Science.gov

Sample records for 99mtc-hmpao brain spect

  1. Brain SPECT quantitation in clinical diagnosis

    SciTech Connect

    Hellman, R.S.

    1991-12-31

    Methods to quantitate SPECT data for clinical diagnosis should be chosen so that they take advantage of the lessons learned from PET data. This is particularly important because current SPECT high-resolution brain imaging systems now produce images that are similar in resolution to those generated by the last generation PET equipment (9 mm FWHM). These high-resolution SPECT systems make quantitation of SPECT more problematic than earlier. Methodology validated on low-resolution SPECT systems may no longer be valid for data obtained with the newer SPECT systems. For example, in patients with dementia, the ratio of parietal to cerebellar activity often was studied. However, with new instruments, the cerebellum appears very different: discrete regions are more apparent. The large cerebellar regions usually used with older instrumentation are of an inappropriate size for the new equipment. The normal range for any method of quantitation determined using older equipment probably changes for data obtained with new equipment. It is not surprising that Kim et al. in their simulations demonstrated that because of the finite resolution of imaging systems, the ability to measure pure function is limited, with {open_quotes}anatomy{close_quotes} and {open_quotes}function{close_quotes} coupled in a {open_quotes}complex nonlinear way{close_quotes}. 11 refs.

  2. Rodent brain imaging with SPECT/CT

    SciTech Connect

    Seo, Youngho; Gao, D.-W.; Hasegawa, Bruce H.; Dae, Michael W.; Franc, Benjamin L.

    2007-04-15

    We evaluated methods of imaging rat models of stroke in vivo using a single photon emission computed tomography (SPECT) system dedicated to small animal imaging (X-SPECT{sup TM}, Gamma Medica-Ideas, Northridge, CA). An animal model of ischemic stroke was developed for in vivo SPECT/CT imaging using the middle cerebral artery occlusion (MCAO) technique. The presence of cerebral ischemia was verified in ex vivo studies using triphenyltetrazolium chloride (TTC) staining. In vivo radionuclide imaging of cerebral blood flow was performed in rats following MCAO using dynamic planar imaging of {sup 99m}Tc-exametazime with parallel hole collimation. This was followed immediately by in vivo radionuclide imaging of cerebral blood flow with {sup 99m}Tc-exametazime in the same animals using 1-mm pinhole SPECT. Correlated computed tomography imaging was performed to localize radiopharmaceutical uptake. The animals were allowed to recover and ex vivo autoradiography was performed with separate administration of {sup 99m}Tc-exametazime. Time activity curve of {sup 99m}Tc-exametazime showed that the radiopharmaceutical uptake could be maintained for over 9 min. The activity would be expected to be relatively stable for a much longer period, although the data were only obtained for 9 min. TTC staining revealed sizable infarcts by visual observation of inexistence of TTC stain in infracted tissues of MCAO rat brains. In vivo SPECT imaging showed cerebral blood flow deficit in the MCAO model, and the in vivo imaging result was confirmed with ex vivo autoradiography. We have demonstrated a capability of imaging regions of cerebral blood flow deficit in MCAO rat brains in vivo using a pinhole SPECT dedicated to small animal imaging.

  3. 3D quantitative analysis of brain SPECT images

    NASA Astrophysics Data System (ADS)

    Loncaric, Sven; Ceskovic, Ivan; Petrovic, Ratimir; Loncaric, Srecko

    2001-07-01

    The main purpose of this work is to develop a computer-based technique for quantitative analysis of 3-D brain images obtained by single photon emission computed tomography (SPECT). In particular, the volume and location of ischemic lesion and penumbra is important for early diagnosis and treatment of infracted regions of the brain. SPECT imaging is typically used as diagnostic tool to assess the size and location of the ischemic lesion. The segmentation method presented in this paper utilizes a 3-D deformable model in order to determine size and location of the regions of interest. The evolution of the model is computed using a level-set implementation of the algorithm. In addition to 3-D deformable model the method utilizes edge detection and region growing for realization of a pre-processing. Initial experimental results have shown that the method is useful for SPECT image analysis.

  4. In Vivo Dosimetry Of Patients Submitted To Brain Spect Studies

    NASA Astrophysics Data System (ADS)

    Cruz-Cortés, D.; Azorín, J.; Saucedo, V. M.

    2004-09-01

    Single photon emission computed tomography (SPECT) is a diagnosis technique which allows to visualize a three dimensional distribution of a radioactive material in the brain. This technique is used for evaluating the blood flux and the metabolic function of the diverse brain regions and is very useful to diagnostic several pathologies such as Alzheimer disease, tumors, epilepsy brain hemorrhages, etc. The radioactive tracer used is 99mTc-labeled hexamethylpropyleneamineoxime (99mTc-HMPAO). We present the results obtained from measurements performed in the chest, back and skull of patients submitted to brain SPECT studies during two hours using home-made LiF:Mg,Cu,P+PTFE thermoluminescent dosimeters. Results obtained showed that the dose received by the patients during two hours are lower than 0.3 mGy.

  5. Collimator design for a multipinhole brain SPECT insert for MRI.

    PubMed

    Van Audenhaege, Karen; Van Holen, Roel; Vanhove, Christian; Vandenberghe, Stefaan

    2015-11-01

    Brain single photon emission computed tomography (SPECT) imaging is an important clinical tool, with unique tracers for studying neurological diseases. Nowadays, most commercial SPECT systems are combined with x-ray computed tomography (CT) in so-called SPECT/CT systems to obtain an anatomical background for the functional information. However, while CT images have a high spatial resolution, they have a low soft-tissue contrast, which is an important disadvantage for brain imaging. Magnetic resonance imaging (MRI), on the other hand, has a very high soft-tissue contrast and does not involve extra ionizing radiation. Therefore, the authors designed a brain SPECT insert that can operate inside a clinical MRI. The authors designed and simulated a compact stationary multipinhole SPECT insert based on digital silicon photomultiplier detector modules, which have shown to be MR-compatible and have an excellent intrinsic resolution (0.5 mm) when combined with a monolithic 2 mm thick LYSO crystal. First, the authors optimized the different parameters of the SPECT system to maximize sensitivity for a given target resolution of 7.2 mm in the center of the field-of-view, given the spatial constraints of the MR system. Second, the authors performed noiseless simulations of two multipinhole configurations to evaluate sampling and reconstructed resolution. Finally, the authors performed Monte Carlo simulations and compared the SPECT insert with a clinical system with ultrahigh-resolution (UHR) fan beam collimators, based on contrast-to-noise ratio and a visual comparison of a Hoffman phantom with a 9 mm cold lesion. The optimization resulted in a stationary multipinhole system with a collimator radius of 150.2 mm and a detector radius of 172.67 mm, which corresponds to four rings of 34 diSPM detector modules. This allows the authors to include eight rings of 24 pinholes, which results in a system volume sensitivity of 395 cps/MBq. Noiseless simulations show sufficient axial

  6. Collimator design for a multipinhole brain SPECT insert for MRI

    SciTech Connect

    Van Audenhaege, Karen; Van Holen, Roel; Vanhove, Christian; Vandenberghe, Stefaan

    2015-11-15

    Purpose: Brain single photon emission computed tomography (SPECT) imaging is an important clinical tool, with unique tracers for studying neurological diseases. Nowadays, most commercial SPECT systems are combined with x-ray computed tomography (CT) in so-called SPECT/CT systems to obtain an anatomical background for the functional information. However, while CT images have a high spatial resolution, they have a low soft-tissue contrast, which is an important disadvantage for brain imaging. Magnetic resonance imaging (MRI), on the other hand, has a very high soft-tissue contrast and does not involve extra ionizing radiation. Therefore, the authors designed a brain SPECT insert that can operate inside a clinical MRI. Methods: The authors designed and simulated a compact stationary multipinhole SPECT insert based on digital silicon photomultiplier detector modules, which have shown to be MR-compatible and have an excellent intrinsic resolution (0.5 mm) when combined with a monolithic 2 mm thick LYSO crystal. First, the authors optimized the different parameters of the SPECT system to maximize sensitivity for a given target resolution of 7.2 mm in the center of the field-of-view, given the spatial constraints of the MR system. Second, the authors performed noiseless simulations of two multipinhole configurations to evaluate sampling and reconstructed resolution. Finally, the authors performed Monte Carlo simulations and compared the SPECT insert with a clinical system with ultrahigh-resolution (UHR) fan beam collimators, based on contrast-to-noise ratio and a visual comparison of a Hoffman phantom with a 9 mm cold lesion. Results: The optimization resulted in a stationary multipinhole system with a collimator radius of 150.2 mm and a detector radius of 172.67 mm, which corresponds to four rings of 34 diSPM detector modules. This allows the authors to include eight rings of 24 pinholes, which results in a system volume sensitivity of 395 cps/MBq. Noiseless simulations

  7. Thallium-201 SPECT imaging of brain tumors: Methods and results

    SciTech Connect

    Kim, K.T.; Black, K.L.; Marciano, D.; Mazziotta, J.C.; Guze, B.H.; Grafton, S.; Hawkins, R.A.; Becker, D.P. )

    1990-06-01

    Recent studies suggest that thallium-201 ({sup 201}Tl) planar scans of brain tumors more accurately reflect viable tumor burden than CT, MRI, or radionuclide studies with other single-photon emitting compounds. We have previously reported the utility of {sup 201}Tl SPECT index in distinguishing low- from high-grade gliomas elsewhere. Here we describe the technical considerations of deriving a simple {sup 201}Tl index, based on uptake in the tumor normalized to homologous contralateral tissue, from SPECT images of brain tumors. We evaluated the importance of consistently correcting for tissue attenuation, as it may achieve better lesion discrimination on qualitative inspection, and the methodologic limitations imposed by partial volume effects at the limits of resolution.

  8. Dual-headed SPECT for awake animal brain imaging

    SciTech Connect

    Lee, Seung Joon; Weisenberger, A G; McKisson, J; Goddard Jr, James Samuel; Baba, Justin S; Smith, M F

    2011-01-01

    Abstract- Motion-corrected awake animal imaging is needed for normal-state investigations of models of neurological disease and brain activity. The awake animal brain SPECT/CT system, AwakeSPECT at Johns Hopkins University has in the past used a single gamma camera for imaging. Enhancements have been made by adding a pinhole collimator to the second gamma camera at the opposite side which has been previously equipped parallel hole collimator. Geometry calibration was performed using a custom built quality control phantom containing three Co-57 point sources and applied to the tomographic reconstruction code. Hot-rod phantom scans with Tc-99m were performed to test sensitivity and resolution improvements. The reconstruction results show significant resolution and sensitivity improvements.

  9. Dual-headed SPECT for awake animal brain imaging

    SciTech Connect

    S. Lee, B. Kross, D. Weisenberger, J. McKisson, J.S. Goddard, J.S. Baba, M.S. Smith

    2012-02-01

    Motion-corrected awake animal imaging is needed for normal-state investigations of models of neurological disease and brain activity. The awake animal brain SPECT/CT system, AwakeSPECT at Johns Hopkins University has in the past used a single gamma camera for imaging. Enhancements have been made by adding a pinhole collimator to the second gamma camera at the opposite side which has been previously equipped parallel hole collimator. Geometry calibration was performed using a custom built quality control phantom containing three Co-57 point sources and applied to the tomographic reconstruction code. Hot-rod phantom scans with Tc-99m were performed to test sensitivity and resolution improvements. The reconstruction results show significant resolution and sensitivity improvements.

  10. [Brain SPECT in a case of Wernicke Korsakoff syndrome].

    PubMed

    Hervás-Benito, I; Pérez-Velasco, R

    In this article we report a 44 year old male with chronic alcoholism as antecedent and Wernicke Korsakoff s syndrome, studied with brain CT, MR and SPECT. In this work we review the different conclusion obtained with different studies and in different stages of the chronic alcoholism disease. Although several authors have described impaired frontal blood flow in the Wernicke Korsakoff s syndrome, in our case the parietal, temporal and occipital cortex were the most affected.

  11. Comparison of heterogeneity quantification algorithms for brain SPECT perfusion images

    PubMed Central

    2012-01-01

    Background Several algorithms from the literature were compared with the original random walk (RW) algorithm for brain perfusion heterogeneity quantification purposes. Algorithms are compared on a set of 210 brain single photon emission computed tomography (SPECT) simulations and 40 patient exams. Methods Five algorithms were tested on numerical phantoms. The numerical anthropomorphic Zubal head phantom was used to generate 42 (6 × 7) different brain SPECT simulations. Seven diffuse cortical heterogeneity levels were simulated with an adjustable Gaussian noise function and six focal perfusion defect levels with temporoparietal (TP) defects. The phantoms were successively projected and smoothed with Gaussian kernel with full width at half maximum (FWHM = 5 mm), and Poisson noise was added to the 64 projections. For each simulation, 5 Poisson noise realizations were performed yielding a total of 210 datasets. The SPECT images were reconstructed using filtered black projection (Hamming filter: α = 0.5). The five algorithms or measures tested were the following: the coefficient of variation, the entropy and local entropy, fractal dimension (FD) (box counting and Fourier power spectrum methods), the gray-level co-occurrence matrix (GLCM), and the new RW. The heterogeneity discrimination power was obtained with a linear regression for each algorithm. This regression line is a mean function of the measure of heterogeneity compared to the different diffuse heterogeneity and focal defect levels generated in the phantoms. A greater slope denotes a larger separation between the levels of diffuse heterogeneity. The five algorithms were computed using 40 99mTc-ethyl-cysteinate-dimer (ECD) SPECT images of patients referred for memory impairment. Scans were blindly ranked by two physicians according to the level of heterogeneity, and a consensus was obtained. The rankings obtained by the algorithms were compared with the physicians' consensus ranking. Results The GLCM method

  12. Comparison of heterogeneity quantification algorithms for brain SPECT perfusion images.

    PubMed

    Modzelewski, Romain; Janvresse, Elise; de la Rue, Thierry; Vera, Pierre

    2012-07-20

    Several algorithms from the literature were compared with the original random walk (RW) algorithm for brain perfusion heterogeneity quantification purposes. Algorithms are compared on a set of 210 brain single photon emission computed tomography (SPECT) simulations and 40 patient exams. Five algorithms were tested on numerical phantoms. The numerical anthropomorphic Zubal head phantom was used to generate 42 (6 × 7) different brain SPECT simulations. Seven diffuse cortical heterogeneity levels were simulated with an adjustable Gaussian noise function and six focal perfusion defect levels with temporoparietal (TP) defects. The phantoms were successively projected and smoothed with Gaussian kernel with full width at half maximum (FWHM = 5 mm), and Poisson noise was added to the 64 projections. For each simulation, 5 Poisson noise realizations were performed yielding a total of 210 datasets. The SPECT images were reconstructed using filtered black projection (Hamming filter: α = 0.5).The five algorithms or measures tested were the following: the coefficient of variation, the entropy and local entropy, fractal dimension (FD) (box counting and Fourier power spectrum methods), the gray-level co-occurrence matrix (GLCM), and the new RW.The heterogeneity discrimination power was obtained with a linear regression for each algorithm. This regression line is a mean function of the measure of heterogeneity compared to the different diffuse heterogeneity and focal defect levels generated in the phantoms. A greater slope denotes a larger separation between the levels of diffuse heterogeneity.The five algorithms were computed using 40 99mTc-ethyl-cysteinate-dimer (ECD) SPECT images of patients referred for memory impairment. Scans were blindly ranked by two physicians according to the level of heterogeneity, and a consensus was obtained. The rankings obtained by the algorithms were compared with the physicians' consensus ranking. The GLCM method (slope = 58.5), the fractal

  13. System Integration of FastSPECT III, a Dedicated SPECT Rodent-Brain Imager Based on BazookaSPECT Detector Technology

    PubMed Central

    Miller, Brian W.; Furenlid, Lars R.; Moore, Stephen K.; Barber, H. Bradford; Nagarkar, Vivek V.; Barrett, Harrison H.

    2010-01-01

    FastSPECT III is a stationary, single-photon emission computed tomography (SPECT) imager designed specifically for imaging and studying neurological pathologies in rodent brain, including Alzheimer’s and Parkinsons’s disease. Twenty independent BazookaSPECT [1] gamma-ray detectors acquire projections of a spherical field of view with pinholes selected for desired resolution and sensitivity. Each BazookaSPECT detector comprises a columnar CsI(Tl) scintillator, image-intensifier, optical lens, and fast-frame-rate CCD camera. Data stream back to processing computers via firewire interfaces, and heavy use of graphics processing units (GPUs) ensures that each frame of data is processed in real time to extract the images of individual gamma-ray events. Details of the system design, imaging aperture fabrication methods, and preliminary projection images are presented. PMID:21218137

  14. [Usefulness of SPECT images in helping radiologists understand brain diseases].

    PubMed

    Hayashida, K

    2001-04-01

    Nuclear brain imaging is able to show functional abnormalities of lesions that are not detectable by CT and MR images. The diagnostic keys of nuclear-imaging in terms of clinical usefulness are its early detection of lesions and determination of the efficacy of drug and surgical therapies. In dementic patients, F-18 FDG brain images can be diagnosed as Alzheimer's disease 12 months earlier than is possible on CT and MRI images, and can provide information for effective drug therapy. O-15 water CBF images can predict the effect of Nicholin by assessing transient increases in cerebral blood flow (CBF), thereby facilitating improvement in higher brain functions such as orientation. In stroke patients, brain SPECT images with Tc-99m HMPAO can predict fatal cerebral hemorrhage caused by anti-thrombic therapy by showing the decrease in count ratio (count ratio of infarcted to contralateral area of < 0.34) in the acute phase and identifying disruption of the blood brain barrier by showing hyperfixation in the subacute phase. Brain SPECT with I-123 IMP can also identify "misery" perfused areas resulting from reduced CBF and decreased vasoreactivity in the chronic phase. This criterion is utilized for patient selection for extracranial/intracranial bypass surgery, because patients with areas of poor perfusion might be indicated for such surgery. Since nuclear medicine images can accurately select candidates for drug or surgical therapies, they will be beneficial in reducing Medicare costs as well as in enhancing patients' quality of life as a result of the successful treatment. With the advancement of technology, nuclear medicine units that can simultaneously obtain CT images and can combine functional with anatomical images will provide more useful information for the diagnosis of brain disease.

  15. Robin Hood caught in Wonderland: brain SPECT findings.

    PubMed

    Morland, David; Wolff, Valérie; Dietemann, Jean-Louis; Marescaux, Christian; Namer, Izzie Jacques

    2013-12-01

    We present the case of a 53-year-old woman presenting several episodes of body image distortions, ground deformation illusions, and problems assessing distance in the orthostatic position corresponding to the Alice in Wonderland syndrome. No symptoms were reported when sitting or lying down. She had uncontrolled hypertension, hyperglycemia, hypercholesterolemia, and a history of head trauma. Her condition had been diagnosed with left internal carotid artery dissection 2 years earlier. Brain SPECT with 99mTc-ECD performed after i.v. injection of the radiotracer in supine and in standing positions showed hypoperfusion in the healthy contralateral frontoparietal operculum (Robin Hood syndrome), deteriorating when standing up.

  16. Multipinhole collimator with 20 apertures for a brain SPECT application

    SciTech Connect

    Lee, Tzu-Cheng; Ellin, Justin R.; Shrestha, Uttam; Seo, Youngho; Huang, Qiu; Gullberg, Grant T.

    2014-11-01

    Purpose: Several new technologies for single photon emission computed tomography (SPECT) instrumentation with parallel-hole collimation have been proposed to improve detector sensitivity and signal collection efficiency. Benefits from improved signal efficiency include shorter acquisition times and lower dose requirements. In this paper, the authors show a possibility of over an order of magnitude enhancement in photon detection efficiency (from 7.6 × 10{sup −5} to 1.6 × 10{sup −3}) for dopamine transporter (DaT) imaging of the striatum over the conventional SPECT parallel-hole collimators by use of custom-designed 20 multipinhole (20-MPH) collimators with apertures of 0.75 cm diameter. Methods: Quantifying specific binding ratio (SBR) of {sup 123}I-ioflupane or {sup 123}I-iometopane’s signal at the striatal region is a common brain imaging method to confirm the diagnosis of the Parkinson’s disease. The authors performed imaging of a striatal phantom filled with aqueous solution of I-123 and compared camera recovery ratios of SBR acquired between low-energy high-resolution (LEHR) parallel-hole collimators and 20-MPH collimators. Results: With only two-thirds of total acquisition time (20 min against 30 min), a comparable camera recovery ratio of SBR was achieved using 20-MPH collimators in comparison to that from the LEHR collimator study. Conclusions: Their systematic analyses showed that the 20-MPH collimator could be a promising alternative for the DaT SPECT imaging for brain over the traditional LEHR collimator, which could give both shorter scan time and improved diagnostic accuracy.

  17. Brain SPECT findings of anosognosia in Alzheimer's disease.

    PubMed

    Sedaghat, Fereshteh; Dedousi, Eleni; Baloyannis, Ioannis; Tegos, Thomas; Costa, Vasiliki; Dimitriadis, Athanasios S; Baloyannis, Stavros J

    2010-01-01

    Anosognosia is a common symptom of dementia. The aim of this study was to evaluate the contribution of different regions of the brain to anosognosia in Alzheimer's disease (AD) brains using single photon emission computed tomography (SPECT). Forty-two patients with AD were included in this study. After clinical interviews with the patients and their relatives, the patients were divided into two groups: Anosognosia and No-anosognosia. The patients were studied regarding the severity of dementia. They underwent SPECT with HMPAO and regional cerebral blood flow (rCBF) was measured. Regional CBF significantly differed between Anosognosia and No-anosognosia groups in right prefrontal (P < or = 0.02), right inferior parietal (P < or = 0.00), and right (P < or = 0.01) and left (P < or = 0.01) medial temporal cortex. There was a significant correlation between the severity of dementia and rCBF in medial temporal regions. When comparisons were made between mild and moderate stages separately, the 'right inferior parietal region' was the common region which showed hypoperfusion in both anosognosia subgroups. We conclude that anosognosia may be a reflection of functional impairment in right prefrontal, right frontal and especially right inferior parietal regions in AD.

  18. [Compartment analysis of 123I-IMP brain SPECT].

    PubMed

    Higano, S; Shishido, F; Aizawa, Y; Miura, S; Murakami, M; Inugami, A; Kanno, I; Fujita, H; Uemura, K

    1990-01-01

    To clarify the kinetics of N-isopropyl [123I]p-iodoamphetamine (IMP) in the brain, 2-compartment analysis was applied for brain SPECT with 57-minute dynamic scan in 9 subjects. The model consisted of blood component and brain tissue component. Two transfer rate constants were defined; k1 showed the rate from the blood to the brain tissue, and k2 was that of back diffusion. The late scan was performed 210 minutes after the tracer injection. Suitable k values best fitting to the dynamic data were determined for all regions of interest. Predicted regional cerebral activity at 210 minutes using 57-minute dynamic data was well agreed with measured activity. These showed the kinetics of IMP in the brain was well described by the 2-compartment model. The partition coefficient (k1/k2 ratio) was as large as about 35, and almost constant in the various brain structures including hypoperfused areas. These findings indicated that the initial IMP images reflected the reasonable CBF distribution, which gave relatively reliable CBF values even if using microsphere model.

  19. 99mTc-HMPAO perfusion SPECT/CT in the diagnosis of brain death.

    PubMed

    Derlin, Thorsten; Weiberg, Desiree

    2016-01-01

    This report describes a case of brain death (BD) evaluated by 99mTc-hexamethylpropylene amine oxime (HMPAO) single photon emission tomography/computed tomography (SPECT/CT). A 16-year-old boy with a history of rapid unexpected brain herniation due to pilocytic astrocytoma underwent 99mTc-HMPAO SPECT/CT for evaluation of brain death in the context of organ donation. Flow images demonstrated lack of blood flow to the brain, and delayed images showed absence of demonstrable radionuclide activity within the brain. SPECT/CT confirmed absence of tracer accumulation, and was deemed helpful for evaluation of the brain stem. 99mTc-HMPAO SPECT/CT is a valuable tool enabling imaging-based confirmation of BD.

  20. Compensation for non-uniform attenuation in SPECT brain imaging

    SciTech Connect

    Glick, S.J.; King, M.A.; Pan, T.S.

    1994-05-01

    Photon attenuation is a major limitation in performing quantitative SPECT brain imaging. A number of methods have been proposed for compensation of attenuation in regions of the body that can be modelled as a uniform attenuator. The magnitude of the errors introduced into reconstructed brain images by assuming the head to be a uniform attenuator are uncertain (the skull, sinus cavities and head holder all have different attenuation properties than brain tissue). Brain imaging is unique in that the radioisotope, for the most part, is taken up within a uniform attenuation medium (i.e., brain tissue) which is surrounded by bone (i.e., the skull) of a different density. Using this observation, Bellini`s method for attenuation compensation (which is an exact solution to the exponential Radon transform) has been modified to account for the different attenuation properties of the skull. To test this modified Bellini method, a simple mathematical phantom was designed to model the brain and a skull of varying thickness less than 7.5 mm. To model brain imaging with Tc-99m HMPAO, the attenuation coefficient of the brain tissue and skull were set to 0.15 cm{sup -1} and 0.22 cm{sup -1} respectively. A ray-driven projector which accounted for non-uniform attenuation was used to simulate projection data from 128 views. The detector response and scatter were not simulated. It was observed that reconstructions processed with uniform attenuation compensation (i.e., where it was assumed that the brain tissue and the skull had the same attenuation coefficient) provided errors of 6-20%, whereas those processed with the non-uniform Bellini algorithm were biased by only 0-5%.

  1. Automated coregistration and statistical analyses of SPECT brain images

    SciTech Connect

    Gong, W.; Devous, M.D.

    1994-05-01

    Statistical analyses of SPECT image data often require highly accurate image coregistration. Several image coregistration algorithms have been developed. The Pellizari algorithm (PA) uses the Powell technique to estimate transformation parameters between the {open_quotes}head{close_quotes} (model) and {open_quotes}hat{close_quotes} (images to be registered). Image normalization and good initial transformation parameters heavily affect the accuracy and speed of convergence of the PA. We have explored various normalization methods and found a simple technique that avoids most artificial edge effects and minimizes blurring of useful edges. We have tested the effects on accuracy and convergence speed of the PA caused by different initial transformation parameters. From these data, a modified PA was integrated into an automated coregistration system for SPECT brain images on the PRISM 3000S under X Windows. The system yields an accuracy of approximately 2 mm between model and registered images, and employs minimal user intervention through a simple graphic user interface. Data are automatically resliced, normalized and coregistered, with the user choosing only the slice range for inclusion and two initial transformation parameters (under computer-aided guidance). Coregistration is accomplished (converges) in approximately 8 min for a 128 x 128 x 128 set of 2 mm{sup 3} voxels. The complete process (editing, reslicing, normalization, coregistration) takes about 20 min. We have also developed automated 3-dimensional parametric images ({open_quotes}t{close_quotes}, {open_quotes}z{close_quotes}, and subtraction images) from coregistered data sets for statistical analyses. Data are compared against a coregistered normal control group (N = 50) distributed in age and gender for matching against subject samples.

  2. GATE simulation of a new design of pinhole SPECT system for small animal brain imaging

    NASA Astrophysics Data System (ADS)

    Uzun Ozsahin, D.; Bläckberg, L.; El Fakhri, G.; Sabet, H.

    2017-01-01

    Small animal SPECT imaging has gained an increased interest over the past decade since it is an excellent tool for developing new drugs and tracers. Therefore, there is a huge effort on the development of cost-effective SPECT detectors with high capabilities. The aim of this study is to simulate the performance characteristics of new designs for a cost effective, stationary SPECT system dedicated to small animal imaging with a focus on mice brain. The conceptual design of this SPECT system platform, Stationary Small Animal SSA-SPECT, is to use many pixelated CsI:TI detector modules with 0.4 mm × 0.4 mm pixels in order to achieve excellent intrinsic detector resolution where each module is backed by a single pinhole collimator with 0.3 mm hole diameter. In this work, we present the simulation results of four variations of the SSA-SPECT platform where the number of detector modules and FOV size is varied while keeping the detector size and collimator hole size constant. Using the NEMA NU-4 protocol, we performed spatial resolution, sensitivity, image quality simulations followed by a Derenzo-like phantom evaluation. The results suggest that all four SSA-SPECT systems can provide better than 0.063% system sensitivity and < 1.5 mm FWHM spatial resolution without resolution recovery or other correction techniques. Specifically, SSA-SPECT-1 showed a system sensitivity of 0.09% in combination with 1.1 mm FWHM spatial resolution.

  3. A methodology for generating normal and pathological brain perfusion SPECT images for evaluation of MRI/SPECT fusion methods: application in epilepsy

    NASA Astrophysics Data System (ADS)

    Grova, C.; Jannin, P.; Biraben, A.; Buvat, I.; Benali, H.; Bernard, A. M.; Scarabin, J. M.; Gibaud, B.

    2003-12-01

    Quantitative evaluation of brain MRI/SPECT fusion methods for normal and in particular pathological datasets is difficult, due to the frequent lack of relevant ground truth. We propose a methodology to generate MRI and SPECT datasets dedicated to the evaluation of MRI/SPECT fusion methods and illustrate the method when dealing with ictal SPECT. The method consists in generating normal or pathological SPECT data perfectly aligned with a high-resolution 3D T1-weighted MRI using realistic Monte Carlo simulations that closely reproduce the response of a SPECT imaging system. Anatomical input data for the SPECT simulations are obtained from this 3D T1-weighted MRI, while functional input data result from an inter-individual analysis of anatomically standardized SPECT data. The method makes it possible to control the 'brain perfusion' function by proposing a theoretical model of brain perfusion from measurements performed on real SPECT images. Our method provides an absolute gold standard for assessing MRI/SPECT registration method accuracy since, by construction, the SPECT data are perfectly registered with the MRI data. The proposed methodology has been applied to create a theoretical model of normal brain perfusion and ictal brain perfusion characteristic of mesial temporal lobe epilepsy. To approach realistic and unbiased perfusion models, real SPECT data were corrected for uniform attenuation, scatter and partial volume effect. An anatomic standardization was used to account for anatomic variability between subjects. Realistic simulations of normal and ictal SPECT deduced from these perfusion models are presented. The comparison of real and simulated SPECT images showed relative differences in regional activity concentration of less than 20% in most anatomical structures, for both normal and ictal data, suggesting realistic models of perfusion distributions for evaluation purposes. Inter-hemispheric asymmetry coefficients measured on simulated data were found within

  4. A methodology for generating normal and pathological brain perfusion SPECT images for evaluation of MRI/SPECT fusion methods: application in epilepsy.

    PubMed

    Grova, C; Jannin, P; Biraben, A; Buvat, I; Benali, H; Bernard, A M; Scarabin, J M; Gibaud, B

    2003-12-21

    Quantitative evaluation of brain MRI/SPECT fusion methods for normal and in particular pathological datasets is difficult, due to the frequent lack of relevant ground truth. We propose a methodology to generate MRI and SPECT datasets dedicated to the evaluation of MRI/SPECT fusion methods and illustrate the method when dealing with ictal SPECT. The method consists in generating normal or pathological SPECT data perfectly aligned with a high-resolution 3D T1-weighted MRI using realistic Monte Carlo simulations that closely reproduce the response of a SPECT imaging system. Anatomical input data for the SPECT simulations are obtained from this 3D T1-weighted MRI, while functional input data result from an inter-individual analysis of anatomically standardized SPECT data. The method makes it possible to control the 'brain perfusion' function by proposing a theoretical model of brain perfusion from measurements performed on real SPECT images. Our method provides an absolute gold standard for assessing MRI/SPECT registration method accuracy since, by construction, the SPECT data are perfectly registered with the MRI data. The proposed methodology has been applied to create a theoretical model of normal brain perfusion and ictal brain perfusion characteristic of mesial temporal lobe epilepsy. To approach realistic and unbiased perfusion models, real SPECT data were corrected for uniform attenuation, scatter and partial volume effect. An anatomic standardization was used to account for anatomic variability between subjects. Realistic simulations of normal and ictal SPECT deduced from these perfusion models are presented. The comparison of real and simulated SPECT images showed relative differences in regional activity concentration of less than 20% in most anatomical structures, for both normal and ictal data, suggesting realistic models of perfusion distributions for evaluation purposes. Inter-hemispheric asymmetry coefficients measured on simulated data were found within

  5. [Value of thallium 201-SPECT in typing brain space-occupying lesions].

    PubMed

    Martínez del Valle Torres, M D; Gómez Rio, M; Rodríguez Fernández, A; Sabatel Hernandez, G; Ortega Lozano, S; Ramos Font, C; Bellon Guardia, M; López Ramírez, E; Llamas Elvira, J M

    2004-01-01

    This study was designed to assess the diagnostic accuracy of single photon emission computed tomography with Tl-201 (SPECT Tl-201) to establish the tumoral or non-tumoral nature of brain space occupying lesions in comparison with usual diagnostic techniques. The study population consisted of 37 patients, 24 men (64.9 %) and 13 women (35.1 %), mean age 48 +/- 16 years. After establishing the clinical and radiological diagnosis of brain lesion, all patients underwent SPECT Tl-201, evaluating it only by subjective analysis and blinded to neuroestructural techniques. After surgical resection all patients were evaluated anatomopathologically to establish the histologic nature. The sensitivity of SPECT Tl-201 (0.87) was higher than standard neuroimaging techniques (0.78). Specificity (0.43), positive (0.87) and negative (0.43) predictive values of SPECT were similar to neuroestructural procedures (MRI and CT scan) with 0.43, 0.82 and 0.38 values. Tumoral disease prevalence was 0.81. Neuroestructural procedures were non-conclusive in 18.9 % of the studies. No non-conclusive results were obtained with SPECT Tl-201. SPECT Tl-201 is a diagnostic procedure of high sensitivity to establish the tumoral nature of brain lesions, with poor specificity, similar to structural X-ray techniques.

  6. Discrepancies in brain perfusion SPECT findings between Tc-99m HMPAO and Tc-99m ECD: evaluation using dynamic SPECT in patients with hyperemia.

    PubMed

    Miyazawa, N; Koizumi, K; Mitsuka, S; Nukui, H

    1998-10-01

    Discrepancies have been reported between the findings of Tc-99m HMPAO and Tc-99m ECD brain perfusion SPECT imaging. This study investigated the discrepancies in the accumulation of these tracers using dynamic SPECT to detect the super early phase of distribution. Thirteen patients with luxury perfusion or high flow states were studied with both dynamic and standard SPECT using Tc-99m HMPAO and Tc-99m ECD within 1-3 days. Standard SPECT showed discrepancies in 6 of 13 patients. Patients with meningioma and cerebral thrombosis had increased accumulation of Tc-99m HMPAO and decreased uptake of Tc-99m ECD. Patients with arteriovenous malformation, subarachnoid hemorrhage, and cavernous angioma had decreased accumulation of both tracers, but to different degrees. Dynamic SPECT showed increased or normal accumulation (i.e., essentially no discrepancy) in the first few minutes. However, Tc-99m HMPAO had a longer retention time than Tc-99m ECD in the ensuing 5-10 minutes. Dynamic SPECT revealed a similar accumulation pattern but different washout rates for the two tracers. Tc-99m HMPAO might be a more suitable tracer to detect high flow states or luxury perfusion because the findings on standard SPECT were more in agreement with those of dynamic SPECT using this tracer.

  7. 5-HT Radioligands for Human Brain Imaging With PET and SPECT

    PubMed Central

    Paterson, Louise M.; Kornum, Birgitte R.; Nutt, David J.; Pike, Victor W.; Knudsen, Gitte M.

    2014-01-01

    The serotonergic system plays a key modulatory role in the brain and is the target for many drug treatments for brain disorders either through reuptake blockade or via interactions at the 14 subtypes of 5-HT receptors. This review provides the history and current status of radioligands used for positron emission tomography (PET) and single photon emission computerized tomography (SPECT) imaging of human brain serotonin (5-HT) receptors, the 5-HT transporter (SERT), and 5-HT synthesis rate. Currently available radioligands for in vivo brain imaging of the 5-HT system in humans include antagonists for the 5-HT1A, 5-HT1B, 5-HT2A, and 5-HT4 receptors, and for SERT. Here we describe the evolution of these radioligands, along with the attempts made to develop radioligands for additional serotonergic targets. We describe the properties needed for a radioligand to become successful and the main caveats. The success of a PET or SPECT radioligand can ultimately be assessed by its frequency of use, its utility in humans, and the number of research sites using it relative to its invention date, and so these aspects are also covered. In conclusion, the development of PET and SPECT radioligands to image serotonergic targets is of high interest, and successful evaluation in humans is leading to invaluable insight into normal and abnormal brain function, emphasizing the need for continued development of both SPECT and PET radioligands for human brain imaging. PMID:21674551

  8. Registration and display of brain SPECT and MRI using external markers.

    PubMed

    Pohjonen, H; Nikkinen, P; Sipilä, O; Launes, J; Salli, E; Salonen, O; Karp, P; Ylä-Jääski, J; Katila, T; Liewendahl, K

    1996-02-01

    Accurate anatomical localisation of abnormalities observed in brain perfusion single-photon emission computed tomography (SPECT) is difficult, but can be improved by correlating data from SPECT and other tomographic imaging modalities. For this purpose we have developed software to register, analyse and display 99mTc-hexamethylpropyleneamine oxime SPECT and 1.0 T MRI of the brain. For registration of SPECT and MRI data external skin markers containing 99mTc (220 kBq) in 50 microliters of coconut butter were used. The software is coded in the C programming language, and the X Window system and the OSF/Motif standards are used for graphics and definition of the user interface. The registration algorithm follows a noniterative least-squares method using singular value decomposition of a 3 x 3 covariance matrix. After registration, the image slices of both data sets are shown at identical tomographic levels. The registration error in phantom studies was on average 4 mm. In the two-dimensional display mode the orthogonal cross-sections of the data sets are displayed side by side. In the three-dimensional mode MRI data are displayed as a surface-shaded 3 D reconstruction and SPECT data as cut planes. The usefulness of this method is demonstrated in patients with cerebral infarcts, brain tumour, herpes simplex encephalitis and epilepsy.

  9. SPECT study of low intensity He-Ne laser intravascular irradiation therapy for brain infarction

    NASA Astrophysics Data System (ADS)

    Xiao, Xue-Chang; Dong, Jia-Zheng; Chu, Xiao-Fan; Jia, Shao-Wei; Liu, Timon C.; Jiao, Jian-Ling; Zheng, Xi-Yuan; Zhou, Ci-Xiong

    2003-12-01

    We used single photon emission computed tomography (SPECT) in brain perfusion imaging to study the changes of regional cerebral blood flow (rCBF) and cerebral function in brain infarction patients treated with intravascular laser irradiation of blood (ILIB). 17 of 35 patients with brain infarction were admitted to be treated by ILIB on the base of standard drug therapy, and SPECT brain perfusion imaging was performed before and after ILIB therapy with self-comparison. The results were analyzed in quantity with brain blood flow function change rate (BFCR%) model. Effect of ILIB during the therapy process in the other 18 patients were also observed. In the 18 patients, SPECT indicated an improvement of rCBF (both in focus and in total brain) and cerebral function after a 30 min-ILIB therapy. And the 17 patients showed an enhancement of total brain rCBF and cerebral function after ILIB therapy in comparison with that before, especially for the focus side of the brain. The enhancement for focus itself was extremely obvious with a higher significant difference (P<0.0001). The mirror regions had no significant change (P>0.05). BFCR% of foci was prominently higher than that of mirror regions (P<0.0001). In conclusion, the ILIB therapy can improve rCBF and cerebral function and activate brain cells of patients with brain infarction. The results denote new evidence of ILIB therapy for those patients with cerebral ischemia.

  10. Automated three-dimensional quantification of myocardial perfusion and brain SPECT.

    PubMed

    Slomka, P J; Radau, P; Hurwitz, G A; Dey, D

    2001-01-01

    To allow automated and objective reading of nuclear medicine tomography, we have developed a set of tools for clinical analysis of myocardial perfusion tomography (PERFIT) and Brain SPECT/PET (BRASS). We exploit algorithms for image registration and use three-dimensional (3D) "normal models" for individual patient comparisons to composite datasets on a "voxel-by-voxel basis" in order to automatically determine the statistically significant abnormalities. A multistage, 3D iterative inter-subject registration of patient images to normal templates is applied, including automated masking of the external activity before final fit. In separate projects, the software has been applied to the analysis of myocardial perfusion SPECT, as well as brain SPECT and PET data. Automatic reading was consistent with visual analysis; it can be applied to the whole spectrum of clinical images, and aid physicians in the daily interpretation of tomographic nuclear medicine images.

  11. Cerebral abnormalities in cocaine abusers: Demonstration by SPECT perfusion brain scintigraphy. Work in progress

    SciTech Connect

    Tumeh, S.S.; Nagel, J.S.; English, R.J.; Moore, M.; Holman, B.L. )

    1990-09-01

    Single photon emission computed tomography (SPECT) perfusion brain scans with iodine-123 isopropyl iodoamphetamine (IMP) were obtained in 12 subjects who acknowledged using cocaine on a sporadic to a daily basis. The route of cocaine administration varied from nasal to intravenous. Concurrent abuse of other drugs was also reported. None of the patients were positive for human immunodeficiency virus. Brain scans demonstrated focal defects in 11 subjects, including seven who were asymptomatic, and no abnormality in one. Among the findings were scattered focal cortical deficits, which were seen in several patients and which ranged in severity from small and few to multiple and large, with a special predilection for the frontal and temporal lobes. No perfusion deficits were seen on I-123 SPECT images in five healthy volunteers. Focal alterations in cerebral perfusion are seen commonly in asymptomatic drug users, and these focal deficits are readily depicted by I-123 IMP SPECT.

  12. Quantitative analysis of L-SPECT system for small animal brain imaging

    NASA Astrophysics Data System (ADS)

    Rahman, Tasneem; Tahtali, Murat; Pickering, Mark R.

    2016-03-01

    This paper aims to investigate the performance of a newly proposed L-SPECT system for small animal brain imaging. The L-SPECT system consists of an array of 100 × 100 micro range diameter pinholes. The proposed detector module has a 48 mm by 48 mm active area and the system is based on a pixelated array of NaI crystals (10×10×10 mm elements) coupled with an array of position sensitive photomultiplier tubes (PSPMTs). The performance of this system was evaluated with pinhole radii of 50 μm, 60 μm and 100 μm. Monte Carlo simulation studies using the Geant4 Application for Tomographic Emission (GATE) software package validate the performance of this novel dual head L-SPECT system where a geometric mouse phantom is used to investigate its performance. All SPECT data were obtained using 120 projection views from 0° to 360° with a 3° step. Slices were reconstructed using conventional filtered back projection (FBP) algorithm. We have evaluated the quality of the images in terms of spatial resolution (FWHM) based on line spread function, the system sensitivity, the point source response function and the image quality. The sensitivity of our newly proposed L- SPECT system was about 4500 cps/μCi at 6 cm along with excellent full width at half-maximum (FWHM) using 50 μm pinhole aperture at several radii of rotation. The analysis results show the combination of excellent spatial resolution and high detection efficiency over an energy range between 20-160 keV. The results demonstrate that SPECT imaging using a pixelated L-SPECT detector module is applicable in a quantitative study of mouse brain imaging.

  13. Brain-stem Listeriosis: A Comparison of SPECT and MRI Findings

    PubMed Central

    Sahin, Sevki; Arisoy, Ayse S.; Topkaya, Aynur E.; Karsidag, Sibel

    2006-01-01

    Abstract and Introduction Abstract Listeria monocytogenes, although uncommon as a cause of illness in the general population, can result in serious illness when it affects pregnant women, neonates, the elderly, and immunocompromised individuals. Typically, it is a food-borne organism. This report describes a case of brain-stem listeriosis in a previously healthy 51-year-old woman. The diagnosis was based on clinical findings, the results of cerebrospinal fluid (CSF) analysis, CSF culture, and magnetic resonance imaging (MRI) findings. MRI demonstrated upper brain stem and cerebellar peduncle involvement. In addition, Tc-99m exametazime (HMPAO)-labeled single photon emission computed tomography (SPECT) of the brain revealed bilateral cerebellar hypoperfusion. Antibiotic therapy resulted in partial clinical recovery after 3 weeks. At the end of 6 months, brain-stem findings had nearly resolved. However, although minimal residual findings were observed on MRI at 6 months, bilateral diffuse cerebellar hypoperfusion remained on Tc-99m HMPAO brain SPECT. PMID:17415328

  14. Brain SPECT can differentiate between essential tremor and early-stage tremor-dominant Parkinson's disease.

    PubMed

    Song, In-Uk; Park, Jeong-Wook; Chung, Sung-Woo; Chung, Yong-An

    2014-09-01

    There are no confirmatory or diagnostic tests or tools to differentiate between essential tremor (ET) and tremor in idiopathic Parkinson's disease (PD). Although a number of imaging studies have indicated that there are differences between ET and PD, the functional imaging study findings are controversial. Therefore, we analyzed regional cerebral blood flow (CBF) by perfusion brain single-photon emission computed tomography (SPECT) to identify differences between ET and tremor-dominant Parkinson's disease (TPD). We recruited 33 patients with TPD, 16 patients with ET, and 33 healthy controls. We compared the severity of tremor symptoms by comparing the Fahn-Tolosa-Marin rating scale (FTM) score and the tremor score from Unified Parkinson's Disease Rating Scale (UPDRS) between TPD and ET patients. Subjects were evaluated by neuropsychological assessments, MRI and perfusion SPECT of the brain. Total FTM score was significantly higher in ET patients than TPD patients. However, there was no significant difference in FTM Part A scores between the two patient groups, while the scores for FTM Part B and C were significantly higher in ET patients than TPD patients. Brain SPECT analysis of the TPD group demonstrated significant hypoperfusion of both the lentiform nucleus and thalamus compared to the ET group. Brain perfusion SPECT may be a useful clinical method to differentiate between TPD and ET even during early-phase PD, because the lentiform nucleus and thalamus show differences in regional perfusion between these two groups during this time period. Additionally, we found evidence of cerebellar dysfunction in both TPT and ET.

  15. Voxel-by-voxel analysis of brain SPECT perfusion in Fibromyalgia

    NASA Astrophysics Data System (ADS)

    Guedj, Eric; Taïeb, David; Cammilleri, Serge; Lussato, David; de Laforte, Catherine; Niboyet, Jean; Mundler, Olivier

    2007-02-01

    We evaluated brain perfusion SPECT at rest, without noxious stiumuli, in a homogeneous group of hyperalgesic FM patients. We performed a voxel-based analysis in comparison to a control group, matched for age and gender. Under such conditions, we made the assumption that significant cerebral perfusion abnormalities could be demonstrated, evidencing altered cerebral processing associated with spontaneous pain in FM patients. The secondary objective was to study the reversibility and the prognostic value of such possible perfusion abnormalities under specific treatment. Eighteen hyperalgesic FM women (mean age 48 yr; range 25-63 yr; ACR criteria) and 10 healthy women matched for age were enrolled in the study. A voxel-by-voxel group analysis was performed using SPM2 ( p<0.05, corrected for multiple comparisons). All brain SPECT were performed before any change was made in therapy in the pain care unit. A second SPECT was performed a month later after specific treatment by Ketamine. Compared to control subjects, we observed individual brain SPECT abnormalities in FM patients, confirmed by SPM2 analysis with hyperperfusion of the somatosensory cortex and hypoperfusion of the frontal, cingulate, medial temporal and cerebellar cortices. We also found that a medial frontal and anterior cingulate hypoperfusions were highly predictive (PPV=83%; NPV=91%) of non-response on Ketamine, and that only responders showed significant modification of brain perfusion, after treatment. In the present study performed without noxious stimuli in hyperalgesic FM patients, we found significant hyperperfusion in regions of the brain known to be involved in sensory dimension of pain processing and significant hypoperfusion in areas assumed to be associated with the affective dimension. As current pharmacological and non-pharmacological therapies act differently on both components of pain, we hypothesize that SPECT could be a valuable and readily available tool to guide individual therapeutic

  16. Brain SPECT imaging within the Talairach reference system: a simple registration algorithm

    NASA Astrophysics Data System (ADS)

    Meunier, Jean; Imbert, Bernard; Janicki, Christian; Soucy, Jean-Paul

    1998-06-01

    An important goal to achieve in order to improve the clinical usefulness of regional cerebral blood flow (rCBF) SPECT studies is to register each brain to a standard anatomical atlas. For this purpose, we propose a simple three steps method. First the mid-sagittal plane is computed based on the left-right symmetry of the brain. Then the AC- PC line (main axis of the Talairach & Tournoux reference system) is obtained from the positions of four landmarks in the mid-sagittal plane. Finally, three linear scaling parameters are determined to adjust the size of the subject brain within the Talairach & Tournoux Atlas. The method was successfully validated with a set of 64 X 64 X 64 SPECT Monte-Carlo simulations of the brain.

  17. Blind deconvolution of human brain SPECT images using a distribution mixture estimation

    NASA Astrophysics Data System (ADS)

    Mignotte, Max; Meunier, Jean

    2000-06-01

    Thanks to its ability to yield functionally-based information, the SPECT imagery technique has become a great help in the diagnostic of cerebrovascular diseases. Nevertheless, due to the imaging process, SPECT images are blurred and consequently their interpretation by the clinician is often difficult. In order to improve the spatial resolution of these images and then to facilitate their interpretation, we propose herein to implement a deconvolution procedure relying on an accurate distribution mixture parameter estimation procedure. Parameters of this distribution mixture are efficiently exploited in order to prevent overfitting of the noisy data or to determine the support of the object to be deconvolved when this one is needed. In this context, we compare the deconvolution results obtained by the Lucy-Richardson method and by the recent blind deconvolution technique called the NAS-RIF algorithm on real and simulated brain SPECT images. The NAS-RIF performs the best and shows significant contrast enhancement with little mottle (noise) amplification.

  18. Pattern of brain blood perfusion in tinnitus patients using technetium-99m SPECT imaging

    PubMed Central

    Mahmoudian, Saeid; Farhadi, Mohammad; Gholami, Saeid; Saddadi, Fariba; Karimian, Ali Reza; Mirzaei, Mohammad; Ghoreyshi, Esmaeel; Ahmadizadeh, Majid; Lenarz, Thomas

    2012-01-01

    Background and Purpose: Tinnitus is associated with an increased activity in central auditory system as demonstrated by neuroimaging studies. Brain perfusion scanning using single photon emission computed tomography (SPECT) was done to understand the pattern of brain blood perfusion of tinnitus subjects and find the areas which are mostly abnormal in these patients. Materials and Methods: A number of 122 patients with tinnitus were enrolled to this cross-sectional study. They underwent SPECT and magnetic resonance imaging (MRI) of brain, and the images were fused to find the regions with abnormal perfusion. Results: SPECT scan results were abnormal in 101 patients (83%). Most patients had bilateral abnormal perfusion (N = 65, 53.3%), and most subjects had abnormality in middle-temporal gyrus (N = 83, 68%) and temporoparietal cortex (N = 46, 37.7%). Patients with multifocal involvement had the least mean age than other 2 groups (patients with no abnormality and unifocal abnormality) (P value = 0.045). Conclusions: Brain blood perfusion pattern differs in patient with tinnitus than others. These patients have brain perfusion abnormality, mostly in auditory gyrus (middle temporal) and associative cortex (temporoparietal cortex). Multifocal abnormalities might be due to more cognitive and emotional brain centers involvement due to tinnitus or more stress and anxiety of tinnitus in the young patients. PMID:23267375

  19. Perfusion brain SPECT in assessing motor improvement after deep brain stimulation in Parkinson's disease.

    PubMed

    Paschali, Anna; Constantoyannis, Constantinos; Angelatou, Fevronia; Vassilakos, Pavlos

    2013-03-01

    High-frequency deep brain stimulation (DBS) of the subthalamic nucleus (STN) has become an established therapeutic approach for the management of patients with late-stage idiopathic Parkinson's disease (PD). The aim of the present study was to assess regional cerebral blood flow (rCBF) changes related to motor improvement. Twenty-one PD patients underwent two rCBF SPECT studies at rest, once preoperatively in the off-meds state and the other postoperatively (at 6 ± 2 months) in the off medication/on stimulation state. Patients were classified according to the UPDRS and H&Y scale. NeuroGam software was used to register, quantify, and compare two sequential brain SPECT studies of the same patient in order to investigate rCBF changes during STN stimulation in comparison with preoperative rCBF. The relationship between rCBF and UPDRS scores was used as a covariate of interest. Twenty patients showed clinical improvement during the first months after surgery, resulting in a 44 % reduction of the UPDRS motor score. The administered mean daily levodopa dose significantly decreased from 850 ± 108 mg before surgery to 446 ± 188 mg during the off-meds state (p < 0.001, paired t test). At the 6-month postoperative assessment, we noticed rCBF increases in the pre-supplementary motor area (pre-SMA) and the premotor cortex (PMC) (mean rCBF increase = 10.2 %, p < 0.05), the dorsolateral prefrontal cortex and in associative and limbic territories of the frontal cortex (mean rCBF increase = 8.2 %, p > 0.05). A correlation was detected between the improvement in motor scores and the rCBF increase in the pre-SMA and PMC (r = 0.89, p < 0.001). Our study suggests that STN stimulation leads to improvement in neural activity and rCBF increase in higher-order motor cortical areas.

  20. Validation of brain tumour imaging with p-[123I]iodo-L-phenylalanine and SPECT.

    PubMed

    Hellwig, Dirk; Ketter, Ralf; Romeike, Bernd F M; Sell, Nadja; Schaefer, Andrea; Moringlane, Jean R; Kirsch, Carl-Martin; Samnick, Samuel

    2005-09-01

    The aims of this prospective study were to validate single-photon emission computed tomography (SPECT) with p-[(123)I]iodo-L-phenylalanine (IPA) in brain tumours and to evaluate its potential for the characterisation of indeterminate brain lesions. In 45 patients with indeterminate brain lesions or suspected progression of glioma, amino acid uptake was studied using IPA-SPECT and compared with the final diagnosis established by biopsy or serial imaging. After image fusion of IPA-SPECT and magnetic resonance imaging, the presence of tumour was visually determined by two independent observers. IPA uptake was quantified as the ratio between maximum uptake in the suspicious lesion and mean uptake in unaffected brain. Primary brain tumours were present in 35 cases (12 low-grade and 23 high-grade gliomas). Non-neoplastic brain lesions were confirmed in seven cases (three dysplasias, three inflammatory lesions, one lesion after effective therapy). Visual analysis showed a high concordance between the two observers (kappa=0.90, p<0.001), with sensitivity and specificity of 86% and 100% for the discrimination of primary brain tumours and non-neoplastic lesions. At 30 min p.i., IPA uptake in primary brain tumours was higher than that in non-neoplastic lesions (1.70+/-0.36 vs 1.14+/-0.18, p<0.05). Brain metastases showed no increased uptake (1.13+/-0.22, n=3). The persistent retention of IPA in low-grade gliomas without disruption of the blood-brain barrier was visualised up to 24 h p.i. Low-grade and high-grade gliomas showed equivalent IPA uptake (1.72+/-0.37 vs 1.67+/-0.36 at 30 min, p=0.745). IPA shows long and specific retention in gliomas. IPA is a promising and safe radiopharmaceutical for the visualisation of gliomas and the characterisation of indeterminate brain lesions.

