lesions detected by positron emission tomography-computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Benveniste, Ana P., E-mail: apbenveniste@mdanderson.org [Department of Diagnostic Radiology,The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Yang, Wei, E-mail: wyang@mdanderson.org [Department of Diagnostic Radiology,The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Benveniste, Marcelo F., E-mail: mfbenveniste@mdanderson.org [Department of Diagnostic Radiology,The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Mawlawi, Osama R., E-mail: omawlawi@mdanderson.org [Department of imaging physics, The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Marom, Edith M., E-mail: emarom@mdanderson.org [Department of Diagnostic Radiology,The University of Texas MD Anderson Cancer Center, Houston, TX (United States)

    2014-06-15

    {sup 18}F-fluorodeoxyglucose positron emission computed tomography (FDG PET-CT) is widely used in the initial staging and response evaluation of patients with malignancy. This review describes a spectrum of benign breast findings incidentally detected by FDG PET-CT at staging that may be misinterpreted as malignancy. We describe the pattern of distribution and intensity of FDG uptake in a spectrum of benign breast diseases with their corresponding typical morphological imaging characteristics to help the nuclear medicine physician and/or general radiologist identify benign lesions, avoiding unnecessary breast imaging work-up and biopsies.

  4. Instrumentation for time of-flight position emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Ullah, Muhammad Nasir; Pratiwi, Eva; Yeom, Jung Yeol [Korea University, Seoul (Korea, Republic of); Cheon, Ji Min; Choi, Ho Jung [Kumoh National Institute of Technology, Gumi (Korea, Republic of)

    2016-06-15

    Positron emission tomography (PET) is a molecular imaging modality that provides information at the molecular level. This system is composed of radiation detectors to detect incoming coincident annihilation gamma photons emitted from the radiopharmaceutical injected into a patient's body and uses these data to reconstruct images. A major trend in PET instrumentation is the development of time-of-flight positron emission tomography (ToF-PET). In ToF-PET, the time information (the instant the radiation is detected) is incorporated for image reconstruction. Therefore, precise and accurate timing recording is crucial in ToF-PET. ToF-PET leads to better localization of the annihilation event and thus results in overall improvement in the signal-to-noise ratio (SNR) of the reconstructed image. Several factors affect the timing performance of ToF-PET. In this article, the background, early research and recent advances in ToF-PET instrumentation are presented. Emphasis is placed on the various types of scintillators, photodetectors and electronic circuitry for use in ToF-PET, and their impact on timing resolution is discussed.

  5. Single-photon emission computed tomography/computed tomography in brain tumors.

    Science.gov (United States)

    Schillaci, Orazio; Filippi, Luca; Manni, Carlo; Santoni, Riccardo

    2007-01-01

    Anatomic imaging procedures (computed tomography [CT] and magnetic resonance imaging [MRI]) have become essential tools for brain tumor assessment. Functional images (positron emission tomography [PET] and single-photon emission computed tomography [SPECT]) can provide additional information useful during the diagnostic workup to determine the degree of malignancy and as a substitute or guide for biopsy. After surgery and/or radiotherapy, nuclear medicine examinations are essential to assess persistence of tumor, to differentiate recurrence from radiation necrosis and gliosis, and to monitor the disease. The combination of functional images with anatomic ones is of the utmost importance for a full evaluation of these patients, which can be obtained by means of imaging fusion. Despite the fast-growing diffusion of PET, in most cases of brain tumors, SPECT studies are adequate and provide results that parallel those obtained with PET. The main limitation of SPECT imaging with brain tumor-seeking radiopharmaceuticals is the lack of precise anatomic details; this drawback is overcome by the fusion with morphological studies that provide an anatomic map to scintigraphic data. In the past, software-based fusion of independently performed SPECT and CT or MRI demonstrated usefulness for brain tumor assessment, but this process is often time consuming and not practical for everyday nuclear medicine studies. The recent development of dual-modality integrated imaging systems, which allow the acquisition of SPECT and CT images in the same scanning session, and their co-registration by means of the hardware, has facilitated this process. In SPECT studies of brain tumors with various radiopharmaceuticals, fused images are helpful in providing the precise localization of neoplastic lesions, and in excluding the disease in sites of physiologic tracer uptake. This information is useful for optimizing diagnosis, therapy monitoring, and radiotherapy treatment planning, with a

  6. CO2BOLD assessment of moyamoya syndrome: Validation with single photon emission computed tomography and positron emission tomography imaging

    Science.gov (United States)

    Pellaton, Alain; Bijlenga, Philippe; Bouchez, Laurie; Cuvinciuc, Victor; Barnaure, Isabelle; Garibotto, Valentina; Lövblad, Karl-Olof; Haller, Sven

    2016-01-01

    AIM To compare the assessment of cerebrovascular reserve (CVR) using CO2BOLD magnetic resonance imaging (MRI) vs positron emission tomography (PET) and single photon emission computed tomography (SPECT) as reference standard. METHODS Ten consecutive patients (8 women, mean age of 41 ± 26 years) with moyamoya syndrome underwent 14 pre-surgical evaluations for external-internal carotid artery bypass surgery. CVR was assessed using CO2BOLD and PET (4)/SPECT (11) with a maximum interval of 36 d, and evaluated by two experienced neuroradiologists. RESULTS The inter-rater agreement was 0.81 for SPECT (excellent), 0.43 for PET (fair) and 0.7 for CO2BOLD (good). In 9/14 cases, there was a correspondence between CO2BOLD and PET/SPECT. In 4/14 cases, CVR was over-estimated in CO2BOLD, while in 1/14 case, CVR was underestimated in CO2BOLD. The sensitivity of CO2BOLD was 86% and a specificity of 43%. CONCLUSION CO2BOLD can be used for pre-surgical assessment of CVR in patients with moyamoya syndrome and combines the advantages of absent irradiation, high availability of MRI and assessment of brain parenchyma, cerebral vessels and surrogate CVR in one stop. PMID:27928470

  7. Plasma Emission Profile Recreation using Soft X-Ray Tomography

    Science.gov (United States)

    Page, J. W.; Mauel, M. E.; Levesque, J. P.

    2015-11-01

    With sufficient views from multiple diode arrays, soft X-ray tomography is an invaluable plasma diagnostic because it is a non-perturbing method to reconstruct the emission within the interior of the plasma. In preparation for the installation of new SXR arrays in HBT-EP, we compute high-resolution tomographic reconstructions of discharges having kink-like structures that rotate nearly rigidly. By assuming a uniform angular mapping from the kink mode rotation, Δϕ ~ ωΔ t, a temporal sequence from a single 16-diode fan array represents as many as 16 x 100 independent views. We follow the procedure described by Wang and Granetz and use Bessel basis functions to take the inverse Radon transform. This transform is fit to our data using a least-squares method to estimate the internal SXR emissivity as a sum of polar functions. By varying different parameters of the transformation, we optimize the quality of our recreation of the emission profile and quantify how the reconstruction changes with the azimuthal order of the transform. Supported by U.S. DOE Grant DE-FG02-86ER53222.

  8. Positron Emission Tomography with Three-Dimensional Reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Erlandsson, K.

    1996-10-01

    The development of two different low-cost scanners for positron emission tomography (PET) based on 3D acquisition are presented. The first scanner consists of two rotating scintillation cameras, and produces quantitative images, which have shown to be clinically useful. The second one is a system with two opposed sets of detectors, based on the limited angle tomography principle, dedicated for mammographic studies. The development of low-cost PET scanners can increase the clinical impact of PET, which is an expensive modality, only available at a few centres world-wide and mainly used as a research tool. A 3D reconstruction method was developed that utilizes all the available data. The size of the data-sets is considerably reduced, using the single-slice rebinning approximation. The 3D reconstruction is divided into 1D axial deconvolution and 2D transaxial reconstruction, which makes it relatively fast. This method was developed for the rotating scanner, but was also implemented for multi-ring scanners with and without inter plane septa. An iterative 3D reconstruction method was developed for the limited angle scanner, based on the new concept of `mobile pixels`, which reduces the finite pixel errors and leads to an improved signal to noise ratio. 100 refs.

  9. Studies of the brain cannabinoid system using positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Gatley, S.J.; Volkow, N.D.

    1995-10-01

    Studies using radiolabeled psychoactive drugs in conjunction with positron emission tomography (PET) have permitted the imaging of binding sites in the human brain. Similar studies of marijuana have been hampered by the unsuitability of radiolabeled THC for PET studies, and the current unavailability of other in vivo imaging agents for cannabinoid receptors. Recent developments in medicinal chemistry suggest that a PET radiotracer for cannabinoid receptors will soon become available. This chapter briefly reviews these developments, together with the results of PET studies of the effects of marijuana and other abused drugs on brain metabolism. It also reviews PET studies of cocaine binding sites, to demonstrate the kind of investigations that will be possible when a cannabinoid receptor PET radioligand becomes available.

  10. A Case of Corticobasal Degeneration Studied with Positron Emission Tomography

    Directory of Open Access Journals (Sweden)

    H. Nagasawa

    1993-01-01

    Full Text Available We measured cerebral blood flow, oxygen metabolism, glucose utilization, and dopamine metabolism in the brain of a patient with corticobasal degeneration using positron emission tomography (PET. The clinical picture is distinctive, comprising features referable to both cortical and basal ganglionic dysfunction. Brain imagings of glucose and dopamine metabolism can demonstrate greater abnormalities in the cerebral cortex and in the striatum contralateral to the more affected side than those of blood flow and oxygen metabolism. This unique combination study measuring both cerebral glucose utilization and dopamine metabolism in the nigrostriatal system can provide efficient information about the dysfunctions which are correlated with individual clinical symptoms, and this study is essential to diagnosis of corticobasal degeneration.

  11. Positron emission tomography in CNS drug discovery and drug monitoring.

    Science.gov (United States)

    Piel, Markus; Vernaleken, Ingo; Rösch, Frank

    2014-11-26

    Molecular imaging methods such as positron emission tomography (PET) are increasingly involved in the development of new drugs. Using radioactive tracers as imaging probes, PET allows the determination of the pharmacokinetic and pharmacodynamic properties of a drug candidate, via recording target engagement, the pattern of distribution, and metabolism. Because of the noninvasive nature and quantitative end point obtainable by molecular imaging, it seems inherently suited for the examination of a pharmaceutical's behavior in the brain. Molecular imaging, most especially PET, can therefore be a valuable tool in CNS drug research. In this Perspective, we present the basic principles of PET, the importance of appropriate tracer selection, the impact of improved radiopharmaceutical chemistry in radiotracer development, and the different roles that PET can fulfill in CNS drug research.

  12. Positron Emission Tomography: state of the art and future developments

    Science.gov (United States)

    Pizzichemi, M.

    2016-08-01

    Positron emission tomography (PET) plays a fundamental role in medical imaging, with a wide range of applications covering, among the others, oncology, neurology and cardiology. PET has undergone a steady technological evolution since its introduction in mid 20th century, from the development of 3D PET in the late 1980s, to the invention of PET/CT in the 1990s and more recently with the introduction of PET/MR scanners. The current research topics aiming to develop the next generation of PET scanners are summarized in this paper, focusing on the efforts to increase the sensitivity of the detectors, as long as improving their timing, spatial and energy resolutions, with the final goal of reducing the amount of radioactive dose received by the patients and the duration of the exams while improving at the same time the detectability of lesions.

  13. Temporoparietal cortex in aphasia. Evidence from positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Metter, E.J.; Hanson, W.R.; Jackson, C.A.; Kempler, D.; van Lancker, D.; Mazziotta, J.C.; Phelps, M.E. (National Institute of Aging, Baltimore, MD (USA))

    1990-11-01

    Forty-four aphasic patients were examined with (F18)-fluorodeoxyglucose positron emission tomography in a resting state to determine whether consistent glucose metabolic abnormalities were present. Ninety-seven percent of subjects showed metabolic abnormalities in the angular gyrus, 89% in the supramarginal gyrus, and 87% in the lateral and transverse superior temporal gyrus. Pearson product moment correlations were calculated between regional metabolic measures and performance on the Western Aphasia Battery. No significant correlations were found between the Western Aphasia Battery scores and right hemisphere metabolic measures. Most left hemisphere regions correlated with more than one score from the Western Aphasia Battery. Temporal but not frontal regions had significant correlations to the comprehension score. The left temporoparietal region was consistently affected in these subjects, suggesting that common features in the aphasias were caused by left temporoparietal dysfunction, while behavioral differences resulted from (1) the extent of temporoparietal changes, and (2) dysfunction elsewhere in the brain, particularly the left frontal and subcortical areas.

  14. Positron emission tomography / computerized tomography evaluation of primary Hodgkin's disease of liver.

    Science.gov (United States)

    Gota, V S; Purandare, N C; Gujral, S; Shah, S; Nair, R; Rangarajan, V

    2009-01-01

    Occurrence of primary Hodgkin's lymphoma (PHL) of the liver is extremely rare. We report on a case of a 60-year-old male who presented with liver mass and B-symptomatology. Hepatoma or hepatic metastasis from a gastrointestinal primary was initially suspected. Tumor markers like AFP, CEA, Total PSA, and CA-19.9 were within normal limits. Positron Emission Tomography / Computerized Tomography (PET/CT) revealed a large hepatic lesion and a nodal mass in the porta hepatis. A liver biopsy was consistent with Hodgkin's lymphoma. There was complete regression of the hepatic lesion and evidence of shrinkage of the nodal mass following four cycles of chemotherapy. 18F Fluro -de-oxy Glucose (FDG) PET / CT in this case helped in establishing a primary hepatic lymphoma by demonstrating the absence of pathologically hypermetabolic foci in any other nodes or organs. PET / CT scan is a useful adjunct to conventional imaging and histopathology, not only to establish the initial diagnosis, but also to monitor treatment response in PHL.

  15. Small-Animal Imaging Using Clinical Positron Emission Tomography/Computed Tomography and Super-Resolution

    Directory of Open Access Journals (Sweden)

    Frank P. DiFilippo

    2012-05-01

    Full Text Available Considering the high cost of dedicated small-animal positron emission tomography/computed tomography (PET/CT, an acceptable alternative in many situations might be clinical PET/CT. However, spatial resolution and image quality are of concern. The utility of clinical PET/CT for small-animal research and image quality improvements from super-resolution (spatial subsampling were investigated. National Electrical Manufacturers Association (NEMA NU 4 phantom and mouse data were acquired with a clinical PET/CT scanner, as both conventional static and stepped scans. Static scans were reconstructed with and without point spread function (PSF modeling. Stepped images were postprocessed with iterative deconvolution to produce super-resolution images. Image quality was markedly improved using the super-resolution technique, avoiding certain artifacts produced by PSF modeling. The 2 mm rod of the NU 4 phantom was visualized with high contrast, and the major structures of the mouse were well resolved. Although not a perfect substitute for a state-of-the-art small-animal PET/CT scanner, a clinical PET/CT scanner with super-resolution produces acceptable small-animal image quality for many preclinical research studies.

  16. Virtual positron emission tomography/computed tomography-bronchoscopy: possibilities, advantages and limitations of clinical application

    Energy Technology Data Exchange (ETDEWEB)

    Seemann, Marcus D. [University of Magdeburg, Department of Radiology and Nuclear Medicine, Magdeburg (Germany); Schaefer, Juergen F. [Eberhard-Karls University, Department of Diagnostic Radiology, Tuebingen (Germany); Englmeier, Karl-Hans [Institute of Medical Informatics, GSF-National Research Center for Environment and Health, Neuherberg (Germany)

    2007-03-15

    The aim of this study was to demonstrate the possibilities, advantages and limitations of virtual bronchoscopy using data sets from positron emission tomography (PET) and computed tomography (CT). Twelve consecutive patients with lung cancer underwent PET/CT. PET was performed with F-18-labelled 2-[fluorine-18]-fluoro-2-deoxy-D-glucose ({sup 18}F-FDG). The tracheobronchial system was segmented with a volume-growing algorithm, using the CT data sets, and visualized with a shaded-surface rendering method. The primary tumours and the lymph node metastases were segmented for virtual CT-bronchoscopy using the CT data set and for virtual PET/CT-bronchoscopy using the PET/CT data set. Virtual CT-bronchoscopy using the low-dose or diagnostic CT facilitates the detection of anatomical/morphological structure changes of the tracheobronchial system. Virtual PET/CT-bronchoscopy was superior to virtual CT-bronchoscopy in the detection of lymph node metastases (P=0.001), because it uses the CT information and the molecular/metabolic information from PET. Virtual PET/CT-bronchoscopy with a transparent colour-coded shaded-surface rendering model is expected to improve the diagnostic accuracy of identification and characterization of malignancies, assessment of tumour staging, differentiation of viable tumour tissue from atelectases and scars, verification of infections, evaluation of therapeutic response and detection of an early stage of recurrence that is not detectable or is misjudged in comparison with virtual CT-bronchoscopy. (orig.)

  17. Use of Positron Emission Tomography/Computed Tomography in Radiation Treatment Planning for Lung Cancer

    Directory of Open Access Journals (Sweden)

    Kezban Berberoğlu

    2016-06-01

    Full Text Available Radiotherapy (RT plays an important role in the treatment of lung cancer. Accurate diagnosis and staging are crucial in the delivery of RT with curative intent. Target miss can be prevented by accurate determination of tumor contours during RT planning. Currently, tumor contours are determined manually by computed tomography (CT during RT planning. This method leads to differences in delineation of tumor volume between users. Given the change in RT tools and methods due to rapidly developing technology, it is now more significant to accurately delineate the tumor tissue. F18 fluorodeoxyglucose positron emission tomography/CT (F18 FDG PET/CT has been established as an accurate method in correctly staging and detecting tumor dissemination in lung cancer. Since it provides both anatomic and biologic information, F18 FDG PET decreases interuser variability in tumor delineation. For instance, tumor volumes may be decreased as atelectasis and malignant tissue can be more accurately differentiated, as well as better evaluation of benign and malignant lymph nodes given the difference in FDG uptake. Using F18 FDG PET/CT, the radiation dose can be escalated without serious adverse effects in lung cancer. In this study, we evaluated the contribution of F18 FDG PET/CT for RT planning in lung cancer.

  18. Positron emission tomography/computer tomography in guidance of extrahepatic hepatocellular carcinoma metastasis management

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Hepatocellular carcinoma (HCC) is one of the most common primary cancers in the world. Surgery is the gold standard for treatment of patients with HCC. Recurrence and metastasis are the major obstacles to further improve the prognosis of HCC. Most recurrences are intrahepatic. However, 30% of the recurrences are extrahepatic. The role of resection in intrahepatic recurrences is widely accepted. The role of resection in extrahepatic HCC recurrence and metastasis is not well established. 18F fluorodeoxyglucose (18F-FDG) positron emission tomography/computer tomography (PET/CT) is useful in detecting distant metastasis from a variety of malignancies and shows superior accuracy to conventional imaging modalities in identification of intrahepatic and extrahepatic metastasis. We present one patient with one new isolated omental lymph node metastasis, who had a history of huge HCC resected six years ago. The metastatic focus was identified with 18 F-FDG PET/CT and resected. The follow-up revealed good prognosis with a long-term survival potential after resection of the omental lymphatic metastasis.

  19. Comparison of diffuse optical tomography of human breast with whole-body and breast-only positron emission tomography

    OpenAIRE

    Konecky, Soren D.; Choe, Regine; Corlu, Alper; Lee, Kijoon; Wiener, Rony; Srinivas, Shyam M.; Saffer, Janet R.; FREIFELDER, RICHARD; Karp, Joel S.; Hajjioui, Nassim; Azar, Fred; Yodh, Arjun G.

    2008-01-01

    We acquire and compare three-dimensional tomographic breast images of three females with suspicious masses using diffuse optical tomography (DOT) and positron emission tomography (PET). Co-registration of DOT and PET images was facilitated by a mutual information maximization algorithm. We also compared DOT and whole-body PET images of 14 patients with breast abnormalities. Positive correlations were found between total hemoglobin concentration and tissue scattering measured by DOT, and fluor...

  20. Fundamental studies of myocardial defect size quantification using positron emission tomography and single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Yoneyama, Tatsuya [Kanazawa Univ. (Japan). School of Medicine

    2001-04-01

    In Flurine-18 fluorodeoxyglucose ({sup 18}F-FDG) positron emission tomography (PET) acquisition, a transmission scan is usually performed before the PET tracer injection (cold transmission method), followed by a subsequent emission scan. However, this procedure is time consuming. An alternative approach, in which the transmission scan is performed after the emission scan (hot transmission method), would significantly reduce the time required for data acquisition. Recently, three-dimensional PET acquisition (3D PET) has become available. The counting sensitivity is much higher in 3D PET than in conventional two-dimensional PET (2D PET), resulting in a shorter acquisition time and reduced radiation exposure for the patient. On the other hand, {sup 18}F-FDG imaging using single photon emission computed tomography (SPECT), a more widely available method than PET, has emerged as an alternative to PET. The purpose of this study was to investigate the accuracy of measurement of myocardial defect sizes by these new techniques, using a chest phantom. Acquisitions were performed using an elliptical cylinder chest phantom. Plastic inserts, ranging in size from 2-60% of the myocardium (n=12), were used as simulated models of transmural myocardial infarction. Fluorine-18 was given into each part of the phantom. PET imaging with cold and hot transmission methods, 3D PET, and SPECT imaging were performed with different acquisition times and different radioisotope concentrations. All PET and SPECT data were analyzed using a semiquantitative polar map approach. Defect sizes were quantified using various cutoff thresholds, and were expressed as a percentage of the left ventricular myocardium. The PET and SPECT measurements were compared with the true defect sizes. Among the various cutoff levels tested, the mean absolute difference between the measured and true defect sizes was minimal at 50% of peak activity for both PET and SPECT. The PET measurements with the hot transmission

  1. Prognostic value of 18-fluorodeoxyglucose positron emission tomography-computed tomography in resectable colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Jang Eun Lee; Sang Woo Kim; Jin Su Kim; Kyu Yong Choi; Won Kyung Kang; Seong Taek Oh; Ie Ryung Yoo

    2012-01-01

    AIM:To assess the prognostic value of preoperative 18 fluorodeoxyglucose positron emission tomography (FDG-PET)/computed tomography (CT) in patients with resectable colorectal cancer.METHODS:One hundred sixty-three patients with resectable colorectal cancer who underwent FDG-PET/CT before surgery were included.Patient data including pathologic stage at presentation,histology,treatment,disease-free survival and the maximum standardized uptake value (SUVmax) of the primary tumor on FDGPET/CT were retrospectively analyzed.Median follow up duration was 756 (range,419-1355).The primary end point was disease-free survival.RESULTS:Twenty-five of 163 patients (15.3%) had recurrences.The median SUVmax values of the recurrence and no-recurrence groups were 8.9 (range,5-24) and 8.2 (range,0-23,P =0.998).Receiver operating characteristic (ROC) curve analysis showed no significant association between SUVmax and recurrence (area under the curve =0.5,P =0.998,95%CI:0.389-0.611).Because a statistically significant value was not found,SUVmax was dichotomized at its median of 8.6.The disease-free survival curve was analyzed using the median SUVmax (8.6) as the cut off.Univariate and multivariate analysis did not provide evidence that disease-free survival rates for the subgroups defined by the median SUVmax were significantly different (P =0.52,P =0.25).CONCLUSION:Our study suggests that the high FDG uptake of primary mass in resectable colorectal cancer doesn't have a significant relationship with tumor recurrence and disease-free survival.

  2. Diagnostic value for extrahepatic metastases of hepatocellular carcinoma in positron emission tomography/computed tomography scan

    Institute of Scientific and Technical Information of China (English)

    Ji Eun Lee; Jae Young Jang; Soung Won Jeong; Sae Hwan Lee; Sang Gyune Kim; Sang-Woo Cha; Young Seok Kim

    2012-01-01

    AIM:To evaluated the value of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) scan in diagnosis of hepatocellular carcinoma (HCC) and extrahepatic metastases.METHODS:A total of 138 patients with HCC who had both conventional imaging modalities and 18F-FDG PET/CT scan done between November 2006 and March 2011 were enrolled.Diagnostic value of each imaging modality for detection of extrahepatic metastases was evaluated.Clinical factors and tumor characteristics including PET imaging were analyzed as indicative factors for metastases by univariate and multivariate methods.RESULTS:The accuracy of chest CT was significantly superior compared with the accuracy of PET imaging for detecting lung metastases.The detection rate of metastatic pulmonary nodule ≥ 1 cm was 12/13(92.3%),when < 1 cm was 2/10 (20%) in PET imaging.The accuracy of PET imaging was significantly superior compared with the accuracy of bone scan for detecting bone metastases.In multivariate analysis,increased tumor size (≥ 5 cm) (P =0.042) and increased average standardized uptake value (SUV)uptake (P =0.028) were predictive factors for extrahepatic metastases.Isometabolic HCC in PET imaging was inversely correlated in multivariate analysis (P =0.035).According to the receiver operating characteristic curve,the optimal cutoff of average SUV to predict extrahepatic metastases was 3.4.CONCLUSION:18F-FDG PET/CT scan is invaluable for detection of lung metastases larger than 1 cm and bone metastases.Primary HCC having larger than 5 cm and increased average SUV uptake more than 3.4should be considered for extrahepatic metastases.

  3. Pitfalls in Positron Emission Tomography/Computed Tomography Imaging: Causes and Their Classifications

    Institute of Scientific and Technical Information of China (English)

    Tian-ran Li; Jia-he Tian; Hui Wang; Zi-qian Chen; Chun-lei Zhao

    2009-01-01

    Objective To describe the pitfalls in positron emission tomography/computed tomography (PET/CT) imaging and classify them according to the principles of their generation. Methods We summarized retrospectively the 18F-fluorodeoxyglucose (FDP) PET/CT imaging pitfalls through reviewing the PET/CT images of 872 patients. The pitfalls were divided into artifacts and infrequent physiological uptake, and the artifacts were further classified according to their causes. Meanwhile, we calculated the incidences of various pitfalls. Whether the PET/CT pitfalls influenced the diagnostic decision was analyzed. The appearances of pitfalls in PET were also described. Results Pitfalls could be found in PET/CT images of 684 (78.4%) patients. Artifacts were found in 664 (76.15%) patients, and could be classified into self-factor artifacts and equipment- or technology- related artifacts. Among self-factor artifacts, respiratory motion (57.5%), postprandial or hyperglycemia artifacts (2.41%), and metal or high density matter artifacts (1.38%) were frequent. As for equipment- or technology-related factors, injection point outleakage or radiotracer contamination (13.88%) and truncation artifacts (1.83%) were most common ones. Infrequent physiological FDG uptakes, including fatty uptake, endometrial uptake, and bilateral breast feeding period uptake, were found in 20 (2.29%) patients. Among all pitfalls, the artifacts in 92 (13.4%) patients and infrequent physiological uptakes in 6 (0.88%) patients affected the diagnostic results. Artifact images in PET could be described as hot or cold area and the images of infrequent physiological uptake were always shown as hot area. Conclusions The incidence of pitfall in PET/CT imaging was high and the causes of pitfalls are various. Among all causes that artifacts generated, respiratory motion is the most common. Some pitfalls may disturb clinical physicians' decision, so it is important to recognize artifacts and physiological uptake, and

  4. Relationship of computed tomography perfusion and positron emission tomography to tumour progression in malignant glioma

    Energy Technology Data Exchange (ETDEWEB)

    Yeung, Timothy P C [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Robarts Research Institute, The University of Western Ontario, Ontario, Canada, N6A 5B7 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Yartsev, Slav [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Lee, Ting-Yim [Robarts Research Institute, The University of Western Ontario, Ontario, Canada, N6A 5B7 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Department of Medical Imaging, The University of Western Ontario, London Health Sciences Centre, Victoria Hospital, Ontario, Canada, N6A 5W9 (Australia); Lawson Health Research Institute, St. Joseph' s Health Care London, Ontario, Canada, N6A 4V2 (Canada); Wong, Eugene [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Department of Physics and Astronomy, The University of Western Ontario, Ontario, Canada, N6A 3K7 (Canada); He, Wenqing [Department of Statistical and Actuarial Sciences, The University of Western Ontario, Ontario, Canada, N6A 5B7 (Canada); Fisher, Barbara; VanderSpek, Lauren L [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Macdonald, David [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Department of Clinical Neurological Sciences, The University of Western Ontario, London Health Sciences Centre, University Hospital, Ontario, Canada, N6A 5A5 (Canada); Bauman, Glenn, E-mail: glenn.bauman@lhsc.on.ca [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada)

    2014-02-15

    Introduction: This study aimed to explore the potential for computed tomography (CT) perfusion and 18-Fluorodeoxyglucose positron emission tomography (FDG-PET) in predicting sites of future progressive tumour on a voxel-by-voxel basis after radiotherapy and chemotherapy. Methods: Ten patients underwent pre-radiotherapy magnetic resonance (MR), FDG-PET and CT perfusion near the end of radiotherapy and repeated post-radiotherapy follow-up MR scans. The relationships between these images and tumour progression were assessed using logistic regression. Cross-validation with receiver operating characteristic (ROC) analysis was used to assess the value of these images in predicting sites of tumour progression. Results: Pre-radiotherapy MR-defined gross tumour; near-end-of-radiotherapy CT-defined enhancing lesion; CT perfusion blood flow (BF), blood volume (BV) and permeability-surface area (PS) product; FDG-PET standard uptake value (SUV); and SUV:BF showed significant associations with tumour progression on follow-up MR imaging (P < 0.0001). The mean sensitivity (±standard deviation), specificity and area under the ROC curve (AUC) of PS were 0.64 ± 0.15, 0.74 ± 0.07 and 0.72 ± 0.12 respectively. This mean AUC was higher than that of the pre-radiotherapy MR-defined gross tumour and near-end-of-radiotherapy CT-defined enhancing lesion (both AUCs = 0.6 ± 0.1, P ≤ 0.03). The multivariate model using BF, BV, PS and SUV had a mean AUC of 0.8 ± 0.1, but this was not significantly higher than the PS only model. Conclusion: PS is the single best predictor of tumour progression when compared to other parameters, but voxel-based prediction based on logistic regression had modest sensitivity and specificity.

  5. Motion management in positron emission tomography/computed tomography for radiation treatment planning.

    Science.gov (United States)

    Bettinardi, Valentino; Picchio, Maria; Di Muzio, Nadia; Gilardi, Maria Carla

    2012-09-01

    Hybrid positron emission tomography (PET)/computed tomography (CT) scanners combine, in a unique gantry, 2 of the most important diagnostic imaging systems, a CT and a PET tomograph, enabling anatomical (CT) and functional (PET) studies to be performed in a single study session. Furthermore, as the 2 scanners use the same spatial coordinate system, the reconstructed CT and PET images are spatially co-registered, allowing an accurate localization of the functional signal over the corresponding anatomical structure. This peculiarity of the hybrid PET/CT system results in improved tumor characterization for oncological applications, and more recently, it was found to be also useful for target volume definition (TVD) and treatment planning in radiotherapy (RT) applications. In fact, the use of combined PET/CT information has been shown to improve the RT treatment plan when compared with that obtained by a CT alone. A limiting factor to the accuracy of TVD by PET/CT is organ and tumor motion, which is mainly due to patient respiration. In fact, respiratory motion has a degrading effect on PET/CT image quality, and this is also critical for TVD, as it can lead to possible tumor missing or undertreatment. Thus, the management of respiratory motion is becoming an increasingly essential component in RT treatment planning; indeed, it has been recognized that the use of personalized motion information can improve TVD and, consequently, permit increased tumor dosage while sparing surrounding healthy tissues and organs at risk. This review describes the methods used for motion management in PET/CT for radiation treatment planning. The article covers the following: (1) problems caused by organ and lesion motion owing to respiration, and the artifacts generated on CT, PET, and PET/CT images; (2) data acquisition and processing techniques used to manage respiratory motion in PET/CT studies; and (3) the use of personalized motion information for TVD and radiation treatment planning.

  6. Positron Emission Tomography Detector Development for Plant Biology

    Energy Technology Data Exchange (ETDEWEB)

    Weisenberger, A G; McKisson, J; Stolin, A; Zorn, C; Howell, C R; Crowell, A S; Reid, C D; Majewski, S

    2010-01-01

    There are opportunities for the development of new tools to advance plant biology research through the use of radionuclides. Thomas Jefferson National Accelerator Facility, Duke University, West Virginia University and the University of Maryland are collaborating on the development of radionuclide imaging technologies to facilitate plant biology research. Biological research into optimizing plant productivity under various environmental constraints, biofuel and carbon sequestration research are areas that could potentially benefit from new imaging technologies. Using 11CO2 tracers, the investigators at Triangle University Nuclear Laboratory / Duke University Phytotron are currently researching the dynamical responses of plants to environmental changes forecasted from increasing greenhouse trace gases involved in global change. The biological research primary focus is to investigate the impact of elevated atmospheric CO2 and nutrients limitation on carbon and nitrogen dynamics in plants. We report here on preliminary results of 11CO2 plant imaging experiments involving barley plants using Jefferson Lab dual planar positron emission tomography detectors to image 11CO2 in live barley plants. New detector designs will be developed based on the preliminary studies reported here and further planned.

  7. Brain single photon emission computed tomography in neonates

    Energy Technology Data Exchange (ETDEWEB)

    Denays, R.; Van Pachterbeke, T.; Tondeur, M.; Spehl, M.; Toppet, V.; Ham, H.; Piepsz, A.; Rubinstein, M.; Nol, P.H.; Haumont, D. (Free Universities of Brussels (Belgium))

    1989-08-01

    This study was designed to rate the clinical value of ({sup 123}I)iodoamphetamine (IMP) or ({sup 99m}Tc) hexamethyl propylene amine oxyme (HM-PAO) brain single photon emission computed tomography (SPECT) in neonates, especially in those likely to develop cerebral palsy. The results showed that SPECT abnormalities were congruent in most cases with structural lesions demonstrated by ultrasonography. However, mild bilateral ventricular dilatation and bilateral subependymal porencephalic cysts diagnosed by ultrasound were not associated with an abnormal SPECT finding. In contrast, some cortical periventricular and sylvian lesions and all the parasagittal lesions well visualized in SPECT studies were not diagnosed by ultrasound scans. In neonates with subependymal and/or intraventricular hemorrhage the existence of a parenchymal abnormality was only diagnosed by SPECT. These results indicate that ({sup 123}I)IMP or ({sup 99m}Tc)HM-PAO brain SPECT shows a potential clinical value as the neurodevelopmental outcome is clearly related to the site, the extent, and the number of cerebral lesions. Long-term clinical follow-up is, however, mandatory in order to define which SPECT abnormality is associated with neurologic deficit.

  8. The next generation of positron emission tomography radiopharmaceuticals in oncology.

    Science.gov (United States)

    Rice, Samuel L; Roney, Celeste A; Daumar, Pierre; Lewis, Jason S

    2011-07-01

    Although (18)F-fluorodeoxyglucose ((18)F-FDG) is still the most widely used positron emission tomography (PET) radiotracer, there are a few well-known limitations to its use. The last decade has seen the development of new PET probes for in vivo visualization of specific molecular targets, along with important technical advances in the production of positron-emitting radionuclides and their related labeling methods. As such, a broad range of new PET tracers are in preclinical development or have recently entered clinical trials. The topics covered in this review include labeling methods, biological targets, and the most recent preclinical or clinical data of some of the next generation of PET radiopharmaceuticals. This review, which is by no means exhaustive, has been separated into sections related to the PET radionuclide used for radiolabeling: fluorine-18, for the labeling of agents such as FACBC, FDHT, choline, and Galacto-RGD; carbon-11, for the labeling of choline; gallium-68, for the labeling of peptides such as DOTATOC and bombesin analogs; and the long-lived radionuclides iodine-124 and zirconium-89 for the labeling of monoclonal antibodies cG250, and J591 and trastuzumab, respectively.

  9. Epithelioid sarcoma with muscle metastasis detected by positron emission tomography

    Directory of Open Access Journals (Sweden)

    Oya Masafumi

    2008-08-01

    Full Text Available Abstract Background Epithelioid sarcoma is an uncommon high-grade sarcoma, mostly involving the extremities. Case presentation A 33-year-old man was referred to our institute with a diagnosis of Volkmann's contracture with the symptom of flexion contracture of the fingers associated with swelling in his left forearm. Magnetic resonance imaging (MRI showed abnormal signal intensity, comprising iso-signal intensity on T1- and high-signal intensity on T2-weighted images surrounding the flexor tendons in the forearm. Diagnosis of epithelioid sarcoma was made by open biopsy, and amputation at the upper arm was then undertaken. [18F]-2-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET detected multiple lesions with an increased uptake in the right neck, the bilateral upper arms and the right thigh, as well as in the left axillary lymph nodes, with maximum standardized uptake value (SUVmax ranging from 2.0 to 5.5 g/ml. Magnetic resonance imaging confirmed that there was a lesion within the right thigh muscle which was suggestive of metastasis, even though the lesion was occult clinically. Conclusion Increased uptake on FDG-PET might be representative of epithelioid sarcoma, and for this reason FDG-PET may be useful for detecting metastasis. Muscle metastasis is not well documented in epithelioid sarcoma. Accordingly, the frequency of muscle metastasis, including occult metastasis, needs to be further analyzed.

  10. Characterization of time resolved photodetector systems for Positron Emission Tomography

    CERN Document Server

    Powolny, François

    The main topic of this work is the study of detector systems composed of a scintillator, a photodetector and readout electronics, for Positron Emission Tomography (PET). In particular, the timing properties of such detector systems are studied. The first idea is to take advantage of the good timing properties of the NINO chip, which is a fast preamplifier-discriminator developed for the ALICE Time of flight detector at CERN. This chip uses a time over threshold technique that is to be applied for the first time in medical imaging applications. A unique feature of this technique is that it delivers both timing and energy information with a single digital pulse, the time stamp with the rising edge and the energy from the pulse width. This entails substantial simplification of the entire readout architecture of a tomograph. The scintillator chosen in the detector system is LSO. Crystals of 2x2x10mm3 were used. For the photodetector, APDs were first used, and were then replaced by SiPMs to make use of their highe...

  11. European health telematics networks for positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kontaxakis, George [Universidad Politecnica de Madrid, ETSI Telecomunicacion, Madrid 28040 (Spain)]. E-mail: g.kontaxakis@upm.es; Pozo, Miguel Angel [Centro PET Complutense, Madrid 28040 (Spain); Universidad Complutense de Madrid, Instituto Pluridisciplinar, Madrid 28040 (Spain); Ohl, Roland [MedCom Gesellschaft fuer medizinische Bildverarbeitung mbH, Darmstadt 64283 (Germany); Visvikis, Dimitris [U650 INSERM, Lab. du Traitement de L' Information Medicale, University of Brest Occidentale, CHU Morvan, Brest 29609 (France); Sachpazidis, Ilias [Fraunhofer Institute for Computer Graphics, Darmstadt 64283 (Germany); Ortega, Fernando [Fundacion Instituto Valenciano de Oncologia, Valencia 46009 (Spain); Guerra, Pedro [Universidad Politecnica de Madrid, ETSI Telecomunicacion, Madrid 28040 (Spain); Cheze-Le Rest, Catherine [Dept. Medicine Nucleaire, CHU Morvan, Brest 29609 (France); Selby, Peter [MedCom Gesellschaft fuer medizinische Bildverarbeitung mbH, Darmstadt 64283 (Germany); Pan, Leyun [German Cancer Research Centre, Clinical Cooperation Unit Nuclear Medicine, Heidelberg 69120 (Germany); Diaz, Javier [Fundacion Instituto Valenciano de Oncologia, Valencia 46009 (Spain); Dimitrakopoulou-Strauss, Antonia [German Cancer Research Centre, Clinical Cooperation Unit Nuclear Medicine, Heidelberg 69120 (Germany); Santos, Andres [Universidad Politecnica de Madrid, ETSI Telecomunicacion, Madrid 28040 (Spain); Strauss, Ludwig [German Cancer Research Centre, Clinical Cooperation Unit Nuclear Medicine, Heidelberg 69120 (Germany); Sakas, Georgios [MedCom Gesellschaft fuer medizinische Bildverarbeitung mbH, Darmstadt 64283 (Germany); Fraunhofer Institute for Computer Graphics, Darmstadt 64283 (Germany)

    2006-12-20

    A pilot network of positron emission tomography centers across Europe has been setup employing telemedicine services. The primary aim is to bring all PET centers in Europe (and beyond) closer, by integrating advanced medical imaging technology and health telematics networks applications into a single, easy to operate health telematics platform, which allows secure transmission of medical data via a variety of telecommunications channels and fosters the cooperation between professionals in the field. The platform runs on PCs with Windows 2000/XP and incorporates advanced techniques for image visualization, analysis and fusion. The communication between two connected workstations is based on a TCP/IP connection secured by secure socket layers and virtual private network or jabber protocols. A teleconsultation can be online (with both physicians physically present) or offline (via transmission of messages which contain image data and other information). An interface sharing protocol enables online teleconsultations even over low bandwidth connections. This initiative promotes the cooperation and improved communication between nuclear medicine professionals, offering options for second opinion and training. It permits physicians to remotely consult patient data, even if they are away from the physical examination site.

  12. Positron Emission Tomography Application to Drug Development and Research

    Science.gov (United States)

    Salvadori, Piero A.

    The research for the identification and development of new drugs represents a very complex process implying long times and massive investments. This process was not able to parallel the rate of discoveries made in the field of genomic and molecular biology and a gap created between demand of new drugs and the ability of pharmaceutical companies to select good candidates. Positron Emission Tomography, among the different Molecular Imaging modalities, could represent a new tool for the early assessment and screening of new drug candidates and, due to its physical performances and the characteristics of positron-labeled tracers, gain the role of "Biomarker" accepted by the Companies and the Regulatory Bodies of Drug Agencies. To fulfil this task PET has to exploit all of its special features such as data absolute quantification and modelling, high spatial resolution and dynamic imaging. Relevant efforts need to be directed to the careful design and validation of experimental protocols with the main goal of achieving consistency in multi- centric trials.

  13. Markerless motion tracking of awake animals in positron emission tomography.

    Science.gov (United States)

    Kyme, Andre; Se, Stephen; Meikle, Steven; Angelis, Georgios; Ryder, Will; Popovic, Kata; Yatigammana, Dylan; Fulton, Roger

    2014-11-01

    Noninvasive functional imaging of awake, unrestrained small animals using motion-compensation removes the need for anesthetics and enables an animal's behavioral response to stimuli or administered drugs to be studied concurrently with imaging. While the feasibility of motion-compensated radiotracer imaging of awake rodents using marker-based optical motion tracking has been shown, markerless motion tracking would avoid the risk of marker detachment, streamline the experimental workflow, and potentially provide more accurate pose estimates over a greater range of motion. We have developed a stereoscopic tracking system which relies on native features on the head to estimate motion. Features are detected and matched across multiple camera views to accumulate a database of head landmarks and pose is estimated based on 3D-2D registration of the landmarks to features in each image. Pose estimates of a taxidermal rat head phantom undergoing realistic rat head motion via robot control had a root mean square error of 0.15 and 1.8 mm using markerless and marker-based motion tracking, respectively. Markerless motion tracking also led to an appreciable reduction in motion artifacts in motion-compensated positron emission tomography imaging of a live, unanesthetized rat. The results suggest that further improvements in live subjects are likely if nonrigid features are discriminated robustly and excluded from the pose estimation process.

  14. FPGA-Based Pulse Parameter Discovery for Positron Emission Tomography.

    Science.gov (United States)

    Haselman, Michael; Hauck, Scott; Lewellen, Thomas K; Miyaoka, Robert S

    2009-10-24

    Modern Field Programmable Gate Arrays (FPGAs) are capable of performing complex digital signal processing algorithms with clock rates well above 100MHz. This, combined with FPGA's low expense and ease of use make them an ideal technology for a data acquisition system for a positron emission tomography (PET) scanner. The University of Washington is producing a series of high-resolution, small-animal PET scanners that utilize FPGAs as the core of the front-end electronics. For these next generation scanners, functions that are typically performed in dedicated circuits, or offline, are being migrated to the FPGA. This will not only simplify the electronics, but the features of modern FPGAs can be utilizes to add significant signal processing power to produce higher resolution images. In this paper we report how we utilize the reconfigurable property of an FPGA to self-calibrate itself to determine pulse parameters necessary for some of the pulse processing steps. Specifically, we show how the FPGA can generate a reference pulse based on actual pulse data instead of a model. We also report how other properties of the photodetector pulse (baseline, pulse length, average pulse energy and event triggers) can be determined automatically by the FPGA.

  15. [Methods and clinical applications of positron emission tomography in endocrinology].

    Science.gov (United States)

    De Landsheere, C; Lamotte, D

    1990-01-01

    Positron emission tomography (PET) allows to detect in coincidence photons issued from annihilation between positrons and electrons nearby situated. Tomographic detection (plane by plane) and tomographic reconstruction will lead to the quantitation of radioactive distribution per voxel, in the organ of interest. Recent tomographs can acquire simultaneously several transaxial slices, with a high sensitivity and a spatial resolution of 3-5 mm. Commonly used positron emitters have a short half-life: 2, 10, 20 and 110 min for 150, 13N, 11C and 18F, respectively. The use of these isotopes requires on line production of radionuclides and synthesis of selected molecules. In endocrinology, PET allows among others to study noninvasively the receptor density of hormone-dependent neoplasms such as breast, uterus, prostate tumors and prolactinomas. These last tumors represent a particular entity because of several combined characteristics: high turnover rate of amino acids, high density of dopaminergic receptors and response to bromocriptine (analogue of dopamine inhibiting the secretion of prolactin) in relation to the level of receptors. Because PET permits to evaluate the density of dopaminergic receptors and the metabolism of amino acids, theoretical response of the prolactinoma to bromocriptine can be predicted, the achieved therapeutic efficacy can be estimated and the long-term follow up of tumor growth can be assessed. This example illustrates the clinical value of PET in endocrinology.

  16. Computed tomography angiography and perfusion to assess coronary artery stenosis causing perfusion defects by single photon emission computed tomography

    DEFF Research Database (Denmark)

    Rochitte, Carlos E; George, Richard T; Chen, Marcus Y

    2014-01-01

    AIMS: To evaluate the diagnostic power of integrating the results of computed tomography angiography (CTA) and CT myocardial perfusion (CTP) to identify coronary artery disease (CAD) defined as a flow limiting coronary artery stenosis causing a perfusion defect by single photon emission computed ...

  17. Positron emission tomography for serial imaging of the contused adult rat spinal cord.

    NARCIS (Netherlands)

    Nandoe, R.D.S.; Yu, J.; Seidel, J.; Rahiem, S.T.; Hurtado, A.; Tsui, B.M.; Grotenhuis, J.A.; Pomper, M.G.; Oudega, M.

    2010-01-01

    We investigated whether small-animal positron emission tomography (PET) could be used in combination with computed tomography (CT) imaging techniques for longitudinal monitoring of the injured spinal cord. In adult female Sprague-Dawley rats (n = 6), the ninth thoracic (T9) spinal cord segment was e

  18. Predictive value of early F-18-fluoro-deoxyglucose positron emission tomography in chemosensitive relapsed lymphoma

    NARCIS (Netherlands)

    Schot, B; van Imhoff, G; Pruim, J; Sluiter, W; Vaalburg, W; Vellenga, E

    2003-01-01

    F-18-fluoro-deoxyglucose (FDG) positron emission tomography (PET) might be a better tool than computerized tomography (CT) in predicting long-term treatment outcome in patients with relapsed chemosensitive lymphoma who are candidates for autologous stem cell transplantation (ASCT). We studied patien

  19. Imaging Atherosclerosis with Hybrid Positron Emission Tomography/Magnetic Resonance Imaging

    DEFF Research Database (Denmark)

    Ripa, Rasmus Sejersten; Kjær, Andreas

    2015-01-01

    Noninvasive imaging of atherosclerosis could potentially move patient management towards individualized triage, treatment, and followup. The newly introduced combined positron emission tomography (PET) and magnetic resonance imaging (MRI) system could emerge as a key player in this context. Both ...

  20. 77 FR 71802 - Guidance on Investigational New Drug Applications for Positron Emission Tomography Drugs...

    Science.gov (United States)

    2012-12-04

    ... HUMAN SERVICES Food and Drug Administration Guidance on Investigational New Drug Applications for... ``Investigational New Drug Applications for Positron Emission Tomography (PET) Drugs.'' The guidance is intended to assist manufacturers of PET drugs in submitting investigational new drug applications (INDs)....

  1. Central benzodiazepine receptor imaging and quantitation with single photon emission computerised tomography

    DEFF Research Database (Denmark)

    Okocha, C I; Kapczinski, F; Lassen, N

    1995-01-01

    This review discusses the current use of single photon emission computerised tomography (SPECT) for central benzodiazepine receptor imaging and quantitation. The general principles underlying SPECT imaging and receptor quantitation methods such as the kinetic, pseudo-equilibrium and steady...

  2. Endocrine radionuclide scintigraphy with fusion single photon emission computed tomography/computed tomography

    Institute of Scientific and Technical Information of China (English)

    Ka-Kit Wong; Arpit Gandhi; Benjamin L Viglianti; Lorraine M Fig; Domenico Rubello; Milton D Gross

    2016-01-01

    AIM: To review the benefits of single photon emission computed tomography(SPECT)/computed tomography(CT) hybrid imaging for diagnosis of various endocrine disorders.METHODS: We performed MEDLINE and Pub Med searches using the terms: "SPECT/CT"; "functional anatomic mapping"; "transmission emission tomography"; "parathyroid adenoma"; "thyroid cancer"; "neuroendocrine tumor"; "adrenal"; "pheochromocytoma"; "paraganglioma"; in order to identify relevant articles published in English during the years 2003 to 2015. Reference lists from the articles were reviewed to identify additional pertinent articles. Retrieved manuscripts(case reports, reviews, meta-analyses and abstracts) concerning the application of SPECT/CT to endocrine imaging were analyzed to provide a descriptive synthesis of the utility of this technology.RESULTS: The emergence of hybrid SPECT/CT camera technology now allows simultaneous acquisition of combined multi-modality imaging, with seamless fusion of three-dimensional volume datasets. The usefulness of combining functional information to depict the biodistribution of radiotracers that map cellular processes of the endocrine system and tumors of endocrine origin, with anatomy derived from CT, has improved the diagnostic capability of scintigraphy for a range of disorders of endocrine gland function. The literature describes benefits of SPECT/CT for 99mTc-sestamibi parathyroid scintigraphy and 99mTc-pertechnetate thyroid scintigraphy, 123I- or 131I-radioiodine for staging of differentiated thyroid carcinoma, 111In- and 99mTclabeled somatostatin receptor analogues for detection of neuroendocrine tumors, 131I-norcholesterol(NP-59) scans for assessment of adrenal cortical hyperfunction, and 123I- or 131I-metaiodobenzylguanidine imaging for evaluation of pheochromocytoma and paraganglioma.CONCLUSION: SPECT/CT exploits the synergism between the functional information from radiopharmaceutical imaging and anatomy from CT, translating to

  3. Physiologic positron emission tomography/CT imaging of an integrated orbital implant.

    Science.gov (United States)

    Graue, Gerardo F; Finger, Paul T

    2012-01-01

    A 46-year-old woman with a T4N0M0 choroidal melanoma was staged for metastatic disease with whole-body positron emission tomography/CT imaging. She underwent enucleation of the right eye and placement of a 20-mm MEDPOR spherical implant. Four months after surgery, follow-up positron emission tomography/CT imaging revealed physiologic metabolic activity in the MEDPOR implant with no evidence of orbital melanoma or chronic inflammation.

  4. Contrast-enhanced fluorodeoxyglucose positron emission tomography/contrast-enhanced computed tomography in mediastinal T-cell lymphoma with superior vena cava syndrome.

    Science.gov (United States)

    Santhosh, Sampath; Gorla, Arun Kumar Reddy; Bhattacharya, Anish; Varma, Subhash Chander; Mittal, Bhagwant Rai

    2016-01-01

    Positron emission tomography-computed tomography (PET/CT) is a routine investigation for the staging of lymphomas. Contrast-enhanced computed tomography is mandatory whenever parenchymal lesions, especially in the liver and spleen are suspected. We report a rare case of primary mediastinal T-cell lymphoma evaluated with contrast-enhanced PET/CT that showed features of superior vena cava syndrome.

  5. Alcohol ADME in primates studied with positron emission tomography.

    Directory of Open Access Journals (Sweden)

    Zizhong Li

    Full Text Available BACKGROUND AND PURPOSE: The sensitivity to the intoxicating effects of alcohol as well as its adverse medical consequences differ markedly among individuals, which reflects in part differences in alcohol's absorption, distribution, metabolism, and elimination (ADME properties. The ADME of alcohol in the body and its relationship with alcohol's brain bioavailability, however, is not well understood. EXPERIMENTAL APPROACH: The ADME of C-11 labeled alcohol, CH(3 (11CH(2OH, 1 and C-11 and deuterium dual labeled alcohol, CH(3 (11CD(2OH, 2 in baboons was compared based on the principle that C-D bond is stronger than C-H bond, thus the reaction is slower if C-D bond breaking occurs in a rate-determining metabolic step. The following ADME parameters in peripheral organs and brain were derived from time activity curve (TAC of positron emission tomography (PET scans: peak uptake (C(max; peak uptake time (T(max, half-life of peak uptake (T(1/2, the area under the curve (AUC(60 min, and the residue uptake (C(60 min. KEY RESULTS: For 1 the highest uptake occurred in the kidney whereas for 2 it occurred in the liver. A deuterium isotope effect was observed in the kidneys in both animals studied and in the liver of one animal but not the other. The highest uptake for 1 and 2 in the brain was in striatum and cerebellum but 2 had higher uptake than 1 in all brain regions most evidently in thalamus and cingulate. Alcohol's brain uptake was significantly higher when given intravenously than when given orally and also when the animal was pretreated with a pharmacological dose of alcohol. CONCLUSION AND IMPLICATIONS: The study shows that alcohol metabolism in peripheral organs had a large effect on alcohol's brain bioavailability. This study sets the stage for clinical investigation on how genetics, gender and alcohol abuse affect alcohol's ADME and its relationship to intoxication and medical consequences.

  6. Proceedings of clinical SPECT (single photon emission computed tomography) symposium

    Energy Technology Data Exchange (ETDEWEB)

    1986-09-01

    It has been five years since the last in-depth American College of Nuclear Physicians/Society of Nuclear Medicine Symposium on the subject of single photon emission computed tomography (SPECT) was held. Because this subject was nominated as the single most desired topic we have selected SPECT imaging as the basis for this year's program. The objectives of this symposium are to survey the progress of SPECT clinical applications that have taken place over the last five years and to provide practical and timely guidelines to users of SPECT so that this exciting imaging modality can be fully integrated into the evaluation of pathologic processes. The first half was devoted to a consideration of technical factors important in SPECT acquisition and the second half was devoted to those organ systems about which sufficient clinical SPECT imaging data are available. With respect to the technical aspect of the program we have selected the key areas which demand awareness and attention in order to make SPECT operational in clinical practice. These include selection of equipment, details of uniformity correction, utilization of phantoms for equipment acceptance and quality assurance, the major aspect of algorithms, an understanding of filtered back projection and appropriate choice of filters and an awareness of the most commonly generated artifacts and how to recognize them. With respect to the acquisition and interpretation of organ images, the faculty will present information on the major aspects of hepatic, brain, cardiac, skeletal, and immunologic imaging techniques. Individual papers are processed separately for the data base. (TEM)

  7. PDE regularization for Bayesian reconstruction of emission tomography

    Science.gov (United States)

    Wang, Zhentian; Zhang, Li; Xing, Yuxiang; Zhao, Ziran

    2008-03-01

    The aim of the present study is to investigate a type of Bayesian reconstruction which utilizes partial differential equations (PDE) image models as regularization. PDE image models are widely used in image restoration and segmentation. In a PDE model, the image can be viewed as the solution of an evolutionary differential equation. The variation of the image can be regard as a descent of an energy function, which entitles us to use PDE models in Bayesian reconstruction. In this paper, two PDE models called anisotropic diffusion are studied. Both of them have the characteristics of edge-preserving and denoising like the popular median root prior (MRP). We use PDE regularization with an Ordered Subsets accelerated Bayesian one step late (OSL) reconstruction algorithm for emission tomography. The OS accelerated OSL algorithm is more practical than a non-accelerated one. The proposed algorithm is called OSEM-PDE. We validated the OSEM-PDE using a Zubal phantom in numerical experiments with attenuation correction and quantum noise considered, and the results are compared with OSEM and an OS version of MRP (OSEM-MRP) reconstruction. OSEM-PDE shows better results both in bias and variance. The reconstruction images are smoother and have sharper edges, thus are more applicable for post processing such as segmentation. We validate this using a k-means segmentation algorithm. The classic OSEM is not convergent especially in noisy condition. However, in our experiment, OSEM-PDE can benefit from OS acceleration and keep stable and convergent while OSEM-MRP failed to converge.

  8. Simulation of emission tomography using grid middleware for distributed computing.

    Science.gov (United States)

    Thomason, M G; Longton, R F; Gregor, J; Smith, G T; Hutson, R K

    2004-09-01

    SimSET is Monte Carlo simulation software for emission tomography. This paper describes a simple but effective scheme for parallel execution of SimSET using NetSolve, a client-server system for distributed computation. NetSolve (version 1.4.1) is "grid middleware" which enables a user (the client) to run specific computations remotely and simultaneously on a grid of networked computers (the servers). Since the servers do not have to be identical machines, computation may take place in a heterogeneous environment. To take advantage of diversity in machines and their workloads, a client-side scheduler was implemented for the Monte Carlo simulation. The scheduler partitions the total decay events by taking into account the inherent compute-speeds and recent average workloads, i.e., the scheduler assigns more decay events to processors expected to give faster service and fewer decay events to those expected to give slower service. When compute-speeds and sustained workloads are taken into account, the speed-up is essentially linear in the number of equivalent "maximum-service" processors. One modification in the SimSET code (version 2.6.2.3) was made to ensure that the total number of decay events specified by the user is maintained in the distributed simulation. No other modifications in the standard SimSET code were made. Each processor runs complete SimSET code for its assignment of decay events, independently of others running simultaneously. Empirical results are reported for simulation of a clinical-quality lung perfusion study.

  9. Noninvasive imaging of islet grafts using positron-emission tomography

    Science.gov (United States)

    Lu, Yuxin; Dang, Hoa; Middleton, Blake; Zhang, Zesong; Washburn, Lorraine; Stout, David B.; Campbell-Thompson, Martha; Atkinson, Mark A.; Phelps, Michael; Gambhir, Sanjiv Sam; Tian, Jide; Kaufman, Daniel L.

    2006-07-01

    Islet transplantation offers a potential therapy to restore glucose homeostasis in type 1 diabetes patients. However, islet transplantation is not routinely successful because most islet recipients gradually lose graft function. Furthermore, serological markers of islet function are insensitive to islet loss until the latter stages of islet graft rejection. A noninvasive method of monitoring islet grafts would aid in the assessment of islet graft survival and the evaluation of interventions designed to prolong graft survival. Here, we show that recombinant adenovirus can engineer isolated islets to express a positron-emission tomography (PET) reporter gene and that these islets can be repeatedly imaged by using microPET after transplantation into mice. The magnitude of signal from engineered islets implanted into the axillary cavity was directly related to the implanted islet mass. PET signals attenuated over the following weeks because of the transient nature of adenovirus-mediated gene expression. Because the liver is the preferred site for islet implantation in humans, we also tested whether islets could be imaged after transfusion into the mouse liver. Control studies revealed that both intrahepatic islet transplantation and hyperglycemia altered the biodistribution kinetics of the PET probe systemically. Although transplanted islets were dispersed throughout the liver, clear signals from the liver region of mice receiving PET reporter-expressing islets were detectable for several weeks. Viral transduction, PET reporter expression, and repeated microPET imaging had no apparent deleterious effects on islet function after implantation. These studies lay a foundation for noninvasive quantitative assessments of islet graft survival using PET. diabetes | transplantation

  10. Budget impact from the incorporation of positron emission tomography – computed tomography for staging lung cancers

    Directory of Open Access Journals (Sweden)

    Aline Navega Biz

    2015-01-01

    Full Text Available OBJECTIVE To estimate the budget impact from the incorporation of positron emission tomography (PET in mediastinal and distant staging of non-small cell lung cancer.METHODS The estimates were calculated by the epidemiological method for years 2014 to 2018. Nation-wide data were used about the incidence; data on distribution of the disease´s prevalence and on the technologies’ accuracy were from the literature; data regarding involved costs were taken from a micro-costing study and from Brazilian Unified Health System (SUS database. Two strategies for using PET were analyzed: the offer to all newly-diagnosed patients, and the restricted offer to the ones who had negative results in previous computed tomography (CT exams. Univariate and extreme scenarios sensitivity analyses were conducted to evaluate the influence from sources of uncertainties in the parameters used.RESULTS The incorporation of PET-CT in SUS would imply the need for additional resources of 158.1 BRL (98.2 USD million for the restricted offer and 202.7 BRL (125.9 USD million for the inclusive offer in five years, with a difference of 44.6 BRL (27.7 USD million between the two offer strategies within that period. In absolute terms, the total budget impact from its incorporation in SUS, in five years, would be 555 BRL (345 USD and 600 BRL (372.8 USD million, respectively. The costs from the PET-CT procedure were the most influential parameter in the results. In the most optimistic scenario, the additional budget impact would be reduced to 86.9 BRL (54 USD and 103.8 BRL (64.5 USD million, considering PET-CT for negative CT and PET-CT for all, respectively.CONCLUSIONS The incorporation of PET in the clinical staging of non-small cell lung cancer seems to be financially feasible considering the high budget of the Brazilian Ministry of Health. The potential reduction in the number of unnecessary surgeries may cause the available resources to be more efficiently allocated.

  11. [18F]2-fluoro-2-deoxyglucose positron emission tomography/computed tomography in predicting radiation pneumonitis

    Institute of Scientific and Technical Information of China (English)

    SONG Hao; YU Jin-ming; Feng-ming Kong; LU Jie; BAI Tong; MA Li; FU Zheng

    2009-01-01

    Background Prevention is presently the only available method to limit radiation-induced lung morbidity. A good predictor is the key point of prevention. This study aimed to investigate if [18F]2-fluoro-2-deoxyglucose (FDG) uptake changes in the lung after radiotherapy could be used as a new predictor for acute radiation pneumonitis (RP). Methods Forty-one patients with lung cancer underwent FDG positron emission tomography/computed tomography (FDG-PET/CT) imaging before and after radiotherapy. The mean standardized uptake value (SUV) was measured for the isodose regions of 0-9 Gy, 10-19 Gy, 20-29 Gy, 30-39 Gy, 40-49 Gy. The mean SUV of these regions after radiotherapy was compared with baseline. The mean SUV in patients who developed RP was also compared with that in those who did not. The statistical difference was determined by matched pair t test. The Radiation Therapy Oncology Group (RTOG)criteria were used for diagnosis and grading of RP.Results With a median follow-up of 12 months, 11 (26.8%) of the 41 patients developed grade 2 and above acute RP.The mean SUV of regions (10-19 Gy, 20-29 Gy, 30-39 Gy, 40-49 Gy) increased after radiation therapy in all 41 patients.The mean SUVs after radiation therapy were 0.54, 0.68, 1.31, 1.74 and 2.27 for 0-9 Gy, 10-19 Gy, 20-29 Gy, 30-39 Gy and 40-49 Gy, respectively. Before the radiation therapy, the mean SUV in each region was 0.53, 0.52, 0.52, 0.53 and 0.54, respectively. These patients had significantly higher FDG activities in regions receiving 10 Gy or more (P <0.001).Compared with their counterparts, the elevation of SUV was significantly greater in those patients who developed acute RP subsequently.Conclusion The mean SUV of the lung tissue may be a useful predictor for the acute RR FDG-PET/CT may play a new role in the study of the radiation damage of the lung.

  12. High-resolution PET [Positron Emission Tomography] for Medical Science Studies

    Science.gov (United States)

    Budinger, T. F.; Derenzo, S. E.; Huesman, R. H.; Jagust, W. J.; Valk, P. E.

    1989-09-01

    One of the unexpected fruits of basic physics research and the computer revolution is the noninvasive imaging power available to today's physician. Technologies that were strictly the province of research scientists only a decade or two ago now serve as the foundations for such standard diagnostic tools as x-ray computer tomography (CT), magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), ultrasound, single photon emission computed tomography (SPECT), and positron emission tomography (PET). Furthermore, prompted by the needs of both the practicing physician and the clinical researcher, efforts to improve these technologies continue. This booklet endeavors to describe the advantages of achieving high resolution in PET imaging.

  13. Recurrent proliferating trichilemmal tumor with malignant change on the f-18 fluorodeoxyglucose position emission tomography/computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Eun Ha; Kim, Eun Ha; Kim, Young Jun; Yoo, Seol Bong; Nam, Kyung Hwa [Presbyterian Medical Center, Seonam University College of Medicine, Jeonju (Korea, Republic of)

    2016-06-15

    F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography scan has been used for the diagnosis, assessment of treatment response, and follow-up of various neoplasms. Proliferating trichilemmal cyst or tumor (PTT) is a rare neoplasm, originated from the outer root sheath of a hair follicle. Because this tumor has unpredictable biological and clinical behavior, the long-term clinical follow-up is necessary to detect metastasis or recurrence. We reported a case of recurrent malignant PTT on scalp that showed increased FDG uptake.

  14. Role of F18 fluorodeoxyglucose positron-emission tomography/computed tomography in the management of Askin's tumor.

    Science.gov (United States)

    Santhosh, Sampath; Kashyap, Raghava; Bhattacharya, Anish; Kumar Jindal, Surinder; Rai Mittal, Bhagwant

    2013-07-01

    A primitive neuroectodermal tumor (PNET) of the thoraco-abdominal region is one of a group of small round cell tumors usually found in children and young adults, originally described by Askin et al. Most cases arise in the soft-tissues of the thorax, but may rarely occur within the lung with the symptoms of chest wall pain, pleural effusion and dyspnea. The authors present two cases demonstrating the utility of F18 fluorodeoxyglucose positron-emission tomography/computed tomography in the staging and prognosis of PNET of the chest wall.

  15. Comparison of diffuse optical tomography of human breast with whole-body and breast-only positron emission tomography.

    Science.gov (United States)

    Konecky, Soren D; Choe, Regine; Corlu, Alper; Lee, Kijoon; Wiener, Rony; Srinivas, Shyam M; Saffer, Janet R; Freifelder, Richard; Karp, Joel S; Hajjioui, Nassim; Azar, Fred; Yodh, Arjun G

    2008-02-01

    We acquire and compare three-dimensional tomographic breast images of three females with suspicious masses using diffuse optical tomography (DOT) and positron emission tomography (PET). Co-registration of DOT and PET images was facilitated by a mutual information maximization algorithm. We also compared DOT and whole-body PET images of 14 patients with breast abnormalities. Positive correlations were found between total hemoglobin concentration and tissue scattering measured by DOT, and fluorodeoxyglucose (18F-FDG) uptake. In light of these observations, we suggest potential benefits of combining both PET and DOT for characterization of breast lesions.

  16. Positron emission tomography/computed tomography and biomarkers for early treatment response evaluation in metastatic colon cancer

    DEFF Research Database (Denmark)

    Engelmann, Bodil E.; Loft, Annika; Kjær, Andreas;

    2014-01-01

    BACKGROUND: Treatment options for metastatic colon cancer (mCC) are widening. We prospectively evaluated serial 2-deoxy-2-[18F]fluoro-d-glucose positron-emission tomography/computed tomography (PET/CT) and measurements of tissue inhibitor of metalloproteinases-1 (TIMP-1), carcinoembryonic antigen...... evaluated by PET/CT before treatment, after one and four treatment series. Morphological and metabolic response was independently assessed according to Response Evaluation Criteria in Solid Tumors and European Organization for Research and Treatment of Cancer PET criteria. Plasma TIMP-1, plasma u...

  17. The accuracy of positron emission tomography in the detection of posttransplant lymphoproliferative disorder.

    Science.gov (United States)

    Dierickx, Daan; Tousseyn, Thomas; Requilé, Annelies; Verscuren, Raf; Sagaert, Xavier; Morscio, Julie; Wlodarska, Iwona; Herreman, An; Kuypers, Dirk; Van Cleemput, Johan; Nevens, Frederik; Dupont, Lieven; Uyttebroeck, Anne; Pirenne, Jacques; De Wolf-Peeters, Christiane; Verhoef, Gregor; Brepoels, Lieselot; Gheysens, Olivier

    2013-05-01

    We investigated sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 18F-fluorodeoxyglucose-positron emission tomography in 170 cases with suspected or biopsy-proven posttransplant lymphoproliferative disorder. All solid organ and hematopoietic stem cell transplant recipients who underwent an 18F-fluorodeoxyglucose-positron emission tomography scan between 2003 and 2010 in our center for the indication posttransplant lymphoproliferative disorder, were retrospectively reviewed and results were compared with tissue biopsy whenever possible. One hundred and seventy positron emission tomography scans in 150 patients were eligible for evaluation. In 45 cases, the patient had a biopsy-confirmed posttransplant lymphoproliferative disorder before positron emission tomography scanning and positron emission tomography was performed for staging purposes. In the remaining 125 cases, positron emission tomography was performed to differentiate between posttransplant lymphoproliferative disorder and other diseases. 18F-fluorodeoxyglucose-uptake was quantitatively expressed by calculation of maximum and mean standardized uptake value in the most intense lesion or, in the absence of attenuation corrected positron emission tomography scans, by comparing uptake in target lesion to liver and mediastinal uptake. We found an overall sensitivity of 89%, specificity of 89%, positive predictive value of 91% and negative predictive value of 87% for posttransplant lymphoproliferative disorder detection by 18F-fluorodeoxyglucose-positron emission tomography. In a subanalysis of the 125 scans performed for differentiating posttransplant lymphoproliferative disorder from other diseases, sensitivity, specificity, positive predictive value and negative predictive value were 90%, 89%, 85% and 93%, respectively. 18F-fluorodeoxyglucose-uptake in posttransplant lymphoproliferative disorder was generally high with a median mean and maximum standardized uptake

  18. Attenuation correction for X-ray emission computed tomography of laser-produced plasma

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yen-Wei; Nakao, Zensho [Ryukyus Univ., Nishihara, Okinawa (Japan). Faculty of Engineering; Tamura, Shinichi

    1996-08-01

    An attenuation correction method was proposed for laser-produced plasma emission computed tomography (ECT), which is based on a relation of the attenuation coefficient and the emission coefficient in plasma. Simulation results show that the reconstructed images are dramatically improved in comparison to the reconstructions without attenuation correction. (J.P.N.)

  19. Practical implementation of tetrahedral mesh reconstruction in emission tomography

    Science.gov (United States)

    Boutchko, R.; Sitek, A.; Gullberg, G. T.