  1. Visual and semi-quantitative assessment of brain tumors using (201)Tl-SPECT.

    PubMed

    Nose, Ayumi; Otsuka, Hideki; Nose, Hayato; Otomi, Yoichi; Terazawa, Kaori; Harada, Masafumi

    2013-01-01

    To evaluate the usefulness of (201)Tl-SPECT in differentiating benign from malignant brain tumors. Eighty-eight patients (44 males and 44 females) with 58 high-grade (WHO grade III-IV) and 30 low-grade (WHO grade I-II) tumors were evaluated with (201)Tl-SPECT. (1) Visual assessment was performed by board-certificated radiologists using (201)Tl-SPECT. Tumors were classified in two groups (Tl-positive and Tl-negative) and scored using the five grade evaluation system. Receiver operating characteristic (ROC) analysis was performed in the Tl-positive group. (2) Semi-quantitative assessment involved measurement of early and delayed (201)Tl uptake, and the retention index (RI) was applied as follows: RI=delayed uptake ratio/early uptake ratio. Three combinations of RI using mean and maximum values of the region of interest were calculated. (1) Seventy-four Tl-positive and 14 Tl-negative tumors. The area under the ROC curve (AUC) estimated by three radiologists exceeded a value of 0.7. The value was greater when estimated by the more experienced radiologist. (2) In all RIs, the difference of RI between high-grade tumors and low-grade tumors was statistically significant. A visual and semi-quantitative assessment using (201)Tl-SPECT was found to be useful for differentiating benign from malignant brain tumors.

  2. Thallium SPECT-based stereotactic targeting for brain tumor biopsies. A technical note.

    PubMed

    Hemm, S; Vayssiere, Nathalie; Zanca, Michel; Ravel, Patrice; Coubes, Philippe

    2004-01-01

    MR or CT images acquired under stereotactic conditions are often used to plan and guide brain tumor biopsies. The objective of this study was to design and test a methodology to increase target selection reliability by acquiring stereotactic 201Tl-SPECT data and by integrating them into the surgical planning. The three-headed Philips gamma camera system (Prism 3000) was adapted to stereotactic acquisitions (patient pallet, headholder). A software was developed for the stereotactic target determination based on SPECT images (pixel with the highest metabolic activity inside the tumor). The whole system accuracy was tested with the Elekta phantom adapted to SPECT imaging. The methodology was applied to one brain tumor biopsy. Comparison of the specific phantom coordinates evaluated in SPECT with the theoretical ones did not reveal any significant difference. In this way, our methodology including our homemade software (identification of the stereotactic frame, determination of the pixel with highest metabolic activity within the tumor in the stereotactic coordinate system) was validated. No significant geometric deformations were detected. Clinical feasibility was confirmed in 1 patient with a brain glioma. This study illustrates the feasibility and the accuracy of SPECT acquisitions with the stereotactic Leksell G-frame. The clinical relevance of this methodology is under evaluation. This definition of the target, based on the point with the highest metabolic activity within the tumor, might lead to improved diagnosis in biopsies and patient management. Furthermore, it might prepare the future for therapy aimed at delivering a therapeutic agent within a tumor. Copyright 2004 S. Karger AG, Basel

  3. Brain perfusion SPECT in the mouse: normal pattern according to gender and age.

    PubMed

    Apostolova, Ivayla; Wunder, Andreas; Dirnagl, Ulrich; Michel, Roger; Stemmer, Nina; Lukas, Mathias; Derlin, Thorsten; Gregor-Mamoudou, Betina; Goldschmidt, Jürgen; Brenner, Winfried; Buchert, Ralph

    2012-12-01

    Regional cerebral blood flow (rCBF) is a useful surrogate marker of neuronal activity and a parameter of primary interest in the diagnosis of many diseases. The increasing use of mouse models spawns the demand for in vivo measurement of rCBF in the mouse. Small animal SPECT provides excellent spatial resolution at adequate sensitivity and is therefore a promising tool for imaging the mouse brain. This study evaluates the feasibility of mouse brain perfusion SPECT and assesses the regional pattern of normal Tc-99m-HMPAO uptake and the impact of age and gender. Whole-brain kinetics was compared between Tc-99m-HMPAO and Tc-99m-ECD using rapid dynamic planar scans in 10 mice. Assessment of the regional uptake pattern was restricted to the more suitable tracer, HMPAO. Two HMPAO SPECTs were performed in 18 juvenile mice aged 7.5 ± 1.5weeks, and in the same animals at young adulthood, 19.1 ± 4.0 weeks (nanoSPECT/CTplus, general purpose mouse apertures: 1.2kcps/MBq, 0.7mm FWHM). The 3-D MRI Digital Atlas Database of an adult C57BL/6J mouse brain was used for region-of-interest (ROI) analysis. SPECT images were stereotactically normalized using SPM8 and a custom made, left-right symmetric HMPAO template in atlas space. For testing lateral asymmetry, each SPECT was left-right flipped prior to stereotactical normalization. Flipped and unflipped SPECTs were compared by paired testing. Peak brain uptake was similar for ECD and HMPAO: 1.8 ± 0.2 and 2.1 ± 0.6 %ID (p=0.357). Washout after the peak was much faster for ECD than for HMPAO: 24 ± 7min vs. 4.6 ± 1.7h (p=0.001). The general linear model for repeated measures with gender as an intersubject factor revealed an increase in relative HMPAO uptake with age in the neocortex (p=0.018) and the hippocampus (p=0.012). A decrease was detected in the midbrain (p=0.025). Lateral asymmetry, with HMPAO uptake larger in the left hemisphere, was detected primarily in the neocortex, both at juvenile age (asymmetry index AI=2.7 ± 1

  4. Scatter and attenuation correction for brain SPECT using attenuation distributions inferred from a head atlas.

    PubMed

    Stodilka, R Z; Kemp, B J; Prato, F S; Kertesz, A; Kuhl, D; Nicholson, R L

    2000-09-01

    Sequential transmission scanning (TS)/SPECT is impractical for neurologically impaired patients who are unable to keep their heads motionless for the extended duration of the combined scans. To provide an alternative to TS, we have developed a method of inferring-attenuation distributions (IADs), from SPECT data, using a head atlas and a registration program. The validity of replacing TS with IAD was tested in 10 patients with mild dementia. TS was conducted with each patient using a collimated 99mTc line source and fanbeam collimator; this was followed by hexamethyl propyleneamine oxime-SPECT. IAD was derived by deformably registering the brain component of a digital head atlas to a preliminary SPECT reconstruction and then applying the resulting spatial transformation to the full head atlas. SPECT data were reconstructed with scatter and attenuation correction. Relative regional cerebral blood flow was quantified in 12 threshold-guided anatomic regions of interest, with cerebellar normalization. SPECT reconstructions using IAD were compared with those using TS (which is the "gold standard") in terms of these regions of interest. When we compared all regions of interest across the population, the correlation between IAD-guided and TS-guided SPECT scans was 0.92 (P < 0.0001), whereas the mean absolute difference between the scans was 7.5%. On average, IAD resulted in slight underestimation of relative regional cerebral blood flow; however, this underestimation was statistically significant for only the left frontal and left central sulcus regions (P = 0.001 and 0.002, respectively). Error analysis indicated that approximately 10.0% of the total error was caused by IAD scatter correction, 36.6% was caused by IAD attenuation correction, 27.0% was caused by discrepancies in region-of-interest demarcation from quantitative errors in IAD-guided reconstructions, and 26.5% was caused by patient motion throughout the imaging procedure. SPECT reconstructions guided by IAD

  5. Probabilistic multiobject deformable model for MR/SPECT brain image registration and segmentation

    NASA Astrophysics Data System (ADS)

    Nikou, Christophoros; Heitz, Fabrice; Armspach, Jean-Paul

    1999-05-01

    A probabilistic deformable model for the representation of brain structures is described. The statistically learned deformable model represents the relative location of head (skull and scalp) and brain surfaces in MR/SPECT images pairs and accommodates the significant variability of these anatomical structures across different individuals. To provide a training set, a representative collection of 3D MRI volumes of different patients have first been registered to a reference image. The head and brain surfaces of each volume are parameterized by the amplitudes of the vibration modes of a deformable spherical mesh. For a given MR image in the training set, a vector containing the largest vibration modes describing the head and the brain is created. This random vector is statistically constrained by retaining the most significant variations modes of its Karhunen-Loeve expansion on the training population. By these means, both head and brain surfaces are deformed according to the anatomical variability observed in the training set. Two applications of the probabilistic deformable model are presented: the deformable model-based registration of 3D multimodal (MR/SPECT) brain images and the segmentation of the brain from MRI using the probabilistic constraints embedded in the deformable model. The multi-object deformable model may be considered as a first step towards the development of a general purpose probabilistic anatomical atlas of the brain.

  6. Objective documentation of traumatic brain injury subsequent to mild head trauma: multimodal brain imaging with MEG, SPECT, and MRI.

    PubMed

    Lewine, Jeffrey David; Davis, John T; Bigler, Erin D; Thoma, Robert; Hill, Dina; Funke, Michael; Sloan, John Henry; Hall, Sandra; Orrison, William W

    2007-01-01

    To determine to what extent magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT), and magnetoencephalography (MEG) can provide objective evidence of brain injury in adult patients with persistent (>1 year) postconcussive symptoms following mild blunt head trauma. A retrospective and blind review of imaging data with respect to the presence of specific somatic, psychiatric, and cognitive complaints. Thirty complete data sets (with MRI, SPECT, MEG, and neuropsychological testing results) were collected between 1994 and 2000 from the MEG programs at the Albuquerque VAMC and the University of Utah. MRI data were evaluated for focal and diffuse structural abnormalities, SPECT data for regions of hypoperfusion, and resting MEG data for abnormal dipolar slow wave activity (DSWA) and epileptiform transients. Structural MRI was abnormal for 4 patients. SPECT showed regions of hypoperfusion in 12 patients, while MEG showed abnormal activity in 19 patients. None of the imaging methods produced findings statistically associated with postconcussive psychiatric symptoms. A significant association was found between basal ganglia hypoperfusion and postconcussive headaches. For patients with cognitive complaints, abnormalities were more likely to be detected by MEG (86%) than either SPECT (40%) or MRI (18%) (P<.01). MEG also revealed significant (P<.01) associations between temporal lobe DSWA and memory problems, parietal DSWA and attention problems, and frontal DSWA and problems in executive function. Functional brain imaging data collected in a resting state can provide objective evidence of brain injury in mild blunt head trauma patients with persistent postconcussive somatic and/or cognitive symptoms. MEG proved to be particularly informative for patients with cognitive symptoms.

  7. Role of auditory brain function assessment by SPECT in cochlear implant side selection.

    PubMed

    Di Nardo, W; Giannantonio, S; Di Giuda, D; De Corso, E; Schinaia, L; Paludetti, G

    2013-02-01

    Pre-surgery evaluation, indications for cochlear implantation and expectations in terms of post-operative functional results remain challenging topics in pre-lingually deaf adults. Our study has the purpose of determining the benefits of Single Photon Emission Tomography (SPECT) assessment in pre-surgical evaluation of pre-lingually deaf adults who are candidates for cochlear implantation. In 7 pre-lingually profoundly deaf patients, brain SPECT was performed at baseline conditions and in bilateral simultaneous multi-frequency acoustic stimulation. Six sagittal tomograms of both temporal cortices were used for semi-quantitative analysis in each patient. Percentage increases in cortical perfusion resulting from auditory stimulation were calculated. The results showed an inter-hemispherical asymmetry of the activation extension and intensity in the stimulated temporal areas. Consistent with the obtained brain activation data, patients were implanted preferring the side that showed higher activation after acoustic stimulus. Considering the increment in auditory perception performances, it was possible to point out a relationship between cortical brain activity shown by SPECT and hearing performances, and, even more significant, a correlation between post-operative functional performances and the activation of the most medial part of the sagittal temporal tomograms, corresponding to medium-high frequencies. In light of these findings, we believe that brain SPECT could be considered in the evaluation of deaf patients candidate for cochlear implantation, and that it plays a major role in functional assessment of the auditory cortex of pre-lingually deaf subjects, even if further studies are necessary to conclusively establish its utility. Further developments of this technique are possible by using trans-tympanic electrical stimulation of the cochlear promontory, which could give the opportunity to study completely deaf patients, whose evaluation is objectively difficult

  8. A Silicon SPECT System for Molecular Imaging of the Mouse Brain.

    PubMed

    Shokouhi, Sepideh; Fritz, Mark A; McDonald, Benjamin S; Durko, Heather L; Furenlid, Lars R; Wilson, Donald W; Peterson, Todd E

    2007-01-01

    We previously demonstrated the feasibility of using silicon double-sided strip detectors (DSSDs) for SPECT imaging of the activity distribution of iodine-125 using a 300-micrometer thick detector. Based on this experience, we now have developed fully customized silicon DSSDs and associated readout electronics with the intent of developing a multi-pinhole SPECT system. Each DSSD has a 60.4 mm × 60.4 mm active area and is 1 mm thick. The strip pitch is 59 micrometers, and the readout of the 1024 strips on each side gives rise to a detector with over one million pixels. Combining four high-resolution DSSDs into a SPECT system offers an unprecedented space-bandwidth product for the imaging of single-photon emitters. The system consists of two camera heads with two silicon detectors stacked one behind the other in each head. The collimator has a focused pinhole system with cylindrical-shaped pinholes that are laser-drilled in a 250 μm tungsten plate. The unique ability to collect projection data at two magnifications simultaneously allows for multiplexed data at high resolution to be combined with lower magnification data with little or no multiplexing. With the current multi-pinhole collimator design, our SPECT system will be capable of offering high spatial resolution, sensitivity and angular sampling for small field-of-view applications, such as molecular imaging of the mouse brain.

  9. Functional brain abnormalities localized in 55 chronic tinnitus patients: fusion of SPECT coincidence imaging and MRI.

    PubMed

    Farhadi, Mohammad; Mahmoudian, Saeid; Saddadi, Fariba; Karimian, Ali Reza; Mirzaee, Mohammad; Ahmadizadeh, Majid; Ghasemikian, Khosro; Gholami, Saeid; Ghoreyshi, Esmaeel; Beyty, Saeid; Shamshiri, Ahmadreza; Madani, Sedighe; Bakaev, Valery; Moradkhani, Seddighe; Raeisali, Gholamreza

    2010-04-01

    Tinnitus is often defined as the perception of sounds or noise in the absence of any external auditory stimuli. The pathophysiology of subjective idiopathic tinnitus remains unclear. The aim of this study was to investigate the functional brain activities and possible involved cerebral areas in subjective idiopathic tinnitus patients by means of single photon emission computerized tomography (SPECT) coincidence imaging, which was fused with magnetic resonance imaging (MRI). In this cross-sectional study, 56 patients (1 subject excluded) with subjective tinnitus and 8 healthy controls were enrolled. After intravenous injection of 5 mCi F18-FDG (fluorodeoxyglucose), all subjects underwent a brain SPECT coincidence scan, which was then superimposed on their MRIs. In the eight regions of interest (middle temporal, inferotemporal, medial temporal, lateral temporal, temporoparietal, frontal, frontoparietal, and parietal areas), the more pronounced values were represented in medial temporal, inferotemporal, and temporoparietal areas, which showed more important proportion of associative auditory cortices in functional attributions of tinnitus than primary auditory cortex. Brain coincidence SPECT scan, when fused on MRI is a valuable technique in the assessment of patients with tinnitus and could show the significant role of different regions of central nervous system in functional attributions of tinnitus.

  10. Functional brain abnormalities localized in 55 chronic tinnitus patients: fusion of SPECT coincidence imaging and MRI

    PubMed Central

    Farhadi, Mohammad; Mahmoudian, Saeid; Saddadi, Fariba; Karimian, Ali Reza; Mirzaee, Mohammad; Ahmadizadeh, Majid; Ghasemikian, Khosro; Gholami, Saeid; Ghoreyshi, Esmaeel; Beyty, Saeid; Shamshiri, Ahmadreza; Madani, Sedighe; Bakaev, Valery; Moradkhani, Seddighe; Raeisali, Gholamreza

    2010-01-01

    Tinnitus is often defined as the perception of sounds or noise in the absence of any external auditory stimuli. The pathophysiology of subjective idiopathic tinnitus remains unclear. The aim of this study was to investigate the functional brain activities and possible involved cerebral areas in subjective idiopathic tinnitus patients by means of single photon emission computerized tomography (SPECT) coincidence imaging, which was fused with magnetic resonance imaging (MRI). In this cross-sectional study, 56 patients (1 subject excluded) with subjective tinnitus and 8 healthy controls were enrolled. After intravenous injection of 5 mCi F18-FDG (fluorodeoxyglucose), all subjects underwent a brain SPECT coincidence scan, which was then superimposed on their MRIs. In the eight regions of interest (middle temporal, inferotemporal, medial temporal, lateral temporal, temporoparietal, frontal, frontoparietal, and parietal areas), the more pronounced values were represented in medial temporal, inferotemporal, and temporoparietal areas, which showed more important proportion of associative auditory cortices in functional attributions of tinnitus than primary auditory cortex. Brain coincidence SPECT scan, when fused on MRI is a valuable technique in the assessment of patients with tinnitus and could show the significant role of different regions of central nervous system in functional attributions of tinnitus. PMID:20068582

  11. Three modality image registration of brain SPECT/CT and MR images for quantitative analysis of dopamine transporter imaging

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Yuzuho; Takeda, Yuta; Hara, Takeshi; Zhou, Xiangrong; Matsusako, Masaki; Tanaka, Yuki; Hosoya, Kazuhiko; Nihei, Tsutomu; Katafuchi, Tetsuro; Fujita, Hiroshi

    2016-03-01

    Important features in Parkinson's disease (PD) are degenerations and losses of dopamine neurons in corpus striatum. 123I-FP-CIT can visualize activities of the dopamine neurons. The activity radio of background to corpus striatum is used for diagnosis of PD and Dementia with Lewy Bodies (DLB). The specific activity can be observed in the corpus striatum on SPECT images, but the location and the shape of the corpus striatum on SPECT images only are often lost because of the low uptake. In contrast, MR images can visualize the locations of the corpus striatum. The purpose of this study was to realize a quantitative image analysis for the SPECT images by using image registration technique with brain MR images that can determine the region of corpus striatum. In this study, the image fusion technique was used to fuse SPECT and MR images by intervening CT image taken by SPECT/CT. The mutual information (MI) for image registration between CT and MR images was used for the registration. Six SPECT/CT and four MR scans of phantom materials are taken by changing the direction. As the results of the image registrations, 16 of 24 combinations were registered within 1.3mm. By applying the approach to 32 clinical SPECT/CT and MR cases, all of the cases were registered within 0.86mm. In conclusions, our registration method has a potential in superimposing MR images on SPECT images.

  12. Tl-201 and Tc-99m-Sestamibi SPECT for brain tumor detection: Comparison using MRI coregistration

    SciTech Connect

    Darcourt, J.; Itti, L.; Chang, L.

    1994-05-01

    Tl-201 (Tl) brain SPECT has been validated for the differential diagnosis of high versus low grade gliomas and recurrence versus radiation necrosis. We compared this technique to Tc-99m-Sestamibi (MIBI) SPECT in 9 patients (pts) with brain tumors using MRI coregistration. Pts were injected with 4 mCi of Tl and brain SPECT was performed using a dedicated brain system. This was immediately following by an injection of 20 mCi of MIBI and a brain SPECT using the same camera and with the pt in the same position. Four pts were studied for the diagnosis of radiation necrosis vs. tumor recurrence (2 had biopsy proven recurrence); 5 pts were studied for primary tumor evaluation: 2 meningiomas, 1 oligodendroglioma, 1 low-grade astrocytoma, 1 cysticercosis. Coregistration was performed for every pt by 3D surface fitting of the inner skull MIBI contour to the MRI brain surface extracted automatically. ROIs were drawn on the MRI and applied to the coregistered MIBI and Tl images for tumor to non-tumor ratios T/NT calculations. There was a tight correlation between MIBI and Tl T/NT (r-0.96) and a 1.5 threshold separated radiation necrosis from recurrence and low from high grade primary tumors. Therefore, the data already available on Tl brain tumor imaging can be used with MIBI SPECT with the advantage of a better image quality (2.5 to 4 times more counts).

  13. Functional brain substrate of quality of life in patients with schizophrenia: A brain SPECT multidimensional analysis.

    PubMed

    Faget-Agius, Catherine; Boyer, Laurent; Richieri, Raphaëlle; Auquier, Pascal; Lançon, Christophe; Guedj, Eric

    2016-03-30

    The aim of this study was to investigate the functional brain substrate of quality of life (QoL) in patients with schizophrenia. Participants comprised 130 right-handed patients with schizophrenia who underwent whole-brain single photon emission computed tomography (SPECT) with (99m)Tc-labeled ethylcysteinate dimer ((99m)Tc-ECD) for exploring correlations of regional cerebral blood flow (rCBF) with the eight dimensions score of the Schizophrenia Quality of Life questionnaire (S-QoL 18). A significant positive correlation was found between the global index of the S-QoL 18 and rCBF in the right superior temporal sulcus and between psychological well-being dimension and rCBF in Brodmann area (BA)6, BA8, BA9, and BA10 and between self-esteem dimension and rCBF in striatum and between family relationship dimension and rCBF in BA1, BA2, BA3, BA4, BA8, BA22, BA40, BA42 and BA44 and between relationship with friends dimension and rCBF in BA44 and between physical well-being dimension and rCBF in parahippocampal gyrus, and finally between autonomy dimension and rCBF in cuneus and precuneus. A significant negative correlation was found between resilience dimension and rCBF in precuneus and between sentimental life dimension and rCBF in BA10. Our findings provide neural correlates of QoL. Brain regions involved in cognitions, emotional information processing and social cognition underlie the different QoL dimensions. Copyright © 2016. Published by Elsevier Ireland Ltd.

  14. Cortical neuron loss in post-traumatic higher brain dysfunction using (123)I-iomazenil SPECT.

    PubMed

    Nakagawara, Jyoji; Kamiyama, Kenji; Takahashi, Masaaki; Nakamura, Hirohiko

    2013-01-01

    In patients with higher brain dysfunction (HBD) after mild traumatic brain injury (MTBI), diagnostic imaging of cortical neuron loss in the frontal lobes was studied using SPECT with (123)I-iomazenil (IMZ), as a radioligand for central benzodiazepine receptor (BZR). Statistical imaging analysis using three-dimensional stereotactic surface projections (3D-SSP) for (123)I-IMZ SPECT was performed in 17 patients. In all patients with HBD defined by neuropsychological tests, cortical neuron loss was indicated in the bilateral medial frontal lobes in 14 patients (83 %). A comparison between the group of 17 patients and the normal database demonstrated common areas of cortical neuron loss in the bilateral medial frontal lobes involving the medial frontal gyrus (MFG) and the anterior cingulate gyrus (ACG). In an assessment of cortical neuron loss in the frontal medial cortex using the stereotactic extraction estimation (SEE) method (level 3), significant cortical neuron loss was observed within bilateral MFG in 9 patients and unilateral MFG in 4, and bilateral ACG in 12 and unilateral ACG in 3. Fourteen patients showed significant cortical neuron loss in bilateral MFG or ACG. In patients with MTBI, HBD seemed to correlate with selective cortical neuron loss within the bilateral MFG or ACG where the responsible lesion could be. 3D-SSP and SEE level 3 analysis for (123)I-IMZ SPECT could be valuable for diagnostic imaging of HBD after MTBI.

  15. Brain SPECT guided repetitive transcranial magnetic stimulation (rTMS) in treatment resistant major depressive disorder.

    PubMed

    Jha, Shailesh; Chadda, Rakesh K; Kumar, Nand; Bal, C S

    2016-06-01

    Repetitive transcranial magnetic stimulation (rTMS) has emerged as a potential treatment in treatment resistant major depressive disorder (MDD). However, there is no consensus about the exact site of stimulation for rTMS. Single-photon emission computed tomography (SPECT) offers a potential technique in deciding the site of stimulation. The present study was conducted to assess the difference in outcome of brain SPECT assisted rTMS versus standard protocol of twenty sessions of high frequency rTMS as add on treatment in 20 patients with treatment resistant MDD, given over a period of 4 weeks. Thirteen subjects (group I) received high frequency rTMS over an area of hypoperfusion in the prefrontal cortex, as identified on SPECT, whereas 7 subjects (group II) were administered rTMS in the left dorsoslateral prefrontal cortex (DLPFC) area. Improvement was monitored using standardized instruments. Patients in the group I showed a significantly better response compared to those in the group II. In group I, 46% of the subjects were responders on MADRS, 38% on BDI and 77% on CGI. The parallel figures of responders in Group II were 0% on MADRS, 14% on BDI and 43% on CGI. There were no remitters in the study. No significant untoward side effects were noticed. The study had limitations of a small sample size and non-controlled design, and all the subjects were also receiving the standard antidepressant therapy. Administration of rTMS over brain SPECT specified area of hypoperfusion may have a better clinical outcome compared to the standard protocol.

  16. Evolution of technetium-99m-HMPAO SPECT and brain mapping in a patient presenting with echolalia and palilalia.

    PubMed

    Dierckx, R A; Saerens, J; De Deyn, P P; Verslegers, W; Marien, P; Vandevivere, J

    1991-08-01

    A 78-yr-old woman presented with transient echolalia and palilalia. She had suffered from Parkinson's disease for 2 yr. Routine laboratory examination showed hypotonic hyponatremia, but was otherwise unremarkable. Brain mapping revealed a bifrontal delta focus, more pronounced on the right. Single photon emission computed tomography (SPECT) of the brain with technetium-99m labeled d,l hexamethylpropylene-amine oxime (99mTc-HMPAO), performed during the acute episode showed relative frontoparietal hypoactivity. Brain mapping performed after disappearance of the echolalia and palilalia, which persisted only for 1 day, was normal. By contrast, SPECT findings persisted for more than 3 wk. Features of particular interest in the presented patient are the extensive defects seen on brain SPECT despite the absence of morphologic lesions, the congruent electrophysiologic changes and their temporal relationship with the clinical evolution.

  17. SPECT brain perfusion imaging with Tc-99m ECD: Semi-quantitative regional analysis and database mapping

    SciTech Connect

    Schiepers, C.; Hegge, J.; De Roo, M.

    1994-05-01

    Brain SPECT is a well accepted method for the assessment of brain perfusion in various disorders such as epilepsy, stroke, dementia. A program for handling the tomographic data was developed, using a commercial spreadsheet (Microsoft EXCEL) with a set of macro`s for analysis, graphic display and database management of the final results.

  18. Quantitative I-123-IMP brain SPECT and neuropsychological testing in AIDS dementia

    SciTech Connect

    Kuni, C.C.; Rhame, F.S.; Meier, M.J.; Foehse, M.C.; Loewenson, R.B.; Lee, B.C.; Boudreau, R.J.; duCret, R.P. )

    1991-03-01

    We performed I-123-IMP SPECT brain imaging on seven mildly demented AIDS patients and seven normal subjects. In an attempt to detect and quantitate regions of decreased I-123-IMP uptake, pixel intensity histograms of normalized SPECT images at the basal ganglia level were analyzed for the fraction of pixels in the lowest quartile of the intensity range. This fraction (F) averaged 17.5% (S.D. = 4.6) in the AIDS group and 12.6% (S.D. = 5.1) in the normal group (p less than .05). Six of the AIDS patients underwent neuropsychological testing (NPT). NPT showed the patients to have a variety of mild abnormalities. Regression analysis of NPT scores versus F yielded a correlation coefficient of .80 (p less than .05). We conclude that analysis of I-123-IMP SPECT image pixel intensity distribution is potentially sensitive in detecting abnormalities associated with AIDS dementia and may correlate with the severity of dementia as measured by NPT.

  19. Brain SPECT with short focal-length cone-beam collimation

    SciTech Connect

    Park, Mi-Ae; Moore, Stephen C.; Kijewski, Marie Foley

    2005-07-15

    Single-photon emission-computed tomography (SPECT) imaging of deep brain structures is compromised by loss of photons due to attenuation. We have previously shown that a centrally peaked collimator sensitivity function can compensate for this phenomenon, increasing sensitivity over most of the brain. For dual-head instruments, parallel-hole collimators cannot provide variable sensitivity without simultaneously degrading spatial resolution near the center of the brain; this suggests the use of converging collimators. We have designed collimator pairs for dual-head SPECT systems to increase sensitivity, particularly in the center of the brain, and compared the new collimation approach to existing approaches on the basis of performance in estimating activity concentration of small structures at various locations in the brain. The collimator pairs we evaluated included a cone-beam collimator, for increased sensitivity, and a fan-beam collimator, for data sufficiency. We calculated projections of an ellipsoidal uniform background, with 0.9-cm-radius spherical lesions at several locations in the background. From these, we determined ideal signal-to-noise ratios (SNR{sub CRB}) for estimation of activity concentration within the spheres, based on the Cramer-Rao lower bound on variance. We also reconstructed, by an ordered-subset expectation-maximization (OS-EM) procedure, images of this phantom, as well as of the Zubal brain phantom, to allow visual assessment and to ensure that they were free of artifacts. The best of the collimator pairs evaluated comprised a cone-beam collimator with 20 cm focal length, for which the focal point is inside the brain, and a fan-beam collimator with 40 cm focal length. This pair yielded increased SNR{sub CRB}, compared to the parallel-parallel pair, throughout the imaging volume. The factor by which SNR{sub CRB} increased ranged from 1.1 at the most axially extreme location to 3.5 at the center. The gains in SNR{sub CRB} were relatively

  20. Brain SPECT and transcranial Doppler (TCD) evaluation of the effects of intra-arterial papaverine for cerebral vasospasm

    SciTech Connect

    Lewis, D.H.; Newell, D.W.; Eskridge, J.M.

    1994-05-01

    Cerebral vasospasm (cv) is a common and serious consequence of subarachnoid hemorrhage. Interventional neuroradiologic techniques for treating cv refractory to medical and hemodynamic measures have included transluminal microballoon angioplasty and intra-arterial papaverine infusion (pap). Eight patients (pts) who had symptomatic cv but were not candidates for microballoon angioplasty received pap via arterial catheter. All 8 pts had brain SPECT with Tc-99m HMPAO and 7 had TCD readings before and after treatment. One pt had 2 separate treatments. Total treatments = 9. Results: Of the total of 9 treatments: 5 demonstrated marked improvement in regional cerebral blood flow on SPECT in the vascular territories that were ischemic, 3 showed mild to moderate improvement of blood flow, and 1 was unchanged. The pt that did not improve on SPECT died due to cardiorespiratory problems but remained comatose without neurologic improvement after the treatment. The other 8 had either prompt clinical improvement or modestly delayed improvement due to concomitant hydrocephalus. infection, recurrent vasospasm or other intervening medical problems. TCD readings in the treated vessels showed improved (lower) velocities that agreed with SPECT improvement after 4 intra-arterial pap treatments. There were 4 discrepancies of SPECT and TCD: 1 with rising TCD velocity in the mild cv range in the treated vessel that demonstrated SPECT improvement; 1 with unchanged velocity in the moderate cv range that showed SPECT improvement; 1 that showed lower velocity in the moderate cv range while the SPECT was unchanged; and 1 that had normal TCD velocities before and after treatment but high pulsatility indices on Doppler (which are characteristic of either elevated intra-cranial pressure or distal vessel disease) who had mild to moderate improvement of blood flow on SPECT after treatment.

  1. Clinical Utility of SPECT Neuroimaging in the Diagnosis and Treatment of Traumatic Brain Injury: A Systematic Review

    PubMed Central

    Raji, Cyrus A.; Tarzwell, Robert; Pavel, Dan; Schneider, Howard; Uszler, Michael; Thornton, John; van Lierop, Muriel; Cohen, Phil; Amen, Daniel G.; Henderson, Theodore

    2014-01-01

    Purpose This systematic review evaluated the clinical utility of single photon emission computed tomography (SPECT) in traumatic brain injury (TBI). Methods After defining a PICO Statement (Population, Intervention, Comparison and Outcome Statement), PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria were applied to identify 1600 articles. After screening, 374 articles were eligible for review. Inclusion for review was focus on SPECT in the setting of mild, moderate, or severe TBI with cerebral lobar specificity of SPECT findings. Other inclusion criteria were comparison modalities in the same subjects and articles in English. Foreign language articles, SPECT studies that did not include comparison modalities, and case reports were not included for review. Results We identified 19 longitudinal and 52 cross-sectional studies meeting inclusion criteria. Three longitudinal studies examined diagnostic predictive value. The first showed positive predictive value increases from initial SPECT scan shortly after trauma to one year follow up scans, from 59% to 95%. Subsequent work replicated these results in a larger cohort. Longitudinal and cross sectional studies demonstrated SPECT lesion localization not detected by CT or MRI. The most commonly abnormal regions revealed by SPECT in cross-sectional studies were frontal (94%) and temporal (77%) lobes. SPECT was found to outperform both CT and MRI in both acute and chronic imaging of TBI, particularly mild TBI. It was also found to have a near 100% negative predictive value. Conclusions This review demonstrates Level IIA evidence (at least one non-randomized controlled trial) for the value of SPECT in TBI. Given its advantages over CT and MRI in the detection of mild TBI in numerous studies of adequate quality, and given its excellent negative predictive value, it may be an important second test in settings where CT or MRI are negative after a closed head injury with post

  2. SPECT imaging for brain improvement quantification in a patient with cerebrotendinous xanthomatosis.

    PubMed

    Selva-O'Callaghan, Albert; Bardes, Ignasi; Jacas, Carlos; Jubany, Lluis; Lorenzo-Bosquet, Carles; Cuberas-Borrós, Gemma; Vilardell-Tarres, Miquel

    2011-01-01

    Cerebrotendinous xanthomatosis is a rare recessive autosomal disease caused by mutations of the sterol 27-hydroxylase gene (CYP27), which leads to reduced synthesis of bile acids, particularly chenodeoxycholic acid (Cali et al, J Biol Chem. 1991;266:7779-7783; Gallus et al, Neurol Sci. 2006;27:143-149). The disease is characterized by progressive neurologic dysfunction due to accumulation of cholestanol in neurologic tissues (Moghadasian et al, Arch Neurol. 2002;59:527-529; Selva-O'Callaghan et al, Rheumatology. 2007;46:1212-1213). Long-term treatment with chenodeoxycholic acid can arrest or even reverse progression of the disease (Pierre et al, J Inherit Metab Dis. In press).Brain SPECT with 740 MBq of Tc-99m ethyl cysteinate dimmer, using a double-head gamma camera (Siemens E.cam) with high-resolution, low-energy parallel collimators was performed in our patient at onset and 2 years after starting chenodeoxycholic acid treatment. SPECT acquisitions were performed using a 360-degree orbit, 1 image/30 seg/3 degree, and 128 × 128 matrix. Reconstruction was by means of filtered back-projection, Butterworth 5/0.25, without attenuation correction. Pre- and post-SPECT dicom images were reoriented into Talairach space using NeuroGam (Segami Corporation). To visually identify abnormal perfusion regions, volume render brain image was computed, where abnormal perfusion regions were found by comparing with age-matched normal database, and Brodmann areas (BA) were quantified. Pre- versus post-treatment changes were computed by means of relative percentage between counts. Post-treatment SPECT showed better perfusion than pretreatment SPECT with an increase between 5% and 10% in frontal cortex (BA 9, BA 24, BA 32, BA 46, BA 47), parietal cortex (BA 5, BA 31), and temporal cortex (BA 20, BA 22, BA 28, BA 36, BA 37, BA 38), and with an increase of more than 10% in frontal cortex (BA 45) and parietal cortex (BA 23). This case illustrates the benefit of bile acid therapy for

  3. Simulation of realistic abnormal SPECT brain perfusion images: application in semi-quantitative analysis

    NASA Astrophysics Data System (ADS)

    Ward, T.; Fleming, J. S.; Hoffmann, S. M. A.; Kemp, P. M.

    2005-11-01

    Simulation is useful in the validation of functional image analysis methods, particularly when considering the number of analysis techniques currently available lacking thorough validation. Problems exist with current simulation methods due to long run times or unrealistic results making it problematic to generate complete datasets. A method is presented for simulating known abnormalities within normal brain SPECT images using a measured point spread function (PSF), and incorporating a stereotactic atlas of the brain for anatomical positioning. This allows for the simulation of realistic images through the use of prior information regarding disease progression. SPECT images of cerebral perfusion have been generated consisting of a control database and a group of simulated abnormal subjects that are to be used in a UK audit of analysis methods. The abnormality is defined in the stereotactic space, then transformed to the individual subject space, convolved with a measured PSF and removed from the normal subject image. The dataset was analysed using SPM99 (Wellcome Department of Imaging Neuroscience, University College, London) and the MarsBaR volume of interest (VOI) analysis toolbox. The results were evaluated by comparison with the known ground truth. The analysis showed improvement when using a smoothing kernel equal to system resolution over the slightly larger kernel used routinely. Significant correlation was found between effective volume of a simulated abnormality and the detected size using SPM99. Improvements in VOI analysis sensitivity were found when using the region median over the region mean. The method and dataset provide an efficient methodology for use in the comparison and cross validation of semi-quantitative analysis methods in brain SPECT, and allow the optimization of analysis parameters.

  4. Brain perfusion SPECT with Brodmann areas analysis in differentiating frontotemporal dementia subtypes.

    PubMed

    Valotassiou, Varvara; Papatriantafyllou, John; Sifakis, Nikolaos; Tzavara, Chara; Tsougos, Ioannis; Psimadas, Dimitrios; Kapsalaki, Eftychia; Fezoulidis, Ioannis; Hadjigeorgiou, George; Georgoulias, Panagiotis

    2014-01-01

    Despite the known validity of clinical diagnostic criteria, significant overlap of clinical symptoms between Frontotemporal dementia (FTD) subtypes exists in several cases, resulting in great uncertainty of the diagnostic boundaries. We evaluated the perfusion between FTD subtypes using brain perfusion (99m)Tc-HMPAO SPECT with Brodmann areas (BA) mapping. NeuroGam software was applied on single photon emission computed tomographic (SPECT) studies for the semi-quantitative evaluation of perfusion in BA and the comparison with the software's normal database. We studied 91 consecutive FTD patients: 21 with behavioural variants (bvFTD), 39 with language variants (lvFTD) [12 with progressive non-fluent aphasia (PNFA), 27 with semantic dementia (SD)], and 31 patients with progressive supranuclear palsy (PSP)/corticobasal degeneration (CBD). Stepwise logistic regression analyses showed that the BA 28L and 32R could independently differentiate bvFTD from lvFTD, while the BA 8R and 25R could discriminate bvFTD from SD and PNFA, respectively. Additionally, BA 7R and 32R were found to discriminate bvFTD from CBD/PSP. The only BA that could differentiate SD from PNFA was 6L. BA 6R and 20L were found to independently differentiate CBD/PSP from lvFTD. Moreover, BA 20L and 22R could discriminate CBD/PSP from PNFA, while BA 6R, 20L and 45R were found to independently discriminate CBD/PSP from SD. Brain perfusion SPECT with BA mapping can be a useful additional tool in differentiating FTD variants by improving the definition of brain areas that are specifically implicated, resulting in a more accurate differential diagnosis in atypical or uncertain forms of FTD.

  5. PET and SPECT in whiplash syndrome: a new approach to a forgotten brain?

    PubMed Central

    Otte, A; Ettlin, T; Nitzsche, E; Wachter, K; Hoegerle, S; Simon, G; Fierz, L; Moser, E; Mueller-Brand, J

    1997-01-01

    Whiplash associated disorders are a medicolegally controversial condition becoming increasingly worrisome in the western world. This study was designed to evaluate perfusion and glucose metabolism in whiplash brain. Using Tc-99m-bicisate (ECD) single photon emission computed tomography (SPECT) and F-18-fluorodeoxyglucose (FDG) PET, six clinically and neuropsychologically controlled patients (patient group) with whiplash syndrome and 12 normal controls (control group) were investigated. Standardised elliptical regions of interest (ROIs) were determined in three adjacent transaxial slices in the frontal, parietal, temporal, and parieto-occipital cortex, cerebellum, brain stem, basal ganglia, and thalamus. For PET, the glucose metabolic index (GMI; =ROI uptake/global uptake at the level of the basal ganglia) and, for SPECT, the perfusion index (PI; =ROI/global) were calculated. In the patient group there was significant hypometabolism and hypoperfusion in the parieto-occipital regions (on the right (R) and left (L) side) compared with the control group: PET data: GMI parieto-occipital R: control 1.066 (0.081) (mean (SD)), patient 0.946 (0.065); P=0.0092, Mann Whitney. GMI parieto-occipital L: control 1.034 (0.051), patient 0.922 (0.073); p=0.0067. SPECT data: PI parieto-occipital R: control 1.262 (0.066), patient 1.102 (0.063); P=0.0039. PI parieto-occipital L: control 1.226 (0.095), patient 1.098 (0.075); P=0.0273. In some patients there was hypometabolism (>2 SD of control) in regions other than the parieto-occipital region. It is hypothesised that parieto-occipital hypometabolism may be caused by activation of nociceptive afferent nerves from the upper cervical spine.

 PMID:9328255

  6. The clinical impact of SPECT/PET co-registration with MRI in patients with brain tumors

    SciTech Connect

    Macapinlac, H.A.; Scott, A.M.; Zhang, J.J.

    1994-05-01

    We wanted to evaluate the clinical impact of co-registering SPECT and PET images with MRI (Gd-DTPA) in brain tumor patients. 81 patients with known or suspected brain tumors had 168 SPECT and/or PET scans which were difficult to interpret were coregistered with MRI. A modified Pellizari/Chen surface matching algorithm was used to fit the SPECT/PET and MR images. Impact of the technique on interpretation of the scans was defined as (A) no effect, (B) moderate effect (better localize abnormal uptake to suspected tumor and distinguish normal activity from tumor), (C) basis for final interpretation (distinguish tumor from necrosis, localize biopsy site, find occult tumor, grading of tumor). Impact on patient management was defined as (A) no effect, (B) altered diagnostic/treatment decision (continuation of conservative care, or justify chemo or radiation), (C) basis for treatment (direct biopsy, surgery, and/or radiation).

  7. Design and simulation of a full-ring multi-lofthole collimator for brain SPECT

    NASA Astrophysics Data System (ADS)

    Van Audenhaege, Karen; Vandenberghe, Stefaan; Deprez, Karel; Vandeghinste, Bert; Van Holen, Roel

    2013-09-01

    Currently, clinical brain single photon emission computed tomography (SPECT) is mostly performed using rotating dual-head gamma cameras equipped with low-energy-high-resolution parallel-beam collimators (LEHR PAR). The resolution of these systems is rather poor (8-10 mm) and the rotation of the heavy gamma cameras can introduce misalignment errors. Therefore, we designed a static full-ring multi-lofthole brain SPECT insert for an existing ring of LaBr3 (5% Ce) detectors. The novelty of the design is found in the shutter mechanism that makes the system very flexible and eliminates the need for rotating parts. A stationary SPECT insert is not only more robust, it is also easier to integrate in a magnetic resonance imaging system (MRI) for simultaneous SPECT-MRI. The target spatial resolution of our design is 6 mm. In this study we used analytical calculations to optimize the collimator for an existing ring of LaBr3 (5% Ce) detectors. We fixed the target spatial resolution at 6 mm in the center of the field-of-view and maximized the volume sensitivity by changing the collimator radius, the aperture and the number of loftholes. Based on these optimal parameters we simulated phantom data and evaluated the image quality of our multi-lofthole system. We simulated a noiseless uniform and Defrise phantom to assess artifacts and sampling completeness and a noiseless hot-rod phantom to assess the reconstructed spatial resolution. We visually evaluated a simulated noisy Hoffman phantom with two lesions. Then, we evaluated the non-prewhitening matched filter signal-to-noise ratio (NPW-SNR) in two lesion detectability phantoms: one with hot lesions and one with cold lesions. Finally, a contrast-to-noise (CNR) study was performed on a phantom with both hot and cold lesions of different sizes (6-16 mm). All results were compared to a LEHR PAR system. The optimization resulted in a final collimator design with a volume sensitivity of 1.55 × 10-4 cps Bq-1, which is 2.5 times lower

  8. Design and simulation of a full-ring multi-lofthole collimator for brain SPECT.

    PubMed

    Van Audenhaege, Karen; Vandenberghe, Stefaan; Deprez, Karel; Vandeghinste, Bert; Van Holen, Roel

    2013-09-21

    Currently, clinical brain single photon emission computed tomography (SPECT) is mostly performed using rotating dual-head gamma cameras equipped with low-energy-high-resolution parallel-beam collimators (LEHR PAR). The resolution of these systems is rather poor (8-10 mm) and the rotation of the heavy gamma cameras can introduce misalignment errors. Therefore, we designed a static full-ring multi-lofthole brain SPECT insert for an existing ring of LaBr3 (5% Ce) detectors. The novelty of the design is found in the shutter mechanism that makes the system very flexible and eliminates the need for rotating parts. A stationary SPECT insert is not only more robust, it is also easier to integrate in a magnetic resonance imaging system (MRI) for simultaneous SPECT-MRI. The target spatial resolution of our design is 6 mm. In this study we used analytical calculations to optimize the collimator for an existing ring of LaBr3 (5% Ce) detectors. We fixed the target spatial resolution at 6 mm in the center of the field-of-view and maximized the volume sensitivity by changing the collimator radius, the aperture and the number of loftholes. Based on these optimal parameters we simulated phantom data and evaluated the image quality of our multi-lofthole system. We simulated a noiseless uniform and Defrise phantom to assess artifacts and sampling completeness and a noiseless hot-rod phantom to assess the reconstructed spatial resolution. We visually evaluated a simulated noisy Hoffman phantom with two lesions. Then, we evaluated the non-prewhitening matched filter signal-to-noise ratio (NPW-SNR) in two lesion detectability phantoms: one with hot lesions and one with cold lesions. Finally, a contrast-to-noise (CNR) study was performed on a phantom with both hot and cold lesions of different sizes (6-16 mm). All results were compared to a LEHR PAR system. The optimization resulted in a final collimator design with a volume sensitivity of 1.55 × 10(-4) cps Bq(-1), which is 2.5

  9. Brain imaging with sup 123 I-IMP-SPECT in migraine between attacks

    SciTech Connect

    Schlake, H.P.; Boettger, I.G.G.; Grotemeyer, K.H.; Husstedt, I.W.

    1989-06-01

    {sup 123}I-IMP-SPECT brain imaging was performed in patients with classic migraine (n = 5) and migraine accompagnee (n = 18) during the headache-free interval. A regional reduction of tracer uptake into brain was observed in all patients with migraine accompagnee, while in patients with classic migraine only one case showed an area of decreased activity. The most marked alteration was found in a patient with persisting neurological symptoms (complicated migraine). In most cases the areas of decreased tracer uptake corresponded to headache localization as well as to topography of neurologic symptoms during migraine attacks. It may be concluded that migraine attacks occur in connection with exacerbations of preexisting changes of cerebral autoregulation due to endogenous or exogenous factors.

  10. Ligands for SPECT and PET imaging of muscarinic-cholinergic receptors of the heart and brain

    SciTech Connect

    Knapp, F.F. Jr.; McPherson, D.W.; Luo, H.

    1995-06-01

    Interest in the potential use of cerebral SPECT and PET imaging for determination of the density and activity of muscarinic-cholinergic receptors (mAChR) has been stimulated by the changes in these receptors which occur in many neurological diseases. In addition, the important involvement of mAChR in modulating negative inotropic cardiac activity suggests that such receptor ligands may have important applications in evaluation of changes which may occur in cardiac disease. In this paper, the properties of several key muscarinic receptor ligands being developed or which have been used for clinical SPECT and PET are discussed. In addition, the ORNL development of the new iodinated IQNP ligand based on QNB and the results of in vivo biodistribution studies in rats, in vitro competitive binding studies and ex vivo autoradiographic experiments are described. The use of radioiodinated IQNP may offer several advantages in comparison to IQNB because of its easy and high yield preparation and high brain uptake and the potential usefulness of the {open_quotes}partial{close_quotes} subtype selective IONP isomers. We also describe the development of new IQNP-type analogues which offer the opportunity for radiolabeling with positron-emitting radioisotopes (carbon-11, fluorine-18 and bromine-76) for potential use with PET.

  11. Evaluation of linear registration algorithms for brain SPECT and the errors due to hypoperfusion lesions.

    PubMed

    Radau, P E; Slomka, P J; Julin, P; Svensson, L; Wahlund, L O

    2001-08-01

    The semiquantitative analysis of perfusion single-photon emission computed tomography (SPECT) images requires a reproducible, objective method. Automated spatial standardization (registration) of images is a prerequisite to this goal. A source of registration error is the presence of hypoperfusion defects, which was evaluated in this study with simulated lesions. The brain perfusion images measured by 99mTc-HMPAO SPECT from 21 patients with probable Alzheimer's disease and 35 control subjects were retrospectively analyzed. An automatic segmentation method was developed to remove external activity. Three registration methods, robust least squares, normalized mutual information (NMI), and count difference were implemented and the effects of simulated defects were compared. The tested registration methods required segmentation of the cerebrum from external activity, and the automatic and manual methods differed by a three-dimensional displacement of 1.4+/-1.1 mm. NMI registration proved to be least adversely effected by simulated defects with 3 mm average displacement caused by severe defects. The error in quantifying the patient-template parietal ratio due to misregistration was 2.0% for large defects (70% hypoperfusion) and 0.5% for smaller defects (85% hypoperfusion).

  12. Linear intensity normalization of FP-CIT SPECT brain images using the α-stable distribution.

    PubMed

    Salas-Gonzalez, Diego; Górriz, Juan M; Ramírez, Javier; Illán, Ignacio A; Lang, Elmar W

    2013-01-15

    In this work, a linear procedure to perform the intensity normalization of FP-CIT SPECT brain images is presented. This proposed methodology is based on the fact that the histogram of intensity values can be fitted accurately using a positive skewed α-stable distribution. Then, the predicted α-stable parameters and the location-scale property are used to linearly transform the intensity values in each voxel. This transformation is performed such that the new histograms in each image have a pre-specified α-stable distribution with desired location and dispersion values. The proposed methodology is compared with a similar approach assuming Gaussian distribution and the widely used specific-to-nonspecific ratio. In this work, we show that the linear normalization method using the α-stable distribution outperforms those existing methods. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Clinical Evaluation of Brain Perfusion SPECT with Brodmann Areas Mapping in Early Diagnosis of Alzheimer's Disease.

    PubMed

    Valotassiou, Varvara; Papatriantafyllou, John; Sifakis, Nikolaos; Tzavara, Chara; Tsougos, Ioannis; Psimadas, Dimitrios; Fezoulidis, Ioannis; Kapsalaki, Eftychia; Hadjigeorgiou, George; Georgoulias, Panagiotis

    2015-01-01

    Early diagnosis of Alzheimer's disease (AD) based on clinical criteria alone may be problematic, while current and future treatments should be administered earlier in order to be more effective. Thus, various disease biomarkers could be used for early detection of AD. We evaluated brain perfusion with 99mTc-HMPAO single photon emission computed tomography (SPECT) and Brodmann areas (BAs) mapping in mild AD using an automated software (NeuroGam) for the semi-quantitative evaluation of perfusion in BAs and the comparison with the software's normal database. We studied 34 consecutive patients with mild AD: 9 men, 25 women, mean age 70.9 ± 8.1 years, mean Mini-Mental State Examination 22.6 ± 2.5. BAs 25L, 25R, 38L, 38R, 28L, 28R, 36L, and 36R had the lower mean perfusion values, while BAs 31L, 31R, 19R, 18L, 18R, 17L, and 17R had the higher mean values. Compared with healthy subjects of the same age, perfusion values in BAs 25L, 25R, 28R, 28L, 36L, and 36R had the greatest deviations from the healthy sample, while the lowest deviations were found in BAs 32L, 32R, 19R, 24L, 17L, 17R, 18L, and 18R. A percentage of ≥94% of patients had perfusion values more than -2SDs below the mean of healthy subjects in BAs 38R, 38L, 36L, 36R, 23L, 23R, 22L, 44L, 28L, 28R, 25L, and 25R. The corresponding proportion was less than 38% for BAs 11L, 19R, 32L, 32R, 18L, 18R, 24L, and 17R. In conclusion, brain SPECT studies with automated perfusion mapping could be useful as an ancillary tool in daily practice, revealing perfusion impairments in early AD.

  14. Including anatomical and functional information in MC simulation of PET and SPECT brain studies. Brain-VISET: a voxel-based iterative method.

    PubMed

    Marti-Fuster, Berta; Esteban, Oscar; Thielemans, Kris; Setoain, Xavier; Santos, Andres; Ros, Domenec; Pavia, Javier

    2014-10-01

    Monte Carlo (MC) simulation provides a flexible and robust framework to efficiently evaluate and optimize image processing methods in emission tomography. In this work we present Brain-VISET (Voxel-based Iterative Simulation for Emission Tomography), a method that aims to simulate realistic [ (99m) Tc]-SPECT and [ (18) F]-PET brain databases by including anatomical and functional information. To this end, activity and attenuation maps generated using high-resolution anatomical images from patients were used as input maps in a MC projector to simulate SPECT or PET sinograms. The reconstructed images were compared with the corresponding real SPECT or PET studies in an iterative process where the activity inputs maps were being modified at each iteration. Datasets of 30 refractory epileptic patients were used to assess the new method. Each set consisted of structural images (MRI and CT) and functional studies (SPECT and PET), thereby allowing the inclusion of anatomical and functional variability in the simulation input models. SPECT and PET sinograms were obtained using the SimSET package and were reconstructed with the same protocols as those employed for the clinical studies. The convergence of Brain-VISET was evaluated by studying the behavior throughout iterations of the correlation coefficient, the quotient image histogram and a ROI analysis comparing simulated with real studies. The realism of generated maps was also evaluated. Our findings show that Brain-VISET is able to generate realistic SPECT and PET studies and that four iterations is a suitable number of iterations to guarantee a good agreement between simulated and real studies.

  15. Impact of extraneous mispositioned events on motion-corrected brain SPECT images of freely moving animals.

    PubMed

    Angelis, Georgios I; Ryder, William J; Bashar, Rezaul; Fulton, Roger R; Meikle, Steven R

    2014-09-01

    Single photon emission computed tomography (SPECT) brain imaging of freely moving small animals would allow a wide range of important neurological processes and behaviors to be studied, which are normally inhibited by anesthetic drugs or precluded due to the animal being restrained. While rigid body motion of the head can be tracked and accounted for in the reconstruction, activity in the torso may confound brain measurements, especially since motion of the torso is more complex (i.e., nonrigid) and not well correlated with that of the head. The authors investigated the impact of mispositioned events and attenuation due to the torso on the accuracy of motion corrected brain images of freely moving mice. Monte Carlo simulations of a realistic voxelized mouse phantom and a dual compartment phantom were performed. Each phantom comprised a target and an extraneous compartment which were able to move independently of each other. Motion correction was performed based on the known motion of the target compartment only. Two SPECT camera geometries were investigated: a rotating single head detector and a stationary full ring detector. The effects of motion, detector geometry, and energy of the emitted photons (hence, attenuation) on bias and noise in reconstructed brain regions were evaluated. The authors observed two main sources of bias: (a) motion-related inconsistencies in the projection data and (b) the mismatch between attenuation and emission. Both effects are caused by the assumption that the orientation of the torso is difficult to track and model, and therefore cannot be conveniently corrected for. The motion induced bias in some regions was up to 12% when no attenuation effects were considered, while it reached 40% when also combined with attenuation related inconsistencies. The detector geometry (i.e., rotating vs full ring) has a big impact on the accuracy of the reconstructed images, with the full ring detector being more advantageous. Motion

  16. Impact of extraneous mispositioned events on motion-corrected brain SPECT images of freely moving animals

    SciTech Connect

    Angelis, Georgios I. Ryder, William J.; Bashar, Rezaul; Meikle, Steven R.; Fulton, Roger R.