    2013-05-01

    This paper presents a practical implementation of image reconstruction on tetrahedral meshes optimized for emission computed tomography with parallel beam geometry. Tetrahedral mesh built on a point cloud is a convenient image representation method, intrinsically three-dimensional and with a multi-level resolution property. Image intensities are defined at the mesh nodes and linearly interpolated inside each tetrahedron. For the given mesh geometry, the intensities can be computed directly from tomographic projections using iterative reconstruction algorithms with a system matrix calculated using an exact analytical formula. The mesh geometry is optimized for a specific patient using a two stage process. First, a noisy image is reconstructed on a finely-spaced uniform cloud. Then, the geometry of the representation is adaptively transformed through boundary-preserving node motion and elimination. Nodes are removed in constant intensity regions, merged along the boundaries, and moved in the direction of the mean local intensity gradient in order to provide higher node density in the boundary regions. Attenuation correction and detector geometric response are included in the system matrix. Once the mesh geometry is optimized, it is used to generate the final system matrix for ML-EM reconstruction of node intensities and for visualization of the reconstructed images. In dynamic PET or SPECT imaging, the system matrix generation procedure is performed using a quasi-static sinogram, generated by summing projection data from multiple time frames. This system matrix is then used to reconstruct the individual time frame projections. Performance of the new method is evaluated by reconstructing simulated projections of the NCAT phantom and the method is then applied to dynamic SPECT phantom and patient studies and to a dynamic microPET rat study. Tetrahedral mesh-based images are compared to the standard voxel-based reconstruction for both high and low signal-to-noise ratio

  20. Computed tomography and (18)F-fluorodeoxyglucose positron emission tomography/computed tomography findings in adrenal candidiasis and histoplasmosis: two cases.

    Science.gov (United States)

    Altinmakas, Emre; Guo, Ming; Kundu, Uma R; Habra, Mouhammed Amir; Ng, Chaan

    2015-01-01

    We report the contrast-enhanced computed tomography (CT) and (18)F-fluorodeoxyglucose positron emission tomography findings in adrenal histoplasmosis and candidiasis. Both demonstrated bilateral hypermetabolic heterogeneous adrenal masses with limited wash-out on delayed CT. Adrenal candidiasis has not been previously reported, nor have the CT wash-out findings in either infection. The adrenal imaging findings are indistinguishable from malignancy, which is more common; but in this setting, physicians should be alert to the differential diagnosis of fungal infections, since it can be equally deadly.

  1. Fabrication of polycrystalline scintillators for the positron emission tomography (PET); Herstellung polykristalliner Szintillatoren fuer die Positronen-Emissions-Tomographie (PET)

    Energy Technology Data Exchange (ETDEWEB)

    Karim, Kamran Said

    2010-07-01

    Transparent ceramics are becoming more and more important for two new types of applications. On the one hand in cases where high mechanical and thermal demands in combination with optical properties are required, on the other hand where the optical properties of transparent materials like glass are not sufficient e.g. in positron-emission-tomography (PET) diagnostics. Most state of the art PET-scanners are using high-priced single crystals as scintillator material. The technological challenge is to replace single crystal by cost-efficient transparent ceramics. Producing transparent ceramics is ordered in synthesis of the powders and in manufacturing of these into transparent ceramics. The aim of this work was to synthesize single phase yttrium-alumina-and Luthetiumalumina-garnet (YAG, LuAG) powders partially doped with neodymium or praseodymium by four different synthesis routes (Pechini-synthesis, sol-gel-route, coprecipitation and solid state reactions). Additionally industrial LuAG and LuPO{sub 4} powders were characterized and manufactured. The powders were processed as submicron- and nanopowders. The compaction of nanopowder greenbodies sintered at high temperatures leads to a ''cross-over'' between both manufacturing route. Newly produced single-phase powders were homogenized with additions of sintering additives like tetraethyl orthosilicate (TEOS) and binders like polyvinyl alcohol (PVA). Moulding the powders were carried out by uniaxial pressing, cold isostatic pressing and in individual cases also by slip casting. The achieved green densities were in a range of 25-42 %. Examination of calcination behaviour leads to a calcination temperature of 1000 C with 2 hours dwell time in air atmosphere. Only solid state reactions resulted into transparent YAG, YAG:Pr, LuAG, LuAG:Pr ceramics. Solid state reactions of nanopowders resulted in heterogeneously transparent samples. Ceramics made by powders of other synthetic routes gave nontransparent

  2. Molecular Imaging of Transporters with Positron Emission Tomography

    Science.gov (United States)

    Antoni, Gunnar; Sörensen, Jens; Hall, Håkan

    Positron emission tomography (PET) visualization of brain components in vivo is a rapidly growing field. Molecular imaging with PET is also increasingly used in drug development, especially for the determination of drug receptor interaction for CNS-active drugs. This gives the opportunity to relate clinical efficacy to per cent receptor occupancy of a drug on a certain targeted receptor and to relate drug pharmacokinetics in plasma to interaction with target protein. In the present review we will focus on the study of transporters, such as the monoamine transporters, the P-glycoprotein (Pgp) transporter, the vesicular monoamine transporter type 2, and the glucose transporter using PET radioligands. Neurotransmitter transporters are presynaptically located and in vivo imaging using PET can therefore be used for the determination of the density of afferent neurons. Several promising PET ligands for the noradrenaline transporter (NET) have been labeled and evaluated in vivo including in man, but a really useful PET ligand for NET still remains to be identified. The most promising tracer to date is (S,S)-[18F]FMeNER-D2. The in vivo visualization of the dopamine transporter (DAT) may give clues in the evaluation of conditions related to dopamine, such as Parkinson's disease and drug abuse. The first PET radioligands based on cocaine were not selective, but more recently several selective tracers such as [11C]PE2I have been characterized and shown to be suitable as PET radioligands. Although there are a large number of serotonin transporter inhibitors used today as SSRIs, it was not until very recently, when [11C]McN5652 was synthesized, that this transporter was studied using PET. New candidates as PET radioligands for the SERT have subsequently been developed and [11C]DASB and [11C]MADAM and their analogues are today the most promising ligands. The existing radioligands for Pgp transporters seem to be suitable tools for the study of both peripheral and central drug

  3. Single-Photon Emission Computerized Tomography (SPECT in Neuropsychiatry: A Review

    Directory of Open Access Journals (Sweden)

    B. K. Puri

    1992-01-01

    Full Text Available Cranial single-photon emission computerized tomography (SPECT or SPET can now give regional cerebral blood flow images with a resolution approaching that of positron emission tomography (PET. In this paper, the use of high resolution SPECT neuroimaging in neuropsychiatric disorders, including Alzheimer's disease, multi-infarct dementia, Pick's disease, progressive supranuclear palsy, Korsakoff's psychosis, Creutzfeld-Jakob disease, Parkinson's disease, Huntington's disease, schizophrenia, mood disorders, obsessive–compulsive disorder, HIV infection and AIDS is reviewed. Finally, further potential research and clinical uses, based on ligand studies, are outlined.

  4. Respiratory motion in positron emission tomography for oncology applications: Problems and solutions

    Energy Technology Data Exchange (ETDEWEB)

    Visvikis, D. [INSERM U650, LaTIM, University Hospital Medical School, F-29609, Brest (France)]. E-mail: Visvikis.Dimitris@univ-brest.fr; Lamare, F. [INSERM U650, LaTIM, University Hospital Medical School, F-29609, Brest (France); Bruyant, P. [INSERM U650, LaTIM, University Hospital Medical School, F-29609, Brest (France); Boussion, N. [INSERM U650, LaTIM, University Hospital Medical School, F-29609, Brest (France); Cheze Le Rest, C. [INSERM U650, LaTIM, University Hospital Medical School, F-29609, Brest (France)

    2006-12-20

    The effect of physiological motion in emission tomography is a reduction in overall image contrast and loss of sensitivity. In particular, respiratory motion affects imaging in the thoracic and the upper abdomen area, leading to a reduction in lesion detection as a result of the associated blurring. Furthermore, respiratory motion leads to a compromise in quantitative accuracy in terms of functional volume determination and activity concentration recovery for oncology imaging. This paper presents a review of the current state of the art in the implementation of respiratory motion compensation techniques in positron emission tomography (PET) imaging for oncology applications.

  5. Position emission tomography with or without computed tomography in the primary staging of Hodgkin's lymphoma

    DEFF Research Database (Denmark)

    Hutchings, Martin; Jakobsen, Annika Loft; Hansen, Mads;

    2006-01-01

    In order to receive the most appropriate therapy, patients with Hodgkin's lymphoma (HL) must be accurately stratified into different prognostic staging groups. Computed tomography (CT) plays a pivotal role in the conventional staging. The aim of the present study was to investigate the value...

  6. Contrast-enhanced fluorodeoxyglucose positron emission tomography/computed tomography in solid pseudopapillary neoplasm of the pancreas.

    Science.gov (United States)

    Santhosh, Sampath; Lakshmanan, Ramesh Kumar; Sonik, Bhavay; Padmavathy, Rajagopalan; Gunaseelan, Rajamani Emmanuel

    2016-01-01

    Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare pancreatic tumor with low malignant potential. It occurs characteristically more often in young women. Radiological and pathological studies have revealed that the tumor is quite different from other pancreatic tumors. Limited information is available in the literature reporting their accumulation of fluorine-(18) fluorodeoxyglucose ((18)F-FDG) in positron emission tomography/computed tomography (PET/CT). Here, we report a case of pancreatic SPN imaged with contrast-enhanced FDG PET/CT. A percutaneous fine needle aspiration from the metabolically active lesion revealed SPN, and it was confirmed with histopathological results. Recurrence or metastasis was not found after 7 months of follow-up.

  7. [18F]Fluorodeoxyglucose (FDG)-Positron Emission Tomography (PET)/Computed Tomography (CT) in Suspected Recurrent Breast Cancer

    DEFF Research Database (Denmark)

    Hildebrandt, Malene Grubbe; Gerke, Oke; Baun, Christina;

    2016-01-01

    PURPOSE: To prospectively investigate the diagnostic accuracy of [(18)F]fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) with dual-time-point imaging, contrast-enhanced CT (ceCT), and bone scintigraphy (BS) in patients with suspected breast cancer recurrence....... PATIENTS AND METHODS: One hundred women with suspected recurrence of breast cancer underwent 1-hour and 3-hour FDG-PET/CT, ceCT, and BS within approximately 10 days. The study was powered to estimate the precision of the individual imaging tests. Images were visually interpreted using a four...... the receiver operating curve and higher sensitivity, specificity, and superior likelihood ratios. CONCLUSION: FDG-PET/CT was accurate in diagnosing recurrence in breast cancer patients. It allowed for distant recurrence to be correctly ruled out and resulted in only a small number of false-positive cases...

  8. Are we ready for positron emission tomography/computed tomography-based target volume definition in lymphoma radiation therapy?

    Science.gov (United States)

    Yeoh, Kheng-Wei; Mikhaeel, N George

    2013-01-01

    Fluorine-18 fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) has become indispensable for the clinical management of lymphomas. With consistent evidence that it is more accurate than anatomic imaging in the staging and response assessment of many lymphoma subtypes, its utility continues to increase. There have therefore been efforts to incorporate PET/CT data into radiation therapy decision making and in the planning process. Further, there have also been studies investigating target volume definition for radiation therapy using PET/CT data. This article will critically review the literature and ongoing studies on the above topics, examining the value and methods of adding PET/CT data to the radiation therapy treatment algorithm. We will also discuss the various challenges and the areas where more evidence is required.

  9. 18F-fluorodeoxyglucose-positron emission tomography/computed tomography after one cycle of chemotherapy in patients with diffuse large B-cell lymphoma

    DEFF Research Database (Denmark)

    Mylam, Karen Juul; Kostakoglu, Lale; Hutchings, Martin;

    2015-01-01

    We evaluated the predictive value of interim positon emission tomography (I-PET) after one course of chemoimmunotherapy in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL). One hundred and twelve patients with DLBCL were enrolled. All patients had PET/computed tomography (CT) s...

  10. 18F-fluoro-deoxy-glucose-positron emission tomography/computed tomography in diagnosis of head and neck squamous cell carcinoma

    DEFF Research Database (Denmark)

    Rohde, Max; Dyrvig, Anne-Kirstine; Johansen, Jørgen;

    2014-01-01

    18F-fluoro-deoxy-glucose-positron emission tomography/computed tomography-scan (PET/CT) is used increasingly for detection of cancer. Precise diagnostic assessment of tumour extension in head and neck squamous cell carcinoma (HNSCC) is of critical importance for ensuring that patients receive...

  11. Clinical Relevance of Incidental Prostatic Lesions on FDG-Positron Emission Tomography/Computerized Tomography-Should Patients Receive Further Evaluation?

    NARCIS (Netherlands)

    Reesink, Daan J; Fransen van de Putte, Elisabeth E; Vegt, Erik; De Jong, Jeroen; van Werkhoven, Erik; Mertens, Laura S; Bex, Axel; van der Poel, Henk G; van Rhijn, Bas W G; Horenblas, Simon; Meijer, Richard P

    2016-01-01

    PURPOSE: FDG ((18)F-fluoro-2-deoxy-D-glucose)-PET/CT (positron emission tomography)/(computerized tomography) is a widely used diagnostic tool for whole body imaging. Incidental prostatic uptake is often found on FDG-PET/CT. The objective of this study was to determine the clinical relevance of inci

  12. FDG-positron emission tomography/computed tomography and standardized uptake value in the primary diagnosis and staging of hilar cholangiocarcinoma

    NARCIS (Netherlands)

    A.T. Ruys; R.J. Bennink; H.L. van Westreenen; M.R. Engelbrecht; O.R. Busch; D.J. Gouma; T.M. van Gulik

    2011-01-01

    Background: The diagnosis and staging of hilar cholangiocarcinoma (HCCA) remain challenging despite recent advances in imaging. Little is known about the use of positron emission tomography/computed tomography (PET/CT) in HCCA. Objectives: This study aimed to evaluate the additional value of FDG-PET

  13. Right parietal stroke with Gerstmann's syndrome. Appearance on computed tomography, magnetic resonance imaging, and single-photon emission computed tomography.

    Science.gov (United States)

    Moore, M R; Saver, J L; Johnson, K A; Romero, J A

    1991-04-01

    We examined a patient who exhibited Gerstmann's syndrome (left-right disorientation, finger agnosia, dyscalculia, and dysgraphia) in association with a perioperative stroke in the right parietal lobe. This is the first description of the Gerstmann tetrad occurring in the setting of discrete right hemisphere pathologic findings. A well-localized vascular lesion was demonstrated by computed tomography, magnetic resonance imaging, and single-photon emission computed tomographic studies. The patient had clinical evidence of reversed functional cerebral dominance and radiologic evidence of reversed anatomic cerebral asymmetries.

  14. High-resolution PET (positron emission tomography) for medical science studies

    Energy Technology Data Exchange (ETDEWEB)

    Budinger, T.F.; Derenzo, S.E.; Huesman, R.H.; Jagust, W.J.; Valk, P.E. (Lawrence Berkeley Lab., CA (USA))

    1989-09-01

    One of the unexpected fruits of basic physics research and the computer revolution is the noninvasive imaging power available to today's physician. Technologies that were strictly the province of research scientists only a decade or two ago now serve as the foundations for such standard diagnostic tools as x-ray computer tomography (CT), magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), ultrasound, single photon emission computed tomography (SPECT), and positron emission tomography (PET). Furthermore, prompted by the needs of both the practicing physician and the clinical researcher, efforts to improve these technologies continue. This booklet endeavors to describe the advantages of achieving high resolution in PET imaging. 6 refs., 21 figs.

  15. Plastic scintillators for positron emission tomography obtained by the bulk polymerization method

    CERN Document Server

    Kapłon, Łukasz; Molenda, Marcin; Moskal, Paweł; Wieczorek, Anna; Bednarski, Tomasz; Białas, Piotr; Czerwiński, Eryk; Korcyl, Grzegorz; Kowal, Jakub; Kowalski, Paweł; Kozik, Tomasz; Krzemień, Wojciech; Niedźwiecki, Szymon; Pałka, Marek; Pawlik, Monika; Raczyński, Lech; Rudy, Zbigniew; Salabura, Piotr; Gupta-Sharma, Neha; Silarski, Michał; Słomski, Artur; Smyrski, Jerzy; Strzelecki, Adam; Wiślicki, Wojciech; Zieliński, Marcin; Zoń, Natalia

    2015-01-01

    This paper describes three methods regarding the production of plastic scintillators. One method appears to be suitable for the manufacturing of plastic scintillator, revealing properties which fulfill the requirements of novel positron emission tomography scanners based on plastic scintillators. The key parameters of the manufacturing process are determined and discussed.

  16. 77 FR 8262 - Draft Guidance on Investigational New Drug Applications for Positron Emission Tomography Drugs...

    Science.gov (United States)

    2012-02-14

    ... HUMAN SERVICES Food and Drug Administration Draft Guidance on Investigational New Drug Applications for Positron Emission Tomography Drugs; Availability AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug Administration (FDA) is announcing the availability of a draft...

  17. Diagnosis of heterotopic bone marrow in the mediastinum using /sup 52/Fe and positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Borgies, P. (Cliniques Universitaires Saint-Luc, Brussels (Belgium). Dept. of Hematology; Cliniques Universitaires Saint-Luc, Brussels (Belgium). Dept. of Nuclear Medicine); Ferrant, A. (Louvain Univ., Louvain-la-Neuve (Belgium). Lab. of Positron Emission Tomography); Leners, N.; Michaux, J.L.; Bol, A.; Michel, C.; Cogneau, M.; Sokal, G.

    1989-11-01

    A patient with hereditary spherocytosis was admitted with mediastinal masses on the chest X-ray. /sup 52/Fe and positron emission tomography (PET) showed uptake of /sup 52/Fe in the masses and established the diagnosis of thoracic extra medullary hematopoiesis. (orig.).

  18. Regional cerebral blood flow assessed by 133Xe inhalation and emission tomography

    DEFF Research Database (Denmark)

    Shirahata, N; Henriksen, L; Vorstrup, S

    1985-01-01

    Regional cerebral blood flow (rCBF) in the cerebral hemispheres and the cerebellum was measured by single photon emission computed tomography with inhalation of 133Xe in 39 normal volunteers at test. The goal of this study was to assess the normal flow pattern and its variations. Five parallel...

  19. Measuring endogenous 5-HT release by emission tomography: promises and pitfalls

    DEFF Research Database (Denmark)

    Paterson, Louise M; Tyacke, Robin J; Nutt, David J;

    2010-01-01

    emission tomography, but has not yet been adequately extended to other neurotransmitter systems. This review focuses on how the technique has been applied to the study of the 5-hydroxytryptamine (5-HT) system. The principles behind visualising fluctuations in neurotransmitters are introduced...

  20. Cobalt-55 positron emission tomography of ipsilateral thalamic and crossed cerebellar hypometabolism after supratentorial ischaemic stroke

    NARCIS (Netherlands)

    De Reuck, J; Stevens, H; Jansen, H; Keppens, J; Strijckmans, K; Goethals, P; Lemahieu, [No Value; Santens, P; Korf, J

    1999-01-01

    Cobalt-55 (Co-55) is a positron emission tomography (PET) tracer used to demonstrate brain damage, possibly associated to calcium-mediated processes. The degree of Co-55 accumulation correlates with the severity of ischaemia in stroke patients. It is still a matter of debate whether ipsilateral thal

  1. Positron emission tomography in presurgical diagnosis of partial epilepsies. Praeoperative Lokalisationsdiagnostik bei fokaler Epilepsie durch PET

    Energy Technology Data Exchange (ETDEWEB)

    Hajek, M.; Leenders, K.L. (Universitaetsspital Zurich (Switzerland). Neurologische Klinik Paul Scherrer Institut, Villigen (Switzerland)); Wieser, H.G. (Universitaetsspital Zurich (Switzerland). Neurologische Klinik)

    1992-06-01

    We present results of studies in which positron emission tomography was applied to the presurgical evaluation of epileptics. Emphasis is placed on results of PET studies with various tracers in partial epilepsies and on the use of PET in age-related epileptic syndromes in children. (orig.).

  2. A 5D computational phantom for pharmacokinetic simulation studies in dynamic emission tomography

    NARCIS (Netherlands)

    Kotasidis, Fotis A.; Tsoumpas, Charalampos; Polycarpou, Irene; Zaidi, Habib

    2014-01-01

    Introduction: Dynamic image acquisition protocols are increasingly used in emission tomography for drug development and clinical research. As such, there is a need for computational phantoms to accurately describe both the spatial and temporal distribution of radiotracers, also accounting for period

  3. Positron emission tomography (PET) methodology for small animals and its application in radiopharmaceutical preclinical investigation

    Energy Technology Data Exchange (ETDEWEB)

    Hume, Susan P.; Jones, Terry

    1998-11-01

    The use and usefulness of positron emission tomography (PET) to quantify the specific and selective in vivo binding of radioligands in small laboratory animals is briefly reviewed up to the end of 1996. Emphasis is placed on practical experience with a dedicated, small diameter, tomograph (built in collaboration with CTI, Knoxville, TN), implementing conventional PET methodology.

  4. Activity-based costing evaluation of a [F-18]-fludeoxyglucose positron emission tomography study

    NARCIS (Netherlands)

    Krug, Bruno; Van Zanten, Annie; Pirson, Anne-Sophie; Crott, Ralph; Vander Borght, Thierry

    2009-01-01

    Objective: The aim of the study is to use the activity-based costing approach to give a better insight in the actual cost structure of a positron emission tomography procedure (FDG-PET) by defining the constituting components and by simulating the impact of possible resource or practice changes. Met

  5. Detection of unknown primary head and neck tumors by positron emission tomography

    NARCIS (Netherlands)

    Braams, JW; Pruim, J; Kole, AC; Nikkels, PGJ; Vaalburg, W; Vermey, A; Roodenburg, JLN

    1997-01-01

    The purpose of this study was to investigate the potential of using positron emission tomography (PET) with F-18-labeled fluoro-2-deoxy-D-glucose (FDG) to detect unknown primary tumors of cervical metastases. Thirteen patients with various histologic types of cervical metastases of unknown primary o

  6. A method for calculating regional cerebral blood flow from emission computed tomography of inert gas concentrations

    DEFF Research Database (Denmark)

    Celsis, P; Goldman, T; Henriksen, L;

    1981-01-01

    of four 1 min pictures and using a fixed value for the brain:blood partition coefficient, lambda. The method is essentially based on the bolus distribution principle, and it allows the estimation of blood flow in ischemic areas. Application to positron emission tomography is discussed....

  7. Increased fluoro-deoxy-D-glucose uptake on positron emission tomography-computed tomography postbronchoalveolar lavage: a potential cause of radiologic misinterpretation.

    LENUS (Irish Health Repository)

    Leong, Sum

    2011-08-01

    Cytologic analysis of bronchoalveolar lavage (BAL) fluid is used for lung cancer diagnosis. We describe a patient with a history of rectal carcinoma who presented with a new lung mass. BAL was performed, with positron emission tomography-computed tomography the following day. There was mildly increased fluoro-deoxy-D-glucose uptake in areas of the lung parenchyma with new ground-glass opacification. This created ambiguity in staging, clarified 2 weeks later by a computed tomography showing complete resolution of the ground-glass opacity. Clinicians should be aware that BAL may cause increased pulmonary fluoro-deoxy-D-glucose uptake, making accurate radiologic interpretation problematic. We suggest that to optimize positron emission tomography-computed tomography, studies should not be performed within 24 hours of BAL.

  8. An index of pulmonary edema measured with emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Ahluwalia, B.D.; Brownell, G.L.; Hales, C.A.; Kazemi, H.

    1981-10-01

    Positron camera and short-lived biological isotopes are used to obtain transverse sections of lung volume, blood volume, and total lung water of dog lungs to assess the degree of pulmonary edema in normal and edematous dogs. At equilibration with specific isotope, 30 equally spaced angular profiles of the distribution are collected to obtain transverse section images. Emission computed number is obtained in the lung and heart areas for the images obtained with an intravascular marker (11CO) and intra- and extravascular marker (C15O2). The emission computed number ratio of lung to heart for C15O2 images is an index that is related to degree of edema. Emission computed number related to extravascular water can be obtained from normalized (C15O2--11CO) scintigrams. The technique is noninvasive.

  9. Position emission tomography with or without computed tomography in the primary staging of Hodgkin's lymphoma

    DEFF Research Database (Denmark)

    Hutchings, Martin; Loft, Annika; Hansen, Mads

    2006-01-01

    BACKGROUND AND OBJECTIVES: In order to receive the most appropriate therapy, patients with Hodgkin's lymphoma (HL) must be accurately stratified into different prognostic staging groups. Computed tomography (CT) plays a pivotal role in the conventional staging. The aim of the present study...... standard limits the reliability of accuracy calculations. RESULTS: FDG-PET would have upstaged 19% of patients and downstaged 5% of patients, leading to a different treatment in 9% of patients. For FDG-PET/CT, the corresponding figures are 17%, 5%, and 7%. In nodal regions, the sensitivity of FDG...

  10. Positron Emission Tomography: Current Challenges and Opportunities for Technological Advances in Clinical and Preclinical Imaging Systems.

    Science.gov (United States)

    Vaquero, Juan José; Kinahan, Paul

    2015-01-01

    Positron emission tomography (PET) imaging is based on detecting two time-coincident high-energy photons from the emission of a positron-emitting radioisotope. The physics of the emission, and the detection of the coincident photons, give PET imaging unique capabilities for both very high sensitivity and accurate estimation of the in vivo concentration of the radiotracer. PET imaging has been widely adopted as an important clinical modality for oncological, cardiovascular, and neurological applications. PET imaging has also become an important tool in preclinical studies, particularly for investigating murine models of disease and other small-animal models. However, there are several challenges to using PET imaging systems. These include the fundamental trade-offs between resolution and noise, the quantitative accuracy of the measurements, and integration with X-ray computed tomography and magnetic resonance imaging. In this article, we review how researchers and industry are addressing these challenges.

  11. The positrons emission tomography in cardiology on expecting for the rubidium 82; La tomographie par emission de positons en cardiologie en attendant le rubidium-82

    Energy Technology Data Exchange (ETDEWEB)

    Agostini, D. [Societe Francaise de Cardiologie Nucleaire et IRM, 75 - Paris (France)

    2005-11-15

    The positron emission tomography in cardiology has an important place in France. A new tracer, the rubidium 82 can be used for the detection of myocardium ischemia among the patients where the SPECT was ineffective or not very useful, it will be necessary to propose a permit to market the tracer in the two next years.Recently, the Food drug administration in Usa has allowed the repayment of the rubidium 82 for the myocardium detection as normal or abnormal in the post myocardium infarction. (N.C.)

  12. Degenerative dementia: nosological aspects and results of single photon emission computed tomography; Les demences degeneratives: aspects nosologiques et resultats de la tomographie d'emission monophotonique

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, B.; Habert, M.O. [Hopital Pitie-Salpetriere, 75 - Paris (France)

    1999-12-01

    Ten years ago, the diagnosis discussion of a dementia case for the old patient was limited to two pathologies: the Alzheimer illness and the Pick illness. During these last years, the frame of these primary degenerative dementia has fallen into pieces. The different diseases and the results got with single photon emission computed tomography are discussed. for example: fronto-temporal dementia, primary progressive aphasia, progressive apraxia, visio-spatial dysfunction, dementia at Lewy's bodies, or cortico-basal degeneration. (N.C.)

  13. Evaluation of focal thyroid lesions incidentally detected in fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography images

    Directory of Open Access Journals (Sweden)

    O Yaylali

    2014-01-01

    Full Text Available Background and Purpose: Increased uptake in the thyroid gland (TG is often identified as an incidental finding on the whole body fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT in non-thyroid cancer patients. Currently, there is no consensus on the appropriate approach for the management of these cases. Thyroid ultrasound, scintigraphy and fine-needle aspiration biopsy (FNAB are suggested to exclude malignant thyroid lesions. Our aim is to determine the importance of increased F-18-FDG uptake in the TG on positron emission tomography/computed tomography (PET/CT scans in patients who are being screened for various forms of non-thyroid cancer. Materials and Methods: We evaluated 2000 cases undergoing whole body PET/CT scanning between April 2011 and October 2012. The age, sex, type of primary cancer, maximum standardized uptake value (SUV max , size of the thyroid nodules and cervical lymph nodes (CLNs on 18 F-FDG PET/CT images and if available, the biopsy results were evaluated. Results: In total, 57 patients (23 men, 34 women, mean age ± standard deviation (SD, 60.89 ± 14 years showed an increased fluorine-18-fluorodeoxyglucose ( 18 F-FDG uptake by the TG (average SUV max : 4.07 ± 3.7. The CLNs were detected in 19/57 patients (33%. Only 20 cases (35% received FNAB. The final histopathological diagnosis was papillary thyroid carcinoma in seven patients (mean SUV max ± SD: 6.0 ± 5.43 and benign thyroid disease in seven patients (mean SUV max ± SD: 2.36 ± 0.63. The FNAB results were undetermined for six patients. Conclusion: Focal high 18 F-FDG uptake in the TG may be associated with an increased risk of malignancy, but the clinical significance is unclear. More data are needed to elucidate the role of the SUV in the differentiation of benign and malign thyroid lesions. If a focal increase in 18 F-FDG uptake in the TG on PET/CT is present, a prompt histopathological evaluation should be

  14. Recent innovations in the detection systems of Positron Emission Tomography; Innovations technologiques recentes en detection pour la Tomographie par Emission de Positons

    Energy Technology Data Exchange (ETDEWEB)

    Trebossen, R. [CEA-Service Hospitalier Frederic-Joliot, 91 - Orsay (France)

    2007-04-15

    Since the recognition of the clinical value of Positron Emission Tomography (PET) for the diagnosis and staging of several cancers, the PET systems have evolved to systems associating PET and Computed Tomography (CT). The main constraint for clinical imaging is to reduce the acquisition duration. As a consequence, PET detectors are faster and emit more light than the BGO crystal used previously. These detectors allow an improvement of the count rate performance of the PET systems, reducing the scattered and the random events while increasing the true events at high activity concentration. Among the new crystals, some allow measuring the time of flight of the annihilation photons. This measurement further improves the performance of the systems. The spatial resolution of clinical PET systems is still equal to 5 mm at best. High spatial resolution PET systems dedicated to small animal imaging have been developed. These systems use similar crystal materials as the clinical systems. However, in order to permit spatial resolution close to 1 mm, the crystal elements have much smaller transverse dimensions than that of clinical systems. The detectors are compact using position sensitive photomultipliers or photodiodes. In order to preserve the uniformity of the spatial resolution over the transverse field of view of the tomography, solutions allowing the measurement of the depth of interaction of the photons in the crystal have been designed. New compact detectors based on semi conductors are currently investigated. (author)

  15. Kikuchi-Fujimoto disease mimicking tuberculous lymphadenitis or lymphoma on fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography

    Directory of Open Access Journals (Sweden)

    Abdul Rahim N

    2016-07-01

    Full Text Available Noraini Abdul Rahim,1 Abdul Jalil Nordin,2 Chiara Rusconi,3 Cristina Gabutti,3 Erika Ravelli,4 Claudio Rossetti5 1Diagnostic Imaging Department, Serdang Hospital, Selangor, 2Centre for Diagnostic Nuclear Imaging, University Putra Malaysia, Serdang, Malaysia; 3Department of Haematology, Ospedale Niguarda, Milan, 4Unit of Haematology, Valduce Hospital, Como, 5Department of Advance Technology (Nuclear Medicine, Ospedale Niguarda, Milan, Italy Abstract: Kikuchi-Fujimoto disease, also known as histiocytic lymphadenitis is a rare and benign disease characterized by regional cervical lymphadenopathy with fever of unknown origin, affecting mainly young women. We describe a case of a young Asian female who was initially misdiagnosed as having tuberculous lymphadenitis because of multiple lymphadenopathies with 18-fluorodeoxyglucose uptake on positron emission tomography/computed tomography. Final histologic diagnosis of Kikuchi-Fujimoto disease was made after excisional biopsy of the affected lymph node. The cervical lymphadenopathy has reduced in size and lung lesions disappeared after 2 months without specific treatment. Keywords: cervical lymphadenopathy, Kikuchi disease, PET/CT features

  16. Application of positron emission tomography/computed tomography in radiation treatment planning for head and neck cancers

    Institute of Scientific and Technical Information of China (English)

    Musaddiq; J; Awan; Farzan; Siddiqui; David; Schwartz; Jiankui; Yuan; Mitchell; Machtay; Min; Yao

    2015-01-01

    18-fluorodeoxygluocose positron emission tomography/computed tomography(18FDG-PET/CT) provides significant information in multiple settings in the management of head and neck cancers(HNC). This article seeks to define the additional benefit of PET/CT as related to radiation treatment planning for squamous cell carcinomas(SCCs) of the head and neck through a review of relevant literature. By helping further define both primary and nodal volumes, radiation treatment planning can be improved using PET/CT. Special attention is paid to the independent benefit of PET/CT in targeting mucosal primaries as well as in detecting nodal metastases. The utility of PET/CT is also explored for treatment planning in the setting of SCC of unknown primary as PET/CT may help define a mucosal target volume by guiding biopsies for examination under anesthesia thus changing the treatment paradigm and limiting the extent of therapy. Implications of the use of PET/CT for proper target delineation in patients with artifact from dental procedures are discussed and the impact of dental artifact on CT-based PET attenuation correction is assessed. Finally, comment is made upon the role of PET/CT in the high-risk post-operative setting, particularly in the context of radiation dose escalation. Real case examples are used in these settings to elucidate the practical benefits of PET/CT as related to radiation treatment planning in HNCs.

  17. Clinico-radiological correlation of Wilson's disease by magnetic resonance imaging, computed tomography and positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Ken; Sakata, Chigusa; Nemoto, Hiroshi; Yokoi, Fuji; Sunohara, Nobuhiko (National Center of Neurology and Psychiatry, Kodaira, Tokyo (Japan)); Iio, Masaaki

    1991-02-01

    Five patients with Wilson's disease received repeated magnetic resonance imaging (MRI) and computed tomography (CT) examinations at intervals from 6 to 29 months. Four patients, except for asymptomatic one, also underwent positron emission tomography (PET). The significance and limitations of these imaging modalities were examined in the light of their correlation with clinical manifestations and their therapeutic evaluation. The following focal regions, detected on MRI, had a strong positive correlation with clinical manifestations: the lenticular nuclei for dystonia, the brain stem for abnormality of smooth persuit eye movements, and the caudate and lenticular nuclei for severe dysarthria/dysphagia. Follow-up MRI for 3 patients showed an improvement of findings in the lenticular nuclei, lateral part of the putamen, and brain stem, that was in accordance with improved clinical or neurologic manifestations, such as dystonia and cerebellar symptoms. Severe abnormality in the caudate nucleus was associated with poor prognosis. Repeated CT failed to show serial changes in any of the patients. Regional blood flow and oxygen metabolic rate, obtained by PET examinations, were slightly decreased in the thalamus that had normal findings on both MRI and CT, as well as in the cerebral cortex and basal ganglia. PET was, however, inferior to MRI in detecting fine foci within the basal ganglia. In conclusion, there was a good correlation between MRI findings, particularly foci of the caudate and lenticular nuclei, and clinical manifestations. Repeated MRI examinations were the most useful approach to the evaluation of therapeutic effects and prognosis. (N.K.).

  18. Regional myocardial blood flow, metabolism and function assessed noninvasively by positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Schelbert, H.R.; Phelps, M.E.; Hoffman, E.; Huang, S.; Kuhl, D.E.

    1979-01-01

    Positron emission computed tomography is a new technique for the noninvasive measure of myocardial blood flow, mechanical function and, in particular, metabolism. The capability of this new study means is due to the technological innovations of the imaging device and the availability of radioactive tracers that are specific for blood flow and metabolism. The device permits recording of cross-sectional images of the left ventricular myocardium that reflect quantitatively regional tracer tissue concentrations. By employing tracer kinetic models this new technique permits the measurement of regional glucose and fatty acid metabolism of the heart. While already an important new tool for investigative studies into cardiac physiology and pathophysiology, the clinical utility of positron emission tomography remains to be defined.

  19. Positron emission tomography scanning is coming to a hospital near you soon!

    Science.gov (United States)

    Bashir, Humayun; Shabo, Gregory; Nunan, T O

    2008-04-01

    Positron emission tomography (PET) is still generally not available in the UK; however, there are plans to introduce a national service in England from April 2008. Plans are also at an advanced stage in Scotland and Wales. The main uses of PET are in preoperative staging of lung cancer, detection of recurrent colorectal cancer, and management of patients with lymphoma. Although these provide the bulk of the referral base, PET is also of use in specific situations in patients with less common cancers, such as head and neck cancer, gynaecological cancer, and melanoma. In its more common uses, PET has been shown to be cost effective. Positron emission tomography will play an increasing role in the evaluation of response to treatment to enable early separation of patients who are responding well to chemotherapy from those who are not responding and need to be transferred to another therapy.

  20. 99mTc-methylene diphosphonate single-photon emission computed tomography/computed tomography improves the diagnostic accuracy of osteoid osteoma

    Science.gov (United States)

    Squier, Samuel Brian; Lewis, Jacob Ian; Accurso, Joseph Matthew; Jain, Manoj Kumar

    2016-01-01

    We present a case of a 17-year-old football player who had previously received multiple facet joint injections for presumed secondary osteoarthritis. 99mTc-methylene diphosphonate single-photon emission computed tomography/computed tomography imaging of the cervical spine demonstrated focal increased radiopharmaceutical activity in the right C2 lamina, which was associated with an osteolytic lesion with a central irregular sclerotic nidus. Surgical pathology confirmed an osteoid osteoma. PMID:27833319

  1. (18)F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography in Malignancies of the Thyroid and in Head and Neck Squamous Cell Carcinoma

    DEFF Research Database (Denmark)

    Lauridsen, Jeppe Kiilerich; Rohde, Max; Thomassen, Anders

    2015-01-01

    18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) is a valuable diagnostic tool in a spectrum of malignant and benign conditions, because of a high sensitivity to detect even very small lesions with increased metabolism. This review focuses on the use of FDG-PET......-PET/CT in malignancies of the thyroid gland and in head and neck squamous cell carcinoma....

  2. Pancreatic tuberculosis: Evaluation of therapeutic response using F-18 fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography.

    Science.gov (United States)

    Santhosh, Sampath; Bhattacharya, Anish; Rana, Surinder Singh; Bhasin, Deepak Kumar; Srinivasan, Radhika; Mittal, Bhagwant Rai

    2014-10-01

    F-18 fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG PET/CT) is a functional imaging technique that monitors glucose metabolism in tissues. Pulmonary tuberculosis (TB) has been reported to show intense uptake of FDG, with a decrease in metabolism of the tuberculous lesions after successful anti-tubercular treatment (ATT). The authors present a patient with pancreatic TB and demonstrate the usefulness of FDG PET/CT in monitoring the response to ATT.

  3. Noninvasive evaluation of active pan-ulcerative colitis with multiple strictures using Fluorine-18-Fluorodeoxyglucose positron emission tomography/computed tomography.

    Science.gov (United States)

    Santhosh, Sampath; Bhattacharya, Anish; Rana, Surinder Singh; Bhasin, Deepak Kumar; Gupta, Rajesh; Mittal, Bhagwant Rai

    2016-01-01

    Ulcerative colitis (UC) is an inflammatory bowel disease characterized by waxing and waning inflammation that changes in severity and extent and may progress to neoplasia, especially in the presence of strictures. When patients have nonnegotiable strictures or severe inflammation with ulcers, colonoscopy is difficult and carries the risk of perforation. The authors present a patient with pan-UC with multiple strictures, in whom fluorodeoxyglucose positron emission tomography/computed tomography was used to noninvasively evaluate the extent and severity of the disease.

  4. Review of cardiovascular imaging in the journal of nuclear cardiology in 2015. Part 1 of 2: Plaque imaging, positron emission tomography, computed tomography, and magnetic resonance.

    Science.gov (United States)

    AlJaroudi, Wael A; Hage, Fadi G

    2016-02-01

    In 2015, many original articles pertaining to cardiovascular imaging with impressive quality were published in the Journal of Nuclear Cardiology. In a set of 2 articles, we provide an overview of these contributions to facilitate for the interested reader a quick review of the advancements that occurred in the field over this year. In this first article, we focus on arterial plaque imaging, cardiac positron emission tomography, computed tomography, and magnetic resonance imaging.

  5. 18F-fluorodeoxyglucose positron emission tomography-computed tomography finding of left gonadal vein thrombosis in a case of renal cell carcinoma.

    Science.gov (United States)

    Narayan, Ravishwar; Ravishankar, Uma; Natarajan, Savita; Vohra, Sandeep

    2016-01-01

    Tumor thrombus from renal cell carcinoma is commonly reported in renal vein and inferior vena cava with a few reports of gonadal vein involvement. Here, we report a case of an elderly female who underwent fluorodeoxyglucose (FDG) positron emission tomography-computed tomography scan for initial staging of left renal cell carcinoma. Along with an FDG avid left renal mass lesion, scan also revealed FDG avid tumor thrombus in the entire length of the left gonadal vein.

  6. When to perform positron emission tomography/computed tomography or radionuclide bone scan in patients with recently diagnosed prostate cancer

    Directory of Open Access Journals (Sweden)

    Caldarella C

    2013-06-01

    Full Text Available Carmelo Caldarella,1 Giorgio Treglia,2 Alessandro Giordano,1 Luca Giovanella2 1Institute of Nuclear Medicine, Catholic University of the Sacred Heart, Rome, Italy; 2Department of Nuclear Medicine and PET/CT Centre, Oncology Institute of Southern Switzerland, Bellinzona, Switzerland Abstract: Skeletal metastases are very common in prostate cancer and represent the main metastatic site in about 80% of prostate cancer patients, with a significant impact in patients' prognosis. Early detection of bone metastases is critical in the management of patients with recently diagnosed high-risk prostate cancer: radical treatment is recommended in case of localized disease; systemic therapy should be preferred in patients with distant secondary disease. Bone scintigraphy using radiolabeled bisphosphonates is of great importance in the management of these patients; however, its main drawback is its low overall accuracy, due to the nonspecific uptake in sites of increased bone turnover. Positron-emitting radiopharmaceuticals, such as fluorine-18-fluorodeoxyglucose, choline-derived drugs (fluorine-18-fluorocholine and carbon-11-choline and sodium fluorine-18-fluoride, are increasingly used in clinical practice to detect metastatic spread, and particularly bone involvement, in patients with prostate cancer, to reinforce or substitute information provided by bone scan. Each radiopharmaceutical has a specific mechanism of uptake; therefore, diagnostic performances may differ from one radiopharmaceutical to another on the same lesions, as demonstrated in the literature, with variable sensitivity, specificity, and overall accuracy values in the same patients. Whether bone scintigraphy can be substituted by these new methods is a matter of debate. However, greater radiobiological burden, higher costs, and the necessity of an in-site cyclotron limit the use of these positron emission tomography methods as first-line investigations in patients with prostate cancer

  7. {sup 18}F-fluorodeoxyglucose positron emission tomography and computed tomography in anaplastic thyroid cancer

    Energy Technology Data Exchange (ETDEWEB)

    Poisson, Thomas [Institut Gustave Roussy and University Paris-Sud XI, Department of Nuclear Medicine and Endocrine Oncology, Villejuif Cedex (France); Service de Medecine Nucleaire, Hopital Bichat, Paris (France); Deandreis, Desiree; Leboulleux, Sophie; Lumbroso, Jean; Baudin, Eric [Institut Gustave Roussy and University Paris-Sud XI, Department of Nuclear Medicine and Endocrine Oncology, Villejuif Cedex (France); Bidault, Francois [Institut Gustave Roussy and University Paris-Sud XI, Department of Radiology, Villejuif Cedex (France); Bonniaud, Guillaume [Institut Gustave Roussy and University Paris-Sud XI, Department of Medical Physics, Villejuif Cedex (France); Baillot, Sylvain; Auperin, Anne [Institut Gustave Roussy and University Paris-Sud XI, Department of Epidemiology, Villejuif Cedex (France); Ghuzlan, Abir Al [Institut Gustave Roussy and University Paris-Sud XI, Department of Pathology, Villejuif Cedex (France); Travagli, Jean-Paul [Institut Gustave Roussy and University Paris-Sud XI, Department of Endocrine Surgery, Villejuif Cedex (France); Schlumberger, Martin [Institut Gustave Roussy and University Paris-Sud XI, Department of Nuclear Medicine and Endocrine Oncology, Villejuif Cedex (France); Institut Gustave Roussy, Service de Medecine Nucleaire et de Cancerologie Endocrinienne, Villejuif (France)

    2010-12-15

    Our aim was to evaluate in anaplastic thyroid carcinoma (ATC) patients the value of {sup 18}F-FDG PET/CT compared with total body computed tomography (CT) using intravenous contrast material for initial staging, prognostic assessment, therapeutic monitoring and follow-up. Twenty consecutive ATC patients underwent PET/CT for initial staging. PET/CT was performed again during follow-up. The gold standard was progression on imaging follow-up (CT or PET/CT) or confirmation with another imaging modality. A total of 265 lesions in 63 organs were depicted in 18 patients. Thirty-five per cent of involved organs were demonstrated only with PET/CT and one involved organ only with CT. In three patients, the extent of disease was significantly changed with PET/CT that demonstrated unknown metastases. Initial treatment modalities were modified by PET/CT findings in 25% of cases. The volume of FDG uptake ({>=}300 ml) and the intensity of FDG uptake (SUV{sub max} {>=}18) were significant prognostic factors for survival. PET/CT permitted an earlier assessment of tumour response to treatment than CT in 4 of the 11 patients in whom both examinations were performed. After treatment with combined radiotherapy and chemotherapy, only the two patients with a negative control PET/CT had a confirmed complete remission at 14 and 38 months; all eight patients who had persistent FDG uptake during treatment had a clinical recurrence and died. FDG PET/CT appears to be the reference imaging modality for ATC at initial staging and seems promising in the early evaluation of treatment response and follow-up. (orig.)

  8. Usefulness of myocardial positron emission tomography/nuclear imaging in Takotsubo cardiomyopathy

    Institute of Scientific and Technical Information of China (English)

    Marzia; Testa; Mauro; Feola

    2014-01-01

    AIM:To analyse and summarize all the articles related to positron emission tomography and Takotsubo cardiomyopathy(TTC).METHODS:We performed a systematic review of the existing literature on positron emission tomography/nuclear imaging and Takotsubo cardiomyopathy using PUBMED database.We combined search terms such as"takotsubo","takotsubo syndrome","myocardial positron emission tomography","positron emission tomography".All case reports were excluded.The list included only four articles which were reviewed by two independent investigators.It was not possible to undertake a formal meta-analysis because of the heterogeneity of the studies;therefore,we made a narrative synthesis of the collected data.RESULTS:Nuclear medicine techniques can be useful employed in the differential diagnosis of TTC from an acute coronary syndrome(ACS).In fact,transient left ventricular(LV)apical ballooning is a syndrome frequently misdiagnosed as an ACS and can mimic symptoms of myocardial infarction with ST-T segments changes on electrocardiography(ECG),a limited re-lease of myocardial enzyme,mainly reported after sudden emotional or physical stress,and an akinesis or dyskinesis of the left ventricle apex which are completely reversible in a few weeks.In the studies included in this review,nuclear medicine techniques have demonstrated a discrepancy between normal perfusion and a reduced glucose utilization in TTC,commonly known as"inverse flow metabolism mismatch".This suggests that apical ballooning represents a transient metabolic disorder on the cellular level,rather than a structural contractile disease of the myocardium,due to a transient decrease of glucose metabolism that might be related to a coronary microcirculation impairment followed by prolonged myocardial stunning.CONCLUSION:Nuclear medicine techniques can be usefully used for the diagnosis of TTC and can increase our knowledge of the pathophysiological mechanisms of TTC.

  9. The establishment of crystal position look-up table for positron emission tomography with block detectors

    Institute of Scientific and Technical Information of China (English)

    CHAI Pei; SHAN BaoCi

    2009-01-01

    A method has been developed to establish the crystal position look-up table for positron emission tomography with block detectors.It is based on the principle that the counts in crystal position histogram obey the Gaussian mixture model(GMM).This method has taken full consideration of the characteristics of the GMM and the detector itself.The experimental results have proved that it is simple,reliable,and universal.

  10. Advances in Single-Photon Emission Computed Tomography Hardware and Software.

    Science.gov (United States)

    Piccinelli, Marina; Garcia, Ernest V

    2016-02-01

    Nuclear imaging techniques remain today's most reliable modality for the assessment and quantification of myocardial perfusion. In recent years, the field has experienced tremendous progress both in terms of dedicated cameras for cardiac applications and software techniques for image reconstruction. The most recent advances in single-photon emission computed tomography hardware and software are reviewed, focusing on how these improvements have resulted in an even more powerful diagnostic tool with reduced injected radiation dose and acquisition time.

  11. Imaging Chronic Pain and Inflammation : Positron Emission Tomography Studies of Whiplash Associated Disorder

    OpenAIRE

    2008-01-01

    This thesis is on chronic neck pain after a rear impact car injury, so called whiplash associated disorder (WAD). Three empirical studies using positron emission tomography (PET) with different radioligands have been performed. The first study evaluated resting state regional cerebral blood flow (rCBF) in WAD patients and in healthy, pain-free controls, by use of oxygen-15 labeled water. Patients had heightened resting rCBF bilaterally in the posterior parahippocampal and the posterior cingul...

  12. Fluorodeoxyglucose positron emission tomography in the evaluation of germ cell tumours at relapse

    OpenAIRE

    Hain, S F; O’Doherty, M J; Timothy, A R; Leslie, M D; Harper, P. G.; Huddart, R A

    2000-01-01

    Differentiation of active disease from fibrosis/mature teratoma in patients with residual masses or identifying of sites of recurrence in patients with raised markers following treatment of their testicular cancer remains a problem.18F-fluorodeoxyglucose positron emission tomography (FDG-PET) has the potential to identify active disease and thereby influence further management in these patients. We performed a retrospective study of the use of FDG-PET in detecting residual/recurrent testicula...

  13. The prognostic value of positron emission tomography in non-small cell lung cancer : Analysis of 266 cases

    NARCIS (Netherlands)

    Kramer, H.; Post, W.J.; Pruim, J.; Groen, H.J.M.

    2006-01-01

    Positron emission tomography (PET) is more accurate than computed tomography (CT) in the staging of non-small cell lung cancer (NSCLC). We analyzed the prognostic value of PET for survival in NSCLC patients. Methods: Consecutive patients with proven NSCLC with PET for staging were selected. Staging

  14. Targeted positron emission tomography imaging of CXCR4 expression in patients with acute myeloid leukemia.

    Science.gov (United States)

    Herhaus, Peter; Habringer, Stefan; Philipp-Abbrederis, Kathrin; Vag, Tibor; Gerngross, Carlos; Schottelius, Margret; Slotta-Huspenina, Julia; Steiger, Katja; Altmann, Torben; Weißer, Tanja; Steidle, Sabine; Schick, Markus; Jacobs, Laura; Slawska, Jolanta; Müller-Thomas, Catharina; Verbeek, Mareike; Subklewe, Marion; Peschel, Christian; Wester, Hans-Jürgen; Schwaiger, Markus; Götze, Katharina; Keller, Ulrich

    2016-08-01

    Acute myeloid leukemia originates from leukemia-initiating cells that reside in the protective bone marrow niche. CXCR4/CXCL12 interaction is crucially involved in recruitment and retention of leukemia-initiating cells within this niche. Various drugs targeting this pathway have entered clinical trials. To evaluate CXCR4 imaging in acute myeloid leukemia, we first tested CXCR4 expression in patient-derived primary blasts. Flow cytometry revealed that high blast counts in patients with acute myeloid leukemia correlate with high CXCR4 expression. The wide range of CXCR4 surface expression in patients was reflected in cell lines of acute myeloid leukemia. Next, we evaluated the CXCR4-specific peptide Pentixafor by positron emission tomography imaging in mice harboring CXCR4 positive and CXCR4 negative leukemia xenografts, and in 10 patients with active disease. [(68)Ga]Pentixafor-positron emission tomography showed specific measurable disease in murine CXCR4 positive xenografts, but not when CXCR4 was knocked out with CRISPR/Cas9 gene editing. Five of 10 patients showed tracer uptake correlating well with leukemia infiltration assessed by magnetic resonance imaging. The mean maximal standard uptake value was significantly higher in visually CXCR4 positive patients compared to CXCR4 negative patients. In summary, in vivo molecular CXCR4 imaging by means of positron emission tomography is feasible in acute myeloid leukemia. These data provide a framework for future diagnostic and theranostic approaches targeting the CXCR4/CXCL12-defined leukemia-initiating cell niche.

  15. Effect of tissue heterogeneity on quantification in positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Blomqvist, G. [Dept. of Clinical Neuroscience, Experimental Alcohol and Drug Addiction Research Section, Karolinska Hospital, Stockholm (Sweden); Lammertsma, A.A. [PET Methodology Group, Cyclotron Unit, MRC Clinical Sciences Centre, Royal Postgraduate Medical School, Hammersmith Hospital, London (United Kingdom); Mazoyer, B. [Service Hospitalier Frederic Joliot CEA/Dept. de Biologie, Hopital d`Orsay and Antenne d`Informatique Medicale, Hopital Robert Debre, Paris (France); Wienhard, K. [Max-Planck-Inst. fuer Neurologische Forschung, Koeln (Germany)

    1995-07-01

    As a result of the limited spatial resolution of positron emission tomographic scanners, the measurements of physiological parameters are compromised by tissue heterogeneity. The effect of tissue heterogeneity on a number of parameters was studied by simulation and an analytical method. Five common tracer models were assessed. The input and tissue response functions were assumed to be free from noise and systematic errors. The kinetic model was assumed to be perfect. Two components with different kinetics were mixed in different proportions and contrast with respect to the model parameters. Different experimental protocols were investigated. Of three methods investigated for the measurement of cerebral blood flow (CBF) (steady state, dynamic, integral), the second one was least sensitive to errors caused by tissue heterogeneity and the main effect was an underestimation of the distribution volume. With the steady state method, errors in oxygen extraction fraction caused by tissue heterogeneity were always found to be less than the corresponding errors in CBF. For myocardial blood flow the steady state method was found to perform better than the bolus method. The net accumulation of substrate (i.e. rCMR{sub glc} in the case of glucose analogs) was found to be comparatively insensitive to tissue heterogeneity. Individual rate constans such as k{sub 2} and k{sub 3} for efflux and metabolism of the substrate in the pool of unmetabolized substrate in the tissue, respectively, were found to be more sensitive. In studies of radioligand binding, using only tracer doses, the effect of tissue heterogeneity on the parameter k{sub on}.B{sub max} could be considerable. In studies of radioligand binding using a protocol with two experiments, one with high and one with low specific activity, B{sub max} was found to be insensitive while K{sub d} was very sensitive to tissue heterogeneity. (orig.)

  16. Combined use of positron emission tomography and volume doubling time in lung cancer screening with low-dose CT scanning

    DEFF Research Database (Denmark)

    Ashraf, H; Dirksen, A; Jakobsen, Annika Loft

    2011-01-01

    In lung cancer screening the ability to distinguish malignant from benign nodules is a key issue. This study evaluates the ability of positron emission tomography (PET) and volume doubling time (VDT) to discriminate between benign and malignant nodules.......In lung cancer screening the ability to distinguish malignant from benign nodules is a key issue. This study evaluates the ability of positron emission tomography (PET) and volume doubling time (VDT) to discriminate between benign and malignant nodules....

  17. 18F-FLT Positron Emission Tomography/Computed Tomography Imaging in Pancreatic Cancer: Determination of Tumor Proliferative Activity and Comparison with Glycolytic Activity as Measured by 18F-FDG Positron Emission Tomography/Computed Tomography Imaging

    Directory of Open Access Journals (Sweden)

    Senait Aknaw Debebe

    2016-02-01

    Full Text Available Objective: This phase-I imaging study examined the imaging characteristic of 3’-deoxy-3’-(18F-fluorothymidine (18F-FLT positron emission tomography (PET in patients with pancreatic cancer and comparisons were made with (18F-fluorodeoxyglucose (18F-FDG. The ultimate aim was to develop a molecular imaging tool that could better define the biologic characteristics of pancreas cancer, and to identify the patients who could potentially benefit from surgical resection who were deemed inoperable by conventional means of staging. Methods: Six patients with newly diagnosed pancreatic cancer underwent a combined FLT and FDG computed tomography (CT PET/CT imaging protocol. The FLT PET/CT scan was performed within 1 week of FDG PET/CT imaging. Tumor uptake of a tracer was determined and compared using various techniques; statistical thresholding (z score=2.5, and fixed standardized uptake value (SUV thresholds of 1.4 and 2.5, and applying a threshold of 40% of maximum SUV (SUVmax and mean SUV (SUVmean. The correlation of functional tumor volumes (FTV between 18F-FDG and 18F-FLT was assessed using linear regression analysis. Results: It was found that there is a correlation in FTV due to metabolic and proliferation activity when using a threshold of SUV 2.5 for FDG and 1.4 for FLT (r=0.698, p=ns, but a better correlation was obtained when using SUV of 2.5 for both tracers (r=0.698, p=ns. The z score thresholding (z=2.5 method showed lower correlation between the FTVs (r=0.698, p=ns of FDG and FLT PET. Conclusion: Different tumor segmentation techniques yielded varying degrees of correlation in FTV between FLT and FDGPET images. FLT imaging may have a different meaning in determining tumor biology and prognosis.

  18. Comparison of {sup 18}F-fluorodeoxyglucose positron emission tomography/computed tomography, hydro-stomach computed tomography, and their combination for detecting primary gastric cancer

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Hye Young; Chung, Woo Suk; Song, E Rang; Kim, Jin Suk [Konyang University Myunggok Medical Research Institute, Konyang University Hospital, Konyang University College of Medicine, Daejeon (Korea, Republic of)

    2015-01-15

    To retrospectively compare the diagnostic accuracy for detecting primary gastric cancer on positron emission tomography/computed tomography (PET/CT) and hydro-stomach CT (S-CT) and determine whether the combination of the two techniques improves diagnostic performance. A total of 253 patients with pathologically proven primary gastric cancer underwent PET/CT and S-CT for the preoperative evaluation. Two radiologists independently reviewed the three sets (PET/CT set, S-CT set, and the combined set) of PET/CT and S-CT in a random order. They graded the likelihood for the presence of primary gastric cancer based on a 4-point scale. The diagnostic accuracy of the PET/CT set, the S-CT set, and the combined set were determined by the area under the alternative-free receiver operating characteristic curve, and sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Diagnostic accuracy, sensitivity, and NPV for detecting all gastric cancers and early gastric cancers (EGCs) were significantly higher with the combined set than those with the PET/CT and S-CT sets. Specificity and PPV were significantly higher with the PET/CT set than those with the combined and S-CT set for detecting all gastric cancers and EGCs. The combination of PET/CT and S-CT is more accurate than S-CT alone, particularly for detecting EGCs.

  19. Characterization of pulmonary lesions in patients with suspected lung cancer: computed tomography versus [¹⁸F] fluorodeoxyglucose-positron emission tomography/computed tomography.

    Science.gov (United States)

    Harders, Stefan Walbom; Madsen, Hans Henrik; Hjorthaug, Karin; Arveschoug, Anne Kirstine; Rasmussen, Torben Riis; Meldgaard, Peter; Andersen, Johanne Bach; Pilegaard, Hans Kristian; Hager, Henrik; Rehling, Michael; Rasmussen, Finn

    2012-10-16

    Pulmonary nodules are of high clinical importance, given they may prove to be an early manifestation of lung cancer. Pulmonary nodules are small, focal, radiographic opacities that may be solitary or multiple. A solitary pulmonary nodule is a single, small (pulmonary nodules remains unclear. However, the question of malignancy of any given nodule remains the same. A standard contrast-enhanced computed tomography (CT) scan is often the first examination, followed by a number of other examinations. The purpose of this study was to examine the clinical feasibility of CT versus integrated [18F]fluorodeoxyglucose-positron emission tomography (PET)/low-dose CT scan in patients with suspected lung cancer and pulmonary lesions on CT. All results were controlled for reproducibility. We found that when used early in the work-up of the lesions, CT raised the prevalence of lung cancer in the population to the point where further diagnostic imaging examination could be considered futile. We also found that the overall diagnostic accuracy, as well as the classification probabilities and predictive values of the two modalities were not significantly different; the reproducibility of these results was substantial.

  20. The contribution of single photon emission computed tomography in the clinical assessment of Alzheimer type dementia; Apport de la tomographie d'emission monophonique cerebrale dans l'evaluation des demences de type Alzheimer

    Energy Technology Data Exchange (ETDEWEB)

    Boudousq, V.; Collombier, L.; Kotzki, P.O. [Centre Hospitalier Universitaire de Nimes, 30 (France)

    1999-12-01

    Interest of brain single-photon emission computed tomography to support clinical diagnosis of Alzheimer-type dementia is now established. Numerous studies have reported a decreased perfusion in the association cortex of the parietal lobe and the posterior temporal regions. In patients with mild cognitive complaints, the presence of focal hypoperfusion may increase substantially the probability of the disease. In addition, emission tomography emerges as a helpful tool in situation in which there is diagnostic doubt. In this case, the presence of temporo-parietal perfusion deficit associated with hippocampal atrophy on MRI or X-ray computed tomography contributes to diagnostic accuracy. However, some studies suggest that emission tomography may be useful for preclinical prediction of Alzheimer's disease and to predict cognitive decline. (author)

  1. Positron emission tomography in digestive neuroendocrine tumors: choice of the tracer; Apport de la tomographie par emission de positons dans les tumeurs endocrines digestives: choix du traceur

    Energy Technology Data Exchange (ETDEWEB)

    Taieb, D.; Tessonnier, L.; Mundler, O. [Centre Hospitalo-Universitaire de La Timone, Service Central de Biophysique et de Medecine Nucleaire, 13 - Marseille (France)

    2009-11-15

    Digestive endocrine tumors represent a heterogeneous group of neoplasm sharing common characteristics such as their high density of peptide receptors, their ability to take up amino acids and de-carboxylate them into biogenic amines and their low glycolytic activity. These features are used for nuclear imaging targeting. To date, somatostatin receptor scintigraphy is considered the 'gold standard' imaging procedure of well-differentiated tumors. Despite the significant contribution of SPECT/CT, the use of positron emission tomography imaging (PET) is growing rapidly. Three PET imaging modalities are currently available: {sup 68}Ga-labeled somatostatin analogs PET, {sup 18}F-dihydroxy-phenylalanine PET ({sup 18}F-DOPA) and {sup 18}F-deoxyglucose PET ({sup 18}F-F.D.G.). This article focuses on the current targets of molecular imaging and highlights the potential clinical applications of new targets. (authors)

  2. Non-oncological positron emission tomography (PET): brain imaging; La tomographie par emission de positons (TEP) hors oncologie: l'exploration du cerveau

    Energy Technology Data Exchange (ETDEWEB)

    Lomena, F. [Centro de Diagnostico por la imagen (CDIC), Hospital Clinic, Servicio de medicina nuclear, Barcelona (Spain)

    2008-10-15

    Positron emission tomography (PET) allows evaluation of the central nervous system function. Imaging of regional cerebral blood flow and metabolism, and of several neurotransmission systems may be obtained using PET. PET quantification is accurate and has good test-retest reliability. For research purposes, PET has been used to study brain physiology, to explore neurological and psychiatric diseases pathophysiology and for the new drugs research and development. F.D.G. is the only PET radioligand with clinical application. Following criteria of evidence-based medicine, the clinical indications of F.D.G.-PET are: evaluation of treated gliomas, pre surgical study of partial refractory epilepsy and diagnosis of Alzheimer's disease when it is impossible to differentiate clinically from fronto-temporal dementia.

  3. DIRECT OBSERVATION OF SOLAR CORONAL MAGNETIC FIELDS BY VECTOR TOMOGRAPHY OF THE CORONAL EMISSION LINE POLARIZATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Kramar, M. [Physics Department, The Catholic University of America, 620 Michigan Avenue NE, Washington, DC 20064 (United States); Lin, H. [Institute for Astronomy, University of Hawaii at Manoa, 34 Ohia Ku Street, Pukalani, Maui, HI 96768 (United States); Tomczyk, S., E-mail: kramar@cua.edu, E-mail: lin@ifa.hawaii.edu, E-mail: tomczyk@ucar.edu [High Altitude Observatory, 3080 Center Green Drive, Boulder, CO 80301 (United States)

    2016-03-10

    We present the first direct “observation” of the global-scale, 3D coronal magnetic fields of Carrington Rotation (CR) Cycle 2112 using vector tomographic inversion techniques. The vector tomographic inversion uses measurements of the Fe xiii 10747 Å Hanle effect polarization signals by the Coronal Multichannel Polarimeter (CoMP) and 3D coronal density and temperature derived from scalar tomographic inversion of Solar Terrestrial Relations Observatory (STEREO)/Extreme Ultraviolet Imager (EUVI) coronal emission lines (CELs) intensity images as inputs to derive a coronal magnetic field model that best reproduces the observed polarization signals. While independent verifications of the vector tomography results cannot be performed, we compared the tomography inverted coronal magnetic fields with those constructed by magnetohydrodynamic (MHD) simulations based on observed photospheric magnetic fields of CR 2112 and 2113. We found that the MHD model for CR 2112 is qualitatively consistent with the tomography inverted result for most of the reconstruction domain except for several regions. Particularly, for one of the most noticeable regions, we found that the MHD simulation for CR 2113 predicted a model that more closely resembles the vector tomography inverted magnetic fields. In another case, our tomographic reconstruction predicted an open magnetic field at a region where a coronal hole can be seen directly from a STEREO-B/EUVI image. We discuss the utilities and limitations of the tomographic inversion technique, and present ideas for future developments.

  4. Prediction of positron emission tomography/computed tomography (PET/CT) positivity in patients with high-risk primary melanoma

    Science.gov (United States)

    Danielsen, Maria; Kjaer, Andreas; Wu, Max; Martineau, Lea; Nosrati, Mehdi; Leong, Stanley PL; Sagebiel, Richard W; III, James R Miller; Kashani-Sabet, Mohammed

    2016-01-01

    Positron emission tomography/computed tomography (PET/CT) is an important tool to identify occult melanoma metastasis. To date, it is controversial which patients with primary cutaneous melanoma should have staging PET/CT. In this retrospective analysis of more than 800 consecutive patients with cutaneous melanoma, we sought to identify factors predictive of PET/CT positivity in the setting of newly-diagnosed high-risk primary melanoma to determine those patients most appropriate to undergo a PET/CT scan as part of their diagnostic work up. 167 patients with newly-diagnosed high-risk primary cutaneous melanoma underwent a PET/CT scan performed as part of their initial staging. Clinical and histologic factors were evaluated as possible predictors of melanoma metastasis identified on PET/CT scanning using both univariate and multivariate logistic regression. In all, 32 patients (19.2%) had a positive PET/CT finding of metastatic melanoma. In more than half of these patients (56.3%), PET/CT scanning identified disease that was not detectable on clinical examination. Mitotic rate, tumor thickness, lymphadenopathy, and bleeding were significantly predictive of PET/CT positivity. A combinatorial index constructed from these factors revealed a significant association between number of high-risk factors observed and prevalence of PET/CT positivity, which increased from 5.8% (with the presence of 0-2 factors) to 100.0%, when all four factors were present. These results indicate that combining clinical and histologic prognostic factors enables the identification of patients with a higher likelihood of a positive PET/CT scan.

  5. Whole-body positron emission tomography using fluorodeoxyglucose for staging of lymphoma: effectiveness and comparison with computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Stumpe, K.D.M.; Urbinelli, M.; Steinert, H.C.; Glanzmann, C.; Buck, A.; von Schulthess, G.K. [Department of Medical Radiology, University Hospital, Zurich (Switzerland)

    1998-07-01

    The purpose of this study was to evaluate whole-body positron emission tomography (WB-PET) as a staging modality in Hodgkin`s disease (HD) and non-Hodgkin lymphoma (NHL) and to compare it with computed tomography (CT) in a retrospective study. Seventy-one WB-PET studies using fluorodeoxyglucose (FDG) and 49 CT examinations were performed in 19 women and 31 men. Transaxial images were acquired and reformatted coronally and sagittally in PET. CT sections were obtained from the skull base to the pelvic floor. The written reports of the imaging data were compared with a reference standard constructed on the basis of all the data on the individual patients, including clinical follow-up of at least 6 months. The sensitivity and specificity of PET were, respectively, 86% and 96% for HD (n=53), and 89% and 100% for NHL (n=18). For CT sensitivity and specificity were 81% and 41% for HD (n=33) and 86% and 67% for NHL (n=16). Differences between PET and CT sensitivities were not significant, while in HD there was a significant difference in the specificity of PET and CT examinations, mainly because CT was unable to distinguish between active or recurrent disease and residual scar tissue after therapy. FDG tumour uptake was found in high- as well as low-grade NHL patients. In conclusion, PET appears to be highly sensitive and specific for staging of lymphoma. It is at least as sensitive as CT, and more specific, particularly in patients undergoing restaging, where a well-recognized diagnostic dilemma in CT is the presence of a post-therapeutic residual mass. (orig.) With 4 figs., 3 tabs., 23 refs.

  6. Clinical applications of 18F-fluorodeoxyglucose positron emission tomography/computed tomography in carcinoma of unknown primary

    Institute of Scientific and Technical Information of China (English)

    HU Man; YU Jin-ming; ZHAO Wei; ZHANG Pin-liang; JU Gui-fang; FU Zheng; ZHANG Guo-li; KONG Li; YANG Yan-qin; MA Yi-dong

    2011-01-01

    Background Carcinoma of unknown primary (CUP) encompasses a heterogeneous group of tumors with varying clinical features. The management of patients of CUP remains a clinical challenge. The purpose of this study was to evaluate the clinical applications of integrated 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) information in patients with CUP,including detecting the occult primary tumor and effecting on disease therapy.Methods One hundred and forty-nine patients with histologically-proven metastases of CUP were included. For all patients,the conventional diagnostic work-up was unsuccessful in localizing the primary site. Whole-body PET/CT images were obtained approximately 60 minutes after intravenous injection of 350-425 MBq of 18F-FDG.Results In 24.8% of patients,FDG PET/CT detected primary tumors that were not apparent after conventional workup.In this group of patients,the overall sensitivity,specificity,and accuracy rates of FDG PET/CT in detecting unknown primary tumors were 86.0%,87.7%,and 87.2%,respectively. FDG PET/CT imaging also led to the detection of previously unrecognized metastases in 29.5% of patients. Forty-seven (31.5%,47 of 149) patients underwent a change in therapeutic management.Conclusions FDG PET/CT is a valuable tool in patients with CUP,because it assisted in detecting unknown primary tumors and previously unrecognized distant metastases,and optimized the mangement of these patients.