    2014-09-15

    Purpose: Single photon emission computed tomography (SPECT) brain imaging of freely moving small animals would allow a wide range of important neurological processes and behaviors to be studied, which are normally inhibited by anesthetic drugs or precluded due to the animal being restrained. While rigid body motion of the head can be tracked and accounted for in the reconstruction, activity in the torso may confound brain measurements, especially since motion of the torso is more complex (i.e., nonrigid) and not well correlated with that of the head. The authors investigated the impact of mispositioned events and attenuation due to the torso on the accuracy of motion corrected brain images of freely moving mice. Methods: Monte Carlo simulations of a realistic voxelized mouse phantom and a dual compartment phantom were performed. Each phantom comprised a target and an extraneous compartment which were able to move independently of each other. Motion correction was performed based on the known motion of the target compartment only. Two SPECT camera geometries were investigated: a rotating single head detector and a stationary full ring detector. The effects of motion, detector geometry, and energy of the emitted photons (hence, attenuation) on bias and noise in reconstructed brain regions were evaluated. Results: The authors observed two main sources of bias: (a) motion-related inconsistencies in the projection data and (b) the mismatch between attenuation and emission. Both effects are caused by the assumption that the orientation of the torso is difficult to track and model, and therefore cannot be conveniently corrected for. The motion induced bias in some regions was up to 12% when no attenuation effects were considered, while it reached 40% when also combined with attenuation related inconsistencies. The detector geometry (i.e., rotating vs full ring) has a big impact on the accuracy of the reconstructed images, with the full ring detector being more

  17. Brain SPECT and Neuropsychological Examination in Patients with a History of Minor Craniocerebral Trauma Nine Years after Head Injury.

    PubMed

    Dawid, S; Marks, W; Lasek, J; Witkowski, Z; Goŀąbek-Dropiewska, K; Sitek, E J; Wieczorek, D; Brockhuis, B; Lass, P

    2010-03-01

    Focal perfusion deficits disclosed by single photon emission computerized tomography (SPECT) show more diffuse brain dysfunction than computed tomography (CT) examinations in case of head trauma. The aim of the study was to evaluate SPECT as an enhancing and complementary diagnostic method in patients after minor craniocerebral trauma (mCCT) and establish a possible correlation between clinical symptoms and disturbances of cerebral blood flow (CBF). SPECT examination and neuropsychological assessment was performed in seven patients about nine years after head injury, scoring 13-15 points on the Glasgow COMA SCALE and without evidence of structural brain damage. Neuropsychological assessment addressed global cognitive status, verbal and visual memory, working memory, object and space perception, executive function, self-assessment of memory, mood and health-related complaints. A direct relationship was shown between mCCT and the observed CBF disorders, and between the CBF disorders and cognitive dysfunction. Because of its sensitivity, SPECT, should be regarded as a method complementary to CT in mCCT.

  18. Improved outcomes using brain SPECT-guided treatment versus treatment-as-usual in community psychiatric outpatients: a retrospective case-control study.

    PubMed

    Thornton, John F; Schneider, Howard; McLean, Mary K; van Lierop, Muriel J; Tarzwell, Robert

    2014-01-01

    Brain single-photon emission computed tomography (SPECT) scans indirectly show functional activity via measurement of regional cerebral blood flow. Thirty patients at a community-based psychiatric clinic underwent brain SPECT scans. Changes in scoring of before-treatment and after-treatment scans correlated well with changes in patient Global Assessment of Functioning (GAF) scores before treatment and after treatment. Patients were retrospectively matched with controls with similar diagnoses and pretreatment GAF scores, and those who underwent SPECT-guided treatment improved significantly more than the control patients.

  19. A Computer-Aided Analysis Method of SPECT Brain Images for Quantitative Treatment Monitoring: Performance Evaluations and Clinical Applications.

    PubMed

    Zheng, Xiujuan; Wei, Wentao; Huang, Qiu; Song, Shaoli; Wan, Jieqing; Huang, Gang

    2017-01-01

    The objective and quantitative analysis of longitudinal single photon emission computed tomography (SPECT) images are significant for the treatment monitoring of brain disorders. Therefore, a computer aided analysis (CAA) method is introduced to extract a change-rate map (CRM) as a parametric image for quantifying the changes of regional cerebral blood flow (rCBF) in longitudinal SPECT brain images. The performances of the CAA-CRM approach in treatment monitoring are evaluated by the computer simulations and clinical applications. The results of computer simulations show that the derived CRMs have high similarities with their ground truths when the lesion size is larger than system spatial resolution and the change rate is higher than 20%. In clinical applications, the CAA-CRM approach is used to assess the treatment of 50 patients with brain ischemia. The results demonstrate that CAA-CRM approach has a 93.4% accuracy of recovered region's localization. Moreover, the quantitative indexes of recovered regions derived from CRM are all significantly different among the groups and highly correlated with the experienced clinical diagnosis. In conclusion, the proposed CAA-CRM approach provides a convenient solution to generate a parametric image and derive the quantitative indexes from the longitudinal SPECT brain images for treatment monitoring.

  20. A Computer-Aided Analysis Method of SPECT Brain Images for Quantitative Treatment Monitoring: Performance Evaluations and Clinical Applications

    PubMed Central

    Wei, Wentao; Huang, Qiu; Wan, Jieqing; Huang, Gang

    2017-01-01

    The objective and quantitative analysis of longitudinal single photon emission computed tomography (SPECT) images are significant for the treatment monitoring of brain disorders. Therefore, a computer aided analysis (CAA) method is introduced to extract a change-rate map (CRM) as a parametric image for quantifying the changes of regional cerebral blood flow (rCBF) in longitudinal SPECT brain images. The performances of the CAA-CRM approach in treatment monitoring are evaluated by the computer simulations and clinical applications. The results of computer simulations show that the derived CRMs have high similarities with their ground truths when the lesion size is larger than system spatial resolution and the change rate is higher than 20%. In clinical applications, the CAA-CRM approach is used to assess the treatment of 50 patients with brain ischemia. The results demonstrate that CAA-CRM approach has a 93.4% accuracy of recovered region's localization. Moreover, the quantitative indexes of recovered regions derived from CRM are all significantly different among the groups and highly correlated with the experienced clinical diagnosis. In conclusion, the proposed CAA-CRM approach provides a convenient solution to generate a parametric image and derive the quantitative indexes from the longitudinal SPECT brain images for treatment monitoring. PMID:28251150

  1. Corneal Dose Reduction Using a Bismuth-Coated Latex Shield over the Eyes During Brain SPECT/CT.

    PubMed

    Matsutomo, Norikazu; Fukunaga, Masaaki; Onishi, Hideo; Yamamoto, Tomoaki

    2017-09-01

    This study aimed to determine whether a bismuth-coated latex shield (B-shield) could protect the eyes during brain SPECT/CT. Methods: A shield containing the heavy metal bismuth (equivalent to a 0.15-mm-thick lead shield) was placed over a cylindric phantom and the eyes of a 3-dimensional brain phantom filled with (99m)Tc solution. Subsequently, phantoms with and without the B-shield were compared using SPECT/CT. The CT parameters were 30-200 mA and 130 kV. The dose reduction achieved by the B-shield was measured using a pencil-shaped ionization chamber. The protective effects of the B-shield were determined by evaluating relative radioactivity concentration as well as artifacts (changes in CT number), linear attenuation coefficients, and coefficients of variation on SPECT images. Results: The radiation doses with and without the B-shield were 0.14-0.77 and 0.36-1.93 mGy, respectively, and the B-shield decreased the average radiation dose by about 60%. The B-shield also increased the mean CT number, but only at locations just beneath the surface of the phantom. Streaks of higher density near the underside of the B-shield indicated beam hardening. Linear attenuation coefficients and the coefficients of variation did not significantly differ between phantoms with and without the B-shield, and the relative (99m)Tc radioactivity concentrations were not affected. Conclusion: The B-shield decreased the radiation dose without affecting estimated attenuation correction or radioactivity concentrations. Although surface artifacts increased with the B-shield, the quality of the SPECT images was acceptable. B-shields can help protect pediatric patients and patients with eye diseases who undergo SPECT imaging. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

  2. Old wine in new bottles: validating the clinical utility of SPECT in predicting cognitive performance in mild traumatic brain injury.

    PubMed

    Romero, Kristoffer; Lobaugh, Nancy J; Black, Sandra E; Ehrlich, Lisa; Feinstein, Anthony

    2015-01-30

    The neural underpinnings of cognitive dysfunction in mild traumatic brain injury (TBI) are not fully understood. Consequently, patient prognosis using existing clinical imaging is somewhat imprecise. Single photon emission computed tomography (SPECT) is a frequently employed investigation in this population, notwithstanding uncertainty over the clinical utility of the data obtained. In this study, subjects with mild TBI underwent (99m)Tc-ECD SPECT scanning, and were administered a brief battery of cognitive tests and self-report symptom scales of concussion and emotional distress. Testing took place 2 weeks (n=84) and 1 year (n=49) post-injury. Multivariate analysis (i.e., partial least squares analysis) revealed that frontal perfusion in right superior frontal and middle frontal gyri predicted poorer performance on the Stroop test, an index of executive function, both at initial and follow-up testing. Conversely, SPECT scans categorized as normal or abnormal by radiologists did not differentiate cognitively impaired from intact subjects. These results demonstrate the clinical utility of SPECT in mild TBI, but only when data are subjected to blood flow quantification analysis.

  3. Neuroreceptor imaging with SPECT.

    PubMed

    Innis, R B

    1992-11-01

    Single photon emission computed tomography (SPECT) imaging can provide useful measurements of brain receptors and endogenous neurotransmitters and may have significant experimental and clinical applications. This presentation reviews the use of SPECT for neuroreceptor imaging. Studies of receptors for benzodiazepines, dopamine D2 agents, and dopamine reuptake sites will be used to exemplify the capabilities of SPECT. Tracers labeled with the radioisotope 125I have high affinity, high brain uptake, and high ratios of specific to nonspecific binding. Imaging studies of human and nonhuman primate brain will be presented, and the potential clinical applicability of these agents will be discussed.

  4. Collimator selection for SPECT brain imaging: the advantage of high resolution

    SciTech Connect

    Mueller, S.P.; Polak, J.F.; Kijewski, M.F.; Holman, B.L.

    1986-11-01

    We compared a prototype long-bore (LB) high-resolution collimator with a low-energy, general-purpose collimator (LEGP) using 99mTc and /sup 123/I. The LB collimator provided a 56% improvement in tomographic resolution (autocorrelation width) over the LEGP for 99mTc; for /sup 123/I, the gain was 79%, providing substantially improved contrast for small structures. The sensitivity of the LB collimator, however, is only 32% of that of the LEGP. The imaging tasks to be performed on (/sup 123/I)IMP brain scans involve localization and discrimination of small, high-contrast brain structures and detection of abnormalities in shape, size, or uptake, rather than simple detection of lesions. Observer performance in such higher-order imaging tasks is known to depend on high spatial resolution, even at the cost of sensitivity. Patient studies confirmed that, for resolution-limited tasks, the increase in resolution outweighs the increased noise due to a loss in sensitivity. When the tomographic resolution of the LB collimator was degraded by smoothing to that of the LEGP, the noise in the LB images was lower than that of the LEGP by a factor of 2.9 for the same imaging time, demonstrating the advantage of high-resolution detectors and a smooth reconstruction filter over low-resolution detectors without smoothing. Therefore, collimators designed for high resolution, even at substantial cost in sensitivity, are expected to yield significant improvements for brain SPECT. Geometric calculations show that commercially available low-energy, high-resolution cast collimators promise to meet these requirements.

  5. Can brain thallium 201 SPECT substitute for F-18-FDG PET in detecting recurrent brain tumor in the presence of radiation necrosis; correlation with biopsy/surgery results

    SciTech Connect

    Antar, M.A.; Barnett, G.H.; McIntyre, W.J.

    1994-05-01

    F-18-FDG PET man has been largely successful in differentiating between radiation necrosis and recurrent brain tumors. Because of the expense and unavailability of PET scanners in most clinical centers, Tl-201 SPECT scan may offer an alternative. Therefore, we have evaluated both techniques in 18 patients (13 men and 5 women) whose ages range from 28 to 74 year old. Eleven patients had glioblastoma multiformi and 4 patients high grade astrocytoma and 3 patient meningiosarcoma. All patients received radiation therapy (5500-6000 Rad) and 13 patients received also chemotherapy. PET scan was performed 40-60 min. after 5-10 mCi of F-18 FDG (i.v.) and SPECT 30 min. after 4.6 mCi of Tl-201 chloride (i.v.). Severe FDG hypometabolism was evident in the irradiated regions, in all patients. Evidence of tumor recurrence was seen in 15 patients by both FDG PET and Thallium 201 SPECT. The ratio of peak pixel uptake of suspected tumor to that of normal cortex for FDG ranged from 0.67 to 1.5 with a mean of 1.02. The ratio of peak pixel uptake of thallium 201 in the suspected lesion to that of the contralateral scalp area ranges from 0.8 to 1.9 with mean of 1.1. There was concordance between the findings of PET and SPECT in 16/18 patients. However, the volume of involvement differs in these patients; most likely secondary to different mechanisms of uptake and both studies may complement each other. Subsequent biopsy/surgery in 11 patients confirmed tumor recurrence in 10 out of 11 patients. The findings suggest that thallium 201 brain SPECT scan can provide similar (but not identical) information regarding brain tumor recurrence in these patients.

  6. High-resolution single photon planar and spect imaging of brain and neck employing a system of two co-registered opposed gamma imaging heads

    DOEpatents

    Majewski, Stanislaw [Yorktown, VA; Proffitt, James [Newport News, VA

    2011-12-06

    A compact, mobile, dedicated SPECT brain imager that can be easily moved to the patient to provide in-situ imaging, especially when the patient cannot be moved to the Nuclear Medicine imaging center. As a result of the widespread availability of single photon labeled biomarkers, the SPECT brain imager can be used in many locations, including remote locations away from medical centers. The SPECT imager improves the detection of gamma emission from the patient's head and neck area with a large field of view. Two identical lightweight gamma imaging detector heads are mounted to a rotating gantry and precisely mechanically co-registered to each other at 180 degrees. A unique imaging algorithm combines the co-registered images from the detector heads and provides several SPECT tomographic reconstructions of the imaged object thereby improving the diagnostic quality especially in the case of imaging requiring higher spatial resolution and sensitivity at the same time.

  7. High-sensitivity brain SPECT system using cadmium telluride (CdTe) semiconductor detector and 4-pixel matched collimator.

    PubMed

    Suzuki, Atsuro; Takeuchi, Wataru; Ishitsu, Takafumi; Tsuchiya, Katsutoshi; Morimoto, Yuichi; Ueno, Yuichiro; Kobashi, Keiji; Kubo, Naoki; Shiga, Tohru; Tamaki, Nagara

    2013-11-07

    For high-sensitivity brain imaging, we have developed a two-head single-photon emission computed tomography (SPECT) system using a CdTe semiconductor detector and 4-pixel matched collimator (4-PMC). The term, '4-PMC' indicates that the collimator hole size is matched to a 2 × 2 array of detector pixels. By contrast, a 1-pixel matched collimator (1-PMC) is defined as a collimator whose hole size is matched to one detector pixel. The performance of the higher-sensitivity 4-PMC was experimentally compared with that of the 1-PMC. The sensitivities of the 1-PMC and 4-PMC were 70 cps/MBq/head and 220 cps/MBq/head, respectively. The SPECT system using the 4-PMC provides superior image resolution in cold and hot rods phantom with the same activity and scan time to that of the 1-PMC. In addition, with half the usual scan time the 4-PMC provides comparable image quality to that of the 1-PMC. Furthermore, (99m)Tc-ECD brain perfusion images of healthy volunteers obtained using the 4-PMC demonstrated acceptable image quality for clinical diagnosis. In conclusion, our CdTe SPECT system equipped with the higher-sensitivity 4-PMC can provide better spatial resolution than the 1-PMC either in half the imaging time with the same administered activity, or alternatively, in the same imaging time with half the activity.

  8. High-sensitivity brain SPECT system using cadmium telluride (CdTe) semiconductor detector and 4-pixel matched collimator

    NASA Astrophysics Data System (ADS)

    Suzuki, Atsuro; Takeuchi, Wataru; Ishitsu, Takafumi; Tsuchiya, Katsutoshi; Morimoto, Yuichi; Ueno, Yuichiro; Kobashi, Keiji; Kubo, Naoki; Shiga, Tohru; Tamaki, Nagara

    2013-11-01

    For high-sensitivity brain imaging, we have developed a two-head single-photon emission computed tomography (SPECT) system using a CdTe semiconductor detector and 4-pixel matched collimator (4-PMC). The term, ‘4-PMC’ indicates that the collimator hole size is matched to a 2 × 2 array of detector pixels. By contrast, a 1-pixel matched collimator (1-PMC) is defined as a collimator whose hole size is matched to one detector pixel. The performance of the higher-sensitivity 4-PMC was experimentally compared with that of the 1-PMC. The sensitivities of the 1-PMC and 4-PMC were 70 cps/MBq/head and 220 cps/MBq/head, respectively. The SPECT system using the 4-PMC provides superior image resolution in cold and hot rods phantom with the same activity and scan time to that of the 1-PMC. In addition, with half the usual scan time the 4-PMC provides comparable image quality to that of the 1-PMC. Furthermore, 99mTc-ECD brain perfusion images of healthy volunteers obtained using the 4-PMC demonstrated acceptable image quality for clinical diagnosis. In conclusion, our CdTe SPECT system equipped with the higher-sensitivity 4-PMC can provide better spatial resolution than the 1-PMC either in half the imaging time with the same administered activity, or alternatively, in the same imaging time with half the activity.

  9. Use of neural networks in brain SPECT to diagnose Alzheimer's disease.

    PubMed

    Page, M P; Howard, R J; O'Brien, J T; Buxton-Thomas, M S; Pickering, A D

    1996-02-01

    The usefulness of artificial neural networks in the classification of 99mTc-HMPAO SPECT axial brain scans was investigated in a study group of Alzheimer's disease patients and age-matched normal subjects. The cortical circumferential profiling (CCP) technique was used to extract information regarding patterns of cortical perfusion. Traditional analysis of the CCP data, taken from slices at the level of the basal ganglia, indicated significant perfusion deficits for Alzheimer's disease patients relative to normals, particularly in the left temporo-parietal and left posterior frontal areas of the cortex. The compressed profiles were then used to train a neural-network classifier, the performance of which was compared with that of a number of more traditional statistical (discriminant function) techniques and that of two expert viewers. The optimal classification performance of the neural network (ROC area = 0.91) was better than that of the alternative statistical techniques (max. ROC area = 0.85) and that of the expert viewers (max. ROC area = 0.79). The CCP produces perfusion profiles which are well suited to automated classification methods, particularly those employing neural networks. The technique has the potential for wide application.

  10. NMF-Based Analysis of SPECT Brain Images for the Diagnosis of Alzheimer's Disease

    NASA Astrophysics Data System (ADS)

    Padilla, Pablo; Górriz, Juan-Manuel; Ramírez, Javier; Lang, Elmar; Chaves, Rosa; Segovia, Fermin; Álvarez, Ignacio; Salas-González, Diego; López, Miriam

    This paper offers a computer-aided diagnosis (CAD) technique for early diagnosis of Alzheimer's disease (AD) by means of single photon emission computed tomography (SPECT) image classification. The SPECT database for different patients is analyzed by applying the Fisher discriminant ratio (FDR) and non-negative matrix factorization (NMF) for the selection and extraction of the most significative features of each patient SPECT data, in order to reduce the large dimensionality of the input data and the problem of the curse of dimensionality, extracting score features. The NMF-transformed set of data, with reduced number of features, is classified by means of support vector machines (SVM) classification. The proposed NMF+SVM method yields up to 94% classification accuracy, thus becoming an accurate method for SPECT image classification. For the sake of completeness, comparison between conventional PCA+SVM method and the proposed method is also provided.

  11. Brain areas involved in acupuncture needling sensation of de qi: a single-photon emission computed tomography (SPECT) study.

    PubMed

    Chen, Jia-Rong; Li, Gan-Long; Zhang, Gui-Feng; Huang, Yong; Wang, Shu-Xia; Lu, Na

    2012-12-01

    De qi is a sensory response elicited by acupuncture stimulation. According to traditional Chinese medicine (TCM), de qi is essential for clinical efficacy. However, the understanding of the neurobiological basis of de qi is still limited. To investigate the relationship between brain activation and de qi by taking a single-photon emission computed tomography (SPECT) scan while applying acupuncture at TE5. A total of 24 volunteers were randomly divided into 4 groups, and received verum or sham acupuncture at true acupuncture point TE5 or a nearby sham point according to grouping. All subjects then received a (99m)Tc-ethylcysteinate dimer (ECD) SPECT scan. All six subjects in the verum acupuncture at true acupuncture point group experienced de qi sensation; in contrast, all six subjects in the sham acupuncture at the sham point group responded with nothing other than non-sensation. Compared to the scan results from subjects who experienced non-sensation, SPECT scans from subjects with de qi sensation demonstrated significant activated points mainly located in brodmann areas 6, 8, 19, 21, 28, 33, 35, 37, 47, the parahippocampal gyrus, lentiform nucleus, claustrum and red nucleus; deactivated points were seen in brodmann areas 9 and 25. Verum acupuncture at true acupuncture points is more likely to elicit de qi sensation. De qi sensations mainly resulted in brain area activations, but not deactivations. These brain areas are related to the curative effect of Te5. The acupuncture needle sensations of de qi and sharp pain are associated with different patterns of activations and deactivations in the brain.

  12. Statistical parametric mapping demonstrates asymmetric uptake with Tc-99m ECD and Tc-99m HMPAO SPECT in normal brain

    PubMed Central

    Brinkmann, Benjamin H; Jones, David T; Stead, Matt; Kazemi, Noojan; O'Brien, Terence J; So, Elson L; Blumenfeld, Hal; Mullan, Brian P; Worrell, Gregory A

    2012-01-01

    Tc-99m ethyl cysteinate diethylester (ECD) and Tc-99m hexamethyl propylene amine oxime (HMPAO) are commonly used for single-photon emission computed tomography (SPECT) studies of a variety of neurologic disorders. Although these tracers have been very helpful in diagnosing and guiding treatment of neurologic disease, data describing the distribution and laterality of these tracers in normal resting brain are limited. Advances in quantitative functional imaging have demonstrated the value of using resting studies from control populations as a baseline to account for physiologic fluctuations in cerebral perfusion. Here, we report results from 30 resting Tc-99m ECD SPECT scans and 14 resting Tc-99m HMPAO scans of normal volunteers with no history of neurologic disease. Scans were analyzed with regions of interest and with statistical parametric mapping, with comparisons performed laterally (left vs. right), as well as for age, gender, and handedness. The results show regions of significant asymmetry in the normal controls affecting widespread areas in the cerebral hemispheres, but most marked in superior parietotemporal region and frontal lobes. The results have important implications for the use of normal control SPECT images in the evaluation of patients with neurologic disease. PMID:21934696

  13. CT-based attenuation and scatter correction compared with uniform attenuation correction in brain perfusion SPECT imaging for dementia

    NASA Astrophysics Data System (ADS)

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

    2015-09-01

    This study investigated if the appearance and diagnostic accuracy of HMPAO brain perfusion SPECT images could be improved by using CT-based attenuation and scatter correction compared with the uniform attenuation correction method. A cohort of subjects who were clinically categorized as Alzheimer’s Disease (n=38 ), Dementia with Lewy Bodies (n=29 ) or healthy normal controls (n=30 ), underwent SPECT imaging with Tc-99m HMPAO and a separate CT scan. The SPECT images were processed using: (a) correction map derived from the subject’s CT scan or (b) the Chang uniform approximation for correction or (c) no attenuation correction. Images were visually inspected. The ratios between key regions of interest known to be affected or spared in each condition were calculated for each correction method, and the differences between these ratios were evaluated. The images produced using the different corrections were noted to be visually different. However, ROI analysis found similar statistically significant differences between control and dementia groups and between AD and DLB groups regardless of the correction map used. We did not identify an improvement in diagnostic accuracy in images which were corrected using CT-based attenuation and scatter correction, compared with those corrected using a uniform correction map.

  14. Correlation between clinical severity of central nervous system (CNS) lupus and findings on single photon emission computed tomographic (SPECT) images of the brain; preliminary results

    SciTech Connect

    Silverman, I.E.; Zeit, R.M.; Von Feldt, J.M.

    1994-05-01

    Systemic Lupus Erythematosis (SLE) commonly causes significant neuropsychiatric disorders. The purpose of this study was to review the brain SPECT studies of SLE patients with clinical evidence of CNS involvement and determine whether there is a correlation between the findings on SPECT images and the clinical manifestations of this serious phase of the disease. We enrolled 19 SLE patients and 12 normal controls in this study. The level of each patient`s disease activity was determined by the SLE Disease Activity Index (SLEDAI), an established method of scoring disease severity which is heavily weighted toward neuropsychiatric symptomatology, for 15 of the 19 SLE patients. The SLEDAI was calculated within a 10 day window of the date when the SPECT scan was obtained. SPECT scans were performed 30 minutes following the intravenous administration of 99mTc-HMPAO. Results are discussed.

  15. Performance of a novel collimator for high-sensitivity brain SPECT

    SciTech Connect

    El Fakhri, Georges; Ouyang Jinsong; Zimmerman, Robert E.; Fischman, Alan J.; Kijewski, Marie Foley

    2006-01-15

    We assessed improvements in performance in detection and estimation tasks due to a novel brain single photon computed tomography collimator. Data were acquired on the CeraSPECT{sup TM} scanner using both new and standard collimators. The new variable focusing collimator SensOgrade{sup TM} samples the projections unequally, with central regions more heavily represented, to compensate for attenuation of counts from central brain structures. Furthermore, it utilizes more of the cylindrical crystal surface. Two phantom studies were performed. The first phantom was a 21-cm-diameter cylindrical background containing nine spheres ranging from 0.5 to 5 cm{sup 3} in volume. {sup 99m}Tc sphere to background activity ratio was 10:1. Twenty-nine 10-min datasets were acquired with each collimator. The second phantom was the Radiology Support Devices (Long Beach, CA) striatal phantom with striatal-background ratios of 10:1 on the left and 5:1 on the right. Twenty-nine 4-min datasets were acquired with each collimator. Perfusion imaging using {sup 99m}Tc-HMPAO was also performed in three healthy volunteers using both collimators under identical simulations. Projections were reconstructed by filtered backprojection with an unwindowed ramp filter. The nonprewhitening matched filter signal-to-noise ratio (NPW-SNR) was computed as a surrogate for human performance in detecting spherical lesions. Sphere activity concentration, radius, and location coordinates were simultaneously estimated by fitting images to an assumed model using an iterative nonlinear algorithm. Resolution recovery was implicit in the estimation procedure, as the point spread function was incorporated into the model. NPW-SNR for sphere detection was 1.5 to 2 times greater with the new collimator; for the striatal phantom the improvement in SNR was 54%. The SNR for estimating sphere activity concentration improved by 46 to 89 % for spheres located more than 5 cm from the phantom center. Images acquired with the

  16. Performance of a novel collimator for high-sensitivity brain SPECT.

    PubMed

    El Fakhri, Georges; Ouyang, Jinsong; Zimmerman, Robert E; Fischman, Alan J; Kijewski, Marie Foley

    2006-01-01

    We assessed improvements in performance in detection and estimation tasks due to a novel brain single photon computed tomography collimator. Data were acquired on the CeraSPECT scanner using both new and standard collimators. The new variable focusing collimator SensOgrade samples the projections unequally, with central regions more heavily represented, to compensate for attenuation of counts from central brain structures. Furthermore, it utilizes more of the cylindrical crystal surface. Two phantom studies were performed. The first phantom was a 21-cm-diameter cylindrical background containing nine spheres ranging from 0.5 to 5 cm3 in volume. 99mTc sphere to background activity ratio was 10:1. Twenty-nine 10-min datasets were acquired with each collimator. The second phantom was the Radiology Support Devices (Long Beach, CA) striatal phantom with striatal-background ratios of 10:1 on the left and 5:1 on the right. Twenty-nine 4-min datasets were acquired with each collimator. Perfusion imaging using 99mTc-HMPAO was also performed in three healthy volunteers using both collimators under identical simulations. Projections were reconstructed by filtered backprojection with an unwindowed ramp filter. The nonprewhitening matched filter signal-to-noise ratio (NPW-SNR) was computed as a surrogate for human performance in detecting spherical lesions. Sphere activity concentration, radius, and location coordinates were simultaneously estimated by fitting images to an assumed model using an iterative nonlinear algorithm. Resolution recovery was implicit in the estimation procedure, as the point spread function was incorporated into the model. NPW-SNR for sphere detection was 1.5 to 2 times greater with the new collimator; for the striatal phantom the improvement in SNR was 54%. The SNR for estimating sphere activity concentration improved by 46 to 89% for spheres located more than 5 cm from the phantom center. Images acquired with the standard collimator were too noisy in

  17. SU-C-9A-07: Fabrication and Calibration of a Novel High-Sensitivity Collimator for Brain SPECT Imaging

    SciTech Connect

    Park, M; Kijewski, M; Horky, L; Moore, S; Keijzers, M; Keijzers, R; Kalfin, L; Crough, J; Goswami, M

    2014-06-01

    Purpose: We have designed a novel collimator for brain SPECT imaging that yields greatly increased sensitivity near the center of the brain without loss of resolution. The collimator was manufactured and initial evaluation has been completed. Methods: The collimator was time-consuming and challenging to build. Because our desired hole pattern required substantial variations in hole angle, we designed two supporting plates to securely position about 34,000 hexagonal, slightly tapered, 75-mm long steel pins. The holes in the plates were modeled to yield the desired focal length, hole length and septal thickness. Molten lead was poured in between the plates, and all pins were removed after cooling. The sensitivity gain compared to a fan-beam collimator was measured using a point source placed along the central ray at several distances from the collimator face. Visual inspection of the holes was not possible as the collimator was sealed so it could be safely mounted on a SPECT system. Therefore, we prepared a 2D array of 768, ∼48μCi Tc-99m point sources, separated by 1.6 cm. The array was imaged for 10 minutes at 4 shifted locations to reduce sampling distance to 8 mm. Results: The sensitivity of the novel cone-beam collimator varied with distance from the detector face; it was higher than that of the fan-beam collimator by factors ranging from 3 to 176. Examination of the projections of the 4×768 point sources revealed that fewer than 2% of the holes were fully or partially blocked, which indicates that the intensive manual fabrication process was very successful. Conclusion: We have designed and manufactured a novel collimator for brain SPECT imaging. As expected, the sensitivity is much higher than that of a fan-beam collimator. Because of differences between the manufactured collimator and its design, reconstruction of the data will require a measured system function.

  18. Quantification of GABAA receptors in the rat brain with [(123)I]Iomazenil SPECT from factor analysis-denoised images.

    PubMed

    Tsartsalis, Stergios; Moulin-Sallanon, Marcelle; Dumas, Noé; Tournier, Benjamin B; Ghezzi, Catherine; Charnay, Yves; Ginovart, Nathalie; Millet, Philippe

    2014-02-01

    In vivo imaging of GABAA receptors is essential for the comprehension of psychiatric disorders in which the GABAergic system is implicated. Small animal SPECT provides a modality for in vivo imaging of the GABAergic system in rodents using [(123)I]Iomazenil, an antagonist of the GABAA receptor. The goal of this work is to describe and evaluate different quantitative reference tissue methods that enable reliable binding potential (BP) estimations in the rat brain to be obtained. Five male Sprague-Dawley rats were used for [(123)I]Iomazenil brain SPECT scans. Binding parameters were obtained with a one-tissue compartment model (1TC), a constrained two-tissue compartment model (2TCc), the two-step Simplified Reference Tissue Model (SRTM2), Logan graphical analysis and analysis of delayed-activity images. In addition, we employed factor analysis (FA) to deal with noise in data. BPND obtained with SRTM2, Logan graphical analysis and delayed-activity analysis was highly correlated with BPF values obtained with 2TCc (r=0.954 and 0.945 respectively, p<0.0001). Equally significant correlations were found between values obtained with 2TCc and SRTM2 in raw and FA-denoised images (r=0.961 and 0.909 respectively, p<0.0001). Scans of at least 100min are required to obtain stable BPND values from raw images while scans of only 70min are sufficient from FA-denoised images. These images are also associated with significantly lower standard errors of 2TCc and SRTM2 BP values. Reference tissue methods such as SRTM2 and Logan graphical analysis can provide equally reliable BPND values from rat brain [(123)I]Iomazenil SPECT. Acquisitions, however, can be much less time-consuming either with analysis of delayed activity obtained from a 20-minute scan 50min after tracer injection or with FA-denoising of images. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. The evaluation of brain perfusion SPECT using an easy Z-score imaging system in the mild cognitive impairment subjects with brain amyloid-β deposition.

    PubMed

    Takemaru, Makoto; Kimura, Noriyuki; Abe, Yoshitake; Goto, Megumi; Matsubara, Etsuro

    2017-09-01

    The analysis of (99)mTc-ECD single-photon emission computed tomography (SPECT) images using the easy Z-score imaging system (eZIS) program is useful for the diagnosis of early AD in daily medical practice. However, it remains unclear whether eZIS analysis can identify the amnestic mild cognitive impairment (MCI) subjects with brain amyloid-β deposition. The aim of this study was to evaluate the usefulness of an eZIS analysis for predicting amnestic MCI subjects with brain amyloid β deposition. Twenty-three subjects with MCI (10 men and 13 women, mean age; 74.2 years) underwent brain perfusion SPECT and (11)C-Pittsburgh Compound B positron emission tomography (PiB-PET). MCI subjects were divided into PiB-positive and PiB-negative subgroups. SPECT data was analyzed using the Specific Volume of interest Analysis of the eZIS program. Three indicators (severity, extent, and ratio) were calculated automatically and compared between the two subgroups. Five of 12 (41.7%) subjects in the PiB-positive subgroup and three of 11 (27.3%) subjects in the PiB-negative subgroup showed the abnormal value for each indicator. The frequency of subjects with abnormal ratio values was significantly higher in the PiB-positive subgroup compared to the PiB-negative subgroup (p=0.02), whereas that of subjects with abnormal values in severity and extent did not differ among the two subgroups. In particular, all subjects in the PiB-negative subgroup showed normal ratio values. Moreover, the subjects with abnormal values on two indicators, including ratio, or on all three indicators, showed PiB-positive. The analysis of brain perfusion SPECT using an eZIS program cannot identify the amnestic MCI subjects with brain amyloid-β deposition. However, abnormal three indicators or normal ratio values may be helpful SPECT findings for predicting the results of PiB-PET in the amnestic MCI subjects. Copyright © 2017. Published by Elsevier B.V.

  20. Implementation of a fully 3D system model for brain SPECT with fan- beam-collimator OSEM reconstruction with 3D total variation regularization

    NASA Astrophysics Data System (ADS)

    Ye, Hongwei; Krol, Andrzej; Lipson, Edward D.; Lu, Yao; Xu, Yuesheng; Lee, Wei; Feiglin, David H.

    2007-03-01

    In order to improve tomographically reconstructed image quality, we have implemented a fully 3D reconstruction, using an ordered subsets expectation maximization (OSEM) algorithm for fan-beam collimator (FBC) SPECT, along with a volumetric system model-fan-volume system model (FVSM), a modified attenuation compensation, a 3D depth- and angle-dependent resolution and sensitivity correction, and a 3D total variation (TV) regularization. SPECT data were acquired in a 128x64 matrix, in 120 views with a circular orbit. The numerical Zubal brain phantom was used to simulate a FBC HMPAO Tc-99m brain SPECT scan, and a low noise and scatter-free projection dataset was obtained using the SimSET Monte Carlo package. A SPECT scan for a mini-Defrise phantom and brain HMPAO SPECT scans for five patients were acquired with a triple-head gamma camera (Triad 88) equipped with a low-energy high-resolution (LEHR) FBC. The reconstructed images, obtained using clinical filtered back projection (FBP), OSEM with a line-length system model (LLSM) and 3D TV regularization, and OSEM with FVSM and 3D TV regularization were quantitatively studied. Overall improvement in the image quality has been observed, including better axial and transaxial resolution, better integral uniformity, higher contrast-to-noise ration between the gray matter and the white matter, and better accuracy and lower bias in OSEM-FVSM, compared with OSEM-LLSM and clinical FBP.

  1. Hemodynamic and metabolic state of hyperfixation with 99mTc-HMPAO brain SPECT in subacute stroke.

    PubMed

    Cho, I; Hayashida, K; Imakita, S; Kume, N; Fukuchi, K

    2000-06-01

    By means of positron emission tomography (PET), we investigated the hemodynamic and metabolic state of the hyperfixation identified as the increased accumulation with 99mTc-d,l-hexamethylpropyleneamine oxime (HMPAO) by single photon emission computed tomography (SPECT) in patients with subacute stroke. We studied four patients with subacute stroke having hyperfixed areas evaluated with CBF, CMRO2, OEF and CBV by PET. The hyperfixation rate with 99mTc-HMPAO was obtained by comparing the surplus rate with standardized CBF. The OEF and CMRO2 values in the hyperfixed areas of 4 patients were significantly lower than those in normal 5 controls (p < 0.01), but CBF and CBV were almost the same in patients and normal controls, but the hyperfixation rate of 0.30 +/- 0.15 in 4 patients correlated well with CBV (r = 0.97, y = 11.75x + 0.42; p < 0.05). Hyperfixation with 99mTc-HMPAO in the infarct area revealing a mismatch between CMRO2 and CBF meant relative luxury perfusion. The hyperfixation rate determined by 99mTc-HMPAO brain SPECT correlated with CBV in the PET study. We can conclude that one of the main factors which caused hyperfixation was vasodilatation as well as the blood brain barrier disruption and the neovascularization.

  2. CT-Based Attenuation Correction in Brain SPECT/CT Can Improve the Lesion Detectability of Voxel-Based Statistical Analyses

    PubMed Central

    Kato, Hiroki; Shimosegawa, Eku; Fujino, Koichi; Hatazawa, Jun

    2016-01-01

    Background Integrated SPECT/CT enables non-uniform attenuation correction (AC) using built-in CT instead of the conventional uniform AC. The effect of CT-based AC on voxel-based statistical analyses of brain SPECT findings has not yet been clarified. Here, we assessed differences in the detectability of regional cerebral blood flow (CBF) reduction using SPECT voxel-based statistical analyses based on the two types of AC methods. Subjects and Methods N-isopropyl-p-[123I]iodoamphetamine (IMP) CBF SPECT images were acquired for all the subjects and were reconstructed using 3D-OSEM with two different AC methods: Chang’s method (Chang’s AC) and the CT-based AC method. A normal database was constructed for the analysis using SPECT findings obtained for 25 healthy normal volunteers. Voxel-based Z-statistics were also calculated for SPECT findings obtained for 15 patients with chronic cerebral infarctions and 10 normal subjects. We assumed that an analysis with a higher specificity would likely produce a lower mean absolute Z-score for normal brain tissue, and a more sensitive voxel-based statistical analysis would likely produce a higher absolute Z-score for in old infarct lesions, where the CBF was severely decreased. Results The inter-subject variation in the voxel values in the normal database was lower using CT-based AC, compared with Chang’s AC, for most of the brain regions. The absolute Z-score indicating a SPECT count reduction in infarct lesions was also significantly higher in the images reconstructed using CT-based AC, compared with Chang’s AC (P = 0.003). The mean absolute value of the Z-score in the 10 intact brains was significantly lower in the images reconstructed using CT-based AC than in those reconstructed using Chang’s AC (P = 0.005). Conclusions Non-uniform CT-based AC by integrated SPECT/CT significantly improved sensitivity and the specificity of the voxel-based statistical analyses for regional SPECT count reductions, compared with

  3. Comparison of diffusion tensor, dynamic susceptibility contrast MRI and (99m)Tc-Tetrofosmin brain SPECT for the detection of recurrent high-grade glioma.

    PubMed

    Alexiou, George A; Zikou, Anastasia; Tsiouris, Spyridon; Goussia, Anna; Kosta, Paraskevi; Papadopoulos, Athanasios; Voulgaris, Spyridon; Tsekeris, Pericles; Kyritsis, Athanasios P; Fotopoulos, Andreas D; Argyropoulou, Maria I

    2014-09-01

    Treatment induced necrosis is a relatively frequent finding in patients treated for high-grade glioma. Differentiation by imaging modalities between glioma recurrence and treatment induced necrosis is not always straightforward. This is a comparative study of diffusion tensor imaging (DTI), dynamic susceptibility contrast MRI and (99m)Tc-Tetrofosmin brain single-photon emission computed tomography (SPECT) for differentiation of recurrent glioma from treatment induced necrosis. A prospective study was made of 30 patients treated for high-grade glioma who had suspected recurrent tumor on follow-up MRI. All had been treated by surgical resection of the tumor followed by standard postoperative radiotherapy with chemotherapy. No residual tumor had been found on brain imaging immediately after the initial treatment. All the patients were studied with dynamic susceptibility contrast brain MRI and, within a week, (99m)Tc-Tetrofosmin brain SPECT. Both (99m)Tc-Tetrofosmin brain SPECT and dynamic susceptibility contrast MRI could discriminate between tumor recurrence and treatment induced necrosis with 100% sensitivity and 100% specificity. An apparent diffusion coefficient (ADC) ratio cut-off value of 1.27 could differentiate recurrence from treatment induced necrosis with 65% sensitivity and 100% specificity and a fractional anisotropy (FA) ratio cut-off value of 0.47 could differentiate recurrence from treatment induced necrosis with 57% sensitivity and 100% specificity. A significant correlation was demonstrated between (99m)Tc-Tetrofosmin uptake ratio and rCBV (P=0.003). Dynamic susceptibility contrast MRI and brain SPECT with (99m)Tc-Tetrofosmin had the same accuracy and may be used to detect recurrent tumor following treatment for glioma. DTI also showed promise for the detection of recurrent tumor, but was inferior to both dynamic susceptibility contrast MRI and brain SPECT. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Analysis of SPECT brain images for the diagnosis of Alzheimer's disease using moments and support vector machines.

    PubMed

    Salas-Gonzalez, Diego; Górriz, Juan M; Ramírez, Javier; López, Miriam; Illan, Ignacio A; Segovia, Fermín; Puntonet, Carlos G; Gómez-Río, Manuel

    2009-09-11

    This paper presents a computer-aided diagnosis technique for improving the accuracy of diagnosing the Alzheimer's type dementia. The proposed methodology is based on the calculation of the skewness for each m-by-m-by-m sliding block of the SPECT brain images. The center pixel in this m-by-m-by-m block is replaced by the skewness value to build a new 3-D brain image which is used for classification purposes. After that, voxels which present a Welch's t-statistic between classes, Normal and Alzheimer's images, higher (or lower) than a threshold are selected. The mean, standard deviation, skewness and kurtosis are calculated for these selected voxels and they are subjected as features to linear kernel based support vector machine classifier. The proposed methodology reaches accuracy higher than 99% in the classification task.

  5. Thallium-201 SPECT in the evaluation of early effects on brain tumors treated with stereotactic irradiation.

    PubMed

    Tomura, Noriaki; Izumi, Jun-ichi; Anbai, Akira; Takahashi, Satoshi; Sakuma, Ikuo; Omachi, Koichi; Kidani, Hiroyuki; Sasaki, Kazuhumi; Watarai, Jiro; Suzuki, Akira; Mizoi, Kazuo

    2005-02-01

    To determine whether thallium-201 SPECT can predict response to stereotactic irradiation (STI) earlier than magnetic resonance imaging (MRI), the change in tumor size measured by MRI was compared with the change in tumor activity measured by Tl-201 SPECT before and after STI. Twenty-one tumors in 16 patients with intracranial tumors were treated by STI. Tl-201 SPECT was performed within 1 week before the beginning of STI and within 1 week after the end of STI in all patients. All patients underwent MRI within 1 week before the beginning of STI, and 14 patients (19 tumors) underwent MRI within 1 week after the end of STI. Follow-up MRI was performed 1 to 2 months after the end of STI in 14 patients (16 tumors). The activity of Tl-201 in the tumor divided by that of the uninvolved symmetric area was defined as the Tl-index. The change in tumor size immediately and 1 to 2 months after STI was compared with the change in Tl-index immediately after STI. No significant relationship between the ratio of tumor size immediately after STI and the ratio of Tl-index immediately after STI was found. A significant correlation (r = 0.69, P <0.05) between the ratio of tumor size 1 to 2 months after STI and the ratio of Tl-index immediately after STI was found. This study suggests that Tl-201 SPECT immediately after STI can predict treatment response 1 to 2 months after STI, and that Tl-201 SPECT can be an early indicator of treatment response.

  6. Clinical application of 3D arterial spin-labeled brain perfusion imaging for Alzheimer disease: comparison with brain perfusion SPECT.

    PubMed

    Takahashi, H; Ishii, K; Hosokawa, C; Hyodo, T; Kashiwagi, N; Matsuki, M; Ashikaga, R; Murakami, T

    2014-05-01

    Alzheimer disease is the most common neurodegenerative disorder with dementia, and a practical and economic biomarker for diagnosis of Alzheimer disease is needed. Three-dimensional arterial spin-labeling, with its high signal-to-noise ratio, enables measurement of cerebral blood flow precisely without any extrinsic tracers. We evaluated the performance of 3D arterial spin-labeling compared with SPECT, and demonstrated the 3D arterial spin-labeled imaging characteristics in the diagnosis of Alzheimer disease. This study included 68 patients with clinically suspected Alzheimer disease who underwent both 3D arterial spin-labeling and SPECT imaging. Two readers independently assessed both images. Kendall W coefficients of concordance (K) were computed, and receiver operating characteristic analyses were performed for each reader. The differences between the images in regional perfusion distribution were evaluated by means of statistical parametric mapping, and the incidence of hypoperfusion of the cerebral watershed area, referred to as "borderzone sign" in the 3D arterial spin-labeled images, was determined. Readers showed K = 0.82/0.73 for SPECT/3D arterial spin-labeled imaging, and the respective areas under the receiver operating characteristic curve were 0.82/0.69 for reader 1 and 0.80/0.69 for reader 2. Statistical parametric mapping showed that the perisylvian and medial parieto-occipital perfusion in the arterial spin-labeled images was significantly higher than that in the SPECT images. Borderzone sign was observed on 3D arterial spin-labeling in 70% of patients misdiagnosed with Alzheimer disease. The diagnostic performance of 3D arterial spin-labeling and SPECT for Alzheimer disease was almost equivalent. Three-dimensional arterial spin-labeled imaging was more influenced by hemodynamic factors than was SPECT imaging. © 2014 by American Journal of Neuroradiology.

  7. Differences at brain SPECT between depressed females with and without adult ADHD and healthy controls: etiological considerations

    PubMed Central

    Gardner, Ann; Salmaso, Dario; Varrone, Andrea; Sanchez-Crespo, Alejandro; Bejerot, Susanne; Jacobsson, Hans; Larsson, Stig A; Pagani, Marco

    2009-01-01

    Background Comorbidity between Attention Deficit Hyperactivity Disorder (ADHD) and mood disorders is common. Alterations of the cerebellum and frontal regions have been reported in neuro-imaging studies of ADHD and major depression. Methods Thirty chronically depressed adult females of whom 16 had scores below, and 14 scores above, cut-offs on the 25-items Wender Utah Retrospective Scale (WURS-25) and the Wender-Reimherr Adult Attention Deficit Disorder Scale (WRAADDS) were divided into subgroups designated "Depression" and "Depression + ADHD", respectively. Twenty-one of the patients had some audiological symptom, tinnitus and/or hearing impairment. The patients were investigated with other rating scales and 99mTc-HMPAO SPECT. Controls for 99mTc-HMPAO SPECT were 16 healthy females. SPECT was analyzed by both statistical parametric mapping (SPM2) and the computerized brain atlas (CBA). Discriminant analysis was performed on the volumes of interest generated by the CBA, and on the scores from rating scales with the highest group differences. Results The mean score of a depression rating scale (MADRS-S) was significantly lower in the "Depression" subgroup compared to in the "Depression + ADHD" subgroup. There was significantly decreased tracer uptake within the bilateral cerebellum at both SPM and CBA in the "Depression + ADHD" subgroup compared to in the controls. No decrease of cerebellar tracer uptake was observed in "Depression". Significantly increased tracer uptake was found at SPM within some bilateral frontal regions (Brodmann areas 8, 9, 10, 32) in the "Depression + ADHD" subgroup compared to in "Depression". An accuracy of 100% was obtained for the discrimination between the patient groups when thalamic uptake was used in the analysis along with scores from Socialization and Impulsivity scales. Conclusion The findings confirm the previous observation of a cerebellar involvement in ADHD. Higher bilateral frontal 99mTc-HMPAO uptake in "Depression + ADHD

  8. Differential diagnosis of posterior fossa brain tumors: Multiple discriminant analysis of Tl-SPECT and FDG-PET.

    PubMed

    Yamauchi, Moritaka; Okada, Tomohisa; Okada, Tsutomu; Yamamoto, Akira; Fushimi, Yasutaka; Arakawa, Yoshiki; Miyamoto, Susumu; Togashi, Kaori

    2017-08-01

    This study investigated the combined capability of thallium-201 (Tl)-SPECT and fluorine-18-fluoro-deoxy-glucose (FDG)-PET for differential diagnosis of posterior fossa brain tumors using multiple discriminant analysis.This retrospective study was conducted under approval of the institutional review board. In the hospital information system, 27 patients with posterior fossa intra-axial tumor between January 2009 and June 2015 were enrolled and grouped as the following 7 entities: low grade glioma (LGG) 6, anaplastic astrocytoma (AA) 2, glioblastoma (GBM) 3, medulloblastoma (MB) 3, hemangioblastoma (HB) 6, metastatic tumor (Mets) 3, and malignant lymphoma (ML) 4. Tl and FDG uptakes were measured at the tumors and control areas, and several indexes were derived. Using indexes selected by the stepwise method, discriminant analysis was conducted with leave-one-out cross-validation.The predicted accuracy for tumor classification was 70.4% at initial analysis and 55.6% at cross-validation to differentiate 7 tumor entities. HB, LGG, and ML were well-discriminated, but AA was located next to LGG. GBM, MB, and Mets largely overlapped and could not be well distinguished even applying multiple discriminant analysis. Correct classification in the original and cross-validation analyses was 44.4% and 33.3% for Tl-SPECT and 55.6% and 48.1% for FDG-PET.

  9. Functional imaging of brain maturation in humans using iodine-123 iodoamphetamine and SPECT

    SciTech Connect

    Rubinstein, M.; Denays, R.; Ham, H.R.; Piepsz, A.; VanPachterbeke, T.; Haumont, D.; Nol, P. )

    1989-12-01

    The application of regional cerebral blood flow (rCBF) study by means of lipophilic radiotracers and single photon emission computed (SPECT) devices in very young infants is hampered by the considerable changes of rCBF pattern as a result of the cerebral maturation process. In an attempt to determine the normal evolution of ({sup 123}I)IMP SPECT pattern as a function of age, we retrospectively selected the studies of 30 babies with normal clinical examination, EEG and CT or ultrasound scans at time of SPECT. There was a marked predominance of the thalamic perfusion over cortical areas until the end of the second month. The distribution of regional cortical activity followed a strict sequence. The perfusion of both parietal and occipital areas was well-visualized around the 40th week of gestational age and thereafter rapidly rose, always, however, with a slight predominance of the parietal activity. At the opposite, frontal activity which remained scarcely recognizable up to the second month tremendously rose to present the adult-like pattern at the beginning of the second year. The rCBF changes described above are well in agreement with the behavioral evolution occurring during prime infancy.

  10. Development and validation of the random walk algorithm: application to the classification of diffuse heterogeneity in brain SPECT perfusion images.

    PubMed

    Modzelewski, Romain; de la Rue, Thierry; Janvresse, Elise; Hitzel, Anne; Menard, Jean François; Manrique, Alain; Gardin, Isabelle; Gerardin, Emmanuel; Hannequin, Didier; Vera, Pierre

    2008-01-01

    Heterogeneity analysis has been studied for radiological imaging, but few methods have been developed for functional images. Diffuse heterogeneous perfusion frequently appears in brain single photon emission computed tomography (SPECT) images, but objective quantification is lacking. An automatic method, based on random walk (RW) theory, has been developed to quantify perfusion heterogeneity. We assess the robustness of our algorithm in differentiating levels of diffuse heterogeneity even when focal defects are present. Heterogeneity is quantified by counting R (percentage), the mean rate of visited pixels in a fixed number of steps of the stochastic RW process. The algorithm has been tested on the numerical anthropomorphic Zubal head phantom. Seven diffuse cortical heterogeneity levels were simulated with an adjustable Gaussian function and 6 temporoparietal focal defects simulating Alzheimer Disease, leading to 42 phantoms. Data were projected and smoothed (full width at half maximum, 5.5 mm), and Poisson noise was added to the 64 projections. The SPECT data were reconstructed using filtered backprojection (Hamming filter, 0.5 c/p). R values for different levels of perfusion defect and diffuse heterogeneity were evaluated on 3 parameters: the number of slices studied (20 vs 40), the use of Talairach normalization versus original space, and the use of a cortical mask within the Talairach space. For each parameter, regression lines for heterogeneity and temporoparietal defect quantification were analyzed by covariance statistics. R values were also evaluated on SPECT images performed on 25 subjects with suspected focal dementia and on 15 normal controls. Scans were blindly ranked by 2 experienced nuclear physicians according to the degree of diffuse heterogeneity. Variability of R was smaller than 0.17% for repeated measurements. R was more particularly influenced by diffuse heterogeneity compared with focal perfusion defect. The Talairach normalization had a

  11. SPECT brain imaging of the dopaminergic system in Parkinsonism using {sup 123}I and {sup 99m}Tc labeled agents

    SciTech Connect

    Du Yong

    2004-12-01

    SPECT brain imaging of the dopaminergic system using {sup 123}I and {sup 99m}Tc labeled agents, especially the simultaneous imaging of both pre- and postsynaptic neurons, promises to provide accurate diagnosis and differentiation of Parkinsonism. However, there are many degrading factors that affect the quality and quantitative accuracy of the SPECT images. These degrading factors limit the potential clinical applications of brain SPECT imaging. In this work, we studied these degrading factors by developing and validating a Monte Carlo (MC) method that provides accurate SPECT simulation with detailed modeling of the photon interactions inside the collimator detector system. To compensate for the partial volume effect (PVE) in the SPECT images caused by finite spatial resolution, we developed a new PVE compensation method that takes into account the effects of nonlinearity in iterative reconstruction-based compensation for image degrading factors, including attenuation, scatter, and collimator detector response. Compensation using the new method greatly improved the quantitative accuracy of brain SPECT images. We have also developed model-based method that can accurately estimate the downscatter and crosstalk contamination in the {sup 123}I imaging and the simultaneous {sup 123}I/{sup 99m}Tc dual-isotope imaging. Based on the model-based method, two different approaches to model-based downscatter and crosstalk contamination compensation were proposed. Both methods are based on iterative reconstruction and include compensation for other imaging degrading factors. The model-based downscatter and crosstalk compensation method provided greatly improved accuracy of activity estimates with little effect on the precision. Finally, optimization of energy windows for simultaneous {sup 123}I/{sup 99m}Tc acquisition was performed to find the energy windows with the best trade-off between minimizing the crosstalk and maximizing the detection efficiency for simultaneous

  12. Structural and Perfusion Abnormalities of Brain on MRI and Technetium-99m-ECD SPECT in Children With Cerebral Palsy: A Comparative Study.