  7. Whole body muscle activity during the FIFA 11+ program evaluated by positron emission tomography.

    Directory of Open Access Journals (Sweden)

    Junsuke Nakase

    Full Text Available PURPOSE: This study investigated the effect of the FIFA 11+ warm-up program on whole body muscle activity using positron emission tomography. METHODS: Ten healthy male volunteers were divided into a control group and a group that performed injury prevention exercises (The 11+. The subjects of the control group were placed in a sitting position for 20 min and 37 MBq of (18F-fluorodeoxyglucose (FDG was injected intravenously. The subjects then remained seated for 45 min. The subjects of the exercise group performed part 2 of the 11+for 20 min, after which FDG was injected. They then performed part 2 of the 11+for 20 min, and rested for 25 min in a sitting position. Positron emission tomography-computed tomography images were obtained 50 min after FDG injection in each group. Regions of interest were defined within 30 muscles. The standardized uptake value was calculated to examine the FDG uptake of muscle tissue per unit volume. RESULTS: FDG accumulation within the abdominal rectus, gluteus medius and minimus were significantly higher in the exercise group than in the control group (P<0.05. CONCLUSION: The hip abductor muscles and abdominal rectus were active during part 2 of the FIFA 11+ program.

  8. Early detection of response to imatinib therapy for gastrointestinal stromal tumor by using 18F-FDG-positron emission tomography and computed tomography imaging

    Institute of Scientific and Technical Information of China (English)

    Sabri Zincirkeser; Alper Sevinc; M Emin Kalender; Celalettin Camci

    2007-01-01

    A 41-year old female with metastatic gastrointestinal stromal tumor was referred to 18F-FDG-positron emission tomography and computed tomography (PET/CT) scan before and after one-month treatment with imatinib(Glivec(R), Gleevec(R), Novartis, Basel, Switzerland), a tyrosine kinase inhibitor (400 mg/d). Metabolic response was evaluated before and after one month of therapy. The decrease of the maximum standardised uptake value (SUV)was 79% (from 9.8 to 2.1). Positron emission tomography demonstrated complete metabolic response after one-month of imatinib treatment. Additionally, the previous lesion was compared with the coronal computerized tomographic image. There was no difference in the size of the tumor before and after therapy according to CT images. However, metabolic activity was inhibited.18F-FDG-PET is a valuable method for the detection of response to one-month imatinib treatment in patients with gastrointestinal stromal tumors.

  9. Risk of malignancy in thyroid incidentalomas detected by (18)f-fluorodeoxyglucose positron emission tomography

    DEFF Research Database (Denmark)

    Soelberg, Kerstin; Bonnema, Steen Joop; Brix, Thomas Heiberg

    2012-01-01

    Background: The expanding use of (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) has led to the identification of increasing numbers of patients with an incidentaloma in the thyroid gland. We aimed to review the proportion of incidental thyroid cancers found by (18)F-FDG PET...... or PET/computed tomography imaging. Methods: Studies evaluating thyroid carcinomas discovered incidentally in patients or healthy volunteers by (18)F-FDG PET were systematically searched in the PubMed database from 2000 to 2011. The main exclusion criteria were known thyroid disease, lack of assigned...... diagnoses, investigation of diffuse uptake only, or investigation of patients with head and neck cancer, or cancer in the upper part of the thorax. Results: Twenty-two studies met our criteria comprising a total of 125,754 subjects. Of these, 1994 (1.6%) had unexpected focal hypermetabolic activity, while...

  10. Single-photon emission computed tomography in human immunodeficiency virus encephalopathy: A preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    Masdeu, J.C.; Yudd, A.; Van Heertum, R.L.; Grundman, M.; Hriso, E.; O' Connell, R.A.; Luck, D.; Camli, U.; King, L.N. (St. Vincent' s Medical Center, New York, NY (USA))

    1991-08-01

    Depression or psychosis in a previously asymptomatic individual infected with the human immunodeficiency virus (HIV) may be psychogenic, related to brain involvement by the HIV or both. Although prognosis and treatment differ depending on etiology, computed tomography (CT) and magnetic resonance imaging (MRI) are usually unrevealing in early HIV encephalopathy and therefore cannot differentiate it from psychogenic conditions. Thirty of 32 patients (94%) with HIV encephalopathy had single-photon emission computed tomography (SPECT) findings that differed from the findings in 15 patients with non-HIV psychoses and 6 controls. SPECT showed multifocal cortical and subcortical areas of hypoperfusion. In 4 cases, cognitive improvement after 6-8 weeks of zidovudine (AZT) therapy was reflected in amelioration of SPECT findings. CT remained unchanged. SPECT may be a useful technique for the evaluation of HIV encephalopathy.

  11. Clinical Utility of Positron Emission Tomography Magnetic Resonance Imaging (PET-MRI) in Gastrointestinal Cancers.

    Science.gov (United States)

    Matthews, Robert; Choi, Minsig

    2016-09-09

    Anatomic imaging utilizing both CT (computed tomography) and MRI (magnetic resonance imaging) limits the assessment of cancer metastases in lymph nodes and distant organs while functional imaging like PET (positron emission tomography) scan has its limitation in spatial resolution capacity. Hybrid imaging utilizing PET-CT and PET-MRI are novel imaging modalities that are changing the current landscape in cancer diagnosis, staging, and treatment response. MRI has shown to have higher sensitivity in soft tissue, head and neck pathology, and pelvic disease, as well as, detecting small metastases in the liver and bone compared to CT. Combining MRI with PET allows for detection of metastases that may have been missed with current imaging modalities. In this review, we will examine the clinical utility of FDG PET-MRI in the diagnosis and staging of gastrointestinal cancers with focus on esophageal, stomach, colorectal, and pancreatic cancers. We will also explore its role in treatment response and future directions associated with it.

  12. Imaging prostate cancer: an update on positron emission tomography and magnetic resonance imaging

    DEFF Research Database (Denmark)

    Bouchelouche, Kirsten; Turkbey, Baris; Choyke, Peter;

    2010-01-01

    Prostate cancer is a common cancer in men and continues to be a major health problem. Imaging plays an essential role in the clinical management of patients. An important goal for prostate cancer imaging is more accurate disease characterization through the synthesis of anatomic, functional......, and molecular imaging information. Developments in imaging technologies, specifically magnetic resonance imaging (MRI) and positron emission tomography (PET)/computed tomography (CT), have improved the detection rate of prostate cancer. MRI has improved lesion detection and local staging. Furthermore, MRI...... allows functional assessment with techniques such as diffusion-weighted MRI, MR spectroscopy, and dynamic contrast-enhanced MRI. The most common PET radiotracer, (18)F-fluorodeoxyglucose, is not very useful in prostate cancer. However, in recent years other PET tracers have improved the accuracy of PET...

  13. DETECTION OF MYOCARDIAL VIABILITY IN ISСHAEMIC DAMAGE USING MAGNETIC RESONANCE AND EMISSION TOMOGRAPHY

    Directory of Open Access Journals (Sweden)

    V. Yu. Ussov

    2013-01-01

    Full Text Available A review of modern methods of magnetic resonance imaging (MRI and emission tomography (singlephoton emission and positron emission computer tomography – SPECT and PET as toos for diagnosis and prognosis of myocardial ischaemic damage, in particular in coronary revascularization. The definition of term “myocardial viability” is discussed. It has been shown that the integrity of blood-tissue barrier between myocardium and microcirculatory vessels is the most sensitive marker of tissue viability and of functional integrity of myocardium. It’s evaluation by means of contrast-enhanced MRI of myocardium is the most available and most precise technique of diagnosis and prognosis both in patients with postinfarction myocardiosclerosis and in patients with coronary disease without myocardial infarction. It is proposed that in the nearest future the combination of MR-coronarography and contrast-enhanced MRI of myocardium will provide a possibility to obtain the full set of data necessary for planning of endovascular and surgical treatment of various forms of coronary heart disease. PET and SPECT techniques currently are of some essential interest for pathophysiologic research of coronary ishaemia in clinical and experimental studies as well as for qualitative visual studies of pharmacokinetics.

  14. 2-deoxy-2-(18F)fluoro-D-glucose positron emission tomography/computed tomography imaging in paediatric oncology

    Institute of Scientific and Technical Information of China (English)

    John; Freebody; Eva; A; Wegner; Monica; A; Rossleigh

    2014-01-01

    Positron emission tomography(PET) is a minimally in-vasive technique which has been well validated for the diagnosis, staging, monitoring of response to therapy, and disease surveillance of adult oncology patients. Tra-ditionally the value of PET and PET/computed tomogra-phy(CT) hybrid imaging has been less clearly defined for paediatric oncology. However recent evidence has emerged regarding the diagnostic utility of these mo-dalities, and they are becoming increasingly important tools in the evaluation and monitoring of children with known or suspected malignant disease. Important indi-cations for 2-deoxy-2-(18F)fluoro-D-glucose(FDG) PET in paediatric oncology include lymphoma, brain tumours, sarcoma, neuroblastoma, Langerhans cell histiocytosis, urogenital tumours and neurofibromatosis type Ⅰ. This article aims to review current evidence for the use of FDG PET and PET/CT in these indications. Attention will also be given to technical and logistical issues, the description of common imaging pitfalls, and dosimetric concerns as they relate to paediatric oncology.

  15. [Study of regional cerebral glucose metabolism, in man, while awake or asleep, by positron emission tomography].

    Science.gov (United States)

    Franck, G; Salmon, E; Poirrier, R; Sadzot, B; Franco, G

    1987-03-01

    Measurements of regional cerebral glucose uptake by the 18F-fluorodeoxyglucose technique (18FDG) and positron emission tomography (PET) along with polygraph recordings were made serially during relaxed wakefulness and different stages of nocturnal sleep in two right-handed normal volunteers. During stage III-IV sleep, values declined diffusely in both hemispheric regions (-31%), thalamus (-33%), cerebellum (-33%) and brain stem (-25%). During paradoxical sleep regional values increased diffusely compared with slow wave sleep. Compared to wakefulness, regional metabolic values seemed to increase but the results were more variable from one volunteer to the other. These preliminary data indicate important regional alterations in cerebral metabolism between sleep states.

  16. Radiolabeled phosphonium salts as mitocondrial voltage sensors for positron emission tomography myocardial imaging agents

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Yon; Min, Jung Joon [Dept. of Nuclear Medicine,Chonnam National University Medical School and Hwasun Hospital, Gwangju (Korea, Republic of)

    2016-09-15

    Despite substantial advances in the diagnosis of cardiovascular disease, {sup 18}F-labeled positron emission tomography (PET) radiopharmaceuticals remain necessary to diagnose heart disease because clinical use of current PET tracers is limited by their short half-life. Lipophilic cations such as phosphonium salts penetrate the mitochondrial membranes and accumulate in mitochondria of cardiomyocytes in response to negative inner-transmembrane potentials. Radiolabeled tetraphenyl phosphonium cation derivatives have been developed as myocardial imaging agents for PET. In this review, a general overview of these radiotracers, including their radiosynthesis, in vivo characterization, and evaluation is provided and clinical perspectives are discussed.

  17. Distributed Microprocessor Automation Network for Synthesizing Radiotracers Used in Positron Emission Tomography [PET

    Science.gov (United States)

    Russell, J. A. G.; Alexoff, D. L.; Wolf, A. P.

    1984-09-01

    This presentation describes an evolving distributed microprocessor network for automating the routine production synthesis of radiotracers used in Positron Emission Tomography. We first present a brief overview of the PET method for measuring biological function, and then outline the general procedure for producing a radiotracer. The paper identifies several reasons for our automating the syntheses of these compounds. There is a description of the distributed microprocessor network architecture chosen and the rationale for that choice. Finally, we speculate about how this network may be exploited to extend the power of the PET method from the large university or National Laboratory to the biomedical research and clinical community at large. (DT)

  18. A positron emission tomography study of wind-up pain in chronic postherniotomy pain

    DEFF Research Database (Denmark)

    Kupers, Ron; Lonsdale, Markus Georg; Aasvang, Eske Kvanner;

    2011-01-01

    -induced wind-up pain in neuropathic pain patients. We therefore used positron emission tomography (PET) to investigate the cerebral response pattern of mechanical wind-up pain in a homogenous group of 10 neuropathic pain patients with long-standing postherniotomy pain in the groin area. Patients were scanned......) and the brain stem. A direct comparison between wind-up pain and pressure pain revealed that both activated a largely overlapping network. Since no de novo brain areas were activated by wind-up pain, our data suggest that the processes specific to wind-up pain do not occur at the cerebral level....

  19. Amyloid and metabolic positron emission tomography imaging of cognitively normal adults with Alzheimer's parents

    DEFF Research Database (Denmark)

    Mosconi, Lisa; Rinne, Juha O; Tsui, Wai H

    2013-01-01

    emission tomography (PET) with (11)C-Pittsburgh compound B (PiB) and 18F-fluoro-2-deoxy-d-glucose (FDG). These included 19 NL with a maternal history (MH), 12 NL with a paternal history (PH), and 16 NL with negative family history of AD (NH). Automated regions of interest, statistical parametric mapping......, voxel-wise intermodality correlations, and logistic regressions were used to examine cerebral-to-cerebellar PiB and FDG standardized uptake value ratios across groups. The MH group showed higher PiB retention and lower metabolism in AD regions compared with NH and PH, which were negatively correlated...

  20. Synthesis of analogues of (-)-cytisine for in vivo studies of nicotinic receptors using positron emission tomography.

    Science.gov (United States)

    Marrière, E; Rouden, J; Tadino, V; Lasne, M C

    2000-04-20

    [formula: see text] 9-Substituted analogues of (-)-cytisine were synthesized in high yields via palladium-mediated couplings of either 9-(-)-bromocytisine and organostannanes or 9-(-)-trimethylstannylcytisine and fluorobromobenzene. The protection of the amine with a nitroso group and the use of PdCl2(PPh3)2 to carry out the Stille reaction allowed the rapid synthesis of 9-(4'-[18F]fluorophenyl)cytisine (18F: t1/2 = 109.7 min), a new promising radioligand (radiochemical yield: 10% from [18F]KF, 150 min, four steps) for positron emission tomography studies of alpha 4 beta 2 nicotinic receptors.

  1. Fluorodeoxyglucose positron emission tomography (FDG-PET) for monitoring lymphadenopathy in the autoimmune lymphoproliferative syndrome (ALPS).

    Science.gov (United States)

    Rao, V Koneti; Carrasquillo, Jorge A; Dale, Janet K; Bacharach, Stephen L; Whatley, Millie; Dugan, Faith; Tretler, Jean; Fleisher, Thomas; Puck, Jennifer M; Wilson, Wyndham; Jaffe, Elaine S; Avila, Nilo; Chen, Clara C; Straus, Stephen E

    2006-02-01

    Autoimmune lymphoproliferative syndrome (ALPS) is associated with mutations that impair the activity of lymphocyte apoptosis proteins, leading to chronic lymphadenopathy, hepatosplenomegaly, autoimmunity, and an increased risk of lymphoma. We investigated the utility of fluorodeoxyglucose positron emission tomography (FDG-PET) in discriminating benign from malignant lymphadenopathy in ALPS. We report that FDG avidity of benign lymph nodes in ALPS can be high and, hence, by itself does not imply presence of lymphoma; but FDG-PET can help guide the decision for selecting which of many enlarged nodes in ALPS patients to biopsy when lymphoma is suspected.

  2. Left ventricular volume determination from single-photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Bunker, S.R.; Hartshorne, M.F.; Schmidt, W.P.; Cawthon, M.A.; Karl, R.D. Jr.; Bauman, J.M.; Howard, W.H. III; Rubal, B.J.

    1985-02-01

    To compare the accuracy of single-photon emission computed tomography (SPECT) with that of contrast cineangiography in measuring left ventricular end-diastolic volume, 25 consecutive patients undergoing catheterizaiton for coronary artery or valvular heart disease were first evaluated scintigraphically. SPECT volume values showed a high degree of correlation with those determined by angiography with a standard error of the estimate of 23 ml. SPECT offers a highly accurate and essentially noninvasive method for measuring chamber volumes that is independent of geometric assumptions about ventricular configuration and chest wall attenuation and does not require blood sample counting.

  3. Painful spondylolysis or spondylolisthesis studied by radiography and single-photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Collier, B.D.; Johnson, R.P.; Carrera, G.F.; Meyer, G.A.; Schwab, J.P.; Flatley, T.J.; Isitman, A.T.; Hellman, R.S.; Zielonka, J.S.; Knobel, J.

    1985-01-01

    Planar bone scintigraphy (PBS) and single-photon emission computed tomography (SPECT) were compared in 19 adults with radiographic evidence of spondylolysis and/or spondylolisthesis. SPECT was more sensitive than PBS when used to identify symptomatic patients and sites of painful defects in the pars interarticularis. In addition, SPECT allowed more accurate localization than PBS. In 6 patients, spondylolysis or spondylolisthesis was unrealted to low back pain, and SPECT images of the posterior neural arch were normal. The authors conclude that when spondylolysis or spondylolisthesis is the cause of low back pain, pars defects are frequently heralded by increased scintigraphic activity which is best detected and localized by SPECT.

  4. Single photon image from position emission tomography with insertable collimator for boron neutron capture therapy

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Joo Young; Yoo, Do Kun; Suh, Tae Suk [Dept. of Biomedical Engineering and Research Institute of Biomedical Engineering, College of Medicine, Catholic University of Korea, Seoul (Korea, Republic of); Hong, Key Jo [Molecular Imaging Program at Stanford (MIPS), Dept. of Radiology, Stanford University, Stanford (United States)

    2014-04-15

    The aim of our proposed system is to confirm the feasibility of extraction of two types of images from one positron emission tomography (PET) module with an insertable collimator for brain tumor treatment during the boron neutron capture therapy (BNCT). The BNCT theory and conceptual diagram of our proposed system are shown fig.1. Data from the PET module, neutron source, and collimator was entered in the Monte Carlon-particle extende source code. We attempted to acquire the PET and SPECT images simultaneously using only PET without an additional isotope. Single photon images were acquired using an insertable collimator on a PET detector.

  5. Positron emission tomography in the diagnosis and staging of lung cancer

    DEFF Research Database (Denmark)

    Fischer, B M; Mortensen, J; Højgaard, L

    2001-01-01

    positron emission tomography (PET) and gamma-camera PET in the diagnostic investigation of non-small-cell lung cancer (NSCLC). A systematic literature search was carried out in the MEDLINE and EMBASE databases and the Cochrane Controlled Trials Register. We identified 55 original works on the diagnostic......Lung cancer is the cause of 32% of all male cancer deaths and 25% of all female cancer deaths. Because the prognosis depends on early diagnosis and staging, continuous evaluation of the diagnostic tools available is important. The aim of this study was to assess the diagnostic value of dedicated...

  6. New Cyclotron Targetry to Enhance F-18 clinical Position Emission Tomography

    Energy Technology Data Exchange (ETDEWEB)

    J. Michael Doster

    2008-12-19

    This project proposes to develop cyclotron targets that produce F-18 for clinical Positron Emission Tomography (PET) at significantly higher rates than that available from current targetry. This production rate of 18F is directly proportional to the beam current. Higher beam currents would result in increased 18F production but would be accompanied by higher heat loads to the target. The beam power available in most commercial cyclotrons exceeds the heat removal capacity of current target technology by a factor of two to four, significantly limiting the production rate of Fluorine-18.

  7. Noninvasive xenon-133 measurements of cerebral blood flow using stationary detectors compared with dynamic emission tomography

    DEFF Research Database (Denmark)

    Schroeder, T; Vorstrup, S; Lassen, N A;

    1986-01-01

    Repeated bedside measurements of CBF have been made possible by the recent development of a mobile unit with 10 stationary detectors using the intravenous xenon-133 method. To evaluate this technique, comparative CBF studies at rest and following the application of a cerebral vasodilatory stimulus...... (acetazolamide, 1 g i.v.) were performed with the mobile equipment and with xenon-133 single-photon emission inhalation tomography in patients with cerebrovascular disease. The CBF level and the flow response to acetazolamide as determined with the two methods were well correlated, although at low flow levels...

  8. Neuro-imaging and positron emission tomography of congenital homonymous hemianopsia.

    Science.gov (United States)

    Bosley, T M; Kiyosawa, M; Moster, M; Harbour, R; Zimmerman, R; Savino, P J; Sergott, R C; Alavi, A; Reivich, M

    1991-04-15

    Congenital homonymous hemianopsia is an uncommon asymptomatic visual field defect discovered typically in young adult life that is caused by a diverse group of insults to the retrochiasmal afferent visual system occurring prenatally, at birth, or during early childhood. We treated eight patients with congenital homonymous hemianopsia; seven with damage involving the optic radiations and one with an abnormality of the optic tract. We performed positron emission tomography using 18F-fluoro-2-deoxyglucose on two patients with dense homonymous hemianopsias, lesions of the contralateral optic radiations, and largely intact occipital cortex. These studies showed minimal abnormalities in resting visual cortex glucose metabolism of the affected visual cortex.

  9. Clinical correlates of decreased anteroposterior metabolic gradients in positron emission tomography (PET) of schizophrenic patients

    Energy Technology Data Exchange (ETDEWEB)

    DeLisi, L.E.; Buchsbaum, M.S.; Holcomb, H.H.; Dowling-Zimmerman, S.; Pickar, D.; Boronow, J.; Morihisa, J.M.; van Kammen, D.P.; Carpenter, W.; Kessler, R.

    1985-01-01

    The finding in schizophrenic patients of a reversal of the normal frontal to posterior pattern of brain metabolic activity with positron emission tomography (PET) is of interest, but its relevance to psychopathology is unknown. Using PET, the authors studied 21 patients with chronic schizophrenia and 21 age- and sex-matched control subjects. Although eight of the 21 patients and only one of the control subjects showed a relatively lower anteroposterior metabolic gradient, no clinical correlates of this finding were noted. In addition, cerebral atrophy, as determined by CAT scan, was not associated with this aberrant metabolic pattern.

  10. Feasibility of Computed Tomography-Guided Methods for Spatial Normalization of Dopamine Transporter Positron Emission Tomography Image.

    Directory of Open Access Journals (Sweden)

    Jin Su Kim

    Full Text Available Spatial normalization is a prerequisite step for analyzing positron emission tomography (PET images both by using volume-of-interest (VOI template and voxel-based analysis. Magnetic resonance (MR or ligand-specific PET templates are currently used for spatial normalization of PET images. We used computed tomography (CT images acquired with PET/CT scanner for the spatial normalization for [18F]-N-3-fluoropropyl-2-betacarboxymethoxy-3-beta-(4-iodophenyl nortropane (FP-CIT PET images and compared target-to-cerebellar standardized uptake value ratio (SUVR values with those obtained from MR- or PET-guided spatial normalization method in healthy controls and patients with Parkinson's disease (PD.We included 71 healthy controls and 56 patients with PD who underwent [18F]-FP-CIT PET scans with a PET/CT scanner and T1-weighted MR scans. Spatial normalization of MR images was done with a conventional spatial normalization tool (cvMR and with DARTEL toolbox (dtMR in statistical parametric mapping software. The CT images were modified in two ways, skull-stripping (ssCT and intensity transformation (itCT. We normalized PET images with cvMR-, dtMR-, ssCT-, itCT-, and PET-guided methods by using specific templates for each modality and measured striatal SUVR with a VOI template. The SUVR values measured with FreeSurfer-generated VOIs (FSVOI overlaid on original PET images were also used as a gold standard for comparison.The SUVR values derived from all four structure-guided spatial normalization methods were highly correlated with those measured with FSVOI (P < 0.0001. Putaminal SUVR values were highly effective for discriminating PD patients from controls. However, the PET-guided method excessively overestimated striatal SUVR values in the PD patients by more than 30% in caudate and putamen, and thereby spoiled the linearity between the striatal SUVR values in all subjects and showed lower disease discrimination ability. Two CT-guided methods showed

  11. The role of positron emission tomography/computed tomography in radiation therapy planning for patients with lung cancer.

    Science.gov (United States)

    Mac Manus, Michael P; Hicks, Rodney J

    2012-09-01

    Positron emission tomography (PET)/computed tomography (CT) has rapidly assumed a critical role in the management of patients with locoregionally advanced lung cancers who are candidates for definitive radiation therapy (RT). Definitive RT is given with curative intent, but can only be successful in patients without distant metastasis and if all gross tumor is contained within the treated volume. An increasing body of evidence supports the use of PET-based imaging for selection of patients for both surgery and definitive RT. Similarly, the use of PET/CT images for accurate target volume definition in lung cancer is a dynamic area of research. Most available evidence on PET staging of lung cancer relates to non-small cell lung cancer (NSCLC). In general clinical use, (18)F-fluorodeoxyglucose (FDG) is the primary radiopharmaceutical useful in NSCLC. Other tracers, including proliferation markers and hypoxia tracers, may have significant roles in future. Much of the FDG-PET literature describing the impact of PET on actual patient management has concerned candidates for surgical resection. In the few prospective studies where PET was used for staging and patient selection in NSCLC candidates for definitive RT, 25%-30% of patients were denied definitive RT, generally because PET detected unsuspected advanced locoregional or distant metastatic disease. PET/CT and CT findings are often discordant in NSCLC but studies with clinical-pathological correlation always show that PET-assisted staging is more accurate than conventional assessment. In all studies in which "PET-defined" and "non-PET-defined" RT target volumes were compared, there were major differences between PET and non-PET volumes. Therefore, in cases where PET-assisted and non-PET staging are different and biopsy confirmation is unavailable, it is rational to use the most accurate modality (namely PET/CT) to define the target volume. The use of PET/CT in patient selection and target volume definition is likely

  12. Pretreatment Staging Positron Emission Tomography/Computed Tomography in Patients With Inflammatory Breast Cancer Influences Radiation Treatment Field Designs

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Gary V. [Department of Radiation Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Niikura, Naoki [Department of Breast and Endocrine Surgery, Tokai University School of Medicine, Kanagawa (Japan); Yang Wei [Department of Diagnostic Radiology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Rohren, Eric [Department of Nuclear Medicine, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Valero, Vicente [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Woodward, Wendy A. [Department of Radiation Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Alvarez, Ricardo H. [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Lucci, Anthony [Department of Surgical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Ueno, Naoto T. [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Buchholz, Thomas A., E-mail: tbuchhol@mdanderson.org [Department of Radiation Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2012-08-01

    Purpose: Positron emission tomography/computed tomography (PET/CT) is increasingly being utilized for staging of inflammatory breast cancer (IBC). The purpose of this study was to define how pretreatment PET/CT studies affected postmastectomy radiation treatment (PMRT) planning decisions for IBC. Methods and Materials: We performed a retrospective analysis of 62 patients diagnosed with IBC between 2004 and 2009, who were treated with PMRT in our institution and who had a staging PET/CT within 3 months of diagnosis. Patients received a baseline physical examination, staging mammography, ultrasonographic examination of breast and draining lymphatics, and chest radiography; most patients also had a bone scan (55 patients), liver imaging (52 patients), breast MRI (46 patients), and chest CT (25 patients). We compared how PET/CT findings affected PMRT, assuming that standard PMRT would target the chest wall, level III axilla, supraclavicular fossa, and internal mammary chain (IMC). Any modification of target volumes, field borders, or dose prescriptions was considered a change. Results: PET/CT detected new areas of disease in 27 of the 62 patients (44%). The areas of additional disease included the breast (1 patient), ipsilateral axilla (1 patient), ipsilateral supraclavicular (4 patients), ipsilateral infraclavicular (1 patient), ipsilateral IMC (5 patients), ipsilateral subpectoral (3 patients), mediastinal (8 patients), other distant/contralateral lymph nodes (15 patients), or bone (6 patients). One patient was found to have a non-breast second primary tumor. The findings of the PET/CT led to changes in PMRT in 11 of 62 patients (17.7%). These changes included additional fields in 5 patients, adjustment of fields in 2 patients, and higher doses to the supraclavicular fossa (2 patients) and IMC (5 patients). Conclusions: For patients with newly diagnosed IBC, pretreatment PET/CT provides important information concerning involvement of locoregional lymph nodes

  13. [18F]Fluorodeoxyglucose-positron emission tomography screening for lung cancer: a systematic review and meta-analysis

    OpenAIRE

    Chien, Chun-Ru; Liang, Ji-An; Chen, Jin-Hua; Wang, Hsiao-Nin; Lin, Cheng-Chieh; Chen, Chih-Yi; Wang, Pin-Hui; Kao, Chia-Hung; Yeh, Jun-Jun

    2013-01-01

    Abstract Rationale and objectives: Although low-dose computed tomography (CT) is a recommended modality for lung cancer screening in high-risk populations, the role of other modalities, such as [18F]fluorodeoxyglucose-positron emission tomography (PET), is unclear. We conducted a systematic review to describe the role of PET in lung cancer screening. Materials and methods: A systematic review was conducted by reviewing primary studies focusing on PET screening for lung cancer until July 2012....

  14. Application of Positron Emission Tomography to Aerosol Transport Research in a Model of Human Lungs

    Directory of Open Access Journals (Sweden)

    Jicha M.

    2013-04-01

    Full Text Available Positron Emission Tomography (PET is a convenient method for measurement of aerosol deposition in complex models of lungs. It allows not only the evaluation of regional deposition characteristics but also precisely detects deposition hot spots. The method is based on a detection of a pair of annihilation photons moving in opposite directions as a result of positron – electron interaction after the positron emission decay of a suitable radioisotope. Liquid di(2-ethylhexyl sebacate (DEHS particles tagged with fluorine-18 as a radioactive tracer were generated by condensation monodisperse aerosol generator. Aerosol deposition was measured for three different inhalation flowrates and for two sizes of particles. Combination of PET with Computed Tomography (CT in one device allowed precise localisation of particular segments of the model. The results proved correlation of deposition efficiency with Stokes number, which means that the main deposition mechanism is inertial impaction. As a next task the methodology for tagging the solid aerosol particles with radioactive tracer will be developed and deposition of porous and fiber aerosols will be measured.

  15. Statistical parametric mapping in brain single photon computed emission tomography after carbon monoxide intoxication.

    Science.gov (United States)

    Watanabe, N; Nohara, S; Matsuda, H; Sumiya, H; Noguchi, K; Shimizu, M; Tsuji, S; Kinuya, S; Shuke, N; Yokoyama, K; Seto, H

    2002-04-01

    The purpose of this retrospective study was to assess regional cerebral blood flow in patients after carbon monoxide intoxication by using brain single photon emission computed tomography and statistical parametric mapping. Eight patients with delayed neuropsychiatric sequelae and ten patients with no neuropsychiatric symptoms after carbon monoxide intoxication were studied with brain single photon emission tomography imaging with 99mTc-hexamethyl-propyleneamine oxime. Forty-four control subjects were also studied. We used the adjusted regional cerebral blood flow images in relative flow distribution (normalization of global cerebral blood flow for each subject to 50 ml x 100 g(-1) x min(-1) with proportional scaling) to compare these groups with statistical parametric mapping. Using this technique, significantly decreased regional cerebral blood flow was noted extensively in the bilateral frontal lobes as well as the bilateral insula and a part of the right temporal lobe in the patients with delayed neuropsychiatric sequelae as compared with normal volunteers (Pparametric mapping is a useful technique for highlighting differences in regional cerebral blood flow in patients following carbon monoxide intoxication as compared with normal volunteers. The selectively reduced blood flow noted in this investigation supports the contention that the decrease following carbon monoxide intoxication may be prolonged and further worsen in the frontal lobe. In addition, the present study may help to clarify the characteristics of the pathophysiological alteration underlying delayed neuropsychiatric sequelae.

  16. Geneva University - The AX-PET experiment : A demonstrator for an axial Positron Emission Tomography

    CERN Multimedia

    Université de Genève

    2012-01-01

    Geneva University École de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 Genève 4 Tél.: (022) 379 62 73 Fax: (022) 379 69 92   Wednesday 14 March 2012 SEMINAIRE DE PHYSIQUE CORPUSCULAIRE 11.15 a.m. - Science II, Auditoire 1S081, 30, quai Ernest-Ansermet, 1211 Genève 4 The AX-PET experiment : A demonstrator for an axial Positron Emission Tomography Dr Chiara CASELLA   ETH Zurich   PET (Positron Emission Tomography) is a tool for in-vivo functional imaging, successfully used since the earliest days of nuclear medicine. It is based on the detection of the two coincident 511 keV photons from the annihilation of a positron, emitted from a radiotracer injected into the body. Tomographic analysis of the coincidence data allows for a 3D reconstructed image of the source distribution. The AX-PET experiment proposes a novel geometrical approach for a PET scanner, in which l...

  17. DE-BLURRING SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY IMAGES USING WAVELET DECOMPOSITION

    Directory of Open Access Journals (Sweden)

    Neethu M. Sasi

    2016-02-01

    Full Text Available Single photon emission computed tomography imaging is a popular nuclear medicine imaging technique which generates images by detecting radiations emitted by radioactive isotopes injected in the human body. Scattering of these emitted radiations introduces blur in this type of images. This paper proposes an image processing technique to enhance cardiac single photon emission computed tomography images by reducing the blur in the image. The algorithm works in two main stages. In the first stage a maximum likelihood estimate of the point spread function and the true image is obtained. In the second stage Lucy Richardson algorithm is applied on the selected wavelet coefficients of the true image estimate. The significant contribution of this paper is that processing of images is done in the wavelet domain. Pre-filtering is also done as a sub stage to avoid unwanted ringing effects. Real cardiac images are used for the quantitative and qualitative evaluations of the algorithm. Blur metric, peak signal to noise ratio and Tenengrad criterion are used as quantitative measures. Comparison against other existing de-blurring algorithms is also done. The simulation results indicate that the proposed method effectively reduces blur present in the image.

  18. Methods and clinical applications of positron emission tomography in endocrinology. Methodologie et applications cliniques en endocrinologie de la tomographie a emission de positons

    Energy Technology Data Exchange (ETDEWEB)

    Landsheere, C. de; Lamotte, D. (Liege Univ. (BE))

    1990-01-01

    Positron emission tomography (PET) allows to detect in coincidence photons issued from annihilation between positrons and electrons nearby situated. Tomographic detection (plane by plane) and tomographic reconstruction will lead to the quantitation of radioactive distribution per voxel, in the organ of interest. Recent tomographs can acquire simultaneously several transaxial slices, with a high sensitivity and a spatial resolution of 3-5 mm. Commonly used positron emitters have a short half-life: 2, 10, 20 and 110 min for {sup 15}0, {sup 13}N, {sup 11}C and {sup 18}F, respectively. The use of these isotopes requires on line production of radionuclides and synthesis of selected molecules. In endocrinology, PET allows among others to study noninvasively the receptor density of hormonodependent neoplasms such as breast, uterus, prostate tumors and prolactinomas. These last tumors represent a particular entity because of several combined characteristics: high turnover rate of amino acids, high density of dopaminergic receptors and response to bromocriptine (analogue of dopamine inhibiting the secretion of prolactine) in relation to the level of receptors. Because PET permits to evaluate the density of dopaminergic receptors and the metabolism of amino acids, theoretical response of the prolactinoma to bromocriptin can be predicted, the achieved therapeutic efficacy can be estimated and the long-term follow up of tumor growth can be assessed. This example illustrates the clinical value of PET in endocrinology.

  19. Evaluation of external beam hardening filters on image quality of computed tomography and single photon emission computed tomography/computed tomography.

    Science.gov (United States)

    Rana, Nivedita; Rawat, Dinesh; Parmar, Madan; Dhawan, Devinder Kumar; Bhati, Ashok Kumar; Mittal, Bhagwant Rai

    2015-01-01

    This study was undertaken to evaluate the effect of external metal filters on the image quality of computed tomography (CT) and single photon emission computed tomography (SPECT)/CT images. Images of Jaszack phantom filled with water and containing iodine contrast filled syringes were acquired using CT (120 kV, 2.5 mA) component of SPECT/CT system, ensuring fixation of filter on X-ray collimator. Different thickness of filters of Al and Cu (1 mm, 2 mm, 3 mm, and 4 mm) and filter combinations Cu 1 mm, Cu 2 mm, Cu 3 mm each in combination with Al (1 mm, 2 mm, 3 mm, and 4 mm), respectively, were used. All image sets were visually analyzed for streak artifacts and contrast to noise ratio (CNR) was derived. Similar acquisition was done using Philips CT quality control (QC) phantom and CNR were calculated for its lexan, perspex, and teflon inserts. Attenuation corrected SPECT/CT images of Jaszack phantom filled with 444-555 MBq (12-15 mCi) of (99m)Tc were obtained by applying attenuation correction map generated by hardened X-ray beam for different filter combination, on SPECT data. Uniformity, root mean square (rms) and contrast were calculated in all image sets. Less streak artifacts at iodine water interface were observed in images acquired using external filters as compared to those without a filter. CNR for syringes, spheres, and inserts of Philips CT QC phantom was almost similar to Al 2 mm, Al 3 mm, and without the use of filters. CNR decreased with increasing copper thickness and other filter combinations. Uniformity and rms were lower, and value of contrast was higher for SPECT/CT images when CT was acquired with Al 2 mm and 3 mm filter than for images acquired without a filter. The study suggests that for Infinia Hawkeye 4, SPECT/CT system, Al 2 mm, and 3 mm are the optimum filters for improving image quality of SPECT/CT images of Jaszack or Philips CT QC phantom keeping other parameters of CT constant.

  20. Prospective, blinded trial of whole-body magnetic resonance imaging versus computed tomography positron emission tomography in staging primary and recurrent cancer of the head and neck.

    LENUS (Irish Health Repository)

    O'Neill, J P

    2012-02-01

    OBJECTIVES: To compare the use of computed tomography - positron emission tomography and whole-body magnetic resonance imaging for the staging of head and neck cancer. PATIENTS AND METHODS: From January to July 2009, 15 consecutive head and neck cancer patients (11 men and four women; mean age 59 years; age range 19 to 81 years) underwent computed tomography - positron emission tomography and whole-body magnetic resonance imaging for pre-therapeutic evaluation. All scans were staged, as per the American Joint Committee on Cancer tumour-node-metastasis classification, by two blinded consultant radiologists, in two sittings. Diagnoses were confirmed by histopathological examination of endoscopic biopsies, and in some cases whole surgical specimens. RESULTS: Tumour staging showed a 74 per cent concordance, node staging an 80 per cent concordance and metastasis staging a 100 per cent concordance, comparing the two imaging modalities. CONCLUSION: This study found radiological staging discordance between the two imaging modalities. Whole-body magnetic resonance imaging is an emerging staging modality with superior visualisation of metastatic disease, which does not require exposure to ionising radiation.

  1. Fluorodeoxyglucose-positron emission tomography in carcinoma nasopharynx: Can we predict outcomes and tailor therapy based on postradiotherapy fluorodeoxyglucose-positron emission tomography?

    Directory of Open Access Journals (Sweden)

    Sarbani Ghosh Laskar

    2016-01-01

    Full Text Available Background: Positron emission tomography-computed tomography (PET-CT is an emerging modality for staging and response evaluation in carcinoma nasopharynx. This study was conducted to evaluate the impact of PET-CT in assessing response and outcomes in carcinoma nasopharynx. Materials and Methods: Forty-five patients of nonmetastatic carcinoma nasopharynx who underwent PET-CT for response evaluation at 10-12 weeks posttherapy between 2004 and 2009 were evaluated. Patients were classified as responders (Group A if there was a complete response on PET-CT or as nonresponders (Group B if there was any uptake above the background activity. Data regarding demographics, treatment, and outcomes were collected from their records and compared across the Groups A and B. Results: The median age was 41 years. 42 out of 45 (93.3% patients had WHO Grade 2B disease (undifferentiated squamous carcinoma. 24.4%, 31.1%, 15.6, and 28.8% patients were in American Joint Committee on Cancer Stage IIb, III, Iva, and IVb. All patients were treated with neoadjuvant chemotherapy followed by concomitant chemoradiotherapy. Forty-five patients, 28 (62.2% were classified as responders, whereas 17 (37.8% were classified as nonresponders. There was no significant difference in the age, sex, WHO grade, and stage distribution between the groups. Compliance to treatment was comparable across both groups. The median follow-up was 25.3 months (759 days. The disease-free survival (DFS of the group was 57.3% at 3 years. The DFS at 3 years was 87.3% and 19.7% for Group A and B, respectively (log-rank test, P < 0.001. Univariate and multivariate analysis revealed Groups to be the only significant factor predicting DFS (P value 0.002 and < 0.001, respectively. In Group B, the most common site of disease failure was distant (9, 53%. Conclusion: PET-CT can be used to evaluate response and as a tool to identify patients at higher risk of distant failure. Further, this could be exploited to

  2. Positron emission tomography/magnetic resonance hybrid scanner imaging of cerebral blood flow using 15O-water positron emission tomography and arterial spin labeling magnetic resonance imaging in newborn piglets

    DEFF Research Database (Denmark)

    Andersen, Julie B; Henning, William S; Lindberg, Ulrich;

    2015-01-01

    Abnormality in cerebral blood flow (CBF) distribution can lead to hypoxic-ischemic cerebral damage in newborn infants. The aim of the study was to investigate minimally invasive approaches to measure CBF by comparing simultaneous (15)O-water positron emission tomography (PET) and single TI pulsed...

  3. Development of radiotracers for imaging NR2B subtype NMDA receptors with positron emission tomography; Developpement de radiotraceurs pour la visualisation des recepteurs NMDA de sous-type NR2B par tomographie par emission de positons

    Energy Technology Data Exchange (ETDEWEB)

    Labas, R

    2007-07-01

    The aim of this thesis was to develop new radioactive tracers for imaging NR2B subtype NMDA receptors with positron emission tomography. Several compounds including 4-(4-fluoro-benzyl)piperidine and presenting interesting in vivo biological properties were the object of a labelling with a positrons emitter atom ({sup 11}C or {sup 18}F)

  4. Stimulated Emission Computed Tomography (NSECT) images enhancement using a linear filter in the frequency domain

    Energy Technology Data Exchange (ETDEWEB)

    Viana, Rodrigo S.S.; Tardelli, Tiago C.; Yoriyaz, Helio, E-mail: hyoriyaz@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Jackowski, Marcel P., E-mail: mjack@ime.usp.b [University of Sao Paulo (USP), SP (Brazil). Dept. of Computer Science

    2011-07-01

    In recent years, a new technique for in vivo spectrographic imaging of stable isotopes was presented as Neutron Stimulated Emission Computed Tomography (NSECT). In this technique, a fast neutrons beam stimulates stable nuclei in a sample, which emit characteristic gamma radiation. The photon energy is unique and is used to identify the emitting nuclei. The emitted gamma energy spectra can be used for reconstruction of the target tissue image and for determination of the tissue elemental composition. Due to the stochastic nature of photon emission process by irradiated tissue, one of the most suitable algorithms for tomographic reconstruction is the Expectation-Maximization (E-M) algorithm, once on its formulation are considered simultaneously the probabilities of photons emission and detection. However, a disadvantage of this algorithm is the introduction of noise in the reconstructed image as the number of iterations increases. This increase can be caused either by features of the algorithm itself or by the low sampling rate of projections used for tomographic reconstruction. In this work, a linear filter in the frequency domain was used in order to improve the quality of the reconstructed images. (author)

  5. Monte-Carlo simulations and image reconstruction for novel imaging scenarios in emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Gillam, John E. [The University of Sydney, Faculty of Health Sciences and The Brain and Mind Centre, Camperdown (Australia); Rafecas, Magdalena, E-mail: rafecas@imt.uni-luebeck.de [University of Lubeck, Institute of Medical Engineering, Ratzeburger Allee 160, 23538 Lübeck (Germany)

    2016-02-11

    Emission imaging incorporates both the development of dedicated devices for data acquisition as well as algorithms for recovering images from that data. Emission tomography is an indirect approach to imaging. The effect of device modification on the final image can be understood through both the way in which data are gathered, using simulation, and the way in which the image is formed from that data, or image reconstruction. When developing novel devices, systems and imaging tasks, accurate simulation and image reconstruction allow performance to be estimated, and in some cases optimized, using computational methods before or during the process of physical construction. However, there are a vast range of approaches, algorithms and pre-existing computational tools that can be exploited and the choices made will affect the accuracy of the in silico results and quality of the reconstructed images. On the one hand, should important physical effects be neglected in either the simulation or reconstruction steps, specific enhancements provided by novel devices may not be represented in the results. On the other hand, over-modeling of device characteristics in either step leads to large computational overheads that can confound timely results. Here, a range of simulation methodologies and toolkits are discussed, as well as reconstruction algorithms that may be employed in emission imaging. The relative advantages and disadvantages of a range of options are highlighted using specific examples from current research scenarios.

  6. Diagnostic accuracy of 18F-Fluorodeoxyglucose positron emission tomography in the follow-up of papillary or follicular thyroid cancer.

    NARCIS (Netherlands)

    Hooft, L.; Hoekstra, O.S.; Devillé, W.; Lips, W.; Teule, J.J.; Boers, M.; Tulder, M.W. van

    2001-01-01

    Positron emission tomography with 18F-fluorodeoxyglucose is a relatively new nuclear imaging technique in oncology. We conducted a systematic review to determine the diagnostic accuracy of 18F-fluorodeoxyglucose positron emission tomography in patients suspected of recurrent papillary or follicular

  7. In vivo evaluation of [11C]preladenant positron emission tomography for quantification of adenosine A2A receptors in the rat brain

    NARCIS (Netherlands)

    Zhou, Xiaoyun; Khanapur, Shivashankar; de Jong, Johan R; Willemsen, Antoon T.M.; Dierckx, Rudi Ajo; Elsinga, Philip H; de Vries, Erik Fj

    2016-01-01

    [(11)C]Preladenant was developed as a novel adenosine A2A receptor positron emission tomography radioligand. The present study aims to evaluate the suitability of [(11)C]preladenant positron emission tomography for the quantification of striatal A2A receptor density and the assessment of striatal A2

  8. Cerebral blood flow and metabolism for Broca's aphasia using positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Toshiaki

    1987-12-01

    A total of 11 patients with Broca's aphasia (BA) underwent positron emission tomography (PET) with the purpose of investigating the responsible region and the symptomatic flow and metabolism thresholds for BA. Computed tomography (CT) was concurrently performed. In the group of 3 patients undergoing PET with C-11 glucose, both PET and CT provided abnormal findings in the region that is thought to be responsible for BA (Broca's area), including the cortex and subcortex in the anterior region to Sylvian fissure. The Broca's area in the remaining one was shown as low C-11 accumulation area on PET and as isodensity on CT. The second group, consisting of 8 BA patients and 30 control patients without BA, underwent PET using O-15 steady method. PET showed reduction of regional cerebral blood flow (rCBF) and oxygen metabolic rate (rCMRO/sub 2/) in the Broca's area in all BA patients. Computed tomography showed abnormal low density in the Broca's area in 3 patients, and abnormal findings in the basal ganglionic region and subcortex without evidence for abnormal low density in the Broca's area in the other 5 patients. Comparison of rCBF and rCMRO/sub 2/ in BA patients with those in control patients may show the symptomatic thresholds to be 20 - 27 ml100 gmin for rCBF and 2.0 ml100 gmin for rCMRO/sub 2/. (Namekawa, K.).

  9. The Use of Positron Emission Tomography in Soft Tissue Sarcoma Patients under Therapy with Trabectedin

    Directory of Open Access Journals (Sweden)

    Gerlinde Egerer

    2009-07-01

    Full Text Available Background: We used 2-deoxy-2-[18F] fluoro-D-glucose (FDG positron emission tomography (PET to evaluate the FDG uptake in patients with advanced and/or metastatic soft tissue sarcoma (STS undergoing therapy with Ecteinascidin-743 (ET-743, Trabectedin, YondelisTM. Patients and Methods: The pilot study included nine patients with metastatic STS receiving a minimum of one cycle of treatment with trabectedin. Patients were examined using PET prior to onset of therapy and after completion of one or three cycles of trabectedin. Restaging according to Response Evaluation Criteria in Solid Tumours (RECIST was performed in parallel using computed tomography (CT and/or magnetic resonance imaging (MRI and served for reference. Results: Clinical outcome of nine evaluable patients was as follows: one patient with partial remission (PR, three patients with stable disease (SD, and five patients with progressive disease (PD. A more than 40% decrease of the standardized uptake value (SUV of sequential PET examination could be demonstrated for the responding patient (PR, whereas patients with SD or PD showed a stable SUV, but no increase in SUV. Conclusion: To our knowledge, this is the first small series of patients being treated with trabectedin and monitored using sequential PET imaging demonstrating SUV stabilization in nearly all monitored patients.

  10. The role of positron emission tomography in the detection of pancreatic disease

    Energy Technology Data Exchange (ETDEWEB)

    Syrota, A.; Duquesnoy, N.; Paraf, A.; Kellershohn, C.

    1982-04-01

    Positron emission tomography (PET) was used to assess possible pancreatic disease in 100 patients. Following injection of 10-15 mCi (370-740 MBq) of /sup 11/C-L-methionine, 4-12 transverse sections 2 cm thick were obtained. In 85 patients with a definite diagnosis (45 normal, 9 acute pancreatitis, 18 chronic pancreatitis, and 13 cancer), PET showed a sensitivity of 85.0%, a specificity of 97.8%, and an accuracy of 91.8%, higher than with transmission computed tomography (CT) or ultrasonography, despite relatively low spatial resolution; this can be explained by the fact that exocrine pancreatic function was altered prior to morphological change. In 22 normal subjects, 0.011 +/- 0.003% (mean +/- S.D.) of injected /sup 11/C was found in 1 ml of liver tissue and 0.015 +/- 0.005% in 1 ml of pancreatic tissue; the pancreas-to-liver concentration ratio was 1.3 +/- 0.4. Hepatic /sup 11/C concentration was identical in the four groups of patients. Pancreatic uptake of /sup 11/C-L-methionine was significantly lower in patients with chronic pancreatitis (n = 13) and pancreatic carcinoma (n = 10) (p <0.001); however, it was not possible to distinguish cancer from chronic pancreatitis because the same functional alteration occurred in both.

  11. The role of positron emission tomography in the detection of pancreatic disease

    Energy Technology Data Exchange (ETDEWEB)

    Syrota, A.; Duquesnoy, N.; Paraf, A.; Kellershohn, C.

    1982-04-01

    Positron emission tomography (PET) was used to assess possible pancreatic disease in 100 patients. Following injection of 10-15 mCi (370-740 MBq) of 11C-L-methionine, 4-12 transverse sections 2 cm thick were obtained. In 85 patients with a definite diagnosis (45 normal, 9 acute pancreatitis, 18 chronic pancreatitis, and 13 cancer), PET showed a sensitivity of 85.0%, a specificity of 97.8%, and an accuracy of 91.8%, higher than with transmission computed tomography (CT) or ultrasonography, despite relatively low spatial resolution; this can be explained by the fact that exocrine pancreatic function was altered prior to morphological change. In 22 normal subjects, 0.011 +/- 0.003% (mean +/- S.D). of injected 11C was found in 1 ml of liver tissue and 0.015 +/- 0.005% in 1 ml of pancreatic tissue; the pancreas-to-liver concentration ratio was 1.3 +/- 0.4. Hepatic 11C concentration was identical in the four groups of patients. Pancreatic uptake of 11C-L-methionine was significantly lower in patients with chronic pancreatitis (n . 13) and pancreatic carcinoma (n . 10) (p less than 0.001); however, it was not possible to distinguish cancer from chronic pancreatitis because the same functional alteration occurred in both.

  12. Application of 18F-fluorodeoxyglucose Positron Emission Tomography in Diagnosis of Malignant Diseases

    Institute of Scientific and Technical Information of China (English)

    Xiao-hong Ning; Qiu-li Meng; Yu-zhou Wang; Chun-mei Bai

    2009-01-01

    To testify the efficacy of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomo-graphy (PET) in the diagnosis of cancer.Methods A total of 170 patients with diagnosed cancer or suspicious cancer were enrolled in this study, and underwent 18F-FDG PET. The standard uptake value (SUV) and diameter for each abnormal region in PET images were analyzed. All data were analyzed by SPSS 11.5.Results PET scan identified a primary cancer in 45.8% (11/24) patients. The sensitivity and specificity of PET scan in differentiating malignant lesions from benign ones were 78.8% (52/66) and 77.1% (27/35) respectively. Twenty-nine out of 68 (42.6%) lesions were detected earlier by PET than by computed tomography. The SUV of primary cancer was significantly higher than that of metastatic lymph nodes (5.84±3.12 vs. 3.14±2.24, P<0.O01). And SUV of primary lung cancer was also significantly higher than that of metastatic lung cancer (6.30±3.01 vs. 2.86±2.37, P<0.01).Conclusion 18F-FDG PET plays a very important role in cancer diagnosis.

  13. 18F-fluorodeoxyglucose positron emission tomography might be useful for diagnosis of hepatic amyloidosis

    Directory of Open Access Journals (Sweden)

    Tawada A

    2014-06-01

    Full Text Available Akinobu Tawada,1 Tatsuo Kanda,1 Takashi Oide,2 Toshio Tsuyuguchi,1 Fumio Imazeki,1,3 Yukio Nakatani,2 Osamu Yokosuka11Department of Gastroenterology, 2Department of Diagnostic Pathology, Chiba University Hospital, Chuo-ku, Chiba, Japan; 3Safety and Health Organization, Chiba University, Inage-ku, Chiba, JapanAbstract: We report on a woman with hepatic involvement of primary systemic (immunoglobulin light chain, AL amyloidosis. Her diagnosis was confirmed by liver biopsy. Clinical symptoms of hepatic amyloidosis are generally mild at its first stage, with most frequent findings being hepatomegaly and alkaline phosphatase elevation. Recent advances in the understanding of the pathophysiology of systemic amyloidosis have made several treatments available. However, its prognosis is occasionally poor. Because liver biopsy is not always safe, other modalities for the diagnosis are needed. Of interest was that fluorodeoxyglucose (FDG uptake into the liver was observed, compared with that into the spleen, in this patient, indicating that FDG positron emission tomography and computed tomography might be useful for the diagnosis of hepatic amyloidosis with mild liver dysfunction.Keywords: amyloidosis, diagnosis, hepatic involvement, FDG PET

  14. Professional practice assessment. Pertinence of positron emission tomography clinical indications in oncology; Evaluation des pratiques professionnelles. Pertinence des indications de la tomographie a emission de positons en cancerologie

    Energy Technology Data Exchange (ETDEWEB)

    Le Stanc, E.; Tainturier, C. [Hopital Foch, Service de Medecine Nucleaire, 92 - Suresnes (France); Swaenepoel, J. [Hopital Foch, Cellule Qualite, 92 - Suresnes (France)

    2009-09-15

    Introduction As part of the health care quality and safety policy in France, Professional Practice Assessment (P.P.A.) are mandatory in the health services 'certification' process. We present our study regarding the pertinence of Positron Emission Tomography (PET) indications in oncology. Materials and methods A multidisciplinary task group used the Quick Audit method with two rounds of 100 request forms each. The assessment list of criteria comprised four items of decreasing relevance grading the PET scans clinical indications, which were derived from the three French published guidelines (S.O.R. [F.N.C.L.C.C]., 'Guide du bon usage des examens d'imagerie medicale' [S.F.R.-S.F.M.N.], 'Guide pour la redaction de protocoles pour la TEP au F.D.G. en cancerologie' [S.F.M.N.]) and five additional items: clinical information, patient's body weight, previous treatments dates, diabetes, claustrophobia. Results The first round showed that 68% of the requested scans corresponded to the two most relevant groups of indications (S.O.R. Standards and Options). The request forms were correctly filled in regarding the clinical information, but this was not the case for the other items we tested. Several actions were conducted: dedicated PET request form, availability of the S.O.R. on the hospital intranet, boost of the referring physicians awareness during the multidisciplinary oncology meetings (Reunions de Concertation Pluridisciplinaires RCP). The second round showed a better pertinence of the PET scans indications (75% versus 68%); the patient's body weight was more frequently mentioned on the request form. Discussion This study is an example of P.P.A. in our discipline. It led to an improvement of the oncologic PET scans clinical indications in our hospital. This work is pursued in everyday discussion with the referring clinicians, especially during the RCP. (authors)

  15. Refraction-compensated motion tracking of unrestrained small animals in positron emission tomography.

    Science.gov (United States)

    Kyme, Andre; Meikle, Steven; Baldock, Clive; Fulton, Roger

    2012-08-01

    Motion-compensated radiotracer imaging of fully conscious rodents represents an important paradigm shift for preclinical investigations. In such studies, if motion tracking is performed through a transparent enclosure containing the awake animal, light refraction at the interface will introduce errors in stereo pose estimation. We have performed a thorough investigation of how this impacts the accuracy of pose estimates and the resulting motion correction, and developed an efficient method to predict and correct for refraction-based error. The refraction model underlying this study was validated using a state-of-the-art motion tracking system. Refraction-based error was shown to be dependent on tracking marker size, working distance, and interface thickness and tilt. Correcting for refraction error improved the spatial resolution and quantitative accuracy of motion-corrected positron emission tomography images. Since the methods are general, they may also be useful in other contexts where data are corrupted by refraction effects.

  16. Single photon emission computerized tomography (SPECT) in detecting neurodegeneration in Huntington's disease.

    Science.gov (United States)

    Reynolds, N C; Hellman, R S; Tikofsky, R S; Prost, R W; Mark, L P; Elejalde, B R; Lebel, R; Hamsher, K S; Swanson, S; Benezra, E E

    2002-01-01

    Single photon emission computerized tomography (SPECT) studies were performed on 34 manifest Huntington's disease (HD) patients at various stages of clinical pathology ranging from early chorea to late dystonia with or without signs of dementia and 12 pre-symptomatic patients with abnormal terminal CAG expansions. Thirty HD patients with obvious clinical signs and seven pre-symptomatic patients without signs or symptoms of HD displayed selective caudate hypoperfusion by direct visual inspection. Such qualitative, selective striatal hypoperfusion patterns can be indicative of early and persistent metabolic changes in striatal neuropathology. SPECT studies can be useful in documenting early pre-clinical changes in patients with abnormal terminal CAG expansions and in confirming the presence of caudate pathology in patients with clinical signs of HD.

  17. Design And Development Of A Mammary And Axillary Region Positron Emission Tomography System (maxpet)

    CERN Document Server

    Doshi, N K

    2000-01-01

    Breast cancer is the second leading cause of cancer death in women. Currently, mammography and physical breast examination, both non-invasive techniques, provide the two most effective methods available for screening potential breast cancer patients. During the management of patients, however, several invasive techniques such as axillary lymph node dissection, core biopsies and lumpectomies, are utilized to determine the stage or malignancy of the disease with significant cost and morbidity associated with them. Positron Emission Tomography (PET), using [F-18] fluorodeoxyglucose (FDG) tracer is a sensitive and non-invasive imaging modality that may be a cost-effective alternative to certain invasive procedures. In this project we have developed a low cost, high performance, dedicated PET camera (maxPET) for mammary and axillary region imaging. The system consists of two 15x15 cm2 planar scintillation detector arrays composed of modular detectors operating in coincidence. The modular detectors are comprised of...

  18. High power laser production of short-lived isotopes for positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Ledingham, K W D [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); McKenna, P [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); McCanny, T [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Shimizu, S [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Yang, J M [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Robson, L [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Zweit, J [CR-UK/UMIST Radiochemical Targeting and Imaging, Paterson Institute for Cancer Research, Christie Hospital, Manchester M20 4BX (United Kingdom); Gillies, J M [CR-UK/UMIST Radiochemical Targeting and Imaging, Paterson Institute for Cancer Research, Christie Hospital, Manchester M20 4BX (United Kingdom); Bailey, J [CR-UK/UMIST Radiochemical Targeting and Imaging, Paterson Institute for Cancer Research, Christie Hospital, Manchester M20 4BX (United Kingdom); Chimon, G N [CR-UK/UMIST Radiochemical Targeting and Imaging, Paterson Institute for Cancer Research, Christie Hospital, Manchester M20 4BX (United Kingdom); Clarke, R J [Central Laser Facility, CCLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX110QX (United Kingdom); Neely, D [Central Laser Facility, CCLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX110QX (United Kingdom); Norreys, P A [Central Laser Facility, CCLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX110QX (United Kingdom); Collier, J L [Central Laser Facility, CCLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX110QX (United Kingdom); Singhal, R P [Department of Physics and Astronomy, University of Glasgow G12 8QQ (United Kingdom); Wei, M S [Blackett Laboratory, Imperial College of Science, Technology and Medicine, London SW7 2BZ (United Kingdom)] [and others

    2004-08-21

    Positron emission tomography (PET) is a powerful diagnostic/imaging technique requiring the production of the short-lived positron emitting isotopes {sup 11}C, {sup 13}N, {sup 15}O and {sup 18}F by proton irradiation of natural/enriched targets using cyclotrons. The development of PET has been hampered due to the size and shielding requirements of nuclear installations. Recent results show that when an intense laser beam interacts with solid targets, megaelectronvolt (MeV) protons capable of producing PET isotopes are generated. This report describes how to generate intense PET sources of {sup 11}C and {sup 18}F using a petawatt laser beam. The work describing the laser production of {sup 18}F through a (p,n) {sup 18}O reaction, and the subsequent synthesis of 2-[{sup 18}F] is reported for the first time. The potential for developing compact laser technology for this purpose is discussed.

  19. In vivo neurochemistry with emission tomography and magnetic resonance spectroscopy: clinical applications.

    Science.gov (United States)

    Del Sole, Angelo; Gambini, Anna; Falini, Andrea; Lecchi, Michela; Lucignani, Giovanni

    2002-10-01

    The assessment of neurochemical processes in vivo has received much attention in the past decade as techniques such as positron or single photon emission tomography (PET and SPET), and magnetic resonance spectroscopy (MRS) have become more available. With PET and SPET, basic processes, such as blood flow and oxygen or glucose metabolism, can be regionally assessed, along with more specific functions such as the production, release, and reuptake of neurotransmitters and their occupancy of specific receptors. At the same time, MRS can reveal changes in concentration of several hydrogenate compounds in the brain. All these methods have been extensively applied for research in neurology, and some applications have reached the clinical level, namely for the study of degenerative diseases, motor-neuron diseases, movement disorders, cerebrovascular diseases, and epilepsy. This article focuses on the most relevant information that can be obtained with these complementary techniques to help clinicians in the assessment of neurological diseases.

  20. In vivo neurochemistry with emission tomography and magnetic resonance spectroscopy: clinical applications

    Energy Technology Data Exchange (ETDEWEB)

    Sole, Angelo Del [Azienda Ospedaliera San Paolo e Universita di Milano, 20142 Milan (Italy); Gambini, Anna; Falini, Andrea [IRCCS H San Raffaele e Universita Vita e Salute, 20132 Milan (Italy); Lecchi, Michela [Azienda Ospedaliera L. Sacco e Universita di Milano, 20157 Milan (Italy); Lucignani, Giovanni [Azienda Ospedaliera L. Sacco e Universita di Milano, 20157 Milan (Italy); Universita di Milano, Istituto di Scienze Radiologiche, Cattedra di Medicina Nucleare c/o Ospedale L. Sacco, Via G.B. Grassi, 74, 20157 Milan (Italy)

    2002-10-01

    The assessment of neurochemical processes in vivo has received much attention in the past decade as techniques such as positron or single photon emission tomography (PET and SPET), and magnetic resonance spectroscopy (MRS) have become more available. With PET and SPET, basic processes, such as blood flow and oxygen or glucose metabolism, can be regionally assessed, along with more specific functions such as the production, release, and reuptake of neurotransmitters and their occupancy of specific receptors. At the same time, MRS can reveal changes in concentration of several hydrogenate compounds in the brain. All these methods have been extensively applied for research in neurology, and some applications have reached the clinical level, namely for the study of degenerative diseases, motor-neuron diseases, movement disorders, cerebrovascular diseases, and epilepsy. This article focuses on the most relevant information that can be obtained with these complementary techniques to help clinicians in the assessment of neurological diseases. (orig.)

  1. 18F-fluorodeoxyglucose positron emission tomography predicts survival of patients with neuroendocrine tumors

    DEFF Research Database (Denmark)

    Binderup, Tina; Knigge, Ulrich; Jakobsen, Annika Loft;

    2010-01-01

    -eight prospectively enrolled patients with NE tumors underwent FDG-PET imaging. FDG uptake was quantified by maximal standardized uptake value (SUVmax). The prognostic value of FDG uptake, proliferation index, chromogranin A, and liver metastases were assessed. RESULTS: During the 1-year follow-up, 14 patients died......PURPOSE: (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) is currently not used on a routine basis for imaging of neuroendocrine (NE) tumors. The aim of this study was to investigate the prognostic value of FDG-PET in patients with NE tumors. EXPERIMENTAL DESIGN: Ninety...... was the only predictor of progression-free survival (HR, 8.4; P value of FDG-PET for NE tumors, which exceeds the prognostic value of traditional markers such as Ki67, chromogranin A, and liver metastases. FDG-PET may obtain an important role for NE...

  2. Characterization of hepatic tumors using [11C]metomidate through positron emission tomography

    DEFF Research Database (Denmark)

    Roivainen, Anne; Naum, Alexandru; Nuutinen, Heikki

    2013-01-01

    ABSTRACT: BACKGROUND: Using positron emission tomography (PET), we compared two tracers, [11C]metomidate ([11C]MTO) and [11C]acetate ([11C]ACE), for the characterization of hepatic tumors. METHODS: Thirty-three patients underwent PET with [11C]MTO and [11C]ACE and magnetic resonance imaging (MRI......). Based on the histology of the tumor biopsy, 14 patients had hepatocellular carcinoma (HCC), 9 patients had focal nodular hyperplasia (FNH), and 10 patients had other types of hepatic tumors. Tumor uptake was evaluated by calculating the maximum and mean standardized uptake value and tumor-to-liver ratio....... RESULTS: Altogether, 120 hepatic lesions (59 HCC, 18 FNH, 30 metastases of different primaries, 9 adenomas, and 4 regenerating nodules of liver cirrhosis) were detected by MRI. The overall tumor detection rate was slightly higher for [11C]MTO (39%) than for [11C]ACE (33%). [11C]ACE was more sensitive...

  3. Enhancement of molecular sensitivity in positron emission tomography with quantum correlation of γ-ray photons.

    Science.gov (United States)

    Sato, K; Kobayashi, Y

    2015-05-01

    Enhancement of molecular sensitivity in positron emission tomography (PET) has long been discussed with respect to imaging instrumentation and algorithms for data treatment. Here, the molecular sensitivity in PET is discussed on the basis of 2-dimensional coincident measurements of 511 keV γ ray photons resultant from two-photon annihilation. Introduction of an additional selection window based on the energy sum and difference of the coincidently measured γ ray photons, without any significant instrumental and algorithmic changes, showed an improvement in the signal-to-noise ratio (SNR) by an order of magnitude. Improvement of performance characteristics in the PET imaging system was demonstrated by an increase in the noise equivalent count rate (NECR) which takes both the SNR and the detection efficiency into consideration. A further improvement of both the SNR and the NECR is expected for the present system in real clinical and in-vivo environments, where much stronger positron sources are employed.

  4. EndoTOFPET-US a Novel Multimodal Tool for Endoscopy and Positron Emission Tomography

    CERN Document Server

    Garutti, Erika

    2013-01-01

    The EndoTOFPET-US project aims to jointly exploit Time-Of-Flight Positron Emission Tomography (TOFPET) and ultrasound endoscopy with a multi-modal instrument for the development of new biomarkers for pancreas and prostate oncology. The paper outlines the functionality of the proposed instrument and the challenges for its realization. The high level of miniaturization and integration poses strong demands to the fields of scintillating crystallography, ultra-fast photon detection, highly integrated electronics and system integration. Solutions are presented to obtain a coincidence time resolution better than 200 ps and a spatial resolution of ~1 mm with an asymmetric TOFPET detector. A tracking system with better than 1 mm spatial resolution precision enables the online alignment of the system. The detector design, the production and test status of the single detector

  5. Greater left cerebral hemispheric metabolism in bulimia assessed by positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Wu, J.C.; Hagman, J.; Buchsbaum, M.S.; Blinder, B.; Derrfler, M.; Tai, W.Y.; Hazlett, E.; Sicotte, N. (Univ. of California, Irvine (USA))

    1990-03-01

    Eight women with bulimia and eight age- and sex-matched normal control subjects were studied with positron emission tomography using (18F)-fluorodeoxyglucose (FDG) as a tracer of brain metabolic rate. Subjects performed a visual vigilance task during FDG uptake. In control subjects, the metabolic rate was higher in the right hemisphere than in the left, but patients with bulimia did not have this normal asymmetry. Lower metabolic rates in the basal ganglia, found in studies of depressed subjects, and higher rates in the basal ganglia, reported in a study of anorexia nervosa, were not found. This is consistent with the suggestion that bulimia is a diagnostic grouping distinct from these disorders.

  6. Estimation of intersubject variability of cerebral blood flow measurements using MRI and positron emission tomography

    DEFF Research Database (Denmark)

    Henriksen, Otto Mølby; Larsson, Henrik B W; Hansen, Adam E;

    2012-01-01

    PURPOSE: To investigate the within and between subject variability of quantitative cerebral blood flow (CBF) measurements in normal subjects using various MRI techniques and positron emission tomography (PET). MATERIALS AND METHODS: Repeated CBF measurements were performed in 17 healthy, young...... subjects using three different MRI techniques: arterial spin labeling (ASL), dynamic contrast enhanced T1 weighted perfusion MRI (DCE) and phase contrast mapping (PCM). All MRI measurements were performed within the same session. In 10 of the subjects repeated CBF measurements by (15) O labeled water PET......L/100 g/min, 16.2% and 4.8%, for DCE 43.0 mL/100 g/min, 20.0%, 15.1% and for PET 41.9 mL/100 g/min, 16.5% and 11.9%, respectively. Only for DCE and PCM a significant positive correlation between measurements was demonstrated. CONCLUSION: These findings confirm large between subject variability in CBF...

  7. Nicotine Blocks Brain Estrogen Synthase (Aromatase): In Vivo Positron Emission Tomography Studies in Female Baboons

    Energy Technology Data Exchange (ETDEWEB)

    Biegon, A.; Biegon, A.; Kim, S.-W.; Logan, J.; Hooker, J.M.; Muench, L.; Fowler, J.S.

    2010-01-12

    Cigarette smoking and nicotine have complex effects on human physiology and behavior, including some effects similar to those elicited by inhibition of aromatase, the last enzyme in estrogen biosynthesis. We report the first in vivo primate study to determine whether there is a direct effect of nicotine administration on brain aromatase. Brain aromatase availability was examined with positron emission tomography and the selective aromatase inhibitor [{sup 11}C]vorozole in six baboons before and after exposure to IV nicotine at .015 and .03 mg/kg. Nicotine administration produced significant, dose-dependent reductions in [{sup 11}C]vorozole binding. The amygdala and preoptic area showed the largest reductions. Plasma levels of nicotine and its major metabolite cotinine were similar to those found in cigarette smokers. Nicotine interacts in vivo with primate brain aromatase in regions involved in mood, aggression, and sexual behavior.

  8. An objective evaluation framework for segmentation techniques of functional positron emission tomography studies

    CERN Document Server

    Kim, J; Eberl, S; Feng, D

    2004-01-01

    Segmentation of multi-dimensional functional positron emission tomography (PET) studies into regions of interest (ROI) exhibiting similar temporal behavior is useful in diagnosis and evaluation of neurological images. Quantitative evaluation plays a crucial role in measuring the segmentation algorithm's performance. Due to the lack of "ground truth" available for evaluating segmentation of clinical images, automated segmentation results are usually compared with manual delineation of structures which is, however, subjective, and is difficult to perform. Alternatively, segmentation of co-registered anatomical images such as magnetic resonance imaging (MRI) can be used as the ground truth to the PET segmentation. However, this is limited to PET studies which have corresponding MRI. In this study, we introduce a framework for the objective and quantitative evaluation of functional PET study segmentation without the need for manual delineation or registration to anatomical images of the patient. The segmentation ...

  9. Initial characterization of a position-sensitive photodiode/BGO detector for PET (positron emission tomography)

    Energy Technology Data Exchange (ETDEWEB)

    Derenzo, S.E.; Moses, W.W.; Jackson, H.G.; Turko, B.T.; Cahoon, J.L.; Geyer, A.B.; Vuletich, T.

    1988-11-01

    We present initial results of a position-sensitive photodiode/BGO detector for high resolution, multi-layer positron emission tomography (PET). Position sensitivity is achieved by dividing the 3 mm /times/ 20 mm rectangular photosensitive area along the diagonal to form two triangular segments. Each segment was individually connected to a low-noise amplifier. The photodiodes and crystals were cooled to /minus/100/degree/C to reduce dark current and increase the BGO signal. With an amplifier peaking time of 17 ..mu..sec, the sum of the signals (511 keV photopeak) was 3200 electrons with a full width at half maximum (fwhm) of 750 electrons. The ratio of one signal to the sum determined the depth of interaction with a resolution of 11 mm fwhm. 27 refs., 7 figs.

  10. A New Positron Emission Tomography (PET) Radioligand for Imaging Sigma-1 Receptors in Living Subjects

    DEFF Research Database (Denmark)

    James, Michelle L; Shen, Bin; Zavaleta, Cristina L;

    2012-01-01

    Sigma-1 receptor (S1R) radioligands have the potential to detect and monitor various neurological diseases. Herein we report the synthesis, radiofluorination and evaluation of a new S1R ligand 6-(3-fluoropropyl)-3-(2-(azepan-1-yl)ethyl)benzo[d]thiazol-2(3H)-one ([(18)F]FTC-146, [(18)F]13). [(18)F......]13 was synthesized by nucleophilic fluorination, affording a product with >99% radiochemical purity (RCP) and specific activity (SA) of 2.6 ± 1.2 Ci/µmol (n = 13) at end of synthesis (EOS). Positron emission tomography (PET) and ex vivo autoradiography studies of [(18)F]13 in mice showed high uptake...

  11. Measuring endogenous 5-HT release by emission tomography: promises and pitfalls

    DEFF Research Database (Denmark)

    Paterson, Louise M; Tyacke, Robin J; Nutt, David J;

    2010-01-01

    emission tomography, but has not yet been adequately extended to other neurotransmitter systems. This review focuses on how the technique has been applied to the study of the 5-hydroxytryptamine (5-HT) system. The principles behind visualising fluctuations in neurotransmitters are introduced......, with reference to the dopaminergic system. Studies that aim to image acute, endogenous 5-HT release or depletion at 5-HT receptor targets are summarised, with particular attention to studies in humans. Radiotracers targeting the 5-HT(1A), 5-HT(2A), and 5-HT(4) receptors and the serotonin reuptake transporter...... have been explored for their sensitivity to 5-HT fluctuations, but with mixed outcomes; tracers for these targets cannot reliably image endogenous 5-HT in humans. Shortcomings in our basic knowledge of the mechanisms underlying changes in binding potential are addressed, and suggestions are made...

  12. Hypoxia imaging using Positron Emission Tomography in non-small cell lung cancer: implications for radiotherapy.

    Science.gov (United States)

    Bollineni, Vikram Rao; Wiegman, Erwin M; Pruim, Jan; Groen, Harry J M; Langendijk, Johannes A

    2012-12-01

    Tumour hypoxia is an important contributor to radioresistance. Thus, increasing the radiation dose to hypoxic areas may result in improved locoregional tumour control. However, this strategy requires accurate detection of the hypoxic sub-volume using PET imaging. Secondly, hypoxia imaging may also provide prognostic information and may be of help to monitor treatment response. Therefore, a systematic review of the scientific literature was carried out on the use of Positron Emission Tomography (PET) to image Tumour hypoxia in non-small cell lung cancer (NSCLC). More specifically, the purpose of this review was (1) to summarize the different hypoxia tracers used, (2) to investigate whether Tumour hypoxia can be detected in NSCLC and finally (3) whether the presence of hypoxia can be used to predict outcome.

  13. Imaging amyloid in Parkinson's disease dementia and dementia with Lewy bodies with positron emission tomography.

    Science.gov (United States)

    Brooks, David J

    2009-01-01

    Although Parkinson's disease with later dementia (PDD) and dementia with Lewy bodies (DLB) are pathologically characterized by the presence of intraneuronal Lewy inclusion bodies, amyloid deposition is also associated to varying degrees with both these disorders. Fibrillar amyloid load can now be quantitated in vivo with positron emission tomography (PET) using imaging biomarkers. Here the reported findings of 11C-PIB PET studies concerning the amyloid load associated with PD and its influence on dementia are reviewed. It is concluded that the presence of amyloid acts to accelerate the dementia process in Lewy body disorders, though has little influence on its nature. Anti-amyloid strategies could be a relevant approach for slowing dementia in a number of DLB and PDD cases.

  14. Injectable silver nanosensors: in vivo dosimetry for external beam radiotherapy using positron emission tomography

    DEFF Research Database (Denmark)

    Christensen, Anders Nymark; Rydhög, J. S.; Søndergaard, Rikke Vicki;

    2016-01-01

    Development of safe and efficient radiotherapy routines requires quantification of the delivered absorbed dose to the cancer tissue in individual patients. In vivo dosimetry can provide accurate information about the absorbed dose delivered during treatment. In the current study, a novel silver......-nanosensor formulation based on poly(vinylpyrrolidinone)-coated silver nanoparticles formulated in a gelation matrix composed of sucrose acetate isobutyrate has been developed for use as an in vivo dosimeter for external beam radiotherapy. In situ photonuclear reactions trigger the formation of radioactive (106)Ag......, which enables post treatment verification of the delivered dose using positron emission tomography imaging. The silver-nanosensor was investigated in a tissue equivalent thorax phantom using clinical settings and workflow for both standard fractionated radiotherapy (2 Gy) and stereotactic radiotherapy...

  15. Imaging Atherosclerosis with Hybrid Positron Emission Tomography/Magnetic Resonance Imaging

    DEFF Research Database (Denmark)

    Ripa, Rasmus Sejersten; Kjær, Andreas

    2015-01-01

    Noninvasive imaging of atherosclerosis could potentially move patient management towards individualized triage, treatment, and followup. The newly introduced combined positron emission tomography (PET) and magnetic resonance imaging (MRI) system could emerge as a key player in this context. Both...... PET and MRI have previously been used for imaging plaque morphology and function: however, the combination of the two methods may offer new synergistic opportunities. Here, we will give a short summary of current relevant clinical applications of PET and MRI in the setting of atherosclerosis....... Additionally, our initial experiences with simultaneous PET/MRI for atherosclerosis imaging are presented. Finally, future potential vascular applications exploiting the unique combination of PET and MRI will be discussed....

  16. Short time bacterial endotoxins test for positron emission tomography by means of positively charged filters

    Energy Technology Data Exchange (ETDEWEB)

    Nakazawa, Nobuhiro; Wakita, Kazuo [Nishijin Hospital, Kyoto (Japan); Mineura, Katsuyoshi [Kyoto Prefectural Univ. of Medicine (Japan)] (and others)

    2002-11-01

    Positron emission tomography (PET) radiotracers have very short physical half-lives. It is hard to complete a bacterial endotoxins test prior to release from medical institutes. For endotoxin quantitative determination, limulus amebocyte lysate (LAL) reagent and kinetic-turbidimetry system were previously developed. We investigated the possibility of a short time test by means of positively charged filters. As a result of this study, the effects of positively charged filters on endotoxin removal were over 99.5% for [{sup 18}F]FDG and [{sup 18}F]NaF, which were contaminated with the indicated concentration of endotoxin. Combining this filter and the kinetic-turbidimetric method, it was possible to complete a bacterial endotoxins test in 5 min prior to the patient's administration. This test should be required prior to release for PET radiopharmaceutical quality control. It has been suggested that this combination is a good method for this purpose. (author)

  17. Hot water epilepsy: Phenotype and single photon emission computed tomography observations

    Directory of Open Access Journals (Sweden)

    Mehul Patel

    2014-01-01

    Full Text Available We studied the anatomical correlates of reflex hot water epilepsy (HWE using multimodality investigations viz. magnetic resonance imaging (MRI, electroencephalography (EEG, and single photon emission computed tomography (SPECT. Five men (mean age: 27.0 ΁ 5.8 years with HWE were subjected to MRI of brain, video-EEG studies, and SPECT scan. These were correlated with phenotypic presentations. Seizures could be precipitated in three patients with pouring of hot water over the head and semiology of seizures was suggestive of temporal lobe epilepsy. Ictal SPECT showed hyperperfusion in: left medial temporal - one, left lateral temporal - one, and right parietal - one. Interictal SPECT was normal in all five patients and did not help in localization. MRI and interictal EEG was normal in all the patients. The clinical and SPECT studies suggested temporal lobe as the seizure onset zone in some of the patients with HWE.

  18. Recommendations for measurement of tumour vascularity with positron emission tomography in early phase clinical trials

    Energy Technology Data Exchange (ETDEWEB)

    Aboagye, Eric O.; Kenny, Laura M.; Myers, Melvyn [Imperial College London, Department of Surgery and Cancer, Faculty of Medicine, London (United Kingdom); Gilbert, Fiona J. [University of Cambridge, Radiology Department, Cambridge (United Kingdom); Fleming, Ian N. [University of Aberdeen, NCRI PET Research Network, Aberdeen Bioimaging Centre, Aberdeen (United Kingdom); Beer, Ambros J. [Technische Universitaet Munchen, Klinikum rechts der Isar, Department of Nuclear Medicine, Munich (Germany); Cunningham, Vincent J. [University of Aberdeen, Institute of Medical Sciences, Aberdeen (United Kingdom); Marsden, Paul K. [St. Thomas' Hospital, Division of Imaging Sciences, PET Imaging Centre, London (United Kingdom); Visvikis, Dimitris [INSERM National Institute of Health and Clinical Sciences LaTIM, CHU Morvan, Brest (France); Gee, Antony D. [St. Thomas' Hospital, Division of Imaging Sciences, The Rayne Institute, London (United Kingdom); Groves, Ashley M. [University College London, University College Hospital, Institute of Nuclear Medicine, London (United Kingdom); Cook, Gary J. [St. Thomas' Hospital, KCL Division of Imaging, Sciences and Biomedical Engineering, PET Imaging Centre, London (United Kingdom); Kinahan, Paul E. [University of Washington, 222 Old Fisheries Center (FIS), Box 357987, Seattle, WA (United States); Clarke, Larry [Cancer Imaging Program, Imaging Technology Development Branch, Rockville, MD (United States)

    2012-07-15

    The evaluation of drug pharmacodynamics and early tumour response are integral to current clinical trials of novel cancer therapeutics to explain or predict long term clinical benefit or to confirm dose selection. Tumour vascularity assessment by positron emission tomography could be viewed as a generic pharmacodynamic endpoint or tool for monitoring response to treatment. This review discusses methods for semi-quantitative and quantitative assessment of tumour vascularity. The radioligands and radiotracers range from direct physiological functional tracers like [{sup 15}O]-water to macromolecular probes targeting integrin receptors expressed on neovasculature. Finally we make recommendations on ways to incorporate such measurements of tumour vascularity into early clinical trials of novel therapeutics. (orig.)

  19. Predicting Outcome in Patients with Rhabdomyosarcoma: Role of [{sup 18}F]Fluorodeoxyglucose Positron Emission Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Casey, Dana L. [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Wexler, Leonard H. [Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Fox, Josef J. [Department of Nuclear Medicine, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Dharmarajan, Kavita V. [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai, New York, New York (United States); Schoder, Heiko [Department of Nuclear Medicine, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Price, Alison N. [Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Department of Surgery, Temple University School of Medicine, Philadelphia, Pennsylvania (United States); Wolden, Suzanne L., E-mail: woldens@mskcc.org [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States)

    2014-12-01

    Purpose: To evaluate whether [{sup 18}F]fluorodeoxyglucose positron emission tomography (FDG-PET) response of the primary tumor after induction chemotherapy predicts outcomes in rhabdomyosarcoma (RMS). Methods and Materials: After excluding those with initial tumor resection, 107 patients who underwent FDG-PET after induction chemotherapy at Memorial Sloan Kettering Cancer Center from 2002 to 2013 were reviewed. Local control (LC), progression-free survival (PFS), and overall survival (OS) were calculated according to FDG-PET response and maximum standardized uptake value (SUV) at baseline (PET1/SUV1), after induction chemotherapy (PET2/SUV2), and after local therapy (PET3/SUV3). Receiver operator characteristic curves were used to determine the optimal cutoff for dichotomization of SUV1 and SUV2 values. Results: The SUV1 (<9.5 vs ≥9.5) was predictive of PFS (P=.02) and OS (P=.02), but not LC. After 12 weeks (median) of induction chemotherapy, 45 patients had negative PET2 scans and 62 had positive scans: 3-year PFS was 72% versus 44%, respectively (P=.01). The SUV2 (<1.5 vs ≥1.5) was similarly predictive of PFS (P=.005) and was associated with LC (P=.02) and OS (P=.03). A positive PET3 scan was predictive of worse PFS (P=.0009), LC (P=.05), and OS (P=.03). Conclusions: [{sup 18}F]fluorodeoxyglucose positron emission tomography is an early indicator of outcomes in patients with RMS. Future prospective trials may incorporate FDG-PET response data for risk-adapted therapy and early assessment of new treatment regimens.

  20. Positron emission tomography in pebble beds. Part 1: Liquid particle deposition

    Energy Technology Data Exchange (ETDEWEB)

    Barth, T., E-mail: t.barth@hzdr.de [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Fluid Dynamics (IFD), Bautzner Landstraße 400, 01328 Dresden (Germany); Ludwig, M. [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Fluid Dynamics (IFD), Bautzner Landstraße 400, 01328 Dresden (Germany); Kulenkampff, J.; Gründig, M. [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology (IRE), Permoserstraße 15, 04318 Leipzig (Germany); Franke, K. [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology (IRE), Permoserstraße 15, 04318 Leipzig (Germany); Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmacy (IRP), Permoserstraße 15, 04318 Leipzig (Germany); Lippmann-Pipke, J. [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology (IRE), Permoserstraße 15, 04318 Leipzig (Germany); Hampel, U. [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Fluid Dynamics (IFD), Bautzner Landstraße 400, 01328 Dresden (Germany); Helmholtz-Zentrum Dresden-Rossendorf, AREVA Endowed Chair of Imaging Techniques in Energy and Process Engineering, Technische Universität Dresden, 01062 Dresden (Germany)

    2014-02-15

    Highlights: • Particle deposition in a pebble bed was recorded by positron emission tomography. • The particles were radioactively labelled and their spatial distribution was recorded. • Particle deposition was mainly driven by particle inertia and turbulent dispersion. • Particle deposits form hot spots on the upstream face of the single pebbles. - Abstract: Accidental scenarios such as the depressurisation of the primary circuit of high temperature gas cooled pebble bed reactors may lead to the release of fission products via the discharge of radioactive graphite dust. For a detailed source term assessment in such accident scenarios knowledge of the flow mechanics of dust transport in complex coolant circuit components, like pebble beds, recuperator structures and pipe systems is necessary. In this article an experimental study of aerosol deposition in a pebble bed is described. We investigated the deposition of radiolabelled liquid aerosol particles in a scaled pebble bed in an air-driven small-scale aerosol flow test facility under isothermal ambient conditions. The aerosol particles were generated by means of a condensational aerosol generator with potassium-fluoride (KF) condensation nuclei. Particle concentration measurements upstream and downstream of the pebble bed were performed by isokinetic sampling and particle counting. The results agree with typical deposition curves for turbulent and inertia driven particle deposition. Furthermore, positron emission tomography (PET) was performed to visualize and measure particle deposition distributions in the pebble bed. Results of a selected deposition experiment with moderately large particles (d{sub aero} = 3.5 μm, Re{sup ′}{sub pb}=2200) show that the deposited particles are located in the vicinity of the upstream stagnation points of the pebbles. These findings support the thesis that inertia driven particle deposition is predominating.

  1. 18F-AV-1451 positron emission tomography in Alzheimer's disease and progressive supranuclear palsy.

    Science.gov (United States)

    Passamonti, Luca; Vázquez Rodríguez, Patricia; Hong, Young T; Allinson, Kieren S J; Williamson, David; Borchert, Robin J; Sami, Saber; Cope, Thomas E; Bevan-Jones, W Richard; Jones, P Simon; Arnold, Robert; Surendranathan, Ajenthan; Mak, Elijah; Su, Li; Fryer, Tim D; Aigbirhio, Franklin I; O'Brien, John T; Rowe, James B

    2017-01-24

    The ability to assess the distribution and extent of tau pathology in Alzheimer's disease and progressive supranuclear palsy in vivo would help to develop biomarkers for these tauopathies and clinical trials of disease-modifying therapies. New radioligands for positron emission tomography have generated considerable interest, and controversy, in their potential as tau biomarkers. We assessed the radiotracer (18)F-AV-1451 with positron emission tomography imaging to compare the distribution and intensity of tau pathology in 15 patients with Alzheimer's pathology (including amyloid-positive mild cognitive impairment), 19 patients with progressive supranuclear palsy, and 13 age- and sex-matched controls. Regional analysis of variance and a support vector machine were used to compare and discriminate the clinical groups, respectively. We also examined the (18)F-AV-1451 autoradiographic binding in post mortem tissue from patients with Alzheimer's disease, progressive supranuclear palsy, and a control case to assess the (18)F-AV-1451 binding specificity to Alzheimer's and non-Alzheimer's tau pathology. There was increased (18)F-AV-1451 binding in multiple regions in living patients with Alzheimer's disease and progressive supranuclear palsy relative to controls [main effect of group, F(2,41) = 17.5, P Alzheimer's disease, relative to patients with progressive supranuclear palsy and with control subjects, in the hippocampus and in occipital, parietal, temporal, and frontal cortices (t's > 2.2, P's Alzheimer's disease, (18)F-AV-1451 binding was elevated in the midbrain (t = 2.1, P 2.7, P's Alzheimer's disease and to distinguish it from other tauopathies with distinct clinical and pathological characteristics such as progressive supranuclear palsy.

  2. MeV-range velocity-space tomography from gamma-ray and neutron emission spectrometry measurements at JET

    DEFF Research Database (Denmark)

    Salewski, Mirko; Nocente, M.; Jacobsen, Asger Schou

    2017-01-01

    We demonstrate the measurement of a 2D MeV-range ion velocity distribution function by velocity-space tomography at JET. Deuterium ions were accelerated into the MeV-range by third harmonic ion cyclotron resonance heating. We made measurements with three neutron emission spectrometers and a high-...

  3. 76 FR 6143 - Draft Guidance on Positron Emission Tomography Drug Applications-Content and Format for New Drug...

    Science.gov (United States)

    2011-02-03

    ... Applications--Content and Format for New Drug Applications and Abbreviated New Drug Applications; Availability... emission tomography (PET) drugs in submitting new drug applications (NDAs) or abbreviated new drug... Content and Format of New Drug Applications and Abbreviated New Drug Applications for Certain......

  4. Serotonin transporter in attention-deficit hyperactivity disorder--preliminary results from a positron emission tomography study.

    Science.gov (United States)

    Karlsson, Linnea; Tuominen, Lauri; Huotarinen, Antti; Leppämäki, Sami; Sihvola, Elina; Helin, Semi; Sipilä, Maria; Tani, Pekka; Hirvonen, Jussi; Hietala, Jarmo; Karlsson, Hasse

    2013-05-30

    The serotonin transporter (SERT) in attention-deficit hyperactivity disorder (ADHD) patients has not been explored by earlier positron emission tomography (PET) studies. We measured SERT availability in female ADHD patients (n=8) and healthy controls (n=14) with PET and [11C]MADAM as a tracer. No significant group differences in [11C]MADAM binding potential were noted.

  5. Regional myocardial oxygen consumption estimated by carbon-11 acetate and positron emission tomography before and after repetitive ischemia

    DEFF Research Database (Denmark)

    Kofoed, K F; Hansen, P R; Holm, S

    2011-01-01

    Preserved myocardial oxygen consumption estimated by carbon 11-acetate and positron emission tomography (PET) in myocardial regions with chronic but reversibly depressed contractile function in patients with ischemic heart disease have been suggested to be caused by repeated short episodes of acu...

  6. Better yield of (18)fluorodeoxyglucose-positron emission tomography in patients with metastatic differentiated thyroid carcinoma during thyrotropin stimulation

    NARCIS (Netherlands)

    van Tol, KM; Jager, PL; Piers, DA; Pruim, J; de Vries, EGE; Dullaart, RPF; Links, TP

    2002-01-01

    To determine whether (18)fluorodeoxyglucose-positron emission tomography (FDG-PET) for the detection of recurrences or metastases of differentiated thyroid carcinoma should be performed during thyrotropin (TSH) suppression or TSH stimulation, eight patients were studied sequentially. After the secon

  7. Integration of Quantitative Positron Emission Tomography Absolute Myocardial Blood Flow Measurements in the Clinical Management of Coronary Artery Disease.

    Science.gov (United States)

    Gewirtz, Henry; Dilsizian, Vasken

    2016-05-31

    In the >40 years since planar myocardial imaging with(43)K-potassium was introduced into clinical research and management of patients with coronary artery disease (CAD), diagnosis and treatment have undergone profound scientific and technological changes. One such innovation is the current state-of-the-art hardware and software for positron emission tomography myocardial perfusion imaging, which has advanced it from a strictly research-oriented modality to a clinically valuable tool. This review traces the evolving role of quantitative positron emission tomography measurements of myocardial blood flow in the evaluation and management of patients with CAD. It presents methodology, currently or soon to be available, that offers a paradigm shift in CAD management. Heretofore, radionuclide myocardial perfusion imaging has been primarily qualitative or at best semiquantitative in nature, assessing regional perfusion in relative terms. Thus, unlike so many facets of modern cardiovascular practice and CAD management, which depend, for example, on absolute values of key parameters such as arterial and left ventricular pressures, serum lipoprotein, and other biomarker levels, the absolute levels of rest and maximal myocardial blood flow have yet to be incorporated into routine clinical practice even in most positron emission tomography centers where the potential to do so exists. Accordingly, this review focuses on potential value added for improving clinical CAD practice by measuring the absolute level of rest and maximal myocardial blood flow. Physiological principles and imaging fundamentals necessary to understand how positron emission tomography makes robust, quantitative measurements of myocardial blood flow possible are highlighted.

  8. Lhermitte-Duclos disease presenting with positron emission tomography-magnetic resonance fusion imaging: a case report

    Directory of Open Access Journals (Sweden)

    Calabria Ferdinando

    2012-03-01

    Full Text Available Abstract Introduction Lhermitte-Duclos disease or dysplastic gangliocytoma of the cerebellum is an extremely rare tumor. It is a slowly enlarging mass within the cerebellar cortex. The majority of cases are diagnosed in the third or fourth decade of life. Case presentation We report the case of a 37-year-old Caucasian woman who underwent positron emission tomography-computed tomography with fluorine-18-fluorodeoxyglucose for evaluation of a solitary lung node. No pathological uptake was detected in the solitary lung node but the positron emission tomography-computed tomography of her brain showed intense tracer uptake, suggestive of a malignant neoplasm, in a mass in her left cerebellar lobe. Our patient had experienced two years of occipital headache and movement disorder. Subsequently, magnetic resonance imaging was performed with contrast agent administration, showing a large subtentorial mass in her left cerebellar hemisphere, with compression and dislocation of the fourth ventricle. Metabolic data provided by positron emission tomography and morphological magnetic resonance imaging views were fused in post-processing, allowing a diagnosis of dysplastic gangliocytoma with increased glucose metabolism. Total resection of the tumor was performed and histological examination confirmed the diagnosis of Lhermitte-Duclos disease. Conclusions Our case indicates that increased uptake of fluorine-18-fluorodeoxyglucose may be misinterpreted as a neoplastic process in the evaluation of patients with Lhermitte-Duclos disease, but supports the usefulness of integrated positron emission tomography-magnetic resonance imaging in the exact pathophysiologic explanation of this disease and in making the correct diagnosis. However, an accurate physical examination and exact knowledge of clinical data is of the utmost importance.

  9. Attenuation correction in pulmonary and myocardial single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Almquist, H

    2000-01-01

    The objective was to develop and validate methods for single photon emission computed tomography, SPECT, allowing quantitative physiologic and diagnostic studies of lung and heart. A method for correction of variable attenuation in SPECT, based on transmission measurements before administration of an isotope to the subject, was developed and evaluated. A protocol based upon geometrically well defined phantoms was developed. In a mosaic pattern phantom count rates were corrected from 39-43% to 101-110% of reference. In healthy subjects non-gravitational pulmonary perfusion gradients observed without attenuation correctionwere artefacts caused by attenuation. Pulmonary density in centre of right lung, obtained from the transmission measurement, was 0.28 {+-} 0.03 g/ml in normal subjects. Mean density was lower in large lungs compared to smaller ones. We also showed that regional ventilation/perfusion ratios could be measured with SPECT, using the readily available tracer {sup 133}Xe. Because of the low energy of {sup 133}Xe this relies heavily upon attenuation correction. A commercially available system for attenuation correction with simultaneous emission and transmission, considered to improve myocardial SPECT, performed erroneously. This could lead to clinical misjudgement. We considered that manufacturer-independent pre-clinical tests are required. In a test of two other commercial systems, based on different principles, an adapted variant of our initial protocol was proven useful. Only one of the systems provided correct emission count rates independently on phantom configuration. Errors in the other system were related to inadequate compensation of the influence of emission activity on the transmission study.

  10. Sensitivity estimation in time-of-flight list-mode positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Herraiz, J. L. [Madrid-MIT M+Visión Consortium, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 and Grupo de Física Nuclear, Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, CEI Moncloa, Madrid 28040 (Spain); Sitek, A., E-mail: sarkadiu@gmail.com [Center for Advanced Medical Imaging Sciences, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114 (United States)

    2015-11-15

    Purpose: An accurate quantification of the images in positron emission tomography (PET) requires knowing the actual sensitivity at each voxel, which represents the probability that a positron emitted in that voxel is finally detected as a coincidence of two gamma rays in a pair of detectors in the PET scanner. This sensitivity depends on the characteristics of the acquisition, as it is affected by the attenuation of the annihilation gamma rays in the body, and possible variations of the sensitivity of the scanner detectors. In this work, the authors propose a new approach to handle time-of-flight (TOF) list-mode PET data, which allows performing either or both, a self-attenuation correction, and self-normalization correction based on emission data only. Methods: The authors derive the theory using a fully Bayesian statistical model of complete data. The authors perform an initial evaluation of algorithms derived from that theory and proposed in this work using numerical 2D list-mode simulations with different TOF resolutions and total number of detected coincidences. Effects of randoms and scatter are not simulated. Results: The authors found that proposed algorithms successfully correct for unknown attenuation and scanner normalization for simulated 2D list-mode TOF-PET data. Conclusions: A new method is presented that can be used for corrections for attenuation and normalization (sensitivity) using TOF list-mode data.

  11. Graphics processing unit (GPU)-accelerated particle filter framework for positron emission tomography image reconstruction.

    Science.gov (United States)

    Yu, Fengchao; Liu, Huafeng; Hu, Zhenghui; Shi, Pengcheng

    2012-04-01

    As a consequence of the random nature of photon emissions and detections, the data collected by a positron emission tomography (PET) imaging system can be shown to be Poisson distributed. Meanwhile, there have been considerable efforts within the tracer kinetic modeling communities aimed at establishing the relationship between the PET data and physiological parameters that affect the uptake and metabolism of the tracer. Both statistical and physiological models are important to PET reconstruction. The majority of previous efforts are based on simplified, nonphysical mathematical expression, such as Poisson modeling of the measured data, which is, on the whole, completed without consideration of the underlying physiology. In this paper, we proposed a graphics processing unit (GPU)-accelerated reconstruction strategy that can take both statistical model and physiological model into consideration with the aid of state-space evolution equations. The proposed strategy formulates the organ activity distribution through tracer kinetics models and the photon-counting measurements through observation equations, thus making it possible to unify these two constraints into a general framework. In order to accelerate reconstruction, GPU-based parallel computing is introduced. Experiments of Zubal-thorax-phantom data, Monte Carlo simulated phantom data, and real phantom data show the power of the method. Furthermore, thanks to the computing power of the GPU, the reconstruction time is practical for clinical application.

  12. An automatic classification technique for attenuation correction in positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Bettinardi, V.; Pagani, E.; Gilardi, M.C.; Landoni, C.; Riddell, C.; Rizzo, G.; Castiglioni, I.; Belluzzo, D.; Lucignani, G.; Fazio, F. [INB-CNR, Scientific Inst. H San Raffaele, Univ. of Milan (Italy); Schubert, S. [GE Medical System, Milwaukee, WI (United States)

    1999-05-01

    In this paper a clustering technique is proposed for attenuation correction (AC) in positron emission tomography (PET). The method is unsupervised and adaptive with respect to counting statistics in the transmission (TR) images. The technique allows the classification of pre- or post-injection TR images into main tissue components in terms of attenuation coefficients. The classified TR images are then forward projected to generate new TR sinograms to be used for AC in the reconstruction of the corresponding emission (EM) data. The technique has been tested on phantoms and clinical data of brain, heart and whole-body PET studies. The method allows: (a) reduction of noise propagation from TR into EM images, (b) reduction of TR scanning to a few minutes (3 min) with maintenance of the quantitative accuracy (within 6%) of longer acquisition scans (15-20 min), (c) reduction of the radiation dose to the patient, (d) performance of quantitative whole-body studies. (orig.) With 8 figs., 4 tabs., 25 refs.

  13. Evaluation of non-uniform attenuation correction using simultaneous transmission and emission computed tomography. Basic analysis with myocardial phantom

    Energy Technology Data Exchange (ETDEWEB)

    Otake, Hidenori; Yukihiro, Masashi; Fukushima, Yumi [Gunma Univ., Maebashi (Japan). School of Medicine] [and others

    1996-03-01

    Simultaneous transmission emission protocol (STEP), developed for the non-uniform attenuation correction of single photon emission computed tomography (SPECT) was evaluated using the cardiac phantom prepared with and without a myocardial wall defect. Emission computed tomography (ECT) of the cardiac phantom using {sup 201}Tl was acquired. Transmission data (TCT) were taken using a line source of {sup 99m}Tc. Myocardial images with STEP method were superior in the homogeneity of intramyocardial radioactivity and spatial resolution to the conventional SPECT images. This is an excellent method because of the accurate matching position between TCT and ECT images and shortening the examination time by simultaneous data acquisition. It would be clinically useful for diagnosing various myocardial diseases. (author).

  14. [Evaluation of non-uniform attenuation correction using simultaneous transmission and emission computed tomography--basic analysis with myocardial phantom].

    Science.gov (United States)

    Otake, H; Yukihiro, M; Fukushima, Y; Imai, T; Hosono, K; Hatori, N; Watanabe, N; Hirano, T; Inoue, T; Takahashi, M; Ban, R; Endo, K

    1996-03-01

    Simultaneous transmission emission protocol (STEP), developed for the non-uniform attenuation correction of single photon emission computed tomography (SPECT) was evaluated using the cardiac phantom prepared with and without a myocardial wall defect. Emission computed tomography (ECT) of the cardiac phantom using 201Tl was acquired. Transmission data (TCT) were taken using a line source of 99mTc. Myocardial images with STEP method were superior in the homogeneity of intramyocardial radioactivity and spatial resolution to the conventional SPECT images. This is an excellent method because of the accurate matching position between TCT and ECT images and shortening the examination time by simultaneous data acquisition. It would be clinically useful for diagnosing various myocardial diseases.

  15. Extrapulmonary Small Cell Carcinoma of the Seminal Vesicles and Prostate Demonstrated on 18F-FDG Positron Emission Tomography/Computed Tomography.

    Science.gov (United States)

    Tabrizipour, Amir Iravani; Shen, Lily; Mansberg, Robert; Chuong, Bui

    2016-02-01

    Extrapulmonary primary small cell carcinomas arising from the urogenital tract is infrequent. It can rarely arise from the prostate and even more rarely from the seminal vesicles. We present a 79-year-old male who was admitted due to acute renal failure with a history of radical radiotherapy for prostate adenocarcinoma 13 years ago. The prostate specific antigen level was not elevated. An abdominopelvic computed tomography (CT) scan showed markedly enlarged seminal vesicles causing bilateral ureteral obstruction and a mildly enlarged prostate. Further evaluation with fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography/CT demonstrated extensive 18F-FDG uptake in the pelvis with diffuse involvement of both seminal vesicles and the prostate without pathologic uptake in the lungs or elsewhere in the body. Core biopsies of the prostate and both seminal vesicles revealed diffuse involvement by small cell carcinoma. Therapy could not be instituted due to a rapid deterioration in the patient's clinical condition.

  16. Hypermetabolic Calcified Lymph Nodes on 18Fludeoxyglucose-Positron Emission Tomography/Computed Tomography in a Case of Treated Ovarian Cancer Recurrence: Residual Disease or Benign Formation?

    Directory of Open Access Journals (Sweden)

    Alexandra Nikaki

    2016-06-01

    Full Text Available The contribution of positron emission tomography/computed tomography (PET/CT with 18F-fludeoxyglucose (FDG in evaluating ovarian cancer recurrence even after a prolonged disease-free interval, and in therapy response is well-described. Calcifications observed in CT, although usually attributed to benign conditions, may actually represent active disease. Such an example of calcified formations is psammoma bodies. We present a case of 56-y. o. patient with ovarian cancer relapse at the supraclavicular area 18 years after complete response and disease-free interval. The patient received chemotherapy and underwent 18F-FDG-PET/CT for the evaluation of treatment response. Both CT corrected and uncorrected PET images showed hypermetabolism in the massively calcified lymph nodes in the neck, mediastinum, axilla and abdomen, indicative of active residual disease

  17. [18F]fluoromethylcholine (FCH) positron emission tomography/computed tomography (PET/CT) for lymph node staging of prostate cancer: a prospective study of 210 patients

    DEFF Research Database (Denmark)

    Poulsen, Mads H; Bouchelouche, Kirsten; Høilund-Carlsen, Poul F

    2012-01-01

    this procedure. However, we did detect several bone metastases with [(18) F]FCH PET/CT that the normal bone scans had missed, and this might be worth pursuing. OBJECTIVES: •  To assess the value of [(18) F]fluoromethylcholine (FCH) positron emission tomography/computed tomography (PET/CT) for lymph node (LN....... •  The mean diameter of the true positive LN metastases was significantly larger than that of the false negative LNs (10.3 vs 4.6 mm; P bone uptake, consistent with bone metastases, in 18 patients, 12 of which had histologically benign LNs. CONCLUSIONS......: •  Due to a relatively low sensitivity and a correspondingly rather low PPV, FCH PET/CT is not ideal for primary LN staging in patients with prostate cancer. •  However, FCH PET/CT does convey important additional information otherwise not recognised, especially for bone metastases....

  18. Gallium-68 DOTA-TATE Positron Emission Tomography/Computed Tomography: Scintigraphic Changes of Adrenal Glands Following Management of Ectopic Cushing's Syndrome by Steroidogenesis Inhibitors.

    Science.gov (United States)

    Huang, Yu-Ting; Aziz, Shaikh Irfan; Ravi Kumar, Aravind S

    2014-09-01

    In the era of emerging functional imaging techniques, an understanding of the effects of hormonal therapies on the scintigraphic appearance of endocrine organs is desirable to minimize the erroneous scan interpretation. The mechanisms by which changes in the scintigraphic appearance of endocrine organs occur however sometimes remain ambiguous. This case demonstrates the gallium-68 (Ga-68) DOTA-TATE positron emission tomography/computed tomography (CT) appearance of adrenal glands following management with steroidogenesis inhibitors. The potential mechanisms underlying this change are discussed. A 17-year-old boy with adrenocorticotropic hormone (ACTH) dependent Cushing's syndrome secondary to ectopic ACTH secretion underwent pre- and post-metyrapone and dexamethasone treatment Ga-68 DOTA-TATE scans 4 months apart. Pretreatment, both adrenals demonstrated normal symmetrical prominent Ga-68 DOTA-TATE uptake and normal CT appearance. The posttherapy scan revealed marked symmetrical suppression of Ga-68 DOTA-TATE uptake, but with bilateral adrenal hypertrophy on CT.

  19. Isolated thymic Langerhans cell histiocytosis discovered on F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT)

    Energy Technology Data Exchange (ETDEWEB)

    Turpin, Sophie [CHU Sainte-Justine, Nuclear Medicine, Montreal (Canada); Carret, Anne-Sophie [CHU Sainte-Justine, Hemato-Oncology, Montreal (Canada); Dubois, Josee [CHU Sainte-Justine, Radiology, Montreal (Canada); Buteau, Chantal [CHU Sainte-Justine, Infectious Diseases, Montreal (Canada); Patey, Natalie [CHU Sainte-Justine, Pathology, Montreal (Canada)

    2015-11-15

    The thymic infiltration in young patients with multisystemic Langerhans cell histiocytosis and its radiologic features are well known. However, isolated thymic disease has seldom been reported in the literature. We report the case of a 10-month-old child admitted for fever of unknown origin. Whole-body F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) was performed to identify a focus of infection. It demonstrated an unusual aspect of the thymus, which led to further investigation and revealed isolated infiltration of the thymus by Langerhans cell histiocytosis. The patient was treated accordingly and is now disease free. As evaluation of Langerhans cell histiocytosis patients with F-18 FDG PET/CT is becoming more frequent, it is important to be aware of the scintigraphical characteristics of thymic Langerhans cell histiocytosis. (orig.)

  20. Impact of 18-fluorodeoxyglucose positron emission tomography on computed tomography defined target volumes in radiation treatment planning of esophageal cancer : reduction in geographic misses with equal inter-observer variability

    NARCIS (Netherlands)

    Schreurs, Liesbeth; Busz, D. M.; Paardekooper, G. M. R. M.; Beukema, J. C.; Jager, P. L.; Van der Jagt, E. J.; van Dam, G. M.; Groen, H.; Plukker, J. Th. M.; Langendijk, J. A.

    2010-01-01

    P>Target volume definition in modern radiotherapy is based on planning computed tomography (CT). So far, 18-fluorodeoxyglucose positron emission tomography (FDG-PET) has not been included in planning modality in volume definition of esophageal cancer. This study evaluates fusion of FDG-PET and CT in

  1. Early Lung Cancer Detection Using Spiral Computed Tomography and Positron Emission Tomography%低剂量螺旋GT与PET联合筛查早期肺癌的研究

    Institute of Scientific and Technical Information of China (English)

    屈婉莹; 周清

    2007-01-01

    @@ 1 文献类型 诊断. 2证据水平 2b. 3文献来源 Bastarrika G,Garcia-Velloso MJ,Lozano MD et al. Early lung cancer detection using spiral computed tomography and positron emission tomography[J].Am J Respir Crit Care Med,2005,171(12):1378-1383.

  2. Two Cases of Legionella pneumophila Pneumonia with Prolonged Neurologic Symptoms and Brain Hypoperfusion on Single-Photon Emission Computed Tomography

    Directory of Open Access Journals (Sweden)

    Hiromitsu Ohta

    2016-01-01

    Full Text Available Cerebral and cerebellar symptoms are frequently associated with Legionnaires’ disease. However, corresponding brain lesions are difficult to demonstrate using either computed tomography (CT or magnetic resonance imaging (MRI. We report here two patients with Legionella pneumophila pneumonia accompanied by prolonged neurologic symptoms. In contrast to brain CT and MRI, which failed to detect any abnormalities, single-photon emission computed tomography (SPECT showed multiple sites of hypoperfusion within the brains of both patients. These cases suggest that vasculopathy, which is detectable by SPECT, might be one of the causes of neurologic symptoms in patients with Legionnaires’ disease.

  3. Normal Positron Emission Tomography-Computerized Tomogram in a Patient with Apparent Mesenteric Panniculitis: Biopsy Is Still the Answer

    Directory of Open Access Journals (Sweden)

    Eli D. Ehrenpreis

    2009-04-01

    Full Text Available Mesenteric panniculitis (also known as sclerosing mesenteritis is a chronic inflammatory disease of the mesenteric connective tissue. It is known to have a wide spectrum of clinical and radiological presentations. In general, biopsy is recommended for diagnosis; however, a recent study proposed that a negative positron emission tomography- computerized tomography (PET-CT scan is accurate in differentiating benign and neoplastic mesenteric processes [Br J Radiol 2006;79:37–43]. The following case report questions the accuracy of PET-CT in this setting and confirms the requirement for biopsy to rule out the presence of mesenteric lymphoma.

  4. Utility of positron emission tomography for tumour surveillance in children with neurofibromatosis type 1

    Energy Technology Data Exchange (ETDEWEB)

    Moharir, Mahendranath [Hospital for Sick Children, Division of Neurology, Ontario (Canada); London, Kevin [Children' s Hospital at Westmead, Department of Nuclear Medicine, Sydney (Australia); Howman-Giles, Robert [University of Sydney, Discipline of Imaging, Faculty of Medicine, Sydney (Australia); North, Kathryn [Children' s Hospital at Westmead, Institute for Neuroscience and Muscle Research, Sydney, NSW (Australia)

    2010-07-15

    There is little consensus regarding optimal surveillance of optic pathway glioma (OPG) and plexiform neurofibroma (PNF) in childhood neurofibromatosis type 1 (NF1). {sup 18}F-2-Fluoro-2-deoxy-D-glucose (FDG) positron emission tomography and computed tomography (PET/CT) is employed in the surveillance of adult PNFs; but its utility has neither been specifically studied in children with PNFs nor in children with OPG. Review of PET/CT studies was performed in NF1 children with OPG or PNF. FDG-avidity of tumours was semi-quantitatively analysed and graded by calculating the maximum standardised uptake value (SUV{sub max}) [grade 1: <3 (low), grade 2: >3-<4 (intermediate), grade 3: >4 (intense)]. Eighteen children (ten girls; median age: 8.5-years) had PET/CT. Nineteen OPGs were imaged. The SUV{sub max} could be measured in 16. Ten were grade 1 and three each were grade 2 and grade 3. FDG-avidity reduced from grade 3 to grade 1 in two symptomatic OPGs following chemotherapy and this was associated with clinical improvement. PET/CT diagnosed symptomatic OPGs with a sensitivity of 0.625 [95% confidence interval (CI): 0.259-0.897] and specificity of 0.875 (95% CI: 0.466-0.993). Sixteen PNFs were imaged. Twelve were grade 1 and two each were grade 2 and grade 3. The two grade 3 PNFs were confirmed malignant peripheral nerve sheath tumours. PET/CT diagnosed malignant transformation with a sensitivity of 1.0 (95% CI: 0.197-1.0) and specificity of 0.857 (95% CI: 0.561-0.974). PET/CT may contribute useful information to the surveillance of OPG in childhood NF1 - particularly to identify progressive, symptomatic tumours. As in adults, PET/CT is useful for the detection of malignant transformation in PNFs in children with NF1. (orig.)

  5. Brain glucose utilization in systemic lupus erythematosus with neuropsychiatric symptoms: a controlled positron emission tomography study

    Energy Technology Data Exchange (ETDEWEB)

    Otte, A. [Institute of Nuclear Medicine, University Hospital, Basel (Switzerland)]|[Department of Nuclear Medicine, University Hospital Freiburg (Germany); Weiner, S.M. [Department of Rheumatology and Immunology, University Hospital Freiburg (Germany); Peter, H.H. [Department of Rheumatology and Immunology, University Hospital Freiburg (Germany); Mueller-Brand, J. [Institute of Nuclear Medicine, University Hospital, Basel (Switzerland); Goetze, M. [Institute of Nuclear Medicine, University Hospital, Basel (Switzerland); Moser, E. [Department of Nuclear Medicine, University Hospital Freiburg (Germany); Gutfleisch, J. [Department of Rheumatology and Immunology, University Hospital Freiburg (Germany); Hoegerle, S. [Department of Nuclear Medicine, University Hospital Freiburg (Germany); Juengling, F.D. [Department of Nuclear Medicine, University Hospital Freiburg (Germany); Nitzsche, E.U. [Department of Nuclear Medicine, University Hospital Freiburg (Germany)

    1997-07-01

    In contrast to morphological imaging [such as magnetic resonance imaging (MRI) or computed tomography], functional imaging may be of advantage in the detection of brain abnormalities in cases of neuropsychiatric systemic lupus erythematosus (SLE). Therefore, we studied 13 patients (aged 40{+-}14 years, 11 female, 2 male) with neuropsychiatric SLE who met four of the American Rheumatism Association criteria for the classification of SLE. Ten clinically and neurologically healthy volunteers served as controls (aged 40{+-}12 years, 5 female, 5 male). Both groups were investigated using fluorine-18-labelled fluorodeoxyglucose brain positron emission tomography (PET) and cranial MRI. The normal controls and 11 of the 13 patients showed normal MRI scans. However, PET scan was abnormal in all 13 SLE patients. Significant group-to-group differences in the glucose metabolic index (GMI=region of interest uptake/global uptake at the level of the basal ganglia and thalamus) were found in the parieto-occipital region on both sides: the GMI of the parieto-occipital region on the right side was 0.922{+-}0.045 in patients and 1.066{+-}0.081 in controls (P<0.0001, Mann Whitney U test), while on the left side it was 0.892{+-}0.060 in patients and 1.034{+-}0.051 in controls (P=0.0002). Parieto-occipital hypometabolism is a conspicuous finding in mainly MRI-negative neuropsychiatric SLE. As the parieto-occipital region is located at the boundary of blood supply of all three major arteries, it could be the most vulnerable zone of the cerebrum and may be affected at an early stage of the cerebrovascular disease. (orig.). With 1 fig., 1 tab.

  6. Safety of ventilation/perfusion single photon emission computed tomography for pulmonary embolism diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Le Roux, Pierre-Yves; Palard, Xavier; Robin, Philippe; Abgral, Ronan; Querellou, Solene; Salaun, Pierre-Yves [Universite Europeenne de Bretagne, Brest (France); Universite de Brest, Brest (France); CHRU de la Cavale Blanche, Service de medecine nucleaire, Brest (France); Delluc, Aurelien; Couturaud, Francis [Universite Europeenne de Bretagne, Brest (France); Universite de Brest, Brest (France); CHRU de la Cavale Blanche, Departement de medecine interne et de pneumologie, Brest (France); Le Gal, Gregoire [Universite Europeenne de Bretagne, Brest (France); University of Ottawa, Ottawa Hospital Research Institute, Ottawa (Canada); CHRU de la Cavale Blanche, Departement de medecine interne et de pneumologie, Brest (France); Universite de Brest, Brest (France)

    2014-10-15

    The aim of this management outcome study was to assess the safety of ventilation/perfusion single photon emission computed tomography (V/Q SPECT) for the diagnosis of pulmonary embolism (PE) using for interpretation the criteria proposed in the European Association of Nuclear Medicine (EANM) guidelines for V/Q scintigraphy. A total of 393 patients with clinically suspected PE referred to the Nuclear Medicine Department of Brest University Hospital from April 2011 to March 2013, with either a high clinical probability or a low or intermediate clinical probability but positive D-dimer, were retrospectively analysed. V/Q SPECT were interpreted by the attending nuclear medicine physician using a diagnostic cut-off of one segmental or two subsegmental mismatches. The final diagnostic conclusion was established by the physician responsible for patient care, based on clinical symptoms, laboratory test, V/Q SPECT and other imaging procedures performed. Patients in whom PE was deemed absent were not treated with anticoagulants and were followed up for 3 months. Of the 393 patients, the prevalence of PE was 28 %. V/Q SPECT was positive for PE in 110 patients (28 %) and negative in 283 patients (72 %). Of the 110 patients with a positive V/Q SPECT, 78 (71 %) had at least one additional imaging test (computed tomography pulmonary angiography or ultrasound) and the diagnosis of PE was eventually excluded in one patient. Of the 283 patients with a negative V/Q SPECT, 74 (26 %) patients had another test. The diagnosis of PE was finally retained in one patient and excluded in 282 patients. The 3-month thromboembolic risk in the patients not treated with anticoagulants was 1/262: 0.38 % (95 % confidence interval 0.07-2.13). A diagnostic management including V/Q SPECT interpreted with a diagnostic cut-off of ''one segmental or two subsegmental mismatches'' appears safe to exclude PE. (orig.)

  7. Use of fluorine-18 fluorodeoxyglucose positron emission tomography in the detection of thymoma: a preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    Liu Renshyan [National PET/Cyclotron Center and Dept. of Nuclear Medicine, Taipei Veterans General Hospital and National Yang-Ming Univ. School of Medicine, Taipei (Taiwan, Province of China)]|[National Def. Medical Center, Taipei (Taiwan, Province of China); Yeh Shinhwa [National PET/Cyclotron Center and Dept. of Nuclear Medicine, Taipei Veterans General Hospital and National Yang-Ming Univ. School of Medicine, Taipei (Taiwan, Province of China); Huang Minhsiung [Div. of Thoracic Surgery, Taipei Veterans General Hospital and National Yang-Ming Univ. School of Medicine, Taipei (Taiwan, Province of China); Wang Liangshun [Div. of Thoracic Surgery, Taipei Veterans General Hospital and National Yang-Ming Univ. School of Medicine, Taipei (Taiwan, Province of China); Chu Leeshing [National PET/Cyclotron Center and Dept. of Nuclear Medicine, Taipei Veterans General Hospital and National Yang-Ming Univ. School of Medicine, Taipei (Taiwan, Province of China)]|[National Def. Medical Center, Taipei (Taiwan, Province of China); Chang Chenpei [National PET/Cyclotron Center and Dept. of Nuclear Medicine, Taipei Veterans General Hospital and National Yang-Ming Univ. School of Medicine, Taipei (Taiwan, Province of China); Chu Yumkung [National PET/Cyclotron Center and Dept. of Nuclear Medicine, Taipei Veterans General Hospital and National Yang-Ming Univ. School of Medicine, Taipei (Taiwan, Province of China); Wu Lingchi [National PET/Cyclotron Center and Dept. of Nuclear Medicine, Taipei Veterans General Hospital and National Yang-Ming Univ. School of Medicine, Taipei (Taiwan, Province of China)

    1995-12-01

    This study aimed to analyse the uptake patterns of fluorine-18 fluorodeoxyglucose (FDG) in thymomas of different stages. FDG positron emission tomography (PET) scan was performed in 12 patients suspected of having thymoma and in nine controls. Qualitative visual interpretation was used to detect the foci with FDG uptake higher than that of normal mediastinum. Tumour/lung ratio (TLR) was calculated from the counts of ROIs over the mass and over comparable normal lung tissue in thymoma patients. Mediastinum/lung ratio (MLR) was calculated from the counts of ROIs over the anterior mediastinum and lung in controls. The PET scan patterns of distribution of foci with FDG uptake and TLRs were correlated with the computed tomography (CT) of magnetic resonance imaging (MRI) findings, and staging of the thymomas. Thymectomy was performed in ten patients and thoracoscopy was done in two patients. The results revealed ten thymomas (two stage I tumours, two stage II, four stage III and two stage IV, according to the Masaoka classification), and two cases of thymic hyperplasia associated with myasthenia gravis. Myasthenia gravis was also noted in four thymoma patients. FDG studies showed (a) diffuse uptake in the widened anterior mediastinum in patients with thymic hyperplasia, (b) confined focal FDG uptake in the non-invasive or less invasive, stage I and II thymomas, and (c) multiple discrete foci of FDG uptake in the mediastinum and thoraci structures in stage III and IV advanced invasive thymomas. The thymomas had the highest TLRs, followed by the TLRs of thymic hyperplasia and the MLRs of control subjects. No significant difference was found between thymomas in different stages or between thymomas with and thymomas without myasthenia gravis. In comparison with CT and/or MRI, FDG/PET detected more lesions in patients with invasive thymomas and downgraded the staging of thymoma in four patients. (orig./MG)

  8. Fluorodeoxyglucose positron emission tomography in the initial staging of germ cell tumours

    Energy Technology Data Exchange (ETDEWEB)

    Hain, S.F.; O' Doherty, M.J. [Clinical PET Centre, Guy' s and St Thomas' Hospitals, London (United Kingdom); Timothy, A.R.; Leslie, M.D.; Partridge, S.E. [Dept. of Clinical Oncology, Guy' s and St Thomas' Hospitals, London (United Kingdom); Huddart, R.A. [Dept. of Radiotherapy and Oncology, Royal Marsden, Surrey (United Kingdom)

    2000-05-01

    Testicular cancer is a rare tumour with the potential for cure at diagnosis. It is important, however, to identify those patients with metastases at presentation so as to ensure that the optimum treatment strategy is employed. Many criteria have been used to try to place patients into high- or low-risk groups, with variable success. Fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) has the potential to identify active disease and thereby influence further management. Here we report on a retrospective study of the use of FDG-PET in the detection of metastatic testicular carcinoma at diagnosis. Thirty-one patients [13 with seminoma and 18 with non-seminomatous germ cell tumours (13 teratomas, 5 mixed)] were staged by FDG-PET scanning. The imaging was performed using a Siemens ECAT 951 scanner. All results were assessed on the basis of histology or clinical follow-up. FDG-PET scan identified metastatic disease in ten and was negative in 16; there were no false-positives and five false-negatives. There were six patients in whom FDG-PET was negative and computed tomography was regarded as suspicious but follow-up was inconclusive. The positive predictive value was 100%. The negative predictive value was 76% or 91%, depending on whether the aforementioned six cases were regarded as true-negatives or false-negatives. It may be concluded that FDG-PET is capable of detecting metastatic disease at diagnosis that is not identified by other imaging techniques. These preliminary results are sufficient to suggest that a large prospective study should be performed to evaluate the role of FDG-PET in primary staging of disease. (orig.)

  9. Role of (18F) 2-fluoro-2-deoxyglucose positron emission tomography in upper gastrointestinal malignancies

    Institute of Scientific and Technical Information of China (English)

    Elizabeth C Smyth; Manish A Shah

    2011-01-01

    The role of whole-body FDG [(18F) 2-fluoro-2-deoxyglucose] positron emission tomography (PET) scanning as an imaging modality in the management of patients with malignancy has evolved enormously over the past two decades. FDG-PET has demonstrated significant efficacy in the staging, prognostication and detection of occult metastatic disease in malignancies of the gastrointestinal tract, in addition to assessment of the response to cytotoxic chemotherapy in a more timely manner than has traditionally been possible by more conventional imaging tools. The sensitivity and specificity of FDG-PET for the detection and staging of malignancy depend not only on the site and size of the primary tumor and metastases, but also on histological cell type, reflecting underlying disparities in glucose metabolism. The metabolic response to neo-adjuvant chemotherapy or to chemo-radiotherapy in cancers of the gastro-esophageal junction or stomach has been demonstrated in several prospective studies to correlate significantly with both the histological tumor response to treatment and with consequent improvements in overall survival. This may offer a future paradigm of personalized treatment based on the PET response to chemotherapy. FDG-PET has been less successful in efforts to screen for and detect recurrent upper gastrointestinal malignancies, and in the detection of low volume metastatic peritoneal disease. Efforts to improve the accuracy of PET include the use of novel radiotracers such as (18F) FLT (3-deoxy-3-fluorothymidine) or 11C-choline, or fusion PET-CT with concurrent high-resolution computed tomography. This review focuses on the role of FDG-PET scanning in staging and response assessment in malignancies of the upper gastrointestinal tract, specifically gastric, esophageal and pancreas carcinoma.

  10. Injectable silver nanosensors: in vivo dosimetry for external beam radiotherapy using positron emission tomography

    Science.gov (United States)

    Christensen, A. N.; Rydhög, J. S.; Søndergaard, R. V.; Andresen, T. L.; Holm, S.; Munck Af Rosenschöld, P.; Conradsen, K.; Jølck, R. I.

    2016-05-01

    Development of safe and efficient radiotherapy routines requires quantification of the delivered absorbed dose to the cancer tissue in individual patients. In vivo dosimetry can provide accurate information about the absorbed dose delivered during treatment. In the current study, a novel silver-nanosensor formulation based on poly(vinylpyrrolidinone)-coated silver nanoparticles formulated in a gelation matrix composed of sucrose acetate isobutyrate has been developed for use as an in vivo dosimeter for external beam radiotherapy. In situ photonuclear reactions trigger the formation of radioactive 106Ag, which enables post treatment verification of the delivered dose using positron emission tomography imaging. The silver-nanosensor was investigated in a tissue equivalent thorax phantom using clinical settings and workflow for both standard fractionated radiotherapy (2 Gy) and stereotactic radiotherapy (10- and 22 Gy) in a high-energy beam setting (18 MV). The developed silver-nanosensor provided high radiopacity on the planning CT-scans sufficient for patient positioning in image-guided radiotherapy and provided dosimetric information about the absorbed dose with a 10% and 8% standard deviation for the stereotactic regimens, 10 and 22 Gy, respectively.Development of safe and efficient radiotherapy routines requires quantification of the delivered absorbed dose to the cancer tissue in individual patients. In vivo dosimetry can provide accurate information about the absorbed dose delivered during treatment. In the current study, a novel silver-nanosensor formulation based on poly(vinylpyrrolidinone)-coated silver nanoparticles formulated in a gelation matrix composed of sucrose acetate isobutyrate has been developed for use as an in vivo dosimeter for external beam radiotherapy. In situ photonuclear reactions trigger the formation of radioactive 106Ag, which enables post treatment verification of the delivered dose using positron emission tomography imaging. The

  11. 18F-fluoro-deoxyglucose positron emission tomography/computed tomography scan findings in Rosai-Dorfman disease with IgG4-positive plasma cell infiltration mimicking breast malignancy: a case report and literature review

    Directory of Open Access Journals (Sweden)

    Fu Liping

    2012-11-01

    Full Text Available Abstract Introduction Rosai-Dorfman disease, also known as sinus histiocytosis with massive lymphadenopathy, is a rare benign disorder characterized histologically by lymphatic sinus dilatation due to histiocyte proliferation. Rosai-Dorfman disease accompanied by IgG4+ plasma cell infiltration is an even rarer situation. To the best of our knowledge, no imaging report of fluoro-deoxyglucose positron emission tomography/computed tomography findings of Rosai-Dorfman disease with IgG4+ plasma cell infiltration has been published, although a series of pathological research has focused on this phenomenon. Case presentation We reviewed the 18F-fluoro-deoxyglucose positron emission tomography/computed tomography scan of a 78-year-old Chinese woman with a solid mass that was found in her right breast during a health checkup. 18F-fluoro-deoxyglucose positron emission tomography/computed tomography showed a hypermetabolic nodule in her right breast and slightly heterogeneous increased fluoro-deoxyglucose uptake of the pulmonary nodules, which were histologically proven to be mammary Rosai-Dorfman disease with IgG4+ plasma cell infiltration and pulmonary amyloidosis, respectively. A literature review was performed to gather information on this rare disease process. Conclusions Although distinguishing benign lymphoplasmacytic proliferation from malignancy may be difficult with 18F-fluoro-deoxyglucose positron emission tomography/computed tomography in light of the pattern and intensity of fluoro-deoxyglucose uptake, our case highlights that whole-body positron emission tomography/computed tomography imaging not only can display the extent of the disease to help complete staging but also can provide functional information about disease activity to guide biopsy.

  12. Positron emission tomography in the management of cervix cancer patients; Tomographie par emission de positons dans la prise en charge des cancers du col de l'uterus

    Energy Technology Data Exchange (ETDEWEB)

    Bonardel, G.; Gontier, E.; Soret, M.; Dechaud, C.; Fayolle, M.; Foehrenbach, H. [Hopital d' Instruction des Armees du Val-de-Grace, Service de Medecine Nucleaire, 75 - Paris (France); Chargari, C.; Bauduceau, O. [Hopital d' Instruction des Armees du Val-de-Grace, Service de Radiotherapie, 75 - Paris (France)

    2009-10-15

    Since its introduction in clinical practice in the 1990 s, positron emission tomography (PET), usually with {sup 18}F-fluoro-2-deoxy-D-glucose ({sup 18}F-F.D.G.), has become an important imaging modality in patients with cancer. For cervix carcinoma, F.D.G.-PET is significantly more accurate than computed tomography (CT) and is recommended for loco-regional lymph node and extra pelvic staging. The metabolic dimension of the technique provides additional prognostic information. Ongoing studies now concentrate on more advanced clinical applications, such as the planning of radiotherapy, the response evaluation after the induction of therapy, the early detection of recurrence. Technical innovations, such as PET cameras with better spatial resolution and hybrid positron emission tomography/computed tomography (PET-CT), available now on the whole territory, provide both anatomic and metabolic information in the same procedure. From the point of view of biological metabolism, new radiopharmaceutical probes are being developed. Those hold promise for future refinements in this field. This article reviews the current applications of F.D.G.-PET in patients with cervix cancer. (authors)

  13. Effective dose to staff members in a positron emission tomography/CT facility using zirconium-89

    Science.gov (United States)

    2013-01-01

    Objective: Positron emission tomography (PET) using zirconium-89 (89Zr) is complicated by its complex decay scheme. In this study, we quantified the effective dose from 89Zr and compared it with fluorine-18 fludeoxyglucose (18F-FDG). Methods: Effective dose distribution in a PET/CT facility in Riyadh was calculated by Monte Carlo simulations using MCNPX. The positron bremsstrahlung, the annihilation photons, the delayed gammas from 89Zr and those emissions from 18F-FDG were modelled in the simulations but low-energy characteristic X-rays were ignored. Results: On the basis of injected activity, the dose from 89Zr was higher than that of 18F-FDG. However, the dose per scan from 89Zr became less than that from 18F-FDG near the patient, owing to the difference in injected activities. In the corridor and control rooms, the 89Zr dose was much higher than 18F-FDG, owing to the difference in attenuation by the shielding materials. Conclusion: The presence of the high-energy photons from 89Zr-labelled immuno-PET radiopharmaceuticals causes a significantly higher effective dose than 18F-FDG to the staff outside the patient room. Conversely, despite the low administered activity of 89Zr, it gives rise to a comparable or even lower dose than 18F-FDG to the staff near the patient. This interesting result raises apparently contradictory implications in the radiation protection considerations of a PET/CT facility. Advances in knowledge: To the best of our knowledge, radiation exposure to staff and public in the PET/CT unit using 89Zr has not been investigated. The ultimate output of this study will lead to the optimal design of the facility for routine use of 89Zr. PMID:23934963

  14. High-performance computing and networking as tools for accurate emission computed tomography reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Passeri, A. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy); Formiconi, A.R. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy); De Cristofaro, M.T.E.R. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy); Pupi, A. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy); Meldolesi, U. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy)

    1997-04-01

    It is well known that the quantitative potential of emission computed tomography (ECT) relies on the ability to compensate for resolution, attenuation and scatter effects. Reconstruction algorithms which are able to take these effects into account are highly demanding in terms of computing resources. The reported work aimed to investigate the use of a parallel high-performance computing platform for ECT reconstruction taking into account an accurate model of the acquisition of single-photon emission tomographic (SPET) data. An iterative algorithm with an accurate model of the variable system response was ported on the MIMD (Multiple Instruction Multiple Data) parallel architecture of a 64-node Cray T3D massively parallel computer. The system was organized to make it easily accessible even from low-cost PC-based workstations through standard TCP/IP networking. A complete brain study of 30 (64 x 64) slices could be reconstructed from a set of 90 (64 x 64) projections with ten iterations of the conjugate gradients algorithm in 9 s, corresponding to an actual speed-up factor of 135. This work demonstrated the possibility of exploiting remote high-performance computing and networking resources from hospital sites by means of low-cost workstations using standard communication protocols without particular problems for routine use. The achievable speed-up factors allow the assessment of the clinical benefit of advanced reconstruction techniques which require a heavy computational burden for the compensation effects such as variable spatial resolution, scatter and attenuation. The possibility of using the same software on the same hardware platform with data acquired in different laboratories with various kinds of SPET instrumentation is appealing for software quality control and for the evaluation of the clinical impact of the reconstruction methods. (orig.). With 4 figs., 1 tab.

  15. A Conway-Maxwell-Poisson (CMP) model to address data dispersion on positron emission tomography.

    Science.gov (United States)

    Santarelli, Maria Filomena; Della Latta, Daniele; Scipioni, Michele; Positano, Vincenzo; Landini, Luigi

    2016-10-01

    Positron emission tomography (PET) in medicine exploits the properties of positron-emitting unstable nuclei. The pairs of γ- rays emitted after annihilation are revealed by coincidence detectors and stored as projections in a sinogram. It is well known that radioactive decay follows a Poisson distribution; however, deviation from Poisson statistics occurs on PET projection data prior to reconstruction due to physical effects, measurement errors, correction of deadtime, scatter, and random coincidences. A model that describes the statistical behavior of measured and corrected PET data can aid in understanding the statistical nature of the data: it is a prerequisite to develop efficient reconstruction and processing methods and to reduce noise. The deviation from Poisson statistics in PET data could be described by the Conway-Maxwell-Poisson (CMP) distribution model, which is characterized by the centring parameter λ and the dispersion parameter ν, the latter quantifying the deviation from a Poisson distribution model. In particular, the parameter ν allows quantifying over-dispersion (νdispersion (ν>1) of data. A simple and efficient method for λ and ν parameters estimation is introduced and assessed using Monte Carlo simulation for a wide range of activity values. The application of the method to simulated and experimental PET phantom data demonstrated that the CMP distribution parameters could detect deviation from the Poisson distribution both in raw and corrected PET data. It may be usefully implemented in image reconstruction algorithms and quantitative PET data analysis, especially in low counting emission data, as in dynamic PET data, where the method demonstrated the best accuracy.

  16. Development of a dedicated positron emission tomography system for the detection and biopsy of breast cancer

    Science.gov (United States)

    Raylman, Raymond R.; Majewski, Stan; Kross, Brian; Popov, Vladimir; Proffitt, James; Smith, Mark F.; Weisenberger, Andrew G.; Wojcik, Randy

    2006-12-01

    Dedicated positron emission mammography breast imaging systems have shown great promise for the detection of small, radiotracer-avid lesions. Our group (a collaboration consisting of West Virginia University, Jefferson Lab and the University of Washington) is extending this work by developing a positron emission mammography-tomography (PEM-PET) system for imaging and biopsy of breast lesions. The system will have four planar detector heads that will rotate about the breast to acquire multi-view data suitable for tomographic reconstruction. Each detector head will consist of a 96×72 array of 2×2×15 mm 3 LYSO detector elements (pitch=2.1 mm) mounted on a 3×4 array of 5×5 cm 2 flat panel position-sensitive photomultiplier tubes. PEM-PET is expected to have approximately two-millimeter resolution and possess the ability to guide the needle biopsy of suspicious lesions seen on the PET images. Initial tests of the scintillator arrays yielded excellent results. Pixel maps for all four scintillator arrays demonstrated that separation of the LYSO elements was very good; all of the LYSO array elements were observed, even in areas between individual PSPMTs. System energy resolution was measured to be 25% FWHM at 511 keV. Future work includes the use of field programmable gate arrays (FPGAs) to replace the current VME-based data acquisition system, a PSPMT gain normalization procedure to help improve response uniformity and energy resolution, and the addition of an x-ray source and detector to produce multi-modality PEM-PET-CT images of the breast.

  17. Emission Computed Tomography: A New Technique for the Quantitative Physiologic Study of Brain and Heart in Vivo

    Science.gov (United States)

    Phelps, M. E.; Hoffman, E. J.; Huang, S. C.; Schelbert, H. R.; Kuhl, D. E.

    1978-01-01

    Emission computed tomography can provide a quantitative in vivo measurement of regional tissue radionuclide tracer concentrations. This facility when combined with physiologic models and radioactively labeled physiologic tracers that behave in a predictable manner allow measurement of a wide variety of physiologic variables. This integrated technique has been referred to as Physiologic Tomography (PT). PT requires labeled compounds which trace physiologic processes in a known and predictable manner, and physiologic models which are appropriately formulated and validated to derive physiologic variables from ECT data. In order to effectively achieve this goal, PT requires an ECT system that is capable of performing truly quantitative or analytical measurements of tissue tracer concentrations and which has been well characterized in terms of spatial resolution, sensitivity and signal to noise ratios in the tomographic image. This paper illustrates the capabilities of emission computed tomography and provides examples of physiologic tomography for the regional measurement of cerebral and myocardial metabolic rate for glucose, regional measurement of cerebral blood volume, gated cardiac blood pools and capillary perfusion in brain and heart. Studies on patients with stroke and myocardial ischemia are also presented.

  18. Cerebral hypometabolism in progressive supranuclear palsy studied with positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Foster, N.L.; Gilman, S.; Berent, S.; Morin, E.M.; Brown, M.B.; Koeppe, R.A.

    1988-09-01

    Progressive supranuclear palsy (PSP) is characterized by supranuclear palsy of gaze, axial dystonia, bradykinesia, rigidity, and a progressive dementia. Pathological changes in this disorder are generally restricted to subcortical structures, yet the type and range of cognitive deficits suggest the involvement of many cerebral regions. We examined the extent of functional impairment to cerebral cortical and subcortical structures as measured by the level of glucose metabolic activity at rest. Fourteen patients with PSP were compared to 21 normal volunteers of similar age using 18F-2-fluoro-2-deoxy-D-glucose and positron emission tomography. Glucose metabolism was reduced in the caudate nucleus, putamen, thalamus, pons, and cerebral cortex, but not in the cerebellum in the patients with PSP as compared to the normal subjects. Analysis of individual brain regions revealed significant declines in cerebral glucose utilization in most regions throughout the cerebral cortex, particularly those in the superior half of the frontal lobe. Declines in the most affected regions of cerebral cortex were greater than those in any single subcortical structure. Although using conventional neuropathological techniques the cerebral cortex appears to be unaffected in PSP, significant and pervasive functional impairments in both cortical and subcortical structures are present. These observations help to account for the constellation of cognitive symptoms in individual patients with PSP and the difficulty encountered in identifying a characteristic psychometric profile for this group of patients.