    PubMed

    Rana, Kamer Singh; Narwal, Varun; Chauhan, Lokesh; Singh, Giriraj; Sharma, Monica; Chauhan, Suneel

    2016-04-01

    Cerebral palsy has traditionally been associated with hypoxic ischemic brain damage. This study was undertaken to demonstrate structural and perfusion brain abnormalities. Fifty-six children diagnosed clinically as having cerebral palsy were studied between 1 to 14 years of age and were subjected to 3 Tesla magnetic resonance imaging (MRI). Brain and Technetium-99m-ECD brain single-photon emission computed tomography (SPECT) scan. Male to female ratio was 1.8:1 with a mean age of 4.16 ± 2.274 years. Spastic cerebral palsy was the most common type, observed in 91%. Birth asphyxia was the most common etiology (69.6%). White matter changes (73.2%) such as periventricular leukomalacia and corpus callosal thinning were the most common findings on MRI. On SPECT all cases except one revealed perfusion impairments in different regions of brain. MRI is more sensitive in detecting white matter changes, whereas SPECT is better in detecting cortical and subcortical gray matter abnormalities of perfusion. © The Author(s) 2015.

  13. NeuroGam Software Analysis in Epilepsy Diagnosis Using 99mTc-ECD Brain Perfusion SPECT Imaging.

    PubMed

    Fu, Peng; Zhang, Fang; Gao, Jianqing; Jing, Jianmin; Pan, Liping; Li, Dongxue; Wei, Lingge

    2015-09-20

    BACKGROUND The aim of this study was to explore the value of NeuroGam software in diagnosis of epilepsy by 99Tcm-ethyl cysteinate dimer (ECD) brain imaging. MATERIAL AND METHODS NeuroGam was used to analyze 52 cases of clinically proven epilepsy by 99Tcm-ECD brain imaging. The results were compared with EEG and MRI, and the positive rates and localization to epileptic foci were analyzed. RESULTS NeuroGam analysis showed that 42 of 52 epilepsy cases were abnormal. 99Tcm-ECD brain imaging revealed a positive rate of 80.8% (42/52), with 36 out of 42 patients (85.7%) clearly showing an abnormal area. Both were higher than that of brain perfusion SPECT, with a consistency of 64.5% (34/52) using these 2 methods. Decreased regional cerebral blood flow (rCBF) was observed in frontal (18), temporal (20), and parietal lobes (2). Decreased rCBF was seen in frontal and temporal lobes in 4 out of 36 patients, and in temporal and parietal lobes of 2 out of 36 patients. NeuroGam further showed that the abnormal area was located in a different functional area of the brain. EEG abnormalities were detected in 29 out of 52 patients (55.8%) with 16 cases (55.2%) clearly showing an abnormal area. MRI abnormalities were detected in 17 out of 43 cases (39.5%), including 9 cases (52.9%) clearly showing an abnormal area. The consistency of NeuroGam software analysis, and EEG and MRI were 48.1% (25/52) and 34.9% (15/43), respectively. CONCLUSIONS NeuroGam software analysis offers a higher sensitivity in detecting epilepsy than EEG or MRI. It is a powerful tool in 99Tcm-ECD brain imaging.

  14. Alzheimer disease: Quantitative analysis of I-123-iodoamphetamine SPECT brain imaging

    SciTech Connect

    Hellman, R.S.; Tikofsky, R.S.; Collier, B.D.; Hoffmann, R.G.; Palmer, D.W.; Glatt, S.L.; Antuono, P.G.; Isitman, A.T.; Papke, R.A.

    1989-07-01

    To enable a more quantitative diagnosis of senile dementia of the Alzheimer type (SDAT), the authors developed and tested a semiautomated method to define regions of interest (ROIs) to be used in quantitating results from single photon emission computed tomography (SPECT) of regional cerebral blood flow performed with N-isopropyl iodine-123-iodoamphetamine. SPECT/IMP imaging was performed in ten patients with probable SDAT and seven healthy subjects. Multiple ROIs were manually and semiautomatically generated, and uptake was quantitated for each ROI. Mean cortical activity was estimated as the average of the mean activity in 24 semiautomatically generated ROIs; mean cerebellar activity was determined from the mean activity in separate ROIs. A ratio of parietal to cerebellar activity less than 0.60 and a ratio of parietal to mean cortical activity less than 0.90 allowed correct categorization of nine of ten and eight of ten patients, respectively, with SDAT and all control subjects. The degree of diminished mental status observed in patients with SDAT correlated with both global and regional changes in IMP uptake.

  15. The impacts of acute carbon monoxide poisoning on the brain: Longitudinal clinical and 99mTc ethyl cysteinate brain SPECT characterization of patients with persistent and delayed neurological sequelae.

    PubMed

    Tsai, Chung-Fen; Yip, Ping-Keung; Chen, Shao-Yuan; Lin, Jen-Cheng; Yeh, Zai-Ting; Kung, Lan-Yu; Wang, Cheng-Yi; Fan, Yu-Ming

    2014-04-01

    Acute carbon monoxide (CO) poisoning poses a significant threat to the central nervous system. It can cause brain injury and diverse neurological deficits including persistent neurological sequelae (PNS) and delayed neurological sequelae (DNS). The study aimed to investigate the long-term impacts of acute CO poisoning on brain perfusion and neurological function, and to explore potential differences between PNS and DNS patients. We evaluated brain perfusion using (99m)Tc ethyl cysteinate (ECD) brain single photon emission computed tomography (SPECT) and assessed clinical neurological symptoms and signs one month following acute poisoning. For DNS patients, ECD SPECT and clinical evaluation were performed when their delayed symptoms appeared. All patients had follow-up SPECT imaging, along with clinical assessments six months following poisoning. 12 PNS and 12 DNS patients were recruited between 2007 and 2010. Clinically, the main characteristic presentations were cognitive decline, emotional instability, and gait disturbance. SPECT imaging demonstrated consistent frontal hypoperfusion of varying severities in all patients, which decreased in severity at follow-up imaging. DNS patients usually had more severe symptoms and perfusion defects, along with worse clinical outcomes than the PNS group. These results suggest that acute CO poisoning might lead to long term brain injuries and neurological sequelae, particularly in DNS patients. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Role of Brain Perfusion SPECT with 99mTc HMPAO in the Assessment of Response to Drug Therapy in Patients with Autoimmune Vasculitis: A Prospective Study

    PubMed Central

    Mauro, Liberatore; Manuela, Morreale; Valentina, Megna; Sara, Collorone; Chondrogiannis, Sotirios; Maria, Drudi Francesco; Christos, Anagnostou; Liana, Civitelli; Ada, Francia; Maffione, Anna Margherita; Marzola, Maria Cristina; Rubello, Domenico

    2015-01-01

    Background: The diagnosis of vasculitis in the brain remains a quite difficult achievement. To the best of our knowledge, there is no imaging method reported in literature which is capable of reaching to a diagnosis of vasculitis with very high sensitivity. Aim: The aim of this study was to determine whether perfusion brain single photon emission computed tomography (SPECT) can be usefully employed in monitoring the treatment of vasculitis, allowing treating only potentially responder patients and avoiding the side effects on patients who do not respond. Materials and Methods: Twenty patients (two males and 18 females) suffering from systemic lupus erythematosus (SLE; n = 5), Behcet's disease (BD; n = 5), undifferentiated vasculitis (UV; n = 5), and Sjogren's syndrome (SS; n = 5) were included in the study. All patients underwent a wide neurological anamnestic investigation, a complete objective neurological examination and SPECT of the brain with 99mTc-hexamethyl-propylene-aminoxime (HMPAO). The brain SPECT was then repeated after appropriate medical treatment. The neurological and neuropsychiatric follow-up was performed at 6 months after the start of the treatment. Results: Overall, the differences between the scintigraphic results obtained after and before the medical treatment indicated a statistically significant increase of the cerebral perfusion (CP). In 19 out of 200 regions of interest (ROI) studied, the difference between pre- and post treatment percentages had negative sign, indicating a worsening of CP. This latter event has occurred six times (five in the same patients) in the UV, 10 times (eight in the same patients) in the SLE, never in BD, and three times (two in the same patient) in the SS. Conclusion: The reported results seem to indicate the possibility of identifying, by the means of a brain SPECT, responder and nonresponder (unchanged or worsened CP) patients, affected by autoimmune vasculitis, to the therapy. PMID:25973400

  17. Semiquantitative analysis using thallium-201 SPECT for differential diagnosis between tumor recurrence and radiation necrosis after gamma knife surgery for malignant brain tumors.

    PubMed

    Matsunaga, Shigeo; Shuto, Takashi; Takase, Hajime; Ohtake, Makoto; Tomura, Nagatsuki; Tanaka, Takahiro; Sonoda, Masaki

    2013-01-01

    Semiquantitative analysis of thallium-201 chloride single photon emission computed tomography (201Tl SPECT) was evaluated for the discrimination between recurrent brain tumor and delayed radiation necrosis after gamma knife surgery (GKS) for metastatic brain tumors and high-grade gliomas. The medical records were reviewed of 75 patients, including 48 patients with metastatic brain tumor and 27 patients with high-grade glioma who underwent GKS in our institution, and had suspected tumor recurrence or radiation necrosis on follow-up neuroimaging and deteriorating clinical status after GKS. Analysis of 201Tl SPECT data used the early ratio (ER) and the delayed ratio (DR) calculated as tumor/normal average counts on the early and delayed images, and the retention index (RI) as the ratio of DR to ER. A total of 107 tumors were analyzed with 201Tl SPECT. Nineteen lesions were removed surgically and histological diagnoses established, and the other lesions were evaluated with follow-up clinical and neuroimaging examinations after GKS. The final diagnosis was considered to be recurrent tumor in 65 lesions and radiation necrosis in 42 lesions. Semiquantitative analysis demonstrated significant differences in DR (P=.002) and RI (P<.0001), but not in ER (P=.372), between the tumor recurrence and radiation necrosis groups, and no significant differences between metastatic brain tumors and high-grade gliomas in all indices (P=.926 for ER, P=.263 for DR, and P=.826 for RI). Receiver operating characteristics analysis indicated that RI was the most informative index with the optimum threshold of 0.775, which provided 82.8% sensitivity, 83.7% specificity, and 82.8% accuracy. Semiquantitative analysis of 201Tl SPECT provides useful information for the differentiation between tumor recurrence and radiation necrosis in metastatic brain tumors and high-grade gliomas after GKS, and the RI may be the most valuable index for this purpose. Copyright © 2013 Elsevier Inc. All rights

  18. Semiquantitative Analysis Using Thallium-201 SPECT for Differential Diagnosis Between Tumor Recurrence and Radiation Necrosis After Gamma Knife Surgery for Malignant Brain Tumors

    SciTech Connect

    Matsunaga, Shigeo; Shuto, Takashi; Takase, Hajime; Ohtake, Makoto; Tomura, Nagatsuki; Tanaka, Takahiro; Sonoda, Masaki

    2013-01-01

    Purpose: Semiquantitative analysis of thallium-201 chloride single photon emission computed tomography ({sup 201}Tl SPECT) was evaluated for the discrimination between recurrent brain tumor and delayed radiation necrosis after gamma knife surgery (GKS) for metastatic brain tumors and high-grade gliomas. Methods and Materials: The medical records were reviewed of 75 patients, including 48 patients with metastatic brain tumor and 27 patients with high-grade glioma who underwent GKS in our institution, and had suspected tumor recurrence or radiation necrosis on follow-up neuroimaging and deteriorating clinical status after GKS. Analysis of {sup 201}Tl SPECT data used the early ratio (ER) and the delayed ratio (DR) calculated as tumor/normal average counts on the early and delayed images, and the retention index (RI) as the ratio of DR to ER. Results: A total of 107 tumors were analyzed with {sup 201}Tl SPECT. Nineteen lesions were removed surgically and histological diagnoses established, and the other lesions were evaluated with follow-up clinical and neuroimaging examinations after GKS. The final diagnosis was considered to be recurrent tumor in 65 lesions and radiation necrosis in 42 lesions. Semiquantitative analysis demonstrated significant differences in DR (P=.002) and RI (P<.0001), but not in ER (P=.372), between the tumor recurrence and radiation necrosis groups, and no significant differences between metastatic brain tumors and high-grade gliomas in all indices (P=.926 for ER, P=.263 for DR, and P=.826 for RI). Receiver operating characteristics analysis indicated that RI was the most informative index with the optimum threshold of 0.775, which provided 82.8% sensitivity, 83.7% specificity, and 82.8% accuracy. Conclusions: Semiquantitative analysis of {sup 201}Tl SPECT provides useful information for the differentiation between tumor recurrence and radiation necrosis in metastatic brain tumors and high-grade gliomas after GKS, and the RI may be the most

  19. Computer-assisted diagnostic system for neurodegenerative dementia using brain SPECT and 3D-SSP.

    PubMed

    Ishii, Kazunari; Kanda, Tomonori; Uemura, Takafumi; Miyamoto, Naokazu; Yoshikawa, Toshiki; Shimada, Kenichi; Ohkawa, Shingo; Minoshima, Satoshi

    2009-05-01

    To develop a computer-assisted automated diagnostic system to distinguish among Alzheimer disease (AD), dementia with Lewy bodies (DLB), and other degenerative disorders in patients with mild dementia. Single photon emission computed tomography (SPECT) images with injection of N-Isopropyl-p-[(123)I]iodoamphetamine (IMP) were obtained from patients with mild degenerative dementia. First, datasets from 20 patients mild AD, 15 patients with dementia with DLB, and 17 healthy controls were used to develop an automated diagnosing system based on three-dimensional stereotactic surface projections (3D-SSP). AD- and DLB-specific regional templates were created using 3D-SSP, and critical Z scores in the templates were established. Datasets from 50 AD patients, 8 DLB patients, and 10 patients with non-AD/DLB type degenerative dementia (5 with frontotemporal dementia and 5 with progressive supranuclear palsy) were then used to test the diagnostic accuracy of the optimized automated system in comparison to the diagnostic interpretation of conventional IMP-SPECT images. These comparisons were performed to differentiate AD and DLB from non-AD/DLB and to distinguish AD from DLB. A receiver operating characteristic (ROC) analysis was performed. The area under the ROC curve (Az) and the accuracy of the automated diagnosis system were 0.89 and 82%, respectively, for AD/DLB vs. non-AD/DLB patients, and 0.70 and 65%, respectively, for AD vs. DLB patients. The mean Az and the accuracy of the visual inspection were 0.84 and 77%, respectively, for AD/DLB vs. non-AD/DLB patients, and 0.70 and 65%, respectively, for AD vs. DLB patients. The mean Az and the accuracy of the combination of visual inspection and this system were 0.96 and 91%, respectively, for AD/DLB vs. non-AD/DLB patients, and 0.70 and 66%, respectively, for AD vs. DLB patients. The system developed in the present study achieved as good discrimination of AD, DLB, and other degenerative disorders in patients with mild dementia

  20. An easy Z-score imaging system for discrimination between very early Alzheimer's disease and controls using brain perfusion SPECT in a multicentre study.

    PubMed

    Matsuda, Hiroshi; Mizumura, Sunao; Nagao, Takehiko; Ota, Tsuneyoshi; Iizuka, Tomomichi; Nemoto, Kiyotaka; Kimura, Michihiro; Tateno, Amane; Ishiwata, Akiko; Kuji, Ichiei; Arai, Heii; Homma, Akira

    2007-03-01

    In Alzheimer's disease (AD), regional cerebral blood flow (rCBF) in the posterior cingulate gyrus and precuneus has been reported to decrease even at a very early stage. We performed a multicentre SPECT study to evaluate the discrimination ability of an easy Z-score imaging system (eZIS) by detecting an rCBF decrease in this area with a common normal database between very early AD patients at the stage of mild cognitive impairment and age-matched healthy volunteers. Brain perfusion SPECT images of 40 Alzheimer's disease patients and 40 healthy volunteers were acquired from four gamma camera systems in different institutions. Systematic differences of SPECT images between different gamma cameras were corrected using conversion maps calculated from the SPECT images of the same brain phantom. Ten observers with various degrees of expertise graded eZIS results for receiver operating characteristic (ROC) curves. ROC curves for a positive Z-score in the volume of interest (VOI) of the posterior cingulate gyrus and precuneus were also analysed. An area under the ROC curve value (AZ) for ten observers showed the highest value of 0.866 on average with the smallest standard deviation of 0.027 in the condition of the lower threshold of a Z-score map of 2 without superimposition of VOI. Automated analysis of a Z-score in the VOI showed an AZ value of 0.895. Since the degree of expertise of the observers with respect to reading eZIS did not influence the performance and an eZIS can use a common normal database by converting site-specific SPECT data to the core data, the eZIS was considered to be very useful for diagnosing early AD in routine studies in many institutions.

  1. Effects of dextromethorphan on MDMA-induced serotonergic aberration in the brains of non-human primates using [123I]-ADAM/SPECT

    PubMed Central

    Ma, Kuo-Hsing; Liu, Tsung-Ta; Weng, Shao-Ju; Chen, Chien-Fu F.; Huang, Yuahn-Sieh; Chueh, Sheau-Huei; Liao, Mei-Hsiu; Chang, Kang-Wei; Sung, Chi-Chang; Hsu, Te-Hung; Huang, Wen-Sheng; Cheng, Cheng-Yi

    2016-01-01

    3,4-Methylenedioxymethamphetamine (MDMA), a common recreational drug, is known to cause serotonergic neurotoxicity in the brain. Dextromethorphan (DM) is a widely used antitussive reported to exert anti-inflammatory effect in vivo. In this study, we examined the long-term effect of MDMA on the primate serotonergic system and the protective property of DM against MDMA-induced serotonergic abnormality using single photon emission computed tomography (SPECT). Nine monkeys (Macaca cyclopis) were divided into three groups, namely control, MDMA and co-treatment (MDMA/DM). [123I]-ADAM was used as the radioligand for serotonin transporters (SERT) in SPECT scans. SERT levels of the brain were evaluated and presented as the uptake ratios (URs) of [123I]-ADAM in several regions of interest of the brain including midbrain, thalamus and striatum. We found that the URs of [123I]-ADAM were significantly lower in the brains of MDMA than control group, indicating lower brain SERT levels in the MDMA-treated monkeys. This MDMA-induced decrease in brain SERT levels could persist for over four years. However, the loss of brain SERT levels was not observed in co-treatment group. These results suggest that DM may exert a protective effect against MDMA-induced serotonergic toxicity in the brains of the non-human primate. PMID:27941910

  2. Initial experience with SPECT imaging of the brain using I-123 p-iodoamphetamine in focal epilepsy

    SciTech Connect

    LaManna, M.M.; Sussman, N.M.; Harner, R.N.; Kaplan, L.R.; Hershey, B.L.; Bernstein, D.R.; Goldstein, P.; Parker, J.A.; Wolodzko, J.G.; Popky, G.L.

    1989-06-01

    Nineteen patients with complex partial seizures refractory to medical treatment were examined with routine electroencephalography (EEG), video EEG monitoring, computed tomography or magnetic resonance imaging, neuropsychological tests and interictal single photon emission computed tomography (SPECT) with I-123 iodoamphetamine (INT). In 18 patients, SPECT identified areas of focal reduction in tracer uptake that correlated with the epileptogenic focus identified on the EEG. In addition, SPECT disclosed other areas of neurologic dysfunction as elicited on neuropsychological tests. Thus, IMP SPECT is a useful tool for localizing epileptogenic foci and their associated dynamic deficits.

  3. The time course of vasogenic oedema after focal human head injury--evidence from SPECT mapping of blood brain barrier defects.

    PubMed

    Bullock, R; Statham, P; Patterson, J; Wyper, D; Hadley, D; Teasdale, E

    1990-01-01

    We have tomographically mapped changes in the blood brain barrier (BBB) (99 mTc Pertechnetate) in 20 patients with acute contusions, and four with acute subdural haematomas in situ. The changes were related to regional CBF, (99 mTc HMPAO SPECT) T2 weighted MRI scans, CT abnormalities and the clinical features. Seventy-five percent of contusions were accompanied by a BBB abnormality, usually a "halo" around the lesion, which was more common in scans made after the second day. All contusions demonstrated "oedema" as a zone of "T2" signal on MRI or a zone of lucency on CT, and all were accompanied by a focal zone of low CBF on SPECT. Early contusional oedema appears to be cytotoxic but in certain cases, delayed blood brain barrier lesions develop, suggesting a vasogenic component.

  4. Pentavalent technetium-99m-dimercaptosuccinic acid [Tc-99m (V) DMSA] brain SPECT: does it have a place in predicting survival in patients with glioblastoma multiforme?

    PubMed

    Amin, Amr; Mustafa, M; Abd El-Hadi, E; Monier, A; Badwey, A; Saad, E

    2015-01-01

    Pentavalent technetium-99m dimercaptosuccinic acid (Tc-99m (V) DMSA) is reported as a useful tool for detection of residual or recurrent gliomas. We aimed to investigate the prognostic value of Tc-99m (V) DMSA brain SPECT in patients with glioblastoma multiforme (GBM). 40 patients [21 males and 19 females; mean age 48.6 ± 12.2 years] with GBM were included. Tc-99m (V) DMSA brain SPECT was done after surgery and before onset of radiation therapy or chemotherapy (Baseline study), at 4-6 weeks and at 6 months as a follow-up after therapy. The end point of the study was clinical follow-up for 2 years and/or death. 4-6 weeks after therapy, 40 and 60 % had negative and positive Tc-99m (V) DMSA for viable tumor tissues respectively (P = 0.09). At 6 months follow-up, 62.5 % of (V) DMSA negative patients and 12.5 % of the positive subjects were responders (P = 0.001). The median over-all survival (OS) of all patients was 12.3 month [range 5-24 month]. Patients with positive (V) DMSA had worse survival (8.87 month) compared to the negative ones (16.67 month) (P = 0.0001). Multivariate Cox regression analysis showed that Tc-99m (V) DMSA brain SPECT studies at 4-6 weeks and 6-months follow-up were independent prognostic factors for survival [OR 1.069; 95 % CI 1.417-2.174; P = 0.03 and OR 1.055; 95 % CI 0.821-1.186; P = 0.01 respectively]. Stratification of tumors into risk groups based on prognostic parameters may improve outcome by altering or intensifying treatment methods. Technetium-99m dimercaptosuccinic acid brain SPECT may have an additional prognostic role in patients with GBM which needs further evaluation in larger future series.

  5. Brain and platelet serotonin transporter in humans-correlation between [123I]-ADAM SPECT and serotonergic measurements in platelets.

    PubMed

    Uebelhack, Ralf; Franke, Leonora; Herold, Nathalie; Plotkin, Michael; Amthauer, Holger; Felix, Roland

    2006-10-09

    Blood platelets are thought to be a useful peripheral model for investigating the central serotoninergic mechanisms associated with the serotonin transporter (SERT). On the other hand, an in vivo investigation of SERT in the human brain has been made possible by the development of several promising SPECT radioligands, such as [123I]-ADAM. The aim of the present study was to investigate the possible correlation between the SERT measurements in the brain and those in platelets. Forty-four subjects (14 healthy subjects and 30 patients with the diagnosis of major depression or schizoaffective disorder) were examined. The [123I]-ADAM binding was assessed 4h after injection using MR-guided regions of interest (ROIs) in the midbrain and cerebellum. In a parallel investigation, serotonin (5HT) concentration and kinetic characteristics of 5HT uptake activity (Vmax and Km) were determined in platelet-rich plasma. Overall, there was no significant correlation between the V(max) of 5HT uptake in platelets and the specific to nonspecific partition coefficient of [123I]-ADAM (V''3) in the midbrain. However, low but significant Pearson correlation coefficients were found for V(max) and normalised activities measured in the midbrain (r=0.310, p=0.043). The correlation was stronger and significant in females (n=20, r=0.629, p=0.003) but low and non-significant in the 24 males (r=0.104). Although confirmation is necessary, it seems that the relationship between different indices of [123I]-ADAM binding in the brain and 5HT uptake characteristics in platelets is complex, nonuniform, and possibly gender-specific.

  6. Early brain perfusion improvement after ventriculoperitoneal shunt surgery in patients with idiopathic normal pressure hydrocephalus evaluated by 99mTc-HMPAO SPECT - preliminary report.

    PubMed

    Nocuń, Anna; Mosiewicz, Anna; Kaczmarczyk, Robert; Kazalska, Teresa; Czekajska-Chehab, Elżbieta; Chrapko, Beata; Trojanowski, Tomasz

    2015-01-01

    Idiopathic normal pressure hydrocephalus (iNPH) is a clinical syndrome that consists of the triad: gait disturbance, mental deterioration and urinary incontinence associated with normal cerebrospinal fluid pressure (CSF), without pre-existing abnormalities. The most popular treatment option is surgical implantation of a shunt. Brain perfusion increase occurring months or years after successful shunt surgery is well described in the literature. Early improvement of perfusion is not well documented. Therefore, the objective of the present study was to determine patterns of brain perfusion changes 3-6 days after the ventriculoperitoneal shunting in patients with iNPH by using 99mTc-HMPAO SPECT. Sixteen patients with iNPH (9 women, 7 men, mean age 64.1 ± 12.7 years) who underwent ventriculoperitoneal shunt surgery were included into the study group. Indications for implanting a shunt were based on clinical history, neuroimaging and CSF dynamic studies with an infusion test. Brain perfusion SPECT was performed 1-2 days before and 3-6 days after the surgical treatment. For comparison of perfusion before and after the surgery SPECT scans were assessed visually and semiquantitatively with voxel based analysis. No side effects were observed after the surgery. Brain perfusion improvement after shunting was observed in 10 patients (62.5%). Patterns of perfusion changes varied between patients, with combinations of different bilateral and lateralized brain regions involved. Perfusion increased in the whole brain (3 patients), in the right cerebral hemisphere (1 patient) or in the separate cerebral regions (6 patients): frontal, parietal, temporal, cerebellum, cingulate gyrus. Perfusion improvement was predominantly observed in the frontal lobes: right frontal (3 cases, 18.8%), left frontal (3 cases, 18.8%). Cerebral perfusion is recovered promptly after ventriculoperitoneal shunt surgery in about 60% of patients with iNPH. This improvement may be global or regional in

  7. Equivalent brain SPECT perfusion changes underlying therapeutic efficiency in pharmacoresistant depression using either high-frequency left or low-frequency right prefrontal rTMS.

    PubMed

    Richieri, Raphaëlle; Boyer, Laurent; Padovani, Romain; Adida, Marc; Colavolpe, Cécile; Mundler, Olivier; Lançon, Christophe; Guedj, Eric

    2012-12-03

    Functional neuroimaging studies have suggested similar mechanisms underlying antidepressant effects of distinct therapeutics. This study aimed to determine and compare functional brain patterns underlying the antidepressant response of 2 distinct protocols of repetitive transcranial magnetic stimulation (rTMS). 99mTc-ECD SPECT was performed before and after rTMS of dorsolateral prefrontal cortex in 61 drug-resistant right-handed patients with major depression, using high frequency (10Hz) left-side stimulation in 33 patients, and low frequency (1Hz) right-side stimulation in 28 patients. Efficiency of rTMS response was defined as at least 50% reduction of the baseline Beck Depression Inventory score. We compared the whole-brain voxel-based brain SPECT changes in perfusion after rTMS, between responders and non-responders in the whole sample (p<0.005, uncorrected), and separately in the subgroup of patients with left- and right-stimulation. Before rTMS, the left- and right-prefrontal stimulation groups did not differ from clinical data and brain SPECT perfusion. rTMS efficiency (evaluated on % of responders) was statistically equivalent in the two groups of patients. In the whole-group of responder patients, a perfusion decrease was found after rTMS, in comparison to non-responders, within the left perirhinal cortex (BA35, BA36). This result was secondarily confirmed separately in the two subgroups, i.e. after either left stimulation (p=0.017) or right stimulation (p<0.001), without significant perfusion differences between these two subgroups. These data show that distinct successful rTMS protocols induce equivalent brain functional changes associated to antidepressive efficiency, consisting to a remote brain limbic activity decrease within the left perirhinal cortex. However, these results will have to be confirmed in a double-blind randomized trial using a sham control group. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Computer-assisted superimposition of magnetic resonance and high-resolution technetium-99m-HMPAO and thallium-201 SPECT images of the brain

    SciTech Connect

    Holman, B.L.; Zimmerman, R.E.; Johnson, K.A.; Carvalho, P.A.; Schwartz, R.B.; Loeffler, J.S.; Alexander, E.; Pelizzari, C.A.; Chen, G.T. )

    1991-08-01

    A method for registering three-dimensional CT, MR, and PET data sets that require no special patient immobilization or other precise positioning measures was adapted to high-resolution SPECT and MRI and was applied in 14 subjects (five normal volunteers, four patients with dementia (Alzheimer's disease), two patients with recurrent glioblastoma, and three patients with focal lesions (stroke, arachnoid cyst and head trauma)). T2-weighted axial magnetic resonance images and transaxial 99mTc-HMPAO and 201Tl images acquired with an annular gamma camera were merged using an objective registration (translation, rotation and rescaling) program. In the normal subjects and patients with dementia and focal lesions, focal areas of high uptake corresponded to gray matter structures. Focal lesions observed on MRI corresponded to perfusion defects on SPECT. In the patients who had undergone surgical resection of glioblastoma followed by interstitial brachytherapy, increased 201Tl corresponding to recurrent tumor could be localized from the superimposed images. The method was evaluated by measuring the residuals in all subjects and translational errors due to superimposition of deep structures in the 12 subjects with normal thalamic anatomy and 99mTc-HMPAO uptake. This method for superimposing magnetic resonance and high-resolution SPECT images of the brain is a useful technique for correlating regional function with brain anatomy.

  9. PET and SPECT exploration of central monoaminergic transporters for the development of new drugs and treatments in brain disorders.

    PubMed

    Guilloteau, D; Chalon, S

    2005-01-01

    Membrane and vesicular monoaminergic transporters, responsible for the homeostasis of neurotransmitter pools at nerve endings, are very involved in the physiology and diseases of central nervous system. Recent progresses of cerebral molecular imaging using SPECT and PET methods allow the extend of in vivo exploration of these transporters. For this aim, an increasing number of radiopharmaceuticals labelled with [123I], [99mTc], [11C] or [18F] have been developed such as cocaine derivatives for the DAT, compounds from the diphenyl sulfide family for the SERT, and dihydrotetrabenazine derivatives for the VMAT2. These functional imaging methods can be very useful in several neurological and psychiatric disorders which involve the monoaminergic neurotransmission systems such as Parkinson's disease, ADHD, depression and autism. For example, the DAT is a specific index of the density of dopaminergic endings which progressively degenerate in Parkinson's disease. In vivo exploration of this transporter can therefore be a relevant way (i) to realize an early detection of the loss of dopaminergic neurons, (ii) to assess the progression of the disease, (iii) to validate and improve the efficacy of new therapeutic strategies such as neuroprotection and neuroreparation. In all, the extend of in vivo exploration of monoamine transporters will allow great progress for (1) knowledge of physiopathological mechanisms of brain disorders, (2) early diagnosis of cerebral dysfunctions, allowing early use of new therapies, (3) selection of homogenous classes of subjects for therapeutic assays, (4) objectiveness of drug-molecular target interaction, (5) follow-up of disease evolution and treatment.

  10. Brain MRI, Tc-99m HMPAO SPECT and F-18 FP-CIT PET/CT Findings in a Patient with Wilson Disease: A Case Report.

    PubMed

    Kim, Seungyoo; Song, In Uk; Chung, Yong An; Choi, Eun Kyung; Oh, Jin Kyoung

    2014-12-01

    A 34-year-old female had experienced head and hand tremors with a dystonic component for 8 months. Brain MRI showed T2 high signal intensity in the periaqueductal region, dorsal midbrain and dorsal upper pons. No abnormal uptake was noted on Tc-99m HMPAO SPECT or F-18 FP-CIT PET/CT. Wilson disease was diagnosed according to the 2008 consensus guideline from the American Association for the Study of Liver Disease and 2012 guideline from the European Association for the Study of the Liver. This case demonstrates T2 signal change in the basal ganglia, excluding the putamen, in a Wilson disease patient with relatively severe clinical findings, but normal Tc-99m HMPAO SPECT and F-18 FP-CIT PET/CT.

  11. Combination of blood flow asymmetry in the cerebral and cerebellar hemispheres on brain perfusion SPECT predicts 5-year outcome in patients with symptomatic unilateral major cerebral artery occlusion.

    PubMed

    Nomura, Jun-ichi; Ogasawara, Kuniaki; Saito, Hideo; Terasaki, Kazunori; Matsumoto, Yoshiyasu; Takahashi, Yoshihiro; Ogasawara, Yasushi; Saura, Hiroaki; Yoshida, Koji; Sato, Yuiko; Kubo, Yoshitaka; Ogawa, Akira

    2014-03-01

    Misery perfusion increases the risk of stroke recurrence in patients with symptomatic major cerebral artery occlusion. The ratio of brain perfusion contralateral-to-affected asymmetry in the cerebellar hemisphere to brain perfusion affected-to-contralateral asymmetry in the cerebral hemisphere (CblPR/CbrPR) indicates affected-to-contralateral asymmetry of oxygen extraction fraction (OEF) in the cerebral hemisphere. The purpose of the present study was to determine whether the CblPR/CbrPR on brain perfusion single-photon emission computed tomography (SPECT) predicts 5-year outcomes in patients with symptomatic unilateral occlusion of the middle cerebral artery (MCA) or internal carotid artery (ICA). Brain perfusion was assessed using N-isopropyl-p-[123I]-iodoamphetamine (123I-IMP) SPECT in 70 patients. A region of interest (ROI) was manually placed in the bilateral MCA territories and in the bilateral cerebellar hemispheres, and the CblPR/CbrPR was calculated. All patients were prospectively followed for 5 years. The primary end points were stroke recurrence or death. A total of 17 patients exhibited the primary end points, 11 of whom experienced subsequent ipsilateral strokes. Multivariate analysis revealed that only high CblPR/CbrPR was significantly associated with the development of the primary end point or subsequent ipsilateral strokes (95% confidential limits [CIs], 1.130-3.145; P  =  0.0114 or 95% CIs, 2.558-5.140; P  =  0.0045, respectively). The CblPR/CbrPR provided 65% (11/17) or 91% (10/11) sensitivity and 88% (47/53) or 88% (52/59) specificity in predicting the primary end point or subsequent ipsilateral strokes, respectively. The CblPR/CbrPR on brain perfusion SPECT predicts 5-year outcomes in patients with symptomatic unilateral occlusion of the MCA or ICA.

  12. Tl-201 brain SPECT imaging in preoperative supratentorial glioma: Is it useful in the grading of nonehancing CT or MRI lesions?

    SciTech Connect

    Ryu, J.S.; Moon, D.H.; Lee, H.K.

    1995-05-01

    Contrast enhanced MRI is valuable in predicting the histologic grade of gliomas. However, some high grade tumors may not demonstrate any significant enhancement. The purpose of this study was to assess the contribution of Tl-201 brain SPECT in the grading of preoperative glioma and the correlation with contrast enhancement in MRI or CT. The subjects consisted of 30 patients(pts) with suspected gliomas on contrast enhanced MR(n=27) or CT(n=3). Tl-201 brain SPECT was performed after injection of 74MBq of Tl-201 using triple head SPECT system. To quantify Tl-201 uptake, Tl indices (Tl average pixel counts of tumor ROl/normal contralateral hemisphere) were obtained. Histologic diagnoses were glioblastoma multiforme(GM) in 13, asrtrocytoma grade III (GIII) in 7, astrocytoma grade II(GII) in 6 and reactive gliosis(RG) in 4. All 13 pts with GM showed positive Tl-201 uptake(mean Tl; 9.0 {plus_minus}4.7), when Tl over 2.5 was considered as positive. Four of the 7 pts with GIII were positive(Tl: 4.6 {approximately}8.5) and the other 3 pts were negative. Tl-201 uptake(Tl; 0.8{approximately}1.5). All with GII showed negative Tl-201 uptake except one with 4.7 of Tl. Three of the 4 pts with RG also showed negative Tl-201 uptake and one showed positive uptake(Tl; 4.9). Overall sensitivity and specificity of Tl-201 SPECT in differentiating high grade glioma were 85% and 80%. In the correlation with contrast enhancement in MRI or CT, all nonenhancing lesions were negative Tl-201 uptake including 2 lesions with GIII. Nineteen out of the 23 pts with enhancing lesions had positive Tl-201 uptake. Three pts with RG and one with GIII who had enhancing lesions in MRI showed negative Tl-201 uptake. In conclusion, Tl-201 brain SPECT imaging is a useful method in differentiating the high grade gliomas in contrast enhancing lesions in MRI or CT. It has no additional value in differential diagnosis of nonenhancing lesions.

  13. Towards mapping the brain connectome in depression: functional connectivity by perfusion SPECT.

    PubMed

    Gardner, Ann; Åstrand, Disa; Öberg, Johanna; Jacobsson, Hans; Jonsson, Cathrine; Larsson, Stig; Pagani, Marco

    2014-08-30

    Several studies have demonstrated altered brain functional connectivity in the resting state in depression. However, no study has investigated interregional networking in patients with persistent depressive disorder (PDD). The aim of this study was to assess differences in brain perfusion distribution and connectivity between large groups of patients and healthy controls. Participants comprised 91 patients with PDD and 65 age- and sex-matched healthy controls. Resting state perfusion was investigated by single photon emission computed tomography, and group differences were assessed by Statistical Parametric Mapping. Brain connectivity was explored through a voxel-wise interregional correlation analysis using as covariate of interest the normalized values of clusters of voxels in which perfusion differences were found in group analysis. Significantly increased regional brain perfusion distribution covering a large part of the cerebellum was observed in patients as compared with controls. Patients showed a significant negative functional connectivity between the cerebellar cluster and caudate, bilaterally. This study demonstrated inverse relative perfusion between the cerebellum and the caudate in PDD. Functional uncoupling may be associated with a dysregulation between the role of the cerebellum in action control and of the caudate in action selection, initiation and decision making in the patients. The potential impact of the resting state condition and the possibility of mitochondrial impairment are discussed. Copyright © 2014 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  14. Glioma residual or recurrence versus radiation necrosis: accuracy of pentavalent technetium-99m-dimercaptosuccinic acid [Tc-99m (V) DMSA] brain SPECT compared to proton magnetic resonance spectroscopy (1H-MRS): initial results.

    PubMed

    Amin, Amr; Moustafa, Hosna; Ahmed, Ebaa; El-Toukhy, Mohamed

    2012-02-01

    We compared pentavalent technetium-99m dimercaptosuccinic acid (Tc-99m (V) DMSA) brain single photon emission computed tomography (SPECT) and proton magnetic resonance spectroscopy ((1)H-MRS) for the detection of residual or recurrent gliomas after surgery and radiotherapy. A total of 24 glioma patients, previously operated upon and treated with radiotherapy, were studied. SPECT was acquired 2-3 h post-administration of 555-740 MBq of Tc-99m (V) DMSA. Lesion to normal (L/N) delayed uptake ratio was calculated as: mean counts of tumor ROI (L)/mean counts of normal mirror symmetric ROI (N). (1)H-MRS was performed using a 1.5-T scanner equipped with a spectroscopy package. SPECT and (1)H-MRS results were compared with pathology or follow-up neuroimaging studies. SPECT and (1)H-MRS showed concordant residue or recurrence in 9/24 (37.5%) patients. Both were true negative in 6/24 (25%) patients. SPECT and (1)H-MRS disagreed in 9 recurrences [7/9 (77.8%) and 2/9 (22.2%) were true positive by SPECT and (1)H-MRS, respectively]. Sensitivity of SPECT and (1)H-MRS in detecting recurrence was 88.8 and 61.1% with accuracies of 91.6 and 70.8%, respectively. A positive association between the delayed L/N ratio and tumor grade was found; the higher the grade, the higher is the L/N ratio (r = 0.62, P = 0.001). Tc-99m (V) DMSA brain SPECT is more accurate compared to (1)H-MRS for the detection of tumor residual tissues or recurrence in glioma patients with previous radiotherapy. It allows early and non-invasive differentiation of residual tumor or recurrence from irradiation necrosis.

  15. Brain perfusion SPECT imaging and acetazolamide challenge in vascular cognitive impairment.

    PubMed

    Farid, Karim; Petras, Slavomir; Ducasse, Valérie; Chokron, Sylvie; Helft, Gérard; Blacher, Jacques; Caillat-Vigneron, Nadine

    2012-06-01

    Cerebrovascular disease is recognized as a common cause of cognitive impairment and dementia, alone or coexisting with other neurodegenerative diseases, mostly Alzheimer's disease. Vascular cognitive impairment (VCI) is a part of the heterogenous disorders group related to cerebral vessel disease. Although age is one of the most important risk factors for VCI, other common cardiovascular risk factors are also involved. By investigating these risk factors, a high proportion of these cognitive disorders can be prevented and/or delayed. Until now, only treatment of midlife arterial hypertension has been recognized as a preventing factor of vascular dementia. Brain MRI is becoming the method of choice to investigate cerebral vascular pathologies. However, this form of morphological imaging remains inadequate and does not provide useful functional information during VCI exploration, despite which functional imaging such as brain perfusion single-photon computed tomography, performed in baseline conditions and/or after an acetazolamide challenge, is underutilized in VCI exploration. The common strategies for VCI screening have not been standardized until now, and therefore further long-term imaging studies are needed to establish early diagnostic protocols. The present review summarizes the potential benefits of brain perfusion single-photon computed tomography imaging and possible scintigraphic quantification of cerebral hemodynamic reserves in investigation of VCI.

  16. Receptor binding characterization of the benzodiazepine radioligand sup 125 I-Ro16-0154: Potential probe for SPECT (Single Photon Emission Computed Tomography) brain imaging

    SciTech Connect

    Johnson, E.W.; Woods, S.W.; Zoghbi, S.; Baldwin, R.M.; Innis, R.B. ); McBride, B.J. )

    1990-01-01

    The binding of an iodinated benzodiazepine (BZ) radioligand has been characterized, particularly in regard to its potential use as a neuroreceptor brain imaging agent with SPECT (Single Photon Emission Computed Tomography). Ro16-0154 is an iodine-containing BZ antagonist and a close analog of Ro15-1788. In tissue homogenates prepared from human and monkey brain, the binding of {sup 125}I-labeled Ro16-0154 was saturable, of high affinity, and had high ratios of specific to non-specific binding. Physiological concentrations of NaCl enhanced specific binding approximately 15% compared to buffer without this salt. Kinetic studies of association and dissociation demonstrated a temperature dependent decrease in affinity with increasing temperature. Drug displacement studies confirmed that {sup 125}I-Ro16-0154 binds to the central type BZ receptor: binding is virtually identical to that of {sup 3}H-Ro15-1788 except that {sup 125}I-Ro16-0154 shows an almost 10 fold higher affinity at 37{degree}C. These in vitro results suggest that {sup 123}I-labeled Ro16-0154 shows promise as a selective, high affinity SPECT probe of the brain's BZ receptor.

  17. SPECT assessment of brain activation induced by caffeine: no effect on areas involved in dependence.

    PubMed

    Nehlig, Astrid; Armspach, Jean-Paul; Namer, Izzie J

    2010-01-01

    Caffeine is not considered addictive, and in animals it does not trigger metabolic increases or dopamine release in brain areas involved in reinforcement and reward. Our objective was to measure caffeine effects on cerebral perfusion in humans using single photon emission computed tomography with a specific focus on areas of reinforcement and reward. Two groups of nonsmoking subjects were studied, one with a low (8 subjects) and one with a high (6 subjects) daily coffee consumption. The subjects ingested 3 mg/kg caffeine or placebo in a raspberry-tasting drink, and scans were performed 45 min after ingestion. A control group of 12 healthy volunteers receiving no drink was also studied. Caffeine consumption led to a generalized, statistically nonsignificant perfusion decrease of 6% to 8%, comparable in low and high consumers. Compared with controls, low consumers displayed neuronal activation bilaterally in inferior frontal gyrus-anterior insular cortex and uncus, left internal parietal cortex, right lingual gyrus, and cerebellum. In high consumers, brain activation occurred bilaterally only in hypothalamus. Thus, on a background of widespread low-amplitude perfusion decrease, caffeine activates a few regions mainly involved in the control of vigilance, anxiety, and cardiovascular regulation, but does not affect areas involved in reinforcing and reward.

  18. SPECT assessment of brain activation induced by caffeine: no effect on areas involved in dependence

    PubMed Central

    Nehlig, Astrid; Armspach, Jean-Paul; Namer, Izzie J.

    2010-01-01

    Caffeine is not considered addictive, and in animals it does not trigger metabolic increases or dopamine release in brain areas involved in reinforcement and reward. Our objective was to measure caffeine effects on cerebral perfusion in humans using single photon emission computed tomography, with a specific focus on areas of reinforcement and reward. Two groups of nonsmoking subjects were studied, one with a low (8 subjects) and one with a high (6 subjects) daily coffee consumption. The subjects ingested 3 mg/kg caffeine or placebo in a raspberry-tasting drink, and scans were performed 45 min after ingestion. A control group of 12 healthy volunteers receiving no drink was also studied. Caffeine consumption led to a generalized, statistically nonsignificant perfusion decrease of 6% to 8%, comparable in low and high consumers. Compared with controls, low consumers displayed neuronal activation bilaterally in inferior frontal gyrusanterior insular cortex and uncus, left internal parietal cortex, right lingual gyrus, and cerebellum. In high consumers, brain activation occurred bilaterally only in hypothalamus. Thus, on a background of widespread low-amplitude perfusion decrease, caffeine activates a few regions mainly involved in the control of vigilance, anxiety, and cardiovascular regulation, but does not affect areas involved in reinforcing and reward. PMID:20623930

  19. Adaptive SPECT

    PubMed Central

    Barrett, Harrison H.; Furenlid, Lars R.; Freed, Melanie; Hesterman, Jacob Y.; Kupinski, Matthew A.; Clarkson, Eric; Whitaker, Meredith K.

    2008-01-01

    Adaptive imaging systems alter their data-acquisition configuration or protocol in response to the image information received. An adaptive pinhole single-photon emission computed tomography (SPECT) system might acquire an initial scout image to obtain preliminary information about the radiotracer distribution and then adjust the configuration or sizes of the pinholes, the magnifications, or the projection angles in order to improve performance. This paper briefly describes two small-animal SPECT systems that allow this flexibility and then presents a framework for evaluating adaptive systems in general, and adaptive SPECT systems in particular. The evaluation is in terms of the performance of linear observers on detection or estimation tasks. Expressions are derived for the ideal linear (Hotelling) observer and the ideal linear (Wiener) estimator with adaptive imaging. Detailed expressions for the performance figures of merit are given, and possible adaptation rules are discussed. PMID:18541485

  20. sup 123 I-iodoamphetamine SPECT brain imaging in alternating hemiplegia

    SciTech Connect

    Zupanc, M.L.; Dobkin, J.A.; Perlman, S.B. )

    1991-01-01

    Alternating hemiplegia of childhood is an unusual disorder characterized by early onset (occurring before 18 months of age); repeated attacks of hemiplegia involving both sides of the body; other paroxysmal phenomena, such as tonic stiffening, dystonic posturing, choreoathetoid movements, ocular motor abnormalities, and autonomic disturbances, in association with bouts of hemiplegia or occurring independently; and evidence of mental or neurologic deficits. A girl was examined because of left hemiplegia at the age of 16 months. The patient had begun exhibiting episodes of alternating hemiplegia at approximately 4 months of age. They consisted of tonic stiffening and dystonia of the right or left extremities, lasting from 30 min to several hours and followed by residual hemiparesis. They were invariably accompanied by ocular motor abnormalities. Magnetic resonance imaging, computed tomography, and angiography all were normal. Single proton emission computed tomography brain images during an acute episode of right hemiplegia demonstrated hypoperfusion of the left cerebral hemisphere. Following improvement of the hemiplegia, the patient was re-evaluated. The uptake of the radiotracer in the left hemisphere was increased. The scan did not demonstrate significant asymmetry in cerebral perfusion.

  1. Modified total variation norm for the maximum a posteriori ordered subsets expectation maximization reconstruction in fan-beam SPECT brain perfusion imaging

    NASA Astrophysics Data System (ADS)

    Krol, Andrzej; Yang, Zhaoxia; Xu, Yuesheng; Wismüller, Axel; Feiglin, David H.

    2011-03-01

    The anisotropic geometry of Fan-Beam Collimator (FBC) Single Photon Emission Tomography (SPECT) is used in brain perfusion imaging with clinical goals to quantify regional cerebral blood flow and to accurately determine the location and extent of the brain perfusion defects. One of the difficult issues that need to be addressed is partial volume effect. The purpose of this study was to minimize the partial volume effect while preserving the optimal tradeoff between noise and bias, and maintaining spatial resolution in the reconstructed images acquired in FBC geometry. We modified conventional isotropic TV (L1) norm, which has only one hyperparameter, and replaced it with two independent TV (L1u) norms (TVxy and TVz) along two orthogonal basis vectors (XY, Z) in 3D reconstruction space. We investigated if the anisotropic norm with two hyperparameters (βxy and βz, where z is parallel to the axis-of-rotation) performed better in FBC-SPECT reconstruction, as compared to the conventional isotropic norm with one hyperparameter (β) only. We found that MAP-OSEM reconstruction with modified TV norm produced images with smaller partial volume effect, as compared to the conventional TV norm at a cost of slight increase in the bias and noise.

  2. Analysis of SPECT brain images for the diagnosis of Alzheimer's disease based on NMF for feature extraction.

    PubMed

    Padilla, P; Górriz, J M; Ramírez, J; Lang, E W; Chaves, R; Segovia, F; López, M; Salas-González, D; Alvarez, I

    2010-08-02

    This letter presents a novel computer-aided diagnosis (CAD) technique for the early diagnosis of Alzheimer's disease (AD) based on non-negative matrix factorization (NMF) analysis applied to single photon emission computed tomography (SPECT) images. A baseline normalized SPECT database containing normalized data for both AD patients and healthy reference patients is selected for this study. The SPECT database is analyzed by applying the Fisher discriminant ratio (FDR) for feature selection and NMF for feature extraction of relevant components of each subject. The main goal of these preprocessing steps is to reduce the large dimensionality of the input data and to relieve the so called "curse of dimensionality" problem. The resulting NMF-transformed set of data, which contains a reduced number of features, is classified by means of a support vector machines based classification technique (SVM). The proposed NMF + SVM method yields up to 94% classification accuracy, with high sensitivity and specificity values (upper than 90%), becoming an accurate method for SPECT image classification. For the sake of completeness, comparison between another recently developed principal component analysis (PCA) plus SVM method and the proposed method is also provided, yielding results for the NMF + SVM approach that outperform the behavior of the reference PCA + SVM or conventional voxel-as-feature (VAF) plus SVM methods.

  3. A Standardized Method for the Construction of Tracer Specific PET and SPECT Rat Brain Templates: Validation and Implementation of a Toolbox

    PubMed Central

    Vállez Garcia, David; Casteels, Cindy; Schwarz, Adam J.; Dierckx, Rudi A. J. O.; Koole, Michel; Doorduin, Janine

    2015-01-01

    High-resolution anatomical image data in preclinical brain PET and SPECT studies is often not available, and inter-modality spatial normalization to an MRI brain template is frequently performed. However, this procedure can be challenging for tracers where substantial anatomical structures present limited tracer uptake. Therefore, we constructed and validated strain- and tracer-specific rat brain templates in Paxinos space to allow intra-modal registration. PET [18F]FDG, [11C]flumazenil, [11C]MeDAS, [11C]PK11195 and [11C]raclopride, and SPECT [99mTc]HMPAO brain scans were acquired from healthy male rats. Tracer-specific templates were constructed by averaging the scans, and by spatial normalization to a widely used MRI-based template. The added value of tracer-specific templates was evaluated by quantification of the residual error between original and realigned voxels after random misalignments of the data set. Additionally, the impact of strain differences, disease uptake patterns (focal and diffuse lesion), and the effect of image and template size on the registration errors were explored. Mean registration errors were 0.70±0.32mm for [18F]FDG (n = 25), 0.23±0.10mm for [11C]flumazenil (n = 13), 0.88±0.20 mm for [11C]MeDAS (n = 15), 0.64±0.28mm for [11C]PK11195 (n = 19), 0.34±0.15mm for [11C]raclopride (n = 6), and 0.40±0.13mm for [99mTc]HMPAO (n = 15). These values were smallest with tracer-specific templates, when compared to the use of [18F]FDG as reference template (p&0.001). Additionally, registration errors were smallest with strain-specific templates (p&0.05), and when images and templates had the same size (p≤0.001). Moreover, highest registration errors were found for the focal lesion group (p&0.005) and the diffuse lesion group (p = n.s.). In the voxel-based analysis, the reported coordinates of the focal lesion model are consistent with the stereotaxic injection procedure. The use of PET/SPECT strain- and tracer-specific templates allows

  4. Clinical Comparison of 99mTc Exametazime and 123I Ioflupane SPECT in Patients with Chronic Mild Traumatic Brain Injury

    PubMed Central

    Newberg, Andrew B.; Serruya, Mijail; Gepty, Andrew; Intenzo, Charles; Lewis, Todd; Amen, Daniel; Russell, David S.; Wintering, Nancy

    2014-01-01

    Background This study evaluated the clinical interpretations of single photon emission computed tomography (SPECT) using a cerebral blood flow and a dopamine transporter tracer in patients with chronic mild traumatic brain injury (TBI). The goal was to determine how these two different scan might be used and compared to each other in this patient population. Methods and Findings Twenty-five patients with persistent symptoms after a mild TBI underwent SPECT with both 99mTc exametazime to measure cerebral blood flow (CBF) and 123I ioflupane to measure dopamine transporter (DAT) binding. The scans were interpreted by two expert readers blinded to any case information and were assessed for abnormal findings in comparison to 10 controls for each type of scan. Qualitative CBF scores for each cortical and subcortical region along with DAT binding scores for the striatum were compared to each other across subjects and to controls. In addition, symptoms were compared to brain scan findings. TBI patients had an average of 6 brain regions with abnormal perfusion compared to controls who had an average of 2 abnormal regions (p<0.001). Patient with headaches had lower CBF in the right frontal lobe, and higher CBF in the left parietal lobe compared to patients without headaches. Lower CBF in the right temporal lobe correlated with poorer reported physical health. Higher DAT binding was associated with more depressive symptoms and overall poorer reported mental health. There was no clear association between CBF and DAT binding in these patients. Conclusions Overall, both scans detected abnormalities in brain function, but appear to reflect different types of physiological processes associated with chronic mild TBI symptoms. Both types of scans might have distinct uses in the evaluation of chronic TBI patients depending on the clinical scenario. PMID:24475210

  5. 99mTc-ECD brain perfusion SPECT imaging for the assessment of brain perfusion in cerebral palsy (CP) patients with evaluation of the effect of hyperbaric oxygen therapy.

    PubMed

    Asl, Mina Taghizadeh; Yousefi, Farzaneh; Nemati, Reza; Assadi, Majid

    2015-01-01

    The present study was carried out to evaluate cerebral perfusion in different types of cerebral palsy (CP) patients. For those patients who underwent hyperbaric oxygen therapy, brain perfusion before and after the therapy was compared. A total of 11 CP patients were enrolled in this study, of which 4 patients underwent oxygen therapy. Before oxygen therapy and at the end of 40 sessions of oxygen treatment, 99mTc-ECD brain perfusion single photon emission computed tomography (SPECT) was performed , and the results were compared. A total of 11 CP patients, 7 females and 4 males with an age range of 5-27 years participated in the study. In brain SPECT studies, all the patients showed perfusion impairments. The region most significantly involved was the frontal lobe (54.54%), followed by the temporal lobe (27.27%), the occipital lobe (18.18%), the visual cortex (18.18%), the basal ganglia (9.09%), the parietal lobe (9.09%), and the cerebellum (9.09%). Frontal-lobe hypoperfusion was seen in all types of cerebral palsy. Two out of 4 patients (2 males and 2 females) who underwent oxygen therapy revealed certain degree of brain perfusion improvement. This study demonstrated decreased cerebral perfusion in different types of CP patients. The study also showed that hyperbaric oxygen therapy improved cerebral perfusion in a few CP patients. However, it could keep the physiological discussion open and strenghten a link with other areas of neurology in which this approach may have some value.