  19. Radiolabelled molecules for imaging the translocator protein (18 kDa) using positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Dolle, F.; Luus, C.; Reynolds, A.; Kassiou, M. [CEA, Institut d' Imagerie BioMedicale, Service Hospitalier Frederic Joliot, Orsay (France)

    2009-07-01

    The translocator protein (18 kDa) (TSPO), formerly known as the peripheral benzodiazepine receptor (PBR), was originally identified as an alternate binding site for the central benzodiazepine receptor (CBR) ligand, diazepam, in the periphery, but has now been distinguished as a novel site. The TSPO is ubiquitously expressed in peripheral tissues but only minimally in the healthy brain and increased levels of TSPO expression have been noted in neuro inflammatory conditions such as Alzheimer's disease, Parkinson's disease and stroke. This increase in TSPO expression has been reported to coincide with the process of micro-glial activation, whereby the brain's intrinsic immune system becomes active. Therefore, by using recently developed high affinity, selective TSPO ligands in conjunction with functional imaging modalities such as positron emission tomography (PET), it becomes possible to study the process of micro-glial activation in the living brain. A number of high affinity ligands, the majority of which are C, N-substituted acetamide derivatives, have been successfully radiolabelled and used in in vivo studies of the TSPO and the process of micro-glial activation. This review highlights recent achievements (up to December 2008) in the field of functional imaging of the TSPO as well as the radio-syntheses involved in such studies. (authors)

  20. Software development for dynamic position emission tomography: Dynamic image analysis (DIA) tool

    Energy Technology Data Exchange (ETDEWEB)

    Pyeon, Do Yeong; Jung, Young Jin [Dongseo University, Busan (Korea, Republic of); Kim, Jung Su [Dept. of Radilogical Science, Dongnam Health University, Suwon (Korea, Republic of)

    2016-09-15

    Positron Emission Tomography(PET) is nuclear medical tests which is a combination of several compounds with a radioactive isotope that can be injected into body to quantitatively measure the metabolic rate (in the body). Especially, Phenomena that increase (sing) glucose metabolism in cancer tissue using the 18F-FDG (Fluorodeoxyglucose) is utilized widely in cancer diagnosis. And then, Numerous studies have been reported that incidence seems high availability even in the modern diagnosis of dementia and Parkinson's (disease) in brain disease. When using a dynamic PET image including the time information in the static information that is provided for the diagnosis many can increase the accuracy of diagnosis. For this reason, clinical researchers getting great attention but, it is the lack of tools to conduct research. And, it interfered complex mathematical algorithm and programming skills for activation of research. In this study, in order to easy to use and enable research dPET, we developed the software based graphic user interface(GUI). In the future, by many clinical researcher using DIA-Tool is expected to be of great help to dPET research.

  1. Low background high efficiency radiocesium detection system based on positron emission tomography technology

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Seiichi; Ogata, Yoshimune [Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, 1-1-20 Daiko-Minami, Higashi-ku, Nagoya 461-8673 (Japan)

    2013-09-15

    After the 2011 nuclear power plant accident at Fukushima, radiocesium contamination in food became a serious concern in Japan. However, low background and high efficiency radiocesium detectors are expensive and huge, including semiconductor germanium detectors. To solve this problem, we developed a radiocesium detector by employing positron emission tomography (PET) technology. Because {sup 134}Cs emits two gamma photons (795 and 605 keV) within 5 ps, they can selectively be measured with coincidence. Such major environmental gamma photons as {sup 40}K (1.46 MeV) are single photon emitters and a coincidence measurement reduces the detection limit of radiocesium detectors. We arranged eight sets of Bi{sub 4}Ge{sub 3}O{sub 12} (BGO) scintillation detectors in double rings (four for each ring) and measured the coincidence between these detectors using PET data acquisition system. A 50 × 50 × 30 mm BGO was optically coupled to a 2 in. square photomultiplier tube (PMT). By measuring the coincidence, we eliminated most single gamma photons from the energy distribution and only detected those from {sup 134}Cs at an average efficiency of 12%. The minimum detectable concentration of the system for the 100 s acquisition time is less than half of the food monitor requirements in Japan (25 Bq/kg). These results show that the developed radiocesium detector based on PET technology is promising to detect low level radiocesium.

  2. A study of cerebral perfusion using single photon emission computed tomography in neonates with brain lesions

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, J.; Contantinesco, A.; Brunot, B.; Messer, J. (Hospital Universitaire de Strasbourg (France))

    1994-03-01

    In this study the authors used a single photon emission computed tomography technique (SPECT) with radiolabelled [sup 99m]Tc HMPAO to assess cerebral perfusion in newborn infants with documented cerebral lesions and to determine to what extent brain SPECT might be useful in the neonatal period. A total of 15 newborn infants with the following cerebral pathologies were enrolled: severe parietal bilateral periventricular leucomalacia; moderate parietal bilateral PVL; intraventricular haemorrhage grade II with unilateral parietal parenchymal extension; cerebral infarction in the zone of middle cerebral artery; and post-haemorrhagic hydrocephalus. Follow-up was available in all infants. Alterations in cerebral perfusion were seen in only 12 of 15 infants and at the location of severe PVL, PE and CI. It was noted that the regions of diminished perfusion extended beyond the apparent extent of cerebral pathology delineated by ultrasound or magnetic resonance imaging. Markedly diminished perfusion was seen in one infant with hydrocephalus, which recovered following placement of ventriculo-peritoneal shunt. Regarding outcome, SPECT data failed to provide additional information than that of neuroradiological investigations. It is concluded that the use of SPECT, under these conditions, to assess alteration of cerebral perfusion in the neonatal period will not provide any additional information than that of neuroradiological investigations. 17 refs., 3 figs., 1 tab.

  3. Modelling Random Coincidences in Positron Emission Tomography by Using Singles and Prompts: A Comparison Study

    Science.gov (United States)

    2016-01-01

    Random coincidences degrade the image in Positron Emission Tomography, PET. To compensate for their degradation effects, the rate of random coincidences should be estimated. Under certain circumstances, current estimation methods fail to provide accurate results. We propose a novel method, “Singles–Prompts” (SP), that includes the information conveyed by prompt coincidences and models the pile–up. The SP method has the same structure than the well-known “Singles Rate” (SR) approach. Hence, SP can straightforwardly replace SR. In this work, the SP method has been extensively assessed and compared to two conventional methods, SR and the delayed window (DW) method, in a preclinical PET scenario using Monte–Carlo simulations. SP offers accurate estimates for the randoms rates, while SR and DW tend to overestimate the rates (∼10%, and 5%, respectively). With pile-up, the SP method is more robust than SR (but less than DW). At the image level, the contrast is overestimated in SR-corrected images, +16%, while SP produces the correct value. Spill–over is slightly reduced using SP instead of SR. The DW images values are similar to those of SP except for low-statistic scenarios, where DW behaves as if randoms were not compensated for. In particular, the contrast is reduced, −16%. In general, the better estimations of SP translate into better image quality. PMID:27603143

  4. Photo-detectors for time of flight positron emission tomography (ToF-PET).

    Science.gov (United States)

    Spanoudaki, Virginia Ch; Levin, Craig S

    2010-01-01

    We present the most recent advances in photo-detector design employed in time of flight positron emission tomography (ToF-PET). PET is a molecular imaging modality that collects pairs of coincident (temporally correlated) annihilation photons emitted from the patient body. The annihilation photon detector typically comprises a scintillation crystal coupled to a fast photo-detector. ToF information provides better localization of the annihilation event along the line formed by each detector pair, resulting in an overall improvement in signal to noise ratio (SNR) of the reconstructed image. Apart from the demand for high luminosity and fast decay time of the scintillation crystal, proper design and selection of the photo-detector and methods for arrival time pick-off are a prerequisite for achieving excellent time resolution required for ToF-PET. We review the two types of photo-detectors used in ToF-PET: photomultiplier tubes (PMTs) and silicon photo-multipliers (SiPMs) with a special focus on SiPMs.

  5. Photo-Detectors for Time of Flight Positron Emission Tomography (ToF-PET

    Directory of Open Access Journals (Sweden)

    Craig S. Levin

    2010-11-01

    Full Text Available We present the most recent advances in photo-detector design employed in time of flight positron emission tomography (ToF-PET. PET is a molecular imaging modality that collects pairs of coincident (temporally correlated annihilation photons emitted from the patient body. The annihilation photon detector typically comprises a scintillation crystal coupled to a fast photo-detector. ToF information provides better localization of the annihilation event along the line formed by each detector pair, resulting in an overall improvement in signal to noise ratio (SNR of the reconstructed image. Apart from the demand for high luminosity and fast decay time of the scintillation crystal, proper design and selection of the photo-detector and methods for arrival time pick-off are a prerequisite for achieving excellent time resolution required for ToF-PET. We review the two types of photo-detectors used in ToF-PET: photomultiplier tubes (PMTs and silicon photo-multipliers (SiPMs with a special focus on SiPMs.

  6. A new mechanism of ionizing radiation detection for positron emission tomography: modulation of optical properties

    Science.gov (United States)

    Tao, Li; Daghighian, Henry M.; Levin, Craig S.

    2016-10-01

    Using conventional scintillation detection, the fundamental limit in positron emission tomography (PET) annihilation photon pair coincidence time resolution is strongly dependent on the inherent temporal variances generated during the scintillation process, yielding an intrinsic physical limit of around 100 ps. On the other hand, modulation mechanisms of a material's optical properties as exploited in the optical telecommunications industry can be orders of magnitude faster. In this paper we borrow from the concept of optics pump-probe measurement to study whether ionizing radiation can also produce fast modulations of optical properties, which can be utilized as a novel method for radiation detection. We show that a refractive index modulation of approximately 5x10-6 is induced by interactions in a cadmium telluride (CdTe) crystal from a 511 keV photon source. Furthermore, using additional radionuclide sources, we show that the amplitude of the optical modulation signal varies linearly with both the radiation source flux rate and average photon energy.

  7. Dynamic positron emission tomography image restoration via a kinetics-induced bilateral filter.

    Directory of Open Access Journals (Sweden)

    Zhaoying Bian

    Full Text Available Dynamic positron emission tomography (PET imaging is a powerful tool that provides useful quantitative information on physiological and biochemical processes. However, low signal-to-noise ratio in short dynamic frames makes accurate kinetic parameter estimation from noisy voxel-wise time activity curves (TAC a challenging task. To address this problem, several spatial filters have been investigated to reduce the noise of each frame with noticeable gains. These filters include the Gaussian filter, bilateral filter, and wavelet-based filter. These filters usually consider only the local properties of each frame without exploring potential kinetic information from entire frames. Thus, in this work, to improve PET parametric imaging accuracy, we present a kinetics-induced bilateral filter (KIBF to reduce the noise of dynamic image frames by incorporating the similarity between the voxel-wise TACs using the framework of bilateral filter. The aim of the proposed KIBF algorithm is to reduce the noise in homogeneous areas while preserving the distinct kinetics of regions of interest. Experimental results on digital brain phantom and in vivo rat study with typical (18F-FDG kinetics have shown that the present KIBF algorithm can achieve notable gains over other existing algorithms in terms of quantitative accuracy measures and visual inspection.

  8. Detection of neuronal damage in degenerative brain disease with cobalt-55 and positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Jansen, H.M.L.; Pruim, J.; Paans, A.M.J. [Univ. Hospital Groningen (Netherlands)] [and others

    1994-05-01

    We suggest Cobalt-55 (Co) as a Calcium (Ca)-marker to visualize Ca transport across the neuronal membrane. Elevation of intracellular Ca is closely linked with the process of neuronal cell-decay. Co-uptake is correlated with Ca-accumulation through divalent cation-permeable kainate (KA)-activated receptor-operated channels in the neuronal membrane. This hypothesis was studied with position emission tomography (PET) both in patients with a ischemic cerebro-vascular accident (CVA) and in patients with relapsing progressive multiple sclerosis (MS). Co-PET studies were performed in a dynamic mode (6 frames of 10 minutes) 20-25 hours after iv.-administration of 1-2 mCi Co. Regional specific accumulation irrespective of blood brain barrier (BBB) integrity in the (clinically appropriate) affected cerebral region could be demonstrated in CVA-patients, thus suggesting neuronal decay in (the early phase of) infarction. In MS, inhomogeneous cerebral distribution of Co was detected, in contrast to healthy volunteers. This suggests focal accumulation of Co in multiple spots of neuronal decay, possibly related to MS-lesions on MRI. In conclusion, Co-PET may prove to be a valuable tool for the early detection of neuronal decay not only in CVA and MS, but in other brain-pathology as well. The usefulness of Co-PET in imaging brain-tumors and myocardial ischemia has already been established.

  9. List-mode image reconstruction for positron emission tomography using tetrahedral voxels

    Science.gov (United States)

    Gillam, John E.; Angelis, Georgios I.; Meikle, Steven R.

    2016-09-01

    Image space decomposition based on tetrahedral voxels are interesting candidates for use in emission tomography. Tetrahedral voxels provide many of the advantages of point clouds with irregular spacing, such as being intrinsically multi-resolution, yet they also serve as a volumetric partition of the image space and so are comparable to more standard cubic voxels. Additionally, non-rigid displacement fields can be applied to the tetrahedral mesh in a straight-forward manner. So far studies incorporating tetrahedral decomposition of the image space have concentrated on pre-calculated, node-based, system matrix elements which reduces the flexibility of the tetrahedral approach and the capacity to accurately define regions of interest. Here, a list-mode on-the-fly calculation of the system matrix elements is described using a tetrahedral decomposition of the image space and volumetric elements—voxels. The algorithm is demonstrated in the context of awake animal PET which may require both rigid and non-rigid motion compensation, as well as quantification within small regions of the brain. This approach allows accurate, event based, motion compensation including non-rigid deformations.

  10. Towards an optimal reference region in single-photon emission tomography difference images in epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Boussion, N.; Ryvlin, P.; Isnard, J.; Mauguiere, F. [Neurologie Fonctionnelle et Epilepsie, Hopital Neurologique, Lyon (France); Houzard, C. [Centre de Medecine Nucleaire, Hopital Neuro-Cardiologique, Lyon (France); Cinotti, L. [Neurologie Fonctionnelle et Epilepsie, Hopital Neurologique, Lyon (France); Centre de Medecine Nucleaire, Hopital Neuro-Cardiologique, Lyon (France); CERMEP, Hopital Neuro-Cardiologique, Lyon (France)

    2000-02-01

    There is marked variability in the cerebral blood flow (CBF) between the ictal and interictal state in epilepsy, and it would therefore be desirable to increase the reliability of ictal/interictal single-photon emission tomography (SPET) difference images. We aimed to improve the step of quantitative normalization of images by finding the best possible reference region. In 16 patients (11 with lateralization of the epileptogenic focus, five with bilateral foci) both ictal and inter-ictal SPET scans were performed after injection of technetium-99m labelled tracer. Then, each region among a selected set (brain+cerebellum, brain, cerebellum, hemispheres, and for patients with an expected lateralization, cortical lobe containing the focus and symmetrical contralateral lobe) was investigated by comparison of the regional ictal/inter-ictal variance in counts. Among patients with a suspected lateralized focus, the distribution of CBF in the contralateral cortical lobe appeared to vary less between ictal and inter-ictal states than in other investigated areas. As a consequence, this latter region constitutes the best choice as a reference region. For patients with bilateral foci, the cerebellum appears to be a good compromise even though it presents with significant CBF changes. (orig.)

  11. Monitoring of patients treated with particle therapy using positron-emission-tomography (PET: the MIRANDA study

    Directory of Open Access Journals (Sweden)

    Combs Stephanie E

    2012-04-01

    Full Text Available Abstract Background The purpose of this clinical study is to investigate the clinical feasibility and effectiveness of offline Positron-Emission-Tomography (PET quality assurance for promoting the accuracy of proton and carbon ion beam therapy. Methods/Design A total of 240 patients will be recruited, evenly sampled among different analysis groups including tumors of the brain, skull base, head and neck region, upper gastrointestinal tract including the liver, lower gastrointestinal tract, prostate and pelvic region. From the comparison of the measured activity with the planned dose and its corresponding simulated activity distribution, conclusions on the delivered treatment will be inferred and, in case of significant deviations, correction strategies will be elaborated. Discussion The investigated patients are expected to benefit from this study, since in case of detected deviations between planned and actual treatment delivery a proper intervention (e.g., correction could be performed in a subsequent irradiation fraction. In this way, an overall better treatment could be achieved than without any in-vivo verification. Moreover, site-specific patient-population information on the precision of the ion range at HIT might enable improvement of the CT-range calibration curve as well as safe reduction of the treatment margins to promote enhanced treatment plan conformality and dose escalation for full clinical exploitation of the promises of ion beam therapy. Trial Registration NCT01528670

  12. The value of positron emission tomography in patients with non-small cell lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kee, Frank [Centre for Public Health, Queen' s University Belfast, Mulhouse Building, Royal Victoria Hospital Site, Grosvenor Road, Belfast BT12 6BJ, Northern Ireland (United Kingdom)], E-mail: f.kee@qub.ac.uk; Erridge, Sara [Edinburgh Cancer Centre, University of Edinburgh, Crewe Road South, Edinburgh EH4 2XU, Scotland (United Kingdom); Bradbury, Ian [Frontier Science (Scotland) Ltd., Grampian View, Kincraig, Inverness-shire PH21 1NA, Scotland (United Kingdom); Cairns, Karen [School of Maths and Physics, Queen' s University Belfast, David Bates Building, University Road, Belfast BT7 1NN, Northern Ireland (United Kingdom)

    2010-01-15

    Background: Pre-operative assessment of non-small cell lung cancer (NSCLC) is a major application of positron emission tomography (FDG-PET). Despite substantial evidence of diagnostic accuracy, relatively little attention has been paid to its effects on patient outcomes. This paper addresses this by extending an existing decision model to include patient-elicited utilities. Patients and methods: A decision-tree model of the effect of FDG-PET on pre-operative staging was converted to a Markov model. Utilities for futile and appropriate thoracotomy were elicited from 75 patients undergoing staging investigation for NSCLC. The decision model was then used to estimate the expected value of perfect information (EVPI) associated with three sources of uncertainty-the accuracy of PET, the accuracy of CT and the patient related utility of a futile thoracotomy. Results: The model confirmed the apparent cost-effectiveness of FDG-PET and indicated that the EVPI associated with the utility of futile thoracotomy considerably exceeds that associated with measures of accuracy. Conclusion: The study highlights the importance of patient related utilities in assessing the cost-effectiveness of diagnostic technologies. In the specific case of PET for pre-operative staging of NSCLC, future research effort should focus on such elicitation, rather than further refinement of accuracy estimates.

  13. INSIDE in-beam positron emission tomography system for particle range monitoring in hadrontherapy.

    Science.gov (United States)

    Bisogni, Maria Giuseppina; Attili, Andrea; Battistoni, Giuseppe; Belcari, Nicola; Camarlinghi, Niccolo'; Cerello, Piergiorgio; Coli, Silvia; Del Guerra, Alberto; Ferrari, Alfredo; Ferrero, Veronica; Fiorina, Elisa; Giraudo, Giuseppe; Kostara, Eleftheria; Morrocchi, Matteo; Pennazio, Francesco; Peroni, Cristiana; Piliero, Maria Antonietta; Pirrone, Giovanni; Rivetti, Angelo; Rolo, Manuel D; Rosso, Valeria; Sala, Paola; Sportelli, Giancarlo; Wheadon, Richard

    2017-01-01

    The quality assurance of particle therapy treatment is a fundamental issue that can be addressed by developing reliable monitoring techniques and indicators of the treatment plan correctness. Among the available imaging techniques, positron emission tomography (PET) has long been investigated and then clinically applied to proton and carbon beams. In 2013, the Innovative Solutions for Dosimetry in Hadrontherapy (INSIDE) collaboration proposed an innovative bimodal imaging concept that combines an in-beam PET scanner with a tracking system for charged particle imaging. This paper presents the general architecture of the INSIDE project but focuses on the in-beam PET scanner that has been designed to reconstruct the particles range with millimetric resolution within a fraction of the dose delivered in a treatment of head and neck tumors. The in-beam PET scanner has been recently installed at the Italian National Center of Oncologic Hadrontherapy (CNAO) in Pavia, Italy, and the commissioning phase has just started. The results of the first beam test with clinical proton beams on phantoms clearly show the capability of the in-beam PET to operate during the irradiation delivery and to reconstruct on-line the beam-induced activity map. The accuracy in the activity distal fall-off determination is millimetric for therapeutic doses.

  14. Neural correlates of sensorimotor gating: A metabolic positron emission tomography study in awake rats

    Directory of Open Access Journals (Sweden)

    Cathrin eRohleder

    2014-05-01

    Full Text Available Impaired sensorimotor gating occurs in neuropsychiatric disorders such as schizophrenia and can be measured using the prepulse inhibition (PPI paradigm of the acoustic startle response. This assay is frequently used to validate animal models of neuropsychiatric disorders and to explore the therapeutic potential of new drugs. The underlying neural network of PPI has been extensively studied with invasive methods and genetic modifications. However, its relevance for healthy untreated animals and the functional interplay between startle- and PPI-related areas during a PPI session is so far unknown. Therefore, we studied awake rats in a PPI paradigm, startle control and background noise control, combined with behavioral [18F]fluoro-2-deoxyglucose positron emission tomography (FDG-PET. Subtractive analyses between conditions were used to identify brain regions involved in startle and PPI processing in well-hearing Black hooded rats. For correlative analysis with regard to the amount of PPI we also included hearing-impaired Lister hooded rats that startled more often, because their hearing threshold was just below the lowest prepulses. Metabolic imaging showed that the brain areas proposed for startle and PPI mediation are active during PPI paradigms in healthy untreated rats. More importantly, we show for the first time that the whole PPI modulation network is active during passive PPI sessions, where no selective attention to prepulse or startle stimulus is required. We conclude that this reflects ongoing monitoring of stimulus significance and constant adjustment of sensorimotor gating.

  15. Emission line tomography of the short period cataclysmic variables CC Scl and V2051 Oph

    CERN Document Server

    Longa-Peña, P; Marsh, T

    2014-01-01

    We present time-series spectroscopy of two short period cataclysmic variables, CC Scl and V2051 Oph, to test the efficiency of Doppler tomography-based methods in constraining orbital parameters of evolved cataclysmic variables. We find that the Ca~II triplet lines offer superior diagnostics, revealing emission components from the mass donors and sharp images of the accretion discs. Furthermore, we use Monte-Carlo methods to estimate the uncertainties from ensembles of Doppler maps. We compare our new methods against traditional radial velocity methods and show that they offer a valid route towards system parameter determination. Our analysis of CC Scl suggests a low mass ratio of $q=0.08\\pm0.03$ with a primary velocity of $K_1=37\\pm14$ km/s. This mass ratio is in between the pre- and post-period minimum status, however our $K_1$ solution favours a post-period minimum system. Our derived parameters for V2051 Oph ($q= 0.16\\pm 0.03$, $K_1=97\\pm10$ km/s) are in agreement with the eclipse solution ($q=0.19\\pm0.03...

  16. Preclinical positron emission tomography scanner based on a monolithic annulus of scintillator: initial design study.

    Science.gov (United States)

    Stolin, Alexander V; Martone, Peter F; Jaliparthi, Gangadhar; Raylman, Raymond R

    2017-01-01

    Positron emission tomography (PET) scanners designed for imaging of small animals have transformed translational research by reducing the necessity to invasively monitor physiology and disease progression. Virtually all of these scanners are based on the use of pixelated detector modules arranged in rings. This design, while generally successful, has some limitations. Specifically, use of discrete detector modules to construct PET scanners reduces detection sensitivity and can introduce artifacts in reconstructed images, requiring the use of correction methods. To address these challenges, and facilitate measurement of photon depth-of-interaction in the detector, we investigated a small animal PET scanner (called AnnPET) based on a monolithic annulus of scintillator. The scanner was created by placing 12 flat facets around the outer surface of the scintillator to accommodate placement of silicon photomultiplier arrays. Its performance characteristics were explored using Monte Carlo simulations and sections of the NEMA NU4-2008 protocol. Results from this study revealed that AnnPET's reconstructed spatial resolution is predicted to be [Formula: see text] full width at half maximum in the radial, tangential, and axial directions. Peak detection sensitivity is predicted to be 10.1%. Images of simulated phantoms (mini-hot rod and mouse whole body) yielded promising results, indicating the potential of this system for enhancing PET imaging of small animals.

  17. Novel electro-optical coupling technique for magnetic resonance-compatible positron emission tomography detectors.

    Science.gov (United States)

    Olcott, Peter D; Peng, Hao; Levin, Craig S

    2009-01-01

    A new magnetic resonance imaging (MRI)-compatible positron emission tomography (PET) detector design is being developed that uses electro-optical coupling to bring the amplitude and arrival time information of high-speed PET detector scintillation pulses out of an MRI system. The electro-optical coupling technology consists of a magnetically insensitive photodetector output signal connected to a nonmagnetic vertical cavity surface emitting laser (VCSEL) diode that is coupled to a multimode optical fiber. This scheme essentially acts as an optical wire with no influence on the MRI system. To test the feasibility of this approach, a lutetium-yttrium oxyorthosilicate crystal coupled to a single pixel of a solid-state photomultiplier array was placed in coincidence with a lutetium oxyorthosilicate crystal coupled to a fast photomultiplier tube with both the new nonmagnetic VCSEL coupling and the standard coaxial cable signal transmission scheme. No significant change was observed in 511 keV photopeak energy resolution and coincidence time resolution. This electro-optical coupling technology enables an MRI-compatible PET block detector to have a reduced electromagnetic footprint compared with the signal transmission schemes deployed in the current MRI/PET designs.

  18. Novel Electro-Optical Coupling Technique for Magnetic Resonance-Compatible Positron Emission Tomography Detectors

    Directory of Open Access Journals (Sweden)

    Peter D. Olcott

    2009-03-01

    Full Text Available A new magnetic resonance imaging (MRI-compatible positron emission tomography (PET detector design is being developed that uses electro-optical coupling to bring the amplitude and arrival time information of high-speed PET detector scintillation pulses out of an MRI system. The electro-optical coupling technology consists of a magnetically insensitive photodetector output signal connected to a nonmagnetic vertical cavity surface emitting laser (VCSEL diode that is coupled to a multimode optical fiber. This scheme essentially acts as an optical wire with no influence on the MRI system. To test the feasibility of this approach, a lutetium-yttrium oxyorthosilicate crystal coupled to a single pixel of a solid-state photomultiplier array was placed in coincidence with a lutetium oxyorthosilicate crystal coupled to a fast photomultiplier tube with both the new nonmagnetic VCSEL coupling and the standard coaxial cable signal transmission scheme. No significant change was observed in 511 keV photopeak energy resolution and coincidence time resolution. This electro-optical coupling technology enables an MRI-compatible PET block detector to have a reduced electromagnetic footprint compared with the signal transmission schemes deployed in the current MRI/PET designs.

  19. Effect of Harderian adenectomy on the statistical analyses of mouse brain imaging using positron emission tomography.

    Science.gov (United States)

    Kim, Minsoo; Woo, Sang-Keun; Yu, Jung Woo; Lee, Yong Jin; Kim, Kyeong Min; Kang, Joo Hyun; Eom, Kidong; Nahm, Sang-Soep

    2014-01-01

    Positron emission tomography (PET) using 2-deoxy-2-[(18)F] fluoro-D-glucose (FDG) as a radioactive tracer is a useful technique for in vivo brain imaging. However, the anatomical and physiological features of the Harderian gland limit the use of FDG-PET imaging in the mouse brain. The gland shows strong FDG uptake, which in turn results in distorted PET images of the frontal brain region. The purpose of this study was to determine if a simple surgical procedure to remove the Harderian gland prior to PET imaging of mouse brains could reduce or eliminate FDG uptake. Measurement of FDG uptake in unilaterally adenectomized mice showed that the radioactive signal emitted from the intact Harderian gland distorts frontal brain region images. Spatial parametric measurement analysis demonstrated that the presence of the Harderian gland could prevent accurate assessment of brain PET imaging. Bilateral Harderian adenectomy efficiently eliminated unwanted radioactive signal spillover into the frontal brain region beginning on postoperative Day 10. Harderian adenectomy did not cause any post-operative complications during the experimental period. These findings demonstrate the benefits of performing a Harderian adenectomy prior to PET imaging of mouse brains.

  20. Molecular imaging of neuroinflammation in preclinical rodent models using positron emission tomography.

    Science.gov (United States)

    Gargiulo, Sara; Coda, Anna R; Panico, Mariarosaria; Gramanzini, Matteo; Moresco, Rosa M; Chalon, Sylvie; Pappatà, Sabina

    2017-03-01

    Neuroinflammation (NI) is an adaptive response to different noxious stimuli, involving microglia, astrocytes and peripheral immune cells. NI is a hallmark of several acute and chronic diseases of central nervous system (CNS) and contributes to both damage and repair of CNS tissue. Interventional or genetically modified rodent models mimicking human neuropathologies may provide valuable insights on basic mechanisms of NI, but also for improving the development of new diagnostic and therapeutic strategies. Preclinical positron emission tomography (PET) allows to investigate noninvasively the inflammatory response in CNS of rodent models at a molecular level, validating innovative probes for early diagnosis, and characterizing the time course of neuroinflammatory changes and their relationship with disease progression, as well as the effects of experimental treatments with high translational potential. In particular, recent efforts of preclinical PET field are intended to develop specific and selective radiotracers that target the activation of innate immune system in CNS. Here, we have reviewed the state of art for PET in relevant rodent models of acute and chronic neuropathologies associated with NI, with particular regard on imaging of activated microglia and astrocytes.

  1. Metabolizer in vivo of fullerenes and metallofullerenes by positron emission tomography

    Science.gov (United States)

    Li, Juan; Yang, Wenjiang; Cui, Rongli; Wang, Dongliang; Chang, Yanan; Gu, Weihong; Yin, Wenyan; Bai, Xue; Chen, Kui; Xia, Lin; Geng, Huan; Xing, Gengmei

    2016-04-01

    Fullerenes (C60) and metallofullerenes (Gd@C82) have similar chemical structure, but the bio-effects of both fullerene-based materials are distinct in vivo. Tracking organic carbon-based materials such as C60 and Gd@C82 is difficult in vivo due to the high content of carbon element in the living tissues themselves. In this study, the biodistribution and metabolism of fullerenes (C60 and Gd@C82) radiolabeled with 64Cu were observed by positron emission tomography (PET). 64Cu-C60 and 64Cu-Gd@C82 were prepared using 1, 4, 7, 10-tetrakis (carbamoylmethyl)-1, 4, 7, 10-tetra-azacyclodo-decanes grafted on carbon cages as a chelator for 64Cu, and were obtained rapidly with high radiochemical yield (≥90%). The new radio-conjugates were evaluated in vivo in the normal mouse model and tissue distribution by small animal PET/CT imaging and histology was carried out. The PET imaging, the biodistribution and the excretion of C60 and Gd@C82 indicated that C60 samples have higher blood retention and lower renal clearance than the Gd@C82 samples in vivo and suggested that the differences in metabolism and distribution in vivo were caused by the structural differences of the groups on the fullerene cages though there is chemical similarity between C60 and Gd@C82.

  2. Imaging of lesions in the posterior cranial fossa using single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, Michiro; Uesugi, Yasuo; Higashikawa, Masahiko; Ochi, Mari; Makimoto, Kazuo; Takahashi, Hiroaki; Shin, Akinori; Utsunomiya, Keita; Akagi, Hiroaki

    1988-10-01

    Lesions in the posterior cranial fossa were visualized by single photon emission computed tomography (SPECT) with /sup 123/I-IMP (N-isopropyl-p-/sup 123/I-iodoamphetamine) and /sup 99m/Tc-HM-PAO (/sup 99m/Tc-hexametylpropyleneamine oxime). It is generally held that these radiopharmaceuticals penetrate the walls of cerebral blood vessels and that their accumulations in the brain tissue may reflect the cerebral blood flow. Six patients with lesions in the central nervous system all showed wider areas of abnormality in SPECT than in X-ray CT, indicating a larger lesion of blood flow disturbance. In the next series of 11 patients with vertigo or dizziness of unknown etiology, eight had abnormal findings in the scan with /sup 123/I-IMP as did four of the nine in the scan with /sup 99m/Tc-HM-PAO. Thus, most patients with dizziness of unknown etiology may have some vertebral blood flow disorder, which in some cases is not clearly diagnosed by conventional vestibular examinations or even by X-ray CT scan. The accuracy of the diagnostic measures for otoneurological problems awaits further studies of their sensitivity and specificity.

  3. Positron Emission Tomography Reveals Abnormal Topological Organization in Functional Brain Network in Diabetic Patients

    Directory of Open Access Journals (Sweden)

    Qiu eXiangzhe

    2016-05-01

    Full Text Available Recent studies have demonstrated alterations in the topological organization of structural brain networks in diabetes mellitus (DM. However, the DM-related changes in the topological properties in functional brain networks are almost unexplored so far. We therefore used fluoro-D-glucose positron emission tomography (FDG-PET data to construct functional brain networks of 73 DM patients and 91 sex- and age-matched normal controls (NCs, followed by a graph theoretical analysis. We found that both DM patients and NCs had a small-world topology in functional brain network. In comparison to the NC group, the DM group was found to have significantly lower small-world index, lower normalized clustering coefficients and higher normalized shortest path length. Moreover, for diabetic patients, the nodal centrality was significantly reduced in the right rectus, the right cuneus, the left middle occipital gyrus, and the left postcentral gyrus, and it was significantly increased in the orbitofrontal region of the left middle frontal gyrus, the left olfactory region, and the right paracentral lobule. Our results demonstrated that the diabetic brain was associated with disrupted topological organization in the functional PET network, thus providing the functional evidence for the abnormalities of brain networks in DM.

  4. Development of analog solid-state photo-detectors for Positron Emission Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Bisogni, Maria Giuseppina, E-mail: giuseppina.bisogni@pi.infn.it; Morrocchi, Matteo

    2016-02-11

    Solid-state photo-detectors are one of the main innovations of past century in the field of sensors. First produced in the early forties with the invention of the p–n junction in silicon and the study of its optical properties, photo-detectors received a major boost in the sixties when the p-i-n (PIN) photodiode was developed and successfully used in several applications. The development of devices with internal gain, avalanche photodiodes (APD) first and then Geiger-mode avalanche photodiodes, named single photon avalanche diode (SPAD), leads to a substantial improvement in sensitivity and allowed single photon detection. Later on, thousands of SPADs have been assembled in arrays of few millimeters squared (named SiPM, silicon photo-multiplier) with single photon resolution. The high internal gain of SiPMs, together with other features peculiar of the silicon technology like compactness, speed and compatibility with magnetic fields, promoted SiPMs as the principal photo-detector competitor of photomultipliers in many applications from radiation detection to medical imaging. This paper provides a review of the properties of analog solid-state photo-detectors. Particular emphasis is given to latest advances on Positron Emission Tomography instrumentation boosted by the adoption of the silicon photo-detectors as an alternative to photomultiplier tubes (PMTs). Special attention is dedicated to the SiPMs, which are playing a key role in the development of innovative scanners.

  5. Optimized separation procedure for production of no-carrier-added radiomanganese for positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Buchholz, Martin; Spahn, Ingo; Coenen, Heinz H. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Neurowissenschaften und Medizin (INM), Nuklearchemie (INM-5)

    2015-07-01

    The {sup nat}Cr(p,xn)-process is a very efficient route for production of {sup 52g}Mn(T{sub 1/2} = 5.59 d). Based on measurements of distribution coefficients with different media and ion-exchange resins, an optimized chromatographic separation of radiomanganese from {sup nat}Cr with the resin Amberlite CG400 was developed. With this system {sup nat}Cr is eluted first with an acetic acid/methanol 1:1 mixture at room temperature and {sup 52g}Mn thereafter with 3 M HCl at 50 C. Within a separation time of 4 h the method yielded 99.5% of the n.c.a. {sup 52g}Mn in 2-3 mL of 3 M HCl. An ICP-MS analysis revealed a chromium impurity of 0.07 mg (0.014%) in the n.c.a. {sup 52g}Mn solution, making this separation method suitable for the production of {sup 52g}Mn for medical applications like positron emission tomography (PET).

  6. A behavioral and micro positron emission tomography imaging study in a rat model of hypothyroidism.

    Science.gov (United States)

    Yu, Jing; Tang, Yi-Yuang; Feng, Hong-Bo; Cheng, Xiao-Xin

    2014-09-01

    Hypothyroidism leads to somatic, neuropsychological, and psychiatric changes that are similar to depression. The mechanisms underlying the behavioral abnormalities in adult onset hypothyroidism remain ambiguous. Hypothyroidism was induced in adult male Wistar rats by the maintenance of 0.05% propylthiouracil (PTU) in drinking water for 5 weeks (hypothyroid group; HP group); control rats (CON group) received an equivalent amount of water. The open field and sucrose preference tests were employed, and the link between behavioral changes and brain glucose metabolism was evaluated using micro positron emission tomography imaging. The open field test revealed slightly decreased locomotor activity and significantly reduced rearing and defecation in the hypothyroid group. Hypothyroid rats were also characterized by decreased body weight, sucrose preference, and relative sucrose intake compared to control rats. Hypothyroidism induced reduced brain glucose metabolism in the bilateral motor cortex, the caudate putamen, the cortex cingulate, the nucleus accumbens, and the frontal association cortex. A decreased sucrose preference was positively correlated with metabolic glucose changes in the caudate putamen and the nucleus accumbens. The results indicate that the activity pattern in adult onset hypothyroidism is different from the activity pattern when hypothyroidism is induced in the developmental period of the central nervous system. Decreased sucrose preference in hypothyroid rats may be attributed to anhedonia. Furthermore, these findings suggest there may be a common mechanism underlying adult onset hypothyroidism and depression.

  7. Kinetic analysis of [11C]vorozole binding in the human brain with positron emission tomography.

    Science.gov (United States)

    Logan, Jean; Kim, Sung Won; Pareto, Deborah; Telang, Frank; Wang, Gene-Jack; Fowler, Joanna S; Biegon, Anat

    2014-01-01

    Using positron emission tomography, we investigated the kinetics of [11C]vorozole ([11C]VOR), a radiotracer for the enzyme aromatase that catalyzes the last step in estrogen biosynthesis. Six subjects were scanned under baseline conditions followed by retest 2 weeks later. The retest was followed by a blocking study with 2.5 mg of the aromatase inhibitor letrozole. The binding potential (BP(A)ND) was estimated from a Lassen plot using the total tissue distribution volume (VT) for baseline and blocked. for the thalamus was found to be 15 times higher than that for the cerebellum. From the letrozole studies, we found that [11C]VOR exhibits a slow binding compartment (small k4) that has a nonspecific and a blockable component. Because of the sensitivity of VT to variations in k4, a common value was used for the four highest binding regions. We also considered the tissue uptake to plasma ratio for 60 to 90 minutes as an outcome measure. Using the ratio method, the difference between the highest and lowest was 2.4 compared to 3.5 for the VT. The ratio method underestimates the high regions but is less variable and may be more suitable for patient studies. Because of its kinetics and distribution, this tracer is not a candidate for a bolus infusion or reference tissue methods.

  8. Positron emission tomography molecular imaging of dopaminergic system in drug addiction.

    Science.gov (United States)

    Hou, Haifeng; Tian, Mei; Zhang, Hong

    2012-05-01

    Dopamine (DA) is involved in drug reinforcement, but its role in drug addiction remains unclear. Positron emission tomography (PET) is the first technology used for the direct measurement of components of the dopaminergic system in the living human brain. In this article, we reviewed the major findings of PET imaging studies on the involvement of DA in drug addiction, especially in heroin addiction. Furthermore, we summarized PET radiotracers that have been used to study the role of DA in drug addiction. To investigate presynaptic function in drug addiction, PET tracers have been developed to measure DA synthesis and transport. For the investigation of postsynaptic function, several radioligands targeting dopamine one (D1) receptor and dopamine two (D2) receptor are extensively used in PET imaging studies. Moreover, we also summarized the PET imaging findings of heroin addiction studies, including heroin-induced DA increases and the reinforcement, role of DA in the long-term effects of heroin abuse, DA and vulnerability to heroin abuse and the treatment implications. PET imaging studies have corroborated the role of DA in drug addiction and increase our understanding the mechanism of drug addiction.

  9. A promising new mechanism of ionizing radiation detection for positron emission tomography: modulation of optical properties

    Science.gov (United States)

    Tao, Li; Daghighian, Henry M.; Levin, Craig S.

    2016-11-01

    Using conventional scintillation detection, the fundamental limit in positron emission tomography (PET) time resolution is strongly dependent on the inherent temporal variances generated during the scintillation process, yielding an intrinsic physical limit for the coincidence time resolution of around 100 ps. On the other hand, modulation mechanisms of the optical properties of a material exploited in the optical telecommunications industry can be orders of magnitude faster. In this paper we borrow from the concept of optics pump-probe measurement to for the first time study whether ionizing radiation can produce modulations of optical properties, which can be utilized as a novel method for radiation detection. We show that a refractive index modulation of approximately 5× {{10}-6} is induced by interactions in a cadmium telluride (CdTe) crystal from a 511 keV photon source. Furthermore, using additional radionuclide sources, we show that the amplitude of the optical modulation signal varies linearly with both the detected event rate and average photon energy of the radiation source.

  10. Positron emission tomography imaging of tumor cell metabolism and application to therapy response monitoring

    Directory of Open Access Journals (Sweden)

    Amarnath eChallapalli

    2016-02-01

    Full Text Available Cancer cells do reprogramme their energy metabolism to enable several functions such as generation of biomass including membrane biosynthesis, and overcoming bioenergetic and redox stress. In this article we review both established and evolving radioprobes developed in association with positron emission tomography (PET to detect tumor cell metabolism and effect of treatment. Measurement of enhanced tumor cell glycolysis using 2-deoxy-2-[18F]-fluoro-D-glucose is well established in the clinic. Analogues of choline including [11C]-choline and various fluorinated derivatives are being tested in several cancer types clinically with PET. In addition to these, there is an evolving array of metabolic tracers for measuring intracellular transport of glutamine and other amino acids or for measuring glycogenesis, as well as probes used as surrogates for fatty acid synthesis or precursors for fatty acid oxidation. In addition to providing us with opportunities for examining the complex regulation of reprogrammed energy metabolism in living subjects, the PET methods open up opportunities for monitoring pharmacological activity of new therapies that directly or indirectly inhibit tumor cell metabolism.

  11. Speech disorders in olivopontocerebellar atrophy correlate with positron emission tomography findings

    Energy Technology Data Exchange (ETDEWEB)

    Kluin, K.J.; Gilman, S.; Markel, D.S.; Koeppe, R.A.; Rosenthal, G.; Junck, L.

    1988-06-01

    We compared the severity of ataxic and spastic dysarthria with local cerebral metabolic rates for glucose (lCMRGlc) in 30 patients with olivopontocerebellar atrophy (OPCA). Perceptual analysis was used to examine the speech disorders, and rating scales were devised to quantitate the degree of ataxia and spasticity in the speech of each patient. lCMRGlc was measured with /sup 18/F-2-fluoro-2-deoxy-D-glucose and positron emission tomography (PET). PET studies revealed marked hypometabolism in the cerebellar hemispheres, cerebellar vermis, and brainstem of OPCA patients compared with 30 control subjects. With data normalized to the cerebral cortex, a significant inverse correlation was found between the severity of ataxia in speech and the lCMRGlc within the cerebellar vermis, cerebellar hemispheres, and brainstem, but not within the thalamus. No significant correlation was found between the severity of spasticity in speech and lCMRGlc in any of these structures. The findings support the view that the severity of ataxia in speech in OPCA is related to the functional activity of the cerebellum and its connections in the brainstem.

  12. Experience with carbon-11 choline positron emission tomography in prostate carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kotzerke, J.; Neumaier, B.; Guhlmann, A.; Reske, S.N. [Ulm Univ. (Germany). Dept. of Nuclear Medicine; Prang, J.; Volkmer, B.; Kleinschmidt, K.; Hautmann, R. [Dept. of Urology, Univ. of Ulm (Germany)

    2000-09-01

    We investigated the potential of carbon-11 choline positron emission tomography (PET) for the detection of lymph node and bone metastases in prostate cancer. A total of 23 patients were studied (known metastases: 8; suspicion of metastases: 3; primary staging: 12). Whole-body PET imaging was performed 5 min after injection of the tracer and completed within 1 h. Focally increased tracer uptake in bone or abdominal lymph node regions was interpreted as representing tumour involvement. All known bone and lymph node metastases could be recognized by [{sup 11}C]choline PET. One out of ten negative scans for primary staging was false-negative (lymph node <1 cm) and one out of two positive scans was false-positive with regard to lymph node involvement (focal bowel activity). It is concluded that [{sup 11}C]choline PET is a promising new tool for the primary staging of prostate cancer, with lymph node and bone metastases demonstrating high tracer uptake. Therapeutic management could be influenced by these results in that the technique may permit avoidance of surgical lymph node exploration. (orig.)

  13. Assessment of myocardial metabolism by positron emission tomography; Stoffwechseluntersuchungen des Herzens mit der Positronenemissionstomographie

    Energy Technology Data Exchange (ETDEWEB)

    Bengel, F.M.; Schwaiger, M. [Technische Univ. Muenchen (Germany). Nuklearmedizinische Klinik und Poliklinik

    1999-06-01

    In combination with a variety of tracers, positron emission tomography does provide noninvasive quantitative information not only about myocardial utilisation of substrates such as glucose or free fatty acids, but also about overall oxidative metabolism. PET studies of myocardial metabolism have substantially contributed to an improved understanding of regulatory mechanism as well as interaction between different substrates under normal conditions as well as under pathologic conditions such as ischemia, heart failure or diabetes mellitus, and will continue to do so in the future. (orig.) [German] Fuer die Positronenemissionstomographie stehen verschiedene Tracer zur Verfuegung, die am menschlichen Herzen nichtinvasive Quantifizierung der Utilisation von Substraten wie Glukose oder freien Fettsaeuren, aber auch des gesamten sauerstoffabhaengigen Metabolismus ermoeglichen. Stoffwechseluntersuchungen des Herzens mit der PET haben zu einem genaueren Verstaendnis von Regulationsmechanismen und Interaktionen zwischen verschiedenen Substraten sowohl im Normalzustand als auch unter pathologischen Bedingungen wie etwa bei ischaemischen Syndromen, Herzinsuffizienz oder Diabetis mellitus beigetragen. Insbesondere durch Untersuchungen von metabolischen Auswirkungen verschiedener Therapieansaetze bei Herzerkrankungen und zur Vorhersage der Effektivitaet solcher therapeutischer Strategien kann die PET auch in Zukunft einen Beitrag zur Weiterentwicklung der Kardiologie leisten. (orig.)

  14. Incidental finding of a left over guide wire on a positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Yap, Kok Hooi; Lee, Phong Teck; Buch, Mamta; Rammohan, Kandadai Seshadri

    2012-12-15

    The Seldinger technique is commonly used cannulate vessels for radiographical procedures. Loss of a guide wire into the circulation is a rare and preventable complication. It is often noticed by chance during routine radiographs. However, there is a lack of reported cases of incidental fin dings of leftover guide wire on a PET scan. An intravascular foreign body should be retrieved as soon as the diagnosis is made, to prevent complications such as embolisation or vascular damage by fractured wires. Interventional radiology is the method of choice for retrieval. We report a rare case of the coincidental finding of a lost guide wire on a PET scan. A 37 year old man presented with psychotic episodes, thigh weakness, weight gain, increased appetite and leg cramps. He was subsequently diagnosed with cushing syndrome secondary to ectopic adrenocorticotropic secretion from a right lung tumour. He subsequently underwent a staging positron emission tomography (PET) scan. The lung tumour had no uptake on PET bit had increased activity uptake on octreotide scanning. These appearances were suggestive of with carcinoid tumour. The PET scan also revealed an incidental finding of a leftover guide wire used during peripheral inserted central catheter (PICC) recently. The wire extended from right atrium to inferior vena cava. It also showed a high uptake in the adrenal glands, indicating hyperplasia, which was most likely due to adrenocorticotropic hormone stimulation. He underwent a percutaneous wire retrieval via the right femoral vein in a cardiac catheterisation laboratory and was transferred to a thoracic surgical unit for lung tumor resection.

  15. Iterative reconstruction using a Monte Carlo based system transfer matrix for dedicated breast positron emission tomography.

    Science.gov (United States)

    Saha, Krishnendu; Straus, Kenneth J; Chen, Yu; Glick, Stephen J

    2014-08-28

    To maximize sensitivity, it is desirable that ring Positron Emission Tomography (PET) systems dedicated for imaging the breast have a small bore. Unfortunately, due to parallax error this causes substantial degradation in spatial resolution for objects near the periphery of the breast. In this work, a framework for computing and incorporating an accurate system matrix into iterative reconstruction is presented in an effort to reduce spatial resolution degradation towards the periphery of the breast. The GATE Monte Carlo Simulation software was utilized to accurately model the system matrix for a breast PET system. A strategy for increasing the count statistics in the system matrix computation and for reducing the system element storage space was used by calculating only a subset of matrix elements and then estimating the rest of the elements by using the geometric symmetry of the cylindrical scanner. To implement this strategy, polar voxel basis functions were used to represent the object, resulting in a block-circulant system matrix. Simulation studies using a breast PET scanner model with ring geometry demonstrated improved contrast at 45% reduced noise level and 1.5 to 3 times resolution performance improvement when compared to MLEM reconstruction using a simple line-integral model. The GATE based system matrix reconstruction technique promises to improve resolution and noise performance and reduce image distortion at FOV periphery compared to line-integral based system matrix reconstruction.

  16. Quality assurance set-up for a new positron emission tomography detector

    Energy Technology Data Exchange (ETDEWEB)

    Cortinovis, Daniele; Xu, Chen; Zvolsky, Milan [DESY, Hamburg (Germany); Hamburg Univ. (Germany); Garutti, Erika [Hamburg Univ. (Germany); Silenzi, Alessandro [DESY, Hamburg (Germany)

    2013-07-01

    The PicoSEC-MCNet Project (PICOsecond Siliconphotomultiplier-Electronics- and Crystal research-Marie-Curie-Network) aims to develop a new class of ultra-fast photon detectors for High Energy Physics (HEP) and Positron Emission Tomography (PET). This actual technology development is covered in the EndoTOFPET-US project. A new Time Of Flight PET detector will improve the diagnosis capability of pancreatic and prostate tumors with unprecedented spatial resolution. The detector consists of two parts: a PET head mounted on an ultrasound probe and an external plate. Photons are detected by scintillating crystals individually readout by silicon photomultipliers (SiPMs). Their fast response allows to meet the critical requirement of at least 200 ps (FWHM) coincidence time resolution, essential for a spatial resolution of 3 cm along the Line Of Response (LOR) and efficient background rejection. DESY together with Hamburg University are responsible for the quality assurance and the commissioning of the whole system, and the necessary infrastructure is being set up. Within this task, the light yield uniformity for the combined scintillator-SiPM system of the external plate must be measured. This talk will introduce and describe the set-up which will allows a fast, automatic and high precision measurement of the light yield for the 4096 combined scintillator-SiPMs of the external plate.

  17. Evaluation of Glucose Uptake in Normal and Cancer Cell Lines by Positron Emission Tomography.

    Science.gov (United States)

    Maddalena, Francesca; Lettini, Giacomo; Gallicchio, Rosj; Sisinni, Lorenza; Simeon, Vittorio; Nardelli, Anna; Venetucci, Angela Assunta; Storto, Giovanni; Landriscina, Matteo

    2015-01-01

    To date, there is no definitive demonstration of the utility of positron emission tomography (PET) in studying glucose metabolism in cultured cell lines. Thus, this study was designed to compare PET to more standardized methods for the quantitative assessment of glucose uptake in nontransformed and transformed living cells and to validate PET for metabolic studies in vitro. Human colon and breast carcinoma cell lines and mouse embryo fibroblasts were evaluated for [(18)F]fluorodeoxyglucose ([(18)F]FDG) uptake by PET and autoradiography and 2-deoxyglucose (2-DG) incorporation by colorimetric assay and analyzed for the radiotoxic effects of [(18)F]FDG and the expression levels of glucose transporters. Indeed, [(18)F]FDG incorporation on PET was comparable to [(18)F]FDG uptake by autoradiography and 2-DG incorporation by colorimetric assay, although radiotracer-based methods exhibited more pronounced differences between individual cell lines. As expected, these data correlated with glucose transporters 1 to 4 and hexokinase II expression in tumor cell lines and mouse fibroblasts. Notably, [(18)F]FDG incorporation resulted in low apoptotic rates, with fibroblasts being slightly more sensitive to radiotracer-induced cell death. The quantitative analysis of [(18)F]FDG uptake in living cells by PET represents a valuable and reproducible method to study tumor cell metabolism in vitro, being representative of the differences in the molecular profile of normal and tumor cell lines.

  18. Single photon emission computed tomography in the diagnosis of Alzheimer`s disease

    Energy Technology Data Exchange (ETDEWEB)

    Hanyu, Haruo; Asano, Tetsuichi; Abe, Shin`e; Arai, Hisayuki; Iwamoto, Toshihiko; Takasaki, Masaru; Shindo, Hiroaki; Abe, Kimihiko [Tokyo Medical Coll. (Japan)

    1997-06-01

    Studies with single photon emission computed tomography (SPECT) have shown temporoparietal (TP) hypoperfusion in patients with Alzheimer`s disease (AD). We evaluated the utility of this findings in the diagnosis of AD. SPECT images with {sup 123}I-iodoamphetamine were analyzed qualitatively by a rater without knowledge of the subject`s clinical status. Sixty-seven of 302 consecutive patients were judged as having TP hypoperfusion by SPECT imaging. This perfusion pattern was observed in 44 of 51 patients with AD, in 5 with mixed dementia, 8 with cerebrovascular disease (including 5 with dementia), 4 with Parkinson`s disease (including 2 with dementia), 1 with normal pressure hydrocephalus, 1 with slowly progressive aphasia, 1 with progressive autonomic failure, 2 with age-associated memory impairment, and 1 with unclassified dementia. The sensitivity for AD was 86.3% (44 of 51 AD), and the specificity was 91.2% (229 of 251 non-AD). Next, we looked for differences in perfusion images between patients with AD and without AD. Some patients without AD had additional hypoperfusion beyond TP areas: deep gray matter hypoperfusion and diffuse frontal hypoperfusion, which could be used to differentiate them from the patients with AD. Others could not be distinguished from patients with AD by their perfusion pattern. Although patients with other cerebral disorders occasionally have TP hypoperfusion, this finding makes the diagnosis of AD very likely. (author)

  19. Bone single photon emission computed tomography (SPECT in a patient with Pancoast tumor: a case report

    Directory of Open Access Journals (Sweden)

    Hamid Javadi

    Full Text Available CONTEXT: Non-small cell lung carcinomas (NSCLCs of the superior sulcus are considered to be the most challenging type of malignant thoracic disease. In this disease, neoplasms originating mostly from the extreme apex of the lung expand to the chest wall and thoracic inlet structures. Multiple imaging procedures have been applied to identify tumors and to stage and predict tumor resectability in surgical operations. Clinical examinations to localize pain complaints in shoulders and down the arms, and to screen for Horner's syndrome and abnormalities seen in paraclinical assessments, have been applied extensively for differential diagnosis of superior sulcus tumors. Although several types of imaging have been utilized for diagnosing and staging Pancoast tumors, there have been almost no reports on the efficiency of whole-body bone scans (WBBS for detecting the level of abnormality in cases of superior sulcus tumors. CASE REPORT: We describe a case of Pancoast tumor in which technetium-99m methylene diphosphonate (Tc-99m MDP bone single-photon emission-computed tomography (SPECT was able to accurately detect multiple areas of abnormality in the vertebrae and ribs. In describing this case, we stress the clinical and diagnostic points, in the hope of stimulating a higher degree of suspicion and thereby facilitating appropriate diagnosis and treatment. From the results of this study, further clinical trials to evaluate the potential of SPECT as an efficient imaging tool for the work-up on cases of Pancoast tumor are recommended.

  20. Utility of positron emission tomography-magnetic resonance imaging in musculoskeletal imaging

    Institute of Scientific and Technical Information of China (English)

    Ammar A Chaudhry; Maryam Gul; Elaine Gould; Mathew Teng; Kevin Baker; Robert Matthews

    2016-01-01

    Differentiation between neoplastic and nonneoplastic conditions magnetic resonance imaging(MRI) has established itself as one of the key clinical tools in evaluation of musculoskeletal pathology. However, MRI still has several key limitations which require supplemental information from additional modalities to complete evaluation of various disorders. This has led to the development hybrid positron emission tomography(PET)-MRI which is rapidly evolving to address key clinical questions by using the morphological strengths of MRI and functional information of PET imaging. In this article, we aim to review physical principles and techniques of PET-MRI and discuss clinical utility of functional information obtained from PET imaging and structural information obtained from MRI imaging for the evaluation of musculoskeletal pathology. More specifically, this review highlights the role of PET-MRI in musculoskeletal oncology including initial diagnosis and staging, treatment planning and posttreatment follow-up. Also we will review utility of PET-MRI in evaluating musculoskeletal infections(especially in the immunocompromised and diabetics) and inflammatory condition. Additionally, common pitfalls of PET-MRI will be addressed.

  1. FPGA-Based Front-End Electronics for Positron Emission Tomography.

    Science.gov (United States)

    Haselman, Michael; Dewitt, Don; McDougald, Wendy; Lewellen, Thomas K; Miyaoka, Robert; Hauck, Scott

    2009-02-22

    Modern Field Programmable Gate Arrays (FPGAs) are capable of performing complex discrete signal processing algorithms with clock rates above 100MHz. This combined with FPGA's low expense, ease of use, and selected dedicated hardware make them an ideal technology for a data acquisition system for positron emission tomography (PET) scanners. Our laboratory is producing a high-resolution, small-animal PET scanner that utilizes FPGAs as the core of the front-end electronics. For this next generation scanner, functions that are typically performed in dedicated circuits, or offline, are being migrated to the FPGA. This will not only simplify the electronics, but the features of modern FPGAs can be utilizes to add significant signal processing power to produce higher resolution images. In this paper two such processes, sub-clock rate pulse timing and event localization, will be discussed in detail. We show that timing performed in the FPGA can achieve a resolution that is suitable for small-animal scanners, and will outperform the analog version given a low enough sampling period for the ADC. We will also show that the position of events in the scanner can be determined in real time using a statistical positioning based algorithm.

  2. Eyeblink conditioning in unmedicated schizophrenia patients: a positron emission tomography study.

    Science.gov (United States)

    Parker, Krystal L; Andreasen, Nancy C; Liu, Dawei; Freeman, John H; O'Leary, Daniel S

    2013-12-30

    Previous studies suggest that patients with schizophrenia exhibit dysfunctions in a widely distributed circuit-the cortico-cerebellar-thalamic-cortical circuit, or CCTCC-and that this may explain the multiple cognitive deficits observed in the disorder. This study uses positron emission tomography (PET) with O(15) H₂O to measure regional cerebral blood flow (rCBF) in response to a classic test of cerebellar function, the associative learning that occurs during eyeblink conditioning, in a sample of 20 unmedicated schizophrenia patients and 20 closely matched healthy controls. The PET paradigm examined three phases of acquisition and extinction (early, middle and late). The patients displayed impaired behavioral performance during both acquisition and extinction. The imaging data indicate that, compared to the control subjects, the patients displayed decreases in rCBF in all three components of the CCTCC during both acquisition and extinction. Specifically, patients had less rCBF in the middle and medial frontal lobes, anterior cerebellar lobules I/V and VI, as well as the thalamus during acquisition and although similar areas were found in the frontal lobe, ipsilateral cerebellar lobule IX showed consistently less activity in patients during extinction. Thus this study provides additional support for the hypothesis that patients with schizophrenia have a cognitive dysmetria--an inability to smoothly coordinate many different types of mental activity--that affects even a very basic cognitive task that taps into associative learning.

  3. Aspects of positron emission tomography radiochemistry as relevant for food chemistry.

    Science.gov (United States)

    Wuest, F

    2005-12-01

    Positron emission tomography (PET) is a medical imaging technique using compounds labelled with short-lived positron emitting radioisotopes to obtain functional information of physiological, biochemical and pharmacological processes in vivo. The need to understand the potential link between the ingestion of individual dietary agents and the effect of health promotion or health risk requires the exact metabolic characterization of food ingredients in vivo. This exciting but rather new research field of PET would provide new insights and perspectives on food chemistry by assessing quantitative information on pharmocokinetics and pharmacodynamics of food ingredients and dietary agents. To fully exploit PET technology in food chemistry appropriately radiolabelled compounds as relevant for food sciences are needed. The most widely used short-lived positron emitters are (11)C (t(1/2) = 20.4 min) and (18)F (t(1/2) = 109.8 min). Longer-lived radioisotopes are available by using (76)Br (t(1/2) = 16.2 h) and (124)I (t(1/2) = 4.12 d). The present review article tries to discuss some aspects for the radiolabelling of food ingredients and dietary agents either by means of isotopic labelling with (11)C or via prosthetic group labelling approaches using the positron emitting halogens (18)F, (76)Br and (124)I.

  4. A fast rebinning algorithm for 3D positron emission tomography using John's equation

    Science.gov (United States)

    Defrise, Michel; Liu, Xuan

    1999-08-01

    Volume imaging in positron emission tomography (PET) requires the inversion of the three-dimensional (3D) x-ray transform. The usual solution to this problem is based on 3D filtered-backprojection (FBP), but is slow. Alternative methods have been proposed which factor the 3D data into independent 2D data sets corresponding to the 2D Radon transforms of a stack of parallel slices. Each slice is then reconstructed using 2D FBP. These so-called rebinning methods are numerically efficient but are approximate. In this paper a new exact rebinning method is derived by exploiting the fact that the 3D x-ray transform of a function is the solution to the second-order partial differential equation first studied by John. The method is proposed for two sampling schemes, one corresponding to a pair of infinite plane detectors and another one corresponding to a cylindrical multi-ring PET scanner. The new FORE-J algorithm has been implemented for this latter geometry and was compared with the approximate Fourier rebinning algorithm FORE and with another exact rebinning algorithm, FOREX. Results with simulated data demonstrate a significant improvement in accuracy compared to FORE, while the reconstruction time is doubled. Compared to FOREX, the FORE-J algorithm is slightly less accurate but more than three times faster.

  5. Function of the shoulder muscles during arm elevation: an assessment using positron emission tomography

    Science.gov (United States)

    Omi, Rei; Sano, Hirotaka; Ohnuma, Masahiro; Kishimoto, Koshi N; Watanuki, Shoichi; Tashiro, Manabu; Itoi, Eiji

    2010-01-01

    Although 2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography (PET) has been used for the assessment of skeletal muscle activities, its application to the shoulder muscles is only sparse. The purpose of this study was to investigate the activities of the shoulder muscles during arm elevation using PET. Six healthy volunteers performed an arm elevation exercise before and after FDG injection. The exercise consisted of 200 repetitions of arm elevation in the scapular plane with a 0.25-kg weight fixed to the wrist on both arms. PET examination was performed 50 min after FDG injection. For control data, PET scan was repeated for each subject on a separate day without any exercise. The volume of interest was established for each shoulder muscle. The subscapularis was divided into three portions (superior, middle, and inferior). The standardized uptake value (SUV) was calculated in each muscle to quantify its activity. The SUVs increased significantly after exercise in the deltoid, supraspinatus, and the superior portion of subscapularis. Among three divided portions of the subscapularis, the SUV of the superior one-third was significantly greater than the rest of the muscle after exercise. Our current study clearly indicated that there were two functionally different portions in the subscapularis muscle and the superior one-third played an important role during arm elevation in the scapular plane. PMID:20298439

  6. Pretargeted Positron Emission Tomography Imaging That Employs Supramolecular Nanoparticles with in Vivo Bioorthogonal Chemistry.

    Science.gov (United States)

    Hou, Shuang; Choi, Jin-Sil; Garcia, Mitch Andre; Xing, Yan; Chen, Kuan-Ju; Chen, Yi-Ming; Jiang, Ziyue K; Ro, Tracy; Wu, Lily; Stout, David B; Tomlinson, James S; Wang, Hao; Chen, Kai; Tseng, Hsian-Rong; Lin, Wei-Yu

    2016-01-26

    A pretargeted oncologic positron emission tomography (PET) imaging that leverages the power of supramolecular nanoparticles with in vivo bioorthogonal chemistry was demonstrated for the clinically relevant problem of tumor imaging. The advantages of this approach are that (i) the pharmacokinetics (PKs) of tumor-targeting and imaging agents can be independently altered via chemical alteration to achieve the desired in vivo performance and (ii) the interplay between the two PKs and other controllable variables confers a second layer of control toward improved PET imaging. In brief, we utilized supramolecular chemistry to synthesize tumor-targeting nanoparticles containing transcyclooctene (TCO, a bioorthogonal reactive motif), called TCO⊂SNPs. After the intravenous injection and subsequent concentration of the TCO⊂SNPs in the tumors of living mice, a small molecule containing both the complementary bioorthogonal motif (tetrazine, Tz) and a positron-emitting radioisotope ((64)Cu) was injected to react selectively and irreversibly to TCO. High-contrast PET imaging of the tumor mass was accomplished after the rapid clearance of the unreacted (64)Cu-Tz probe. Our nanoparticle approach encompasses a wider gamut of tumor types due to the use of EPR effects, which is a universal phenomenon for most solid tumors.

  7. Assessment of diabetic neuropathy with emission tomography and magnetic resonance spectroscopy.

    Science.gov (United States)

    Rao, Harshvardhan; Gaur, Neeraj; Tipre, Dnyanesh

    2017-04-01

    Diabetic neuropathies (DNs) are nerve-damaging disorders associated with diabetes. They are commonly attributed to peripheral nerves and primarily affect the limbs of the patient. They cause altered sensitivity to external stimuli along with loss in balance and reflexes of the affected patient. DNs are associated with a variety of clinical manifestations including autonomic failure and are caused by poor management of blood sugar levels. Imaging modalities provide vital information about early physiological changes in DNs. This review summarizes contributions by various teams of scientists in developing imaging methods to assess physiological changes in DNs and ongoing clinical trials where imaging modalities are applied to evaluate therapeutic intervention in DNs. Development of PET, single photon emission computed tomography, and magnetic resonance spectroscopy methods over the past 20 years are reviewed in the diagnostic assessment of DNs. Abnormal radiotracer pharmacokinetics and neurometabolite spectra in affected organs confirm physiological abnormalities in DN. With the use of the Siemens Biograph mMR and GE Signa - 60 cm (PET/MRI scanner), simultaneous acquisition of physiological and anatomical information could enhance understanding of DNs and accelerate drug development.

  8. Impact of Single-Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) and Positron Emission Tomography/Computed Tomography (PET/CT) in the Diagnosis of Traumatic Brain Injury (TBI): Case Report.

    Science.gov (United States)

    Molina-Vicenty, Irma L; Santiago-Sánchez, Michelaldemar; Vélez-Miró, Iván; Motta-Valencia, Keryl

    2016-09-01

    Traumatic brain injury (TBI) is defined as damage to the brain resulting from an external force. TBI, a global leading cause of death and disability, is associated with serious social, economic, and health problems. In cases of mild-to-moderate brain damage, conventional anatomical imaging modalities may or may not detect the cascade of metabolic changes that have occurred or are occurring at the intracellular level. Functional nuclear medicine imaging and neurophysiological parameters can be used to characterize brain damage, as the former provides direct visualization of brain function, even in the absence of overt behavioral manifestations or anatomical findings. We report the case of a 30-year-old Hispanic male veteran who, after 2 traumatic brain injury events, developed cognitive and neuropsychological problems with no clear etiology in the presence of negative computed tomography (CT) findings.

  9. Significance of incidental focal uptake in prostate on 18-fluoro-2-deoxyglucose positron emission tomography CT images

    OpenAIRE

    Han, E J; H O, J; Choi, W H; Yoo, I R; Chung, S K

    2010-01-01

    To evaluate the clinical significance of incidental focal prostate fluorodeoxyglucose (FDG) uptake, we reviewed 18-F-FDG positron emission tomography (PET)/CT scans from 2003 to 2007 and selected cases with focal FDG uptake in prostate. Cases of known prostate cancer were excluded. The maximum standardised uptake value (SUVmax), site (central or peripheral) and pattern (discrete or ill-defined) of FDG uptake, calcification (present or absent) and prostate volume (

  10. Kinetic Analysis of Dynamic Positron Emission Tomography Data using Open-Source Image Processing and Statistical Inference Tools

    OpenAIRE

    Hawe, David; Hernández Fernández, Francisco R.; O’Suilleabháin, Liam; Huang, Jian; Wolsztynski, Eric; O’Sullivan, Finbarr

    2012-01-01

    In dynamic mode, positron emission tomography (PET) can be used to track the evolution of injected radio-labelled molecules in living tissue. This is a powerful diagnostic imaging technique that provides a unique opportunity to probe the status of healthy and pathological tissue by examining how it processes substrates. The spatial aspect of PET is well established in the computational statistics literature. This article focuses on its temporal aspect. The interpretation of PET time-course da...

  11. Characteristics of glucose metabolism and amyloid deposition by positron emission tomography images in Alzheimer’s disease

    Institute of Scientific and Technical Information of China (English)

    纪勇

    2013-01-01

    Objective To investigate positron emission tomography (PET) image characteristics of glucose metabolism and amyloid deposition as demonstrated by fluorodeoxyglucose (18F-FDG) and Pittsburgh Compound B (PiB) in Alzheimer’s disease (AD) .Methods Patients with mild AD and moderate AD (n=6,each) were included in this study.6 healthy subjects were selected as normal controls.Cognitive function was assessed by the minimental state examination,Montreal Cognitive Assessment and Clinical Dementia Rating.Ventricular dilation,cor-

  12. Particle physics methodologies applied to time-of-flight positron emission tomography with silicon-photomultipliers and inorganic scintillators

    OpenAIRE

    Leming, Edward J

    2015-01-01

    Positron emission tomography, or PET, is a medical imaging technique which has been used in clinical environments for over two decades. With the advent of fast timing detectors and scintillating crystals, it is possible to envisage improvements to the technique\\ud with the inclusion of time-of-flight capabilities. In this context, silicon photomultipliers coupled to fast inorganic LYSO crystals are investigated as a possible technology choice. As part of the ENVISION collaboration a range of ...

  13. Heterogeneity of Monosymptomatic Resting Tremor in a Prospective Study: Clinical Features, Electrophysiological Test, and Dopamine Transporter Positron Emission Tomography

    OpenAIRE

    Hua-Guang Zheng; Rong Zhang; Xin Li; Fang-Fei Li; Ya-Chen Wang; Xue-Mei Wang; Ling-Long Lu; Tao Feng

    2015-01-01

    Background: The relationship between monosymptomatic resting tremor (mRT) and Parkinson′s disease (PD) remains controversial. In this study, we aimed to assess the function of presynaptic dopaminergic neurons in patients with mRT by dopamine transporter positron emission tomography (DAT-PET) and to evaluate the utility of clinical features or electrophysiological studies in differential diagnosis. Methods: Thirty-three consecutive patients with mRT were enrolled prospectively. The Unified...

  14. Lymphocytic Thyroiditis Presenting as a Focal Uptake on 18F-Fluorodeoxyglucose Positron Emission Tomography: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Tae Seok; Kim, Eun Kyung; Lee, Sarah; Moon, Hee Jung; Kwak, Jin Young [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2011-12-15

    Diffuse increased uptake on 18F-Fluorodeoxyglucose Positron Emission Tomography (18F FDG PET) is a well-known finding of the lymphocytic thyroiditis. Nevertheless, a pathologic confirmation is needed in cases of a focal 18F FDG uptake in the thyroid gland. This article reports a rare case of a focal 18F FDG uptake lesion by PET, which was revealed pathologically to be lymphocytic thyroiditis

  15. [Analysis of single-photon emission computed tomography in patients with hypertensive encephalopathy complicated with previous hypertensive crisis].

    Science.gov (United States)

    Kustkova, H S

    2012-01-01

    In cerebrovascular diseases pefuzionnaya single photon emission computed tomography with lipophilic amines used for the diagnosis of functional disorders of cerebral blood flow. Quantitative calculations helps clarify the nature of vascular disease and clarify the adequacy and effectiveness of the treatment. In this modern program for SPECT ensure conduct not only as to the calculation of blood flow, but also make it possible to compute also the absolute values of cerebral blood flow.

  16. Comparison of five segmentation tools for 18F-fluoro-deoxy-glucose-positron emission tomography-based target volume definition in head and neck cancer.

    NARCIS (Netherlands)

    Schinagl, D.A.X.; Vogel, W.V.; Hoffmann, A.L.; Dalen, J.A. van; Oyen, W.J.G.; Kaanders, J.H.A.M.

    2007-01-01

    PURPOSE: Target-volume delineation for radiation treatment to the head and neck area traditionally is based on physical examination, computed tomography (CT), and magnetic resonance imaging. Additional molecular imaging with (18)F-fluoro-deoxy-glucose (FDG)-positron emission tomography (PET) may imp

  17. Neurofibroma of the breast detected on position emission tomography-CT in a patient with neurofibromatosis type 1: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ho Seok; Kim, Hye Jung; Yang, Bang; Lee So Mi; Jeong, Ji Yun [Kyungpook National University Hospital, Daegu(Korea, Republic of)

    2016-02-15

    Neurofibromas of the breast are rare. They are commonly found as solitary lesions or parts of neurofibromatosis type 1 and are usually located on the nipple-areolar area. We describe a case of neurofibroma of the breast in the retromammary space, which was detected on positron emission tomography-computed tomography after hysterectomy due to endometrial cancer.

  18. Quantification of myocardial perfusion using cardiac magnetic resonance imaging correlates significantly to rubidium-82 positron emission tomography in patients with severe coronary artery disease

    DEFF Research Database (Denmark)

    Qayyum, Abbas A; Hasbak, Philip; Larsson, Henrik B W

    2014-01-01

    INTRODUCTION: Aim was to compare absolute myocardial perfusion using cardiac magnetic resonance imaging (CMRI) based on Tikhonov's procedure of deconvolution and rubidium-82 positron emission tomography (Rb-82 PET). MATERIALS AND METHODS: Fourteen patients with coronary artery stenosis underwent ...

  19. Traditional versus up-front [F-18] fluorodeoxyglucose-positron emission tomography staging of non-small-cell lung cancer : A Dutch cooperative randomized study

    NARCIS (Netherlands)

    Herder, GJM; Kramer, H; Hoekstra, OS; Smit, EF; Pruim, J; van Tinteren, H; Comans, EF; Verboom, P; Uyl-De Groot, CA; Welling, A; Paul, MA; Boers, M; Postmus, PE; Teule, GJ; Groen, HJM

    2006-01-01

    Purpose We investigated whether application of positron emission tomography (PET) immediately after first presentation might simplify staging while maintaining accuracy, as compared with traditional strategy in routine clinical setting. Methods At first presentation, patients with a provisional diag

  20. Spatiotemporal Stability of Cu-ATSM and FLT Positron Emission Tomography Distributions During Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Bradshaw, Tyler J.; Yip, Stephen; Jallow, Ngoneh [Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin (United States); Forrest, Lisa J. [Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, Wisconsin (United States); Jeraj, Robert, E-mail: rjeraj@wisc.edu [Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin (United States); Department of Human Oncology, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin (United States)

    2014-06-01

    Purpose: In dose painting, in which functional imaging is used to define biological targets for radiation therapy dose escalation, changes in spatial distributions of biological properties during treatment can compromise the quality of therapy. The goal of this study was to assess the spatiotemporal stability of 2 potential dose painting targets—hypoxia and proliferation—in canine tumors during radiation therapy. Methods and Materials: Twenty-two canine patients with sinonasal tumors (14 carcinoma and 8 sarcoma) were imaged before hypofractionated radiation therapy with copper(II)-diacetyl-bis(N4-methylthiosemicarbazone) (Cu-ATSM) positron emission tomography/computed tomography (PET/CT) for hypoxia and 3′-deoxy-3′-{sup 18}F-fluorothymidine (FLT) PET/CT for proliferation. The FLT scans were repeated after 2 fractions and the Cu-ATSM scans after 3 fractions. Midtreatment PET/CT images were deformably registered to pretreatment PET/CT images. Voxel-based Spearman correlation coefficients quantified the spatial stability of Cu-ATSM and FLT uptake distributions between pretreatment and midtreatment scans. Paired t tests determined significant differences between the patients' respective Cu-ATSM and FLT correlations coefficients. Standardized uptake value measures were also compared between pretreatment and midtreatment scans by use of paired t tests. Results: Spatial distributions of Cu-ATSM and FLT uptake were stable through midtreatment for both sarcomas and carcinomas: the population mean ± standard deviation in Spearman correlation coefficient was 0.88 ± 0.07 for Cu-ATSM and 0.79 ± 0.13 for FLT. The patients' Cu-ATSM correlation coefficients were significantly higher than their respective FLT correlation coefficients (P=.001). Changes in Cu-ATSM SUV measures from pretreatment to midtreatment were histology dependent: carcinomas experienced significant decreases in Cu-ATSM uptake (P<.05), whereas sarcomas did not (P>.20). Both histologies

  1. A Gaussian mixture model for definition of lung tumor volumes in positron emission tomography.

    Science.gov (United States)

    Aristophanous, Michalis; Penney, Bill C; Martel, Mary K; Pelizzari, Charles A

    2007-11-01

    The increased interest in 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in radiation treatment planning in the past five years necessitated the independent and accurate segmentation of gross tumor volume (GTV) from FDG-PET scans. In some studies the radiation oncologist contours the GTV based on a computed tomography scan, while incorporating pertinent data from the PET images. Alternatively, a simple threshold, typically 40% of the maximum intensity, has been employed to differentiate tumor from normal tissue, while other researchers have developed algorithms to aid the PET based GTV definition. None of these methods, however, results in reliable PET tumor segmentation that can be used for more sophisticated treatment plans. For this reason, we developed a Gaussian mixture model (GMM) based segmentation technique on selected PET tumor regions from non-small cell lung cancer patients. The purpose of this study was to investigate the feasibility of using a GMM-based tumor volume definition in a robust, reliable and reproducible way. A GMM relies on the idea that any distribution, in our case a distribution of image intensities, can be expressed as a mixture of Gaussian densities representing different classes. According to our implementation, each class belongs to one of three regions in the image; the background (B), the uncertain (U) and the target (T), and from these regions we can obtain the tumor volume. User interaction in the implementation is required, but is limited to the initialization of the model parameters and the selection of an "analysis region" to which the modeling is restricted. The segmentation was developed on three and tested on another four clinical cases to ensure robustness against differences observed in the clinic. It also compared favorably with thresholding at 40% of the maximum intensity and a threshold determination function based on tumor to background image intensities proposed in a recent paper. The parts of the

  2. 18F-fluorodeoxyglucose positron emission tomography in the diagnosis of small pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Keiichi Okano; Keitaro Kakinoki; Shintaro Akamoto; Masanobu Hagiike; Hisashi Usuki; Yuka Yamamoto; Yoshihiro Nishiyama; Yasuyuki Suzuki

    2011-01-01

    AIM: To investigate the role of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) in the diagnosis of small pancreatic cancer.METHODS: This study involved 31 patients with proven invasive ductal cancer of the pancreas. The patients were divided into 3 groups according to the maximum diameter of the tumor: TS1 (maximum tumor size ≤ 2.0 cm),TS2 (> 2.0 cm and ≤ 4.0 cm) or TS3-4 (> 4.0 cm). The relationships between the TS and various diagnostic tools, including FDG-PET with dual time point evaluation,were analyzed.RESULTS: The tumors ranged from 1.3 to 11.0 cm in diameter. Thirty of the 31 patients (97%) had a positive FDG-PET study. There were 5 patients classified as TS1,15 as TS2 and 11 as TS3-4. The sensitivity of FDG-PET,computed tomography (CT) and magnetic resonance imaging (MRI) were 100%, 40%, 0% in TS1, 93%,93%, 89% in TS2 and 100%, 100%, 100% in TS3-4.The sensitivity of FDG-PET was significantly higher in comparison to CT and MRI in patients with TS1 (P <0.032). The mean standardized uptake values (SUVs)did not show a significant difference in relation to the TS (TS1: 5.8 ± 4.5, TS2: 5.7 ± 2.2, TS3-4: 8.2 ± 3.9),respectively. All the TS1 tumors (from 13 to 20 mm)showed higher SUVs in FDG-PET with dual time point evaluation in the delayed phase compared with the early phase, which suggested the lesions were malignant.CONCLUSION: These results indicate that FDG-PET with dual time point evaluation is a useful modality for the detection of small pancreatic cancers with a diameter of less than 20 mm.

  3. 18F-AV-1451 positron emission tomography in Alzheimer’s disease and progressive supranuclear palsy

    Science.gov (United States)

    Vázquez Rodríguez, Patricia; Hong, Young T.; Allinson, Kieren S. J.; Williamson, David; Borchert, Robin J.; Sami, Saber; Cope, Thomas E.; Bevan-Jones, W. Richard; Jones, P. Simon; Arnold, Robert; Surendranathan, Ajenthan; Mak, Elijah; Su, Li; Fryer, Tim D.; Aigbirhio, Franklin I.; O’Brien, John T.; Rowe, James B.

    2017-01-01

    Abstract The ability to assess the distribution and extent of tau pathology in Alzheimer’s disease and progressive supranuclear palsy in vivo would help to develop biomarkers for these tauopathies and clinical trials of disease-modifying therapies. New radioligands for positron emission tomography have generated considerable interest, and controversy, in their potential as tau biomarkers. We assessed the radiotracer 18F-AV-1451 with positron emission tomography imaging to compare the distribution and intensity of tau pathology in 15 patients with Alzheimer’s pathology (including amyloid-positive mild cognitive impairment), 19 patients with progressive supranuclear palsy, and 13 age- and sex-matched controls. Regional analysis of variance and a support vector machine were used to compare and discriminate the clinical groups, respectively. We also examined the 18F-AV-1451 autoradiographic binding in post-mortem tissue from patients with Alzheimer’s disease, progressive supranuclear palsy, and a control case to assess the 18F-AV-1451 binding specificity to Alzheimer’s and non-Alzheimer’s tau pathology. There was increased 18F-AV-1451 binding in multiple regions in living patients with Alzheimer’s disease and progressive supranuclear palsy relative to controls [main effect of group, F(2,41) = 17.5, P 2.2, P’s 2.7, P’s < 0.02). The support vector machine assigned patients’ diagnoses with 94% accuracy. The post-mortem autoradiographic data showed that 18F-AV-1451 strongly bound to Alzheimer-related tau pathology, but less specifically in progressive supranuclear palsy. 18F-AV-1451 binding to the basal ganglia was strong in all groups in vivo. Postmortem histochemical staining showed absence of neuromelanin-containing cells in the basal ganglia, indicating that off-target binding to neuromelanin is an insufficient explanation of 18F-AV-1451 positron emission tomography data in vivo, at least in the basal ganglia. Overall, we confirm the potential of 18F

  4. Dynamic Imaging of Fluid Flow in Sandstones by Nuclear Emission Tomography

    Science.gov (United States)

    Pini, Ronny; Benson, Sally; Druhan, Jenny; Hingerl, Ferdinand; O'Neil, James P.; Vandehey, Nicholas T.

    2014-05-01

    The heterogeneity of geological formations varies over a wide range of length-scales and represents a major challenge for predicting the movement of fluids in the subsurface. Millimeters to cm-scale features that are commonly observed in sedimentary rocks have been shown to greatly influence fluid transport over much larger observational scales. From a practical perspective, these features give rise to capillary phenomena that affect process-relevant parameters, such as sweep or trapping efficiencies. Measurements on core samples represent a major input for field-scale flow models and the latter adopt multistage up-scaling approaches to link the core-scale to the size of a grid-block. The lack of access to information about rock property heterogeneity at the sub-core scale has restricted the ability to fully take advantage of these methods; in fact, properties derived from the latter are inherently "effective", their spatial resolution being limited to a minimum of several centimeters by the measurement or sampling technique. However, making accurate predictions of multiphase flows and dispersion coefficients for single phase flow requires making measurements at the full range of relevant spatial scales, thus referring to the internal structure of the sample and the small-scale features described above. Essential components in this description include continuum properties that are related to the rock (porosity and permeability), to the fluids (saturation) and to both of them (capillary pressure-saturation relationship); the ability to create a link among all these properties is key to a physically-sound description of these naturally complex systems. One way to accomplish this is by adopting an integrated approach that combines displacement experiments in naturally heterogeneous core-samples with the simultaneous imaging of flow as well as with the support of detailed numerical simulations. In this paper, nuclear emission tomography is applied to visualize fluid

  5. Positron emission tomography (PET) study of patients with pituitary adenoma using labeled amino acid

    Energy Technology Data Exchange (ETDEWEB)

    Mineura, Katsuyoshi; Sasajima, Toshio; Sakamoto, Tetsuya; Kowada, Masayoshi (Akita Univ. (Japan). Hospital); Shishido, Fumio; Uemura, Kazuo

    1989-12-01

    Four cases with pituitary adenomas were studied using {sup 11}C-L-methionine (C-11 Met) positron-emission tomography (PET). The C-11 Met was intravenously administered at a dose of 0.6 mCi/kg. The uptake of the tracer for tumors was calculated on the PET images 45 min after the injection; the uptake index was represented as a percentage of the total count in the arterial blood over a period of 45 min. In all cases, the C-11 Met accumulated intensely in the tumor regions; the PET images clearly delineated the extent of the tumor. The C-11 Met uptake index for pituitary adenomas varied widely from 3.94 x 10{sup -2}% to 15.36 x 10{sup -2}%, with a mean of 7.87 x 10{sup -2}%. These indices for the tumors increased markedly in comparison with that of the contralateral left temporal gray matter as a nontumor region (1.89 x 10{sup -2}% to 2.43 x 10{sup -2}% with a mean of 2.06 x 10{sup -2}%). In a case of prolactinoma, repeated PET following bromocriptine treatment showed a decrease in the C-11 Met uptake index; this decrease reflected changes in the serum prolactin value. In another case with ACTH-producing adenoma, the T/NT (tumor/nontumor) ratio fell from 3.44 to 2.40; however, the C-11 Met index remained unchanged. C-11 Met PET images facilitate determining the extent of pituitary adenomas and the monitoring of tumor response to treatment. Further application may give useful knowledge on the amino-acid metabolism of the tumor. (author).

  6. Importance of defect detectability in Positron Emission Tomography imaging of abdominal lesions

    Directory of Open Access Journals (Sweden)

    Shozo Yamashita

    2015-07-01

    Full Text Available Objective(s: This study was designed to assess defect detectability in positron emission tomography (PET imaging of abdominal lesions. Methods: A National Electrical Manufactures Association International Electrotechnical Commission phantom was used. The simulated abdominal lesion was scanned for 10 min using dynamic list-mode acquisition method. Images, acquired with scan duration of 1-10 min, were reconstructed using VUE point HD and a 4.7 mm full-width at half-maximum (FWHM Gaussian filter. Iteration-subset combinations of 2-16 and 2-32 were used. Visual and physical analyses were performed using the acquired images. To sequentially evaluate defect detectability in clinical settings, we examined two middle-aged male subjects. One had a liver cyst (approximately 10 mm in diameter and the other suffered from pancreatic cancer with an inner defect region (approximately 9 mm in diameter. Results: In the phantom study, at least 6 and 3 min acquisition durations were required to visualize 10 and 13 mm defect spheres, respectively. On the other hand, spheres with diameters ≥17 mm could be detected even if the acquisition duration was only 1 min. The visual scores were significantly correlated with background (BG variability. In clinical settings, the liver cyst could be slightly visualized with an acquisition duration of 6 min, although image quality was suboptimal. For pancreatic cancer, the acquisition duration of 3 min was insufficient to clearly describe the defect region. Conclusion: The improvement of BG variability is the most important factor for enhancing lesion detection. Our clinical scan duration (3 min/bed may not be suitable for the detection of small lesions or accurate tumor delineation since an acquisition duration of at least 6 min is required to visualize 10 mm lesions, regardless of reconstruction parameters. Improvements in defect detectability are important for radiation treatment planning and accurate PET-based diagnosis.

  7. Importance of Defect Detectability in Positron Emission Tomography Imaging of Abdominal Lesions

    Science.gov (United States)

    Yamashita, Shozo; Yokoyama, Kunihiko; Onoguchi, Masahisa; Yamamoto, Haruki; Nakaichi, Tetsu; Tsuji, Shiro; Nakajima, Kenichi

    2015-01-01

    Objective(s): This study was designed to assess defect detectability in positron emission tomography (PET) imaging of abdominal lesions. Methods: A National Electrical Manufactures Association International Electrotechnical Commission phantom was used. The simulated abdominal lesion was scanned for 10 min using dynamic list-mode acquisition method. Images, acquired with scan duration of 1-10 min, were reconstructed using VUE point HD and a 4.7 mm full-width at half-maximum (FWHM) Gaussian filter. Iteration-subset combinations of 2-16 and 2-32 were used. Visual and physical analyses were performed using the acquired images. To sequentially evaluate defect detectability in clinical settings, we examined two middle-aged male subjects. One had a liver cyst (approximately 10 mm in diameter) and the other suffered from pancreatic cancer with an inner defect region (approximately 9 mm in diameter). Results: In the phantom study, at least 6 and 3 min acquisition durations were required to visualize 10 and 13 mm defect spheres, respectively. On the other hand, spheres with diameters ≥17 mm could be detected even if the acquisition duration was only 1 min. The visual scores were significantly correlated with background (BG) variability. In clinical settings, the liver cyst could be slightly visualized with an acquisition duration of 6 min, although image quality was suboptimal. For pancreatic cancer, the acquisition duration of 3 min was insufficient to clearly describe the defect region. Conclusion: The improvement of BG variability is the most important factor for enhancing lesion detection. Our clinical scan duration (3 min/bed) may not be suitable for the detection of small lesions or accurate tumor delineation since an acquisition duration of at least 6 min is required to visualize 10 mm lesions, regardless of reconstruction parameters. Improvements in defect detectability are important for radiation treatment planning and accurate PET-based diagnosis. PMID:27408887

  8. {sup 18}F-FDG positron emission tomography in the early diagnosis of enterocolitis: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Kresnik, E.; Gallowitsch, H.J.; Igerc, I.; Kumnig, G.; Gomez, I.; Lind, P. [Nuclear Medicine and Special Endocrinology, PET Centre, General Hospital, St. Veiterstrasse 47, 9020 Klagenfurt (Austria); Mikosch, P.; Alberer, D.; Hebenstreit, A. [Department of Internal Medicine and Gastroenterology, General Hospital, Klagenfurt (Austria); Wuertz, F. [Department of Pathology, General Hospital, Klagenfurt (Austria); Kogler, D.; Gasser, J. [Department of Radiology, General Hospital, Klagenfurt (Austria)

    2002-10-01

    Collagenous and eosinophilic colitis are rare diseases characterised by chronic watery diarrhoea. Radiographic evaluation of the gastrointestinal tract and colonoscopy are usually non-diagnostic since as many as one-third of patients will have minor abnormalities. To date a few investigators have reported increased fluorine-18 fluorodeoxyglucose ({sup 18}F-FDG) uptake on positron emission tomography (PET) in patients with acute enterocolitis, but there have been no reports on the use of {sup 18}F-FDG PET for the diagnosis of collagenous or eosinophilic colitis in an early clinical stage. The aim of this preliminary study was to evaluate the usefulness of {sup 18}F-FDG PET in the early diagnosis of patients with colitis. We investigated five women (mean age 61.2{+-}12.1 years) who had been diagnosed as having colitis in an early clinical stage. In all but one of the patients, the diagnosis of colitis was based on biopsy. Magnetic resonance colonography, ultrasonography and colonoscopy were performed in all but one of the patients. Two women were identified as having collagenous colitis in an early clinical stage. Another two patients had eosinophilic colitis. The morphological imaging methods, magnetic resonance colonography and ultrasonography, yielded no suspicious findings, and the results of colonoscopy similarly showed no abnormalities. One patient had colitis due to bacterial infection. In all patients {sup 18}F-FDG PET showed a pathological increase in tracer uptake in the large bowel, suggestive of colitis. In four of the five patients, colitis was confirmed by histology, and in one, by bacterial analysis. {sup 18}F-FDG PET was able to detect colitis in an early clinical stage, when morphological imaging methods and colonoscopy were non-diagnostic. The early performance of {sup 18}F-FDG PET imaging in patients with possible colitis is encouraging. (orig.)

  9. Vision 20/20: Positron emission tomography in radiation therapy planning, delivery, and monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Parodi, Katia, E-mail: Katia.parodi@physik.uni-muenchen.de [Faculty of Physics, Department of Medical Physics, Ludwig Maximilians University Munich, Munich 85748 (Germany)

    2015-12-15

    Positron emission tomography (PET) is increasingly considered as an effective imaging method to support several stages of radiation therapy. The combined usage of functional and morphological imaging in state-of-the-art PET/CT scanners is rapidly emerging to support the treatment planning process in terms of improved tumor delineation, and to assess the tumor response in follow-up investigations after or even during the course of fractionated therapy. Moreover, active research is being pursued on new tracers capable of providing different insights into tumor function, in order to identify areas of the planning volume which may require additional dosage for improved probability of tumor control. In this respect, major progresses in the next years will likely concern the development and clinical investigation of novel tracers and image processing techniques for reliable thresholding and segmentation, of treatment planning and beam delivery approaches integrating the PET imaging information, as well as improved multimodal clinical instrumentation such as PET/MR. But especially in the rapidly emerging case of ion beam therapy, the usage of PET is not only limited to the imaging of external tracers injected to the patient. In fact, a minor amount of positron emitters is formed in nuclear fragmentation reactions between the impinging ions and the tissue, bearing useful information for confirmation of the delivered treatment during or after therapeutic irradiation. Different implementations of unconventional PET imaging for therapy monitoring are currently being investigated clinically, and major ongoing research aims at new dedicated detector technologies and at challenging applications such as real-time imaging and time-resolved in vivo verification of motion compensated beam delivery. This paper provides an overview of the different areas of application of PET in radiation oncology and discusses the most promising perspectives in the years to come for radiation therapy

  10. Localized fetomaternal hyperglycemia: spatial and kinetic definition by positron emission tomography.

    Directory of Open Access Journals (Sweden)

    Jianrong Yao

    Full Text Available BACKGROUND: Complex but common maternal diseases such as diabetes and obesity contribute to adverse fetal outcomes. Understanding of the mechanisms involved is hampered by difficulty in isolating individual elements of complex maternal states in vivo. We approached this problem in the context of maternal diabetes and sought an approach to expose the developing fetus in vivo to isolated hyperglycemia in the pregnant rat. METHODOLOGY AND PRINCIPAL FINDINGS: We hypothesized that glucose infused into the arterial supply of one uterine horn would more highly expose fetuses in the ipsilateral versus contralateral uterine horn. To test this, the glucose tracer [18F]fluorodeoxyglucose (FDG was infused via the left uterine artery. Regional glucose uptake into maternal tissues and fetuses was quantified using positron emission tomography (PET. Upon infusion, FDG accumulation began in the left-sided placentae, subsequently spreading to the fetuses. Over two hours after completion of the infusion, FDG accumulation was significantly greater in left compared to right uterine horn fetuses, favoring the left by 1.9+/-0.1 and 2.8+/-0.3 fold under fasted and hyperinsulinemic conditions (p<10(-11 n=32-35 and p<10(-12 n=27-45 respectively. By contrast, centrally administered [3H]-2-deoxyglucose accumulated equally between the fetuses of the two uterine horns. Induction of significant hyperglycemia (10(3 mg/dL localized to the left uterine artery was sustained for at least 48 hours while maternal euglycemia was maintained. CONCLUSIONS AND SIGNIFICANCE: This approach exposes selected fetuses to localized hyperglycemia in vivo, minimizing exposure of the mother and thus secondary effects. Additionally, a set of less exposed internal control fetuses are maintained for comparison, allowing direct study of the in vivo fetal effects of isolated hyperglycemia. Broadly, this approach can be extended to study a variety of maternal-sided perturbations suspected to directly

  11. The Silicon Photomultiplier for application to high-resolution Positron Emission Tomography

    Science.gov (United States)

    Herbert, D. J.; Moehrs, S.; D'Ascenzo, N.; Belcari, N.; Del Guerra, A.; Morsani, F.; Saveliev, V.

    2007-04-01

    Positron Emission Tomography (PET) for small animal studies requires high-resolution gamma cameras with high sensitivity. Traditionally, inorganic scintillators are used and, in recent times, coupled to position sensitive PMTs to achieve a higher resolution. Such PSPMTs are costly, operated at high voltage and have a relatively low packing fraction. However, their advantage, compared to current solid state photodetectors, is their high signal-to-noise ratio. The Silicon Photomultiplier (SiPM) is a silicon diode detector that shows great promise as a photodetector for scintillators and hence application in nuclear medicine imaging applications. The microcell MRS (Metal-Resistor-Semiconductor) structure of the SiPM leads to a self-quenching, Geiger-mode avalanche photodiode (GAPD), that produces a large gain (5×105) at low bias voltage (50 V) and proportional output for moderate photon flux. Such a compact silicon detector, with a performance similar to a PMT, is obviously well disposed to being developed into a close-packed array in order to have a position-sensitive detection surface. We propose a miniature, high-resolution camera for a small-animal PET imaging system that is based on such an array of SiPM. The design is based upon the classic Anger camera principle; each detector module consists of a continuous slab of scintillator, viewed by a matrix of SiPM. A detector head of 4×4 cm2 in area is proposed, constructed from three such modules of the continuous camera described above. The stacked layers would give the system intrinsic depth of interaction (DOI) information. A summary of measured SiPM performance and results of a simulation of the proposed camera, using the Monte Carlo package GEANT4, are presented. It is shown that using three layers of 5 mm thick LSO, gives an efficiency of 68% with maximum count rates in the front layers. Intrinsic spatial resolution of system.

  12. Radiation detector developments in medical applications: inorganic scintillators in positron emission tomography.

    Science.gov (United States)

    van Eijk, Carel W E

    2008-01-01

    In recent years, a number of new gamma-ray scintillators are commercially available. These scintillators are either derived from known scintillators, e.g. Lu1-xYxAlO3: Ce (LuYAP) from LuAlO3:Ce and Lu(2(1-x))Y2xSiO5:Ce (LYSO) from Lu2SiO5:Ce or are the result of new discoveries, e.g. LaCl3:Ce and LaBr3:Ce. The first two materials are primarily of interest because of the relatively high detection efficiency and fast response; LYSO has found application in time-of-flight (TOF) positron-emission tomography (TOF PET) and the LuYAP-LYSO combination is used in small-animal PET. The halide scintillators have an excellent energy resolution of approximately 3% at 662 keV and they have a relatively high light yield. LaBr3:Ce is being studied for application in TOF PET. At the same time, the search for and research on new scintillator materials are going on. For example, LuI3:Ce is a new material with a very high light yield (approximately 90,000 photons MeV(-1)). Other examples of new materials are (C6H13NH3)2PbI4 and (C3H7NH3)2PbBr4, organic-inorganic hybrid compounds, of which the former has a very fast sub-nanosecond response. The new scintillators show great promise for new developments in medical applications, in particular, for PET systems.

  13. PETPVC: a toolbox for performing partial volume correction techniques in positron emission tomography

    Science.gov (United States)

    Thomas, Benjamin A.; Cuplov, Vesna; Bousse, Alexandre; Mendes, Adriana; Thielemans, Kris; Hutton, Brian F.; Erlandsson, Kjell

    2016-11-01

    Positron emission tomography (PET) images are degraded by a phenomenon known as the partial volume effect (PVE). Approaches have been developed to reduce PVEs, typically through the utilisation of structural information provided by other imaging modalities such as MRI or CT. These methods, known as partial volume correction (PVC) techniques, reduce PVEs by compensating for the effects of the scanner resolution, thereby improving the quantitative accuracy. The PETPVC toolbox described in this paper comprises a suite of methods, both classic and more recent approaches, for the purposes of applying PVC to PET data. Eight core PVC techniques are available. These core methods can be combined to create a total of 22 different PVC techniques. Simulated brain PET data are used to demonstrate the utility of toolbox in idealised conditions, the effects of applying PVC with mismatched point-spread function (PSF) estimates and the potential of novel hybrid PVC methods to improve the quantification of lesions. All anatomy-based PVC techniques achieve complete recovery of the PET signal in cortical grey matter (GM) when performed in idealised conditions. Applying deconvolution-based approaches results in incomplete recovery due to premature termination of the iterative process. PVC techniques are sensitive to PSF mismatch, causing a bias of up to 16.7% in GM recovery when over-estimating the PSF by 3 mm. The recovery of both GM and a simulated lesion was improved by combining two PVC techniques together. The PETPVC toolbox has been written in C++, supports Windows, Mac and Linux operating systems, is open-source and publicly available.

  14. SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY STUDY OF REGIONAL CEREBRAL BLOOD FLOW IN PATIENTS WITH HEMISPATIAL NEGLECT

    Institute of Scientific and Technical Information of China (English)

    尹雅芙; 任艳; 李亚明

    2003-01-01

    Objective.To explore the correlations between the occurrence and severity of neglect and the region,range or extent of the decrease in regional cerebral blood flow(rCBF). Methods. Nineteen dextromanual patients who were diagnosed as unilateral stroke clinically and hemispatial neglect by a neglect test battery received single photon emission computed tomography(SPECT) scans. Results. On images,the damages of patients with neglect were seen most frequently in the frontal cortex,and then in turn in the parietal cortex,occipital cortex,temporal cortex,basal ganglia and thalamus. Most patients with neglect had two or more regions damaged. The most significant region was temporal-parietal-occipi-tal(TPO)junction. The correlation coefficient between rCBF and the severity of neglect was -0.34(t=-1.5,P>0.05),and that between the decrease percentage of rCBF and the severity of neglect was 0.34(t=1.47,P>0.05). The correlation coefficients between the range,number of foci,the flow deficit size and the severity of neglect were 0.71(t=4.13,P<0.01),0.70(t=4.07,P<0.01)and 0.64(t=3.40, P<0.01),respectively. Conclusions. The severity of neglect correlates with rCBF and the decrease percentage of rCBF insignificantly,but correlates positively with the range,number of foci and the flow deficit size significantly. Hemispatial neglect is caused by the damage of multiple sites and combined damage results in more severe neglect.

  15. Development of correction methods for variable pinhole single-photon emission computed tomography

    Science.gov (United States)

    Bae, S.; Bae, J.; Lee, H.; Lee, K.

    2016-02-01

    We propose a novel pinhole collimator in which the pinhole shape can be changed in real-time, and a new single-photon emission computed tomography (SPECT) system that utilizes this variable pinhole (VP) collimator. The acceptance angle and distance between the collimator and the object of VP SPECT are varied so that the optimum value of the region-of-interest (ROI) can be obtained for each rotation angle. Because of these geometrical variations, new correction methods are required for image reconstruction. In this study, we developed two correction methods. The first is the sensitivity-correction algorithm, which minimizes the variation of a system matrix caused by varying the acceptance angle for each rotation angle. The second is the acquisition-time-correction method, which reduces the variation of uniformity caused by varying the distance between the collimator and the object for each rotation angle. A 3D maximum likelihood expectation maximization (MLEM) algorithm was applied to image reconstruction, and two digital phantoms were studied to evaluate the resolution and sensitivity of the images obtained using the proposed methods. The images obtained by using the proposed correction methods show higher uniformity and resolution than those obtained without using these methods. In particular, the results of the resolution phantom study show that hot rods (0.8-mm-diameter) can be clearly distinguished using the proposed correction methods. A quantitative analysis of the ROI phantom revealed that the mean square error (MSE) was 0.42 without the acquisition-time-correction method, and 0.04 with the acquisition-time-correction method. The MSEs of the resolution phantom without and with the acquisition-time-correction method were calculated as 55.14 and 14.69, respectively.

  16. Molecular imaging of atherosclerotic lesions by positron emission tomography - can it meet the expectations?

    Science.gov (United States)

    Brammen, Lindsay; Steiner, Sabine; Berent, Robert; Sinzinger, Helmut

    2016-01-01

    Early non-invasive imaging of atherosclerosis and in particular the detection of lesions at risk with high specificity could significantly affect cardiovascular morbidity and mortality. Conventional nuclear medicine approaches, in particular using autologous radiolabeled lipoproteins, can be related to histopathological findings; however, they fail to identify lesions at risk. Positron emission tomography (PET) tracers with much better physical properties have been examined, the most detailed information being available for F-18-deoxyglucose (FDG) and F-18-sodium fluoride (NaF). These two approaches are sensitive to different biochemical mechanisms, i.e. inflammation and microcalcification. Initial enthusiasm, in particular for F-18-FDG, has disappeared, although for F-18-NaF there is some hope, but this is not a breakthrough. No tracer is available so far that is able to identify a specific characteristic of a lesion prone to rupture. Other PET tracers in the pipeline have been examined, mainly in experimental models and only a few in patients, but they failed to contribute significantly to early lesion discovery and do not support great expectations. The key question is: Do we understand what we see? Moreover, methodological problems, a lack of standardization of imaging protocols and aspects of quantification provide a wide range for potential future improvements. While monitoring a therapeutic intervention seems to be possible for both F-18-FDG and F-18-NaF, highly specific early identification of lesions at risk by PET imaging is still far away. As of today, PET is not ready for routine clinical judgment of atherosclerotic lesions at risk to rupture. Even if all these problems can be solved, radiation exposure will still remain a concern, in particular for repeated studies.

  17. A multiresolution image based approach for correction of partial volume effects in emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Boussion, N; Hatt, M; Lamare, F; Bizais, Y; Turzo, A; Rest, C Cheze-Le; Visvikis, D [INSERM U650, Laboratoire du Traitement de l' Information Medicale (LaTIM), CHU Morvan, Brest (France)

    2006-04-07

    Partial volume effects (PVEs) are consequences of the limited spatial resolution in emission tomography. They lead to a loss of signal in tissues of size similar to the point spread function and induce activity spillover between regions. Although PVE can be corrected for by using algorithms that provide the correct radioactivity concentration in a series of regions of interest (ROIs), so far little attention has been given to the possibility of creating improved images as a result of PVE correction. Potential advantages of PVE-corrected images include the ability to accurately delineate functional volumes as well as improving tumour-to-background ratio, resulting in an associated improvement in the analysis of response to therapy studies and diagnostic examinations, respectively. The objective of our study was therefore to develop a methodology for PVE correction not only to enable the accurate recuperation of activity concentrations, but also to generate PVE-corrected images. In the multiresolution analysis that we define here, details of a high-resolution image H (MRI or CT) are extracted, transformed and integrated in a low-resolution image L (PET or SPECT). A discrete wavelet transform of both H and L images is performed by using the 'a trous' algorithm, which allows the spatial frequencies (details, edges, textures) to be obtained easily at a level of resolution common to H and L. A model is then inferred to build the lacking details of L from the high-frequency details in H. The process was successfully tested on synthetic and simulated data, proving the ability to obtain accurately corrected images. Quantitative PVE correction was found to be comparable with a method considered as a reference but limited to ROI analyses. Visual improvement and quantitative correction were also obtained in two examples of clinical images, the first using a combined PET/CT scanner with a lymphoma patient and the second using a FDG brain PET and corresponding T1

  18. Detection of occult disease in breast cancer using fluorodeoxyglucose camera-based positron emission tomography.

    Science.gov (United States)

    Pecking, A P; Mechelany-Corone, C; Bertrand-Kermorgant, F; Alberini, J L; Floiras, J L; Goupil, A; Pichon, M F

    2001-10-01

    An isolated increase of blood tumor marker CA 15.3 in breast cancer is considered a sensitive indicator for occult metastatic disease but by itself is not sufficient for initiating therapeutic intervention. We investigated the potential of camera-based positron emission tomography (PET) imaging using [18F]-fluorodeoxyglucose (FDG) to detect clinically occult recurrences in 132 female patients (age, 35-69 years) treated for breast cancer, all presenting with an isolated increase in blood tumor marker CA 15.3 without any other evidence of metastatic disease. FDG results were correlated to pathology results or to a sequentially guided conventional imaging method. One hundred nineteen patients were eligible for correlations. Positive FDG scans were obtained for 106 patients, including 89 with a single lesion and 17 with 2 or more lesion. There were 92 true-positive and 14 false-positive cases, 10 of which became true positive within 1 year. Among the 13 negative cases, 7 were false negative and 6 were true negative. Camera-based PET using FDG has successfully identified clinically occult disease with an overall sensitivity of 93.6% and a positive predictive value of 96.2%. The smallest detected size was 6 mm for a lymph node metastasis (tumor to nontumor ratio, 4:2). FDG camera-based PET localized tumors in 85.7% of cases suspected for clinically occult metastatic disease on the basis of a significant increase in blood tumor marker. A positive FDG scan associated with an elevated CA 15.3 level is most consistent with metastatic relapse of breast cancer.

  19. Whole-body energy mapping under physical exercise using positron emission tomography.

    Science.gov (United States)

    Iemitsu, M; Itoh, M; Fujimoto, T; Tashiro, M; Nagatomi, R; Ohmori, H; Ishii, K

    2000-12-01

    We attempted to visualize dynamic adjustment of glucose utilization in humans in the whole-body organs during physical exercise by using three-dimensional positron emission tomography (3D-PET) and [18F]-2-fluoro-deoxy-glucose (FDG). Twelve healthy male volunteers collaborated on the study; six subjects were assigned to the resting control group (C) and the other six to the running group (E). Group E subjects performed running on a flat road for 35 min. After 15 min of running, subjects injected FDG and kept on running thereafter for another 20 min. Group C subjects sat on a comfortable chair in a quiet room for 35 min after the injection of FDG. After scanning by PET, the regions of interest (ROIs) were manually set on brain, heart, thorax, abdomen, lower extremities, and the rest of the body on the corresponding transaxial images. The uptake of FDG in each region was evaluated as the % fraction of FDG accumulation relative to the total amount of whole-body accumulation. The results revealed increase of FDG uptake after running in the lower leg muscles from 24.6 +/- 9.5% to 43.1 +/- 4.7% and in the heart from 2.3 +/- 0.4% to 2.8 +/- 0.6%. The differences were significant (P body. FDG uptake in the abdominal region reduced from 37.3 +/- 7.2% to 19.7 +/- 4.9%. However, FDG uptake in the brain remained stable, i.e., 11.9 +/- 2.8% at rest and 10.3 +/- 2.5% after exercise. Thus, 3D-PET is a tool to visualize the dynamic adjustment of energy consumption during physical exercise in humans.

  20. Imaging glucose metabolism in perfluorocarbon-perfused hepatocyte bioreactors using positron emission tomography.

    Science.gov (United States)

    Nieuwoudt, Martin; Wiggett, Scholtz; Malfeld, Susan; van der Merwe, Schalk W

    2009-01-01

    In vitro hepatocyte bioreactor functionality depends particularly on maintaining appropriate oxygen levels and exposure to nonparenchymal cells. An attractive solution without immunological consequences to the patient is incorporating a perfluorocarbon oxygen carrier in the circulating medium and co-culturing hepatocytes with stellate cells. Since bioreactors are normally sealed sterile units, demonstrating metabolic functionality is hindered by limited access to the cells after their aggregation in the matrix. A novel possibility is to use positron emission tomography (PET) to image cellular radioactive glucose uptake under O(2)-limited conditions. In this study, primary cell isolation procedures were carried out on eight pigs. Pairs of cell-seeded and cell-free (control) bioreactors with and without perfluorocarbon were cultured under identical conditions and were oxygenated using hypoxic (5% O(2)) and ambient (20% O(2)) gas mixes. Sixteen PET scans were conducted 24 h after cell isolation, the same timescale as that involved in treating a liver failure patient with a primary-cell bioreactor. In all cases, cell-seeded bioreactors without perfluorocarbon were more radioactive, i.e., were more glycolytic, than those with perfluorocarbon. This difference was significant in the hypoxic pair of bioreactors but not in the ambient pair of bioreactors. Additionally, in the same hypoxic bioreactors, circulating extracellular steady-state glucose levels were significantly lower and lactate levels were higher than those in the ambient bioreactors. Similar findings have been made in other in vitro hepatocyte studies investigating the effects of perfluorocarbons. PET is attractive for studying in situ O(2)-dependent bioreactor metabolism because of its visual and numerically quantifiable outputs. Longer-term metabolic studies (e.g., 5-10 days) investigating the effect of perfluorocarbon on bioreactor longevity will complement these findings in the future.

  1. Clinical utility of 11C-flumazenil positron emission tomography in intractable temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Padma M

    2004-10-01

    Full Text Available BACKGROUND: 11C-flumazenil (FMZ positron emission tomography (PET is a new entrant into the armamentarium for pre-surgical evaluation of patients with intractable temporal lobe epilepsy (TLE. AIMS: To analyze the clinical utility of FMZ PET to detect lesional and remote cortical areas of abnormal benzodiazepine receptor binding in relation to magnetic resonance imaging (MRI, 2-Deoxy-2 [18F] fluoro-D-glucose, (18F FDG PET, electrophysiological findings and semiology of epilepsy in patients with intractable TLE. MATERIALS AND METHODS: Patients underwent a high resolution MRI, prolonged Video-EEG monitoring before 18F FDG and 11C FMZ PET studies. Regional cortical FMZ PET abnormalities were defined on co-registered PET images using an objective method based on definition of areas of abnormal asymmetry (asymmetry index {AI}>10%. SETTINGS AND DESIGN: Prospective. STATISTICAL ANALYSIS: Student′s "t" test. RESULTS: Twenty patients (Mean age: 35.2 years [20-51]; M:F=12:8 completed the study. Mean age at seizure onset was 10.3 years (birth-38 years; mean duration, 23.9 years (6-50 years. Concordance with the MRI lesion was seen in 10 patients (nine with hippocampal sclerosis and one with tuberous sclerosis. In the other 10, with either normal or ambiguous MRI findings, FMZ and FDG uptake were abnormal in all, concordant with the electrophysiological localization of the epileptic foci. Remote FMZ PET abnormalities (n=18 were associated with early age of seizure onset (P=0.005 and long duration of epilepsy (P=0.01. CONCLUSIONS: FMZ-binding asymmetry is a sensitive method to detect regions of epileptic foci in patients with intractable TLE.

  2. Positron emission tomography thyroid incidentaloma: Is it different in Indian subcontinent?

    Directory of Open Access Journals (Sweden)

    R Vaish

    2016-01-01

    Full Text Available Background: Positron emission tomography (PET forms an integral part in work-up and follow-up of various malignancies. With the increased use of PET in oncology, finding of an incidental focal thyroid uptake (incidentaloma is not unusual and presents a diagnostic challenge. Aim: The aim of the following study is to evaluate the frequency and radio-pathologic correlation of focal 18-fluoro deoxyglucose uptake (FDG on PET within the thyroid from a large series. Materials and Methods: Retrospective review of 37,000 consecutive patients who underwent FDG-PET at tertiary cancer center in India. Radiological, pathological, PET scan and follow-up details were evaluated. Statistical analyzes were carried out using Mann Whitney test and Pearson correlation. Results: Abnormal thyroid uptake was seen in 78 (0.2% patients. Nearly 61 (0.16% scans had focal and 17 (0.04% had diffuse FDG uptake. A total of 57 patients with focal uptake were available for further evaluation. No further evaluation was done in 24 (42.1% patients who had advanced index malignancy. Of the remaining 33 patients 26 were benign and seven were a cause for concern (four primary thyroid cancers, one follicular neoplasm with hurthle cell change and two metastatic cancers. There was no significant correlation in Standardized uptake value (SUV max of benign and malignant lesion (P = 0.5 on Mann Whitney or size (r = 0.087 Pearson correlation co-efficient P= 0.667. Conclusion: Incidence of PET incidentaloma is low in this large cohort of Indian patients. Nearly 27% of focal incidentaloma were malignant. There was no correlation between the SUVmax, size and malignancy.

  3. A quantitative model for the in vivo assessment of drug binding sites with positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Mintun, M.A.; Raichle, M.E.; Kilbourn, M.R.; Wooten, G.F.; Welch, M.J.

    1984-03-01

    We propose an in vivo method for use with positron emission tomography (PET) that results in a quantitative characterization of neuroleptic binding sites using radiolabeled spiperone. The data are analyzed using a mathematical model that describes transport, nonspecific binding, and specific binding in the brain. The model demonstrates that the receptor quantities Bmax (i.e., the number of binding sites) and KD-1 (i.e., the binding affinity) are not separably ascertainable with tracer methodology in human subjects. We have, therefore, introduced a new term, the binding potential, equivalent to the product BmaxKD-1, which reflects the capacity of a given tissue, or region of a tissue, for ligand-binding site interaction. The procedure for obtaining these measurements is illustrated with data from sequential PET scans of baboons after intravenous injection of carrier-added (18F)spiperone. From these data we estimate the brain tissue nonspecific binding of spiperone to be in the range of 94.2 to 95.3%, and the regional brain spiperone permeability (measured as the permeability-surface area product) to be in the range of 0.025 to 0.036 cm3/(s X ml). The binding potential of the striatum ranged from 17.4 to 21.6; these in vivo estimates compare favorably to in vitro values in the literature. To our knowledge this represents the first direct evidence that PET can be used to characterize quantitatively, locally and in vivo, drug binding sites in brain. The ability to make such measurements with PET should permit the detailed investigation of diseases thought to result from disorders of receptor function.

  4. Optimised motion tracking for positron emission tomography studies of brain function in awake rats.

    Directory of Open Access Journals (Sweden)

    Andre Z Kyme

    Full Text Available Positron emission tomography (PET is a non-invasive molecular imaging technique using positron-emitting radioisotopes to study functional processes within the body. High resolution PET scanners designed for imaging rodents and non-human primates are now commonplace in preclinical research. Brain imaging in this context, with motion compensation, can potentially enhance the usefulness of PET by avoiding confounds due to anaesthetic drugs and enabling freely moving animals to be imaged during normal and evoked behaviours. Due to the frequent and rapid motion exhibited by alert, awake animals, optimal motion correction requires frequently sampled pose information and precise synchronisation of these data with events in the PET coincidence data stream. Motion measurements should also be as accurate as possible to avoid degrading the excellent spatial resolution provided by state-of-the-art scanners. Here we describe and validate methods for optimised motion tracking suited to the correction of motion in awake rats. A hardware based synchronisation approach is used to achieve temporal alignment of tracker and scanner data to within 10 ms. We explored the impact of motion tracker synchronisation error, pose sampling rate, rate of motion, and marker size on motion correction accuracy. With accurate synchronisation (20 Hz, and a small head marker suitable for awake animal studies, excellent motion correction results were obtained in phantom studies with a variety of continuous motion patterns, including realistic rat motion (<5% bias in mean concentration. Feasibility of the approach was also demonstrated in an awake rat study. We conclude that motion tracking parameters needed for effective motion correction in preclinical brain imaging of awake rats are achievable in the laboratory setting. This could broaden the scope of animal experiments currently possible with PET.

  5. Positron emission tomography reporter genes and reporter probes: gene and cell therapy applications.

    Science.gov (United States)

    Yaghoubi, Shahriar S; Campbell, Dean O; Radu, Caius G; Czernin, Johannes

    2012-01-01

    Positron emission tomography (PET) imaging reporter genes (IRGs) and PET reporter probes (PRPs) are amongst the most valuable tools for gene and cell therapy. PET IRGs/PRPs can be used to non-invasively monitor all aspects of the kinetics of therapeutic transgenes and cells in all types of living mammals. This technology is generalizable and can allow long-term kinetics monitoring. In gene therapy, PET IRGs/PRPs can be used for whole-body imaging of therapeutic transgene expression, monitoring variations in the magnitude of transgene expression over time. In cell or cellular gene therapy, PET IRGs/PRPs can be used for whole-body monitoring of therapeutic cell locations, quantity at all locations, survival and proliferation over time and also possibly changes in characteristics or function over time. In this review, we have classified PET IRGs/PRPs into two groups based on the source from which they were derived: human or non-human. This classification addresses the important concern of potential immunogenicity in humans, which is important for expansion of PET IRG imaging in clinical trials. We have then discussed the application of this technology in gene/cell therapy and described its use in these fields, including a summary of using PET IRGs/PRPs in gene and cell therapy clinical trials. This review concludes with a discussion of the future direction of PET IRGs/PRPs and recommends cell and gene therapists collaborate with molecular imaging experts early in their investigations to choose a PET IRG/PRP system suitable for progression into clinical trials.

  6. Positron Emission Tomography Reporter Genes and Reporter Probes: Gene and Cell Therapy Applications

    Directory of Open Access Journals (Sweden)

    Shahriar S. Yaghoubi, Dean O. Campbell, Caius G. Radu, Johannes Czernin

    2012-01-01

    Full Text Available Positron emission tomography (PET imaging reporter genes (IRGs and PET reporter probes (PRPs are amongst the most valuable tools for gene and cell therapy. PET IRGs/PRPs can be used to non-invasively monitor all aspects of the kinetics of therapeutic transgenes and cells in all types of living mammals. This technology is generalizable and can allow long-term kinetics monitoring. In gene therapy, PET IRGs/PRPs can be used for whole-body imaging of therapeutic transgene expression, monitoring variations in the magnitude of transgene expression over time. In cell or cellular gene therapy, PET IRGs/PRPs can be used for whole-body monitoring of therapeutic cell locations, quantity at all locations, survival and proliferation over time and also possibly changes in characteristics or function over time. In this review, we have classified PET IRGs/PRPs into two groups based on the source from which they were derived: human or non-human. This classification addresses the important concern of potential immunogenicity in humans, which is important for expansion of PET IRG imaging in clinical trials. We have then discussed the application of this technology in gene/cell therapy and described its use in these fields, including a summary of using PET IRGs/PRPs in gene and cell therapy clinical trials. This review concludes with a discussion of the future direction of PET IRGs/PRPs and recommends cell and gene therapists collaborate with molecular imaging experts early in their investigations to choose a PET IRG/PRP system suitable for progression into clinical trials.

  7. A method for comparing intra-tumoural radioactivity uptake heterogeneity in preclinical positron emission tomography studies

    Energy Technology Data Exchange (ETDEWEB)

    Grafström, Jonas; Ahlzén, Hanna-Stina [Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17177 Stockholm (Sweden); Stone-Elander, Sharon [Department of Clinical Neuroscience, Karolinska Institutet, SE-17176 Stockholm (Sweden); PET Radiochemistry, Neuroradiology Department, Karolinska University Hospital, SE-17176 Stockholm (Sweden)

    2015-09-08

    Non-uniformity influences the interpretation of nuclear medicine based images and consequently their use in treatment planning and monitoring. However, no standardised method for evaluating and ranking heterogeneity exists. Here, we have developed a general algorithm that provides a ranking and a visualisation of the heterogeneity in small animal positron emission tomography (PET) images. The code of the algorithm was written using the Matrix Laboratory software (MATLAB). Parameters known to influence the heterogeneity (distances between deviating peaks, gradients and size compensations) were incorporated into the algorithm. All data matrices were mathematically constructed in the same format with the aim of maintaining overview and control. Histograms visualising the spread and frequency of contributions to the heterogeneity were also generated. The construction of the algorithm was tested using mathematically generated matrices and by varying post-processing parameters. It was subsequently applied in comparisons of radiotracer uptake in preclinical images in human head and neck carcinoma and endothelial and ovarian carcinoma xenografts. Using the developed algorithm, entire tissue volumes could be assessed and gradients could be handled in an indirect manner. Similar-sized volumes could be compared without modifying the algorithm. Analyses of the distribution of different tracers gave results that were generally in accordance with single plane preclinical images, indicating that it could appropriately handle comparisons of targeting vs. non-targeting tracers and also for different target levels. Altering the reconstruction algorithm, pixel size, tumour ROI volumes and lower cut-off limits affected the calculated heterogeneity factors in expected directions but did not reverse conclusions about which tumour was more or less heterogeneous. The algorithm constructed is an objective and potentially user-friendly tool for one-to-one comparisons of heterogeneity in

  8. A novel image reconstruction methodology based on inverse Monte Carlo analysis for positron emission tomography

    Science.gov (United States)

    Kudrolli, Haris A.

    2001-04-01

    A three dimensional (3D) reconstruction procedure for Positron Emission Tomography (PET) based on inverse Monte Carlo analysis is presented. PET is a medical imaging modality which employs a positron emitting radio-tracer to give functional images of an organ's metabolic activity. This makes PET an invaluable tool in the detection of cancer and for in-vivo biochemical measurements. There are a number of analytical and iterative algorithms for image reconstruction of PET data. Analytical algorithms are computationally fast, but the assumptions intrinsic in the line integral model limit their accuracy. Iterative algorithms can apply accurate models for reconstruction and give improvements in image quality, but at an increased computational cost. These algorithms require the explicit calculation of the system response matrix, which may not be easy to calculate. This matrix gives the probability that a photon emitted from a certain source element will be detected in a particular detector line of response. The ``Three Dimensional Stochastic Sampling'' (SS3D) procedure implements iterative algorithms in a manner that does not require the explicit calculation of the system response matrix. It uses Monte Carlo techniques to simulate the process of photon emission from a source distribution and interaction with the detector. This technique has the advantage of being able to model complex detector systems and also take into account the physics of gamma ray interaction within the source and detector systems, which leads to an accurate image estimate. A series of simulation studies was conducted to validate the method using the Maximum Likelihood - Expectation Maximization (ML-EM) algorithm. The accuracy of the reconstructed images was improved by using an algorithm that required a priori knowledge of the source distribution. Means to reduce the computational time for reconstruction were explored by using parallel processors and algorithms that had faster convergence rates

  9. Functional imaging in bulk tissue specimens using optical emission tomography: fluorescence preservation during optical clearing

    Science.gov (United States)

    Sakhalkar, H. S.; Dewhirst, M.; Oliver, T.; Cao, Y.; Oldham, M.

    2007-04-01

    Optical emission computed tomography (optical-ECT) is a technique for imaging the three-dimensional (3D) distribution of fluorescent probes in biological tissue specimens with high contrast and spatial resolution. In optical-ECT, functional information can be imaged by (i) systemic application of functional labels (e.g. fluorophore labelled proteins) and/or (ii) endogenous expression of fluorescent reporter proteins (e.g. red fluorescent protein (RFP), green fluorescent protein (GFP)) in vivo. An essential prerequisite for optical-ECT is optical clearing, a procedure where tissue specimens are made transparent to light by sequential perfusion with fixing, dehydrating and clearing agents. In this study, we investigate clearing protocols involving a selection of common fixing (4% buffered paraformaldehyde (PFA), methanol and ethanol), dehydrating (methanol and ethanol) and clearing agents (methyl salicylate and benzyl-alcohol-benzyl-benzoate (BABB)) in order to determine a 'fluorescence friendly' clearing procedure. Cell culture experiments were employed to optimize the sequence of chemical treatments that best preserve fluorescence. Texas red (TxRed), fluorescein isothiocyanate (FITC), RFP and GFP were tested as fluorophores and fluorescent reporter proteins of interest. Fluorescent and control cells were imaged on a microscope using a DSred2 and FITC filter set. The most promising clearing protocols of cell culture experiments were applied to whole xenograft tumour specimens, to test their effectiveness in large unsectioned samples. Fluorescence of TxRed/FITC fluorophores was not found to be significantly affected by any of the test clearing protocols. RFP and GFP fluorescence, however, was found to be significantly greater when cell fixation was in ethanol. Fixation in either PFA or methanol resulted in diminished fluorescence. After ethanol fixation, the RFP and GFP fluorescence proved remarkably robust to subsequent exposure to either methyl salicylate or BABB

  10. Voluminal modelling for the characterization of wastes packages by gamma emission computed tomography; Modelisation volumique pour la caracterisation de colis de dechets par tomographie d'emission gamma

    Energy Technology Data Exchange (ETDEWEB)

    Pettier, J.L.; Thierry, R. [CEA Cadarache, Dept. d' Entreposage et de Stockage des Dechets, 13 - Saint-Paul-lez-Durance (France)

    2001-07-01

    The aim of this work is to model the measurement process used for multi-photon emission computed tomography on nuclear waste drum. Our model MEPHISTO (Multi-Energy PHoton Imagery through Segmented TOmography) takes into account all phenomena influencing gamma emergent flux and high resolution spectrometric measurements using an HpGe detector through a collimator aperture. These phenomena are absorption and Compton scattering of gamma photons in waste drum, geometrical blur, spatial and energetic response of the detector. The analysis of results shows better localisation and quantification performances compared with a Ray-Driven method. It proves the importance of an accurate modelization of collimated measurements to reduce noise and stabilize iterative image reconstructions. (authors)

  11. Virtual bronchoscopy using image data sets from positron-emission-tomography and computed-tomography; Virtuelle Bronchoskopie mit Positronenemissions- und Computertomographie-Bilddaten

    Energy Technology Data Exchange (ETDEWEB)

    Englmeier, K.H.; Jovanovic, A.; Muehling, M.; Seemann, M.D. [Nuklearmedizinische Klinik und Poliklinik, rechts der Isar, Technische Univ. Muenchen (DE). Inst. fuer Medizinische Informatik (Germany)

    2006-07-01

    Cancer is the second leading cause of death in the western world. Early diagnosis and targeted therapy provide the basis for planning effective treatment. Diseases like cancer generally begin with alterations at the molecular level. When the number of affected cells reaches the threshold for anatomical change, the disease can already be so advanced that it is too late for successful treatment. Equally, morphological change is not necessarily associated with malignancy. Diagnosis and staging of cancer, and evaluation of therapeutic success, depend today to a large extent on imaging techniques like computed tomography (CT) and magnetic resonance tomography (MRT). However, these can only be used to identify anatomical changes in lesions. Increasingly, imaging techniques like positron emission tomography (PET) are used that are based at the molecular level. Functional imaging techniques detect functional changes in tissues that play a role in the diagnosis and staging of the disease. Virtual reality techniques, especially virtual endoscopy, have also become more important in PET-CT diagnostics. On the one hand, these methods enable simultaneous visualisation of morphological and metabolic relationships; on the other hand, the enormous amount of image data from PET-CT can be made understandable in an intuitive form with the aid of endoluminal three-dimensional (3-D) images and scenes. The prerequisite is that the image data from PET and CT are segmented after fusion using image analysis techniques and subsequently projected using a 3-D imaging system and virtual reality techniques. Together with the Department of Nuclear Medicine of the Technical University, Munich, a system has been developed for virtual bronchoscopy that is intended to improve diagnostic precision in cases of bronchial carcinoma. (orig.)

  12. Head sinuses, melon, and jaws of bottlenose dolphins, Tursiops truncatus, observed with computed tomography structural and single photon emission computed tomography functional imaging

    Science.gov (United States)

    Ridgway, Sam; Houser, Dorian; Finneran, James J.; Carder, Don; van Bonn, William; Smith, Cynthia; Hoh, Carl; Corbeil, Jacqueline; Mattrey, Robert

    2003-04-01

    The head sinuses, melon, and lower jaws of dolphins have been studied extensively with various methods including radiography, chemical analysis, and imaging of dead specimens. Here we report the first structural and functional imaging of live dolphins. Two animals were imaged, one male and one female. Computed tomography (CT) revealed extensive air cavities posterior and medial to the ear as well as between the ear and sound-producing nasal structures. Single photon emission computed tomography (SPECT) employing 50 mCi of the intravenously injected ligand technetium [Tc-99m] biscisate (Neurolite) revealed extensive and uptake in the core of the melon as well as near the pan bone area of the lower jaw. Count density on SPECT images was four times greater in melon as in the surrounding tissue and blubber layer suggesting that the melon is an active rather than a passive tissue. Since the dolphin temporal bone is not attached to the skull except by fibrous suspensions, the air cavities medial and posterior to the ear as well as the abutment of the temporal bone, to the acoustic fat bodies of each lower jaw, should be considered in modeling the mechanism of sound transmission from the environment to the dolphin ear.

  13. Fluorodeoxyglucose positron emission tomography-computed tomography: a novel approach for the diagnosis of cholecystitis for equivocal diagnoses after ultrasound imaging.

    Science.gov (United States)

    Nasseri, Yosef; Ourian, Ariel J; Waxman, Alan; D'Angolo, Alessandro; Thomson, Louise E; Margulies, Daniel R

    2012-10-01

    Although hepatobiliary iminodiacetic acid (HIDA) scan is often used when the diagnosis of cholecystitis remains questionable after ultrasound, it carries a high false-positive rate and has other limitations. Fluorodeoxyglucose positron emission tomography-computed tomography (18FDG PET-CT) has recently gained enthusiasm for its ability to detect infection and inflammation. In this study, we evaluate the accuracy of 18FDG PET-CT in diagnosing cholecystitis. Nineteen patients with suspected cholecystitis (Group S) underwent PET-CT and 10 had positive PET-CT findings. Of these 10, nine underwent cholecystectomies, and pathology confirmed cholecystitis in all nine. One patient was managed nonoperatively as a result of multiple comorbidities. Of the nine patients with negative PET-CT, six were managed nonoperatively, safely discharged, and had no readmissions at 3-month follow-up. The other three patients with negative PET-CT underwent cholecystectomies, and two showed no cholecystitis on pathology. The third had mild to moderate cholecystitis with focal mucosal erosion/ulceration without gallbladder wall thickening on pathology. 18FDG PET-CT detected gallbladder inflammation in all but one patient with pathology-proven cholecystitis with a sensitivity and specificity of 0.90 and 1.00, respectively. 18FDG-PET-CT appears to be a promising, rapid, direct, and accurate test in diagnosing cholecystitis and could replace HIDA scan in cases that remain equivocal after ultrasound.

  14. F-8 sodium fluoride position emission tomography/computed tomography for detection of thyroid cancer bone metastasis compared with bone scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun Jong; Lee, Won Woo; Park, So Yeon; Kim, Sang Eun [Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2016-04-15

    The aim of the study was to compare the diagnostic performances of F-18 sodium fluoride positron emission tomography/computed tomography (bone PET/CT) and bone scintigraphy (BS) for the detection of thyroid cancer bone metastasis. We retrospectively enrolled 6 thyroid cancer patients (age = 44.7 ± 9.8 years, M:F = 1:5, papillary:follicular = 2:4) with suspected bone metastatic lesions in the whole body iodine scintigraphy or BS, who subsequently underwent bone PET/CT. Pathologic diagnosis was conducted for 4 lesions of 4 patients. Of the 17 suspected bone lesions, 10 were metastatic and 7 benign. Compared to BS, bone PET/CT exhibited superior sensitivity (10/10 = 100% vs. 2/10 = 20%, p = 0.008), and accuracy (14/17 = 82.4% vs. 7/17 = 41.2%, p < 0.025). The specificity (4/7 = 57.1%) of bone PET/CT was not significantly different from that of BS (5/7 = 71.4%, p > 0.05). Bone PET/CT may be more sensitive and accurate than BS for the detection of thyroid cancer bone metastasis.

  15. Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography evaluation of subcutaneous panniculitis-like T cell lymphoma and treatment response

    Science.gov (United States)

    Gorodetskiy, Vadim R; Mukhortova, Olga V; Aslanidis, Irakli P; Klapper, Wolfram; Probatova, Natalya A

    2016-01-01

    Subcutaneous panniculitis-like T cell lymphoma (SPTCL) is a very rare variant of non-Hodgkin’s lymphoma. Currently, there is no standard imaging method for staging of SPTCL nor for assessment of treatment response. Here, we describe our use of fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for staging and monitoring of treatment response in 3 cases of SPTCL. Primary staging by PET/CT showed that all 3 patients had multiple foci in the subcutaneous fat tissue, with SUVmax from 10.5 to 14.6. Involvement of intra-abdominal fat with high SUVmax was identified in 2 of the patients. Use of the triple drug regimen of gemcitabine, cisplatin and methylprednisolone (commonly known as “GEM-P”) as first-line therapy or second-line therapy facilitated complete metabolic response for all 3 cases. FDG PET/CT provides valuable information for staging and monitoring of treatment response and can reveal occult involvement of the intra-abdominal visceral fat. High FDG uptake on pre-treatment PET can identify patients with aggressive disease and help in selection of first-line therapy. PMID:27672640

  16. Preoperative lymph-node staging of invasive urothelial bladder cancer with 18F-fluorodeoxyglucose positron emission tomography/computed axial tomography and magnetic resonance imaging

    DEFF Research Database (Denmark)

    Jensen, Thor Knak; Holt, Per; Gerke, Oke

    2011-01-01

    investigated the value of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed axial tomography (¹⁸F-FDG PET/CT) and magnetic resonance imaging (MRI) for preoperative N staging of bladder cancer. Material and methods. From June 2006 to January 2008, 48 consecutive patients diagnosed with bladder...... cancer were referred to preoperative staging including MRI and ¹⁸F-FDG PET/CT. Eighteen out of 48 patients underwent radical cystoprostatectomy including removal of lymph nodes for histology, and were included in the study. Values of ¹⁸F-FDG PET/CT and MRI for regional N staging were compared...... to histopathology findings, the gold standard. Results. ¹⁸F-FDG PET/CT and MRI were performed in 18 patients. The specificities for detection of lymph-node metastases for MRI and ¹⁸F-FDG PET/CT were 80% (n = 15) and 93.33% (n = 15), respectively. The negative predictive values were 80% (n = 15) and 87.5% (n = 16...

  17. Whole-body 18F-fluorodeoxyglucose positron emission tomography/computed tomography images before and after chemotherapy for Kaposi sarcoma and highly active antiretrovirus therapy.

    Science.gov (United States)

    Morooka, Miyako; Ito, Kimiteru; Kubota, Kazuo; Minamimoto, Ryogo; Shida, Yoshitaka; Hasuo, Kanehiro; Ito, Tateki; Tasato, Daisuke; Honda, Haruhito; Teruya, Katsuji; Kikuchi, Yoshimi; Ohtomo, Kuni

    2010-12-01

    Kaposi sarcoma is an acquired immunodeficiency syndrome-related disease that mainly involves the skin, gastrointestinal gut, and lungs. Whole-body 18F-fluorodeoxyglucose-positron emission tomography and computed tomography (FDG-PET/CT) scanning is useful for simultaneous detection of multiple lesions of Kaposi sarcoma. We present a 67-year-old man with a history of infection with human immunodeficiency virus who presented with numerous cutaneous lesions. FDG-PET/CT images showed lesions in the skin, lung, and lymph nodes. The gastrointestinal lesions were detected using gastric fiberscopy (GF) and colon fiberscopy (CF). After Kaposi sarcoma therapy, the uptake in the lesions of the skin, lung, and lymph nodes decreased, but new lesions were detected in the pancreas and lumbar spine. He had pancreatitis and Candida spondilitis. Whole-body FDG-PET/CT is useful for detecting lesions and determining the extension to which the disease has spread, adding the gastrointestinal lesions by GF and CF. After therapy, FDG-PET/CT can be used to demonstrate which lesions remain active and to determine the overall response to treatment. In this case, we show how useful FDG-PET/CT is and how difficult it is to treat Kaposi sarcoma.

  18. Value of Positron Emission Tomography/Computed Tomography (PET-CT) in Suspected Non-small Cell Lung Cancer Recurrence and Impact on Patient Management

    Science.gov (United States)

    Beslic, Nermina; Sadija, Amera; Ceric, Timur; Milardovic, Renata; Ceric, Sejla; Cavaljuga, Semra

    2016-01-01

    Introduction: Positron emission tomography/computed tomography (PET-CT) is very sensitive for diagnosis of recurrent NSCLC and has a significant impact on change of management. Preliminary data suggest superiority of PET-CT comparing to CT alone for lung cancer restaging. Materials and methods: This is a retrospective study which aim is to validate usage of PET-CT in suspected non-small cell lung carcinoma recurrence and its impact on further patient management. Total number of 31 patients with non-small cell lung carcinoma and uncertain diagnosis of recurrent disease or its extent after routine clinical and CT work-up were enrolled in this study. Discussion: We found in our study that PET-CT diagnosed recurrent disease in 65% of patients who were previously presented with an indeterminante CT. In 85% of patients there were change in further management. Conclusion: We suggest that PET should be performed on patients who have suspected relapse after potentially curative treatment, particularly if active treatment is being considered. PET-CT improved the diagnosis of recurrent NSCLC and this resulted in a significant impact and change in further patient management. PMID:27708496

  19. Co-registered positron emission tomography/computed tomography and gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid magnetic resonance imaging features of multiple angiosarcoma of the liver.

    Science.gov (United States)

    Kamatani, Takashi; Iguchi, Hiroyoshi; Okada, Takemichi; Yamazaki, Hitoshi; Tsunoda, Hidekazu; Watanabe, Masaaki; Oda, Masaya; Ohbu, Makoto; Yokomori, Hiroaki

    2014-10-01

    Hepatic angiosarcoma is a very rare disease, accounting for only 2% of primary liver malignancy. An 82-year-old man was admitted to our hospital because of jaundice and weight loss. Computed tomography (CT) and magnetic resonance imaging (MRI) showed diffuse and multiple space-occupying lesions. On gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI, the tumor was not enhanced intensely in the arterial phase following contrast injection, and was then gradually enhanced homogeneously. In the delayed phase and hepatobiliary phase, the tumor was completely washed out. Whole-body (18) F-fluorodeoxyglucose positron emission tomography (FDG-PET)/CT fusion scanning confirmed metabolic activity with maximum uptake value of 3.64 in the lesions. A liver biopsy showed spindle-shaped tumor cells proliferating along sinusoids, with elongated and hyperchromatic nuclei. Immunohistochemical studies showed tumor cells positive for von Willebrand factor and CD34. These findings were consistent with angiosarcoma of the liver. This case report is the first description of co-registered FDG-PET/CT images and Gd-EOB-DTPA-enhanced MRI of primary hepatic angiosarcoma.

  20. Therapeutic impact of [{sup 18}F]fluoride positron-emission tomography/computed tomography on patients with unclear foot pain

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Dorothee Rita; Hesselmann, Rolf; Johayem, Anass; Hany, Thomas F.; Schulthess, Gustav K. von; Strobel, Klaus [University Hospital of Zurich, Department of Nuclear Medicine, Zurich (Switzerland); Maquieira, Gerardo J.; Espinosa, Norman [University of Zurich, Foot and Ankle Surgery, Department of Orthopaedics, Zurich (Switzerland); Zanetti, Marco [University of Zurich, Department of Radiology, Zurich (Switzerland)

    2010-10-15

    To evaluate the therapeutic impact of [{sup 18}F]fluoride positron-emission tomography/computed tomography ([{sup 18}F]fluoride PET/CT) imaging on patients with unclear foot pain. Twenty-eight patients were prospectively included in this study. Therapeutic management was defined by two experienced dedicated foot surgeons before and after [{sup 18}F]fluoride PET/CT imaging. Twenty-six patients underwent cross-sectional imaging [CT, magnetic resonance (MR)] prior to PET/CT. A retrospective analysis of the magnetic resonance imaging (MRI) diagnoses was performed when a therapy change occurred after PET/CT imaging. In 13/28 (46%) patients therapeutic management was changed due to PET/CT results. Management changes occurred in patients with the following diagnoses: os trigonum syndrome; sinus tarsi syndrome; os tibiale externum syndrome; osteoarthritis of several joints; non-consolidated fragments; calcaneo-navicular coalition; plantar fasciitis; insertional tendinopathy; suggestion of periostitis; neoarticulations between metatarsal bones. Os trigonum, os tibiale externum, subtalar osteoarthritis and plantar fasciitis were only seen to be active on PET/CT images but not on MR images. [{sup 18}F]fluoride PET/CT has a substantial therapeutic impact on management in patients with unclear foot pain. (orig.)