  6. Performance of a high-sensitivity dedicated cardiac SPECT scanner for striatal uptake quantification in the brain based on analysis of projection data

    PubMed Central

    Park, Mi-Ae; Moore, Stephen C.; Müller, Stefan P.; McQuaid, Sarah J.; Kijewski, Marie Foley

    2013-01-01

    Purpose: The authors have previously reported the advantages of high-sensitivity single-photon emission computed tomography (SPECT) systems for imaging structures located deep inside the brain. DaTscan (Isoflupane I-123) is a dopamine transporter (DaT) imaging agent that has shown potential for early detection of Parkinson disease (PD), as well as for monitoring progression of the disease. Realizing the full potential of DaTscan requires efficient estimation of striatal uptake from SPECT images. They have evaluated two SPECT systems, a conventional dual-head gamma camera with low-energy high-resolution collimators (conventional) and a dedicated high-sensitivity multidetector cardiac imaging system (dedicated) for imaging tasks related to PD. Methods: Cramer–Rao bounds (CRB) on precision of estimates of striatal and background activity concentrations were calculated from high-count, separate acquisitions of the compartments (right striata, left striata, background) of a striatal phantom. CRB on striatal and background activity concentration were calculated from essentially noise-free projection datasets, synthesized by scaling and summing the compartment projection datasets, for a range of total detected counts. They also calculated variances of estimates of specific-to-nonspecific binding ratios (BR) and asymmetry indices from these values using propagation of error analysis, as well as the precision of measuring changes in BR on the order of the average annual decline in early PD. Results: Under typical clinical conditions, the conventional camera detected 2 M counts while the dedicated camera detected 12 M counts. Assuming a normal BR of 5, the standard deviation of BR estimates was 0.042 and 0.021 for the conventional and dedicated system, respectively. For an 8% decrease to BR = 4.6, the signal-to-noise ratio were 6.8 (conventional) and 13.3 (dedicated); for a 5% decrease, they were 4.2 (conventional) and 8.3 (dedicated). Conclusions: This implies that PD can

  7. Performance of a high-sensitivity dedicated cardiac SPECT scanner for striatal uptake quantification in the brain based on analysis of projection data

    SciTech Connect

    Park, Mi-Ae; Moore, Stephen C.; McQuaid, Sarah J.; Kijewski, Marie Foley; Mueller, Stefan P.

    2013-04-15

    Purpose: The authors have previously reported the advantages of high-sensitivity single-photon emission computed tomography (SPECT) systems for imaging structures located deep inside the brain. DaTscan (Isoflupane I-123) is a dopamine transporter (DaT) imaging agent that has shown potential for early detection of Parkinson disease (PD), as well as for monitoring progression of the disease. Realizing the full potential of DaTscan requires efficient estimation of striatal uptake from SPECT images. They have evaluated two SPECT systems, a conventional dual-head gamma camera with low-energy high-resolution collimators (conventional) and a dedicated high-sensitivity multidetector cardiac imaging system (dedicated) for imaging tasks related to PD. Methods: Cramer-Rao bounds (CRB) on precision of estimates of striatal and background activity concentrations were calculated from high-count, separate acquisitions of the compartments (right striata, left striata, background) of a striatal phantom. CRB on striatal and background activity concentration were calculated from essentially noise-free projection datasets, synthesized by scaling and summing the compartment projection datasets, for a range of total detected counts. They also calculated variances of estimates of specific-to-nonspecific binding ratios (BR) and asymmetry indices from these values using propagation of error analysis, as well as the precision of measuring changes in BR on the order of the average annual decline in early PD. Results: Under typical clinical conditions, the conventional camera detected 2 M counts while the dedicated camera detected 12 M counts. Assuming a normal BR of 5, the standard deviation of BR estimates was 0.042 and 0.021 for the conventional and dedicated system, respectively. For an 8% decrease to BR = 4.6, the signal-to-noise ratio were 6.8 (conventional) and 13.3 (dedicated); for a 5% decrease, they were 4.2 (conventional) and 8.3 (dedicated). Conclusions: This implies that PD can

  8. Correction for scatter and septal penetration using convolution subtraction methods and model-based compensation in 123I brain SPECT imaging-a Monte Carlo study.

    PubMed

    Larsson, Anne; Ljungberg, Michael; Mo, Susanna Jakobson; Riklund, Katrine; Johansson, Lennart

    2006-11-21

    Scatter and septal penetration deteriorate contrast and quantitative accuracy in single photon emission computed tomography (SPECT). In this study four different correction techniques for scatter and septal penetration are evaluated for 123I brain SPECT. One of the methods is a form of model-based compensation which uses the effective source scatter estimation (ESSE) for modelling scatter, and collimator-detector response (CDR) including both geometric and penetration components. The other methods, which operate on the 2D projection images, are convolution scatter subtraction (CSS) and two versions of transmission dependent convolution subtraction (TDCS), one of them proposed by us. This method uses CSS for correction for septal penetration, with a separate kernel, and TDCS for scatter correction. The corrections are evaluated for a dopamine transporter (DAT) study and a study of the regional cerebral blood flow (rCBF), performed with 123I. The images are produced using a recently developed Monte Carlo collimator routine added to the program SIMIND which can include interactions in the collimator. The results show that the method included in the iterative reconstruction is preferable to the other methods and that the new TDCS version gives better results compared with the other 2D methods.

  9. Correction for scatter and septal penetration using convolution subtraction methods and model-based compensation in 123I brain SPECT imaging—a Monte Carlo study

    NASA Astrophysics Data System (ADS)

    Larsson, Anne; Ljungberg, Michael; Jakobson Mo, Susanna; Riklund, Katrine; Johansson, Lennart

    2006-11-01

    Scatter and septal penetration deteriorate contrast and quantitative accuracy in single photon emission computed tomography (SPECT). In this study four different correction techniques for scatter and septal penetration are evaluated for 123I brain SPECT. One of the methods is a form of model-based compensation which uses the effective source scatter estimation (ESSE) for modelling scatter, and collimator-detector response (CDR) including both geometric and penetration components. The other methods, which operate on the 2D projection images, are convolution scatter subtraction (CSS) and two versions of transmission dependent convolution subtraction (TDCS), one of them proposed by us. This method uses CSS for correction for septal penetration, with a separate kernel, and TDCS for scatter correction. The corrections are evaluated for a dopamine transporter (DAT) study and a study of the regional cerebral blood flow (rCBF), performed with 123I. The images are produced using a recently developed Monte Carlo collimator routine added to the program SIMIND which can include interactions in the collimator. The results show that the method included in the iterative reconstruction is preferable to the other methods and that the new TDCS version gives better results compared with the other 2D methods.

  10. [Evaluation by statistical brain perfusion SPECT analysis on MRI findings, kana pick-out test and Mini-Mental State Examination results in patients with forgetfulness].

    PubMed

    Nakatsuka, Hiroki; Matsubara, Ichirou; Ohtani, Haruhiko

    2003-04-01

    The aim of this single photon emission computed tomography(SPECT) study was to determine the abnormality of the regional cerebral blood flow(rCBF) using a three-dimensional stereotactic surface projection (3 D-SSP) in 18 patients who were referred to the hospital because of forgetfulness. Two intergroup comparison by 3 D-SSP analysis was conducted based on MRI, kana pick-out test and Mini-Mental State Examination (MMSE) results. Of the MRI findings, in the brain atrophy group, rCBF was decreased in the posterior cingulate gyrus, medial temporal structure and parieto-temporal association cortex; these rCBF-decreased areas are similar to the Alzheimer disease pattern. In the group where the MMSE was normal but the kana pick-out test was abnormal, rCBF was decreased in the posterior cingulate gyrus and cinguloparietal transitional area. In the group where both the MMSE and kana pick-out test were abnormal, rCBF was decreased in the parieto-temporal association cortex, temporal cortex and medial temporal structure. These results suggest that 3 D-SSP analysis of the SPECT with MMSE and the kana pick-out test provides the possibility of early diagnosis of initial stage of Alzheimer's disease.

  11. Thrombotic Thrombocytopenic Purpura with Reversible Neurological Features: Brain Diffusion MRI with ADC Map, Spect and EEG Findings. A Case Report.

    PubMed

    Yerdelen, D; Göksel, B K; Yıldırım, T; Karataş, M; Karaca, S; Reyhan, M; Ozdoğu, H

    2006-11-30

    Although nervous system involvement is common in thrombotic thrombocytopenic purpura (TTP), abnormalities on computerized tomography, magnetic resonance imaging and electroencephalography are not encountered so frequently and if present, these abnormalities are often reversible. We describe a 39-year-old woman with recurring transient focal neurological findings found to have laboratory findings consistent with TTP. In cerebral diffusion weighted images (DWI), diffuse cortical hyperintensity was noted in right frontal lobe, but the ADC (apparent diffusion coefficient) map was normal. Electroencephalography demonstrated lateralized slowing and repeated DWI showed diffuse cortical hyperintensity in the right hemisphere. SPECT showed luxury perfusion in the right hemisphere areas. The patient's condition resolved with plasmapheresis. Our patient illustrates that diffuse hemispheric involvement can be seen in DWI and EEG, and SPECT may show luxury perfusion after resolution of neurological findings in TTP cases. To our knowledge, this is the first TTP case in which the ADC map was normal.

  12. Monte Carlo simulation of scintillation photons for the design of a high-resolution SPECT detector dedicated to human brain.

    PubMed

    Hirano, Yoshiyuki; Zeniya, Tsutomu; Iida, Hidehiro

    2012-04-01

    In a typical single photon emission computed tomography (SPECT) system, intrinsic spatial resolution depends on the accuracy of the identification of an interacting point, which is dominated by propagation of the scintillation photons in the detector block. This study was intended to establish a Monte Carlo simulation-based evaluation tool taking into account the propagation of scintillation photons to estimate the intrinsic spatial and energy resolutions of the position-sensitive scintillator block in a SPECT detector. We employed Geant4 Monte Carlo simulation library which incorporated the optical photon processes for two different designs of the position-sensitive scintillator blocks. The validation of the simulation code was performed for a monolithic NaI(Tl) scintillator (251 × 147 × 6.4 mm(3)) coupled to 15 flat-panel type multi-anode photo multiplier tubes (PMT) (H8500: Hamamatsu) and results were compared with those obtained experimentally. The code was then applied to a LaBr(3)(Ce) scintillator of 120 mm square with varied thicknesses for designing high-resolution detector. The simulation resulted in 2.6 mm full width at half maximum (FWHM) of spatial resolution and 9.0% FWHM of energy resolution for the NaI(Tl)-based detector, which were in a good agreement of the experimental results, i.e., 2.7 mm and 10%, respectively. These findings suggest that Geant4 simulation including optical photon processes enables to predict the spatial and energy resolutions of a SPECT detector block accurately. The simulation also demonstrated that 2 mm spatial resolution can be obtained for a 6 mm thickness of the LaBr(3)(Ce), which is a significant improvement in performance as compared to existing gamma camera system that employs the scintillation detector fitted with PMTs. The Monte Carlo simulation-based evaluation tool was established to estimate the intrinsic spatial and energy resolutions of SPECT detector with position sensitive PMTs. This simulation may

  13. Guidelines for brain radionuclide imaging. Perfusion single photon computed tomography (SPECT) using Tc-99m radiopharmaceuticals and brain metabolism positron emission tomography (PET) using F-18 fluorodeoxyglucose. The Belgian Society for Nuclear Medicine.

    PubMed

    Vander Borght, T; Laloux, P; Maes, A; Salmon, E; Goethals, I; Goldman, S

    2001-12-01

    The purpose of these guidelines is to assist nuclear medicine practitioners in recommending, performing, interpreting, and reporting the results of brain perfusion SPECT studies using Tc-99m radiopharmaceuticals and brain metabolism PET studies using F-18 fluorodeoxyglucose (FDG). These guidelines have been adapted and extended from those produced by the Society of Nuclear Medicine (Juni et al., 1998) and the European Association of Nuclear Medicine by a Belgian group of experts in the field trained in neurology and/or nuclear medicine. Some indications are not universally approved (e.g. brain death), but largely supported by the literature. They have been included in these guidelines in order to provide recommendations and a standardised protocol.

  14. Progress in BazookaSPECT.

    PubMed

    Miller, Brian W; Barber, H Bradford; Furenlid, Lars R; Moore, Stephen K; Barrett, Harrison H

    2009-01-01

    Recent progress on a high-resolution, photon-counting gamma-ray and x-ray imager called BazookaSPECT is presented. BazookaSPECT is an example of a new class of scintillation detectors based on integrating detectors such as CCD(charge-coupled device) or CMOS(complementary metal-oxide semiconductor) sensors. BazookaSPECT is unique in that it makes use of a scintillator in close proximity to a microchannel plate-based image intensifier for up-front optical amplification of scintillation light. We discuss progress made in bringing about compact BazookaSPECT modules and in real-time processing of event data using graphics processing units (GPUs). These advances are being implemented in the design of a high-resolution rodent brain imager called FastSPECT III. A key benefit of up-front optical gain is that any CCD/CMOS sensor can now be utilized for photon counting. We discuss the benefits and feasibility of using CMOS sensors as photon-counting detectors for digital radiography, with application in mammography and computed tomography (CT). We present as an appendix a formal method for comparing various photon-counting integrating detectors using objective statistical criteria.

  15. Progress in BazookaSPECT

    PubMed Central

    Miller, Brian W.; Barber, H. Bradford; Furenlid, Lars R.; Moore, Stephen K.; Barrett, Harrison H.

    2010-01-01

    Recent progress on a high-resolution, photon-counting gamma-ray and x-ray imager called BazookaSPECT is presented. BazookaSPECT is an example of a new class of scintillation detectors based on integrating detectors such as CCD(charge-coupled device) or CMOS(complementary metal-oxide semiconductor) sensors. BazookaSPECT is unique in that it makes use of a scintillator in close proximity to a microchannel plate-based image intensifier for up-front optical amplification of scintillation light. We discuss progress made in bringing about compact BazookaSPECT modules and in real-time processing of event data using graphics processing units (GPUs). These advances are being implemented in the design of a high-resolution rodent brain imager called FastSPECT III. A key benefit of up-front optical gain is that any CCD/CMOS sensor can now be utilized for photon counting. We discuss the benefits and feasibility of using CMOS sensors as photon-counting detectors for digital radiography, with application in mammography and computed tomography (CT). We present as an appendix a formal method for comparing various photon-counting integrating detectors using objective statistical criteria. PMID:21297897

  16. Hypoglycaemic hemiplegia: a repeat SPECT study.

    PubMed Central

    Shintani, S; Tsuruoka, S; Shiigai, T

    1993-01-01

    During a hypoglycaemic right hemiplegia induced by a deliberate overdose of oral hypoglycaemics, brain CT and angiography revealed no abnormalities. SPECTs made one day and six days later showed relative hypoperfusion in the left hemisphere. Repeat SPECT study suggested that the left hemisphere was more vulnerable than the right in the cerebral blood perfusion. This vulnerability might provoke the right hemiplegia in a critical condition, such as severe hypoglycaemia. Images PMID:8509788

  17. 99mTc-ECD brain perfusion SPECT imaging for the assessment of brain perfusion in cerebral palsy (CP) patients with evaluation of the effect of hyperbaric oxygen therapy

    PubMed Central

    Asl, Mina Taghizadeh; Yousefi, Farzaneh; Nemati, Reza; Assadi, Majid

    2015-01-01

    Objective: The present study was carried out to evaluate cerebral perfusion in different types of cerebral palsy (CP) patients. For those patients who underwent hyperbaric oxygen therapy, brain perfusion before and after the therapy was compared. Methods: A total of 11 CP patients were enrolled in this study, of which 4 patients underwent oxygen therapy. Before oxygen therapy and at the end of 40 sessions of oxygen treatment, 99mTc-ECD brain perfusion single photon emission computed tomography (SPECT) was performed , and the results were compared. Results: A total of 11 CP patients, 7 females and 4 males with an age range of 5-27 years participated in the study. In brain SPECT studies, all the patients showed perfusion impairments. The region most significantly involved was the frontal lobe (54.54%), followed by the temporal lobe (27.27%), the occipital lobe (18.18%), the visual cortex (18.18%), the basal ganglia (9.09%), the parietal lobe (9.09%), and the cerebellum (9.09%). Frontal-lobe hypoperfusion was seen in all types of cerebral palsy. Two out of 4 patients (2 males and 2 females) who underwent oxygen therapy revealed certain degree of brain perfusion improvement. Conclusion: This study demonstrated decreased cerebral perfusion in different types of CP patients. The study also showed that hyperbaric oxygen therapy improved cerebral perfusion in a few CP patients. However, it could keep the physiological discussion open and strenghten a link with other areas of neurology in which this approach may have some value. PMID:25785099

  18. [123I]beta-CIT SPECT demonstrates decreased brain dopamine and serotonin transporter levels in untreated parkinsonian patients.

    PubMed

    Haapaniemi, T H; Ahonen, A; Torniainen, P; Sotaniemi, K A; Myllylä, V V

    2001-01-01

    Striatal dopamine transporters (DATs) and serotonin transporters (SERTs) were evaluated in untreated patients with Parkinson's disease (PD) and controls using single-photon emission computed tomography (SPECT) with 2beta-carboxymethoxy-3beta-(4-iodophenyl)tropane ([123I]beta-CIT). The striatal DAT specific to non-displaceable uptake ratios of 29, and the SERT uptake measurements of 27, PD patients were compared with those of 21 and 16 controls, respectively. The results were correlated with Unified Parkinson's Disease Rating Scale (UPDRS) scores, the Hoehn & Yahr stage, age, duration of the disease, and the major PD signs. The specific DAT binding in the caudate, the putamen and the caudate/putamen ratio were measured. In all of the PD patients the striatal uptake values were bilaterally reduced, being 36.9% (P < 0.001) lower than those of the controls. In the hemiparkinsonian patients the reduction was greater on the side contralateral to the initial symptoms (33.3% vs. 27.8%) and the uptake ratios indicated a more pronounced deficit in the putamen (39.1%) than in the caudate (27.9%). The DAT uptake correlated with the UPDRS total score and activities of daily living (ADL) and motor subscores, the Hoehn & Yahr stage, and rigidity score. PD patients had significantly higher caudate to putamen ratios than the controls. In the PD patients the SERT values were lower in the thalamic and frontal regions. The SERT uptake ratio of the frontal area correlated with the UPDRS subscore I. [123I]beta-CIT SPECT provides a useful method for confirming the clinical diagnosis of PD with correlation to disease severity. Additionally, this technique allows the simultaneous measurement of SERT uptake and shows that PD patients, interestingly, seem to have decreased SERT availability in the thalamic and frontal areas.

  19. What are we changing with neurocognitive rehabilitation? Illustrations from two single cases of changes in neuropsychological performance and brain systems as measured by SPECT.

    PubMed

    Wykes, T

    1998-11-09

    If cognitive remediation is to be developed further, there have to be not only large-scale randomized trials but also detailed analysis of the strategies used to produce improved performance. In this study the strategies adopted by two people who took part in a remediation program are investigated, with their results on neuropsychological tasks and with concomitant brain image data gathered via SPECT while the participant was performing a Verbal Fluency task. After remediation there were improvements in many of the neuropsychological tests, and changes in the scan data. The changes in strategies and brain activation were different for both individuals. One person increased his verbal output but without close monitoring, so also increased his errors. The other participant decreased his output but monitored it more closely, and so decreased the errors. These strategies were reflected in the changes in activation between scans, i.e. increases in temporal areas for the increased output and bilateral decreases in the anterior cingulate and left pre-motor areas for the decreased output case. Together these results imply that the participants continue to use individual strategies which for many of the neuropsychological tasks produced gains. Further investigation of whether it is possible to change idiosyncratic strategy use is needed if we are to develop the efficacy of this remediation technique.

  20. Clinical value of the first dedicated, commercially available automatic injector for ictal brain SPECT in presurgical evaluation of pediatric epilepsy: comparison with manual injection.

    PubMed

    Kim, Sunhee; Holder, Deborah L; Laymon, Charles M; Tudorascu, Dana L; Deeb, Erin L; Panigrahy, Ashok; Mountz, James M

    2013-05-01

    The most challenging technical problem in ictal brain SPECT for localization of an epileptogenic focus is obtaining a timely injection of a radiopharmaceutical. In our institution, the first dedicated commercially available, remotely controlled automatic injector has been used in the pediatric epilepsy unit in conjunction with 24-h video and electroencephalogram monitoring. The goal of this study was to demonstrate the improved success rate of ictal injection by use of the automatic injector in the pediatric population. Eighty-four pediatric patients and eighty-four (99m)Tc-ethylcysteinate dimer ((99m)Tc-ECD) ictal brain SPECT studies were retrospectively analyzed in a masked manner. The group with manual injection consisted of 45 studies performed from 2004 to 2010 before the introduction of the automatic injector. The group with automatic injection consisted of 39 studies performed from 2010 to 2011 after the introduction of the automatic injector. The 2 groups were comparable in the total duration of seizure, injected dose, and time from the injection to the image acquisition. The latency time from the seizure onset to the initiation time of injection, the ratio of latency time to total duration of seizure (L/T), the number of patients with repeated studies, the number of days of additional hospitalization for each study, and the localization rate for identifying a single focus in each study were compared between the groups. The median latency time in the group with automatic injection (8 s) was significantly lower than that of the group with manual injection (18 s) (P < 0.05). Also there was a statistically significant decrease in the number of patients with repeated studies in the group with automatic injection (2/39 [5%]), compared with the group with manual injection (14/45 [31%]) (P < 0.05). The median number of days of additional hospitalization in the group with manual injection (range, 0-7) was statistically significantly different, compared with the

  1. I-123 Iofetamine SPECT scan in children with neurological disorders

    SciTech Connect

    Flamini, J.R.; Konkol, R.J.; Wells, R.G.; Sty, J.R. )

    1990-10-01

    I-123 Iofetamine (IMP) single photon emission computed tomography (SPECT) imaging of the brain in 42 patients (ages 14 days to 23 years) was compared with other localizing studies in children with neurological diseases. All had an EEG and at least one imaging study of the brain (computed tomography (CT) or magnetic resonance imaging (MRI), or both). Seventy-eight percent of the patients had an EEG within 24-72 hours of the IMP-SPECT scan. Thirty-five (83%) had a history of seizures, and the remainder had other neurological conditions without a history of seizures. In most cases, a normal EEG reading with normal CT or MRI result predicted a normal SPECT study. When the EEG was abnormal the majority of the IMP-SPECT scans were abnormal and localized the abnormality to the same region. A comparison with CT and MRI showed that structural abnormalities involving the cortex were usually well demonstrated with IMP-SPECT imaging. Structural lesions confined to the white matter were generally not detectable with IMP-SPECT. In a few cases, SPECT scans revealed abnormalities in deep brain areas not identified by EEG. IMP-SPECT imaging is a valuable technique for the detection and localization of abnormal cerebral metabolic activity in children with seizure disorders. A correlation with CT or MRI is essential for proper interpretation of abnormalities detected with IMP SPECT imaging.

  2. Comparison of two I-123 labeled SPECT probes, for the dopamine transporter in non-human primate brain

    SciTech Connect

    Gandelman, M.S.; Scanley, B.E.; Al-Tikrite, M.S.

    1994-05-01

    A comparative SPECT evaluation of the regional uptake of 28-carboisopropoxy-3{beta}-(4-iodophenyl)tropane (IP-CIT) and 2{beta}-carbomethoxy-3{beta}-(4-iodophenyl)tropane ({beta}-CIT) was performed to assess the improved specificity of IP-CIT over {beta}-CIT for the dopamine (DE) transporter, as shown previously by in vitro studies (n=10), ranging from 7 to 10 hours with 6.9 to 15 mCi injected dose, were completed in 3 baboons. Peripheral metabolism of the two ligands were similar The SPECT images utilized ROIs over striatum (which reflect DA transporters), midbrain (previously shown for {beta}-CIT to reflect primarily serotonin transporters), and the occipital lobe (a region of non-specific uptake). The time to peak specific striatal uptake (striatal minus occipital activity) was similar for IP-CIT and {beta}-CIT (377{plus_minus}60 and 410{plus_minus}60 min, respectively); whereas midbrain peak activity occurred at a significantly earlier time for IP-CIT (21{plus_minus}4 min) as compared to {beta}-CIT (60{plus_minus}17 min). At time of peak specific striatal activity, striatal to occipital ratios were 2.7+0.6 for IP-CIT and 7.6{plus_minus}0.7 for {beta}-CIT, and at time of peak midbrain activity, midbrain to occipital ratios were 1.1{plus_minus}0.1 for IP-CIT, and 1.7{plus_minus}0.2 for {beta}-CIT. At peak specific striatal time, normalized regional uptake values ({mu}Ci/cc per {mu}Ci injected dose per g body mass) for the striatum were 4.9{plus_minus}1.1 IP-CIT and 5.2{plus_minus}0.7 {beta}-CIT, whereas for the occipital lobe normalized regional uptake values were 1.9{plus_minus}0.4 IP-CIT and 0.7{plus_minus}0.2 for {beta}-CIT. Similar regional kinetics in the striatum were observed, as both ligands demonstrate comparable peak striatal uptake and time to peak.

  3. Filtering in SPECT Image Reconstruction

    PubMed Central

    Lyra, Maria; Ploussi, Agapi

    2011-01-01

    Single photon emission computed tomography (SPECT) imaging is widely implemented in nuclear medicine as its clinical role in the diagnosis and management of several diseases is, many times, very helpful (e.g., myocardium perfusion imaging). The quality of SPECT images are degraded by several factors such as noise because of the limited number of counts, attenuation, or scatter of photons. Image filtering is necessary to compensate these effects and, therefore, to improve image quality. The goal of filtering in tomographic images is to suppress statistical noise and simultaneously to preserve spatial resolution and contrast. The aim of this work is to describe the most widely used filters in SPECT applications and how these affect the image quality. The choice of the filter type, the cut-off frequency and the order is a major problem in clinical routine. In many clinical cases, information for specific parameters is not provided, and findings cannot be extrapolated to other similar SPECT imaging applications. A literature review for the determination of the mostly used filters in cardiac, brain, bone, liver, kidneys, and thyroid applications is also presented. As resulting from the overview, no filter is perfect, and the selection of the proper filters, most of the times, is done empirically. The standardization of image-processing results may limit the filter types for each SPECT examination to certain few filters and some of their parameters. Standardization, also, helps in reducing image processing time, as the filters and their parameters must be standardised before being put to clinical use. Commercial reconstruction software selections lead to comparable results interdepartmentally. The manufacturers normally supply default filters/parameters, but these may not be relevant in various clinical situations. After proper standardisation, it is possible to use many suitable filters or one optimal filter. PMID:21760768

  4. Differences in resting state regional cerebral blood flow assessed with 99mTc-HMPAO SPECT and brain atlas matching between depressed patients with and without tinnitus.

    PubMed

    Gardner, A; Pagani, M; Jacobsson, H; Lindberg, G; Larsson, S A; Wägner, A; Hällstrom, T

    2002-05-01

    An increased occurrence of major depressive disorder has been reported in tinnitus patients, and of tinnitus in depressive patients. Involvement of several Brodmann areas (BAs) has been reported in tinnitus perception. The aim of this study was to assess the regional cerebral blood flow (rCBF) changes in depressed patients with and without tinnitus. The rCBF distribution at rest was compared among 45 patients with a lifetime prevalence of major depressive disorder, of whom 27 had severe tinnitus, and 26 normal healthy subjects. 99mTc-hexamethylenepropylene amine oxime (99mTc-HMPAO) single photon emission computed tomography (SPECT), using a three-headed gamma camera, was performed and the uptake in 34 functional sub-volumes of the brain bilaterally was assessed by a computerized brain atlas. Decreased rCBF in right frontal lobe BA 45 (P<0.05), the left parietal lobe BA 39 (P<0.00) and the left visual association cortex BA 18 (P<0.05) was found in tinnitus patients compared with non-tinnitus patients. The proportion of tinnitus patients with pronounced rCBF alterations in one or more of the temporal lobe BAs 41+21+22 was increased compared to gender matched controls (P<0.00) and patients without tinnitus (P<0.05). Positive correlations were found between trait anxiety scales from the Karolinska Scales of Personality and rCBF in tinnitus patients only in three limbic BAs (P<0.01), and inverse correlations in non-tinnitus patients only in five BAs subserving auditory perception and processing (P<0.05). rCBF differences between healthy controls and depressed patients with and without tinnitus were found in this study. The rCBF alterations were distributed in the cortex and were particularly specific in the auditory cortex. These findings suggest that taking audiological symptoms into account may yield more consistent results between rCBF studies of depression.

  5. A new graphic method for estimation of distribution volume in chronic ischemic brain lesions on I-123 IMP SPECT; in prediction of regional CBF increase by bypass surgery

    SciTech Connect

    Odano, I.; Ohkubo, M.; Takahashi, N.

    1994-05-01

    The estimate the distribution volume (Vd) of Iodine-123 IMP brain SPECT, we developed a new graphic plot, the rate constant square method, which was useful to predict an increase of rCBF in the ischemic lesions caused by bypass surgery. The tracer kinetics of IMP was assumed to be a 2-compartment model as follows: dCb(t)/dt=K1Ca(t)-k2Cb(t), where K1 is rCBF(ml/g/min), k2 is the washout constant(/min), and K1/k2 is defined as distribution volume (Vd:ml/g). When input function Ca(t) is prepared, we can determine the relationship between K1, Delayed/Early ratio and Vd on the graph. The method was applied to 13 patients with chronic cerebral infarction. Regional CBF was measured by the microsphere model and early and delayed scans were performed. In the normal area, K1 and Delayed/Early ratio were 0.5 ml/g/min and 1.0, respectively, then Vd (=31.5 ml/g) was obtained on the graph. 30.0 ml/g, the value in the infarct area was reduced. After bypass surgery undertaken on five patients, we observed a significant relationship between % increase of rCBF in the lesions and values of Vd. Since Vd reflects the extent of IMP retention in the brain tissue, we can predict an increase of rCBF by the bypass operation using this method.

  6. Single photon emission computed tomography (SPECT) in epilepsy

    SciTech Connect

    Leroy, R.F.

    1991-12-31

    Epilepsy is a common neurologic disorder which has just begun to be studied with single photon emission computerized tomography (SPECT). Epilepsy usually is studied with electroencephalographic (EEG) techniques that demonstrate the physiologic changes that occur during seizures, and with neuroimaging techniques that show the brain structures where seizures originate. Neither method alone has been adequate to describe the pathophysiology of the patient with epilepsy. EEG techniques lack anatomic sensitivity, and there are no structural abnormalities shown by neuroimaging which are specific for epilepsy. Functional imaging (FI) has developed as a physiologic tool with anatomic sensitivity, and SPECT has been promoted as a FI technique because of its potentially wide availability. However, SPECT is early in its development and its clinical utility for epilepsy still has to be demonstrated. To understand this role of SPECT, consideration must be given to the pathophysiology of epilepsy, brain physiology, types of seizure, epileptic syndromes, and the SPECT technique itself. 44 refs., 2 tabs.

  7. Cerebral SPECT imaging: Impact on clinical management

    SciTech Connect

    Bloom, M.; Jacobs, S.; Pozniakof, T.

    1994-05-01

    Although cerebral SPECT has been reported to be of value in a variety of neurologic disorders, there is limited data available on the value of SPECT relative to clinical management decisions. The purpose of this study was to determine the effect of cerebral SPECT imaging on patient management. A total of 94 consecutive patients referred for clinical evaluation with brain SPECT were included in this study. Patients were assigned to one of nine groups depending on the clinical indication for the study. These groups included transient ischemia (16), stroke (20), dementia (18), seizures (5), hemorrhage (13), head trauma (6), arteriovenous malformations (6), encephalopathy (6) and a miscellaneous (4) group. All patients were injected with 99mTc HMPAO in doses ranging from 15 mCi to 22 mCi (555 MBq to 814 MBq) and scanned on a triple headed SPECT gamma camera. Two weeks after completion of the study, a standardized interview was conducted between the nuclear and referring physicians to determine if the SPECT findings contributed to an alteration in patient management. Overall, patient management was significantly altered in 47% of the cases referred. The greatest impact on patient management occurred in the group evaluated for transient ischemia, where a total of 13/16 (81%) of patients had their clinical management altered as a result of the cerebral SPECT findings. Clinical management was altered in 61% of patients referred for evaluation of dementia, 67% of patients evaluated for arteriovenous malformations, and 50% of patients with head trauma. In the remainder of the patients, alteration in clinical management ranged from 17% to 50% of patients. This study demonstrates the clinical utility of cerebral SPECT imaging since in a significant number of cases clinical management was altered as a result of the examination. Long term follow up will be necessary to determine patient outcome.

  8. Technological Development and Advances in SPECT/CT

    PubMed Central

    Seo, Youngho; Aparici, Carina Mari; Hasegawa, Bruce H

    2010-01-01

    SPECT/CT has emerged over the past decade as a means of correlating anatomical information from CT with functional information from SPECT. The integration of SPECT and CT in a single imaging device facilitates anatomical localization of the radiopharmaceutical to differentiate physiological uptake from that associated with disease and patient-specific attenuation correction to improve the visual quality and quantitative accuracy of the SPECT image. The first clinically available SPECT/CT systems performed emission-transmission imaging using a dual-headed SPECT camera and a low-power x-ray CT sub-system. Newer SPECT/CT systems are available with high-power CT sub-systems suitable for detailed anatomical diagnosis, including CT coronary angiography and coronary calcification that can be correlated with myocardial perfusion measurements. The high-performance CT capabilities also offer the potential to improve compensation of partial volume errors for more accurate quantitation of radionuclide measurement of myocardial blood flow and other physiological processes and for radiation dosimetry for radionuclide therapy. In addition, new SPECT technologies are being developed that significantly improve the detection efficiency and spatial resolution for radionuclide imaging of small organs including the heart, brain, and breast, and therefore may provide new capabilities for SPECT/CT imaging in these important clinical applications. PMID:18396178

  9. Importance of 123I-ioflupane SPECT and Myocardial MIBG Scintigraphy to Determine the Candidate of Deep Brain Stimulation for Parkinson’s Disease

    PubMed Central

    ASAHI, Takashi; KASHIWAZAKI, Daina; YONEYAMA, Tatsuya; NOGUCHI, Kyo; KURODA, Satoshi

    2016-01-01

    123I-ioflupane SPECT (DaTscan) is an examination that detects presynaptic dopamine neuronal dysfunction, and has been used as a diagnostic tool to identify degenerative parkinsonism. Additionally, myocardial 123I-metaiodobenzyl guanidine (MIBG) scintigraphy measures the concentration of cardiac sympathetic nerve fibers and is used to diagnose Parkinson’s disease (PD). These exams are used as adjuncts in the diagnosis of parkinsonism, however, the relationship of these two examinations are not well-known. We investigated the relationship of these two scanning results specifically for determining the use of deep brain stimulation therapy (DBS). Subjects were Japanese patients with suspected striatonigral degeneration, including PD; DaTscans and myocardial MIBG scintigraphy were performed. The mean values of the left-right specific binding ratios (SBRs) from the DaTscan, and the early/delayed heart-to-mediastinum ratios (HMRs) from the MIBG scintigraphy were calculated. Using simple linear regression analysis, we compared the SBR and early/delayed HMR values. Twenty-four patients were enrolled in this study. Twenty-one patients were positive via the DaTscan, and the MIBG scintigraphy results showed 14 patients were positive. SBR and both early and delayed HMR were positively correlated in cases of PD, but negative in non-PD cases. A mean SBR value less than 3.0 and a delayed HMR value less than 1.7 indicated a Hoehn-Yahr stage 3 or 4 for PD, which is commonly regarded as a level appropriate for initiating DBS therapy. Our results indicate that performing both DaTscan and MIBG scintigraphy is useful for the evaluation of surgical intervention in PD. PMID:26794041

  10. Simultaneous Tc-99m and I-123 dual-radionuclide imaging with a solid-state detector-based brain-SPECT system and energy-based scatter correction.

    PubMed

    Takeuchi, Wataru; Suzuki, Atsuro; Shiga, Tohru; Kubo, Naoki; Morimoto, Yuichi; Ueno, Yuichiro; Kobashi, Keiji; Umegaki, Kikuo; Tamaki, Nagara

    2016-12-01

    A brain single-photon emission computed tomography (SPECT) system using cadmium telluride (CdTe) solid-state detectors was previously developed. This CdTe-SPECT system is suitable for simultaneous dual-radionuclide imaging due to its fine energy resolution (6.6 %). However, the problems of down-scatter and low-energy tail due to the spectral characteristics of a pixelated solid-state detector should be addressed. The objective of this work was to develop a system for simultaneous Tc-99m and I-123 brain studies and evaluate its accuracy. A scatter correction method using five energy windows (FiveEWs) was developed. The windows are Tc-lower, Tc-main, shared sub-window of Tc-upper and I-lower, I-main, and I-upper. This FiveEW method uses pre-measured responses for primary gamma rays from each radionuclide to compensate for the overestimation of scatter by the triple-energy window method that is used. Two phantom experiments and a healthy volunteer experiment were conducted using the CdTe-SPECT system. A cylindrical phantom and a six-compartment phantom with five different mixtures of Tc-99m and I-123 and a cold one were scanned. The quantitative accuracy was evaluated using 18 regions of interest for each phantom. In the volunteer study, five healthy volunteers were injected with Tc-99m human serum albumin diethylene triamine pentaacetic acid (HSA-D) and scanned (single acquisition). They were then injected with I-123 N-isopropyl-4-iodoamphetamine hydrochloride (IMP) and scanned again (dual acquisition). The counts of the Tc-99m images for the single and dual acquisitions were compared. In the cylindrical phantom experiments, the percentage difference (PD) between the single and dual acquisitions was 5.7 ± 4.0 % (mean ± standard deviation). In the six-compartment phantom experiment, the PDs between measured and injected activity for Tc-99m and I-123 were 14.4 ± 11.0 and 2.3 ± 1.8 %, respectively. In the volunteer study, the PD between the single

  11. Technetium-99m bis (aminoethanethiol) complexes with amine sidechains--potential brain perfusion imaging agents for SPECT

    SciTech Connect

    Efange, S.M.; Kung, H.F.; Billings, J.; Guo, Y.Z.; Blau, M.

    1987-06-01

    In an effort to develop new clinically useful technetium-99m bis(aminoethanethiol) ((/sup 99m/Tc)BAT) complexes for the evaluation of regional cerebral perfusion, two new BAT ligands containing amines in the sidechain were synthesized and subsequently complexed with /sup 99m/Tc to yield the target complexes: (/sup 99m/Tc)DEA and (/sup 99m/Tc)TMPDA. Each complex was obtained as mixtures of two isomers, syn and anti, which were separated chromatographically. In biodistribution studies, both isomers of (/sup 99m/Tc)TMPDA showed little uptake in the brain. In contrast, the brain uptake values at 2 and 15 min for (/sup 99m/Tc)DEA-anti were 0.99 and 0.26, whereas, the corresponding values for DEA-syn were 2.27, 0.64% dose/organ, respectively. Autoradiographic studies (in rats) using both isomers of (/sup 99m/Tc)DEA show a fixed regional distribution and a higher concentration of radioactivity in the gray matter relative to the white matter. Planar imaging using (/sup 99m/Tc)DEA-syn clearly demonstrates localization of the complex in the brain with a T 1/2 of 41 min, suggesting some potential for use with single photon emission computed tomography.

  12. Recent advances in SPECT

    SciTech Connect

    Tsui, Benjamin M. W.

    1998-08-28

    Single photon emission computed tomography (SPECT) is a medical imaging modality that combines conventional nuclear medicine imaging technique and methods of computed tomography (CT). From images that represent the biodistribution of the injected radiopharmaceutical in the patient, SPECT provides functional information that is unique. The first SPECT system was developed in the sixties. However, early progress of SPECT was hampered by the lack of adequate image reconstruction methods. The development of x-ray CT and image reconstruction methods in the seventies spurred a renewed interest in SPECT. In 1981, the first commercial SPECT system based on a single rotating camera was available for clinical use. Today, most modern SPECT systems consist of multiple cameras that rotate around the patients. They have better spatial resolution and higher detection efficiency as compared to the earlier single camera systems. Recently, a new generation of dual camera systems allowing for coincidence imaging of positron emitting radiopharmaceuticals has emerged in the commercial market. Additionally, new quantitative image reconstruction methods are under development. They compensate for image degrading factors including attenuation, collimator-detector blurring and scatter. Also, they result in SPECT images with improved image quality and more accurately represent the three-dimensional radioactivity distribution in the patient. Such advances in radiopharmaceuticals, instrumentation, image reconstruction, compensation methods, and clinical applications have fueled a steady growth of SPECT as an important diagnostic tool in patient management.

  13. [Usefulness of brain SPECT with HMPAO-99mTc and psychological tests for diagnosis of neurological involvement in Behçet's disease].

    PubMed

    García Hernández, Francisco José; Ocaña Medina, Celia; Mateos Romero, Luis; Sánchez Román, Julio; García Solís, David; Franco-Baux, Joaquín Ruiz; Mora Roche, Joaquín; Mora Merchán, Joaquín

    2002-10-12

    The purpose of this study was to establish the usefulness of single photon emission computed tomography (SPECT) and psychological tests for diagnostic of neuro-Behçet (NB) and to evaluate the clinical significance of neurological symptoms that are difficult to interpret and asymptomatic abnormalities in diagnostic tests. Forty patients with Behçet's disease (BD) were enrrolled for being studied with magnetic resonance imaging (MRI), SPECT and psychological tests. MRI findings were abnormal in 52,9% of patients with neurological involvement and 23.1% without it (p < 0.1), whereas SPECT findings were abnormal in 82.3% and 61.5%, respectively (no significant difference). The difference between MRI and SPECT findings was significant (p < 0.02 for the complete group; p < 0.05 for patients without neurological symptoms; p < 0.08 for patients with them). The mean follow-up period was 42.6 months, and no patient without neurological involvement or those only with neurological symptoms that are difficult to interprete developed definite neurological involvement. The results of cognitive tests were not significantly different among patients with or without neurological involvement, neither among patients and controls. The scale 2 (depression) of the personality test was more frequent in patients with definite neurological involvement (p < 0.05). SPECT seems more sensible and less specific than MRI for diagnostic of NB. Although SPECT findings were frequently abnormal in patients with BD without neurological involvement or with neurological symptoms hard to interpret, no patient from this group developed a NB flare after a long follow-up period. A characteristic personality was found for patients with BD.

  14. SPECT radiopharmaceuticals for dementia.

    PubMed

    Guidotti, Claudio; Farioli, Daniela; Gaeta, Maria Chiara; Giovannini, Elisabetta; Lazzeri, Patrizia; Meniconi, Martina; Ciarmiello, Andrea

    2013-12-01

    Over the last decade the interest towards functional neuroimaging has gradually increased, especially in the field of neurodegenerative diseases. At present, diagnosis of dementia is mostly clinical. Numerous modalities of neuroimaging are today available, each of them allowing a different aspect of neurodegeneration to be investigated. Although during the last period many have predicted a forthcoming disappearance of SPECT imaging in favour of the PET imaging, many new radiotracers SPECT, dual-SPECT tracers techniques and receptor targeting designed radiopharmaceuticals are currently at study. Besides, last decade has also assisted to the development of new SPECT imaging systems, most of them integrated with other imaging modalities (MRI, CT, ultrasound techniques), granting improved imaging capabilities. All these improved conditions, especially appealing for the neuroimaging, together with the new radiopharmaceuticals in development may renovate the interest for SPECT clinical applications.

  15. Radiosynthesis, In Vivo Biological Evaluation, and Imaging of Brain Lesions with [123I]-CLINME, a New SPECT Tracer for the Translocator Protein

    PubMed Central

    Mattner, F.; Quinlivan, M.; Greguric, I.; Pham, T.; Liu, X.; Jackson, T.; Berghofer, P.; Fookes, C. J. R.; Dikic, B.; Gregoire, M.-C.; Dolle, F.; Katsifis, A.

    2015-01-01

    The high affinity translocator protein (TSPO) ligand 6-chloro-2-(4′-iodophenyl)-3-(N,N-methylethyl)imidazo[1,2-a]pyridine-3-acetamide (CLINME) was radiolabelled with iodine-123 and assessed for its sensitivity for the TSPO in rodents. Moreover neuroinflammatory changes on a unilateral excitotoxic lesion rat model were detected using SPECT imaging. [123I]-CLINME was prepared in 70–80% radiochemical yield. The uptake of [123I]-CLINME was evaluated in rats by biodistribution, competition, and metabolite studies. The unilateral excitotoxic lesion was performed by injection of α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid unilaterally into the striatum. The striatum lesion was confirmed and correlated with TSPO expression in astrocytes and activated microglia by immunohistochemistry and autoradiography. In vivo studies with [123I]-CLINME indicated a biodistribution pattern consistent with TPSO distribution and the competition studies with PK11195 and Ro 5-4864 showed that [123I]-CLINME is selective for this site. The metabolite study showed that the extractable radioactivity was unchanged [123I]-CLINME in organs which expresses TSPO. SPECT/CT imaging on the unilateral excitotoxic lesion indicated that the mean ratio uptake in striatum (lesion : nonlesion) was 2.2. Moreover, TSPO changes observed by SPECT imaging were confirmed by immunofluorescence, immunochemistry, and autoradiography. These results indicated that [123I]-CLINME is a promising candidate for the quantification and visualization of TPSO expression in activated astroglia using SPECT. PMID:26199457

  16. Abdominal SPECT imaging

    SciTech Connect

    Van Heertum, R.L.; Brunetti, J.C.; Yudd, A.P.

    1987-07-01

    Over the past several years, abdominal single photon emission computed tomography (SPECT) imaging has evolved from a research tool to an important clinical imaging modality that is helpful in the diagnostic assessment of a wide variety of disorders involving the abdominal viscera. Although liver-spleen imaging is the most popular of the abdominal SPECT procedures, blood pool imaging is becoming much more widely utilized for the evaluation of cavernous hemangiomas of the liver as well as other vascular abnormalities in the abdomen. Adjunctive indium leukocyte and gallium SPECT studies are also proving to be of value in the assessment of a variety of infectious and neoplastic diseases. As more experience is acquired in this area, SPECT should become the primary imaging modality for both gallium and indium white blood cells in many institutions. Renal SPECT, on the other hand, has only recently been used as a clinical imaging modality for the assessment of such parameters as renal depth and volume. The exact role of renal SPECT as a clinical tool is, therefore, yet to be determined. 79 references.

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

    SciTech Connect

    Not Available

    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)

  18. The role of cognitive group therapy and happiness training on cerebral blood flow using 99mTc-ECD brain perfusion SPECT: a quasi-experimental study of depressed patients.

    PubMed

    Azizi, M; Bahrieniain, S A; Baghdasarians, A; Emamipur, S; Azizmohammadi, Z; Qutbi, S M; Javadi, H; Assadi, M; Asli, I N

    2014-01-01

    The purpose of this study is to investigate the impact of cognitive group therapy and happiness training objectively in the local cerebral blood flow of patients with major depression (MD). The present research is semi-experimental to pre- and post-test with a control group. Three groups were formed, and this number was incorporated in each group: 12 patients were chosen randomly; the first group of depressed patients benefited from the combination of pharmacotherapy and sessions of cognitive group therapy; the second group used a combination of pharmacotherapy and sessions of happiness training; and a third group used only pharmacotherapy. We compared cognitive-behavioural therapy and happiness training efficacy with only pharmacotherapy in MD patients. We performed brain perfusion SPECT in each group, before and after each trial. The study was conducted on 36 patients with MD (32 women and 4 men; mean age: 41.22 ± 9.08; range: 27-65 years). There were significant differences regarding the two trial effects into two experimental groups (p < 0/001) before and after trials, while such differences were not significant in the control group (p > 0.05). In addition, there was significant difference among the regional cerebral blood flow in the frontal and prefrontal regions into two experimental groups before and after trials (p < 0/001), while such differences were not significant in the control group (p > 0.05). This study demonstrated decreased cerebral perfusion in the frontal regions in MD patients, which increased following cognitive group therapy and happiness training. Because of its availability, low costs, easy performance, and the objective semi-quantitative information supplied, brain perfusion SPECT scanning might be useful to assess the diagnosis and therapy efficacy. Further exploration is needed to validate its clinical role.

  19. PET and SPECT imaging in veterinary medicine.

    PubMed

    LeBlanc, Amy K; Peremans, Kathelijne

    2014-01-01

    Veterinarians have gained increasing access to positron emission tomography (PET and PET/CT) imaging facilities, allowing them to use this powerful molecular imaging technique for clinical and research applications. SPECT is currently being used more in Europe than in the United States and has been shown to be useful in veterinary oncology and in the evaluation of orthopedic diseases. SPECT brain perfusion and receptor imaging is used to investigate behavioral disorders in animals that have interesting similarities to human psychiatric disorders. This article provides an overview of the potential applications of PET and SPECT. The use of commercially available and investigational PET radiopharmaceuticals in the management of veterinary disease has been discussed. To date, most of the work in this field has utilized the commercially available PET tracer, (18)F-fluorodeoxyglucose for oncologic imaging. Normal biodistribution studies in several companion animal species (cats, dogs, and birds) have been published to assist in lesion detection and interpretation for veterinary radiologists and clinicians. Studies evaluating other (18)F-labeled tracers for research applications are underway at several institutions and companion animal models of human diseases are being increasingly recognized for their value in biomarker and therapy development. Although PET and SPECT technologies are in their infancy for clinical veterinary medicine, increasing access to and interest in these applications and other molecular imaging techniques has led to a greater knowledge and collective body of expertise for veterinarians worldwide. Initiation and fostering of physician-veterinarian collaborations are key components to the forward movement of this field.

  20. Quantitative myocardial perfusion SPECT.

    PubMed

    Tsui, B M; Frey, E C; LaCroix, K J; Lalush, D S; McCartney, W H; King, M A; Gullberg, G T

    1998-01-01

    In recent years, there has been much interest in the clinical application of attenuation compensation to myocardial perfusion single photon emission computed tomography (SPECT) with the promise that accurate quantitative images can be obtained to improve clinical diagnoses. The different attenuation compensation methods that are available create confusion and some misconceptions. Also, attenuation-compensated images reveal other image-degrading effects including collimator-detector blurring and scatter that are not apparent in uncompensated images. This article presents basic concepts of the major factors that degrade the quality and quantitative accuracy of myocardial perfusion SPECT images, and includes a discussion of the various image reconstruction and compensation methods and misconceptions and pitfalls in implementation. The differences between the various compensation methods and their performance are demonstrated. Particular emphasis is directed to an approach that promises to provide quantitative myocardial perfusion SPECT images by accurately compensating for the 3-dimensional (3-D) attenuation, collimator-detector response, and scatter effects. With advances in the computer hardware and optimized implementation techniques, quantitatively accurate and high-quality myocardial perfusion SPECT images can be obtained in clinically acceptable processing time. Examples from simulation, phantom, and patient studies are used to demonstrate the various aspects of the investigation. We conclude that quantitative myocardial perfusion SPECT, which holds great promise to improve clinical diagnosis, is an achievable goal in the near future.

  1. Quantification of rat brain SPECT with 123I-ioflupane: evaluation of different reconstruction methods and image degradation compensations using Monte Carlo simulation

    NASA Astrophysics Data System (ADS)

    Roé-Vellvé, N.; Pino, F.; Falcon, C.; Cot, A.; Gispert, J. D.; Marin, C.; Pavía, J.; Ros, D.

    2014-08-01

    SPECT studies with 123I-ioflupane facilitate the diagnosis of Parkinson’s disease (PD). The effect on quantification of image degradations has been extensively evaluated in human studies but their impact on studies of experimental PD models is still unclear. The aim of this work was to assess the effect of compensating for the degrading phenomena on the quantification of small animal SPECT studies using 123I-ioflupane. This assessment enabled us to evaluate the feasibility of quantitatively detecting small pathological changes using different reconstruction methods and levels of compensation for the image degrading phenomena. Monte Carlo simulated studies of a rat phantom were reconstructed and quantified. Compensations for point spread function (PSF), scattering, attenuation and partial volume effect were progressively included in the quantification protocol. A linear relationship was found between calculated and simulated specific uptake ratio (SUR) in all cases. In order to significantly distinguish disease stages, noise-reduction during the reconstruction process was the most relevant factor, followed by PSF compensation. The smallest detectable SUR interval was determined by biological variability rather than by image degradations or coregistration errors. The quantification methods that gave the best results allowed us to distinguish PD stages with SUR values that are as close as 0.5 using groups of six rats to represent each stage.

  2. Design and simulation of a high-resolution stationary SPECT system for small animals

    NASA Astrophysics Data System (ADS)

    Beekman, Freek J.; Vastenhouw, Brendan

    2004-10-01

    Exciting new SPECT systems can be created by combining pinhole imaging with compact high-resolution gamma cameras. These new systems are able to solve the problem of the limited sensitivity-resolution trade-off that hampers contemporary small animal SPECT. The design presented here (U-SPECT-III) uses a set of detectors placed in a polygonal configuration and a cylindrical collimator that contains 135 pinholes arranged in nine rings. Each ring contains 15 gold pinhole apertures that focus on the centre of the cylinder. A non-overlapping projection is acquired via each pinhole. Consequently, when a mouse brain is placed in the central field-of-view, each voxel in the cerebrum can be observed via 130 to 135 different pinholes simultaneously. A method for high-resolution scintillation detection is described that eliminates the depth-of-interaction problem encountered with pinhole cameras, and is expected to provide intrinsic detector resolutions better than 150 µm. By means of simulations U-SPECT-III is compared to a simulated dual pinhole SPECT (DP-SPECT) system with a pixelated array consisting of 2.0 × 2.0 mm NaI crystals. Analytic calculations indicate that the proposed U-SPECT-III system yields an almost four times higher linear and about sixty times higher volumetric system resolution than DP-SPECT, when the systems are compared at matching system sensitivity. In addition, it should be possible to achieve a 15 up to 30 times higher sensitivity with U-SPECT-III when the systems are compared at equal resolution. Simulated images of a digital mouse-brain phantom show much more detail with U-SPECT-III than with DP-SPECT. In a resolution phantom, 0.3 mm diameter cold rods are clearly visible with U-SPECT-III, whereas with DP-SPECT the smallest visible rods are about 0.6-0.8 mm. Furthermore, with U-SPECT-III, the image deformations outside the central plane of reconstruction that hamper conventional pinhole SPECT are strongly suppressed. Simulation results indicate

  3. A SPECT study in internal carotid artery occlusion: Discrepancies between flow image and neurologic deficits

    SciTech Connect

    Moriwaki, H.; Hougaku, H.; Matsuda, I.; Kusunoki, M.; Shirai, J. )

    1989-08-01

    A SPECT (single photon emission computed tomography) study in internal carotid artery (ICA) occlusion was performed in 6 patients. The validity of iodoamphetamine (IMP) SPECT study in the evaluation of cerebral blood flow (CBF) or neurologic function is still controversial. In this study, the authors showed several cases in whom SPECT images of brain were not compatible with their neurologic deficits. In 2 typical cases, a large low-density area was observed in the non-dominant hemisphere in computed tomography (CT) scan, but no apparent motor-sensory deficits in left limbs were present. In these patients, SPECT study also revealed flow reduction in the affected side of the brain. So there was a possibility that an IMP brain image could not always reflect CBF, which maintains neurologic function of the brain.