  1. The Correlation Between Pre-treatment Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Parameters and Clinical Prognostic Factors in Pediatric Hodgkin Lymphoma

    Science.gov (United States)

    Tatcı, Ebru; Uslu Biner, İnci; Emir, Suna; Tanyıldız, Hikmet Gülşah; Özmen, Özlem; Alagöz, Engin; Gökçek, Atila; Şahin, Gürses

    2017-01-01

    Objective: To compare standardized uptake values (SUV) derived from pre-treatment 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) imaging and clinical prognostic factors in pediatric patients with Hodgkin lymphoma (HL). Methods: Pre-treatment FDG PET/CT findings of 28 children with HL were evaluated in this retrospective study. Metabolic tumor volume (MTV), SUVmax normalized by weight (SUVweight), lean body mass (SUVlbm), body surface area (SUVbsa) and plasma glucose levels of tumors (SUVglucose) were calculated using pre-treatment FDG PET/CT scan images. These metabolic parameters were correlated with clinical factors [age, sex, number of lymph node groups, presence of splenic involvement, bulky mediastinal disease, Ann Arbor stage, serum white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), serum albumin and hemoglobin levels]. Results: SUVbsa, SUVlbm, SUVweight, SUVglucose and MTV were higher in patients with stage III-IV disease, bulky tumor and ≥3 lymph node groups (p0.05). SUVbsa and SUVlbm were higher in patients with anemia (p0.05). Conclusion: Metabolic parameters derived from pre-treatment FDG PET/CT may have an important role in predicting high-risk disease in patients with HL. Also, SUVbsa and SUVlbm may be better markers than SUVweight in the quantitative evaluation of FDG PET/CT scans in pediatric patients. PMID:28291005

  2. Use of (18)F-fluorodeoxyglucose positron emission tomography-computed tomography to aid in diagnosing intestinal adenocarcinoma in 2 rhesus macaques (Macaca mulatta).

    Science.gov (United States)

    Caporizzo, Debra J; Kwiatkowski, Anna E; Chen, Ming-Kai; Beck, Amanda P; Booth, Carmen J; Zeiss, Caroline; Smith, Peter C; Carlson Scholz, Jodi A; Wilson, Steven R

    2014-06-01

    Two aged female rhesus macaques (Macaca mulatta) presented with weight loss and intermittent inappetence. The signalment and constellation of clinical signs led clinicians to suspect the presence of intestinal adenocarcinoma. Because of each animal's advanced age and inconclusive radiographic findings, a noninvasive diagnostic tool was preferred over exploratory laparotomy to assist in determining a diagnosis. Consequently, 2-[(18)F]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography-CT (FDG-PET-CT) was chosen to aid in confirming a suspicion of gastrointestinal adenocarcinoma in both animals. FDG is a glucose analogue labeled with fluorine-18 and is taken up by highly metabolically active cells, as observed in many cancers. Tomography revealed an annular constriction of the small intestine with focal FDG uptake in one animal, and an FDG avid transmural mass in the ascending colon of the second animal. Necropsy later confirmed both sites to be adenocarcinomas. This report supports the use of FDG-PET-CT as an adjunct to conventional radiography in the diagnosis of intestinal adenocarcinoma in nonhuman primates.

  3. Imaging atherosclerosis with hybrid [18F]fluorodeoxyglucose positron emission tomography/computed tomography imaging: what Leonardo da Vinci could not see.

    Science.gov (United States)

    Cocker, Myra S; Mc Ardle, Brian; Spence, J David; Lum, Cheemun; Hammond, Robert R; Ongaro, Deidre C; McDonald, Matthew A; Dekemp, Robert A; Tardif, Jean-Claude; Beanlands, Rob S B

    2012-12-01

    Prodigious efforts and landmark discoveries have led toward significant advances in our understanding of atherosclerosis. Despite significant efforts, atherosclerosis continues globally to be a leading cause of mortality and reduced quality of life. With surges in the prevalence of obesity and diabetes, atherosclerosis is expected to have an even more pronounced impact upon the global burden of disease. It is imperative to develop strategies for the early detection of disease. Positron emission tomography (PET) imaging utilizing [(18)F]fluorodeoxyglucose (FDG) may provide a non-invasive means of characterizing inflammatory activity within atherosclerotic plaque, thus serving as a surrogate biomarker for detecting vulnerable plaque. The aim of this review is to explore the rationale for performing FDG imaging, provide an overview into the mechanism of action, and summarize findings from the early application of FDG PET imaging in the clinical setting to evaluate vascular disease. Alternative imaging biomarkers and approaches are briefly discussed.

  4. Positron emission tomography/computed tomography with 18F-fluorodeoxyglucose identifies tumor growth or thrombosis in the portal vein with hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Long Sun; Hua Wu; Wei-Ming Pan; Yong-Song Guan

    2007-01-01

    Patients suffering from hepatocellular carcinoma (HCC) with tumor thrombus in the portal vein generally have a poor prognosis. Portal vein tumor thrombus must be distinguished from portal vein blood thrombus, and this identification plays a very important role in management of HCC. Conventional imaging modalities have limitations in discrimination of portal vein tumor thrombus. The application of positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG) for discrimination between tumor extension and blood thrombus has been reported in few cases of HCC, while portal tumor thrombosis and portal vein clot identified by 18F-FDG PET/CT in HCC patients has not been reported so far.We present two HCC cases, one with portal vein tumor thrombus and one thrombosis who were identified with 18F-FDG PET/CT. This report illustrates the complimentary value of combining the morphological and functional imaging in achieving a correct diagnosis in such clinical situations.

  5. Diagnostic efficacy of bone scintigraphy, magnetic resonance imaging, and positron emission tomography in bone metastases of myxoid liposarcoma.

    Science.gov (United States)

    Conill, Carlos; Setoain, Xavier; Colomo, Luis; Palacín, Antonio; Combalia-Aleu, Andreu; Pomés, Jaime; Marruecos, Jordi; Vargas, Mauricio; Maurel, Joan

    2008-03-01

    Myxoid liposarcomas (MLS) have a tendency to metastasize to unusual sites. We report an unusual case of bone metastases not detected by bone scan and neither by fluorodeoxyglucose positron emission tomography (PET-FDG) and successfully identified with magnetic resonance imaging (MRI) in a patient with metachronic MLS. Histopathological examination of the primary tumor evidenced a tumor with unfavorable prognostic markers, and the biopsy of an iliac bone lesion confirmed the diagnosis of metastatic disease. On histological grounds, the tumor showed features of a more differentiated neoplasm without foci of round cells or necrosis in the latter. MRI allowed the identification of disseminated disease compared to computed tomography (CT) and PET scans. Thus, because of the heterogeneous histological features of MLS and the biological behavior of the disease, a combined approach of FDGPET-CT and MRI, may allow a more accurate staging of soft tissue sarcomas.

  6. Imaging by single photon emission computed tomography: interest in the pre surgical check up of epilepsy; L'imagerie par tomographie d'emission monophotonique: interet dans le bilan pre-chirurgical de l'epilepsie

    Energy Technology Data Exchange (ETDEWEB)

    Biraben, A. [UPRES EA 2232, Cortex Cerebral et epilepsie, 35 - Rennes (France); Bernard, A.M. [Centre Eugene-Marquis, 35 - Rennes (France)

    1999-12-01

    With the single photon emission computed tomography, it is a more reliable technique that is at someone's disposal, especially to limit spatially the evolution of epilepsy crisis before any surgery act. The determination of the precise area is necessary to make sure that the crisis come really from this area and the determination of the functionality of this area is checked to be sure that the ablation of the zone will not lead to an unacceptable functional deficit. (N.C.)

  7. Single photon emission computed tomography (SPECT of anxiety disorders before and after treatment with citalopram

    Directory of Open Access Journals (Sweden)

    Seedat Soraya

    2004-10-01

    Full Text Available Abstract Background Several studies have now examined the effects of selective serotonin reuptake inhibitor (SSRI treatment on brain function in a variety of anxiety disorders including obsessive-compulsive disorder (OCD, posttraumatic stress disorder (PTSD, and social anxiety disorder (social phobia (SAD. Regional changes in cerebral perfusion following SSRI treatment have been shown for all three disorders. The orbitofrontal cortex (OFC (OCD, caudate (OCD, medial pre-frontal/cingulate (OCD, SAD, PTSD, temporal (OCD, SAD, PTSD and, thalamic regions (OCD, SAD are some of those implicated. Some data also suggests that higher perfusion pre-treatment in the anterior cingulate (PTSD, OFC, caudate (OCD and antero-lateral temporal region (SAD predicts subsequent treatment response. This paper further examines the notion of overlap in the neurocircuitry of treatment and indeed treatment response across anxiety disorders with SSRI treatment. Methods Single photon emission computed tomography (SPECT using Tc-99 m HMPAO to assess brain perfusion was performed on subjects with OCD, PTSD, and SAD before and after 8 weeks (SAD and 12 weeks (OCD and PTSD treatment with the SSRI citalopram. Statistical parametric mapping (SPM was used to compare scans (pre- vs post-medication, and responders vs non-responders in the combined group of subjects. Results Citalopram treatment resulted in significant deactivation (p = 0.001 for the entire group in the superior (t = 4.78 and anterior (t = 4.04 cingulate, right thalamus (t = 4.66 and left hippocampus (t = 3.96. Deactivation (p = 0.001 within the left precentral (t = 4.26, right mid-frontal (t = 4.03, right inferior frontal (t = 3.99, left prefrontal (3.81 and right precuneus (t= 3.85 was more marked in treatment responders. No pattern of baseline activation distinguished responders from non-responders to subsequent pharmacotherapy. Conclusions Although each of the anxiety disorders may be mediated by different

  8. Radiolabeling human peripheral blood stem cells for positron emission tomography (PET imaging in young rhesus monkeys.

    Directory of Open Access Journals (Sweden)

    Alice F Tarantal

    Full Text Available These studies focused on a new radiolabeling technique with copper ((64Cu and zirconium ((89Zr for positron emission tomography (PET imaging using a CD45 antibody. Synthesis of (64Cu-CD45 and (89Zr-CD45 immunoconjugates was performed and the evaluation of the potential toxicity of radiolabeling human peripheral blood stem cells (hPBSC was assessed in vitro (viability, population doubling times, colony forming units. hPBSC viability was maintained as the dose of (64Cu-TETA-CD45 increased from 0 (92% to 160 µCi/mL (76%, p>0.05. Radiolabeling efficiency was not significantly increased with concentrations of (64Cu-TETA-CD45 >20 µCi/mL (p>0.50. Toxicity affecting both growth and colony formation was observed with hPBSC radiolabeled with ≥40 µCi/mL (p0.05, and a trend towards increased radiolabeling efficiency was noted as the dose of (89Zr-Df-CD45 increased, with a greater level of radiolabeling with 160 µCi/mL compared to 0-40 µCi/mL (p<0.05. A greater than 2,000 fold-increase in the level of (89Zr-Df-CD45 labeling efficiency was observed when compared to (64Cu-TETA-CD45. Similar to (64Cu-TETA-CD45, toxicity was noted when hPBSC were radiolabeled with ≥40 µCi/mL (p<0.05 (growth, colony formation. Taken together, 20 µCi/mL resulted in the highest level of radiolabeling efficiency without altering cell function. Young rhesus monkeys that had been transplanted prenatally with 25×10(6 hPBSC expressing firefly luciferase were assessed with bioluminescence imaging (BLI, then 0.3 mCi of (89Zr-Df-CD45, which showed the best radiolabeling efficiency, was injected intravenously for PET imaging. Results suggest that (89Zr-Df-CD45 was able to identify engrafted hPBSC in the same locations identified by BLI, although the background was high.

  9. Image Optimization in Single Photon Emission Computed Tomography by Hardware Modifications with Monte Carlo Simulation

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Bahreyni Toossi

    2010-06-01

    Full Text Available Introduction: In Single Photon Emission Computed Tomography (SPECT, the projection data used for image reconstruction are distorted by several factors, including attenuation and scattering of gamma rays, collimator structure, data acquisition method, organ motion, and washout of radiopharmaceuticals. All these make reconstruction of a quantitative SPECT image very difficult. Simulation of a SPECT system is a convenient method to assess the impact of these factors on the image quality. Materials and Methods: The SIMIND Monte Carlo program was employed to simulate a Siemens E.CAM SPECT system. Verification of the simulation was performed by comparing the performance parameters of the system. The verified system was used for SPECT simulations of homogenous and inhomogeneous voxelized phantoms in conjugation with hardware modifications. The resulting data were compared with those obtained from the simulated system without any modifications. Image quality was assessed by comparing the Structural SIMularity index (SSIM, contrast, and resolution of images. Results: The energy spectra acquired from both simulated and real SPECT systems demonstrated similar energy peak regions. The resulting full-widths-at-half-maximums were 13.92 keV for the simulation and 13.58 keV for experimental data, corresponding to energy resolutions of 9.95% and 9.61%, and with calculated sensitivities of 85.39 and 85.11 cps/MBq, respectively. Better performance parameters were obtained with a hardware-modified system constructed using a 0.944 cm thickness NaI(Tl crystal covered by a layer of 0.24 cm aluminum, a  slat of 4.5 cm Pyrex as a backscattering medium, and a parallel hole collimator of Pb-Sb alloy with 2.405 cm thickness. Conclusion: The modeling of a Siemens E.CAM SPECT system was performed with the SIMIND Monte Carlo code. Results obtained with the code are in good agreement with experimental results. The findings demonstrate that the proposed hardware modifications

  10. Multimodality Imaging Probe for Positron Emission Tomography and Fluorescence Imaging Studies

    Directory of Open Access Journals (Sweden)

    Suresh K. Pandey

    2014-05-01

    Full Text Available Our goal is to develop multimodality imaging agents for use in cell tracking studies by positron emission tomography (PET and optical imaging (OI. For this purpose, bovine serum albumin (BSA was complexed with biotin (histologic studies, 5(6- carboxyfluorescein, succinimidyl ester (FAM SE (OI studies, and diethylenetriamine pentaacetic acid (DTPA for chelating gallium 68 (PET studies. For synthesis of BSA-biotin-FAM-DTPA, BSA was coupled to (+-biotin N-hydroxysuccinimide ester (biotin-NHSI. BSA- biotin was treated with DTPA-anhydride and biotin-BSA-DTPA was reacted with FAM. The biotin-BSA-DTPA-FAM was reacted with gallium chloride 3 to 5 mCi eluted from the generator using 0.1 N HCl and was passed through basic resin (AG 11 A8 and 150 mCi (100 μL, pH 7–8 was incubated with 0.1 mg of FAM conjugate (100 μL at room temperature for 15 minutes to give 66Ga-BSA-biotin-DTPA-FAM. A shaved C57 black mouse was injected with FAM conjugate (50 μL at one flank and FAM-68Ga (50 μL, 30 mCi at the other. Immediately after injection, the mouse was placed in a fluorescence imaging system (Kodak In-Vivo F, Bruker Biospin Co., Woodbridge, CT and imaged (Λex: 465 nm, Λem: 535 nm, time: 8 seconds, Xenon Light Source, Kodak. The same mouse was then placed under an Inveon microPET scanner (Siemens Medical Solutions, Knoxville, TN injected (intravenously with 25 μCi of 18F and after a half-hour (to allow sufficient bone uptake was imaged for 30 minutes. Molecular weight determined using matrix-associated laser desorption ionization (MALDI for the BSA sample was 66,485 Da and for biotin-BSA was 67,116 Da, indicating two biotin moieties per BSA molecule; for biotin-BSA-DTPA was 81,584 Da, indicating an average of 30 DTPA moieties per BSA molecule; and for FAM conjugate was 82,383 Da, indicating an average of 1.7 fluorescent moieties per BSA molecule. Fluorescence imaging clearly showed localization of FAM conjugate and FAM-68Ga at respective flanks of the mouse

  11. 18F-fluorodeoxyglucose positron emission tomography, aging, and apolipoprotein E genotype in cognitively normal persons.

    Science.gov (United States)

    Knopman, David S; Jack, Clifford R; Wiste, Heather J; Lundt, Emily S; Weigand, Stephen D; Vemuri, Prashanthi; Lowe, Val J; Kantarci, Kejal; Gunter, Jeffrey L; Senjem, Matthew L; Mielke, Michelle M; Roberts, Rosebud O; Boeve, Bradley F; Petersen, Ronald C

    2014-09-01

    Our objective was to examine associations between glucose metabolism, as measured by (18)F-fluorodeoxyglucose positron emission tomography (FDG PET), and age and to evaluate the impact of carriage of an apolipoprotein E (APOE) ε4 allele on glucose metabolism and on the associations between glucose metabolism and age. We studied 806 cognitively normal (CN) and 70 amyloid-imaging-positive cognitively impaired participants (35 with mild cognitive impairment and 35 with Alzheimer's disease [AD] dementia) from the Mayo Clinic Study of Aging, Mayo Alzheimer's Disease Research Center and an ancillary study who had undergone structural MRI, FDG PET, and (11)C-Pittsburgh compound B (PiB) PET. Using partial volume corrected and uncorrected FDG PET glucose uptake ratios, we evaluated associations of regional FDG ratios with age and carriage of an APOE ε4 allele in CN participants between the ages of 30 and 95 years, and compared those findings with the cognitively impaired participants. In region-of-interest (ROI) analyses, we found modest but statistically significant declines in FDG ratio in most cortical and subcortical regions as a function of age. We also found a main effect of APOE ε4 genotype on FDG ratio, with greater uptake in ε4 noncarriers compared with carriers but only in the posterior cingulate and/or precuneus, lateral parietal, and AD-signature meta-ROI. The latter consisted of voxels from posterior cingulate and/or precuneus, lateral parietal, and inferior temporal. In age- and sex-matched CN participants the magnitude of the difference in partial volume corrected FDG ratio in the AD-signature meta-ROI for APOE ε4 carriers compared with noncarriers was about 4 times smaller than the magnitude of the difference between age- and sex-matched elderly APOE ε4 carrier CN compared with AD dementia participants. In an analysis in participants older than 70 years (31.3% of whom had elevated PiB), there was no interaction between PiB status and APOE ε4 genotype

  12. Lymphomatous involvement of gastrointestinal tract: Evaluation by positron emission tomography with 18F-fluorodeoxyglucose

    Institute of Scientific and Technical Information of China (English)

    Sith Phongkitkarun; Vithya Varavithya; Toshiki Kazama; Silvana C Faria; Martha V Mar; Donald A Podoloff; Homer A Macapinlac

    2005-01-01

    AIM: To demonstrate the 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) findings in patients with non-Hodgkin's lymphoma (NHL) involving the gastrointestinal (GI) tract and the clinical utility of modality despite of the known normal uptake of FDG in the GI tract.METHODS: Thirty-three patients with biopsy-proven gastrointestinal NHL who had undergone FDG-PET scan were included. All the patients were injected with 10-15 mCi FDG and scanned approximately 60 min later with a CTI/Siemens HR (+) PET scanner. PET scans were reviewed and the maximum standard uptake value (SUVmax) of the lesions was measured before and after the treatment,if data were available and compared with histologic diagnoses.RESULTS: Twenty-five patients had a high-grade lymphoma and eight had a low-grade lymphoma. The stomach was the most common site of the involvement (20 patients). In high-grade lymphoma, PET showed focal nodular or diffuse hypermetabolic activity. The average SUVmax±SD was 11.58±5.83. After the therapy,the patients whose biopsies showed no evidence of lymphoma had a lower uptake without focal lesions.The SUVmax±SD decreased from 11.58±5.83 to 2.21±0.78. In patients whose post-treatment biopsies showed lymphoma, the SUVmax±SD was 9.42±6.27. Low-grade follicular lymphomas of the colon and stomach showed diffuse hypermetabolic activity in the bowel wall (SUVmax 8.2 and 10.3, respectively). The SUVmax was 2.02-3.8 (mean 3.02) in the stomach lesions of patients with MALT lymphoma.CONCLUSION: 18F-FDG PET contributes to the diagnosis of high-grade gastrointestinal non-Hodgkin's lymphoma,even when there is the normal background FDG activity. Furthermore, the SUV plays a role in evaluating treatment response. Low-grade NHL demonstrates FDG uptake but at a lesser intensity than seen in high-grade NHL.

  13. Development of a prototype Open-close positron emission tomography system

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Seiichi, E-mail: s-yama@met.nagoya-u.ac.jp; Okumura, Satoshi; Komori, Masataka; Ogata, Yoshimune; Kato, Katsuhiko [Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya (Japan); Watabe, Tadashi; Ikeda, Hayato; Kanai, Yasukazu [Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine, Osaka (Japan); Toshito, Toshiyuki [Department of Proton Therapy Physics, Nagoya Proton Therapy Center, Nagoya City West Medical Center, Nagoya (Japan); Hatazawa, Jun [Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine, Osaka (Japan); Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka (Japan)

    2015-08-15

    We developed a prototype positron emission tomography (PET) system based on a new concept called Open-close PET, which has two modes: open and close-modes. In the open-mode, the detector ring is separated into two halved rings and subject is imaged with the open space and projection image is formed. In the close-mode, the detector ring is closed to be a regular circular ring, and the subject can be imaged without an open space, and so reconstructed images can be made without artifacts. The block detector of the Open-close PET system consists of two scintillator blocks that use two types of gadolinium orthosilicate (GSO) scintillators with different decay times, angled optical fiber-based image guides, and a flat panel photomultiplier tube. The GSO pixel size was 1.6 × 2.4 × 7 mm and 8 mm for fast (35 ns) and slow (60 ns) GSOs, respectively. These GSOs were arranged into an 11 × 15 matrix and optically coupled in the depth direction to form a depth-of-interaction detector. The angled optical fiber-based image guides were used to arrange the two scintillator blocks at 22.5° so that they can be arranged in a hexadecagonal shape with eight block detectors to simplify the reconstruction algorithm. The detector ring was divided into two halves to realize the open-mode and set on a mechanical stand with which the distance between the two parts can be manually changed. The spatial resolution in the close-mode was 2.4-mm FWHM, and the sensitivity was 1.7% at the center of the field-of-view. In both the close- and open-modes, we made sagittal (y-z plane) projection images between the two halved detector rings. We obtained reconstructed and projection images of {sup 18}F-NaF rat studies and proton-irradiated phantom images. These results indicate that our developed Open-close PET is useful for some applications such as proton therapy as well as other applications such as molecular imaging.

  14. Molecular Imaging Probes for Positron Emission Tomography and Optical Imaging of Sentinel Lymph Node and Tumor

    Science.gov (United States)

    Qin, Zhengtao

    Molecular imaging is visualizations and measurements of in vivo biological processes at the molecular or cellular level using specific imaging probes. As an emerging technology, biocompatible macromolecular or nanoparticle based targeted imaging probes have gained increasing popularities. Those complexes consist of a carrier, an imaging reporter, and a targeting ligand. The active targeting ability dramatically increases the specificity. And the multivalency effect may further reduce the dose while providing a decent signal. In this thesis, sentinel lymph node (SLN) mapping and cancer imaging are two research topics. The focus is to develop molecular imaging probes with high specificity and sensitivity, for Positron Emission Tomography (PET) and optical imaging. The objective of this thesis is to explore dextran radiopharmaceuticals and porous silicon nanoparticles based molecular imaging agents. Dextran polymers are excellent carriers to deliver imaging reporters or therapeutic agents due to its well established safety profile and oligosaccharide conjugation chemistry. There is also a wide selection of dextran polymers with different lengths. On the other hand, Silicon nanoparticles represent another class of biodegradable materials for imaging and drug delivery. The success in fluorescence lifetime imaging and enhancements of the immune activation potency was briefly discussed. Chapter 1 begins with an overview on current molecular imaging techniques and imaging probes. Chapter 2 presents a near-IR dye conjugated probe, IRDye 800CW-tilmanocept. Fluorophore density was optimized to generate the maximum brightness. It was labeled with 68Ga and 99mTc and in vivo SLN mapping was successfully performed in different animals, such as mice, rabbits, dogs and pigs. With 99mTc labeled IRDye 800CW-tilmanocept, chapter 3 introduces a two-day imaging protocol with a hand-held imager. Chapter 4 proposed a method to dual radiolabel the IRDye 800CW-tilmanocept with both 68Ga and

  15. Development of a prototype Open-close positron emission tomography system

    Science.gov (United States)

    Yamamoto, Seiichi; Okumura, Satoshi; Watabe, Tadashi; Ikeda, Hayato; Kanai, Yasukazu; Toshito, Toshiyuki; Komori, Masataka; Ogata, Yoshimune; Kato, Katsuhiko; Hatazawa, Jun

    2015-08-01

    We developed a prototype positron emission tomography (PET) system based on a new concept called Open-close PET, which has two modes: open and close-modes. In the open-mode, the detector ring is separated into two halved rings and subject is imaged with the open space and projection image is formed. In the close-mode, the detector ring is closed to be a regular circular ring, and the subject can be imaged without an open space, and so reconstructed images can be made without artifacts. The block detector of the Open-close PET system consists of two scintillator blocks that use two types of gadolinium orthosilicate (GSO) scintillators with different decay times, angled optical fiber-based image guides, and a flat panel photomultiplier tube. The GSO pixel size was 1.6 × 2.4 × 7 mm and 8 mm for fast (35 ns) and slow (60 ns) GSOs, respectively. These GSOs were arranged into an 11 × 15 matrix and optically coupled in the depth direction to form a depth-of-interaction detector. The angled optical fiber-based image guides were used to arrange the two scintillator blocks at 22.5° so that they can be arranged in a hexadecagonal shape with eight block detectors to simplify the reconstruction algorithm. The detector ring was divided into two halves to realize the open-mode and set on a mechanical stand with which the distance between the two parts can be manually changed. The spatial resolution in the close-mode was 2.4-mm FWHM, and the sensitivity was 1.7% at the center of the field-of-view. In both the close- and open-modes, we made sagittal (y-z plane) projection images between the two halved detector rings. We obtained reconstructed and projection images of 18F-NaF rat studies and proton-irradiated phantom images. These results indicate that our developed Open-close PET is useful for some applications such as proton therapy as well as other applications such as molecular imaging.

  16. [11C]-(R)-PK11195 positron emission tomography in patients with complex regional pain syndrome

    Science.gov (United States)

    Jeon, So Yeon; Seo, Seongho; Lee, Jae Sung; Choi, Soo-Hee; Lee, Do-Hyeong; Jung, Ye-Ha; Song, Man-Kyu; Lee, Kyung-Jun; Kim, Yong Chul; Kwon, Hyun Woo; Im, Hyung-Jun; Lee, Dong Soo; Cheon, Gi Jeong; Kang, Do-Hyung

    2017-01-01

    Abstract Complex regional pain syndrome (CRPS) is characterized by severe and chronic pain, but the pathophysiology of this disease are not clearly understood. The primary aim of our case–control study was to explore neuroinflammation in patients with CRPS using positron emission tomography (PET), with an 18-kDa translocator protein specific radioligand [11C]-(R)-PK11195. [11C]-(R)-PK11195 PET scans were acquired for 11 patients with CRPS (30–55 years) and 12 control subjects (30–52 years). Parametric image of distribution volume ratio (DVR) for each participant was generated by applying a relative equilibrium-based graphical analysis. The DVR of [11C]-(R)-PK11195 in the caudate nucleus (t(21) = −3.209, P = 0.004), putamen (t(21) = −2.492, P = 0.022), nucleus accumbens (t(21) = −2.218, P = 0.040), and thalamus (t(21) = −2.395, P = 0.026) were significantly higher in CRPS patients than in healthy controls. Those of globus pallidus (t(21) = −2.045, P = 0.054) tended to be higher in CRPS patients than in healthy controls. In patients with CRPS, there was a positive correlation between the DVR of [11C]-(R)-PK11195 in the caudate nucleus and the pain score, the visual analog scale (r = 0.661, P = 0.026, R2 = 0.408) and affective subscales of McGill Pain Questionnaire (r = 0.604, P = 0.049, R2 = 0.364). We demonstrated that neuroinflammation of CRPS patients in basal ganglia. Our results suggest that microglial pathology can be an important pathophysiology of CRPS. Association between the level of caudate nucleus and pain severity indicated that neuroinflammation in this region might play a key role. These results may be essential for developing effective medical treatments. PMID:28072713

  17. Hyperventilation-induced reduction in cerebral blood flow: Assessment by positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Bednarczyk, E.M.; Rutherford, W.F.; Leisure, G.P.; Munger, M.A.; Panacek, E.A.; Miraldi, F.D.; Green, J.A. (Case Western Reserve Univ. School of Medicine, Cleveland, OH (USA))

    1990-05-01

    The use of positron emission tomography (PET) has been well documented as a relatively noninvasive method of measuring cerebral blood flow (CBF), both globally and regionally. The utility of readily detecting alterations in CBF is apparent, particularly when applied to the evaluation of therapeutic interventions thought to influence CBF. We report the effects of hypocapnia, an experimental condition of known cerebral vasoconstriction, in ten normal volunteers. Subjects had brain blood flow evaluated utilizing H215O as the positron emitter before and after approximately five minutes of hyperventilation. Baseline CBF was measured as a mean +/- SD of 61.2 +/- 16.3 mL/min/100 g of tissue. Mean baseline arterial blood gas values were PaO2 107.4 +/- 14 mm Hg, PaCO2 37.7 +/- 0.89 mm Hg, and pH 7.39 (calculated from mean (H+)). Post hyperventilation, global CBF was measured as 31.1 +/- 10.8 mL/min/100 g. Mean arterial blood gas values were PaO2 141.7 +/- 21 mm Hg, PaCO2 19.7 +/- 5 mm Hg, and pH 7.63 (calculated from mean (H+)). CBF decreased by a mean of 49.5 +/- 11 percent. Data analysis using the Student's t-test showed a significant change over baseline in PaCO2 (p less than 0.001) and CBF (p less than 0.001), in the hyperventilated state. Correlations were noted between the decrease in CBF and change in PaCO2 (r = 0.81) as well as between hyperventilation PaCO2 and the change in CBF (r = 0.97). We conclude that, as measured by PET, CBF decreases significantly during a state of artificial hyperventilation to a degree consistent with results seen using other methods. PET appears to be a valuable tool in the assessment of interventions that could influence CBF.

  18. Evaluating image denoising methods in myocardial perfusion single photon emission computed tomography (SPECT) imaging

    Science.gov (United States)

    Skiadopoulos, S.; Karatrantou, A.; Korfiatis, P.; Costaridou, L.; Vassilakos, P.; Apostolopoulos, D.; Panayiotakis, G.

    2009-10-01

    The statistical nature of single photon emission computed tomography (SPECT) imaging, due to the Poisson noise effect, results in the degradation of image quality, especially in the case of lesions of low signal-to-noise ratio (SNR). A variety of well-established single-scale denoising methods applied on projection raw images have been incorporated in SPECT imaging applications, while multi-scale denoising methods with promising performance have been proposed. In this paper, a comparative evaluation study is performed between a multi-scale platelet denoising method and the well-established Butterworth filter applied as a pre- and post-processing step on images reconstructed without and/or with attenuation correction. Quantitative evaluation was carried out employing (i) a cardiac phantom containing two different size cold defects, utilized in two experiments conducted to simulate conditions without and with photon attenuation from myocardial surrounding tissue and (ii) a pilot-verified clinical dataset of 15 patients with ischemic defects. Image noise, defect contrast, SNR and defect contrast-to-noise ratio (CNR) metrics were computed for both phantom and patient defects. In addition, an observer preference study was carried out for the clinical dataset, based on rankings from two nuclear medicine clinicians. Without photon attenuation conditions, denoising by platelet and Butterworth post-processing methods outperformed Butterworth pre-processing for large size defects, while for small size defects, as well as with photon attenuation conditions, all methods have demonstrated similar denoising performance. Under both attenuation conditions, the platelet method showed improved performance with respect to defect contrast, SNR and defect CNR in the case of images reconstructed without attenuation correction, however not statistically significant (p > 0.05). Quantitative as well as preference results obtained from clinical data showed similar performance of the

  19. Quality of myocardial perfusion single-photon emission tomography imaging: multicentre evaluation with a cardiac phantom.

    Science.gov (United States)

    Heikkinen, J; Ahonen, A; Kuikka, J T; Rautio, P

    1999-10-01

    The aim of the study was to evaluate quality of myocardial perfusion single-photon emission tomography (SPET) imaging in Finnish hospitals. Nineteen nuclear medicine departments participated in the study. A myocardial phantom simulating clinical stress and rest conditions was filled with routinely used isotope solution (technetium-99m or thallium-201). The cardiac insert included three reversible defects (simulating ischaemia): 30x30x14 mm(3) septal (90% recovery at rest), 30x20x14 mm(3) posterobasal (full recovery) and 20x20x14 mm(3) lateral (full recovery). There were two fixed defects (simulating infarct): 30x20x14 mm(3) postero-apical and 10x10x6 mm(3) apical. The phantom was imaged and interpreted as a myocardial perfusion patient. Reconstruction, printout and reporting were performed according to the clinical routine of each centre. Three nuclear medicine specialists anonymously evaluated the quality of the image sets. The visual scores of the experts were ranked from 1 to 5. Additionally, points from 0 to 8 were given to research reports according to how well perfusion defects were detected. Quantitative points were calculated by comparing background-subtracted and -normalized counts from 12 regions of interest between stress and rest images. Results for technetium studies (12 departments) were better than those for thallium (7 departments). The average visual scores of the experts were 3.7+/-0. 9 for all image sets, 3.2+/-0.5 for thallium users and 3.9+/-0.6 for technetium users (P=0.003). Five laboratories received a low score which, according to the specialists, is barely sufficient for limited clinical use. Average points for the reports were 5.6+/-2.1, 4.9+/-1.5 and 6.5+/-1.7 (P=0.051), and for the quantitation 8.2+/-1. 0, 7.9+/-0.4 and 8.4+/-1.1 (P=0.185), respectively. Seven out of 22 interpreters did not detect the lateral 20x20x14 mm(3) defect; five of them used thallium. This study demonstrated the heterogeneity of myocardial perfusion SPET in

  20. Quality of myocardial perfusion single-photon emission tomography imaging: multicentre evaluation with a cardiac phantom

    Energy Technology Data Exchange (ETDEWEB)

    Heikkinen, J. [Dept. of Nuclear Medicine, Etela-Savo Hospital District, Mikkeli Central Hospital, Mikkeli (Finland); Ahonen, A. [Dept. of Nuclear Medicine, Oulu University Hospital (Finland); Kuikka, J.T. [Dept. of Clinical Physiology, Kuopio University Hospital and Niuvanniemi Hospital, Kuopio (Finland); Rautio, P. [Dept. of Clinical Physiology, North Karelia Central Hospital, Joensuu (Finland)

    1999-10-01

    The aim of the study was to evaluate quality of myocardial perfusion single-photon emission tomography (SPET) imaging in Finnish hospitals. Nineteen nuclear medicine departments participated in the study. A myocardial phantom simulating clinical stress and rest conditions was filled with routinely used isotope solution (technetium-99m or thallium-201). The cardiac insert included three reversible defects (simulating ischaemia): 30 x 30 x 14 mm{sup 3} septal (90% recovery at rest), 30 x 20 x 14 mm{sup 3} posterobasal (full recovery) and 20 x 20 x 14 mm{sup 3} lateral (full recovery). There were two fixed defects (simulating infarct): 30 x 20 x 14 mm{sup 3} postero-apical and 10 x 10 x 6 mm{sup 3} apical. The phantom was imaged and interpreted as a myocardial perfusion patient. Reconstruction, printout and reporting were performed according to the clinical routine of each centre. Three nuclear medicine specialists anonymously evaluated the quality of the image sets. The visual scores of the experts were ranked from 1 to 5. Additionally, points from 0 to 8 were given to research reports according to how well perfusion defects were detected. Quantitative points were calculated by comparing background-subtracted and -normalized counts from 12 regions of interest between stress and rest images. Results for technetium studies (12 departments) were better than those for thallium (7 departments). The average visual scores of the experts were 3.7{+-}0.9 for all image sets, 3.2{+-}0.5 for thallium users and 3.9{+-}0.6 for technetium users (P=0.003). Five laboratories received a low score which, according to the specialists, is barely sufficient for limited clinical use. Average points for the reports were 5.6{+-}2.1, 4.9{+-}1.5 and 6.5{+-}1.7 (P=0.051), and for the quantitation 8.2{+-}1.0, 7.9{+-}0.4 and 8.4{+-}1.1 (P=0.185), respectively. Seven out of 22 interpreters did not detect the lateral 20 x 20 x 14 mm{sup 3} defect; five of them used thallium. This study demonstrated

  1. Characterization of positron emission tomography hypoxia tracer uptake and tissue oxygenation via electrochemical modeling

    Energy Technology Data Exchange (ETDEWEB)

    Bowen, Stephen R., E-mail: srbowen@wisc.edu [University of Wisconsin School of Medicine and Public Health, Department of Medical Physics, Madison, WI 53706 (United States); Kogel, Albert J. van der [University Medical Centre St. Radboud, Nijmegen (Netherlands); Nordsmark, Marianne [Aarhus University Hospital, Department of Experimental Clinical Oncology, Aarhus (Denmark); Bentzen, Soren M. [University of Wisconsin School of Medicine and Public Health, Department of Medical Physics, Madison, WI 53706 (United States); University of Wisconsin School of Medicine and Public Health, Department of Human Oncology, Clinical Sciences Center, Madison, WI 53792 (United States); Jeraj, Robert [University of Wisconsin School of Medicine and Public Health, Department of Medical Physics, Madison, WI 53706 (United States); University of Wisconsin School of Medicine and Public Health, Department of Human Oncology, Clinical Sciences Center, Madison, WI 53792 (United States); Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)

    2011-08-15

    Purpose: Unique uptake and retention mechanisms of positron emission tomography (PET) hypoxia tracers make in vivo comparison between them challenging. Differences in imaged uptake of two common hypoxia radiotracers, [{sup 61}Cu]Cu-ATSM and [{sup 18}F]FMISO, were characterized via computational modeling to address these challenges. Materials and Methods: An electrochemical formalism describing bioreductive retention mechanisms of these tracers under steady-state conditions was adopted to relate time-averaged activity concentration to tissue partial oxygen tension (PO{sub 2}), a common metric of hypoxia. Chemical equilibrium constants of product concentration to reactant concentration ratios were determined from free energy changes and reduction potentials of pertinent reactions reported in the literature. Resulting transformation functions between tracer uptake and PO{sub 2} were compared against measured values in preclinical models. Additionally, calculated PO{sub 2} distributions from imaged Cu-ATSM tracer activity concentrations of 12 head and neck squamous cell carcinoma (HNSCC) patients were validated against microelectrode PO{sub 2} measurements in 69 HNSCC patients. Results: Both Cu-ASTM- and FMISO-modeled PO{sub 2} transformation functions were in agreement with preclinical measured values within single-deviation confidence intervals. High correlation (r{sup 2}=0.94, P<.05) was achieved between modeled PO{sub 2} distributions and measured distributions in the patient populations. On average, microelectrode hypoxia thresholds (2.5 and 5.0 mmHg) corresponded to higher Cu-ATSM uptake [2.5 and 2.0 standardized uptake value (SUV)] and lower FMISO uptake (2.0 and 1.4 SUV). Uncertainties in the models were dominated by variations in the estimated specific activity and intracellular acidity. Conclusions: Results indicated that the high dynamic range of Cu-ATSM uptake was representative of a narrow range of low oxygen tension whose values were dependent on

  2. Study of the silicon photomultipliers and their applications in positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Chen

    2014-05-15

    This thesis deals with silicon photomultipliers (SiPM) used in scintillation detectors and their applications in positron emission tomography (PET). The study of the SiPM is mainly focused on the application to the proposed EndoTOFPET-US detector, which is a multi-modality PET detector facilitating the development of new biomarkers for pancreas and prostate cancers. A Monte Carlo simulation tool is developed for the optimization of the detector's single channel design. In order to obtain a 200 ps system coincidence time resolution and maximize the detector sensitivity, the requirements for the crystal geometry, light yield and SiPM photon detection efficiency are specified based on the simulation study. In addition, the nonlinear response of the SiPM can be corrected by the simulation tool and the energy resolution of the detector is extracted. A series of measurements are established to characterize SiPMs in a fast and reliable way with high precision. The static characterization measures the value of different components in the derived electrical model of the SiPM, whereas the dynamic characterization extracts parameters that is crucial for the operation of the SiPM. Several SiPM samples are tested and their characteristics are compared. The developed setup and the precision of the measurement fulfill the requirements of the quality assurance test for the commissioning of the EndoTOFPET-US detector. The test foresees large quantities of SiPMs to be characterized. In addition, the developed measuring procedure has contributed to the study of X-ray induced surface damage of a SiPM from Hamamatsu. Characteristics of the device are measured before and after irradiating the SiPM with different X-ray doses, the results are compared and discussed. A comparative study of a digital and an analog SiPM in gamma spectroscopy with the inorganic scintillator is presented. The characteristics of a prototype digital SiPM that is developed for the EndoTOFPETUS detector is

  3. In-vivo detection of the erythropoietin receptor in tumours using positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Fuge, Felix; Doleschel, Dennis; Rix, Anne; Gremse, Felix; Lederle, Wiltrud; Kiessling, Fabian [RWTH Aachen University, Department for Experimental Molecular Imaging (ExMI), Medical Faculty, Aachen (Germany); Wessner, Axel [Roche Diagnostics GmbH, R and D RPD Protein Chemistry, Penzberg (Germany); Winz, Oliver; Mottaghy, Felix [University Clinic RWTH Aachen, Clinic for Nuclear Medicine, Aachen (Germany)

    2014-09-09

    Recombinant human erythropoietin (rhuEpo) is used clinically to treat anaemia. However, rhuEpo-treated cancer patients show decreased survival rates and erythropoietin receptor (EpoR) expression has been found in patient tumour tissue. Thus, rhuEpo application might promote EpoR{sup +} tumour progression. We therefore developed the positron emission tomography (PET)-probe {sup 68}Ga-DOTA-rhuEpo and evaluated its performance in EpoR{sup +} A549 non-small-cell lung cancer (NSCLC) xenografts. {sup 68}Ga-DOTA-rhuEpo was generated by coupling DOTA-hydrazide to carbohydrate side-chains of rhuEpo. Biodistribution was determined in tumour-bearing mice 0.5, 3, 6, and 9 h after probe injection. Competition experiments were performed by co-injecting {sup 68}Ga-DOTA-rhuEpo and rhuEpo in five-fold excess. Probe specificity was further evaluated histologically using Epo-Cy5.5 stainings. The blood half-life of {sup 68}Ga-DOTA-rhuEpo was 2.6 h and the unbound fraction was cleared by the liver and kidney. After 6 h, the highest tumour to muscle ratio was reached. The highest {sup 68}Ga-DOTA-rhuEpo accumulation was found in liver (10.06 ± 6.26%ID/ml), followed by bone marrow (1.87 ± 0.53%ID/ml), kidney (1.58 ± 0.39 %ID/ml), and tumour (0.99 ± 0.16%ID/ml). EpoR presence in these organs was histologically confirmed. Competition experiments showed significantly (p < 0.05) lower PET-signals in tumour and bone marrow at 3 and 6 h. {sup 68}Ga-DOTA-rhuEpo shows favourable pharmacokinetic properties and detects EpoR specifically. Therefore, it might become a valuable radiotracer to monitor EpoR status in tumours and support decision-making in anaemia therapy. (orig.)

  4. Central representation of phantom limb phenomenon in amputees studied with single photon emission computerized tomography.

    Science.gov (United States)

    Liaw, M Y; You, D L; Cheng, P T; Kao, P F; Wong, A M

    1998-01-01

    To explore the possible mechanisms of phantom limb discomfort after amputation, three amputees with phantom limb pain were studied. This study examined the change of regional cerebral blood flow using technetium-99m hexamethylpropyleneamine oxime-single photon emission computerized tomography, which was arranged at the time of severe phantom limb discomfort and after the discomfort subsided or was completely relieved. Nine representative transverse slices parallel to the orbitomeatal line were selected for quantification. The cortical ribbon (2-cm thickness) was equally subdivided into 12 symmetrical pairs of sector regions of interest in each slice. The irregularly shaped regions of interest were drawn manually around the right thalamus and basal ganglion and then mirrored to the left thalamus and basal ganglion. The contralateral to ipsilateral ratio of regional cerebral blood flow for each area was calculated. The intensity of phantom limb pain was evaluated on a 0 to 10 visual analog scale. In Cases 1 and 2, the contralateral to ipsilateral regional cerebral blood flow ratios of multiple areas of the frontal, temporal, or parietal lobes were increased at the time of more severe phantom limb pain, and the ratios were normalized or even decreased when the phantom limb pain subsided. In Case 3, increased contralateral to ipsilateral regional cerebral blood flow ratios were also found over the frontal, temporal, and parietal lobe. However, most of the increased regional cerebral blood flow ratios of regions of interest in the first study persisted in the follow-up study. Also, the regional cerebral blood flow ratios of greater number of regions of interest of the same gyrus and new gyrus were increased. There was no significant right-left difference of regional cerebral blood flow over bilateral thalami and basal ganglia in all three cases. The results suggested that phantom limb pain might be associated with cortical activation involving the frontal, temporal, or

  5. Positron emission tomography imaging of CD105 expression during tumor angiogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Hao [University of Wisconsin - Madison, Department of Radiology, Madison, WI (United States); Yang, Yunan [University of Wisconsin - Madison, Department of Radiology, Madison, WI (United States); Third Military Medical University, Department of Ultrasound, Xinqiao Hospital, Chongqing (China); Zhang, Yin; Engle, Jonathan W.; Barnhart, Todd E.; Nickles, Robert J. [University of Wisconsin - Madison, Department of Medical Physics, Madison, WI (United States); Leigh, Bryan R. [TRACON Pharmaceuticals, Inc., San Diego, CA (United States); Cai, Weibo [University of Wisconsin - Madison, Department of Radiology, Madison, WI (United States); University of Wisconsin - Madison, Department of Medical Physics, Madison, WI (United States); University of Wisconsin Carbone Cancer Center, Madison, WI (United States); University of Wisconsin - Madison, Departments of Radiology and Medical Physics, School of Medicine and Public Health, Madison, WI (United States)

    2011-07-15

    Overexpression of CD105 (endoglin) correlates with poor prognosis in many solid tumor types. Tumor microvessel density (MVD) assessed by CD105 staining is the current gold standard for evaluating tumor angiogenesis in the clinic. The goal of this study was to develop a positron emission tomography (PET) tracer for imaging CD105 expression. TRC105, a chimeric anti-CD105 monoclonal antibody, was conjugated to 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) and labeled with {sup 64}Cu. FACS analysis and microscopy studies were performed to compare the CD105 binding affinity of TRC105 and DOTA-TRC105. PET imaging, biodistribution, blocking, and ex vivo histology studies were performed on 4T1 murine breast tumor-bearing mice to evaluate the ability of {sup 64}Cu-DOTA-TRC105 to target tumor angiogenesis. Another chimeric antibody, cetuximab, was used as an isotype-matched control. FACS analysis of human umbilical vein endothelial cells (HUVECs) revealed no difference in CD105 binding affinity between TRC105 and DOTA-TRC105, which was further validated by fluorescence microscopy. {sup 64}Cu labeling was achieved with high yield and specific activity. Serial PET imaging revealed that the 4T1 tumor uptake of the tracer was 8.0 {+-} 0.5, 10.4 {+-} 2.8, and 9.7 {+-} 1.8%ID/g at 4, 24, and 48 h post-injection, respectively (n = 3), higher than most organs at late time points which provided excellent tumor contrast. Biodistribution data as measured by gamma counting were consistent with the PET findings. Blocking experiments, control studies with {sup 64}Cu-DOTA-cetuximab, as well as ex vivo histology all confirmed the in vivo target specificity of {sup 64}Cu-DOTA-TRC105. This is the first successful PET imaging study of CD105 expression. Fast, prominent, persistent, and CD105-specific uptake of the tracer in the 4T1 tumor was observed. Further studies are warranted and currently underway. (orig.)

  6. Development of Traceable Phantoms for Improved Image Quantification in Positron Emission Tomography

    Science.gov (United States)

    Zimmerman, Brian

    2014-03-01

    Clinical trials for new drugs increasingly rely on imaging data to monitor patient response to the therapy being studied. In the case of radiopharmaceutical applications, imaging data are also used to estimate organ and tumor doses in order to arrive at the optimal dosage for safe and effective treatment. Positron Emission Tomography (PET) is one of the most commonly used imaging modalities for these types of applications. In large, multicenter trials it is crucial to minimize as much as possible the variability that arises due to use of different types of scanners and other instrumentation so that the biological response can be more readily evaluated. This can be achieved by ensuring that all the instruments are calibrated to a common standard and that their performance is continuously monitored throughout the trial. Maintaining links to a single standard also enables the comparability of data acquired on a heterogeneous collection of instruments in different clinical settings. As the standards laboratory for the United States, the National Institute of Standards and Technology (NIST) has been developing a suite of phantoms having traceable activity content to enable scanner calibration and performance testing. The configurations range from small solid cylindrical sources having volumes from 1 mL to 23 mL to large cylinders having a total volume of 9 L. The phantoms are constructed with 68Ge as a long-lived substitute for the more clinically useful radionuclide 18F. The contained activity values are traceable to the national standard for 68Ge and are also linked to the standard for 18F through a careful series of comparisons. The techniques that have been developed are being applied to a variety of new phantom configurations using different radionuclides. Image-based additive manufacturing techniques are also being investigated to create fillable phantoms having irregular shapes which can better mimic actual organs and tumors while still maintaining traceability

  7. Transfer of learning with an application to the physics of positron emission tomography

    Science.gov (United States)

    Aryal, Bijaya

    2007-12-01

    A series of teaching activities using physical models was developed to present some portions of physics of Positron Emission Tomography (PET) and investigate students' understanding and transfer of learning in physics to a medical technology. A teaching interview protocol consistent with a qualitative research methodology was developed and administered to the students enrolled in an algebra-based introductory level physics course. 16 students participated in individual interviews and another 21 students participated in the group sessions. The major objectives of the teaching interviews were to investigate students' transfer of physics learning from their prior experiences to the provided physical models, from one model to the other and from the models to the PET problems. The study adapted phenomenological research methodology in analyzing students' use of cognitive resources and cognitive strategies during knowledge construction and reconstruction. A resource based transfer model framed under the cognitive theory of learning and consistent with contemporary views of transfer was used to describe the transfer of physics learning. Results of the study indicated both appropriate and inappropriate use of the students' prior conceptual resources in novel contexts. Scaffolding and questioning were found to be effective in activating appropriate and suppressing the inappropriate resources. The physical models used as analogies were found useful in transferring physics learning to understand image construction in PET. Positive transfer was possible when the models were introduced in an appropriate sequence. The results of the study indicate the occurrence of three types of non-scaffolded transfer---spontaneous, semi spontaneous and non-spontaneous. The research found connections between sequencing of hints and phrasing of information in activating students' different conceptual resources. A qualitative investigation based on Vygotsky's Zone of Proximal Development (ZPD

  8. The relationship between cerebrospinal fluid markers of Alzheimer pathology and positron emission tomography tau imaging.

    Science.gov (United States)

    Gordon, Brian A; Friedrichsen, Karl; Brier, Matthew; Blazey, Tyler; Su, Yi; Christensen, Jon; Aldea, Patricia; McConathy, Jonathan; Holtzman, David M; Cairns, Nigel J; Morris, John C; Fagan, Anne M; Ances, Beau M; Benzinger, Tammie L S

    2016-08-01

    The two primary molecular pathologies in Alzheimer's disease are amyloid-β plaques and tau-immunoreactive neurofibrillary tangles. Investigations into these pathologies have been restricted to cerebrospinal fluid assays, and positron emission tomography tracers that can image amyloid-β plaques. Tau tracers have recently been introduced into the field, although the utility of the tracer and its relationship to other Alzheimer biomarkers are still unknown. Here we examined tau deposition in 41 cognitively normal and 11 cognitively impaired older adults using the radioactive tau ligand (18)F-AV-1451 (previously known as T807) who also underwent a lumbar puncture to assess cerebrospinal fluid levels of total tau (t-tau), phosphorylated tau181 (p-tau181) and amyloid-β42 Voxel-wise statistical analyses examined spatial patterns of tau deposition associated with cognitive impairment. We then related the amount of tau tracer uptake to levels of cerebrospinal fluid biomarkers. All analyses controlled for age and gender and, when appropriate, the time between imaging and lumbar puncture assessments. Symptomatic individuals (Clinical Dementia Rating > 0) demonstrated markedly increased levels of tau tracer uptake. This elevation was most prominent in the temporal lobe and temporoparietal junction, but extended more broadly into parietal and frontal cortices. In the entire cohort, there were significant relationships among all cerebrospinal fluid biomarkers and tracer uptake, notably for tau-related cerebrospinal fluid markers. After controlling for levels of amyloid-β42, the correlations with tau uptake were r = 0.490 (P < 0.001) for t-tau and r = 0.492 (P < 0.001) for p-tau181 Within the cognitively normal cohort, levels of amyloid-β42, but not t-tau or p-tau181, were associated with elevated tracer binding that was confined primarily to the medial temporal lobe and adjacent neocortical regions. AV-1451 tau binding in the medial temporal, parietal, and frontal cortices

  9. Novel amphiphilic probes for [18F]-radiolabeling preformed liposomes and determination of liposomal trafficking by positron emission tomography.

    Science.gov (United States)

    Urakami, Takeo; Akai, Shuji; Katayama, Yurie; Harada, Norihiro; Tsukada, Hideo; Oku, Naoto

    2007-12-27

    Positron-emission tomography (PET) is a noninvasive real-time functional imaging system and is expected to be useful for the development of new drug candidates in clinical trials. For its application with preformulated liposomes, we devised an optimized [18F]-compound and developed a direct liposome modification method that we termed the "solid-phase transition method". We were successful in using 1-[18F]fluoro-3,6-dioxatetracosane ([18F]7a) for in vivo trafficking of liposomes. This method might be a useful tool in preclinical and clinical studies of lipidic particle-related drugs.

  10. Effect of expression of P-glycoprotein on technetium-99m methoxyisobutylisonitrile single photon emission computed tomography of brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Yasushi; Matsumura, Akira; Nose, Tadao [Tsukuba Univ., Ibaraki (Japan). Inst. of Clinical Medicine

    2002-08-01

    The expression of P-glycoprotein was investigated imunohistochemically in 26 brain tumor tissues and compared with the findings of technetium-99m methoxyisobutylisonitrile single photon emission computed tomography ({sup 99m}Tc-MIBI SPECT) to clarify the effect of P-glycoprotein on the diagnostic accuracy. P-glycoprotein labeling index of both tumor cells and vascular endothelial cells showed no clear relationship with the findings of {sup 99m}Tc-MIBI SPECT imaging. Expression of P-glycoprotein has no effect on the diagnostic accuracy of {sup 99m}Tc-MIBI SPECT. (author)

  11. Sentinel Lymph Node Detection by 3D Freehand Single-Photon Emission Computed Tomography in Early Stage Breast Cancer

    Directory of Open Access Journals (Sweden)

    Salih Sinan Gültekin

    2016-06-01

    Full Text Available We herein present our first experience obtained by 3D freehand single-photon emission computed tomography (SPECT (F-SPECT guidance for sentinel lymph node detection (SLND in two patients with early stage breast cancer. F-SPECT guidance was carried out using one-day protocol in one case and by the two-day protocol in the other one. SLND was performed successfully in both patients. Histopathologic evaluation showed that the excised nodes were tumor negative. Thus, patients underwent breast-conserving surgery alone.

  12. Possibilities of positron emission tomography in the diagnosis of primary and recurrent ovarian cancer: a review of literature

    Directory of Open Access Journals (Sweden)

    L. A. Ashrafyan

    2012-01-01

    Full Text Available Positron emission tomography (PET is a current radionuclide imaging technique that can supplement a diagnostic process with information on physiological and metabolic disorders in the foci of injury and specify the characteristics of a tumor process. The paper analyzes publications on the use of PET with 18F-fluorodeoxyglucose in different clinical situations in the presence of ovarian cancer for both the identification of early-stage disease, the differential diagnosis of ovarian masses and the timely detection of recurrences, follow-up during and after combination treatment. The authors’ opinions that the technique is restricted, which yields false-positive and false-negative results, are given.

  13. Positron emission tomography assessment of effects of benzodiazepines on regional glucose metabolic rate in patients with anxiety disorder

    Energy Technology Data Exchange (ETDEWEB)

    Buchsbaum, M.S.; Wu, J.; Haier, R.; Hazlett, E.; Ball, R.; Katz, M.; Sokolski, K.; Lagunas-Solar, M.; Langer, D.

    1987-06-22

    Patients with generalized anxiety disorder (n = 18) entered a 21-day, double-blind, placebo-controlled random assignment trial of clorazepate. Positron emission tomography with YF-deoxyglucose was carried out before and after treatment. Decreases in glucose metabolic rate in visual cortex and relative increases in the basal ganglia and thalamus were found. A correlation between regional changes in metabolic rate and regional benzodiazepine receptor binding density from other human autopsy studies was observed; brain regions highest in receptor density showed the greatest decrease in rate.

  14. Emission and transmission tomography systems to be developed for the future needs of Jules Horowitz material testing reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kotiluoto, Petri [VTT Technical Research Centre of Finland, P.O.Box 1000, FI-02044 VTT (Finland)], E-mail: petri.kotiluoto@vtt.fi; Wasastjerna, Frej; Kekki, Tommi [VTT Technical Research Centre of Finland, P.O.Box 1000, FI-02044 VTT (Finland); Sipilae, Heikki; Banzuzi, Kukka [Oxford Instruments Analytical Oy, Nihtisillankuja 5, P.O.Box 85, FI-02631 Espoo (Finland); Kinnunen, Petri; Heikinheimo, Liisa [VTT Technical Research Centre of Finland, P.O.Box 1000, FI-02044 VTT (Finland)

    2009-08-01

    The new 100 MW Jules Horowitz material testing reactor will be built in Cadarache, France. It will support, for instance, research on new types of innovative nuclear fuel. As a Finnish in-kind contribution, 3D emission and transmission tomography equipment will be delivered for both the reactor and the active component storage pool. The image reconstruction of activities inside the used nuclear fuel will be based on gamma spectrometry measurements. A new type of underwater digital X-ray linear detector array is under development for transmission imaging, based on GaAs and direct conversion of X-rays into an electrical signal. A shared collimator will be used for both emission and transmission measurements. Some preliminary design has been performed. For the current design, the expected gamma spectrometric response of a typical high-purity germanium detector has been simulated with MCNP for minimum and maximum source activities (specified by CEA) to be measured in future.

  15. A computer tomography-based spatial normalization for the analysis of [{sup 18}F]fluorodeoxyglucose position emission tomography of the brain

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hanna; Choi, Jae Yong; Ryu, Young Hoon; Lyoo, Chul Hyoung [Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Jin Su [Molecular Imaging Research Center, Korea Institute Radiological and Medical Science, Seoul(Korea, Republic of)

    2014-12-15

    We developed a new computed tomography (CT)-based spatial normalization method and CT template to demonstrate its usefulness in spatial normalization of positron emission tomography (PET) images with [{sup 18}F] fluorodeoxyglucose (FDG) PET studies in healthy controls. Seventy healthy controls underwent brain CT scan (120 KeV, 180 mAs, and 3 mm of thickness) and [{sup 18}F] FDG PET scans using a PET/CT scanner. T1-weighted magnetic resonance (MR) images were acquired for all subjects. By averaging skull-stripped and spatially-normalized MR and CT images, we created skull-stripped MR and CT templates for spatial normalization. The skull-stripped MR and CT images were spatially normalized to each structural template. PET images were spatially normalized by applying spatial transformation parameters to normalize skull-stripped MR and CT images. A conventional perfusion PET template was used for PET-based spatial normalization. Regional standardized uptake values (SUV) measured by overlaying the template volume of interest (VOI) were compared to those measured with FreeSurfer-generated VOI (FSVOI). All three spatial normalization methods underestimated regional SUV values by 0.3-20% compared to those measured with FSVOI. The CT-based method showed slightly greater underestimation bias. Regional SUV values derived from all three spatial normalization methods were correlated significantly (p < 0.0001) with those measured with FSVOI. CT-based spatial normalization may be an alternative method for structure-based spatial normalization of [18F] FDG PET when MR imaging is unavailable. Therefore, it is useful for PET/CT studies with various radiotracers whose uptake is expected to be limited to specific brain regions or highly variable within study population.

  16. The value of F-18 fluorodeoxyglucose positron emission tomography/computed tomography in asymptomatic examinees with unexplained elevated blood carcinoembryonic antigen levels

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wenfeng [The First Affiliated Hospital of Wenzhou Medical University, Laboratory for Advanced Interdisciplinary Research, Institutes of Translational Medicine, Wenzhou (China); The First Affiliated Hospital of Wenzhou Medical University, Department of Radiation Oncology, Wenzhou (China); Yin, Weiwei [The First Affiliated Hospital of Wenzhou Medical University, Division of PET/CT, Department of Radiology, Wenzhou (China); Ou, Rongying [The First Affiliated Hospital of Wenzhou Medical University, Laboratory for Advanced Interdisciplinary Research, Institutes of Translational Medicine, Wenzhou (China); The First Affiliated Hospital of Wenzhou Medical University, Department of Gynaecology and Obstetrics, Wenzhou (China); Chen, Ting; Xiong, Lingling; Xu, Yunsheng [The First Affiliated Hospital of Wenzhou Medical University, Laboratory for Advanced Interdisciplinary Research, Institutes of Translational Medicine, Wenzhou (China); The First Affiliated Hospital of Wenzhou Medical University, Department of Dermatovenereology, Wenzhou (China); Cheng, Dezhi; Xie, Deyao [The First Affiliated Hospital of Wenzhou Medical University, Laboratory for Advanced Interdisciplinary Research, Institutes of Translational Medicine, Wenzhou (China); The First Affiliated Hospital of Wenzhou Medical University, Department of Cardiothoracic Surgery, Wenzhou (China); Zheng, Xiangwu; Zhao, Liang [The First Affiliated Hospital of Wenzhou Medical University, Laboratory for Advanced Interdisciplinary Research, Institutes of Translational Medicine, Wenzhou (China); The First Affiliated Hospital of Wenzhou Medical University, Division of PET/CT, Department of Radiology, Wenzhou (China); The First Affiliated Hospital of Wenzhou Medical University, Institutes of Intelligent and Molecular Imaging, Wenzhou (China)

    2016-04-15

    Cancer is still a clinical challenge, with many efforts invested in order to achieve timely detection. Unexplained elevated blood carcinoembryonic antigen levels are occasionally observed in an asymptomatic population and considered as a risk factor of cancers. The purpose of this study was to determine the validity of 18 F-fluorodeoxyglucose-positron emission tomography/computed tomography (F-18 FDG-PET/CT) for detecting cancer in an asymptomatic population with an unexplained elevation in blood carcinoembryonic antigen (CEA) levels. This retrospective study included a total of 1920 asymptomatic examinees conducted from August 2011 through September 2013. The participants underwent CEA assay and conventional medical imaging (CEA-conventional), or CEA assay and F-18 FDG-PET/CT (CEA-PET/CT). The validity of conventional medical imaging and CEA-PET/CT scanning for detecting cancer and early-stage cancer in an asymptomatic population with an unexplained elevation in blood CEA levels were evaluated. Sensitivity, specificity, cancer detection rate, missed cancer detection rate, early-stage cancer detection rate, and early-stage cancer ratio using the CEA-PET/CT scanning were 96.6 %, 100 %, 10.4 %, 0.4 %, 3.7 %, and 34.5 %, respectively. In contrast, the corresponding values obtained using the conventional medical imaging were 50.6 % (P < 0.0001), 100 % (P > 0.9999), 50.6 % (P < 0.0001), 99.9 % (P = 0.055), 2.6 % (P < 0.0001), 2.5 % (P = 0.04), 0.7 % (P = 0.0004), and 14.5 % (P = 0.002), respectively. The F-18 FDG-PET/CT scanning significantly improved the validity of the cancer detection program in the asymptomatic population with an unexplained elevation in CEA levels. (orig.)

  17. Impact of Pretreatment Combined {sup 18}F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Staging on Radiation Therapy Treatment Decisions in Locally Advanced Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Sweet Ping, E-mail: sweet.ng@petermac.org [Peter MacCallum Cancer Centre, Melbourne (Australia); David, Steven [Peter MacCallum Cancer Centre, Melbourne (Australia); Alamgeer, Muhammad; Ganju, Vinod [Monash Cancer Centre, Melbourne (Australia)

    2015-09-01

    Purpose: To assess the diagnostic performance of pretreatment {sup 18}F-fluorodeoxyglucose positron emission tomography/computed tomography ({sup 18}F-FDG PET/CT) and its impact on radiation therapy treatment decisions in patients with locally advanced breast cancer (LABC). Methods and Materials: Patients with LABC with Eastern Cooperative Oncology Group performance status <2 and no contraindication to neoadjuvant chemotherapy, surgery, and adjuvant radiation therapy were enrolled on a prospective trial. All patients had pretreatment conventional imaging (CI) performed, including bilateral breast mammography and ultrasound, bone scan, and CT chest, abdomen, and pelvis scans performed. Informed consent was obtained before enrolment. Pretreatment whole-body {sup 18}F-FDG PET/CT scans were performed on all patients, and results were compared with CI findings. Results: A total of 154 patients with LABC with no clinical or radiologic evidence of distant metastases on CI were enrolled. Median age was 49 years (range, 26-70 years). Imaging with PET/CT detected distant metastatic disease and/or locoregional disease not visualized on CI in 32 patients (20.8%). Distant metastatic disease was detected in 17 patients (11.0%): 6 had bony metastases, 5 had intrathoracic metastases (pulmonary/mediastinal), 2 had distant nodal metastases, 2 had liver metastases, 1 had pulmonary and bony metastases, and 1 had mediastinal and distant nodal metastases. Of the remaining 139 patients, nodal disease outside conventional radiation therapy fields was detected on PET/CT in 15 patients (10.8%), with involvement of ipsilateral internal mammary nodes in 13 and ipsilateral level 5 cervical nodes in 2. Conclusions: Imaging with PET/CT provides superior diagnostic and staging information in patients with LABC compared with CI, which has significant therapeutic implications with respect to radiation therapy management. Imaging with PET/CT should be considered in all patients undergoing primary

  18. Can positron emission tomography/computed tomography with the dual tracers fluorine-18 fluoroestradiol and fluorodeoxyglucose predict neoadjuvant chemotherapy response of breast cancer?--A pilot study.

    Directory of Open Access Journals (Sweden)

    Zhongyi Yang

    Full Text Available OBJECTIVE: To assess the clinical value of dual tracers Positron emission tomography/computed tomography (PET/CT (18F-fluoroestradiol ((18F-FES and (18F-fluorodeoxyglucose ((18F-FDG in predicting neoadjuvant chemotherapy response (NAC of breast cancer. METHODS: Eighteen consecutive patients with newly diagnosed, non-inflammatory, stage II and III breast cancer undergoing NAC were included. Before chemotherapy, they underwent both (18F-FES and (18F-FDG PET/CT scans. Surgery was performed after three to six cycles of chemotherapy. Tumor response was graded and divided into two groups: the responders and non-responders. We used the maximum standardized uptake value (SUVmax to qualify each primary lesion. RESULTS: Pathologic analysis revealed 10 patients were responders while the other 8 patients were non-responders. There was no statistical difference of SUVmax-FDG and tumor size between these two groups (P>0.05. On the contrary, SUVmax-FES was lower in responders (1.75±0.66 versus 4.42±1.14; U=5, P=0.002; and SUVmax-FES/FDG also showed great value in predicting outcome (0.16±0.06 versus 0.54±0.22; U=5, P=0.002. CONCLUSIONS: Our study showed (18F-FES PET/CT might be feasible to predict response of NAC. However, whether the use of dual tracers (18F-FES and (18F-FDG has complementary value should be further studied.

  19. Differentiation of myocardial ischemia and infarction assessed by dynamic computed tomography perfusion imaging and comparison with cardiac magnetic resonance and single-photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Tanabe, Yuki; Kido, Teruhito; Kurata, Akira; Miyagawa, Masao; Mochizuki, Teruhito [Ehime University Graduate School of Medicine, Department of Radiology, Toon, Ehime (Japan); Uetani, Teruyoshi; Kono, Tamami; Ogimoto, Akiyoshi [Ehime University Graduate School of Medicine, Department of Cardiology, Pulmonology, Hypertension and Nephrology, Toon, Ehime (Japan); Soma, Tsutomu [FUJIFILM RI Pharma Co., Ltd., QMS Group, Quality Assurance Department, Tokyo (Japan); Graduate School of Medicine, University of Tokyo, Department of Radiology, Tokyo (Japan); Murase, Kenya [Osaka University Graduate School of Medicine, Department of Medical Physics and Engineering, Division of Medical Technology and Science, Faculty of Health Science, Osaka (Japan); Iwaki, Hirotaka [Ehime University Graduate School of Medicine, Center for Clinical Research Data and Biostatistics, Toon, Ehime (Japan)

    2016-11-15

    To evaluate the feasibility of myocardial blood flow (MBF) by computed tomography from dynamic CT perfusion (CTP) for detecting myocardial ischemia and infarction assessed by cardiac magnetic resonance (CMR) or single-photon emission computed tomography (SPECT). Fifty-three patients who underwent stress dynamic CTP and either SPECT (n = 25) or CMR (n = 28) were retrospectively selected. Normal and abnormal perfused myocardium (ischemia/infarction) were assessed by SPECT/CMR using 16-segment model. Sensitivity and specificity of CT-MBF (mL/g/min) for detecting the ischemic/infarction and severe infarction were assessed. The abnormal perfused myocardium and severe infarction were seen in SPECT (n = 90 and n = 19 of 400 segments) and CMR (n = 223 and n = 36 of 448 segments). For detecting the abnormal perfused myocardium, sensitivity and specificity were 80 % (95 %CI, 71-90) and 86 % (95 %CI, 76-91) in SPECT (cut-off MBF, 1.23), and 82 % (95 %CI, 76-88) and 87 % (95 %CI, 80-92) in CMR (cut-off MBF, 1.25). For detecting severe infarction, sensitivity and specificity were 95 % (95 %CI, 52-100) and 72 % (95 %CI, 53-91) in SPECT (cut-off MBF, 0.92), and 78 % (95 %CI, 67-97) and 80 % (95 %CI, 58-86) in CMR (cut-off MBF, 0.98), respectively. Dynamic CTP has a potential to detect abnormal perfused myocardium and severe infarction assessed by SPECT/CMR using comparable cut-off MBF. (orig.)