  4. Single Photon Emission Computed Tomography (SPECT) Experience with (S)-5-[123I]iodo-3-(2-azetidinylmethoxy)pyridine (5-[123I]IA) in the Living Human Brain of Smokers and Nonsmokers

    PubMed Central

    BRAŠIĆ, JAMES ROBERT; ZHOU, YUN; MUSACHIO, JOHN L.; HILTON, JOHN; FAN, HONG; CRABB, ANDREW; ENDRES, CHRISTOPHER J.; REINHARDT, MELVIN J.; DOGAN, AHMET S.; ALEXANDER, MOHAB; ROUSSET, OLIVIER; MARIS, MARIKA A.; GALECKI, JEFFREY; NANDI, AYON; WONG, DEAN F.

    2009-01-01

    (S)-5-[123I]iodo-3-(2-azetidinylmethoxy)pyridine (5-[123I]IA), a novel potent radioligand for high-affinity α4β2* neuronal nicotinic acetylcholine receptors (nAChRs), provides a means to evaluate the density and the distribution of nAChRs in the living human brain. We sought in healthy adult smokers and nonsmokers to (1) evaluate the safety, tolerability, and efficacy of 5-[123I]IA in an open nonblind trial and (2) to estimate the density and distribution of α4β2* nAChRs in the brain. Single photon emission computed tomography (SPECT) was performed for five hours after the intravenous administration of approximately 0.001 μg/kg (approximately 10 mCi) 5-[123I]IA. Blood pressure, heart rate, and neurobehavioral status were monitored before, during, and after the administration of 5-[123I]IA to twelve healthy adults (8 men and 4 women) (6 smokers and 6 nonsmokers) ranging in age from 19 to 46 years (mean = 28.25, standard deviation = 8.20). High plasma nicotine level was significantly associated with low 5-[123I]IA binding in (1) the caudate head, the cerebellum, the cortex, and the putamen, utilizing both the Sign and Mann-Whitney U tests, (2) the fusiform gyrus, the hippocampus, the parahippocampus, and the pons utilizing the Mann-Whitney U test, and (3)the thalamus utilizing the Sign test. We conclude that 5-[123I]IA is a safe, well-tolerated, and effective pharmacologic agent for human subjects to estimate high-affinity α4/β2 nAChRs in the living human brain. PMID:19140167

  5. Cerebral blood flow imaging with thallium-201 diethyldithiocarbamate SPECT

    SciTech Connect

    van Royen, E.A.; de Brune, J.F.H.; Hill, T.C.; Vyth, A.; Limburg, M.; Byse, B.L.; O'Leary, D.H.; de Jong, J.M.; Hijdra, A.; van der Schoot, J.B.

    1987-02-01

    Thallium-201 diethyldithiocarbamate ((/sup 201/TI)DDC) was studied in humans as an agent for cerebral blood flow imaging. Brain uptake proved to be complete 90 sec after injection with no appreciable washout or redistribution for hours. Intracarotid injection suggested an almost 100% extraction during the first passage. Whole-body distribution studies demonstrated a brain uptake of 4.3% of the dose compared with 0.9% for (/sup 201/TI)chloride. No differences were found in the distribution of (/sup 201/TI)DDC versus (/sup 201/TI)chloride in other organs. After the injection of 3 mCi /sup 201/TI, good quality single photon emission computed tomographic (SPECT) images of the brain were obtained with both a rotating gamma camera and a multidetector system. In ischemic brain disease, perfusion defects were easily demonstrated. We conclude that (/sup 201/TI)DDC is a suitable radiopharmaceutical for SPECT studies of cerebral blood flow.

  6. Molecular SPECT Imaging: An Overview

    PubMed Central

    Khalil, Magdy M.; Tremoleda, Jordi L.; Bayomy, Tamer B.; Gsell, Willy

    2011-01-01

    Molecular imaging has witnessed a tremendous change over the last decade. Growing interest and emphasis are placed on this specialized technology represented by developing new scanners, pharmaceutical drugs, diagnostic agents, new therapeutic regimens, and ultimately, significant improvement of patient health care. Single photon emission computed tomography (SPECT) and positron emission tomography (PET) have their signature on paving the way to molecular diagnostics and personalized medicine. The former will be the topic of the current paper where the authors address the current position of the molecular SPECT imaging among other imaging techniques, describing strengths and weaknesses, differences between SPECT and PET, and focusing on different SPECT designs and detection systems. Radiopharmaceutical compounds of clinical as well-preclinical interest have also been reviewed. Moreover, the last section covers several application, of μSPECT imaging in many areas of disease detection and diagnosis. PMID:21603240

  7. [Normal database (NDB) of 123I-IMP brain perfusion SPECT examination is affected by statistical image analysis in the presence or absence of scatter correction and attenuation correction].

    PubMed

    Shimada, Hirotaka; Otake, Hidenori; Higuchi, Tetsuya; Arisaka, Yukiko; Oriuchi, Noboru; Endo, Keigo

    2012-11-01

    The purpose of our study is the establishment of normal database (NDB) from persons (aged 50-80 years) for 3D-SSP analysis of 123I-IMP brain perfusion SPECT image, and we analyzed whether the presence or absence of image correction methods, scatter correction (SC) and attenuation correction (AC), affects the created NDB and 3D-SSP analysis. We created NDB from 63 healthy volunteers (32 males and 31 females, aged 50-80 years), and calculated the coefficient of variation for each pixel from the mean value and standard deviation. Next, we compared the visual assessments of the standard deviation images by each image correction method, and the coefficient of variation of SEE analysis in each part of the brain. Furthermore, we examined frontotemporal dementia and healthy volunteers by 3D-SSP analysis, and evaluated the differences of Z-score in the presence or absence of image correction methods. In NDB, the coefficient of variation was the minimum when SC and AC were not applied and the maximum in periventricular and cerebellum when SC and AC were applied. In Z-score image of 3D-SSP analysis, Z-score of the low value was the maximum when SC and AC were not applied. It was shown that the results from NDB coefficient of variation and 3D-SSP analysis were affected by the differences of image correction methods. It is important to understand the feature of imaging reconstruction conditions in your own facilities, and evaluate 3D-SSP analysis.

  8. Molecular Imaging of Conscious, Unrestrained Mice with AwakeSPECT

    SciTech Connect

    Baba, Justin S.; Endres, Christopher J.; Foss, Catherine A.; Nimmagadda, Sridhar; Jung, Hyeyun; Goddard, James S.; Lee, Seung Joon; McKisson, John; Smith, Mark F.; Stolin, Alexander V.; Weisenberger, Andrew G.; Pomper, Martin G.

    2013-06-01

    We have developed a SPECT imaging system, AwakeSPECT, to enable molecular brain imaging of untrained mice that are conscious, unanesthetized, and unrestrained. We accomplished this with head tracking and motion correction techniques. Methods: The capability of the system for motion-corrected imaging was demonstrated with a ^99mTc-pertechnetate phantom, ^99mTc-methylene diphosphonate bone imaging, and measurement of the binding potential of the dopamine transporter radioligand ^123I-ioflupane in mouse brain in the awake and anesthetized (isoflurane) states. Stress induced by imaging in the awake state was assessed through measurement of plasma corticosterone levels. Results: AwakeSPECT provided high-resolution bone images reminiscent of those obtained from CT. The binding potential of ^123I-ioflupane in the awake state was on the order of 50% of that obtained with the animal under anesthesia, consistent with previous studies in nonhuman primates. Levels of stress induced were on the order of those seen in other behavioral tasks and imaging studies of awake animals. Conclusion: These results demonstrate the feasibility of SPECT molecular brain imaging of mice in the conscious, unrestrained state and demonstrate the effects of isoflurane anesthesia on radiotracer uptake.

  9. Molecular Imaging of Conscious, Unrestrained Mice with AwakeSPECT

    SciTech Connect

    Baba, Justin S; Endres, Christopher; Foss, Catherine; Nimmagadda, Sridhar; Jung, Hyeyun; Goddard Jr, James Samuel; Lee, Seung Joon; McKisson, John; Smith, Mark F.; Stolin, Alexander; Weisenberger, Andrew G.; Pomper, Martin

    2013-01-01

    We have developed a SPECT imaging system, AwakeSPECT, to enable molecular brain imaging of untrained mice that are conscious, unanesthetized, and unrestrained. We accomplished this with head tracking and motion correction techniques. Methods: The capability of the system for motion-corrected imaging was demonstrated with a 99mTc-pertechnetate phantom, 99mTcmethylene diphosphonate bone imaging, and measurement of the binding potential of the dopamine transporter radioligand 123I-ioflupane in mouse brain in the awake and anesthetized (isoflurane) states. Stress induced by imaging in the awake state was assessed through measurement of plasma corticosterone levels. Results: AwakeSPECT provided high-resolution bone images reminiscent of those obtained from CT. The binding potential of 123I-ioflupane in the awake state was on the order of 50% of that obtained with the animal under anesthesia, consistent with previous studies in nonhuman primates. Levels of stress induced were on the order of those seen in other behavioral tasks and imaging studies of awake animals. Conclusion: These results demonstrate the feasibility of SPECT molecular brain imaging of mice in the conscious, unrestrained state and demonstrate the effects of isoflurane anesthesia on radiotracer uptake.

  10. Parallel-hole collimator concept for stationary SPECT imaging.

    PubMed

    Pato, Lara R V; Vandenberghe, Stefaan; Zedda, Tiziana; Van Holen, Roel

    2015-11-21

    Parallel-hole SPECT collimators have traditionally been manufactured by stacking sheets of lead foil or by casting. These techniques significantly restrict our options in terms of collimator geometry. However, recent developments in metal additive manufacturing are making novel collimator designs possible, giving rise to new opportunities in SPECT imaging. In this paper we propose an innovative type of collimator for stationary SPECT, using parallel-holes whose collimation direction depends on their axial position. Its main advantage compared to current stationary SPECT systems (which are based on pinholes) is that, using only axial bed translations, we can achieve complete angular sampling of an increased portion of the transaxial area of the collimator bore. This allows the system to be much more compact than current stationary SPECT systems that image objects of the same size. We describe three possible designs, for full-body, brain and small-animal imaging, respectively, and test their feasibility using simulations. The system modeling method is validated against realistic Monte Carlo simulations, and then used in the evaluation of the systems' performances and reconstructions. The simulations show that the system is able to reconstruct objects occupying the predicted field of view ([Formula: see text] of the transaxial area of the bore) without sampling artifacts. In particular, we perform reconstructions from noisy projection data obtained for an activity and scanning time similar to standard protocols for the three applications, and the resulting images indicate the possibility of using the proposed systems in practice.

  11. Parallel-hole collimator concept for stationary SPECT imaging

    NASA Astrophysics Data System (ADS)

    Pato, Lara R. V.; Vandenberghe, Stefaan; Zedda, Tiziana; Van Holen, Roel

    2015-11-01

    Parallel-hole SPECT collimators have traditionally been manufactured by stacking sheets of lead foil or by casting. These techniques significantly restrict our options in terms of collimator geometry. However, recent developments in metal additive manufacturing are making novel collimator designs possible, giving rise to new opportunities in SPECT imaging. In this paper we propose an innovative type of collimator for stationary SPECT, using parallel-holes whose collimation direction depends on their axial position. Its main advantage compared to current stationary SPECT systems (which are based on pinholes) is that, using only axial bed translations, we can achieve complete angular sampling of an increased portion of the transaxial area of the collimator bore. This allows the system to be much more compact than current stationary SPECT systems that image objects of the same size. We describe three possible designs, for full-body, brain and small-animal imaging, respectively, and test their feasibility using simulations. The system modeling method is validated against realistic Monte Carlo simulations, and then used in the evaluation of the systems’ performances and reconstructions. The simulations show that the system is able to reconstruct objects occupying the predicted field of view (75% of the transaxial area of the bore) without sampling artifacts. In particular, we perform reconstructions from noisy projection data obtained for an activity and scanning time similar to standard protocols for the three applications, and the resulting images indicate the possibility of using the proposed systems in practice.

  12. Initial experience with SPECT (single-photon computerized tomography) of the brain using N-isopropyl I-123 p-iodoamphetamine: concise communication

    SciTech Connect

    Hill, T.C.; Holman, B.L.; Lovett, R.; O'Leary, D.H.; Front, D.; Magistretti, P.; Zimmerman, R.E.; Moore, S.; Clouse, M.E.; Wu, J.L.; Lin, T.H.; Baldwin, R.M.

    1982-03-01

    Forty-six patients were studied with N-isopropyl I-123 p-iodoamphetamine (IMP) and the Harvard Scanning Multidetector Brain System. In nine control patients, good differentiation between the gray and white matter of the cerebral cortex and the basal ganglia was evident. Regional uptake was affected by physiologic maneuvers (visual stimulation). In 24 patients studied for stroke, IMP images demonstrated areas that were involved in acute infarction in eight patients whose initial transmission computerized tomography (TCT) was normal; IMP also showed perfusion abnormalities larger than the TCT abnormality in ten patients. Perfusion abnormalities were present in 23/24 of these patients. Seven patients studied with a history of TIA had normal TCT and IMP images. In three patients studied during seizure activity, regions of hyperperfusion corresponded to the EEG seizure focus. Markedly decreased activity was present in three patients with brain tumor and corresponded to the focal abnormality on the TCT study. Our study demonstrates the feasibility of assessing regional brain perfusion using a radiopharmaceutical that is lipid soluble and has a high extraction fraction in the brain, together with single-photon ECT.

  13. Radiopharmaceuticals for SPECT cancer detection

    NASA Astrophysics Data System (ADS)

    Chernov, V. I.; Medvedeva, A. A.; Zelchan, R. V.; Sinilkin, I. G.; Stasyuk, E. S.; Larionova, L. A.; Slonimskaya, E. M.; Choynzonov, E. L.

    2016-08-01

    The purpose of the study was to assess the efficacy of single photon emission computed tomography (SPECT) with 199Tl and 99mTc-MIBI in the detection of breast, laryngeal and hypopharyngeal cancers. A total of 220 patients were included into the study: 120 patients with breast lesions (100 patients with breast cancer and 20 patients with benign breast tumors) and 100 patients with laryngeal/hypopharyngeal diseases (80 patients with laryngeal/hypopharyngeal cancer and 20 patients with benign laryngeal/hypopharyngeal lesions). No abnormal 199Tl uptake was seen in all patients with benign breast and laryngeal lesions, indicating a 100% specificity of 199Tl SPECT. In the breast cancer patients, the increased 199Tl uptake in the breast was visualized in 94.8% patients, 99mTc-MIBI—in 93.4% patients. The increased 199Tl uptake in axillary lymph nodes was detected in 60% patients, and 99mTc-MIBI—in 93.1% patients. In patients with laryngeal/hypopharyngeal cancer, the sensitivity of SPECT with 199Tl and 99mTc-MIBI was 95%. The 199Tl SPECT sensitivity in identification of regional lymph node metastases in the patients with laryngeal/hypopharyngeal cancer was 75% and the 99mTc-MIBI SPECT sensitivity was 17%. The data obtained showed that SPECT with 199Tl and 99mTc-MIBI can be used as one of the additional imaging methods in detection of tumors.

  14. Radiopharmaceuticals for SPECT Cancer Detection

    NASA Astrophysics Data System (ADS)

    Chernov, V. I.; Medvedeva, A. A.; Zelchan, R. V.; Sinilkin, I. G.; Stasyuk, E. S.; Larionova, L. A.; Slonimskaya, E. M.; Choynzonov, E. L.

    2016-06-01

    The purpose of the study was to assess the efficacy of single photon emission computed tomography (SPECT) with 199Tl and 99mTc-MIBI in the detection of breast, laryngeal and hypopharyngeal cancers. Materials and Methods: a total of 220 patients were included into the study. Of them, there were 120 patients with breast lesions (100 patients with breast cancer and 20 patients with benign breast tumors) and '00 patients with laryngeal/hypopharyngeal diseases (80 patients with laryngeal/hypopharyngeal cancer and 20 patients with benign laryngeal/hypopharyngeal lesions). Results: no abnormal 199Tl uptake was seen in all patients with benign breast and laryngeal lesions, indicating a 100% specificity of 199Tl SPECT. In breast cancer patients, increased 199Tl uptake in the breast was visualized in 94.8% patients, 99mTc-MIBI in 93.4% patients. Increased 199Tl uptake in axillary lymph nodes was detected in 60% patients and 99mTc-MIBI in 93.1% patients. In patients with laryngeal/hypopharyngeal cancer, sensitivity of SPECT with 199Tl and 99mTc-MIBI were 95%. The 199Tl SPECT sensitivity in identification of regional lymph node metastases in patients with laryngeal/hypopharyngeal cancer was 75% and the 99mTc-MIBI SPECT sensitivity was 17%. Conclusion: the data obtained show that SPECT with 199Tl and 99mTc-MIBI can be used as one of the additional imaging methods in detection of tumors.

  15. PET and SPECT studies in Parkinson's disease.

    PubMed

    Brooks, D J

    1997-04-01

    Positron emission tomography (PET) and single photon emission tomography (SPECT) provide sensitive means for quantifying the loss of nigrostriatal dopaminergic fibres in Parkinson's disease and for detecting the presence of dopaminergic dysfunction in asymptomatic at-risk relatives and patients with isolated tremor. Functional imaging can also be used to follow the rate of disease progression objectively, determine the efficacy of putative neuroprotective agents, and monitor the viability of transplants of fetal tissue. Additionally, in vivo pharmacological changes associated with development of treatment complications (fluctuations, dyskinesias) can be studied. Loss of dopaminergic projections produces profound changes in resting and activated brain metabolism. PET and SPECT activation studies have suggested that the akinesia of Parkinson's disease is associated with failure to activate the supplementary motor and dorsal pre-frontal areas. Activation of these cortical areas is restored towards normal by the use of dopaminergic medication, striatal transplantation with fetal mesencephalic tissue, and pallidotomy. The aim of this chapter is to review the insight which functional imaging has given us into the pathophysiology of parkinsonism.

  16. Brain perfusion imaging under acetazolamide challenge for detection of impaired cerebrovascular reserve capacity: positive findings with O-15-water PET in patients with negative Tc-99m-HMPAO SPECT.

    PubMed

    Acker, Güliz; Lange, Catharina; Schatka, Imke; Pfeifer, Andreas; Czabanka, Marcus A; Vajkoczy, Peter; Buchert, Ralph

    2017-07-20

    Cerebrovascular reserve capacity (CVRC) is an important parameter for treatment decisions in chronic cerebrovascular diseases. It can be assessed by measuring the acetazolamide-induced change of regional cerebral blood flow using single photon emission computed tomography (SPECT) with Tc-99m-labeled hexamethylpropyleneamine oxime (HMPAO) or positron emission tomography (PET) with O-15-water. Methods: Our database was searched for patients with moyamoya vasculopathy (MMV) or atherosclerotic cerebrovascular disease who had underwent O-15-water PET after normal Tc-99m-HMPAO SPECT with respect to CVRC. O-15-water PET was analyzed visually and quantitatively. Quantitative analysis was based on parametric CVRC maps generated by voxel-wise image subtraction. Results: The search identified 18 patients (43±15y, 12 MMV). PET revealed impaired CVRC in 8 patients (44%). Quantitative analysis confirmed the positive visual findings in O-15-water PET and the negative findings in Tc-99m-HMPAO SPECT. Conclusion: O-15-water PET enables detection of impaired CVRC in a considerable fraction of symptomatic patients with steno-occlusion and negative Tc-99m-HMPAO SPECT. Copyright © 2017 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  17. SPECT imaging with resolution recovery

    SciTech Connect

    Bronnikov, A. V.

    2011-07-01

    Single-photon emission computed tomography (SPECT) is a method of choice for imaging spatial distributions of radioisotopes. Many applications of this method are found in nuclear industry, medicine, and biomedical research. We study mathematical modeling of a micro-SPECT system by using a point-spread function (PSF) and implement an OSEM-based iterative algorithm for image reconstruction with resolution recovery. Unlike other known implementations of the OSEM algorithm, we apply en efficient computation scheme based on a useful approximation of the PSF, which ensures relatively fast computations. The proposed approach can be applied with the data acquired with any type of collimators, including parallel-beam fan-beam, cone-beam and pinhole collimators. Experimental results obtained with a micro SPECT system demonstrate high efficiency of resolution recovery. (authors)

  18. Reduced 123I Ioflupane Binding in Bilateral Diabetic Chorea: Findings With 18F FDG PET, 99mTc ECD SPECT, and 123I MIBG Scintigraphy.

    PubMed

    Sato, Kenichiro; Hida, Ayumi; Kameyama, Masashi; Morooka, Miyako; Takeuchi, Sousuke

    2016-06-01

    We report a 64-year-old man with diabetic chorea whom we investigated with dopamine transporter SPECT, F FDG PET, Tc ethylcysteinate dimer (ECD) SPECT, and I metaiodobenzylguanidine (MIBG) scintigraphy. Dopamine transporter SPECT revealed reduced I ioflupane binding in the bilateral striatum. F FDG PET showed metabolic dysfunction in the bilateral striatum, as shown in earlier studies. Tc ECD SPECT revealed reduced brain perfusion in the bilateral caudate nucleus and putamen. I MIBG scintigraphy revealed no cardiac sympathetic nerve dysfunction. Our case suggests a possible nigrostriatal presynaptic dopaminergic involvement in diabetic chorea.

  19. Radiopharmaceuticals for SPECT cancer detection

    SciTech Connect

    Chernov, V. I. Medvedeva, A. A. Zelchan, R. V. Sinilkin, I. G.; Stasyuk, E. S.; Larionova, L. A.; Slonimskaya, E. M.; Choynzonov, E. L.

    2016-08-02

    The purpose of the study was to assess the efficacy of single photon emission computed tomography (SPECT) with {sup 199}Tl and {sup 99}mTc-MIBI in the detection of breast, laryngeal and hypopharyngeal cancers. A total of 220 patients were included into the study: 120 patients with breast lesions (100 patients with breast cancer and 20 patients with benign breast tumors) and 100 patients with laryngeal/hypopharyngeal diseases (80 patients with laryngeal/hypopharyngeal cancer and 20 patients with benign laryngeal/hypopharyngeal lesions). No abnormal {sup 199}Tl uptake was seen in all patients with benign breast and laryngeal lesions, indicating a 100% specificity of {sup 199}Tl SPECT. In the breast cancer patients, the increased {sup 199}Tl uptake in the breast was visualized in 94.8% patients, {sup 99m}Tc-MIBI—in 93.4% patients. The increased {sup 199}Tl uptake in axillary lymph nodes was detected in 60% patients, and {sup 99m}Tc-MIBI—in 93.1% patients. In patients with laryngeal/hypopharyngeal cancer, the sensitivity of SPECT with {sup 199}Tl and {sup 99m}Tc-MIBI was 95%. The {sup 199}Tl SPECT sensitivity in identification of regional lymph node metastases in the patients with laryngeal/hypopharyngeal cancer was 75% and the {sup 99m}Tc-MIBI SPECT sensitivity was 17%. The data obtained showed that SPECT with {sup 199}Tl and {sup 99m}Tc-MIBI can be used as one of the additional imaging methods in detection of tumors.

  20. Iterative restoration of SPECT projection images

    NASA Astrophysics Data System (ADS)

    Glick, S. J.; Xia, Weishi

    1997-04-01

    Photon attenuation and the limited nonstationary spatial resolution of the detector can reduce both qualitative and quantitative image quality in single photon emission computed tomography (SPECT). In this paper, a reconstruction approach is described which can compensate for both of these degradations. The approach involves processing the projection data with Bellini's method for attenuation compensation followed by an iterative deconvolution technique which uses the frequency distance principle (FDP) to model the distance-dependent camera blur. Modeling of the camera blur with the FDP allows an efficient implementation using fast Fourier transform (FFT) methods. After processing of the projection data, reconstruction is performed using filtered backprojection. Simulation studies using two different brain phantoms show that this approach gives reconstructions with a favorable bias versus noise tradeoff, provides no visually undesirable noise artifacts, and requires a low computational load.

  1. [Utility of SPECT in gallium scintigraphy].

    PubMed

    Uto, Tomoyuki

    2002-11-01

    Whole-body gallium planar scintigraphy is a mainstay for the detection of tumors and inflammatory lesions. Recently, gallium SPECT (single photon emission computed tomography) has become more common in the clinical setting. This diagnostic modality is widely employed in our hospital, and lesions are actually detected by SPECT in some cases. Although the contrast of SPECT images is better than that of planar images, spatial resolution is limited by the limited matrix size. Thus, the overall diagnostic utility of SPECT remains to be confirmed. The usefulness of SPECT for the detection of gallium-accumulated lesions was evaluated in a phantom. In this study, we showed that SPECT is able to detect more smaller and lower gallium accumulations than planar imaging. Thus, SPECT imaging is useful in gallium scintigraphy.

  2. Perfusion SPECT, SISCOM and PET (18)F-FDG in the assessment of drug- refractory epilepsy patients candidates for epilepsy surgery.

    PubMed

    Suárez-Piñera, M; Mestre-Fusco, A; Ley, M; González, S; Medrano, S; Principe, A; Mojal, S; Conesa, G; Rocamora, R

    2015-01-01

    Brain perfusion SPECT (ictal-interictal), SPECT images and subtraction ictal SPECT coregistered to MRI (SISCOM) and (18)F-FDG-PET (interictal), play an important role in the pre-surgical diagnosis of patients with medically refractory epilepsy. This study aimed to establish: the reproducibility of visual ictal-interictal SPECT and SISCOM analysis altogether with the capacity of SPECT, SISCOM and PET to determine the epileptogenic zone. (99m)Tc-HMPAO SPECT ictal-interictal and SISCOM (Analyze 7.0) were performed on 47 refractory epilepsy patients (24 F, 19-60 yrs). In 13 patients, SISCOM was also performed using a new program (Focus DET). Ictal-interictal SPECT and SISCOM images were analysed independently by two nuclear medicine physicians (observer 1 and 2). Kappa concordance coefficient was used to evaluate the reproducibility. In sixteen patients, SPECT, SISCOM and PET findings were compared with the resected area during the surgery, and surgical outcome using Engel scale or with the stereo EEG-(SEEG). The ictal-interictal SPECT interobserver agreement was 91%, Kappa index 0.86, SISCOM (Analyze 7.0) interobserver agreement percentage was 82%, Kappa index 0.80, Analyze 7.0 showed a higher inconclusive results than visual SPECT analysis. SISCOM FocusDET interobserver agreement was 92%, Kappa index 0.87, with lower inconclusive results than Analyze 7.0. SPECT, SISCOM and PET combined findings identified 87% seizure onset zone: 79% temporal, 26% parieto-temporal and 7% frontal. Ictal-interictal SPECT and SISCOM showed a high reproducibility in this sample of patients with drug-refractory epilepsy. SPECT,SISCOM and PET combined findings improved detection of epileptogenic zone in comparison with the individual assessment. Copyright © 2015 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

  3. Cerebral infarction on 99mTc-MDP SPECT/CT imaging.

    PubMed

    Guo, Jia; Hu, Shuang; Wang, Haitao; Kuang, Anren

    2013-11-01

    A 70-year-old man with lung cancer underwent whole-body MDP bone scintigraphy to evaluate bone metastases that showed marked tracer uptake in the right side of the head, suggestive of skull metastasis. SPECT/CT imaging was performed for further evaluation. The SPECT images demonstrated increased MDP activity in the region of the brain perfused by the right middle cerebral artery. On CT images, there was a large hypoattenuation area corresponding to elevated MDP accumulation. At the same day, magnetic resonance angiography of the brain revealed occlusion of the right middle cerebral artery.

  4. Single photon emission photography/magnetic resonance imaging (SPECT/MRI) visualization for frontal-lobe-damaged regions

    NASA Astrophysics Data System (ADS)

    Stokking, Rik; Zuiderveld, Karel J.; Hulshoff Pol, Hilleke E.; Viergever, Max A.

    1994-09-01

    We present multi-modality visualization strategies to convey information contained in registered Single Photon Emission Photography (SPECT) and Magnetic Resonance (MR) images of the brain. Multi-modality visualization provides a means to retrieve valuable information from the data which might otherwise remain obscured. Here we use MRI as an anatomical framework for functional information acquired with SPECT. This is part of clinical research studying the change of functionality caused by a frontal lobe damaged region. A number of known and newly developed techniques for the integrated visualization of SPECT and MR images will be discussed.

  5. Non-ketotic hyperglycaemic chorea: a SPECT study.

    PubMed

    Chang, M H; Li, J Y; Lee, S R; Men, C Y

    1996-04-01

    To study regional blood flow of the striatum in non-ketotic hyperglycaemic choreic patients. Brain SPECT was performed with intravenous injection of 20 mCi 99mTc hexamethylpropylene amineoxime in six non-ketotic hyperglycaemic choreic patients and 10 age matched patients with a similar level of hyperglycaemia without chorea as a control. The focal perfusion defects were analysed by visual interpretation and semiquantitative determination with reference to homolateral occipital blood flow. The measured blood flow of striatum on the contralateral side of chorea was significantly decreased. Hypometabolism of the striatum is seen not only in Huntington's disease, but also in non-ketotic hyperglycaemic chorea. Hypofunction of the striatum is a possible common pathogenesis in the development of contralateral chorea in different diseases. Furthermore, the sensitivity and reliability of SPECT is as good as PET in assessing choreic patients.

  6. SPECT (Single-Photon Emission Computerized Tomography) Scan

    MedlinePlus

    SPECT scan Overview By Mayo Clinic Staff A single-photon emission computerized tomography (SPECT) scan lets your doctor analyze the function of some of your internal organs. A SPECT scan is a type of nuclear imaging test, ...

  7. Combining SPECT and Quantitative EEG Analysis for the Automated Differential Diagnosis of Disorders with Amnestic Symptoms

    PubMed Central

    Höller, Yvonne; Bathke, Arne C.; Uhl, Andreas; Strobl, Nicolas; Lang, Adelheid; Bergmann, Jürgen; Nardone, Raffaele; Rossini, Fabio; Zauner, Harald; Kirschner, Margarita; Jahanbekam, Amirhossein; Trinka, Eugen; Staffen, Wolfgang

    2017-01-01

    Single photon emission computed tomography (SPECT) and Electroencephalography (EEG) have become established tools in routine diagnostics of dementia. We aimed to increase the diagnostic power by combining quantitative markers from SPECT and EEG for differential diagnosis of disorders with amnestic symptoms. We hypothesize that the combination of SPECT with measures of interaction (connectivity) in the EEG yields higher diagnostic accuracy than the single modalities. We examined 39 patients with Alzheimer's dementia (AD), 69 patients with depressive cognitive impairment (DCI), 71 patients with amnestic mild cognitive impairment (aMCI), and 41 patients with amnestic subjective cognitive complaints (aSCC). We calculated 14 measures of interaction from a standard clinical EEG-recording and derived graph-theoretic network measures. From regional brain perfusion measured by 99mTc-hexamethyl-propylene-aminoxime (HMPAO)-SPECT in 46 regions, we calculated relative cerebral perfusion in these patients. Patient groups were classified pairwise with a linear support vector machine. Classification was conducted separately for each biomarker, and then again for each EEG- biomarker combined with SPECT. Combination of SPECT with EEG-biomarkers outperformed single use of SPECT or EEG when classifying aSCC vs. AD (90%), aMCI vs. AD (70%), and AD vs. DCI (100%), while a selection of EEG measures performed best when classifying aSCC vs. aMCI (82%) and aMCI vs. DCI (90%). Only the contrast between aSCC and DCI did not result in above-chance classification accuracy (60%). In general, accuracies were higher when measures of interaction (i.e., connectivity measures) were applied directly than when graph-theoretical measures were derived. We suggest that quantitative analysis of EEG and machine-learning techniques can support differentiating AD, aMCI, aSCC, and DCC, especially when being combined with imaging methods such as SPECT. Quantitative analysis of EEG connectivity could become an

  8. Dual Isotope SPECT Study With Epilepsy Patients Using Semiconductor SPECT System.

    PubMed

    Shiga, Tohru; Suzuki, Atsuro; Sakurai, Kotarou; Kurita, Tsugiko; Takeuchi, Wataru; Toyonaga, Takuya; Hirata, Kenji; Kobashi, Keiji; Katoh, Chietsugu; Kubo, Naoki; Tamaki, Nagara

    2017-09-01

    We developed a prototype CdTe SPECT system with 4-pixel matched collimator for brain study. This system provides high-energy-resolution (6.6%), high-sensitivity (220 cps/MBq/head), and high-spatial-resolution images. The aim of this study was to evaluate dual-isotope study of CBF and central benzodiazepine receptor (BZR) images using Tc-ECD and I-IMZ with the new SPECT system in patients with epilepsy comparing with single-isotope study using the conventional scintillation gamma camera. This study included 13 patients with partial epilepsy. The BZR images were acquired at 3 hours after I-IMZ injection for 20 minutes. The images of IMZ were acquired with a conventional 3-head scintillation gamma camera. After BZR image acquisition with the conventional camera, Tc-ECD was injected, and CBF and BZR images were acquired simultaneously 5 minutes after ECD injection with the new SPECT system. The CBF images were also acquired with the conventional camera on separate days. The findings were visually analyzed, and 3D-SSP maximum Z scores of lesions were compared between the 2 studies. There were 47 abnormal lesions on BZR images and 60 abnormal lesions on CBF images in the single-isotope study with the conventional camera. Dual-isotope study with the new system showed concordant abnormal findings of 46 of 47 lesions on BZR and 54 of 60 lesions on CBF images with the single-isotope study with the conventional camera. There was high agreement between the 2 studies in both BZR and CBF findings (Cohen κ values = 0.96 for BZR and 0.78 for CBF). In semiquantitative analysis, maximum Z scores of dual-isotope study with the new system strongly correlated with those of single-isotope study with the conventional camera (BZR: r = 0.82, P < 0.05, CBF: r = 0.87, P < 0.05). Our new SPECT system permits dual-isotope study for pixel-by-pixel analysis of CBF and BZR information with the same pathophysiological condition in patients with epilepsy.

  9. Evaluation of MR perfusion abnormalities in organophosphorus poisoning and its correlation with SPECT.

    PubMed

    Bhanu, K Uday; Khandelwal, Niranjan; Vyas, Sameer; Singh, Paramjeet; Prabhakar, Anuj; Mittal, B R; Bhalla, Ashish

    2017-01-01

    Acute organophosphate (OP) pesticide poisoning causes substantial morbidity and mortality worldwide. Many imaging modalities, such as computerized tomography (CT), magnetic resonance imaging (MRI), and single photon emission computed tomography (SPECT) of the brain, have been used for quantitative assessment of the acute brain insult caused by acute OP poisoning. Perfusion defects on SPECT in acutely poisoned patients with OPs have been described, however, MR perfusion abnormalities have not been described in the literature. MR perfusion Imaging has the advantage of having higher spatial resolution, no radiation, and better availability. In this prospective study, 20 patients who ingested OP compounds were included. All the patients underwent brain SPECT on a dual head SPECT gamma camera and MRI brain on a 1.5T MR system. Neurocognitive tests were performed for all patients. SPECT showed perfusion defects in 7 patients and total number of perfusion defects were 29. On MR perfusion, based on the cut-off values of normalized cerebral blood volume (nCBV) ratios and normalized cerebral blood flow (nCBF) ratios, the total number of patients showing perfusion defects were 6 and 8; and the total number of perfusion defects were 29 and 45, respectively. There was significant difference of the nCBV ratios and nCBF ratios between the control group (n = 20) and positive patients group (n = 6 and n = 8, respectively) (P > 0.05). All the defects seen on SPECT were well appreciated on nCBF maps (MRI perfusion) suggestive of 100% correlation. MR perfusion imaging can be used as an effective modality for evaluation in acute OP poisoning.

  10. [SPECT radiopharmaceuticals -- novelties and new possibilities].

    PubMed

    Balogh, Lajos; Polyák, András; Pöstényi, Zita; Haász, Veronika; Dabasi, Gabriella; Jóba, Róbert; Bús, Katalin; Jánoki, Gergely; Thuróczy, Julianna; Zámbó, Katalin; Garai, Ildikó; Környei, József; Jánoki, Gyõzõ

    2014-12-01

    Actual state of affairs and future perspectives of SPECT radiopharmaceuticals regarding local and international data were summarized. Beyond conventional gamma-emitting radioisotopes, localization studies with beta emitting therapeutic radiopharmaceuticals hold increasing importance. Extension of hybrid (SPECT/CT) equipments has modified conventional scintigraphic and SPECT methods as well but more important changes come into the world through novel ligands for specific diagnoses and therapy.

  11. Organ volume estimation using SPECT

    SciTech Connect

    Zaidi, H.

    1996-06-01

    Knowledge of in vivo thyroid volume has both diagnostic and therapeutic importance and could lead to a more precise quantification of absolute activity contained in the thyroid gland. In order to improve single-photon emission computed tomography (SPECT) quantitation, attenuation correction was performed according to Chang`s algorithm. The dual window method was used for scatter subtraction. The author used a Monte Carlo simulation of the SPECT system to accurately determine the scatter multiplier factor k. Volume estimation using SPECT was performed by summing up the volume elements (voxels) lying within the contour of the object, determined by a fixed threshold and the gray level histogram (GLH) method. Thyroid phantom and patient studies were performed and the influence of (1) fixed thresholding, (2) automatic thresholding, (3) attenuation, (4) scatter, and (5) reconstruction filter were investigated. This study shows that accurate volume estimation of the thyroid gland is feasible when accurate corrections are performed. The relative error is within 7% for the GLH method combined with attenuation and scatter corrections.

  12. Physiological imaging with PET and SPECT in Dementia

    SciTech Connect

    Jagust, W.J. . Dept. of Neurology Lawrence Berkeley Lab., CA )

    1989-10-01

    Dementia is a medical problem of increasingly obvious importance. The most common cause of dementia, Alzheimer's disease (AD) accounts for at least 50% of all cases of dementia, with multi-infarct dementia the next most common cause of the syndrome. While the accuracy of diagnosis of AD may range from 80 to 90%, there is currently no laboratory test to confirm the diagnosis. Functional imaging techniques such as positron emission tomography (PET) and single photon emission computed tomography (SPECT) offer diagnostic advantages since brain function is unequivocally disturbed in all dementing illnesses. Both PET and SPECT have been utilized in the study of dementia. While both techniques rely on principles of emission tomography to produce three dimensional maps of injected radiotracers, the differences between positron and single photon emission have important consequences for the practical applications of the two procedures. This briefly reviews the technical differences between PET and SPECT, and discusses how both techniques have been used in our laboratory to elucidate the pathophysiology of dementia. 32 refs., 2 figs.

  13. A method of analysis of SPECT blood flow image data for comparison with computed tomography

    SciTech Connect

    Mountz, J.M.

    1989-03-01

    A consistent method for the qualitative analysis of regional cerebral blood flow on single-photon emission computed tomography (SPECT) imaging has not yet been realized. Regional analysis usually refers an area of abnormal tracer uptake to another region of brain (e.g., the contralateral hemisphere), but region of interest size and analysis differ between investigators. In patients who have had a stroke, the flow deficit size on the SPECT image often appears much larger than the abnormality visualized on computed tomography (CT), and confounds attempts to differentiate between ''purely'' infarcted brain tissue, ischemic brain tissue, edema, or brain tissue having diminution of flow resulting from deafferentation. The author presents a method to determine a flow deficit volume that can be easily calculated from the SPECT image, which yields a volume size that is equivalent to a hypothetical volume having zero blood flow. The method of calculation is objective, independent of region of interest size, and provides a SPECT volume deficit that may be correlated with the CT volume deficit, thus helping to differentiate ''purely'' infarcted tissue from tissue having infarction, edema, ischemia, and deafferentation.

  14. Lymphoma: evaluation with Ga-67 SPECT

    SciTech Connect

    Tumeh, S.S.; Rosenthal, D.S.; Kaplan, W.D.; English, R.J.; Holman, B.L.

    1987-07-01

    To determine the value of gallium-67 single photon emission computed tomography (SPECT) in imaging patients with lymphoma, the authors compared Ga-67 planar images and SPECT images in 40 consecutive patients, using radiologic examinations and/or medical records to confirm the presence or absence of disease. Thirty-three patients had Hodgkin disease, and seven had non-Hodgkin lymphoma. Fifty-four examinations were performed. Of 57 sites of lymphoma in the chest, planar imaging depicted 38, while SPECT depicted 55, resulting in sensitivities of 0.66 and 0.96 for planar and SPECT imaging, respectively. In eight sites, both modalities were truly negative, but SPECT was negative in four additional sites that were equivocal on planar imaging, resulting in specificities of 0.66 and 1.00 for planar and SPECT imaging, respectively. In the abdomen, the sensitivities of planar and SPECT imaging were 0.69 and 0.85, and the specificities 0.87 and 1.00, respectively. SPECT was more accurate in depicting foci of gallium-avid lymphoma in the chest and abdomen and in excluding disease when planar imaging was equivocal.

  15. Mapping the distribution of amobarbital sodium in the intracarotid Wada test by use of Tc-99m HMPAO with SPECT.

    PubMed

    Jeffery, P J; Monsein, L H; Szabo, Z; Hart, J; Fisher, R S; Lesser, R P; Debrun, G M; Gordon, B; Wagner, H N; Camargo, E E

    1991-03-01

    The intracarotid amobarbital sodium, or Wada, test has been used to localize speech and memory function prior to surgical treatment of temporal lobe seizures. The authors mixed technetium-99m hexamethyl-propyleneamine oxime (HMPAO) with amobarbital sodium and injected the mixture in 25 patients with epilepsy. Single photon emission computed tomography (SPECT) of the brain was then performed to determine intracerebral distribution of the amobarbital sodium. Results of SPECT were compared with those of conventional and digital subtraction angiography (DSA). The distribution of Tc-99m HMPAO and, presumably, amobarbital sodium varied from patient to patient. SPECT revealed a statistically different distribution from that predicted with conventional angiography. The distribution also often differed from that of DSA, although the difference was not significant. SPECT revealed infrequent delivery to mesial temporal lobe structures. This emphasizes the need for caution in the use of the intracarotid amobarbital sodium test to predict the outcome of removal of these areas.

  16. Clinical utility of MRI and SPECT in the diagnosis of cognitive impairment referred to memory clinic.

    PubMed

    Guinane, John; Ng, Boon Lung

    2017-09-07

    Despite of their limited availability and potential for significant variation between and within each modality, this is the first study to prospectively measure the clinical utility of MRI and/or SPECT brain scanning in addition to the routine diagnostic workup of patients presenting to memory clinic. A single center study was conducted over a convenience of 12-month sampling period. For each patient referred for MRI and/or SPECT scanning, the primary geriatrician or psychogeriatrician was asked to assign an initial diagnosis. The initial diagnosis was then compared with the final consensus diagnosis after any scans or neuropsychology testing had been completed. During the 12-month study period, 66 patients (26%) were referred for scans out of a total of 253 patients included in the study. There were 16/44 (36%) positive MRI outcomes and 13/35 (37%) positive SPECT outcomes. The diagnosis changed consistent with the MRI scan findings in 11/44 (25%) and changed consistent with the SPECT scan findings in 9/35 (26%). Potentially reversible pathology was identified in a single patient, 1/50 (2%), via an MRI scan that suggested normal pressure hydrocephalus. The number needed to test for one positive outcome was 3.8 (95% CI 2.0-23.3), 6.0 (95% CI NA), and 1.7 (95% CI 1.3-2.5) for MRI only, SPECT only, and MRI and SPECT together, respectively. The clinical utility of MRI and/or SPECT scanning in this study may be broadly superior to the available international evidence, and further research is needed to identify predictors of positive scan outcomes.

  17. Drug Development in Alzheimer’s Disease: The Contribution of PET and SPECT

    PubMed Central

    Declercq, Lieven D.; Vandenberghe, Rik; Van Laere, Koen; Verbruggen, Alfons; Bormans, Guy

    2016-01-01

    Clinical trials aiming to develop disease-altering drugs for Alzheimer’s disease (AD), a neurodegenerative disorder with devastating consequences, are failing at an alarming rate. Poorly defined inclusion-and outcome criteria, due to a limited amount of objective biomarkers, is one of the major concerns. Non-invasive molecular imaging techniques, positron emission tomography and single photon emission (computed) tomography (PET and SPE(C)T), allow visualization and quantification of a wide variety of (patho)physiological processes and allow early (differential) diagnosis in many disorders. PET and SPECT have the ability to provide biomarkers that permit spatial assessment of pathophysiological molecular changes and therefore objectively evaluate and follow up therapeutic response, especially in the brain. A number of specific PET/SPECT biomarkers used in support of emerging clinical therapies in AD are discussed in this review. PMID:27065872

  18. C-SPECT - a Clinical Cardiac SPECT/Tct Platform: Design Concepts and Performance Potential

    PubMed Central

    Chang, Wei; Ordonez, Caesar E.; Liang, Haoning; Li, Yusheng; Liu, Jingai

    2013-01-01

    Because of scarcity of photons emitted from the heart, clinical cardiac SPECT imaging is mainly limited by photon statistics. The sub-optimal detection efficiency of current SPECT systems not only limits the quality of clinical cardiac SPECT imaging but also makes more advanced potential applications difficult to be realized. We propose a high-performance system platform - C-SPECT, which has its sampling geometry optimized for detection of emitted photons in quality and quantity. The C-SPECT has a stationary C-shaped gantry that surrounds the left-front side of a patient’s thorax. The stationary C-shaped collimator and detector systems in the gantry provide effective and efficient detection and sampling of photon emission. For cardiac imaging, the C-SPECT platform could achieve 2 to 4 times the system geometric efficiency of conventional SPECT systems at the same sampling resolution. This platform also includes an integrated transmission CT for attenuation correction. The ability of C-SPECT systems to perform sequential high-quality emission and transmission imaging could bring cost-effective high-performance to clinical imaging. In addition, a C-SPECT system could provide high detection efficiency to accommodate fast acquisition rate for gated and dynamic cardiac imaging. This paper describes the design concepts and performance potential of C-SPECT, and illustrates how these concepts can be implemented in a basic system. PMID:23885129

  19. Feasibility of a CdTe-based SPECT for high-resolution low-dose small animal imaging: a Monte Carlo simulation study

    NASA Astrophysics Data System (ADS)

    Park, S.-J.; Yu, A. R.; Lee, Y.-J.; Kim, Y.-s.; Kim, H.-J.

    2014-07-01

    Dedicated single-photon-emission computed tomography (SPECT) systems based on pixelated semiconductors such as cadmium telluride (CdTe) are in development to study small animal models of human disease. In an effort to develop a high-resolution, low-dose system for small animal imaging, we compared a CdTe-based SPECT system and a conventional NaI(Tl)-based SPECT system in terms of spatial resolution, sensitivity, contrast, and contrast-to-noise ratio (CNR). In addition, we investigated the radiation absorbed dose and calculated a figure of merit (FOM) for both SPECT systems. Using the conventional NaI(Tl)-based SPECT system, we achieved a spatial resolution of 1.66 mm at a 30 mm source-to-collimator distance, and a resolution of 2.4-mm hot-rods. Using the newly-developed CdTe-based SPECT system, we achieved a spatial resolution of 1.32 mm FWHM at a 30 mm source-to-collimator distance, and a resolution of 1.7-mm hot-rods. The sensitivities at a 30 mm source-to-collimator distance were 115.73 counts/sec/MBq and 83.38 counts/sec/MBq for the CdTe-based SPECT and conventional NaI(Tl)-based SPECT systems, respectively. To compare quantitative measurements in the mouse brain, we calculated the CNR for images from both systems. The CNR from the CdTe-based SPECT system was 4.41, while that from the conventional NaI(Tl)-based SPECT system was 3.11 when the injected striatal dose was 160 Bq/voxel. The CNR increased as a function of injected dose in both systems. The FOM of the CdTe-based SPECT system was superior to that of the conventional NaI(Tl)-based SPECT system, and the highest FOM was achieved with the CdTe-based SPECT at a dose of 40 Bq/voxel injected into the striatum. Thus, a CdTe-based SPECT system showed significant improvement in performance compared with a conventional system in terms of spatial resolution, sensitivity, and CNR, while reducing the radiation dose to the small animal subject. Herein, we discuss the feasibility of a CdTe-based SPECT system for high

  20. Global scaling for semi-quantitative analysis in FP-CIT SPECT.

    PubMed

    Kupitz, D; Apostolova, I; Lange, C; Ulrich, G; Amthauer, H; Brenner, W; Buchert, R

    2014-01-01

    Semi-quantitative characterization of dopamine transporter availability from single photon emission computed tomography (SPECT) with 123I-ioflupane (FP-CIT) is based on uptake ratios relative to a reference region. The aim of this study was to evaluate the whole brain as reference region for semi-quantitative analysis of FP-CIT SPECT. The rationale was that this might reduce statistical noise associated with the estimation of non-displaceable FP-CIT uptake. 150 FP-CIT SPECTs were categorized as neurodegenerative or non-neurodegenerative by an expert. Semi-quantitative analysis of specific binding ratios (SBR) was performed with a custom-made tool based on the Statistical Parametric Mapping software package using predefined regions of interest (ROIs) in the anatomical space of the Montreal Neurological Institute. The following reference regions were compared: predefined ROIs for frontal and occipital lobe and whole brain (without striata, thalamus and brainstem). Tracer uptake in the reference region was characterized by the mean, median or 75th percentile of its voxel intensities. The area (AUC) under the receiver operating characteristic curve was used as performance measure. The highest AUC of 0.973 was achieved by the SBR of the putamen with the 75th percentile in the whole brain as reference. The lowest AUC for the putamen SBR of 0.937 was obtained with the mean in the frontal lobe as reference. We recommend the 75th percentile in the whole brain as reference for semi-quantitative analysis in FP-CIT SPECT. This combination provided the best agreement of the semi-quantitative analysis with visual evaluation of the SPECT images by an expert and, therefore, is appropriate to support less experienced physicians.

  1. The AdaptiSPECT Imaging Aperture

    PubMed Central

    Chaix, Cécile; Moore, Jared W.; Van Holen, Roel; Barrett, Harrison H.; Furenlid, Lars R.

    2015-01-01

    In this paper, we present the imaging aperture of an adaptive SPECT imaging system being developed at the Center for Gamma Ray Imaging (AdaptiSPECT). AdaptiSPECT is designed to automatically change its configuration in response to preliminary data, in order to improve image quality for a particular task. In a traditional pinhole SPECT imaging system, the characteristics (magnification, resolution, field of view) are set by the geometry of the system, and any modification can be accomplished only by manually changing the collimator and the distance of the detector to the center of the field of view. Optimization of the imaging system for a specific task on a specific individual is therefore difficult. In an adaptive SPECT imaging system, on the other hand, the configuration can be conveniently changed under computer control. A key component of an adaptive SPECT system is its aperture. In this paper, we present the design, specifications, and fabrication of the adaptive pinhole aperture that will be used for AdaptiSPECT, as well as the controls that enable autonomous adaptation. PMID:27019577

  2. SPECT in the diagnosis of hepatic hemangioma

    SciTech Connect

    Brunetti, J.C.; Van Heertum, R.L.; Yudd, A.P.

    1985-05-01

    Tc99m labeled red blood cell blood flow and delayed static blood pool imaging is widely accepted as a reliable, accurate method for the diagnosis of hepatic hemangiomata. The purpose of this study is to assess the relative value of SPECT blood pool imaging in the evaluation of hepatic hemangionata. A total of 68 patients, including 21 patients with proven hepatic cavernous hemangiomas, were studied using both planar and SPECT imaging techniques. All patients underwent multi-phase evaluation which included a hepatic flow study, immediate planar images of the liver, followed by a 360/sup 0/ tomographic (SPECT) study and subsequent 60 minute delayed static planar hepatic blood pool images. All 21 patients with proven hepatic hemangiomas had a positive SPECT exam and 17 of the 21 (81%) patients had a positive planar exam. In the 21 patients, there were a total of 36 hemangiomas ranging in size from .7 cm to 13 cm. The SPECT imaging technique correctly identified all 36 lesions (100%) where as planar imaging detected 25 of the 36 lesions (69.4%). In all the remaining patients (10-normal, 17-metastatic disease, 12-hepatocellular disease, 6-hepatoma, 2-liver cysts), both the planar and SPECT imaging techniques were interpreted as showing no evidence of focal sequestration of red blood cells. SPECT hepatic blood pool imaging represents an improvement in the evaluation of hepatic hemangioma as a result of a reduction in imaging time (less than thirty minutes), improved spatial resolution and greater overall accuracy.

  3. Brain perfusion single photon emission computed tomography in major psychiatric disorders: From basics to clinical practice

    PubMed Central

    Santra, Amburanjan; Kumar, Rakesh

    2014-01-01

    Brain single photon emission computed tomography (SPECT) is a well-established and reliable method to assess brain function through measurement of regional cerebral blood flow (rCBF). It can be used to define a patient's pathophysiological status when neurological or psychiatric symptoms cannot be explained by anatomical neuroimaging findings. Though there is ample evidence validating brain SPECT as a technique to track human behavior and correlating psychiatric disorders with dysfunction of specific brain regions, only few psychiatrists have adopted brain SPECT in routine clinical practice. It can be utilized to evaluate the involvement of brain regions in a particular patient, to individualize treatment on basis of SPECT findings, to monitor the treatment response and modify treatment, if necessary. In this article, we have reviewed the available studies in this regard from existing literature and tried to present the evidence for establishing the clinical role of brain SPECT in major psychiatric illnesses. PMID:25400359

  4. Integration of AdaptiSPECT, a small-animal adaptive SPECT imaging system

    PubMed Central

    Chaix, Cécile; Kovalsky, Stephen; Kosmider, Matthew; Barrett, Harrison H.; Furenlid, Lars R.

    2015-01-01

    AdaptiSPECT is a pre-clinical adaptive SPECT imaging system under final development at the Center for Gamma-ray Imaging. The system incorporates multiple adaptive features: an adaptive aperture, 16 detectors mounted on translational stages, and the ability to switch between a non-multiplexed and a multiplexed imaging configuration. In this paper, we review the design of AdaptiSPECT and its adaptive features. We then describe the on-going integration of the imaging system. PMID:26347197

  5. SPECT Imaging: Basics and New Trends

    NASA Astrophysics Data System (ADS)

    Hutton, Brian F.

    Single Photon Emission Computed Tomography (SPECT) is widely used as a means of imaging the distribution of administered radiotracers that have single-photon emission. The most widely used SPECT systems are based on the Anger gamma camera, usually involving dual detectors that rotate around the patient. Several factors affect the quality of SPECT images (e.g., resolution and noise) and the ability to perform absolute quantification (e.g., attenuation, scatter, motion, and resolution). There is a trend to introduce dual-modality systems and organ-specific systems, both developments that enhance diagnostic capability.

  6. [The group study of diagnostic efficacy of cerebro-vascular disease by I-123 IMP SPECT images obtained with ring type SPECT scanner--the ROC analysis on the diagnosis of perfusion defect and redistribution].

    PubMed

    Machida, K; Matsumoto, T; Honda, N; Mamiya, T; Takahashi, T; Takishima, T; Kamano, T; Tamaki, S; Iinuma, T A; Tateno, Y

    1991-11-01

    We performed two image reading experiments in order to investigate the diagnostic capability of I-123 IMP SPECT obtained by the ring type SPECT scanner in cerebro-vascular disease. Fourteen physicians diagnosed SPECT images of 55 cases with reference to clinical neurological informations, first without brain XCT images and second with XCT images. Each physician detected perfusion defects and redistributions of I-123 IMP and assigned a confidence level of abnormality for these SPECT findings by means of five rating method. From results obtained by ROC analysis, we concluded as follows: (1) Generally, I-123 IMP SPECT is a stable diagnostic modality in the diagnosis of cerebro-vascular disease and the image reading of XCT had no effects on the diagnosis of SPECT on the whole of physician, (2) However, there were unnegligible differences among individuals in the detectability of findings and the effect of XCT image reading, (3) Detectability of redistribution of I-123 IMP was lower than that of perfusion defect and inter-observer variation in the diagnostic performance for redistribution was larger than that of perfusion defect. The results suggest that it is necessary to standardize diagnostic criteria among physicians for redistribution of I-123 IMP.

  7. SPECT imaging with the long bore collimator: Loss in sensitivity vs improved contrast resolution

    SciTech Connect

    Muller, S.; Polak, J.F.; Holman, B.L.; Eisner, R.L.

    1984-01-01

    A long bore (LB) collimator (16 cm thick) was compared with the standard low energy all purpose (LEAP) collimator for SPECT imaging. Line spread functions at various depths were measured in scatter material (planar imaging). Both collimators have similar full-width-at-half-maximum (FWHM) values yet the LB has less resolution loss with distance and consistently lower full-width-at-tenth-maximum (FWTM) values. An assessment of overall performance was made by planar imaging of the Rollo phantom with both collectors. Performance was judged by calculating the chi-square for the observed and expected contrasts of spherical cold targets (2.54, 1.91, 1.27 and 0.95 cm diameter). In all cases, LB scored consistently better than the LEAP. SPECT imaging of a bar phantom (spacing 2.25 cm) filled with I-123 (p,2n) confirmed the superior contrast resolution of the LB. Using SPECT data from 5 clinical I-123 IMP brain studies and from measurements of % rms noise as a function of total slice counts in a cylindrical phantom, the authors calculate that LB images would have a % rms noise of 8.7% compared to 5.7% for LEAP images acquired over the same time interval. The authors conclude that SPECT of the brain with the LB would lead to improved contrast resolution and a minimal increase in % rms noise despite a significant loss in sensitivity.

  8. Comparison of ( sup 99m Tc)HMPAO SPECT with ( sup 18 F)fluoromethane PET in cerebrovascular disease

    SciTech Connect

    Heiss, W.D.; Herholz, K.; Podreka, I.; Neubauer, I.; Pietrzyk, U. )

    1990-09-01

    Positron emission tomography (PET) of (18F)fluoromethane (FM) and single-photon emission tomography (SPECT) of (99mTc)hexamethylpropyleneamine oxime (HMPAO) were performed under identical conditions within 2 h in 22 patients suffering from cerebrovascular disease (8 ischemic infarction, 2 intracerebral hemorrhages, 7 transient ischemic attacks, and 5 multi-infarct syndrome). While gross pathological changes could be seen in the images of either procedure, focal abnormalities corresponding to transient ischemic deficits or to lesions in multi-infarct syndrome and areas of functional deactivation were sometimes missed on SPECT images. Overall, HMPAO SPECT images showed less contrast between high and low activity regions than the FM PET images, and differences between lesions and contralateral regions were less pronounced (6.4 vs 13.3% difference). Regional cerebral blood flow (rCBF) was calculated from FM PET studies in 14 large territorial regions and the pathological lesion, and the regional values relative to mean flow were compared to the relative HMPAO uptake in an identical set of regions defined on the SPECT images. Among individual patients, the Spearman rank-correlation coefficient between relative rCBF and HMPAO uptake varied between 0.48 and 0.89, with a mean of 0.70. While an underestimation of high flow with SPECT--which was demonstrated in a curvilinear relationship between all relative regional PET and SPECT values--could be corrected by linearization taking into account HMPAO efflux from the brain before metabolic trapping, correspondence of SPECT data with PET rCBF values was not improved since this procedure also increased the variance in high flow areas. In the cerebellum, however, a high HMPAO uptake in SPECT always overestimated CBF in relation to forebrain values; this finding might be due to high capillary density in the cerebellum.

  9. Awake animal SPECT: Overview and initial results

    SciTech Connect

    Weisenberger, A G; Majewski, S; McKisson, J; Popov, V; Proffitt, J; Stolin, A; Baba, J S; Goddard, J S; Lee, S J; Smith, M F; Tsui, B; Pomper, M

    2009-02-01

    A SPECT / X-ray CT system configured at Johns Hopkins University to image the biodistribution of radiopharmaceuticals in unrestrained, un-anesthetized mice has been constructed and tested on awake mice. The system was built by Thomas Jefferson National Accelerator Facility and Oak Ridge National Laboratory. SPECT imaging is accomplished using two gamma cameras, 10 cm × 20 cm in size based on a 2 × 4 array of Hamamatsu H8500 flat panel position sensitive photomultiplier tubes. A real-time optical tracking system utilizing three infrared cameras provides time stamped pose data of an awake mouse head during a SPECT scan. The six degrees of freedom (three translational and three rotational) pose data are used for motion correction during 3-D tomographic list-mode iterative image reconstruction. SPECT reconstruction of awake, unrestrained mice with motion compensation for head movement has been accomplished.

  10. SPECT assay of radiolabeled monoclonal antibodies

    SciTech Connect

    Jaszczak, R.J.

    1992-02-01

    The long-term goal of this research project is to develop methods to improve the utility of single photon emission computed tomography (SPECI) to quantify the biodistribution of monoclonal antibodies (MoAbs) labeled with clinically relevant radionuclides ({sup 123}I, {sup 131}I, and {sup 111}In) and with another radionuclide,{sup 211}At, recently used in therapy. We describe here our progress in developing quantitative SPECT methodology for {sup 111}In and {sup 123}I. We have focused our recent research thrusts on the following aspects of SPECT: (1) The development of improved SPECT hardware, such as improved acquisition geometries. (2) The development of better reconstruction methods that provide accurate compensation for the physical factors that affect SPECT quantification. (3) The application of carefully designed simulations and experiments to validate our hardware and software approaches.

  11. PET/SPECT imaging agents for neurodegenerative diseases

    PubMed Central

    Zhu, Lin; Ploessl, Karl; Kung, Hank F.

    2014-01-01

    Single photon emission computed tomography (SPECT) or positron emission computed tomography (PET) imaging agents for neurodegenerative disease have a significant impact on clinical diagnosis and patient care. The examples of Parkinson’s Disease (PD) and Alzheimer’s Disease (AD) imaging agents described in this paper provide a general view on how imaging agents, ie radioactive drugs, are selected, chemically prepared and applied in humans. Imaging the living human brain can provide unique information on the pathology and progression of neurodegenerative diseases, such as AD and PD. The imaging method will also facilitate preclinical and clinical trials of new drugs offering specific information related to drug binding sites in the brain. In the future, chemists will continue to play important roles in identifying specific targets, synthesizing target-specific probes for screening and ultimately testing them by in vitro and in vivo assays. PMID:24676152

  12. ADAPTIVE SMALL-ANIMAL SPECT/CT

    PubMed Central

    Furenlid, L.R.; Moore, J.W.; Freed, M.; Kupinski, M.A.; Clarkson, E.; Liu, Z.; Wilson, D.W.; Woolfenden, J.M.; Barrett, H.H.

    2015-01-01

    We are exploring the concept of adaptive multimodality imaging, a form of non-linear optimization where the imaging configuration is automatically adjusted in response to the object. Preliminary studies suggest that substantial improvement in objective, task-based measures of image quality can result. We describe here our work to add motorized adjustment capabilities and a matching CT to our existing FastSPECT II system to form an adaptive small-animal SPECT/CT. PMID:26617457

  13. 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.

    PubMed

    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.

  14. Small-animal SPECT and SPECT/CT: application in cardiovascular research

    PubMed Central

    Golestani, Reza; Wu, Chao; Tio, René A.; Zeebregts, Clark J.; Petrov, Artiom D.; Beekman, Freek J.; Dierckx, Rudi A. J. O.; Slart, Riemer H. J. A.

    2010-01-01

    Preclinical cardiovascular research using noninvasive radionuclide and hybrid imaging systems has been extensively developed in recent years. Single photon emission computed tomography (SPECT) is based on the molecular tracer principle and is an established tool in noninvasive imaging. SPECT uses gamma cameras and collimators to form projection data that are used to estimate (dynamic) 3-D tracer distributions in vivo. Recent developments in multipinhole collimation and advanced image reconstruction have led to sub-millimetre and sub-half-millimetre resolution SPECT in rats and mice, respectively. In this article we review applications of microSPECT in cardiovascular research in which information about the function and pathology of the myocardium, vessels and neurons is obtained. We give examples on how diagnostic tracers, new therapeutic interventions, pre- and postcardiovascular event prognosis, and functional and pathophysiological heart conditions can be explored by microSPECT, using small-animal models of cardiovascular disease. PMID:20069298

  15. Microdialysis and SPECT measurements of amphetamine-induced dopamine release in nonhuman primates.

    PubMed

    Laruelle, M; Iyer, R N; al-Tikriti, M S; Zea-Ponce, Y; Malison, R; Zoghbi, S S; Baldwin, R M; Kung, H F; Charney, D S; Hoffer, P B; Innis, R B; Bradberry, C W

    1997-01-01

    The competition between endogenous transmitters and radiolabeled ligands for in vivo binding to neuroreceptors might provide a method to measure endogenous transmitter release in the living human brain with noninvasive techniques such as positron emission tomography (PET) or single photon emission computerized tomography (SPECT). In this study, we validated the measure of amphetamine-induced dopamine release with SPECT in nonhuman primates. Microdialysis experiments were conducted to establish the dose-response curve of amphetamine-induced dopamine release and to document how pretreatment with the dopamine depleter alpha-methyl-para-tyrosine (alpha MPT) affects this response. SPECT experiments were performed with two iodinated benzamides, [123I]IBZM and [123I]IBF, under sustained equilibrium condition. Both radio-tracers are specific D2 antagonists, but the affinity of [123I]IBZM (KD-0.4 nM) is lower than that of [123I]IBF (KD 0.1 nM). With both tracers, we observed a prolonged reduction in binding to D2 receptors following amphetamine injection. [123I]IBZM binding to D2 receptors was more affected than [123I]IBF by high doses of amphetamine, indicating that a lower affinity increases the vulnerability of a tracer to endogenous competition. With [123I]IBZM, we observed an excellent correlation between reduction of D2 receptor binding measured with SPECT and peak dopamine release measured with microdialysis after various doses of amphetamine. Pretreatment with alpha MPT significantly reduced the effect of amphetamine on [123I]IBZM binding to D2 receptors, confirming that this effect was mediated by intrasynaptic dopamine release. Together, these results validate the use of this SPECT paradigm as a noninvasive measurement of intrasynaptic dopamine release in the living brain.

  16. Development of [(123)I]IPEB and [(123)I]IMPEB as SPECT Radioligands for Metabotropic Glutamate Receptor Subtype 5.

    PubMed

    Kil, Kun-Eek; Zhu, Aijun; Zhang, Zhaoda; Choi, Ji-Kyung; Kura, Sreekanth; Gong, Chunyu; Brownell, Anna-Liisa

    2014-06-12

    mGlu5 play an important role in physiology and pathology to various central nervous system (CNS) diseases. Several positron emission tomography (PET) radiotracers have been developed to explore the role of mGlu5 in brain disorders. However, there are no single photon emission computed tomography (SPECT) radioligands for mGlu5. Here we report development of [(123)I]IPEB ([(123)I]1) and [(123)I]IMPEB ([(123)I]2) as mGlu5 radioligands for SPECT. [(123)I]1 and [(123)I]2 were produced by copper(I) mediated aromatic halide displacement reactions. The SPECT imaging using mouse models demonstrated that [(123)I]1 readily entered the brain and accumulated specifically in mGlu5-rich regions of the brain such as striatum and hippocampus. However, in comparison to the corresponding PET tracer [(18)F]FPEB, [(123)I]1 showed faster washout from the brain. The binding ratios of the striatum and the hippocampus compared to the cerebellum for [(123)I]1 and [(18)F]FPEB were similar despite unfavorable pharmacokinetics of [(123)I]1. Further structural optimization of 1 may lead to more viable SPECT radiotracers for the imaging of mGlu5.

  17. SPECT, MRI and cognitive functions in multiple sclerosis.

    PubMed Central

    Pozzilli, C; Passafiume, D; Bernardi, S; Pantano, P; Incoccia, C; Bastianello, S; Bozzao, L; Lenzi, G L; Fieschi, C

    1991-01-01

    Seventeen patients with relapsing remitting multiple sclerosis (MS) and mild physical disability had neuropsychological testing, magnetic resonance imaging (MRI) and single photon emission computerised tomography (SPECT) using technetium 99m (99mTc) hexamethyl-propyleneamine oxime (HMPAO). Performance in verbal fluency, naming and memory testing appeared to be impaired in MS patients compared with 17 age-sex and education matched normal controls. Weighted periventricular and confluent lesion scores and the width of the third ventricle, proved to be the most sensitive MRI measures in differentiating more cognitively impaired patients from those who were relatively unimpaired. Ratios of regional to whole brain activity, measured by SPECT, showed significant reduction in the frontal lobes and in the left temporal lobe of MS patients. A relationship was found between left temporal abnormality in 99mTc-HMPAO uptake and deficit in verbal fluency and verbal memory. Finally, asymmetrical lobar activity indicated a predominant left rather than right temporo-parietal involvement. PMID:2019835

  18. Development of PET and SPECT Probes for Glutamate Receptors

    PubMed Central

    Nakayama, Morio

    2015-01-01

    l-Glutamate and its receptors (GluRs) play a key role in excitatory neurotransmission within the mammalian central nervous system (CNS). Impaired regulation of GluRs has also been implicated in various neurological disorders. GluRs are classified into two major groups: ionotropic GluRs (iGluRs), which are ligand-gated ion channels, and metabotropic GluRs (mGluRs), which are coupled to heterotrimeric guanosine nucleotide binding proteins (G-proteins). Positron emission tomography (PET) and single photon emission computed tomography (SPECT) imaging of GluRs could provide a novel view of CNS function and of a range of brain disorders, potentially leading to the development of new drug therapies. Although no satisfactory imaging agents have yet been developed for iGluRs, several PET ligands for mGluRs have been successfully employed in clinical studies. This paper reviews current progress towards the development of PET and SPECT probes for GluRs. PMID:25874256

  19. Intrinsic Feature Pose Measurement for Awake Animal SPECT Imaging

    SciTech Connect

    Goddard Jr, James Samuel; Baba, Justin S; Lee, Seung Joon; Weisenberger, A G; Stolin, A; McKisson, J; Smith, M F

    2009-01-01

    New developments have been made in optical motion tracking for awake animal imaging that measures 3D position and orientation (pose) for a single photon emission computed tomography (SPECT) imaging system. Ongoing SPECT imaging research has been directed towards head motion measurement for brain studies in awake, unrestrained mice. In contrast to previous results using external markers, this work extracts and tracks intrinsic features from multiple camera images and computes relative pose from the tracked features over time. Motion tracking thus far has been limited to measuring extrinsic features such as retro-reflective markers applied to the mouse s head. While this approach has been proven to be accurate, the additional animal handling required to attach the markers is undesirable. A significant improvement in the procedure is achieved by measuring the pose of the head without extrinsic markers using only the external surface appearance. This approach is currently being developed with initial results presented here. The intrinsic features measurement extracts discrete, sparse natural features from 2D images such as eyes, nose, mouth and other visible structures. Stereo correspondence between features for a camera pair is determined for calculation of 3D positions. These features are also tracked over time to provide continuity for surface model fitting. Experimental results from live images are presented.

  20. Monitoring CBF in clinical routine by dynamic single photon emission tomography (SPECT) of inhaled xenon-133

    SciTech Connect

    Sugiyama, H.; Christensen, J.; Skyhoj Olsen, T.; Lassen, N.A.

    1986-11-01

    A very simple and low-cost brain dedicated, rapidly rotating Single Photon Emission Tomograph SPECT is described. Its use in following patients with ischemic stroke is illustrated by two middle cerebral artery occlusion cases, one with persistent occlusion and low CBF in MCA territory, and one with early lysis of the occlusion having high CBF (massive luxury perfusion) for some weeks. Evidence of this kind may be essential in the evaluation of therapeutic measures in ischemic stroke.

  1. Imaging analysis of Parkinson’s disease patients using SPECT and tractography

    PubMed Central

    Son, Seong-Jin; Kim, Mansu; Park, Hyunjin

    2016-01-01

    Parkinson’s disease (PD) is a degenerative disorder that affects the central nervous system. PD-related alterations in structural and functional neuroimaging have not been fully explored. This study explored multi-modal PD neuroimaging and its application for predicting clinical scores on the Movement Disorder Society-sponsored Unified Parkinson’s Disease Rating Scale (MDS-UPDRS). Multi-modal imaging that combined 123I-Ioflupane single-photon emission computed tomography (SPECT) and diffusion tensor imaging (DTI) were adopted to incorporate complementary brain imaging information. SPECT and DTI images of normal controls (NC; n = 45) and PD patients (n = 45) were obtained from a database. The specific binding ratio (SBR) was calculated from SPECT. Tractography was performed using DTI. Group-wise differences between NC and PD patients were quantified using SBR of SPECT and structural connectivity of DTI for regions of interest (ROIs) related to PD. MDS-UPDRS scores were predicted using multi-modal imaging features in a partial least-squares regression framework. Three regions and four connections within the cortico-basal ganglia thalamocortical circuit were identified using SBR and DTI, respectively. Predicted MDS-UPDRS scores using identified regions and connections and actual MDS-UPDRS scores showed a meaningful correlation (r = 0.6854, p < 0.001). Our study provided insight on regions and connections that are instrumental in PD. PMID:27901100

  2. Multimodal imaging with hybrid semiconductor detectors Timepix for an experimental MRI-SPECT system

    NASA Astrophysics Data System (ADS)

    Zajicek, J.; Jakubek, J.; Burian, M.; Vobecky, M.; Fauler, A.; Fiederle, M.; Zwerger, A.

    2013-01-01

    An increasing number of clinical applications are being based on multimodal imaging systems (MIS), including anatomical (CT, MRI) and functional (PET, SPECT) techniques to provide complex information in a single image. CT with one of the scintigraphic methods (PET or SPECT) is nowadays a combination of choice for clinical practice and it is mostly used in cardiography and tumour diagnostics. Combination with MRI is also being implemented as no radiation dose is imparted to the patient and it is possible to gain higher structural resolution of soft tissues (brain imaging). A major disadvantage of such systems is inability to operate scintillators with photomultipliers (used for detection of γ rays) in presence of high magnetic fields. In this work we present the application of the semiconductor pixel detector for SPECT method in combination with MR imaging. We propose a novel approach based on MRI compatible setup with CdTe pixel sensor Timepix and non-conductive collimator. Measurements were performed on high proton-density (PD) phantom (1H) with an embedded radioisotopic source inside the shielded RF coil by MRI animal scanner (4.7 T). Our results pave the way for a combined MRI-SPECT system. The project was performed in the framework of the Medipix Collaboration.

  3. Improving the count rate performance of a modular cylindrical SPECT system

    SciTech Connect

    Li, Y.J.; Hollinger, E.F.; Liu, J.; Chang, W.

    1996-12-31

    We recently proposed a design of a modular cylindrical cardiac SPECT system. one special feature of this system is an integrated provision for transmission imaging. To meet the clinical demands of obtaining transmission images, this system must be able to achieve a very high count rate (CR). To explore methods for achieving a high CR capability on a modular cylindrical detector system, we have used our existing modular cylindrical brain SPECT system to examine the feasibility of two approaches. First, we use digital-signal-processing (DSP) boards, in parallel, to execute real time position calculations. Second, we use local encoding and triggering circuits to perform analog signal processing, including identifying the detector module and digitizing the pulse signals. The results of our preliminary investigations indicate that applying the multiple-DSP parallel position calculation and local triggering techniques in a modular SPECT system can improve the CR capability significantly. Applying local triggering increased the CR capability by 15% at a CR capability of 200 kcps. Because we have used slow-speed DSP boards during this proof-of-concept testing, we have not yet met the CR requirements for transmission imaging. However, these results indicate that by using state-of-the-art DSP boards the CR capability of this modular SPECT system can be increased to over 300 kcps.

  4. A practical correction of scatter-related artifacts in SPECT reconstruction

    NASA Astrophysics Data System (ADS)

    Ye, Hongwei; Krol, Andrzej; Lipson, Edward D.; Kunniyur, Vikram R.; Lee, Wei; Feiglin, David H.

    2007-03-01

    We have observed that an expectation maximization (EM) algorithm applied to SPECT reconstruction may produce hotspot artifacts of varying intensity. Our hypothesis was that scatter caused these artifacts. To test this assumption, we studied the performance of forward- and back-projection procedures in the EM algorithm for simulated and experimental SPECT data. First, synthetic scatter-free projections and projections with only one scattered photon in each view were created for a simulated simple object, and reconstructed with a fully 3D ordered-subsets EM (OSEM) algorithm. Then, Monte Carlo simulated brain SPECT (with no scatter and with scatter present), a mini-Defrise phantom, and patient SPECT were reconstructed. We confirmed our hypothesis: hot-spot artifacts appeared only in the reconstruction from noisy projections but not in the reconstruction from scatter-free projections. We investigated a practical and simple method, critical path-length control (CPLC), for suppression of the hot-spot artifacts. To this end we performed reconstructions with or without CPLC and quantitatively evaluated the results including estimation of accuracy, bias, contrast-to-noise ratio, and uniformity. We found that the OSEM-with-CPLC method significantly reduced hot-spot artifacts, and yielded a similar or improved image quality. We conclude that the CPLC method provides a useful yet simple tool to reduce scatter-related hot-spot artifacts.

  5. 123I-IMP-SPECT in a patient with cerebral proliferative angiopathy: a case report.

    PubMed

    Kimiwada, Tomomi; Hayashi, Toshiaki; Shirane, Reizo; Tominaga, Teiji

    2013-11-01

    Cerebral proliferative angiopathy (CPA) is a new clinical entity demonstrating a diffuse network of densely enhanced vascular abnormalities with intermingled normal brain parenchyma and is distinguishable from classical arteriovenous malformations by specific clinical and imaging markers. However, the pathophysiological nature of this disease is unclear, and there is no consensus on the treatment. We describe cerebral perfusion abnormalities in a patient with CPA by using N-isopropyl-p-[123I] iodoamphetamine single-photon emission computed tomography (123I-IMP-SPECT) and perfusion-weighted magnetic resonance imaging. The patient, a 13-year-old boy, had reversible focal neurological deficits unrelated to cerebral hemorrhage. 123I-IMP-SPECT at resting state showed preserved uptake within the vascular lesion, yet lower uptake in the area adjacent to the lesion. In addition, acetazolamide-stressed 123I-IMP-SPECT exhibited severely impaired cerebrovascular reactivity over the affected hemisphere, suggesting that his focal neurological deficits were related to the cerebral ischemia. The perfusion abnormalities on 123I-IMP-SPECT in a CPA patient have never been previously reported. The concept of vascular malformation-related hypoperfusion is discussed. Copyright © 2013 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  6. Quantitative Monte Carlo-based holmium-166 SPECT reconstruction.

    PubMed

    Elschot, Mattijs; Smits, Maarten L J; Nijsen, Johannes F W; Lam, Marnix G E H; Zonnenberg, Bernard A; van den Bosch, Maurice A A J; Viergever, Max A; de Jong, Hugo W A M

    2013-11-01

    Quantitative imaging of the radionuclide distribution is of increasing interest for microsphere radioembolization (RE) of liver malignancies, to aid treatment planning and dosimetry. For this purpose, holmium-166 ((166)Ho) microspheres have been developed, which can be visualized with a gamma camera. The objective of this work is to develop and evaluate a new reconstruction method for quantitative (166)Ho SPECT, including Monte Carlo-based modeling of photon contributions from the full energy spectrum. A fast Monte Carlo (MC) simulator was developed for simulation of (166)Ho projection images and incorporated in a statistical reconstruction algorithm (SPECT-fMC). Photon scatter and attenuation for all photons sampled from the full (166)Ho energy spectrum were modeled during reconstruction by Monte Carlo simulations. The energy- and distance-dependent collimator-detector response was modeled using precalculated convolution kernels. Phantom experiments were performed to quantitatively evaluate image contrast, image noise, count errors, and activity recovery coefficients (ARCs) of SPECT-fMC in comparison with those of an energy window-based method for correction of down-scattered high-energy photons (SPECT-DSW) and a previously presented hybrid method that combines MC simulation of photopeak scatter with energy window-based estimation of down-scattered high-energy contributions (SPECT-ppMC+DSW). Additionally, the impact of SPECT-fMC on whole-body recovered activities (A(est)) and estimated radiation absorbed doses was evaluated using clinical SPECT data of six (166)Ho RE patients. At the same noise level, SPECT-fMC images showed substantially higher contrast than SPECT-DSW and SPECT-ppMC+DSW in spheres ≥ 17 mm in diameter. The count error was reduced from 29% (SPECT-DSW) and 25% (SPECT-ppMC+DSW) to 12% (SPECT-fMC). ARCs in five spherical volumes of 1.96-106.21 ml were improved from 32%-63% (SPECT-DSW) and 50%-80% (SPECT-ppMC+DSW) to 76%-103% (SPECT-fMC). Furthermore

  7. Latent profile analysis in frontotemporal lobar degeneration and related disorders: clinical presentation and SPECT functional correlates

    PubMed Central

    Borroni, Barbara; Grassi, Mario; Agosti, Chiara; Paghera, Barbara; Alberici, Antonella; Di Luca, Monica; Perani, Daniela; Padovani, Alessandro

    2007-01-01

    Background Frontotemporal Lobar Degeneration (FTLD) thus recently renamed, refers to a spectrum of heterogeneous conditions. This same heterogeneity of presentation represents the major methodological limit for the correct evaluation of clinical designation and brain functional correlates. At present, no study has investigated clinical clusters due to specific cognitive and behavioural disturbances beyond current clinical criteria. The aim of this study was to identify clinical FTLD presentation, based on cognitive and behavioural profile, and to define their SPECT functional correlations. Methods Ninety-seven FTLD patients entered the study. A clinical evaluation and standardised assessment were preformed, as well as a brain SPECT perfusion imaging study. Latent Profile Analysis on clinical, neuropsychological, and behavioural data was performed. Voxel-basis analysis of SPECT data was computed. Results Three specific clusters were identified and named "pseudomanic behaviour" (LC1), "cognitive" (LC2), and "pseudodepressed behaviour" (LC3) endophenotypes. These endophenotypes showed a comparable hypoperfusion in left temporal lobe, but a specific pattern involving: medial and orbitobasal frontal cortex in LC1, subcortical brain region in LC2, and right dorsolateral frontal cortex and insula in LC3. Conclusion These findings provide evidence that specific functional-cluster symptom relationship can be delineated in FTLD patients by a standardised assessment. The understanding of the different functional correlates of clinical presentations will hopefully lead to the possibility of individuating diagnostic and treatment algorithms. PMID:17506892

  8. N-allyl epiderpride: An extremely potent SPECT radioligand for the dopamine D2 receptor

    SciTech Connect

    Kessler, R.M.; Mason, N.S.; Ansari, M.S.

    1994-05-01

    We have previously reported that epidepride is a potent (K{sub D} 24pM) and specific SPECT radioligand for the dopamine D2 receptor which can be used to study striatal and extrastriatal dopamine D2 receptors in man. We have synthesized and evaluated the N-allyl analogue of epiderpride (APID) as a potential SPECT radioligand for the dopamine D2 receptor. In comparison to epidepride it is even more potent at the dopamine D2 receptor, the K{sub D} for APID being 11 frontal cortical homogenate. The lipophilicity, evaluated using the log kw pH 7.5, was 2.9 versus 2.05 for epidepride. Competitive binding studies using rat striatal, hippocampal and frontal cortical homogenates showed high affinity for only dopamine D2 like cerebellar ratio of 275:1 at 320 minutes post injection-similar to that seen with epidepride, but with nearly four times higher brain uptake. Of interest was the off-rate from the dopamine D2 receptor; it was 0.0046 min{sup -1} in vitro at 25{degrees}C-corresponding to an t 1/2 of 150 minutes. Studies in rhesus monkeys show an in vivo off rate (following 2.5 mg/kg raclopride IV) of about 0.0082 min{sup -1} seen that with epidepride. SPECT studies in rhesus monkeys reveal APID is a promising SPECT radioligand that appears to be similar to epidepride, but with higher brain uptake due to its more optimal lipophilicity for entry into brain.

  9. Multi-pinhole collimator design for small-object imaging with SiliSPECT: a high-resolution SPECT

    PubMed Central

    Shokouhi, S; Metzler, S D; Wilson, D W; Peterson, T E

    2010-01-01

    We have designed a multi-pinhole collimator for a dual-headed, stationary SPECT system that incorporates high-resolution silicon double-sided strip detectors. The compact camera design of our system enables imaging at source–collimator distances between 20 and 30 mm. Our analytical calculations show that using knife-edge pinholes with small-opening angles or cylindrically shaped pinholes in a focused, multi-pinhole configuration in combination with this camera geometry can generate narrow sensitivity profiles across the field of view that can be useful for imaging small objects at high sensitivity and resolution. The current prototype system uses two collimators each containing 127 cylindrically shaped pinholes that are focused toward a target volume. Our goal is imaging objects such as a mouse brain, which could find potential applications in molecular imaging. PMID:19088387

  10. Characterisation of radioiodinated flavonoid derivatives for SPECT imaging of cerebral prion deposits

    PubMed Central

    Fuchigami, Takeshi; Yamashita, Yuki; Kawasaki, Masao; Ogawa, Ayaka; Haratake, Mamoru; Atarashi, Ryuichiro; Sano, Kazunori; Nakagaki, Takehiro; Ubagai, Kaori; Ono, Masahiro; Yoshida, Sakura; Nishida, Noriyuki; Nakayama, Morio

    2015-01-01

    Prion diseases are fatal neurodegenerative diseases characterised by deposition of amyloid plaques containing abnormal prion protein aggregates (PrPSc). This study aimed to evaluate the potential of radioiodinated flavonoid derivatives for single photon emission computed tomography (SPECT) imaging of PrPSc. In vitro binding assays using recombinant mouse PrP (rMoPrP) aggregates revealed that the 4-dimethylamino-substituted styrylchromone derivative (SC-NMe2) had higher in vitro binding affinity (Kd = 24.5 nM) and capacity (Bmax = 36.3 pmol/nmol protein) than three other flavonoid derivatives (flavone, chalcone, and aurone). Fluorescent imaging using brain sections from mouse-adapted bovine spongiform encephalopathy (mBSE)-infected mice demonstrated that SC-NMe2 clearly labelled PrPSc-positive prion deposits in the mice brain. Two methoxy SC derivatives, SC-OMe and SC-(OMe)2, also showed high binding affinity for rMoPrP aggregates with Ki values of 20.8 and 26.6 nM, respectively. In vitro fluorescence and autoradiography experiments demonstrated high accumulation of [125I]SC-OMe and [125I]SC-(OMe)2 in prion deposit-rich regions of the mBSE-infected mouse brain. SPECT/computed tomography (CT) imaging and ex vivo autoradiography demonstrated that [123I]SC-OMe showed consistent brain distribution with the presence of PrPSc deposits in the mBSE-infected mice brain. In conclusion, [123I]SC-OMe appears a promising SPECT radioligand for monitoring prion deposit levels in the living brain. PMID:26669576

  11. Characterisation of radioiodinated flavonoid derivatives for SPECT imaging of cerebral prion deposits.

    PubMed

    Fuchigami, Takeshi; Yamashita, Yuki; Kawasaki, Masao; Ogawa, Ayaka; Haratake, Mamoru; Atarashi, Ryuichiro; Sano, Kazunori; Nakagaki, Takehiro; Ubagai, Kaori; Ono, Masahiro; Yoshida, Sakura; Nishida, Noriyuki; Nakayama, Morio

    2015-12-16

    Prion diseases are fatal neurodegenerative diseases characterised by deposition of amyloid plaques containing abnormal prion protein aggregates (PrP(Sc)). This study aimed to evaluate the potential of radioiodinated flavonoid derivatives for single photon emission computed tomography (SPECT) imaging of PrP(Sc). In vitro binding assays using recombinant mouse PrP (rMoPrP) aggregates revealed that the 4-dimethylamino-substituted styrylchromone derivative (SC-NMe2) had higher in vitro binding affinity (Kd = 24.5 nM) and capacity (Bmax = 36.3 pmol/nmol protein) than three other flavonoid derivatives (flavone, chalcone, and aurone). Fluorescent imaging using brain sections from mouse-adapted bovine spongiform encephalopathy (mBSE)-infected mice demonstrated that SC-NMe2 clearly labelled PrP(Sc)-positive prion deposits in the mice brain. Two methoxy SC derivatives, SC-OMe and SC-(OMe)2, also showed high binding affinity for rMoPrP aggregates with Ki values of 20.8 and 26.6 nM, respectively. In vitro fluorescence and autoradiography experiments demonstrated high accumulation of [(125)I]SC-OMe and [(125)I]SC-(OMe)2 in prion deposit-rich regions of the mBSE-infected mouse brain. SPECT/computed tomography (CT) imaging and ex vivo autoradiography demonstrated that [(123)I]SC-OMe showed consistent brain distribution with the presence of PrP(Sc) deposits in the mBSE-infected mice brain. In conclusion, [(123)I]SC-OMe appears a promising SPECT radioligand for monitoring prion deposit levels in the living brain.

  12. Development of novel 123I-labeled pyridyl benzofuran derivatives for SPECT imaging of β-amyloid plaques in Alzheimer's disease.

    PubMed

    Ono, Masahiro; Cheng, Yan; Kimura, Hiroyuki; Watanabe, Hiroyuki; Matsumura, Kenji; Yoshimura, Masashi; Iikuni, Shimpei; Okamoto, Yoko; Ihara, Masafumi; Takahashi, Ryosuke; Saji, Hideo

    2013-01-01

    Imaging of β-amyloid (Aβ) plaques in the brain may facilitate the diagnosis of cerebral β-amyloidosis, risk prediction of Alzheimer's disease (AD), and effectiveness of anti-amyloid therapies. The purpose of this study was to evaluate novel (123)I-labeled pyridyl benzofuran derivatives as SPECT probes for Aβ imaging. The formation of a pyridyl benzofuran backbone was accomplished by Suzuki coupling. [(123)I/(125)I]-labeled pyridyl benzofuran derivatives were readily prepared by an iododestannylation reaction. In vitro Aβ binding assays were carried out using Aβ(1-42) aggregates and postmortem human brain sections. Biodistribution experiments were conducted in normal mice at 2, 10, 30, and 60 min postinjection. Aβ labeling in vivo was evaluated by small-animal SPECT/CT in Tg2576 transgenic mice injected with [(123)I]8. Ex vivo autoradiography of the brain sections was performed after SPECT/CT. Iodinated pyridyl benzofuran derivatives showed excellent affinity for Aβ(1-42) aggregates (2.4 to 10.3 nM) and intensely labeled Aβ plaques in autoradiographs of postmortem AD brain sections. In biodistribution experiments using normal mice, all these derivatives displayed high initial uptake (4.03-5.49% ID/g at 10 min). [(125)I]8 displayed the quickest clearance from the brain (1.30% ID/g at 60 min). SPECT/CT with [(123)I]8 revealed higher uptake of radioactivity in the Tg2576 mouse brain than the wild-type mouse brain. Ex vivo autoradiography showed in vivo binding of [(123)I]8 to Aβ plaques in the Tg2576 mouse brain. These combined results warrant further investigation of [(123)I]8 as a SPECT imaging agent for visualizing Aβ plaques in the AD brain.

  13. Performance evaluation of D-SPECT: a novel SPECT system for nuclear cardiology

    NASA Astrophysics Data System (ADS)

    Erlandsson, Kjell; Kacperski, Krzysztof; van Gramberg, Dean; Hutton, Brian F.

    2009-05-01

    D-SPECT (Spectrum Dynamics, Israel) is a novel SPECT system for cardiac perfusion studies. Based on CZT detectors, region-centric scanning, high-sensitivity collimators and resolution recovery, it offers potential advantages over conventional systems. A series of measurements were made on a β-version D-SPECT system in order to evaluate its performance in terms of energy resolution, scatter fraction, sensitivity, count rate capability and resolution. Corresponding measurements were also done on a conventional SPECT system (CS) for comparison. The energy resolution of the D-SPECT system at 140 keV was 5.5% (CS: 9.25%), the scatter fraction 30% (CS: 34%), the planar sensitivity 398 s-1 MBq-1 per head (99mTc, 10 cm) (CS: 72 s-1 MBq-1), and the tomographic sensitivity in the heart region was in the range 647-1107 s-1 MBq-1 (CS: 141 s-1 MBq-1). The count rate increased linearly with increasing activity up to 1.44 M s-1. The intrinsic resolution was equal to the pixel size, 2.46 mm (CS: 3.8 mm). The average reconstructed resolution using the standard clinical filter was 12.5 mm (CS: 13.7 mm). The D-SPECT has superior sensitivity to that of a conventional system with similar spatial resolution. It also has excellent energy resolution and count rate characteristics, which should prove useful in dynamic and dual radionuclide studies.

  14. Performance evaluation of D-SPECT: a novel SPECT system for nuclear cardiology.

    PubMed

    Erlandsson, Kjell; Kacperski, Krzysztof; van Gramberg, Dean; Hutton, Brian F

    2009-05-07

    D-SPECT (Spectrum Dynamics, Israel) is a novel SPECT system for cardiac perfusion studies. Based on CZT detectors, region-centric scanning, high-sensitivity collimators and resolution recovery, it offers potential advantages over conventional systems. A series of measurements were made on a beta-version D-SPECT system in order to evaluate its performance in terms of energy resolution, scatter fraction, sensitivity, count rate capability and resolution. Corresponding measurements were also done on a conventional SPECT system (CS) for comparison. The energy resolution of the D-SPECT system at 140 keV was 5.5% (CS: 9.25%), the scatter fraction 30% (CS: 34%), the planar sensitivity 398 s(-1) MBq(-1) per head ((99m)Tc, 10 cm) (CS: 72 s(-1) MBq(-1)), and the tomographic sensitivity in the heart region was in the range 647-1107 s(-1) MBq(-1) (CS: 141 s(-1) MBq(-1)). The count rate increased linearly with increasing activity up to 1.44 M s(-1). The intrinsic resolution was equal to the pixel size, 2.46 mm (CS: 3.8 mm). The average reconstructed resolution using the standard clinical filter was 12.5 mm (CS: 13.7 mm). The D-SPECT has superior sensitivity to that of a conventional system with similar spatial resolution. It also has excellent energy resolution and count rate characteristics, which should prove useful in dynamic and dual radionuclide studies.

  15. Freehand SPECT in low uptake situations

    NASA Astrophysics Data System (ADS)

    Lasser, Tobias; Ziegler, Sibylle I.; Navab, Nassir

    2011-03-01

    3D functional imaging in the operating room can be extremely useful for some procedures like SLN mapping or SLN biopsies. Freehand SPECT is an example of such an imaging modality, combining manually scanned, hand-held 1D gamma detectors with spatial positioning systems in order to reconstruct localized 3D SPECT images, for example in the breast or neck region. Standard series expansion methods are applied together with custom physical models of the acquisition process and custom filtering procedures to perform 3D tomographic reconstruction from sparse, limited-angle and irregularly sampled data. A Freehand SPECT system can easily be assembled on a mobile cart suitable for use in the operating room. This work addresses in particular the problem of objects with low uptake (like sentinel lymph nodes), where reconstruction tends to be difficult due to low signal to noise ratio. In a neck-like phantom study, we show that four simulated nodes of 250 microliter volume with 0.06% respectively 0.03% uptake of a virtual 70MBq injection of Tc99m (the typical activity for SLN procedures at our hospital) in a background of water can be reconstructed successfully using careful filtering procedures in the reconstruction pipeline. Ten independent Freehand SPECT scans of the phantom were performed by several different operators, with an average scan duration of 5.1 minutes. The resulting reconstructions show an average spatial accuracy within voxel dimensions (2.5mm) compared to CT and exhibit correct relative quantification.

  16. SPECT gallium imaging in abdominal lymphoma

    SciTech Connect

    Adcock, K.A.; Friefeld, G.D.; Waldron, J.A. Jr.

    1986-05-01

    A case of non-Hodgkin's lymphoma of the abdomen studied by gallium SPECT imaging is reported. The tomographic slices accurately demonstrated the location of residual disease after chemotherapy in the region of the transverse mesocolon. Previous transmission CT had shown considerable persistent retroperitoneal lymphadenopathy, but was not helpful in determining the presence of viable lymphoma.

  17. Towards personalized interventional SPECT-CT imaging.

    PubMed

    Gardiazabal, José; Esposito, Marco; Matthies, Philipp; Okur, Asli; Vogel, Jakob; Kraft, Silvan; Frisch, Benjamin; Lasser, Tobias; Navab, Nassir

    2014-01-01

    The development of modern robotics and compact imaging detectors allows the transfer of diagnostic imaging modalities to the operating room, supporting surgeons to perform faster and safer procedures. An intervention that currently suffers from a lack of interventional imaging is radioembolization, a treatment for hepatic carcinoma. Currently, this procedure requires moving the patient from an angiography suite for preliminary catheterization and injection to a whole-body SPECT/CT for leakage detection, necessitating a second catheterization back in the angiography suite for the actual radioembolization. We propose an imaging setup that simplifies this procedure using a robotic approach to directly acquire an interventional SPECT/CT in the angiography suite. Using C-arm CT and a co-calibrated gamma camera mounted on a robotic arm, a personalized trajectory of the gamma camera is generated from the C-arm CT, enabling an interventional SPECT reconstruction that is inherently co-registered to the C-arm CT. In this work we demonstrate the feasibility of this personalized interventional SPECT/CT imaging approach in a liver phantom study.

  18. PET/SPECT molecular imaging in clinical neuroscience: recent advances in the investigation of CNS diseases

    PubMed Central

    Lu, Feng-Mei

    2015-01-01

    Molecular imaging is an attractive technology widely used in clinical practice that greatly enhances our understanding of the pathophysiology and treatment in central nervous system (CNS) diseases. It is a novel multidisciplinary technique that can be defined as real-time visualization, in vivo characterization and qualification of biological processes at the molecular and cellular level. It involves the imaging modalities and the corresponding imaging agents. Nowadays, molecular imaging in neuroscience has provided tremendous insights into disturbed human brain function. Among all of the molecular imaging modalities, positron emission tomography (PET) and single photon emission computed tomography (SPECT) have occupied a particular position that visualize and measure the physiological processes using high-affinity and high-specificity molecular radioactive tracers as imaging probes in intact living brain. In this review, we will put emphasis on the PET/SPECT applications in Alzheimer’s disease (AD) and Parkinson’s disease (PD) as major CNS disorders. We will first give an overview of the main classical molecular neuroimaging modalities. Then, the major clinical applications of PET and SPECT along with molecular probes in the fields of psychiatry and neurology will be discussed. PMID:26029646

  19. Generating Dynamic System Matrices for Dynamic SPECT

    SciTech Connect

    2011-02-01

    The purpose of the computer program is to generate system matrices that model data acquisition process in dynamic single photon emission computed tomography (SPECT). The application is for the reconstruction of dynamic data from projection measurements that provide the time evolution of activity uptake and wash out in an organ of interest. The measurement of the time activity in the blood and organ tissue provide time-activity curves (TACs) that are used to estimate kinetic parameters. The program provides a correct model of the in vivo spatial and temporal distribution of radioactive in organs. The model accounts for the attenuation of the internal emitting radioactivity, it accounts for the vary point response of the collimators, and correctly models the time variation of the activity in the organs. One important application where the software is being used in a measuring the arterial input function (AIF) in a dynamic SPECT study where the data are acquired from a slow camera rotation. Measurement of the arterial input function (AIF) is essential to deriving quantitative estimates of regional myocardial blood flow using kinetic models. A study was performed to evaluate whether a slowly rotating SPECT system could provide accurate AIF's for myocardial perfusion imaging (MPI). Methods: Dynamic cardiac SPECT was first performed in human subjects at rest using a Phillips Precedence SPECT/CT scanner. Dynamic measurements of Tc-99m-tetrofosmin in the myocardium were obtained using an infusion time of 2 minutes. Blood input, myocardium tissue and liver TACs were estimated using spatiotemporal splines. These were fit to a one-compartment perfusion model to obtain wash-in rate parameters K1. Results: The spatiotemporal 4D ML-EM reconstructions gave more accurate reconstructions that did standard frame-by-frame 3D ML-EM reconstructions. From additional computer simulations and phantom studies, it was determined that a 1 minute infusion with a SPECT system rotation speed

  20. Unlocking the Secrets of the Brain, Part II: A Continuing Look at Techniques for Exploring the Brain.

    ERIC Educational Resources Information Center

    Powledge, Tabitha M.

    1997-01-01

    Describes techniques for delving into the brain including positron emission tomography (PET), single photon emission computed tomography (SPECT), electroencephalogram (EEG), magnetoencephalography (MEG), transcranial magnetic stimulation (TMS), and low-tech indirect studies. (JRH)

  1. Unlocking the Secrets of the Brain, Part II: A Continuing Look at Techniques for Exploring the Brain.

    ERIC Educational Resources Information Center

    Powledge, Tabitha M.

    1997-01-01

    Describes techniques for delving into the brain including positron emission tomography (PET), single photon emission computed tomography (SPECT), electroencephalogram (EEG), magnetoencephalography (MEG), transcranial magnetic stimulation (TMS), and low-tech indirect studies. (JRH)

  2. Monte Carlo scatter correction for SPECT

    NASA Astrophysics Data System (ADS)

    Liu, Zemei

    The goal of this dissertation is to present a quantitatively accurate and computationally fast scatter correction method that is robust and easily accessible for routine applications in SPECT imaging. A Monte Carlo based scatter estimation method is investigated and developed further. The Monte Carlo simulation program SIMIND (Simulating Medical Imaging Nuclear Detectors), was specifically developed to simulate clinical SPECT systems. The SIMIND scatter estimation (SSE) method was developed further using a multithreading technique to distribute the scatter estimation task across multiple threads running concurrently on multi-core CPU's to accelerate the scatter estimation process. An analytical collimator that ensures less noise was used during SSE. The research includes the addition to SIMIND of charge transport modeling in cadmium zinc telluride (CZT) detectors. Phenomena associated with radiation-induced charge transport including charge trapping, charge diffusion, charge sharing between neighboring detector pixels, as well as uncertainties in the detection process are addressed. Experimental measurements and simulation studies were designed for scintillation crystal based SPECT and CZT based SPECT systems to verify and evaluate the expanded SSE method. Jaszczak Deluxe and Anthropomorphic Torso Phantoms (Data Spectrum Corporation, Hillsborough, NC, USA) were used for experimental measurements and digital versions of the same phantoms employed during simulations to mimic experimental acquisitions. This study design enabled easy comparison of experimental and simulated data. The results have consistently shown that the SSE method performed similarly or better than the triple energy window (TEW) and effective scatter source estimation (ESSE) methods for experiments on all the clinical SPECT systems. The SSE method is proven to be a viable method for scatter estimation for routine clinical use.

  3. Studying Spatial Resolution of CZT Detectors Using Sub-Pixel Positioning for SPECT

    NASA Astrophysics Data System (ADS)

    Montémont, Guillaume; Lux, Silvère; Monnet, Olivier; Stanchina, Sylvain; Verger, Loïck

    2014-10-01

    CZT detectors are the basic building block of a variety of new SPECT systems. Their modularity allows adapting system architecture to specific applications such as cardiac, breast, brain or small animal imaging. In semiconductors, a high number of electron-hole pairs is produced by a single interaction. This direct conversion process allows better energy and spatial resolutions than usual scintillation detectors based on NaI(Tl). However, it remains often unclear if SPECT imaging can really benefit of that performance gain. We investigate the system performance of a detection module, which is based on 5 mm thick CZT with a segmented anode having a 2.5 mm pitch by simulation and experimentation. This pitch allows an easy assembly of the crystal on the readout board and limits the space occupied by electronics without significantly degrading energy and spatial resolution.

  4. "Luxury perfusion" with 99mTc-HMPAO and 123I-IMP SPECT imaging during the subacute phase of stroke.

    PubMed

    Moretti, J L; Defer, G; Cinotti, L; Cesaro, P; Degos, J D; Vigneron, N; Ducassou, D; Holman, B L

    1990-01-01

    To compare the merits of 123I-isopropyl-iodoamphetamine (123I-IMP) and 99mTc-HMPAO in showing abnormal brain uptake distribution during cerebral ischemia, we studied ten patients during the subacute phase of their stroke, a period where metabolism and blood flow are frequently uncoupled. SPECT imaging was performed using both radiopharmaceuticals in the 10 patients from 48 h to 4 weeks after onset of symptoms. Two patients out of the 10 had similar defects with 123I-IMP and 99mTc-HMPAO SPECT, the location of the defects corresponding to the area of infarction observed on CT. Six patients had normal 99mTc-HMPAO SPECT and abnormal 123I-IMP SPECT with defects in the area of infarction shown by CT. The remaining 2 patients had hyperactive abnormalities on 99mTc-HMPAO in areas corresponding to defects on the 123I-IMP images. Two of the patients with SPECT mismatches were studied again more than 1 month after onset. On reexamination, 99mTc-HMPAO SPECT which was previously normal or hyperactive became hypoactive with a focal area of decreased activity corresponding to the defect on 123I-IMP. Crossed cerebellar diaschisis was found in 7 patients with 99mTc-HMPAO and was absent for both 123I-IMP and 99mTc-HMPAO in 3. We suggest that SPECT with 99mTc-HMPAO could show transient hyperemia not demonstrated by 123I-IMP whereas in some cases cerebral infarction would be more difficult to demonstrate with 99mTc-HMPAO than with 123I-IMP. SPECT with both tracers is recommended to follow the evolution of strokes in terms of regional cerebral blood flow and tissue metabolism.

  5. Evolution of brain imaging instrumentation.

    PubMed

    Abraham, Tony; Feng, Janine

    2011-05-01

    Computed tomography (CT) and static magnetic resonance imaging (MRI) are now the most common imaging modalities used for anatomic evaluation of pathologic processes affecting the brain. By contrast, radionuclide-based methods, including planar imaging, single-photon emission computed tomography (SPECT), and positron emission tomography (PET), are the most widely used methods for evaluating brain function. SPECT and PET have been evolving for a longer time than CT and MRI and have made significant contributions to understanding brain function. The pioneering work on cerebral flow early in the last century laid the foundation of measurement with radioactive gases. This was initially performed with scintillation counters, which gave way to single, then multiple scintillation and multiprobe detectors. The invention of rectilinear scanners, MARK series, Anger cameras, and SPECT imaging further advanced nuclear medicine's role in brain imaging. Measurement of regional cerebral blood flow by SPECT provides pathophysiologic information that directs patient management in a variety of central nervous disorders (CNS), with the greatest clinical impact found in cerebrovascular disease and seizure disorder. In the former, SPECT not only provides means of early detection and localization of acute strokes but can also direct thrombolysis and determine prognosis in the postcerebrovascular accident period. With respect to the latter, ictal SPECT can localize seizure foci so that patients with refractory disease can potentially undergo surgical resection of the affected area. In contrast to brain SPECT, brain PET images reflect regional cerebral metabolism. Because of neurovascular coupling, findings on SPECT and PET images are often comparable. PET, however, still has improved spatial resolution and is therefore more sensitive than SPECT, particularly in the evaluation of dementias. Brain PET instrumentation has greatly evolved from its infancy, when it was used in regional

  6. Siblings with the adult-onset slowly progressive type of pantothenate kinase-associated neurodegeneration and a novel mutation, Ile346Ser, in PANK2: clinical features and (99m)Tc-ECD brain perfusion SPECT findings.

    PubMed

    Doi, Hiroshi; Koyano, Shigeru; Miyatake, Satoko; Matsumoto, Naomichi; Kameda, Tomoaki; Tomita, Atsuko; Miyaji, Yosuke; Suzuki, Yume; Sawaishi, Yukio; Kuroiwa, Yoshiyuki

    2010-03-15

    Pantothenate kinase-associated neurodegeneration (PKAN), formerly known as Hallervorden-Spatz syndrome (HSS), is an autosomal recessive neurodegenerative disorder characterized by iron accumulation in the brain. Mutations in the pantothenate kinase 2 (PANK2) gene are known to be responsible for PKAN. Several studies have revealed correlations between clinical phenotypes and particular PANK2 mutations. The adult-onset slowly progressive type of PKAN with PANK2 mutations is very rare. In this report, we describe siblings with the adult-onset slowly progressive type of PKAN with a novel mutation, Ile346Ser, in PANK2. The siblings had the same mutation in PANK2 and had common clinical signs such as misalignment of teeth, a high arched palate, hollow feet, a slight cognitive decline, and an apparent executive dysfunction, although they showed different patterns of movement disorders. Thus, even if PKAN patients have identical mutations, it is likely that they will present with different types of movement disorders. Brain perfusion single photon emission computed tomography in both patients showed decreased regional cerebral blood flow in the bilateral frontoparietal lobes, the globus pallidus, the striatum, and around the ventriculus quartus. Cardiac uptake of [(123)I] meta-iodobenzylguanidine was normal in both patients. Analysis of genotype-phenotype correlations and the elucidation of mutational effects on pantothenate kinase 2 function, expression, and structure are important for understanding the mechanisms of PKAN.

  7. SPECT (single photon emission computed tomography) in pediatrics.

    PubMed

    Chiron, Catherine

    2013-01-01

    Surgery of focal epilepsies in childhood has largely benefited from the recent advances of the noninvasive functional imaging techniques, particularly SPECT which presurgically contributes to the localization of the seizure onset zone, in order to select the patients, decide the optimal placement of intracranial electrodes, and plan the resection. Peri-ictal SPECT (ictal and postictal) proved especially useful when video-EEG is not contributory, when MRI looks normal or shows multiple abnormalities, or in cases of discrepant findings within the presurgery workup. Because of a poor temporal resolution, peri-ictal SPECT must be coupled with video-EEG. Multimodal imaging so-called SISCOM (peri-ictal - interictal SPECT subtraction image superimposed on MRI) increases the sensitivity of peri-ictal SPECT by about 70% and makes it a good predictor of seizure-free outcome after surgery. In addition, interictal SPECT occasionally provides some interesting results regarding functional cortical maturation and learning disorders in childhood.

  8. Support vector machine-based classification of neuroimages in Alzheimer's disease: direct comparison of FDG-PET, rCBF-SPECT and MRI data acquired from the same individuals.