  20. Correlation of uptake patterns on single-photon emission computed tomography/computed tomography (SPECT/CT)and treatment response in patients with knee pain

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Geon; Hwang, Kyung Hoon; Lee, Hae Jin; Kim, Seog Gyun; Lee, Beom Koo [Gachon University Gil Hospital, Incheon (Korea, Republic of)

    2016-06-15

    To determine whether treatment response in patients with knee pain could be predicted using uptake patterns on single-photon emission computed tomography/computed tomography (SPECT/CT) images. Ninety-five patients with knee pain who had undergone SPECT/CT were included in this retrospective study. Subjects were divided into three groups: increased focal uptake (FTU), increased irregular tracer uptake (ITU), and no tracer uptake (NTU). A numeric rating scale (NRS-11) assessed pain intensity. We analyzed the association between uptake patterns and treatment response using Pearson's chi-square test and Fisher's exact test. Uptake was quantified from SPECT/CT with region of interest (ROI) counting, and an intraclass correlation coefficient (ICC) calculated agreement. We used Student' t-test to calculate statistically significant differences of counts between groups and the Pearson correlation to measure the relationship between counts and initial NRS-1k1. Multivariate logistic regression analysis determined which variables were significantly associated with uptake. The FTU group included 32 patients; ITU, 39; and NTU, 24. With conservative management, 64 % of patients with increased tracer uptake (TU, both focal and irregular) and 36 % with NTU showed positive response. Conservative treatment response of FTU was better than NTU, but did not differ from that of ITU. Conservative treatment response of TU was significantly different from that of NTU (OR 3.1; p 0.036). Moderate positive correlation was observed between ITU and initial NRS-11. Age and initial NRS-11 significantly predicted uptake. Patients with uptake in their knee(s) on SPECT/CT showed positive treatment response under conservative treatment.

  1. [{sup 11}C]Choline positron emission tomography/computed tomography for staging and restaging of patients with advanced prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tuncel, Murat; Souvatzoglou, Michael; Herrmann, Ken [Department of Nuclear Medicine, Klinikum rechts der lsar, Technische Universitaet Muenchen, 81675 Munich (Germany); Stollfuss, Jens [Department of Radiology, Technische Universitaet Muenchen, 81675 Munich (Germany); Schuster, Tibor [Department of Statistics, Technische Universitaet Muenchen, 81675 Munich (Germany); Weirich, Gregor [Department of Pathology, Technische Universitaet Muenchen, 81675 Munich (Germany); Wester, Hans-Juergen; Schwaiger, Markus [Department of Nuclear Medicine, Klinikum rechts der lsar, Technische Universitaet Muenchen, 81675 Munich (Germany); Krause, Bernd J. [Department of Nuclear Medicine, Klinikum rechts der lsar, Technische Universitaet Muenchen, 81675 Munich (Germany)], E-mail: bernd-joachim.krause@tum.de

    2008-08-15

    Introduction: To evaluate [{sup 11}C]Choline positron emission tomography (PET)/computed tomography (CT) for staging and restaging of patients with advanced prostate cancer and to compare the diagnostic performance of PET, CT and PET/CT. Methods: Forty-five consecutive patients with advanced prostate cancer underwent [{sup 11}C]Choline-PET/CT between 5/2004 and 2/2006. Results: Overall, 295 lesions were detected: PET alone, 178 lesions; diagnostic CT, 221 lesions; PET/CT (low-dose CT), 272 lesions; PET/CT (diagnostic CT), 295 lesions. Two thirds of the lesions were located in the bone; one third in the prostate, lymph nodes, periprostatic tissue and soft tissue (lung, liver). The use of diagnostic CT did not result in a statistically significant difference with respect to lesion localization certainty and lesion characterization (P=.063, P=.063). PET-negative but PET/CT-positive lesions were mostly localized in the bone (78%, 91/117) as were PET-positive and CT-negative lesions (72%, 53/74). Of the latter, 91% (48/53) represented bone marrow and 9% (5/53) cortical involvement. Conclusions: Staging and restaging with [{sup 11}C]Choline PET/CT in patients with advanced prostate cancer improve the assessment of local and regional recurrent as well as metastatic disease including skeletal manifestations. [{sup 11}C]Choline PET/CT (with a low-dose CT) results in improved localization and lesion characterization. [{sup 11}C]Choline PET/CT provides an added value for skeletal manifestations. [{sup 11}C]Choline PET/CT changed disease management in 11 (24%) of 45 patients with advanced prostate cancer.

  2. Combination of 18F-fluorodeoxyglucose positron emission tomography/computed tomography and magnetic resonance imaging is an optimal way to evaluate rheumatoid arthritis in rats dynamically

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei-tao; DU Xiang-ke; HUO Tian-long; WEI Zheng-mao; HAO Chuan-xi; AN Bei

    2013-01-01

    Background Rheumatoid arthritis (RA) is a chronic,systemic autoimmune inflammatory disorder.Many methods have been used to observe the progress of RA.The purpose of this study was to observe the progress of RA in rats with 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT),magnetic resonance (MR) imaging and arthritis score,and analyze the relationships among different methods in evaluation of RA.Methods Sixteen healthy Sprague Dawley (SD) rats about 8-week old were randomly assigned to a RA group and a control group.Bovine type Ⅱ emulsified incomplete Freud's adjuvant was used to induce arthritis in the RA group.Arthritis score of the rats in two groups were recorded,and 18F-FDG PET/CT,MR imaging were performed both on the corresponding rats every 3 days.All the rats were sacrificed at week 5,and histopathological examination was performed on rat knees stained with haematoxylin and eosin.Results The arthritis score and the standard uptake value (SUV) of knee joints in RA rats increased with the progression of arthritis gradually.Both peaks of arthritis score and SUV appeared at 21 days after the first immune injection,then the arthritis score and SUV of knee joints decreased slowly.The arthritis scores of knee joints in RA rats were positively correlated with their SUV changes.The MR images were confirmed by the histopathological studies.Conclusion PET/CT can detect the earliest molecular metabolism changes of RA,and MR imaging can follow up the dynamical anatomical changes of RA,all of which indicated that PET/CT and MR imaging may be applied as useful tools to monitor the progress of RA.

  3. Clinical value of {sup 18}F-fluorodihydroxyphenylalanine positron emission tomography/computed tomography ({sup 18}F-DOPA PET/CT) for detecting pheochromocytoma

    Energy Technology Data Exchange (ETDEWEB)

    Luster, Markus; Zeich, Katrin; Glatting, Gerhard; Buck, Andreas K.; Solbach, Christoph; Reske, Sven N. [University of Ulm, Department of Nuclear Medicine, Ulm (Germany); Karges, Wolfram [RWTH Aachen, Division of Endocrinology and Diabetes, Aachen (Germany); Pauls, Sandra [University of Ulm, Department of Radiology, Ulm (Germany); Verburg, Frederik A. [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); Dralle, Henning [University Halle-Wittenberg, Department of General, Visceral and Vascular Surgery, Halle (Germany); Neumaier, Bernd [University of Ulm, Department of Nuclear Medicine, Ulm (Germany); Max-Planck-Institut fuer Neurologische Forschung, Section for Radiochemistry, Cologne (Germany); Mottaghy, Felix M. [University of Ulm, Department of Nuclear Medicine, Ulm (Germany); RWTH Aachen, Department of Nuclear Medicine, Aachen (Germany)

    2010-03-15

    In detecting pheochromocytoma (PHEO), positron emission tomography (PET) with the radiolabelled amine precursor {sup 18}F-fluorodihydroxyphenylalanine ({sup 18}F-DOPA) offers excellent specificity, while computed tomography (CT) provides high sensitivity and ability to localize lesions; therefore, the combination of these modalities could be advantageous in this setting. The aim of this study was to investigate whether combined {sup 18}F-DOPA PET/CT more accurately detects and localizes PHEO lesions than does each modality alone. {sup 18}F-DOPA PET, CT and {sup 18}F-DOPA PET/CT images of 25 consecutive patients undergoing diagnostic scanning of suspected sporadic or multiple endocrine neoplasia type 2 syndrome-associated PHEO were reviewed retrospectively in randomized sequence. Two blinded observers scored the images regarding the likelihood of PHEO being present and localizable. Results were correlated with subsequent clinical history and, when available, histology. Of the 19 lesions detected by all three modalities, PET identified each as positive for PHEO, but was unable to definitively localize 15 of 19 (79%). CT could definitively localize all 19 lesions, but could not definitively diagnose or exclude PHEO in 18 of 19 (95%) lesions. Furthermore, CT falsely identified as negative for PHEO one lesion which was judged to be positive for this tumor by both PET and PET/CT. Only in PET/CT scans were all 19 lesions accurately characterized and localized. On a per-patient basis, the sensitivity of {sup 18}F-DOPA PET/CT for PHEO was 100% and the specificity 88%, with a 100% positive predictive value and an 88% negative predictive value. {sup 18}F-DOPA PET/CT more accurately diagnoses and localizes adrenal and extra-adrenal masses suspicious for PHEO than do {sup 18}F-DOPA PET or CT alone. (orig.)

  4. Positron Emission Tomography/Computed Tomography Imaging of Residual Skull Base Chordoma Before Radiotherapy Using Fluoromisonidazole and Fluorodeoxyglucose: Potential Consequences for Dose Painting

    Energy Technology Data Exchange (ETDEWEB)

    Mammar, Hamid, E-mail: hamid.mammar@unice.fr [Radiation Oncology Department, Antoine Lacassagne Center, Nice (France); CNRS-UMR 6543, Institute of Developmental Biology and Cancer, University of Nice Sophia Antipolis, Nice (France); Kerrou, Khaldoun; Nataf, Valerie [Department of Nuclear Medicine and Radiopharmacy, Tenon Hospital, and University Pierre et Marie Curie, Paris (France); Pontvert, Dominique [Proton Therapy Center of Orsay, Curie Institute, Paris (France); Clemenceau, Stephane [Department of Neurosurgery, Pitie-Salpetriere Hospital, Paris (France); Lot, Guillaume [Department of Neurosurgery, Adolph De Rothschild Foundation, Paris (France); George, Bernard [Department of Neurosurgery, Lariboisiere Hospital, Paris (France); Polivka, Marc [Department of Pathology, Lariboisiere Hospital, Paris (France); Mokhtari, Karima [Department of Pathology, Pitie-Salpetriere Hospital, Paris (France); Ferrand, Regis; Feuvret, Loiec; Habrand, Jean-louis [Proton Therapy Center of Orsay, Curie Institute, Paris (France); Pouyssegur, Jacques; Mazure, Nathalie [CNRS-UMR 6543, Institute of Developmental Biology and Cancer, University of Nice Sophia Antipolis, Nice (France); Talbot, Jean-Noeel [Department of Nuclear Medicine and Radiopharmacy, Tenon Hospital, and University Pierre et Marie Curie, Paris (France)

    2012-11-01

    Purpose: To detect the presence of hypoxic tissue, which is known to increase the radioresistant phenotype, by its uptake of fluoromisonidazole (18F) (FMISO) using hybrid positron emission tomography/computed tomography (PET/CT) imaging, and to compare it with the glucose-avid tumor tissue imaged with fluorodeoxyglucose (18F) (FDG), in residual postsurgical skull base chordoma scheduled for radiotherapy. Patients and Methods: Seven patients with incompletely resected skull base chordomas were planned for high-dose radiotherapy (dose {>=}70 Gy). All 7 patients underwent FDG and FMISO PET/CT. Images were analyzed qualitatively by visual examination and semiquantitatively by computing the ratio of the maximal standardized uptake value (SUVmax) of the tumor and cerebellum (T/C R), with delineation of lesions on conventional imaging. Results: Of the eight lesion sites imaged with FDG PET/CT, only one was visible, whereas seven of nine lesions were visible on FMISO PET/CT. The median SUVmax in the tumor area was 2.8 g/mL (minimum 2.1; maximum 3.5) for FDG and 0.83 g/mL (minimum 0.3; maximum 1.2) for FMISO. The T/C R values ranged between 0.30 and 0.63 for FDG (median, 0.41) and between 0.75 and 2.20 for FMISO (median,1.59). FMISO T/C R >1 in six lesions suggested the presence of hypoxic tissue. There was no correlation between FMISO and FDG uptake in individual chordomas (r = 0.18, p = 0.7). Conclusion: FMISO PET/CT enables imaging of the hypoxic component in residual chordomas. In the future, it could help to better define boosted volumes for irradiation and to overcome the radioresistance of these lesions. No relationship was founded between hypoxia and glucose metabolism in these tumors after initial surgery.

  5. Highly metabolic thrombus of the portal vein: 18F fluorodeoxyglucose positron emission tomography/computer tomography demonstration and clinical significance in hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    AIM: To assess the ability of 18F-fluorodeoxyglucose positron emission tomography/computer tomography (18F-FDG PET/CT) to differentiate between benign and malignant portal vein thrombosis in hepatocellular carcinoma (HCC) patients. METHODS: Five consecutive patients who had HBV cirrhosis, biopsy-proven HCC, and thrombosis of the main portal vein and/or left/right portal vein on ultrasound (US), computer tomography (CT) or magnetic resonance imaging (MRI) were studied with 18F-FDG PET/CT. The presence or absence of a highly metabolic thrombus on 18F-FDG PET/CT was considered diagnostic for malignant or benign portal vein thrombosis, respectively. All patients were followed-up monthly with US, CT or MRI. Shrinkage of the thrombus or recanalization of the vessels on US, CT or MRI during follow-up was considered to be definitive evidence of the benign nature of the thrombosis, whereas enlargement of the thrombus, disruption of the vessel wall, and parenchymal infiltration over follow-up were considered to be consistent with malignancy 18F-FDG PET/CT, and US, CT or MRI results were compared. RESULTS: Follow-up (1 to 10 mo) showed signs of malignant thrombosis in 4 of the 5 patients. US, CT or MRI produced a true-positive result for malignancy in 4of the patients, and a false-positive result in 1.18F-FDG PET/CT showed a highly metabolic thrombus in 4 of the 5 patients.18F-FDG PET/CT achieved a true-positive result in all 4 of these patients, and a true-negative result in the other patient. No false-positive result was observed using 18F-FDG PET/CT.CONCLUSION: 18F-FDG PET/CT may be helpful in discriminating between benign and malignant portal vein thrombi. Patients may benefit from 18F-FDG PET/OT when portal vein thrombi can not be diagnosed exactly by US, CT or MRI.

  6. T cell homing to tumors detected by 3D-coordinated positron emission tomography and magnetic resonance imaging

    DEFF Research Database (Denmark)

    Agger, Ralf; Petersen, Mikkel; Petersen, Charlotte Christie;

    2007-01-01

    A general hindrance to progress in adoptive cellular therapy is the lack of detailed knowledge of the fate of transferred cells in the body of the recipient. In this study, we present a novel technique for tracking of 124I-labeled cells in situ, which combines the high spatial resolution of magne......A general hindrance to progress in adoptive cellular therapy is the lack of detailed knowledge of the fate of transferred cells in the body of the recipient. In this study, we present a novel technique for tracking of 124I-labeled cells in situ, which combines the high spatial resolution...... of magnetic resonance imaging with the high sensitivity and spatial accuracy of positron emission tomography. We have used this technique, together with determination of tissue radioactivity, flow cytometry, and microscopy, to characterize and quantitate the specific accumulation of transferred CD8+ T cells...... was determined by flow cytometry each day for 8 consecutive days after adoptive transfer. From low levels 1 day after injection, their number gradually increased until day 5 when an average of 3.3x10(6) SIINFEKL-specific cells per gram tumor tissue was found. By applying the combined positron emission tomography/magnetic...

  7. Alterations of Regional Cerebral Blood Flow in Tinnitus Patients as Assessed Using Single-Photon Emission Computed Tomography.

    Directory of Open Access Journals (Sweden)

    Takashi Ueyama

    Full Text Available Tinnitus is the perception of phantom sound without an external auditory stimulus. Using neuroimaging techniques, such as positron emission tomography, electroencephalography, magnetoencephalography, and functional magnetic resonance imaging (fMRI, many studies have demonstrated that abnormal functions of the central nervous system are closely associated with tinnitus. In our previous research, we reported using resting-state fMRI that several brain regions, including the rectus gyrus, cingulate gyrus, thalamus, hippocampus, caudate, inferior temporal gyrus, cerebellar hemisphere, and medial superior frontal gyrus, were associated with tinnitus distress and loudness. To reconfirm these results and probe target regions for repetitive transcranial magnetic stimulation (rTMS, we investigated the regional cerebral blood flow (rCBF between younger tinnitus patients (<60 years old and the age-matched controls using single-photon emission computed tomography and easy Z-score imaging system. Compared with that of controls, the rCBF of tinnitus patients was significantly lower in the bilateral medial superior frontal gyri, left middle occipital gyrus and significantly higher in the bilateral cerebellar hemispheres and vermis, bilateral middle temporal gyri, right fusiform gyrus. No clear differences were observed between tinnitus patients with normal and impaired hearing. Regardless of the assessment modality, similar brain regions were identified as characteristic in tinnitus patients. These regions are potentially involved in the pathophysiology of chronic subjective tinnitus.

  8. Diagnostic role of 18F-fluorodeoxyglucose positron emission tomography for follicular lymphoma with gastrointestinal involvement

    Institute of Scientific and Technical Information of China (English)

    Masaya Iwamuro; Hiroyuki Okada; Katsuyoshi Takata; Katsuji Shinagawa; Shigeatsu Fujiki; Junji Shiode; Atsushi Imagawa

    2012-01-01

    AIM:To investigate the capacity for 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)to evaluate patients with gastrointestinal lesions of follicular lymphoma.@@METHODS:This retrospective case series consisted of 41 patients with follicular lymphoma and gastrointestinal involvement who underwent 18F-FDG-PET and endoscopic evaluations at ten different institutions between November 1996 and October 2011.Data for endoscopic,radiological,and biological examinations performed were retrospectively reviewed from clinical records.A semi-quantitative analysis of 18F-FDG uptake was performed for each involved area by calculating the maximum standardized uptake value (SUVmax).Based on the positivity of 18F-FDG uptake in the gastrointestinal lesions analyzed,patients were subdivided into two groups.To identify potential predictive factors for 18F-FDG positivity,these two groups were compared with respect to gender,age at diagnosis of lymphoma,histopathological grade,pattern of follicular dendritic cells,mitotic rate,clinical stage,soluble interleukin-2 receptor levels detected by 18F-FDG-PET,lactate dehydrogenase (LDH) levels,hemoglobin levelsbone marrow involvement,detectability of gastrointestinal lesions by computed tomography (CT) scanningand follicular lymphoma international prognostic index (FLIPI) risk.@@RESULTS:Involvement of follicular lymphoma in the stomach,duodenum,jejunum,ileum,cecum,colon,and rectum was identified in 1,34,6,3,2,3,and 6patients,respectively.No patient had esophageal involvement.In total,19/41 (46.3%) patients exhibited true-positive 18F-FDG uptake in the lesions present in their gastrointestinal tract.In contrast,false-negative 18F-FDG uptake was detected in 24 patients (58.5%),while false-positive 18F-FDG uptake was detected in 5 patients (12.2%).In the former case,2/19 patients had both 18F-FDG-positive lesions and 18F-FDG-negative lesions in the gastrointestinal tract.In patients with 18F-FDG avidity,the SUVmax value of

  9. The potential of positron emission tomography for intratreatment dynamic lung tumor tracking: A phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jaewon [Department of Electrical Engineering, Stanford University, Stanford, California 94305 and Department of Radiation Oncology, Stanford University, Stanford, California 94305 (United States); Yamamoto, Tokihiro [Department of Radiation Oncology, University of California Davis, Sacramento, California 95817 (United States); Mazin, Samuel R. [RefleXion Medical, Inc., Burlingame, California 94010 (United States); Graves, Edward E. [Department of Radiation Oncology, Stanford University, Stanford, California 94305 (United States); Keall, Paul J., E-mail: paul.keall@sydney.edu.au [Radiation Physics Laboratory, University of Sydney, Sydney, NSW 2006 (Australia)

    2014-02-15

    Purpose: This study aims to evaluate the potential and feasibility of positron emission tomography for dynamic lung tumor tracking during radiation treatment. The authors propose a center of mass (CoM) tumor tracking algorithm using gated-PET images combined with a respiratory monitor and investigate the geometric accuracy of the proposed algorithm. Methods: The proposed PET dynamic lung tumor tracking algorithm estimated the target position information through the CoM of the segmented target volume on gated PET images reconstructed from accumulated coincidence events. The information was continuously updated throughout a scan based on the assumption that real-time processing was supported (actual processing time at each frame ≈10 s). External respiratory motion and list-mode PET data were acquired from a phantom programmed to move with measured respiratory traces (external respiratory motion and internal target motion) from human subjects, for which the ground truth target position was known as a function of time. The phantom was cylindrical with six hollow sphere targets (10, 13, 17, 22, 28, and 37 mm in diameter). The measured respiratory traces consisted of two sets: (1) 1D-measured motion from ten healthy volunteers and (2) 3D-measured motion from four lung cancer patients. The authors evaluated the geometric accuracy of the proposed algorithm by quantifying estimation errors (Euclidean distance) between the actual motion of targets (1D-motion and 3D-motion traces) and CoM trajectories estimated by the proposed algorithm as a function of time. Results: The time-averaged error of 1D-motion traces over all trajectories of all targets was 1.6 mm. The error trajectories decreased with time as coincidence events were accumulated. The overall error trajectory of 1D-motion traces converged to within 2 mm in approximately 90 s. As expected, more accurate results were obtained for larger targets. For example, for the 37 mm target, the average error over all 1D

  10. Measured dose rate constant from oncology patients administered 18F for positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, Brian; Holahan, Brian; Aime, Jean; Humm, John; St Germain, Jean; Dauer, Lawrence T. [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, New York 10065 (United States); Department of Radiology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, New York 10065 (United States); Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, New York 10065 (United States) and Department of Radiology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, New York 10065 (United States); Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, New York 10065 (United States); Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, New York 10065 (United States) and Department of Radiology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, New York 10065 (United States)

    2012-10-15

    Purpose: Patient exposure rate measurements verify published patient dose rate data and characterize dose rates near 2-18-fluorodeoxyglucose ({sup 18}F-FDG) patients. A specific dose rate constant based on patient exposure rate measurements is a convenient quantity that can be applied to the desired distance, injection activity, and time postinjection to obtain an accurate calculation of cumulative external radiation dose. This study reports exposure rates measured at various locations near positron emission tomography (PET) {sup 18}F-FDG patients prior to PET scanning. These measurements are normalized for the amount of administered activity, measurement distance, and time postinjection and are compared with other published data. Methods: Exposure rates were measured using a calibrated ionization chamber at various body locations from 152 adult oncology patients postvoid after a mean uptake time of 76 min following injection with a mean activity of 490 MBq {sup 18}F-FDG. Data were obtained at nine measurement locations for each patient: three near the head, four near the chest, and two near the feet. Results: On contact with, 30 cm superior to and 30 cm lateral to the head, the mean (75th percentile) dose rates per unit injected activity at 60 min postinjection were 0.482 (0.511), 0.135 (0.155), and 0.193 (0.223) {mu}Sv/MBq h, respectively. On contact with, 30 cm anterior to, 30 cm lateral to and 1 m anterior to the chest, the mean (75th percentile) dose rates per unit injected activity at 60 min postinjection were 0.623 (0.709), 0.254 (0.283), 0.190 (0.218), and 0.067 (0.081) {mu}Sv/MBq h respectively. 30 cm inferior and 30 cm lateral to the feet, the mean (75th percentile) dose rates per unit injected activity at 60 min postinjection were 0.024 (0.022) and 0.039 (0.044) {mu}Sv/MBq h, respectively. Conclusions: The measurements for this study support the use of 0.092 {mu}Sv m{sup 2}/MBq h as a reasonable representation of the dose rate anterior from the chest of

  11. Depressed cerebral oxygen metabolism in patients with chronic renal failure. A positron emission tomography study

    Energy Technology Data Exchange (ETDEWEB)

    Hirakata, Hideki; Kanai, Hidetoshi; Nakane, Hiroshi; Fujii, Ken-ichiro; Hirakata, Eriko; Ibayashi, Setsuro; Kuwabara, Yasuo; Deenitchna, S.S.; Fujishima, Masatoshi [Kyushu Univ., Fukuoka (Japan). Graduate School of Medical Sciences

    2001-07-01

    In order to elucidate brain oxygen metabolism in uremic patients, the regional cerebral blood flow (rCBF), oxygen extraction (rOEF) and oxygen metabolism (rCMRO{sub 2}) were measured by positron emission tomography (PET) in both 10 hemodialysis patients (HD: male [m]/female [f]=2/8, age of 49{+-}3 [SEM] years old, HD duration of 113{+-}26 months) and 13 pre-dialysis renal failure patients (CRF: m/f=10/3, age of 61{+-}2 years old, serum creatinine (SCr) of 6.3{+-}1.0 mg/dl). Data were compared with 20 non-uremic subjects (Control: m/f=7/13, age of 62{+-}2 years old, SCr of 0.9{+-}0.1 mg/dl). They had no neurological abnormalities, congestive heart failure, history of cerebrovascular accident, diabetes mellitus, or symptomatic brain lesion on magnetic resonance imaging. The age of HD was significantly younger than the other groups (p<0.02) and the hemoglobin (Hb) levels in both HD (10.5{+-}0.5 g/dl) and CRF (9.8{+-}0.9) were significantly lower than that in Control (13.3{+-}0.3) (p<0.02). In the hemisphere, rCMRO{sub 2} in both HD (1.82{+-}0.10 ml/min/100 g) and CRF (1.95{+-}0.09) showed significantly lower values as compared to Control (2.23{+-}0.05) (p<0.01, respectively). Hemispheric rCBF in HD (35.6{+-}2.1 ml/100 g/min) and in CRF (36.1{+-}2.1) were not different from that in Control (31.8{+-}1.4). Hemispheric rOEF in CRF (45.7{+-}1.6%) was significantly higher than that in Control (40.5{+-}1.2%) (p<0.02), but that in HD (43.7{+-}1.9%) did not increase significantly. These tendencies were similar in all regions of interest, especially in the cerebral cortices, but not in the cerebellum. All PET parameters in the frontal cortices tended to show the lowest value in renal failure patients. For all HD patients, rCBF in both the frontal cortex and the white matter correlated inversely with HD duration (frontal cortex: r=-0.649, p<0.05; white matter: r=-0.706, p<0.02). Based on these data, it is concluded that brain oxygen metabolism is depressed in renal failure

  12. Mechanisms for the recovery of aphasia following stroke. A positron emission tomography study

    Energy Technology Data Exchange (ETDEWEB)

    Warburton, E

    1998-07-01

    Language disorders following stroke are common and are a major source of distress and disability. Most patients show some recovery with time implying the potential for neuronal plasticity within the brain for recovery of language. The mechanisms underlying recovery are poorly understood, making strategies for speech therapy and further investigation of potential therapeutic agents difficult. These studies were designed to explore the cortical re-organisation which underlies at least some language recovery using positron emission tomography (PET). With the rapid developments in PET technology and advances in image data processing it is now well established that language tasks can be studied in terms of responses within brain regions, and interactions between regions. The results can be interpreted with reference to neuropsychological theory and models. Many language activation studies have been performed in the normal brain. Thestudies reported here concentrated on one behavioural task - the verbal fluency task - the strategy being to compare patterns of activation in normal subjects with those in recovered aphasic patients performing the same fluency task. In the first part of this thesis, a detailed PET study of a verb retrieval task was made using different control tasks in normal volunteers. The results show that this task engages a widespread network of regions, predominantly in the left hemisphere i.e. the dorsolateral temporal cortex, the inferolateral temporal cortex and inferior parietal cortex, an extensive area of the dorsolateral prefrontal cortex (LDLPFC), the anterior cingulate and the supplementary motor area (SMA). The experiments using different control tasks suggest that the dorsolateral temporal cortex is involved with auditory and lexical processing of the stimulus nouns and it is demonstrated that observation of an activation in this region is dependent on the particular control task used with the retrieval task. This explains discrepancies

  13. {sup 18}F-Fluoromisonidazole positron emission tomography may differentiate glioblastoma multiforme from less malignant gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Hirata, Kenji; Shiga, Tohru; Tamaki, Nagara [Hokkaido University, Department of Nuclear Medicine, Graduate School of Medicine, Sapporo, Hokkaido (Japan); Terasaka, Shunsuke; Kobayashi, Hiroyuki; Yamaguchi, Shigeru; Houkin, Kiyohiro [Graduate School of Medicine, Hokkaido University, Department of Neurosurgery, Sapporo (Japan); Hattori, Naoya [Graduate School of Medicine, Hokkaido University, Department of Molecular Imaging, Sapporo (Japan); Magota, Keiichi [Hokkaido University Hospital, Department of Radiology, Sapporo (Japan); Tanaka, Shinya [Graduate School of Medicine, Hokkaido University, Department of Cancer Pathology, Sapporo (Japan); Kuge, Yuji [Hokkaido University, Central Institute of Isotope Science, Sapporo (Japan)

    2012-05-15

    Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor and its prognosis is significantly poorer than those of less malignant gliomas. Pathologically, necrosis is one of the most important characteristics that differentiate GBM from lower grade gliomas; therefore, we hypothesized that {sup 18}F fluoromisonidazole (FMISO), a radiotracer for hypoxia imaging, accumulates in GBM but not in lower grade gliomas. We aimed to evaluate the diagnostic value of FMISO positron emission tomography (PET) for the differential diagnosis of GBM from lower grade gliomas. This prospective study included 23 patients with pathologically confirmed gliomas. All of the patients underwent FMISO PET and {sup 18}F-fluorodeoxyglucose (FDG) PET within a week. FMISO images were acquired 4 h after intravenous administration of 400 MBq of FMISO. Tracer uptake in the tumor was visually assessed. Lesion to normal tissue ratios and FMISO uptake volume were calculated. Of the 23 glioma patients, 14 were diagnosed as having GBM (grade IV glioma in the 2007 WHO classification), and the others were diagnosed as having non-GBM (5 grade III and 4 grade II). In visual assessment, all GBM patients showed FMISO uptake in the tumor greater than that in the surrounding brain tissues, whereas all the non-GBM patients showed FMISO uptake in the tumor equal to that in the surrounding brain tissues (p {<=} 0.001). One GBM patient was excluded from FDG PET study because of hyperglycemia. All GBM patients and three of the nine (33%) non-GBM patients showed FDG uptake greater than or equal to that in the gray matter. The sensitivity and specificity for diagnosing GBM were 100 and 100% for FMISO, and 100 and 66% for FDG, respectively. The lesion to cerebellum ratio of FMISO uptake was higher in GBM patients (2.74 {+-} 0.60, range 1.71-3.81) than in non-GBM patients (1.22 {+-} 0.06, range 1.09-1.29, p {<=} 0.001) with no overlap between the groups. The lesion to gray matter ratio of FDG was also

  14. Applications of Beta Particle Detection for Synthesis and Usage of Radiotracers Developed for Positron Emission Tomography

    Science.gov (United States)

    Dooraghi, Alex Abreu

    Positron Emission Tomography (PET) is a noninvasive molecular imaging tool that requires the use of a radioactive compound or radiotracer which targets a molecular pathway of interest. We have developed and employed three beta particle radiation detection systems to advance PET. Specifically, the goals of these systems are to: 1. Automate dispensing of solutions containing a positron emitting isotope. 2. Monitor radioactivity on-chip during synthesis of a positron emitting radiotracer. 3. Assay cellular uptake on-chip of a positron emitting radiotracer. Automated protocols for measuring and dispensing solutions containing radioisotopes are essential not only for providing an optimum environment for radiation workers, but also to ensure a quantitatively accurate workflow. For the first project, we describe the development and performance of a system for automated radioactivity distribution of beta particle emitting radioisotopes such as fluorine-18 (F-18). Key to the system is a radiation detector in-line with a peristaltic pump. The system demonstrates volume accuracy within 5 % for volumes of 20 muL or greater. When considering volumes of 20 muL or greater, delivered radioactivity is in agreement with the requested radioactivity as measured with the dose calibrator. The integration of the detector and pump leads to a flexible system that can accurately dispense solutions containing F-18 in radioactivity concentrations directly produced from a cyclotron (~ 0.1-1 mCi/muL), to low activity concentrations intended for preclinical mouse scans (~ 1-10 muCi/muL), and anywhere in between. Electrowetting on dielectric (EWOD) is an attractive microfluidic platform for batch synthesis of PET radiotracers. Visualization of radioisotopes on-chip is critical for synthesis optimization and technological development. For the second project, we describe the development and performance of a Cerenkov/real-time imaging system for PET radiotracer synthesis on EWOD. We also investigate

  15. The predictive role of interim positron emission tomography for Hodgkin lymphoma treatment outcome is confirmed using the interpretation criteria of the Deauville five-point scale

    DEFF Research Database (Denmark)

    Gallamini, Andrea; Barrington, Sally F; Biggi, Alberto

    2014-01-01

    A retrospective, international, multicenter study was undertaken to assess: (i) the prognostic role of 'interim' positron emission tomography performed during treatment with doxorubicin, bleomycin, vinblastine and dacarbazine in patients with Hodgkin lymphoma; and (ii) the reproducibility...... of the Deauville five-point scale for the interpretation of interim positron emission tomography scan. Two hundred and sixty patients with newly diagnosed Hodgkin lymphoma were enrolled. Fifty-three patients with early unfavorable and 207 with advanced-stage disease were treated with doxorubicin, bleomycin......, vinblastine and dacarbazine ± involved-field or consolidation radiotherapy. Positron emission tomography scan was performed at baseline and after two cycles of chemotherapy. Treatment was not changed according to the results of the interim scan. An international panel of six expert reviewers independently...

  16. 6-[F-18]Fluoro-L-Dihydroxyphenylalanine Positron Emission Tomography Is Superior to Conventional Imaging with I-123-Metaiodobenzylguanidine Scintigraphy, Computer Tomography, and Magnetic Resonance Imaging in Localizing Tumors Causing Catecholamine Excess

    NARCIS (Netherlands)

    Fiebrich, Helle-Brit; Brouwers, Adrienne H.; Kerstens, Michiel N.; Pijl, Milan E. J.; Kema, Ido P.; de Jong, Johan R.; Jager, Pieter L.; Elsinga, Philip H.; Dierckx, Rudi A. J. O.; van der Wal, Jacqueline E.; Sluiter, Wim J.; de Vries, Elisabeth G. E.; Links, Thera P.

    2009-01-01

    Context: Catecholamine excess is rare, but symptoms may be life threatening. Objective: The objective of the study was to investigate the sensitivity of 6-[F-18]fluoro-L-dihydroxyphenylalanine positron emission tomography (F-18-DOPAPET), compared with I-123-metaiodobenzylguanidine (I-123-MIBG) scint

  17. Prospective comparison of computed tomography, diffusion-weighted magnetic resonance imaging and [{sup 11}C]choline positron emission tomography/computed tomography for preoperative lymph node staging in prostate cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Heck, Matthias M.; Retz, Margitta; Nawroth, Roman; Kuebler, Hubert; Maurer, Tobias; Thalgott, Mark; Gschwend, Juergen E. [Technische Universitaet Muenchen, Department of Urology, Klinikum rechts der Isar, Munich (Germany); Souvatzoglou, Michael; Schwaiger, Markus [Technische Universitaet Muenchen, Department of Nuclear Medicine, Klinikum rechts der Isar, Munich (Germany); Gramer, Bettina M.; Rummeny, Ernst J.; Eiber, Matthias [Technische Universitaet Muenchen, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Weirich, Gregor [Technische Universitaet Muenchen, Department of Pathology and Pathologic Anatomy, Klinikum rechts der Isar, Munich (Germany); Rondak, Ina-Christine [Technische Universitaet Muenchen, Institute of Medical Statistics and Epidemiology, Klinikum rechts der Isar, Munich (Germany); Krause, Bernd [Technische Universitaet Muenchen, Department of Nuclear Medicine, Klinikum rechts der Isar, Munich (Germany); Universitaetsmedizin Rostock, Universitaet Rostock, Department of Nuclear Medicine, Rostock (Germany)

    2014-04-15

    The aim of this study was to prospectively compare diffusion-weighted magnetic resonance imaging (DWI) and [{sup 11}C]choline positron emission tomography/computed tomography (PET/CT) with computed tomography (CT) for preoperative lymph node (LN) staging in prostate cancer (PCa) patients. Between June 2010 and May 2012, CT, DWI and [{sup 11}C]choline PET/CT were performed preoperatively in 33 intermediate- and high-risk PCa patients undergoing radical prostatectomy (RP) and extended pelvic lymph node dissection (ePLND) including obturator fossa and internal, external and common iliac fields. Patient- and field-based performance characteristics for all three imaging techniques based on histopathological results are reported. Imaging techniques were compared by means of the area under the curve (AUC). LN metastases were detected in 92 of 1,012 (9 %) LNs from 14 of 33 (42 %) patients. On patient-based analysis, sensitivity, specificity and accuracy for CT were 57, 68 and 64 %, respectively, for DWI were 57, 79 and 70 %, respectively, and for [{sup 11}C]choline PET/CT were 57, 90 and 76 %, respectively. On field-based analysis, these numbers for CT were 47, 94 and 88 %, respectively, for DWI were 56, 97 and 92 %, respectively, and for [{sup 11}C]choline PET/CT were 62, 96 and 92 %, respectively. Neither DWI nor [{sup 11}C]choline PET/CT performed significantly better than CT on pairwise comparison of patient- and field-based results. All three imaging techniques exhibit a rather low sensitivity with less than two thirds of LN metastases being detected on patient- and field-based analysis. Overall diagnostic efficacy did not differ significantly between imaging techniques, whereas distinct performance characteristics, esp. patient-based specificity, were best for [{sup 11}C]choline PET/CT followed by DWI and CT. (orig.)

  18. (/sup 11/C)clorgyline and (/sup 11/C)-L-deprenyl and their use in measuring functional monoamine oxidase activity in the brain using positron emission tomography

    Science.gov (United States)

    Fowler, J.S.; MacGregor, R.R.; Wolf, A.P.

    1986-04-17

    This invention involves a new strategy for imaging the activity of the enzyme monoamine oxidase in the living body by using /sup 11/C-labeled enzyme inhibitors which bind irreversibly to an enzyme as a result of catalysis. By using positron emission tomography to image the distribution of radioactivity produced by the body penetrating radiation emitted by carbon-11, a map of functionally active monoamine oxidase activity is obtained. Clorgyline and L-deprenyl are suicide enzyme inhibitors and irreversibly inhibit monoamine oxidase. When these inhibitors are labeled with carbon-11 they provide selective probes for monoamine oxidase localization and reactivity in vivo using positron emission tomography. 2 figs.

  19. Additional benefit of {sup 18}F-fluorodeoxyglucose integrated positron emission tomography/computed tomography in the staging of oesophageal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Gillies, R.S. [Oxford Cancer and Haematology Centre, Churchill Hospital, Department of Medical Oncology, Oxford (United Kingdom); Oxford Cancer and Haematology Centre, Churchill Hospital, Department of Oesophagogastric Surgery, Oxford (United Kingdom); Middleton, M.R. [Oxford Cancer and Haematology Centre, Churchill Hospital, Department of Medical Oncology, Oxford (United Kingdom); Maynard, N.D. [Oxford Cancer and Haematology Centre, Churchill Hospital, Department of Oesophagogastric Surgery, Oxford (United Kingdom); Bradley, K.M.; Gleeson, F.V. [Oxford Cancer and Haematology Centre, Churchill Hospital, Department of Radiology, Oxford (United Kingdom)

    2011-02-15

    {sup 18}F-fluorodeoxyglucose positron emission tomography (FDG PET) has been shown to improve the accuracy of staging in oesophageal cancer. We assessed the benefit of PET/CT over conventional staging and determined if tumour histology had any significant impact on PET/CT findings. A retrospective cohort study, reviewing the results from 200 consecutive patients considered suitable for radical treatment, undergoing routine PET/CT staging comparing the results from CT and endoscopic ultrasound, as well as multi-disciplinary team records. Adenocarcinoma and squamous cell carcinoma were compared for maximum Standardised Uptake Value (SUV{sub max}), involvement of local lymph nodes and distant metastases. PET/CT provided additional information in 37 patients (18.5%) and directly altered management in 34 (17%): 22 (11%) were upstaged; 15 (7.5%) were downstaged, 12 of whom (6%) received radical treatment. There were 11 false negatives (5.5%) and 1 false positive (0.5%). SUV{sub max} was significantly lower for adenocarcinoma than squamous cell carcinoma (median 9.1 versus 13.5, p = 0.003). Staging with PET/CT offers additional benefit over conventional imaging and should form part of routine staging for oesophageal cancer. Adenocarcinoma and squamous cell carcinoma display significantly different FDG-avidity. (orig.)

  20. Usefulness of {sup 18}F-fluorodeoxyglucose positron emission tomography in follicular lymphoma management; Apport de la tomographie a emission de positons au {sup 18}F-fluorodeoxyglucose dans la prise en charge des lymphomes folliculaires

    Energy Technology Data Exchange (ETDEWEB)

    Le Dortz, L.; Devillers, A.; Prigent, F.; Bahri, H.; Hervouet, T.; Garin, E. [Centre Eugene-Marquis, Service de Medecine Nucleaire, 35 - Rennes (France); Guibert, S. de.; Lamy, T. [CHU de Rennes, Service d' Hematologie, 35 - Rennes (France); Rolland, Y. [Centre Eugene-Marquis, Service de Radiologie, 35 - Rennes (France); Bayat, S. [CHU de Rennes, Dept. d' Information Medicale, 35 - Rennes (France)

    2009-06-15

    Purpose To assess the usefulness of positron emission tomography/computed tomography in staging, prognosis evaluation and re staging of patients with follicular lymphoma. Patients and methods a retrospective study was performed on 45 patients with untreated biopsy-proven follicular lymphoma who underwent F.D.G.-PET/CT and CT before and after chemo-immunotherapy induction treatment (rituximab combined with cyclophosphamide, doxorubicin, vincristine and prednisone). Results PET/CT detected more nodal (+51%) and extra nodal (+89%) lesions than CT. PET/CT changed Ann Arbor stage in eight patients (18%). Five patients (11%) initially considered with early stage (I/II) were finally managed as advanced stage (III/IV). In this study, initial PET/CT was significantly more accurate to identify patients with poor prognosis than F.L.I.P.I.. Poor prognosis was defined as incomplete therapeutic response or early relapse. Accuracy of PET/CT for therapeutic response assessment was significantly higher than that of CT (0.97 vs 0.64), especially because of its ability to identify inactive residual masses. Beside, post-treatment PET/CT was able to predict patients outcome. The median progression free survival (P.F.S.) was 48 months in the PET/CT negative group as compared to 17.2 months for the group with residual uptake (P < 10-4). Conclusion F.D.G.-PET/CT is a very useful tool for staging, assessing prognosis and therapeutic response of patients with follicular lymphoma. (authors)

  1. Usefulness of positron emission tomography (TEP) in the assessment of osteo-articular prosthesis; Utilite de la tomographie par emission de positons (TEP) dans l'etude des protheses osteo-articulaires

    Energy Technology Data Exchange (ETDEWEB)

    Maldonado, A.; Suarez, J.P.; Dominguez, M.L. [Centro PET Complutense, Madrid (Spain)

    2004-12-15

    Joint arthroplasty is performed with increasing frequency as the population ages. Loosening or infection of the prosthesis is a relatively common event that can limit the lifetime of a prosthesis. Accuracy differentiation between aseptic and septic loosening of the prosthesis remains a challenge because of the consequences for patient management. Moreover, an early diagnosis of infected hip prosthesis is very important for optimal and cost-effective management. Various approaches have developed to visualize infection and inflammation by nuclear medicine techniques. Recently positron emission tomography (PET) with fluorine-l8 labelled 2 fluoro-2-deoxyglucose ({sup 18}F-FDG) has been shown to delineate infectious and inflammatory foci with high sensitivity owing to the increased glucose metabolism in inflammatory cells. In this paper we review the role of FDG-PET in this common differential diagnosis in patients with total knee and hip prostheses. Different patterns of FDG-PET interpretation have been described as wed as methodological aspects. (author)

  2. Vasculitis assessment with [{sup 18}F]F.D.G. positron emission tomography; Place de la tomographie par emission de positons (TEP) au [{sup 18}F]FDG dans l'exploration des vascularites

    Energy Technology Data Exchange (ETDEWEB)

    Liozon, E. [CHU Dupuytren, Services de Medecine Interne A, 87 - Limoges (France); Monteil, J. [CHU Dupuytren, Services de Medecine Nucleaire, 87 - Limoges (France)

    2008-10-15

    [{sup 18}F]fluorodeoxyglucose ({sup 18}F.D.G.) positron emission tomography (PET) is a noninvasive metabolic imaging modality that is well suited to the assessment of activity and extent of large vessel vasculitis, such as giant cell arteritis and Takayasu arteritis. PET could be more effective than magnetic resonance imaging in detecting the earliest stages of vascular wall inflammation. The visual grading of vascular [{sup 18}F]F.D.G. uptake makes it possible to discriminate arteritis from atherosclerosis, providing therefore high specificity. High sensitivity can be achieved provided scanning is performed during active inflammatory phase, preferably before starting corticosteroid treatment. Large scale prospective studies are needed to determine the exact value of PET imaging in assessing the large vessel vasculitis outcome and response to immunosuppressive treatment.

  3. Development and applications of TOHR, an original emission tomography system, adapted to small animals; Developpement et applications de TOHR, un systeme original de tomographie d`emission, adapte au petit animal

    Energy Technology Data Exchange (ETDEWEB)

    Ploux, Lydie [Inst. de Physique Nucleaire, Paris-11 Univ., 91 - Orsay (France)

    1997-12-11

    For many neuro-biological studies, it is necessary to link microscopic aspects of the brain`s organization with integrated brain functions. Details of the former are obtained by in vitro and in situ molecular biology techniques, whereas the latter are acquired through behavioural studies. In vivo radio-imaging methods, like emission tomography are the ideal tools to investigate the links between these two levels of brain organization. The work which is presented here focuses on a new approach of emission tomography adapted to small animal studies: TOHR (French, acronym for TOmographe Haute Resolution). The principle is based on the use of a large solid angle, high resolution and high efficiency focusing collimator. High resolution and high signal to noise ratio are improved by using nuclides having a two-photon decay with small angular correlation ({sup 125}I, {sup 123}I, {sup 111}In,...). The image is built step-by-step, by moving the animal relative to the collimator focal point. First, numerical simulation showed the possibility of reaching sub-millimetric resolutions; these results led to the collimator geometry (at present 10 over the 20 faces of an icosahedron, 15 faces in the future). Then, a prototype of TOHR has been built and characterized. Its performance is very close to the numerical prediction: spatial resolution of 1.4 mm and detection efficiency 0.64%. Finally, experiments on a rat thyroid allowed the preparation and realization of the first experiments on a rat striatum. The good quality of these images shows that it is now possible to evaluate TOHR capabilities on a dopaminergic neuron degeneration model in rats in the field of neuro-degenerative disease studies. (author) 51 refs., 76 figs., 28 tabs.

  4. Prediction of traumatic avascular necrosis of the femoral head by single photon emission computerized tomography and computerized tomography: an experimental study in dogs

    Institute of Scientific and Technical Information of China (English)

    SHEN Feng; YAN Zuo-qin; GUO Chang-an; SHI Hong-cheng; GU Yu-shen; ZENG Meng-su; LU Xiao-yu; LIU Jun

    2011-01-01

    Objective: To evaluate the femoral head perfusion and to predict the traumatic avascular necrosis (AVN) of the femoral head by single photon emission computerized tomography and computerized tomography (SPECT/CT). Methods: Totally 18 adult beagle dogs were divided randomly into three equal-sized (n=6) groups. Subsequently different degrees of ischemia model were developed by destroying blood vessels of the femoral head. The left hip received sham operation as normal control and the right hip underwent blood interruption. In Group A, the ligamentum teres was cut off. In Group B, the marrow cavity of the right femoral neck was destroyed while in Group C, the soft tissues at the base of the femoral neck were stripped in addition to the resection of the ligamentum teres and destruction of the marrow cavity. Three hours after surgery, SPECT/ CT was performed. Laser Doppler Flowmetry (LDF) measurements were also obtained at three different time points (before operation, immediately and three hours after operation) in order to assess the change process of blood supply to the femoral head. Results: SPECT/CT showed no significant difference in the radionuclide uptake between the right and left femoral heads in Group A (t=-0.09, P=0.94) and Group B (t= 0.52, P=0.62). However, in Group C, it was 261 ±62 for the right femoral head, only 12% of that in the left femoral head. LDF measurements indicated that the femoral head perfusion was decreased from (45.0±3.3) PU to (39.1±3.7) PU in Group A, from (44.0±2.7) PU to (34.3±2.6) PU in Group B, and from (47.3 ±2.1) PU to (4.96±0.6) PU in Group C immediately after operation. However, the perfusion was restored and returned to normal values three hours after operation except in Group C. Conclusion: SPECT/CT could assess the perfusion of the femoral head semiquantitatively, which might be useful in predicting the development of traumatic AVN.

  5. A comparison study of 11C-methionine and 18F-fluorodeoxyglucose positron emission tomography-computed tomography scans in evaluation of patients with recurrent brain tumors

    Science.gov (United States)

    Sharma, Rajnish; D’Souza, Maria; Jaimini, Abhinav; Hazari, Puja Panwar; Saw, Sanjeev; Pandey, Santosh; Singh, Dinesh; Solanki, Yachna; Kumar, Nitin; Mishra, Anil K.; Mondal, Anupam

    2016-01-01

    Introduction: 11C-methonine ([11C]-MET) positron emission tomography-computed tomography (PET-CT) is a well-established technique for evaluation of tumor for diagnosis and treatment planning in neurooncology. [11C]-MET reflects amino acid transport and has been shown to be more sensitive than magnetic resonance imaging (MRI) in stereotactic biopsy planning. This study compared fluorodeoxyglucose (FDG) PET-CT and MET PET-CT in the detection of various brain tumors. Materials and Methods: Sixty-four subjects of brain tumor treated by surgery, chemotherapy, and/or radiotherapy were subjected to [18F]-FDG, [11C]-MET, and MRI scan. The lesion was analyzed semiquantitatively using tumor to normal contralateral ratio. The diagnosis was confirmed by surgery, stereotactic biopsy, clinical follow-up, MRI, or CT scans. Results: Tumor recurrence was found in 5 out of 22 patients on [F-18] FDG scan while [11C]-MET was able to detect recurrence in 18 out of 22 patients in low-grade gliomas. Two of these patients were false positive for the presence of recurrence of tumor and later found to be harboring necrosis. Among oligodendroglioma, medulloblastoma and high-grade glioma out of 42 patients 39 were found to be concordant MET and FDG scans. On semiquantitative analysis, mean T/NT ratio was found to be 2.96 ± 0.94 for lesions positive for recurrence of tumors and 1.18 ± 0.74 for lesions negative for recurrence of tumor on [11C]-MET scan. While the ratio for FDG scan on semiquantitative analysis was found to be 2.05 ± 1.04 for lesions positive for recurrence of tumors and 0.52 ± 0.15 for lesions negative for recurrence of tumors. Conclusion: The study highlight that [11C]-MET is superior to [18F]-FDG PET scans to detect recurrence in low-grade glioma. A cut-off value of target to nontarget value of 1.47 is a useful parameter to distinguish benign from malignant lesion on an [11C]-MET Scan. Both [18F]-FDG and [11C]-MET scans were found to be useful in high-grade astrocytoma

  6. CyberKnife radiosurgery for inoperable stage IA non-small cell lung cancer: 18F-fluorodeoxyglucose positron emission tomography/computed tomography serial tumor response assessment

    Directory of Open Access Journals (Sweden)

    Chang Thomas

    2010-02-01

    Full Text Available Abstract Objective To report serial 18F-fluorodeoxyglucose (18F-FDG positron emission tomography (PET/computed tomography (CT tumor response following CyberKnife radiosurgery for stage IA non-small cell lung cancer (NSCLC. Methods Patients with biopsy-proven inoperable stage IA NSCLC were enrolled into this IRB-approved study. Targeting was based on 3-5 gold fiducial markers implanted in or near tumors. Gross tumor volumes (GTVs were contoured using lung windows; margins were expanded by 5 mm to establish the planning treatment volumes (PTVs. Doses ranged from 42-60 Gy in 3 equal fractions. 18F-FDG PET/CT was performed prior to and at 3-6-month, 9-15 months and 18-24 months following treatment. The tumor maximum standardized uptake value (SUVmax was recorded for each time point. Results Twenty patients with an average maximum tumor diameter of 2.2 cm were treated over a 3-year period. A mean dose of 51 Gy was delivered to the PTV in 3 to 11 days (mean, 7 days. The 30-Gy isodose contour extended an average of 2 cm from the GTV. At a median follow-up of 43 months, the 2-year Kaplan-Meier overall survival estimate was 90% and the local control estimate was 95%. Mean tumor SUVmax before treatment was 6.2 (range, 2.0 to 10.7. During early follow-up the mean tumor SUVmax remained at 2.3 (range, 1.0 to 5.7, despite transient elevations in individual tumor SUVmax levels attributed to peritumoral radiation-induced pneumonitis visible on CT imaging. At 18-24 months the mean tumor SUVmax for controlled tumors was 2.0, with a narrow range of values (range, 1.5 to 2.8. A single local failure was confirmed at 24 months in a patient with an elevated tumor SUVmax of 8.4. Conclusion Local control and survival following CyberKnife radiosurgery for stage IA NSCLC is exceptional. Early transient increases in tumor SUVmax are likely related to radiation-induced pneumonitis. Tumor SUVmaxvalues return to background levels at 18-24 months, enhancing 18F-FDG PET

  7. Detection of internal mammary lymph node metastasis with {sup 18}F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with stage III breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Min Jung; Lee, Jong Jin; Kim, Hye Ok; Chae, Sun-Young; Ryu, Jin-Sook; Moon, Dae Hyuk [University of Ulsan College of Medicine, Asan Medical Center, Department of Nuclear Medicine, Songpa-gu, Seoul (Korea, Republic of); Park, Seol Hoon [Ulsan University Hospital, Department of Nuclear Medicine, Ulsan (Korea, Republic of); Ahn, Sei Hyun; Lee, Jong Won; Son, Byung Ho [University of Ulsan College of Medicine, Asan Medical Center, Department of Surgery, Seoul (Korea, Republic of); Gong, Gyung-Yub [University of Ulsan College of Medicine, Asan Medical Center, Department of Pathology, Seoul (Korea, Republic of)

    2014-03-15

    The present study assessed the positive predictive value (PPV) of {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for the detection of internal mammary node (IMN) metastasis in patients with clinical stage III breast cancer. Patients who were diagnosed with clinical stage III breast cancer and underwent pretreatment {sup 18}F-FDG PET/CT were retrospectively analyzed. The {sup 18}F-FDG PET/CT scans were prospectively reviewed by two board-certified nuclear medicine physicians in a blinded manner. The intensities of IMNs were graded into four categories (no activity and lower, similar, and higher activities than that of the mediastinal blood pool). IMNs were measured from the combined CT (largest diameter of the short axis). Histologic data of the IMNs were obtained by ultrasonography-guided fine-needle aspiration biopsy or surgical excision. The PPV was calculated for pathologically confirmed IMNs. Visual grade, maximum standardized uptake values (SUV{sub max}), and sizes were analyzed according to the pathology results. There were 249 clinical stage III breast cancer patients (age 48.0 ± 10.1 years, range 26-79 years) who had undergone initial {sup 18}F-FDG PET/CT prior to treatment. Excluding 33 cases of stage IV breast cancer, 62 of 216 patients had visible IMNs on {sup 18}F-FDG PET/CT, and histologic confirmation was obtained in 31 patients. There were 27 metastatic and four nonmetastatic nodes (PPV 87.1 %). Metastatic nodes mostly presented with visual grade 3 (83.9 %), and SUV{sub max} and size were 3.5 ± 4.3 and 5.6 ± 2.0 mm, respectively. {sup 18}F-FDG PET/CT has a high PPV for IMN metastasis in clinical stage III breast cancer, indicating the possibility of metastasis in IMNs with FDG uptake similar to/lower than that of the blood pool or small-sized nodes. (orig.)

  8. [18F]-Fluoromisonidazole Positron Emission Tomography/Computed Tomography Visualization of Tumor Hypoxia in Patients With Chordoma of the Mobile and Sacrococcygeal Spine

    Energy Technology Data Exchange (ETDEWEB)

    Cheney, Matthew D., E-mail: mcheney@lroc.harvard.edu [Harvard Radiation Oncology Program, Boston, Massachusetts (United States); Chen, Yen-Lin [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Lim, Ruth [Department of Diagnostic Radiology, Massachusetts General Hospital, Boston, Massachusetts (United States); Winrich, Barbara K.; Grosu, Anca L.; Trofimov, Alexei V. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Depauw, Nicolas [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Centre of Medical Radiation Physics, University of Wollongong, Wollongong, NSW (Australia); Shih, Helen A. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Schwab, Joseph H.; Hornicek, Francis J. [Department of Orthopedic Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); DeLaney, Thomas F. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

    2014-12-01

    Purpose: To investigate [18F]-fluoromisonidazole positron emission tomography/computed tomography (FMISO-PET/CT) detection of targetable hypoxic subvolumes (HSVs) in chordoma of the mobile or sacrococcygeal spine. Methods and Materials: A prospective, pilot study of 20 patients with primary or locally recurrent chordoma of the mobile or sacrococcygeal spine treated with proton or combined proton/photon radiation therapy (RT) with or without surgery was completed. The FMISO-PET/CT was performed before RT and after 19.8-34.2 GyRBE (relative biologic effectiveness). Gross tumor volumes were delineated and HSVs defined including voxels with standardized uptake values ≥1.4 times the muscle mean. Clinical characteristics and treatments received were compared between patients with and without HSVs. Results: The FMISO-PET/CT detected HSVs in 12 of 20 patients (60%). Baseline and interval HSV spatial concordance varied (0%-94%). Eight HSVs were sufficiently large (≥5 cm{sup 3}) to potentially allow an intensity modulated proton therapy boost. Patients with HSVs had significantly larger gross tumor volumes (median 410.0 cm{sup 3} vs 63.4 cm{sup 3}; P=.02) and were significantly more likely to have stage T2 tumors (5 of 12 vs 0 of 8; P=.04). After a median follow-up of 1.8 years (range, 0.2-4.4 years), a local recurrence has yet to be observed. Three patients developed metastatic disease, 2 with HSVs. Conclusions: Detection of targetable HSVs by FMISO-PET/CT within patients undergoing RT with or without surgery for treatment of chordoma of the mobile and sacrococcygeal spine is feasible. The study's inability to attribute interval HSV changes to treatment, rapidly changing hypoxic physiology, or imaging inconsistencies is a limitation. Further study of double-baseline FMISO-PET/CT and hypoxia-directed RT dose escalation, particularly in patients at high risk for local recurrence, is warranted.

  9. Prognostic Significance of Tumor Response as Assessed by Sequential {sup 18}F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography During Concurrent Chemoradiation Therapy for Cervical Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Dongryul [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Lee, Jeong Eun [Department of Radiation Oncology, Kyungpook National University School of Medicine, Daegu (Korea, Republic of); Huh, Seung Jae, E-mail: sj5201.huh@samsung.com [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Park, Won [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Nam, Heerim [Department of Radiation Oncology, Kangbuk Samsung Hospital, Seoul (Korea, Republic of); Choi, Joon Young; Kim, Byung-Tae [Department of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2013-11-01

    Purpose: To investigate the prognostic role of metabolic response by the use of serial sets of positron emission tomography/computed tomography (PET/CT) in patients with cervical cancer who were treated with concurrent chemoradiation therapy (CCRT). Methods and Materials: A total of 60 patients who were treated with CCRT between February 2009 and December 2010 were analyzed. Three sequential PET/CT images were acquired for each patient: pre-CCRT, during-CCRT at 4 weeks of CCRT, and 1 month post-CCRT PET/CT. Metabolic responses were assessed qualitatively. The percentage changes in the maximum values of standardized uptake value (ΔSUV{sub max}%) from the PET/CT images acquired pre-CCRT and during-CCRT were calculated. Receiver operating characteristic (ROC) curve analysis was performed to evaluate whether ΔSUV{sub max}% could predict complete response (CR) on the post-CCRT PET/CT and to identify the best cutoff value. Prognostic factors of progression-free survival (PFS) were analyzed. Results: During-CCRT PET/CT showed that 8 patients (13%) had CR, and the other 52 patients (87%) had partial response (PR). On the post-CCRT PET/CT, 43 patients (73%) had CR, 12 patients (20%) had PR, and 4 patients (7%) had progressive disease. The average SUV{sub max} in primary tumors was 16.3 (range, 6.4-53.0) on the pre-CCRT PET/CT images and 5.3 (range, 0-19.4) on the during-CCRT PET/CT images. According to ROC curve analysis, ΔSUV{sub max}% could predict CR response on post-CCRT PET/CT (P<.001, cutoff value of 59.7%). In all patients, the PFS rate was 71.9% at 2 years. Multivariate analysis showed that ΔSUV{sub max}% ≥60% (P=.045) and CR response on the post-CCRT PET/CT (P=.012) were statistically significant predictors of PFS. Conclusion: Metabolic responses on the during-CCRT images at 4 weeks of treatment and 1-month post-CCRT PET/CT images may predict treatment outcomes in patients with cervical cancer. ΔSUV{sub max}% ≥60% at 4 weeks of CCRT may predict CR response

  10. Cervical lymph node hyperplasia on [{sup 18}F]-fluorodeoxyglucose positron emission tomography/computed tomography scan after treatment of children and adolescents with malignant lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Ying-Ying, E-mail: huyy@sysucc.org.cn; Zhang, Xu, E-mail: zhangxu2@sysucc.org.cn; Long, Wen, E-mail: longwen2@sysucc.org.cn; Lin, Xiao-Ping, E-mail: linxp@sysucc.org.cn; Zhang, Ya-Rui, E-mail: zhangyr@sysucc.org.cn; Li, Yuan-Hua, E-mail: liyh@sysucc.org.cn; Xiao, Zi-Zheng, E-mail: xiaozzh@sysucc.org.cn; Zheng, Rong-Liang, E-mail: zhengrl@sysucc.org.cn; Liang, Pei-Yan, E-mail: liangpy@sysucc.org.cn; Fan, Wei, E-mail: fanwei@sysucc.org.cn

    2015-07-15

    Highlights: • Cervical lymph node hyperplasia is a benign processes. • Lymph node hyperplasia found in treated children and adolescents with lymphoma. • We define imaging manifestations of cervical lymph node hyperplasia in PET/CT. • Awareness of lymph node hyperplasia avoid invasive procedures and over-treatment. - Abstract: Purpose: To define imaging manifestations and clinical prognosis of cervical lymph node hyperplasia using [{sup 18}F]-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) scanning after treatment of children and adolescents with malignant lymphoma. Methods: Children and adolescent patients with malignant lymphoma who had high FDG uptake in their cervical lymph nodes via PET/CT after treatment, which was not due to tumor recurrence or residue, were retrospectively analyzed. Results: Twenty-seven patients with a median age of 12 years were included; 11 had Hodgkin's disease and 16 had non-Hodgkin's lymphoma. The time from PET/CT scan to completion of therapy was 1–36 months, 85.2% (23/27) of which took place within 12 months. Three patients had confirmed lymph node follicular hyperplasia by biopsy, while all 27 patients achieved disease-free survival during the follow-up period. The maximum standardized uptake values (SUV{sub max}) of cervical lymph nodes were 2.2–16.2 and the maximum short axis ranged from 0.3 to 1.2 cm. Cervical lymph node hyperplasia was noted in neck levels I–V, and neck level II bilaterally had the highest incidence (100%). Bilateral cervical lymph node hyperplasia was symmetrical in terms of both the SUV{sub max} and affected locations. Thymic hyperplasia and nasopharyngeal lymphoid hyperplasia were both observed in 24 patients (88.9%). There was no relationship in terms of the SUV{sub max} between cervical lymph nodes and thymic tissue, cervical nodes or nasopharyngeal lymphoid tissue. Conclusion: Cervical lymph node hyperplasia with high FDG uptake on PET/CT scans found

  11. High resolution gamma detector for small-animal positron emission tomography

    Science.gov (United States)

    Ling, Tao

    In this study, the performance of continuous miniature crystal element (cMiCE) detectors with LYSO crystals of different thickness were investigated. Potential designs of a cMiCE small animal positron emission tomography scanner were also evaluated by an analytical simulation approach. The cMiCE detector was proposed as a high sensitivity, low cost alternative to the prevailing discrete crystal detectors. A statistics based positioning (SBP) algorithm was developed to solve the scintillation position estimation problem and proved to be successful on a cMiCE detector with a 4 mm thick crystal. By assuming a Gaussian distribution, the distributions of the photomultiplier signals could be characterized by mean and variance, which are functions of scintillation position. After calibrating the detector on a grid of locations, a 2D table of the mean and variance can be built. The SBP algorithm searches the tables to find the location that maximizes the likelihood between the mean and variance of known positions and the incoming scintillation event. In this work, the performance of the SBP algorithm on cMiCE detectors with thicker crystals (6 and 8 mm) was studied. The stopping power of a cMiCE detector is 40% and 49% for 6 and 8 mm thick crystals respectively. The intrinsic spatial resolution is 1.2 mm and 1.4 mm FWHM for the center and corner sections of a 6 mm thick crystal detector, and 1.3 mm and 1.6 mm for center and corner of an 8 mm thick crystal detector. These results demonstrate that the cMiCE detector is a promising candidate for high resolution, high sensitivity PET applications. A maximum-likelihood (ML) clustering method was developed to empirically separate the experimental data set into two to four subgroups according to the depth-of-interaction of the detected photons. This method enabled us to build 2-DOI lookup tables (LUT) (mean and variance lookup tables for front group and back group). Using the 2-DOI SBP LUTs, the scintillation position and DOI

  12. Dystrophic calcification in muscles of legs in calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia syndrome: Accurate evaluation of the extent with (99m)Tc-methylene diphosphonate single photon emission computed tomography/computed tomography.

    Science.gov (United States)

    Chakraborty, Partha Sarathi; Karunanithi, Sellam; Dhull, Varun Singh; Kumar, Kunal; Tripathi, Madhavi

    2015-01-01

    We present the case of a 35-year-old man with calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly and telangiectasia variant scleroderma who presented with dysphagia, Raynaud's phenomenon and calf pain. (99m)Tc-methylene diphosphonate bone scintigraphy was performed to identify the extent of the calcification. It revealed extensive dystrophic calcification in the left thigh and bilateral legs which was involving the muscles and was well-delineated on single photon emission computed tomography/computed tomography. Calcinosis in scleroderma usually involves the skin but can be found in deeper periarticular tissues. Myopathy is associated with a poor prognosis.

  13. Initial Assessment of β3-Adrenoceptor-Activated Brown Adipose Tissue in Streptozotocin-Induced Type 1 Diabetes Rodent Model Using [18F]Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography

    OpenAIRE

    Aparna Baranwal; M. Reza Mirbolooki; Jogeshwar Mukherjee

    2015-01-01

    Metabolic activity of brown adipose tissue (BAT) is activated by β3-adrenoceptor agonists and norepinephrine transporter (NET) blockers and is measurable using [18F]fluorodeoxyglucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) in rats. Using the streptozotocin (STZ)-treated rat model of type 1 diabetes mellitus (T1DM), we investigated BAT activity in this rat model under fasting and nonfasting conditions using [18F]FDG PET/CT. Drugs that enhance BAT activity may have...

  14. Dynamic 18F-fluorodeoxyglucose positron emission tomography/CT in hibernoma: enhanced tracer uptake mimicking liposarcoma

    Institute of Scientific and Technical Information of China (English)

    Christos; Sachpekidis; Safwan; Roumia; Matthias; Schwarzbach; Antonia; Dimitrakopoulou-Strauss

    2013-01-01

    We report on two cases of patients with fat-equivalent masses in computed tomography(CT),referred to our department for dynamic positron emission tomography/CT(dPET/CT)with18F-fluorodeoxyglucose(18FFDG)in order to investigate their dignity.Both qualitative and quantitative information,as derived from dPET/CTs,couldn’t exclude a high-grade liposarcoma:Visual evaluation,revealed a large hypermetabolic focus of intense18F-FDG uptake in each patient(average SUVs 8.3 and 11.3).Regression-based parametric imaging demonstrated an enhanced distribution volume,which correlates to perfusion,and a high phosphorylation rate that correlates to cell viability.Kinetic analysis,based on a two-tissue compartment model demonstrated an enhanced FDG transport k1and an enhanced phosphorylation rate k3.A non-compartmental approach based on fractal dimension revealed also enhanced values.However,final diagnosis was based on biopsy,which revealed hibernoma,a benign brown fat tumor.Brown adipose contains increased numbers of mitochondria and a high-rate of glucose metabolism.Therefore,they have increased FDG uptake.The evaluation of lipomatous lesions on CT,with high FDG uptake,should include the possibility of hibernoma as a differential diagnosis.

  15. 18-F fluorodeoxyglucose uptake in positron emission tomography as a pathological grade predictor for renal clear cell carcinomas

    Energy Technology Data Exchange (ETDEWEB)

    Noda, Yoshifumi; Goshima, Satoshi; Kondo, Hiroshi; Watanabe, Haruo; Kawada, Hiroshi; Kawai, Nobuyuki; Tanahashi, Yukichi [Gifu University Hospital, Department of Radiology, Gifu (Japan); Kanematsu, Masayuki [Gifu University Hospital, Department of Radiology, Gifu (Japan); Gifu University Hospital, Department of Radiology Services, Gifu (Japan); Suzui, Natsuko [Gifu University Hospital, Department of Pathology, Gifu (Japan); Hirose, Yoshinobu [Osaka Medical College, Department of Pathology, Osaka (Japan); Matsunaga, Kengo [Kizawa Memorial Hospital, Department of Pathology, Minokamo (Japan); Nishibori, Hironori [Kizawa Memorial Hospital, Department of Radiology, Minokamo (Japan); Bae, Kyongtae T. [University of Pittsburgh Medical Center, Department of Radiology, Pittsburgh, PA (United States)

    2015-10-15

    To evaluate the usefulness of Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18-F FDG-PET/CT) in the prediction of Fuhrman pathological grades of renal clear cell carcinoma (cRCC). This retrospective study was approved by our institutional review board, and written informed consent was waived. Thirty-one patients with pathologically proven cRCC underwent 18-F FDG-PET/CT for tumour staging. Maximum standardized uptake value of cRCC (tumour SUV{sub max}) and mean SUV of the liver and spleen (liver and spleen SUV{sub mean}) were measured by two independent observers. Tumour SUV{sub max}, tumour-to-liver SUV ratio, and tumour-to-spleen SUV ratio were correlated with the pathological grades. Logistic analysis demonstrated that only the tumour-to-liver SUV ratio was a significant parameter for differentiating high-grade (Fuhrman grades 3 and 4) tumours from low-grade (Fuhrman grades 1 and 2) tumours (P = 0.007 and 0.010 for observers 1 and 2, respectively). Sens