    PubMed

    Ferreira, Luiz K; Rondina, Jane M; Kubo, Rodrigo; Ono, Carla R; Leite, Claudia C; Smid, Jerusa; Bottino, Cassio; Nitrini, Ricardo; Busatto, Geraldo F; Duran, Fabio L; Buchpiguel, Carlos A

    2017-10-02

    To conduct the first support vector machine (SVM)-based study comparing the diagnostic accuracy of T1-weighted magnetic resonance imaging (T1-MRI), F-fluorodeoxyglucose-positron emission tomography (FDG-PET) and regional cerebral blood flow single-photon emission computed tomography (rCBF-SPECT) in Alzheimer's disease (AD). Brain T1-MRI, FDG-PET and rCBF-SPECT scans were acquired from a sample of mild AD patients (n=20) and healthy elderly controls (n=18). SVM-based diagnostic accuracy indices were calculated using whole-brain information and leave-one-out cross-validation. The accuracy obtained using PET and SPECT data were similar. PET accuracy was 68∼71% and area under curve (AUC) 0.77∼0.81; SPECT accuracy was 68∼74% and AUC 0.75∼0.79, and both had better performance than analysis with T1-MRI data (accuracy of 58%, AUC 0.67). The addition of PET or SPECT to MRI produced higher accuracy indices (68∼74%; AUC: 0.74∼0.82) than T1-MRI alone, but these were not clearly superior to the isolated neurofunctional modalities. In line with previous evidence, FDG-PET and rCBF-SPECT more accurately identified patients with AD than T1-MRI, and the addition of either PET or SPECT to T1-MRI data yielded increased accuracy. The comparable SPECT and PET performances, directly demonstrated for the first time in the present study, support the view that rCBF-SPECT still has a role to play in AD diagnosis.

  9. Functional neuroimaging in epilepsy: FDG PET and ictal SPECT.

    PubMed Central

    Lee, D. S.; Lee, S. K.; Lee, M. C.

    2001-01-01

    Epileptogenic zones can be localized by F-18 fluorodeoxyglucose positron emission tomography (FDG PET) and ictal single-photon emission computed tomography(SPECT). In medial temporal lobe epilepsy, the diagnostic sensitivity of FDG PET or ictal SPECT is excellent, however, the sensitivity of MRI is so high that the incremental sensitivity by FDG PET or ictal SPECT has yet to be proven. When MRI findings are ambiguous or normal, or discordant with those of ictal EEG, FDG PET and ictal SPECT are helpful for localization without the need for invasive ictal EEG. In neocortical epilepsy, the sensitivities of FDG PET or ictal SPECT are fair. However, because almost a half of the patients are normal on MRI, FDG PET and ictal SPECT are helpful for localization or at least for lateralization in these non-lesional epilepsies in order to guide the subdural insertion of electrodes. Interpretation of FDG PET has been recently advanced by voxel-based analysis and automatic volume of interest analysis based on a population template. Both analytical methods confirmed the performance of previous visual interpretation results. Ictal SPECT was analyzed using subtraction methods(coregistered to MRI) and voxel-based analysis. Rapidity of injection of tracers, HMPAO versus ECD, and repeated ictal SPECT, which remain the technical issues of ictal SPECT, are detailed. PMID:11748346

  10. Perfusion SPECT studies with mapping of Brodmann areas in differentiating Alzheimer's disease from frontotemporal degeneration syndromes.

    PubMed

    Valotassiou, Varvara; Papatriantafyllou, John; Sifakis, Nikolaos; Tzavara, Chara; Tsougos, Ioannis; Kapsalaki, Eftychia; Hadjigeorgiou, George; Georgoulias, Panagiotis

    2012-12-01

    The aim of this study was to evaluate the contribution of brain perfusion single-photon emission computed tomography (SPECT) studies with mapping of Brodmann areas (BAs) in the differential diagnosis between Alzheimer's disease (AD) and frontotemporal degeneration (FTLD) syndromes. Thirty-nine patients with AD and 73 patients with FTLD syndromes [behavioural variant FTLD (bvFTLD); language variant FTLD (lvFTLD), including semantic dementia (SD) and progressive nonfluent aphasia (PNFA); and corticobasal degeneration (CBD)/progressive supranuclear palsy (PSP) syndromes] underwent brain perfusion SPECT. The NeuroGam software was used for the semiquantitative evaluation of perfusion in BAs of the left (L) and right (R) hemispheres. Compared with those in AD patients, BAs with statistically significant hypoperfusion were found in the prefrontal, orbitofrontal and cingulated cortices and Broca's areas of FTLD and bvFTLD patients; in the temporal and prefrontal cortices and Broca's areas of lvFTLD patients; in the left temporal gyrus of SD patients; in premotor and supplementary motor, prefrontal, orbitofrontal, temporal and anterior cingulated cortices and Broca's areas of PNFA patients; and in the prefrontal, temporal, posterior cingulated and primary and secondary visual cortices of CBD/PSP patients. BA 46R could differentiate AD patients from FTLD and bvFTLD patients; 21L and 25L were found to be independent predictors for lvFTLD in comparison with AD, and 25R, 21L and 23R could differentiate AD patients from PNFA, SD and CBD/PSP patients, respectively. Brain perfusion SPECT with BA mapping in AD and FTLD patients could improve the definition of brain areas that are specifically implicated in these disorders, resulting in a more accurate differential diagnosis.

  11. Silicon Detectors for PET and SPECT

    NASA Astrophysics Data System (ADS)

    Cochran, Eric R.

    Silicon detectors use state-of-the-art electronics to take advantage of the semiconductor properties of silicon to produce very high resolution radiation detectors. These detectors have been a fundamental part of high energy, nuclear, and astroparticle physics experiments for decades, and they hold great potential for significant gains in both PET and SPECT applications. Two separate prototype nuclear medicine imaging systems have been developed to explore this potential. Both devices take advantage of the unique properties of high resolution pixelated silicon detectors, designed and developed as part of the CIMA collaboration and built at The Ohio State University. The first prototype is a Compton SPECT imaging system. Compton SPECT, also referred to as electronic collimation, is a fundamentally different approach to single photon imaging from standard gamma cameras. It removes the inherent coupling of spatial resolution and sensitivity in mechanically collimated systems and provides improved performance at higher energies. As a result, Compton SPECT creates opportunities for the development of new radiopharmaceuticals based on higher energy isotopes as well as opportunities to expand the use of current isotopes such as 131I due to the increased resolution and sensitivity. The Compton SPECT prototype consists of a single high resolution silicon detector, configured in a 2D geometry, in coincidence with a standard NaI scintillator detector. Images of point sources have been taken for 99mTc (140 keV), 131I (364keV), and 22Na (511 keV), demonstrating the performance of high resolution silicon detectors in a Compton SPECT system. Filtered back projection image resolutions of 10 mm, 7.5 mm, and 6.7 mm were achieved for the three different sources respectively. The results compare well with typical SPECT resolutions of 5-15 mm and validate the claims of improved performance in Compton SPECT imaging devices at higher source energies. They also support the potential of

  12. New Approaches in SPECT Breast Imaging

    DTIC Science & Technology

    2005-07-01

    the use of their breast and torso phantoms. The software package, "SPECTER", developed by Tim Turkington, was used to analyze and display the phantom...breast images. The software package, "SPECT-MAP", developed by James Bowsher, was used for reconstructions. VI. REFERENCES [1] Tornai MP, Bowsher JE...based software . and standard errors of the mean. No attenuation or scatter corrections were taken into account in For a given statistical ensemble of

  13. Accelerated GPU based SPECT Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Garcia, Marie-Paule; Bert, Julien; Benoit, Didier; Bardiès, Manuel; Visvikis, Dimitris

    2016-06-01

    Monte Carlo (MC) modelling is widely used in the field of single photon emission computed tomography (SPECT) as it is a reliable technique to simulate very high quality scans. This technique provides very accurate modelling of the radiation transport and particle interactions in a heterogeneous medium. Various MC codes exist for nuclear medicine imaging simulations. Recently, new strategies exploiting the computing capabilities of graphical processing units (GPU) have been proposed. This work aims at evaluating the accuracy of such GPU implementation strategies in comparison to standard MC codes in the context of SPECT imaging. GATE was considered the reference MC toolkit and used to evaluate the performance of newly developed GPU Geant4-based Monte Carlo simulation (GGEMS) modules for SPECT imaging. Radioisotopes with different photon energies were used with these various CPU and GPU Geant4-based MC codes in order to assess the best strategy for each configuration. Three different isotopes were considered: 99m Tc, 111In and 131I, using a low energy high resolution (LEHR) collimator, a medium energy general purpose (MEGP) collimator and a high energy general purpose (HEGP) collimator respectively. Point source, uniform source, cylindrical phantom and anthropomorphic phantom acquisitions were simulated using a model of the GE infinia II 3/8" gamma camera. Both simulation platforms yielded a similar system sensitivity and image statistical quality for the various combinations. The overall acceleration factor between GATE and GGEMS platform derived from the same cylindrical phantom acquisition was between 18 and 27 for the different radioisotopes. Besides, a full MC simulation using an anthropomorphic phantom showed the full potential of the GGEMS platform, with a resulting acceleration factor up to 71. The good agreement with reference codes and the acceleration factors obtained support the use of GPU implementation strategies for improving computational efficiency

  14. Accelerated GPU based SPECT Monte Carlo simulations.

    PubMed

    Garcia, Marie-Paule; Bert, Julien; Benoit, Didier; Bardiès, Manuel; Visvikis, Dimitris

    2016-06-07

    Monte Carlo (MC) modelling is widely used in the field of single photon emission computed tomography (SPECT) as it is a reliable technique to simulate very high quality scans. This technique provides very accurate modelling of the radiation transport and particle interactions in a heterogeneous medium. Various MC codes exist for nuclear medicine imaging simulations. Recently, new strategies exploiting the computing capabilities of graphical processing units (GPU) have been proposed. This work aims at evaluating the accuracy of such GPU implementation strategies in comparison to standard MC codes in the context of SPECT imaging. GATE was considered the reference MC toolkit and used to evaluate the performance of newly developed GPU Geant4-based Monte Carlo simulation (GGEMS) modules for SPECT imaging. Radioisotopes with different photon energies were used with these various CPU and GPU Geant4-based MC codes in order to assess the best strategy for each configuration. Three different isotopes were considered: (99m) Tc, (111)In and (131)I, using a low energy high resolution (LEHR) collimator, a medium energy general purpose (MEGP) collimator and a high energy general purpose (HEGP) collimator respectively. Point source, uniform source, cylindrical phantom and anthropomorphic phantom acquisitions were simulated using a model of the GE infinia II 3/8" gamma camera. Both simulation platforms yielded a similar system sensitivity and image statistical quality for the various combinations. The overall acceleration factor between GATE and GGEMS platform derived from the same cylindrical phantom acquisition was between 18 and 27 for the different radioisotopes. Besides, a full MC simulation using an anthropomorphic phantom showed the full potential of the GGEMS platform, with a resulting acceleration factor up to 71. The good agreement with reference codes and the acceleration factors obtained support the use of GPU implementation strategies for improving computational

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

    PubMed

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

    2008-01-01

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

  16. Reconstruction of dynamic gated cardiac SPECT

    SciTech Connect

    Jin Mingwu; Yang Yongyi; King, Michael A.

    2006-11-15

    In this paper we propose an image reconstruction procedure which aims to unify gated single photon emission computed tomography (SPECT) and dynamic SPECT into a single method. We divide the cardiac cycle into a number of gate intervals as in gated SPECT, but treat the tracer distribution for each gate as a time-varying signal. By using both dynamic and motion-compensated temporal regularization, our reconstruction procedure will produce an image sequence that shows both cardiac motion and time-varying tracer distribution simultaneously. To demonstrate the proposed reconstruction method, we simulated gated cardiac perfusion imaging using the gated mathematical cardiac-torso (gMCAT) phantom with Tc99m-Teboroxime as the imaging agent. Our results show that the proposed method can produce more accurate reconstruction of gated dynamic images than independent reconstruction of individual gate frames with spatial smoothness alone. In particular, our results show that the former could improve the contrast to noise ratio of a simulated perfusion defect by as much as 100% when compared to the latter.

  17. SPECT and PET in ischemic heart failure.

    PubMed

    Angelidis, George; Giamouzis, Gregory; Karagiannis, Georgios; Butler, Javed; Tsougos, Ioannis; Valotassiou, Varvara; Giannakoulas, George; Dimakopoulos, Nikolaos; Xanthopoulos, Andrew; Skoularigis, John; Triposkiadis, Filippos; Georgoulias, Panagiotis

    2017-02-02

    Heart failure is a common clinical syndrome associated with significant morbidity and mortality worldwide. Ischemic heart disease is the leading cause of heart failure, at least in the industrialized countries. Proper diagnosis of the syndrome and management of patients with heart failure require anatomical and functional information obtained through various imaging modalities. Nuclear cardiology techniques play a main role in the evaluation of heart failure. Myocardial single photon emission computed tomography (SPECT) with thallium-201 or technetium-99 m labelled tracers offer valuable data regarding ventricular function, myocardial perfusion, viability, and intraventricular synchronism. Moreover, positron emission tomography (PET) permits accurate evaluation of myocardial perfusion, metabolism, and viability, providing high-quality images and the ability of quantitative analysis. As these imaging techniques assess different parameters of cardiac structure and function, variations of sensitivity and specificity have been reported among them. In addition, the role of SPECT and PET guided therapy remains controversial. In this comprehensive review, we address these controversies and report the advances in patient's investigation with SPECT and PET in ischemic heart failure. Furthermore, we present the innovations in technology that are expected to strengthen the role of nuclear cardiology modalities in the investigation of heart failure.

  18. SPECT and PET Imaging of Meningiomas

    PubMed Central

    Valotassiou, Varvara; Leondi, Anastasia; Angelidis, George; Psimadas, Dimitrios; Georgoulias, Panagiotis

    2012-01-01

    Meningiomas arise from the meningothelial cells of the arachnoid membranes. They are the most common primary intracranial neoplasms and represent about 20% of all intracranial tumors. They are usually diagnosed after the third decade of life and they are more frequent in women than in men. According to the World Health Organization (WHO) criteria, meningiomas can be classified into grade I meningiomas, which are benign, grade II (atypical) and grade III (anaplastic) meningiomas, which have a much more aggressive clinical behaviour. Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) are routinely used in the diagnostic workup of patients with meningiomas. Molecular Nuclear Medicine Imaging with Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET) could provide complementary information to CT and MRI. Various SPECT and PET tracers may provide information about cellular processes and biological characteristics of meningiomas. Therefore, SPECT and PET imaging could be used for the preoperative noninvasive diagnosis and differential diagnosis of meningiomas, prediction of tumor grade and tumor recurrence, response to treatment, target volume delineation for radiation therapy planning, and distinction between residual or recurrent tumour from scar tissue. PMID:22623896

  19. SPECT and PET imaging of meningiomas.

    PubMed

    Valotassiou, Varvara; Leondi, Anastasia; Angelidis, George; Psimadas, Dimitrios; Georgoulias, Panagiotis

    2012-01-01

    Meningiomas arise from the meningothelial cells of the arachnoid membranes. They are the most common primary intracranial neoplasms and represent about 20% of all intracranial tumors. They are usually diagnosed after the third decade of life and they are more frequent in women than in men. According to the World Health Organization (WHO) criteria, meningiomas can be classified into grade I meningiomas, which are benign, grade II (atypical) and grade III (anaplastic) meningiomas, which have a much more aggressive clinical behaviour. Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) are routinely used in the diagnostic workup of patients with meningiomas. Molecular Nuclear Medicine Imaging with Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET) could provide complementary information to CT and MRI. Various SPECT and PET tracers may provide information about cellular processes and biological characteristics of meningiomas. Therefore, SPECT and PET imaging could be used for the preoperative noninvasive diagnosis and differential diagnosis of meningiomas, prediction of tumor grade and tumor recurrence, response to treatment, target volume delineation for radiation therapy planning, and distinction between residual or recurrent tumour from scar tissue.

  20. SPECT detectors: the Anger Camera and beyond.

    PubMed

    Peterson, Todd E; Furenlid, Lars R

    2011-09-07

    The development of radiation detectors capable of delivering spatial information about gamma-ray interactions was one of the key enabling technologies for nuclear medicine imaging and, eventually, single-photon emission computed tomography (SPECT). The continuous sodium iodide scintillator crystal coupled to an array of photomultiplier tubes, almost universally referred to as the Anger Camera after its inventor, has long been the dominant SPECT detector system. Nevertheless, many alternative materials and configurations have been investigated over the years. Technological advances as well as the emerging importance of specialized applications, such as cardiac and preclinical imaging, have spurred innovation such that alternatives to the Anger Camera are now part of commercial imaging systems. Increased computing power has made it practical to apply advanced signal processing and estimation schemes to make better use of the information contained in the detector signals. In this review we discuss the key performance properties of SPECT detectors and survey developments in both scintillator and semiconductor detectors and their readouts with an eye toward some of the practical issues at least in part responsible for the continuing prevalence of the Anger Camera in the clinic.

  1. SPECT detectors: the Anger Camera and beyond

    PubMed Central

    Peterson, Todd E.; Furenlid, Lars R.

    2011-01-01

    The development of radiation detectors capable of delivering spatial information about gamma-ray interactions was one of the key enabling technologies for nuclear medicine imaging and, eventually, single-photon emission computed tomography (SPECT). The continuous NaI(Tl) scintillator crystal coupled to an array of photomultiplier tubes, almost universally referred to as the Anger Camera after its inventor, has long been the dominant SPECT detector system. Nevertheless, many alternative materials and configurations have been investigated over the years. Technological advances as well as the emerging importance of specialized applications, such as cardiac and preclinical imaging, have spurred innovation such that alternatives to the Anger Camera are now part of commercial imaging systems. Increased computing power has made it practical to apply advanced signal processing and estimation schemes to make better use of the information contained in the detector signals. In this review we discuss the key performance properties of SPECT detectors and survey developments in both scintillator and semiconductor detectors and their readouts with an eye toward some of the practical issues at least in part responsible for the continuing prevalence of the Anger Camera in the clinic. PMID:21828904

  2. SPECT detectors: the Anger Camera and beyond

    NASA Astrophysics Data System (ADS)

    Peterson, Todd E.; Furenlid, Lars R.

    2011-09-01

    The development of radiation detectors capable of delivering spatial information about gamma-ray interactions was one of the key enabling technologies for nuclear medicine imaging and, eventually, single-photon emission computed tomography (SPECT). The continuous sodium iodide scintillator crystal coupled to an array of photomultiplier tubes, almost universally referred to as the Anger Camera after its inventor, has long been the dominant SPECT detector system. Nevertheless, many alternative materials and configurations have been investigated over the years. Technological advances as well as the emerging importance of specialized applications, such as cardiac and preclinical imaging, have spurred innovation such that alternatives to the Anger Camera are now part of commercial imaging systems. Increased computing power has made it practical to apply advanced signal processing and estimation schemes to make better use of the information contained in the detector signals. In this review we discuss the key performance properties of SPECT detectors and survey developments in both scintillator and semiconductor detectors and their readouts with an eye toward some of the practical issues at least in part responsible for the continuing prevalence of the Anger Camera in the clinic.

  3. Dual head HIPDM SPECT imaging in the differential diagnosis of dementia with MR and CT correlation

    SciTech Connect

    Wellman, H.N.; Gilmor, R.; Hendrie, H.; Mock, B.; Kapuscinski, A.; Appledorn, C.R.; Krepshaw, J.

    1985-05-01

    Dual head SPECT brain imaging was performed in 25 patients with a clinical diagnosis of dementia approximately one-half hour after a 5mCi dose of high purity (p,5n) I-123 HIPDM (N,N,N'-Trimethyl-N'-(2-hydroxy-3-methyl-5-iodobenzyl)- 1,3-propane diamine). Tomographic reconstruction used a 30th order, moderate cutoff (0.2) Butterworth filter found previously to optimize low noise and conspicuity. Most patients had CT and MR imaging and some patients were studied more than once. In approximately one-half of patients referred with a diagnosis of dementia of the Alzheimer's type, SPECT results were consistent with multiple infarct dementia (MID). MR studies in most of these patients with MID demonstrated multiple white matter defects correlating with multiple gray matter defects seen with SPECT and consistent with angiogenic disease of the Binswanger's type. While CT demonstrated cortical abnormalities in some patients, the findings were often nonspecific with enlarged ventricles and widened sulci.

  4. Cerebral Hypoperfusion in Hereditary Coproporphyria (HCP): A Single Photon Emission Computed Tomography (SPECT) Study

    PubMed Central

    Valle, Guido; Guida, Claudio Carmine; Nasuto, Michelangelo; Totaro, Manuela; Aucella, Filippo; Frusciante, Vincenzo; Di Mauro, Lazzaro; Potenza, Adele; Savino, Maria; Stanislao, Mario; Popolizio, Teresa; Guglielmi, Giuseppe; Giagulli, Vito Angelo; Guastamacchia, Edoardo; Triggiani, Vincenzo

    2016-01-01

    Background: Hereditary Coproporphyria (HCP) is characterized by abdominal pain, neurologic symptoms and psychiatric disorders, even if it might remain asymptomatic. The pathophysiology of both neurologic and psychiatric symptoms is not fully understood. Therefore, aiming to evaluate a possible role of brain blood flow disorders, we have retrospectively investigated cerebral perfusion patterns in Single Photon Emission Computed Tomography (SPECT) studies in HCP patients. Materials & Methods: We retrospectively evaluated the medical records of patients diagnosed as being affected by HCP. A total of seven HCP patients had been submitted to brain perfusion SPECT study with 99mTc-Exametazime (hexamethylpropyleneamine oxime, HMPAO) or with its functionally equivalent 99mTc-Bicisate (ECD or Neurolite) according with common procedures. In 3 patients the scintigraphic study had been repeated for a second time after the first evaluation at 3, 10 and 20 months, respectively. All the studied subjects had been also submitted to an electromyographic and a Magnetic Resonance Imaging (MRI) study of the brain. Results: Mild to moderate perfusion defects were detected in temporal lobes (all 7 patients), frontal lobes (6 patients) and parietal lobes (4 patients). Occipital lobe, basal ganglia and cerebellar involvement were never observed. In the three subjects in which SPECT study was repeated, some recovery of hypo-perfused areas and appearance of new perfusion defects in other brain regions have been found. In all patients electromyography resulted normal and MRI detected few unspecific gliotic lesions only in one patient. Discussion & Conclusions: Since perfusion abnormalities were usually mild to moderate, this can probably explain the normal pattern observed at MRI studies. Compared to MRI, SPECT with 99mTc showed higher sensitivity in HCP patients. Changes observed in HCP patients who had more than one study suggest that transient perfusion defects might be due to a brain

  5. Cerebral Hypoperfusion in Hereditary Coproporphyria (HCP): A Single Photon Emission Computed Tomography (SPECT) Study.

    PubMed

    Valle, Guido; Guida, Claudio Carmine; Nasuto, Michelangelo; Totaro, Manuela; Aucella, Filippo; Frusciante, Vincenzo; Di Mauro, Lazzaro; Potenza, Adele; Savino, Maria; Stanislao, Mario; Popolizio, Teresa; Guglielmi, Giuseppe; Giagulli, Vito Angelo; Guastamacchia, Edoardo; Triggiani, Vincenzo

    2016-01-01

    Hereditary Coproporphyria (HCP) is characterized by abdominal pain, neurologic symptoms and psychiatric disorders, even if it might remain asymptomatic. The pathophysiology of both neurologic and psychiatric symptoms is not fully understood. Therefore, aiming to evaluate a possible role of brain blood flow disorders, we have retrospectively investigated cerebral perfusion patterns in Single Photon Emission Computed Tomography (SPECT) studies in HCP patients. We retrospectively evaluated the medical records of patients diagnosed as being affected by HCP. A total of seven HCP patients had been submitted to brain perfusion SPECT study with 99mTc-Exametazime (hexamethylpropyleneamine oxime, HMPAO) or with its functionally equivalent 99mTc-Bicisate (ECD or Neurolite) according with common procedures. In 3 patients the scintigraphic study had been repeated for a second time after the first evaluation at 3, 10 and 20 months, respectively. All the studied subjects had been also submitted to an electromyographic and a Magnetic Resonance Imaging (MRI) study of the brain. Mild to moderate perfusion defects were detected in temporal lobes (all 7 patients), frontal lobes (6 patients) and parietal lobes (4 patients). Occipital lobe, basal ganglia and cerebellar involvement were never observed. In the three subjects in which SPECT study was repeated, some recovery of hypo-perfused areas and appearance of new perfusion defects in other brain regions have been found. In all patients electromyography resulted normal and MRI detected few unspecific gliotic lesions only in one patient. Discussion & Conclusions: Since perfusion abnormalities were usually mild to moderate, this can probably explain the normal pattern observed at MRI studies. Compared to MRI, SPECT with 99mTc showed higher sensitivity in HCP patients. Changes observed in HCP patients who had more than one study suggest that transient perfusion defects might be due to a brain artery spasm possibly leading to psychiatric

  6. Evaluation of the olfactory nerve transport function by SPECT-MRI fusion image with nasal thallium-201 administration.

    PubMed

    Shiga, Hideaki; Taki, Junichi; Yamada, Masato; Washiyama, Kohshin; Amano, Ryohei; Matsuura, Yukihiro; Matsui, Osamu; Tatsutomi, Shinji; Yagi, Sayaka; Tsuchida, Asuka; Yoshizaki, Tomokazu; Furukawa, Mitsuru; Kinuya, Seigo; Miwa, Takaki

    2011-12-01

    The aim of this study was to visualize the human olfactory transport pathway to the brain by performing imaging after nasal thallium-201 ((201)Tl) administration. Healthy volunteers were enrolled in this study after giving informed consent (five males, 35-51 years old). The subjects were nasally administered (201)TlCl into either the olfactory cleft. Twenty-four hours later, uptake of (201)Tl was detected by a single photon emission computed tomography (SPECT)/X-ray computed tomography hybrid system. For each subject, an MRI image was obtained and merged with the SPECT image. The peak of the (201)Tl uptake entered into the olfactory bulb in the anterior skull base through the cribriform lamina 24 h after nasal administration of (201)Tl. No participant had olfactory disturbance after treatment. Nasal (201)Tl administration was safely used to assess the direct pathway to the brain via the nose in healthy volunteers with normal olfactory threshold.

  7. A multiresolution restoration method for cardiac SPECT

    NASA Astrophysics Data System (ADS)

    Franquiz, Juan Manuel

    Single-photon emission computed tomography (SPECT) is affected by photon attenuation and image blurring due to Compton scatter and geometric detector response. Attenuation correction is important to increase diagnostic accuracy of cardiac SPECT. However, in attenuation-corrected scans, scattered photons from radioactivity in the liver could produce a spillover of counts into the inferior myocardial wall. In the clinical setting, blurring effects could be compensated by restoration with Wiener and Metz filters. Inconveniences of these procedures are that the Wiener filter depends upon the power spectra of the object image and noise, which are unknown, while Metz parameters have to be optimized by trial and error. This research develops an alternative restoration procedure based on a multiresolution denoising and regularization algorithm. It was hypothesized that this representation leads to a more straightforward and automatic restoration than conventional filters. The main objective of the research was the development and assessment of the multiresolution algorithm for compensating the liver spillover artifact. The multiresolution algorithm decomposes original SPECT projections into a set of sub-band frequency images. This allows a simple denoising and regularization procedure by discarding high frequency channels and performing inversion only in low and intermediate frequencies. The method was assessed in bull's eye polar maps and short- axis attenuation-corrected reconstructions of a realistic cardiac-chest phantom with a custom-made liver insert and different 99mTc liver-to-heart activity ratios. Inferior myocardial defects were simulated in some experiments. The cardiac phantom in free air was considered as the gold standard reference. Quantitative analysis was performed by calculating contrast of short- axis slices and the normalized chi-square measure, defect size and mean and standard deviation of polar map counts. The performance of the multiresolution

  8. Design and assessment of cardiac SPECT systems

    NASA Astrophysics Data System (ADS)

    Lee, Chih-Jie

    Single-photon emission computed tomography (SPECT) is a modality widely used to detect myocardial ischemia and myocardial infarction. Objectively assessing and comparing different SPECT systems is important so that the best detectability of cardiac defects can be achieved. Whitaker, Clarkson, and Barrett's study on the scanning linear observer (SLO) shows that the SLO can be used to estimate the location and size of signals. One major advantage of the SLO is that it can be used with projection data rather than reconstruction data. Thus, this observer model assesses overall hardware performance independent by any reconstruction algorithm. In addition, we will show that the run time of image-quality studies is significantly reduced. Several systems derived from the GE CZT-based dedicated cardiac SPECT camera Discovery 530c design, which is officially named the Alcyone Technology: Discovery NM 530c, were assessed using the performance of the SLO for the task of detecting cardiac defects and estimating the properties of the defects. Clinically, hearts can be virtually segmented into three coronary artery territories: left anterior descending artery (LAD), left circumflex artery (LCX), and right coronary artery (RCA). One of the most important functions of a cardiac SPECT system is to produce images from which a radiologist can correctly predict in which territory the defect exists. A good estimation of the defect extent from the images is also very helpful for determining the seriousness of the myocardial ischemia. In this dissertation, both locations and extent of defects were estimated by the SLO, and system performance was assessed using localization receiver operating characteristic (LROC) / estimation receiver operating characteristic (EROC) curves. Area under LROC curve (AULC) / area under EROC curve (AUEC) and true positive fraction (TPF) at specific false positive fraction (FPF) can be treated as the gures of merit (FOMs). As the results will show, a

  9. Quantitative Monte Carlo-based holmium-166 SPECT reconstruction

    SciTech Connect

    Elschot, Mattijs; Smits, Maarten L. J.; Nijsen, Johannes F. W.; Lam, Marnix G. E. H.; Zonnenberg, Bernard A.; Bosch, Maurice A. A. J. van den; Jong, Hugo W. A. M. de; Viergever, Max A.

    2013-11-15

    Purpose: Quantitative imaging of the radionuclide distribution is of increasing interest for microsphere radioembolization (RE) of liver malignancies, to aid treatment planning and dosimetry. For this purpose, holmium-166 ({sup 166}Ho) microspheres have been developed, which can be visualized with a gamma camera. The objective of this work is to develop and evaluate a new reconstruction method for quantitative {sup 166}Ho SPECT, including Monte Carlo-based modeling of photon contributions from the full energy spectrum.Methods: A fast Monte Carlo (MC) simulator was developed for simulation of {sup 166}Ho projection images and incorporated in a statistical reconstruction algorithm (SPECT-fMC). Photon scatter and attenuation for all photons sampled from the full {sup 166}Ho energy spectrum were modeled during reconstruction by Monte Carlo simulations. The energy- and distance-dependent collimator-detector response was modeled using precalculated convolution kernels. Phantom experiments were performed to quantitatively evaluate image contrast, image noise, count errors, and activity recovery coefficients (ARCs) of SPECT-fMC in comparison with those of an energy window-based method for correction of down-scattered high-energy photons (SPECT-DSW) and a previously presented hybrid method that combines MC simulation of photopeak scatter with energy window-based estimation of down-scattered high-energy contributions (SPECT-ppMC+DSW). Additionally, the impact of SPECT-fMC on whole-body recovered activities (A{sup est}) and estimated radiation absorbed doses was evaluated using clinical SPECT data of six {sup 166}Ho RE patients.Results: At the same noise level, SPECT-fMC images showed substantially higher contrast than SPECT-DSW and SPECT-ppMC+DSW in spheres ≥17 mm in diameter. The count error was reduced from 29% (SPECT-DSW) and 25% (SPECT-ppMC+DSW) to 12% (SPECT-fMC). ARCs in five spherical volumes of 1.96–106.21 ml were improved from 32%–63% (SPECT-DSW) and 50%–80

  10. Evaluation of reconstruction techniques in regional cerebral blood flow SPECT using trade-off plots: a Monte Carlo study.

    PubMed

    Olsson, Anna; Arlig, Asa; Carlsson, Gudrun Alm; Gustafsson, Agnetha

    2007-09-01

    The image quality of single photon emission computed tomography (SPECT) depends on the reconstruction algorithm used. The purpose of the present study was to evaluate parameters in ordered subset expectation maximization (OSEM) and to compare systematically with filtered back-projection (FBP) for reconstruction of regional cerebral blood flow (rCBF) SPECT, incorporating attenuation and scatter correction. The evaluation was based on the trade-off between contrast recovery and statistical noise using different sizes of subsets, number of iterations and filter parameters. Monte Carlo simulated SPECT studies of a digital human brain phantom were used. The contrast recovery was calculated as measured contrast divided by true contrast. Statistical noise in the reconstructed images was calculated as the coefficient of variation in pixel values. A constant contrast level was reached above 195 equivalent maximum likelihood expectation maximization iterations. The choice of subset size was not crucial as long as there were > or = 2 projections per subset. The OSEM reconstruction was found to give 5-14% higher contrast recovery than FBP for all clinically relevant noise levels in rCBF SPECT. The Butterworth filter, power 6, achieved the highest stable contrast recovery level at all clinically relevant noise levels. The cut-off frequency should be chosen according to the noise level accepted in the image. Trade-off plots are shown to be a practical way of deciding the number of iterations and subset size for the OSEM reconstruction and can be used for other examination types in nuclear medicine.

  11. A small-animal imaging system capable of multipinhole circular/helical SPECT and parallel-hole SPECT

    PubMed Central

    Qian, Jianguo; Bradley, Eric L.; Majewski, Stan; Popov, Vladimir; Saha, Margaret S.; Smith, Mark F.; Weisenberger, Andrew G.; Welsh, Robert E.

    2008-01-01

    We have designed and built a small animal single photon emission computed tomography (SPECT) imaging system equipped with parallel-hole and multipinhole collimators and capable of circular or helical SPECT. Copper-beryllium parallel-hole collimators suitable for imaging the ~35 keV photons from the decay of 125I have been built and installed to achieve useful spatial resolution over a range of object-detector distances and to reduce imaging time on our dual-detector array. To address the resolution limitations in the parallel-hole SPECT and the sensitivity and limited field of view of single-pinhole SPECT, we have incorporated multipinhole circular and helical SPECT in addition to expanding the parallel-hole SPECT capabilities. The pinhole SPECT system is based on a 110 mm diameter circular detector equipped with a pixellated NaI(Tl) scintillator array (1×1×5 mm3/pixel). The helical trajectory is accomplished by two stepping motors controlling the rotation of the detector-support gantry and displacement of the animal bed along the axis of rotation of the gantry. Results obtained in SPECT studies of various phantoms show an enlarged field of view, very good resolution and improved sensitivity using multipinhole circular or helical SPECT. Collimators with one, three and five 1 mm diameter pinholes have been implemented and compared in these tests. Our objective is to develop a system on which one may readily select a suitable mode of either parallel-hole SPECT or pinhole circular or helical SPECT for a variety of small animal imaging applications. PMID:19701447

  12. The Value of 99mTc ECD SPECT With Statistical Image Analysis on Enhancing the Early Diagnosis of Primary Progressive Aphasia.

    PubMed

    Wei, Cheng-Yu; Chiu, Pai-Yi; Hou, Po-Nien; Matsuda, Hiroshi; Hung, Guang-Uei

    2017-02-01

    A 64-year-old woman with poor short-term memory was first suspected as early Alzheimer disease. Tc ECD brain SPECT was arranged for differential diagnosis. A small area of mild hypoperfusion was noted in the left temporal lobe on conventional display. Further statistical analysis of SPECT with an easy Z-score imaging system showed large areas of distinct hypoperfusion in left precentral and perisylvian cortical areas, compatible with typical pictures of nonfluent variant primary progressive aphasia (PPA), but no involvement in areas characteristic for Alzheimer disease. Further detailed neuropsychological examination and 6 months of clinical follow-up confirmed the final diagnosis of PPA.

  13. Comparison of technetium-99m-HMPAO and technetium-99m-ECD cerebral SPECT images in Alzheimer`s disease

    SciTech Connect

    Dyck, C.H. van; Lin, C.H.; Smith, E.O.

    1996-11-01

    SPECT has shown increasing promise as a diagnostic tool in Alzheimer`s disease (AD). Recently, a new SPECT brain perfusion agent, {sup 99m}Tc-ethyl cysteinate dimer ({sup 99m}Tc-ECD) has emerged with purported advantages in image quality over the established tracer, {sup 99m}Tc-hexamethylpropyleneamine oxime ({sup 99m}Tc-HMPAO). This research aimed to compare cerebral images for ({sup 99m}Tc-HMPAO). This research aimed to compare cerebral images for {sup 99}mTc-HMPAO and {sup 99m}Tc-ECD in discriminating patients with AD form control subjects. 51 refs., 5 figs., 3 tabs.

  14. Prolactin plasma levels and D2-dopamine receptor occupancy measured with IBZM-SPECT.

    PubMed

    Schlegel, S; Schlösser, R; Hiemke, C; Nickel, O; Bockisch, A; Hahn, K

    1996-04-01

    By the application of 123([123I]IBZM), an iodine-labelled dopamine D2-receptor antagonist, brain D2 receptors in humans can be visualized with single photon emission computed tomography (SPECT). The ratio of IBZM binding to striatal regions versus binding to frontal cortex (ST/FC ratio) provided a semiquantitative measurement of D2 receptor binding in the striatum. This study investigated the relationship between receptor occupancy and plasma prolactin levels in 12 male patients treated with haloperidol, benperidol or clozapine. Prolactin levels were positively correlated with D2 receptor occupancy, reflecting at least in part a comparable dopamine receptor antagonism in different dopaminergic pathways.

  15. Patient doses from hybrid SPECT-CT procedures.

    PubMed

    Avramova-Cholakova, S; Dimcheva, M; Petrova, E; Garcheva, M; Dimitrova, M; Palashev, Y; Vassileva, J

    2015-07-01

    The aim of this work is to estimate patient doses from hybrid single-photon emission computed tomography (SPECT) and computed tomography (CT) procedures. The study involved all four SPECT-CT systems in Bulgaria. Effective dose was estimated for about 100 patients per system. Ten types of examinations were considered, representing all diagnostic procedures performed in the SPECT-CT systems. Effective doses from the SPECT component were calculated applying the ICRP 53 and ICRP 80 conversion coefficients. Computed tomography dose index and dose length product were retrospectively obtained from the archives of the systems, and effective doses from the CT component were calculated with CT-Expo software. Parallel estimation of CT component contribution with the National Radiological Protection Board (NRPB) conversion coefficients was performed where applicable. Large variations were found in the current practice of SPECT-CT imaging. Optimisation actions and diagnostic reference levels were proposed.

  16. Concordance between (99m)Tc-ECD SPECT and 18F-FDG PET interpretations in patients with cognitive disorders diagnosed according to NIA-AA criteria.

    PubMed

    Ito, Kimiteru; Shimano, Yasumasa; Imabayashi, Etsuko; Nakata, Yasuhiro; Omachi, Yoshie; Sato, Noriko; Arima, Kunimasa; Matsuda, Hiroshi

    2014-10-01

    The purpose of this study was to clarify the concordance of diagnostic abilities and interobserver agreement between 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) and brain perfusion single photon-emission computed tomography (SPECT) in patients with Alzheimer's disease (AD) who were diagnosed according to the research criteria of the National Institute of Aging-Alzheimer's Association Workshop. Fifty-five patients with "AD and mild cognitive impairment (MCI)" (n = 40) and "non-AD" (n = 15) were evaluated with 18F-FDG PET and (99m)Tc-ethyl cysteinate dimer (ECD) SPECT during an 8-week period. Three radiologists independently graded the regional uptake in the frontal, temporal, parietal, and occipital lobes as well as the precuneus/posterior cingulate cortex in both images. Kappa values were used to determine the interobserver reliability regarding regional uptake. The regions with better interobserver reliability between 18F-FDG PET and (99m)Tc-ECD SPECT were the frontal, parietal, and temporal lobes. The (99m)Tc-ECD SPECT agreement in the occipital lobes was not significant. The frontal, temporal, and parietal lobes showed good correlations between 18F-FDG PET and (99m)Tc-ECD SPECT in the degree of uptake, but the occipital lobe and precuneus/posterior cingulate cortex did not show good correlations. The diagnostic accuracy rates of "AD and MCI" ranged from 60% to 70% in both of the techniques. The degree of uptake on 18F-FDG PET and (99m)Tc-ECD SPECT showed significant correlations in the frontal, temporal, and parietal lobes. The diagnostic abilities of 18F-FDG PET and (99m)Tc-ECD SPECT for "AD and MCI," when diagnosed according to the National Institute of Aging-Alzheimer's Association Workshop criteria, were nearly identical. Copyright © 2014 John Wiley & Sons, Ltd.

  17. Automated segmentation and registration technique for HMPAO-SPECT imaging of Alzheimer's patients

    NASA Astrophysics Data System (ADS)

    Radau, Perry E.; Slomka, Piotr J.; Julin, Per; Svensson, Leif; Wahlund, Lars-Olof

    2000-06-01

    We present an operator-independent software technique for segmentation, realignment and analysis of brain perfusion images, with both voxel-wise and regional quantitation methods. Inter-subject registration with normalized mutual information was tested with simulated defects. Brain perfusion images (HMPAO-SPECT) from 56 subjects (21 AD; 35 controls) were retrospectively analyzed. Templates were created from the 3-D registration of the controls. Automatic segmentation was developed to remove extraneous activity that disrupts registration. Two new registration methods, robust least squares (RLS) and normalized mutual information (NMI) were implemented and compared with sum of absolute differences (CD). The automatic segmentation method caused a registration displacement of 0.4 +/- 0.3 pixels compared with manual segmentation. NMI registration proved to be less adversely effected by simulated defects than RLS or CD. The error in quantitating the patient-template parietal ratio due to mis- registration was 2.0% and 0.5% for 70% and 85% hypoperfusion defects, respectively. The registration processing time was 1.6 min (233 MHz Pentium). The most accurate discriminant utilized a logistic equation parameterized by mean counts of the parietal and temporal regions of the map, (91 +/- 8% Se, 97 +/- 5% Sp). BRASS is a fast, objective software package for single-step analysis of brain SPECT, suitable to aid diagnosis of AD.

  18. Brain single photon emission computed tomography in neonates

    SciTech Connect

    Denays, R.; Van Pachterbeke, T.; Tondeur, M.; Spehl, M.; Toppet, V.; Ham, H.; Piepsz, A.; Rubinstein, M.; Nol, P.H.; Haumont, D. )

    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.

  19. (99m)Tc-labelled nanosystem as tumour imaging agent for SPECT and SPECT/CT modalities.

    PubMed

    Polyák, András; Hajdu, István; Bodnár, Magdolna; Trencsényi, György; Pöstényi, Zita; Haász, Veronika; Jánoki, Gergely; Jánoki, Győző A; Balogh, Lajos; Borbély, János

    2013-06-05

    We report the synthesis, in vitro and in vivo investigation of folate-targeted, biocompatible, biodegradable self-assembled nanoparticles radiolabelled with (99m)Tc, as potential new SPECT or SPECT/CT imaging agent. Nanoparticles with hydrodynamic size in the range of 75-200 nm were prepared by self-assembly of chitosan and folated poly-γ-glutamic acid, and then radiolabelled with (99m)Tc. The nanoparticles target tumour cells overexpressing folate receptors and internalize specifically into them to realize early tumour diagnosis detected by SPECT and SPECT/CT modalities. Rat hepatocellular carcinoma cells were used as model system. Cell specificity and tumour targeting efficacy of these nanosystems were investigated in vitro, and in vivo using SPECT and fusion nanoSPECT/CT imaging. In vitro results showed that the radiolabeled nanosystem was efficiently internalized by tumour cells. Whole-body biodistribution of the new radiolabelled, folate-targeted nanoparticles revealed higher uptake in the tumorous kidney compared to the non-tumorous contralateral side. Uptake by the lungs and thyroids was negligible, which confirmed the stability of the nanoparticles in vivo. In vivo SPECT and SPECT/CT imaging visually reinforced the uptake results and were in accordance with the biodistribution data: the new nanoparticles as a targeted contrast agent improve tumour targeting and are able to detect folate-receptor-overexpressing tumours in animal models with enhanced contrast.

  20. Bayesian learning for cardiac SPECT image interpretation.

    PubMed

    Sacha, Jarosław P; Goodenday, Lucy S; Cios, Krzysztof J

    2002-01-01

    In this paper, we describe a system for automating the diagnosis of myocardial perfusion from single-photon emission computerized tomography (SPECT) images of male and female hearts. Initially we had several thousand of SPECT images, other clinical data and physician-interpreter's descriptions of the images. The images were divided into segments based on the Yale system. Each segment was described by the physician as showing one of the following conditions: normal perfusion, reversible perfusion defect, partially reversible perfusion defect, fixed perfusion defect, defect showing reverse redistribution, equivocal defect or artifact. The physician's diagnosis of overall left ventricular (LV) perfusion, based on the above descriptions, categorizes a study as showing one or more of eight possible conditions: normal, ischemia, infarct and ischemia, infarct, reverse redistribution, equivocal, artifact or LV dysfunction. Because of the complexity of the task, we decided to use the knowledge discovery approach, consisting of these steps: problem understanding, data understanding, data preparation, data mining, evaluating the discovered knowledge and its implementation. After going through the data preparation step, in which we constructed normal gender-specific models of the LV and image registration, we ended up with 728 patients for whom we had both SPECT images and corresponding diagnoses. Another major contribution of the paper is the data mining step, in which we used several new Bayesian learning classification methods. The approach we have taken, namely the six-step knowledge discovery process has proven to be very successful in this complex data mining task and as such the process can be extended to other medical data mining projects.

  1. Myocardial Perfusion SPECT 2015 in Germany

    PubMed Central

    Burchert, Wolfgang; Schäfer, Wolfgang; Hacker, Marcus

    2016-01-01

    Summary Aim The working group Cardiovascular Nuclear Medicine of the German Society of Nuclear Medicine presents the results of the 7th survey of myocardial perfusion SPECT (MPS) of the reporting year 2015. Method 268 questionnaires (173 practices [PR], 67 hospitals [HO], 28 university hospitals [UH]) were evaluated. Results of the last survey from 2012 are set in squared brackets. Results MPS of 121 939 [105 941] patients were reported. 98 % [95 %] of all MPS were performed with Tc-99m radiopharmaceuticals and 2 % [5 %] with Tl-201. 78 % [79 %] of all patients were studied in PR, 14 % [15 %] in HO, and 8 % [6 %] in UH. A pharmacological stress test was performed in 43 % [39 %] (22 % [24 %] adenosine, 20 % [9 %] regadenoson, 1% [6 %] dipyridamole or dobutamine). Attenuation correction was applied in 25 % [2009: 10 %] of MPS. Gated SPECT was performed in 78 % [70 %] of all rest MPS, in 80 % [73 %] of all stress and in 76 % [67 %] of all stress and rest MPS. 53 % [33 %] of all nuclear medicine departments performed MPS scoring by default, whereas 24 % [41 %] did not apply any quantification. 31 % [26 %] of all departments noticed an increase in their counted MPS and 29 % [29 %] no changes. Data from 89 departments which participated in all surveys showed an increase in MPS count of 11.1 % (PR: 12.2 %, HO: 4.8 %, UH: 18.4 %). 70 % [60 %] of the MPS were requested by ambulatory care cardiologists. Conclusion The 2015 MPS survey reveals a high-grade adherence of routine MPS practice to current guidelines. The positive trend in MPS performance and number of MPS already observed in 2012 continues. Educational training remains necessary in the field of SPECT scoring. PMID:27909712

  2. Introduction of novel semiquantitative evaluation of (99m)Tc-MIBI SPECT before and after treatment of glioma.

    PubMed

    Deltuva, Vytenis Pranas; Jurkienė, Nemira; Kulakienė, Ilona; Bunevičius, Adomas; Matukevičius, Algimantas; Tamašauskas, Arimantas

    2012-01-01

    BACKGROUND AND OBJECTIVE. There is a need for objective semiquantitative indexes for the evaluation of results of single-photon emission tomography (SPECT) in patients with brain glioma. The aim of this study was to validate the total size index (TSI) and total intensity index (TII) based on technetium-99m-methoxyisobutylisonitrile ((99m)Tc-MIBI) SPECT scans to discriminate the patients with high-grade glioma versus low-grade glioma and to evaluate the changes of viable glioma tissue by the means of TSI and TII after surgery and after radiation treatment. MATERIAL AND METHODS. Thirty-two patients (mean age, 55 years [SD, 18]; 20 men) underwent a (99m)Tc-MIBI-SPECT scan before surgery. Of these patients, 27 underwent a postoperative (99m)Tc-MIBI-SPECT scan and 7 patients with grade IV glioma underwent a third (99m)Tc-MIBI-SPECT scan after radiation treatment. TII that corresponds to the area and intensity of tracer uptake and TSI that corresponds to the area of tracer uptake were calculated before surgery, after surgery, and after radiation treatment. RESULTS. The TII and TSI were found to be valid in discriminating the patients with high-grade versus low-grade glioma with optimal cutoff values of 3.0 and 2.5, respectively. Glioma grade correlated with the preoperative TSI score (r=0.76, P<0.001) and preoperative TII score (r=0.64, P<0.001). There was a significant decrease in the TII and TSI after surgery in patients with grade IV glioma. After radiation treatment, there was a significant increase in the TII in patients with grade IV glioma. CONCLUSIONS. TSI and TII were found to be reliable in discriminating the patients with high-grade versus low-grade glioma and allowed for the semiquantitative evaluation of change in viable glioma tissue after surgery and after radiation treatment in patients with grade IV glioma.

  3. A cylindrical SPECT camera with de-centralized readout scheme

    NASA Astrophysics Data System (ADS)

    Habte, F.; Stenström, P.; Rillbert, A.; Bousselham, A.; Bohm, C.; Larsson, S. A.

    2001-09-01

    An optimized brain single photon emission computed tomograph (SPECT) camera is being designed at Stockholm University and Karolinska Hospital. The design goal is to achieve high sensitivity, high-count rate and high spatial resolution. The sensitivity is achieved by using a cylindrical crystal, which gives a closed geometry with large solid angles. A de-centralized readout scheme where only a local environment around the light excitation is readout supports high-count rates. The high resolution is achieved by using an optimized crystal configuration. A 12 mm crystal plus 12 mm light guide combination gave an intrinsic spatial resolution better than 3.5 mm (140 keV) in a prototype system. Simulations show that a modified configuration can improve this value. A cylindrical configuration with a rotating collimator significantly simplifies the mechanical design of the gantry. The data acquisition and control system uses early digitization and subsequent digital signal processing to extract timing and amplitude information, and monitors the position of the collimator. The readout system consists of 12 or more modules each based on programmable logic and a digital signal processor. The modules send data to a PC file server-reconstruction engine via a Firewire (IEEE-1394) network.

  4. Advances in SPECT and PET Hardware.

    PubMed

    Slomka, Piotr J; Pan, Tinsu; Berman, Daniel S; Germano, Guido

    2015-01-01

    There have been significant recent advances in single photon emission computed tomography (SPECT) and positron emission tomography (PET) hardware. Novel collimator designs, such as multi-pinhole and locally focusing collimators arranged in geometries that are optimized for cardiac imaging have been implemented to reduce imaging time and radiation dose. These new collimators have been coupled with solid state photon detectors to further improve image quality and reduce scanner size. The new SPECT scanners demonstrate up to a 7-fold increase in photon sensitivity and up to 2 times improvement in image resolution. Although PET scanners are used primarily for oncological imaging, cardiac imaging can benefit from the improved PET sensitivity of 3D systems without inter-plane septa and implementation of the time-of-flight reconstruction. Additionally, resolution recovery techniques are now implemented by all major PET vendors. These new methods improve image contrast, image resolution, and reduce image noise. Simultaneous PET/magnetic resonance (MR) hybrid systems have been developed. Solid state detectors with avalanche photodiodes or digital silicon photomultipliers have also been utilized in PET. These new detectors allow improved image resolution, higher count rate, as well as a reduced sensitivity to electromagnetic MR fields. Copyright © 2015. Published by Elsevier Inc.

  5. MLEM algorithm adaptation for improved SPECT scintimammography

    NASA Astrophysics Data System (ADS)

    Krol, Andrzej; Feiglin, David H.; Lee, Wei; Kunniyur, Vikram R.; Gangal, Kedar R.; Coman, Ioana L.; Lipson, Edward D.; Karczewski, Deborah A.; Thomas, F. Deaver

    2005-04-01

    Standard MLEM and OSEM algorithms used in SPECT Tc-99m sestamibi scintimammography produce hot-spot artifacts (HSA) at the image support peripheries. We investigated a suitable adaptation of MLEM and OSEM algorithms needed to reduce HSA. Patients with suspicious breast lesions were administered 10 mCi of Tc-99m sestamibi and SPECT scans were acquired for patients in prone position with uncompressed breasts. In addition, to simulate breast lesions, some patients were imaged with a number of breast skin markers each containing 1 mCi of Tc-99m. In order to reduce HSA in reconstruction, we removed from the backprojection step the rays that traverse the periphery of the support region on the way to a detector bin, when their path length through this region was shorter than some critical length. Such very short paths result in a very low projection counts contributed to the detector bin, and consequently to overestimation of the activity in the peripheral voxels in the backprojection step-thus creating HSA. We analyzed the breast-lesion contrast and suppression of HSA in the images reconstructed using standard and modified MLEM and OSEM algorithms vs. critical path length (CPL). For CPL >= 0.01 pixel size, we observed improved breast-lesion contrast and lower noise in the reconstructed images, and a very significant reduction of HSA in the maximum intensity projection (MIP) images.

  6. Quantitative SPECT of uptake of monoclonal antibodies

    SciTech Connect

    DeNardo, G.L.; Macey, D.J.; DeNardo, S.J.; Zhang, C.G.; Custer, T.R.

    1989-01-01

    Absolute quantitation of the distribution of radiolabeled antibodies is important to the efficient conduct of research with these agents and their ultimate use for imaging and treatment, but is formidable because of the unrestricted nature of their distribution within the patient. Planar imaging methods have been developed and provide an adequate approximation of the distribution of radionuclide for many purposes, particularly when there is considerable specificity of targeting. This is not currently the case for antibodies and is unlikely in the future. Single photon emission computed tomography (SPECT) provides potential for greater accuracy because it reduces problems caused by superimposition of tissues and non-target contributions to target counts. SPECT measurement of radionuclide content requires: (1) accurate determination of camera sensitivity; (2) accurate determination of the number of counts in a defined region of interest; (3) correction for attenuation; (4) correction for scatter and septal penetration; (5) accurate measurement of the administered dose; (6) adequate statistics; and (7) accurate definition of tissue mass or volume. The major impediment to each of these requirements is scatter of many types. The magnitude of this problem can be diminished by improvements in tomographic camera design, computer algorithms, and methodological approaches. 34 references.

  7. SPECT-US image fusion and clinical applications

    NASA Astrophysics Data System (ADS)

    Hummel, Johann; Kaar, Marcus; Hoffmann, Rainer; Birkfellner, Wolfgang; Beyer, Thomas; Staudenherz, Anton; Figl, Michael

    2014-03-01

    Because scintigraphic images lack anatomical information, single photon emission tomography (SPECT) and positron emission tomography systems (PET) are combined physically with CTs to compensate for this drawback. In our work, we present a method where the CT is replaced by a 3D ultrasound device. Because in this case a mechanical linkage is not possible, we use an additional optical tracking system (OTS) for spatial correlation of the SPECT or PET information and the US. To enable image fusion between the functional SPECT and the anatomical US we first calibrate the SPECT by means of the optical tracking system. This is done by imaging a phantom with SPECT and scanning the surface of the phantom using a calibrated stylus of the OTS. Applying an iterative closest point (ICP) algorithm results in the transformation between the optical coordinate system and the SPECT coordinate system. When a patient undergoes a SPECT scan, a 3D US image is taken immediately after the scan. Since the scan head of the US is also tracked by the OTS, the transformation between OTS and SPECT can be calculated straight forward. For clinical intervention, the patient is again imaged with the US and a 3D/3D registration between the two US volumes allows to transform the functional information of the SPECT to the current US image in real time. We found a mean distance between the point cloud of the optical stylus and the segmented surface of the phantom of 2.3 mm while the maximum distance was found to be 6.9 mm. The 3D3D registration between the two US images was accomplished with an error of 2.1 mm.

  8. Fabrication of the pinhole aperture for AdaptiSPECT

    PubMed Central

    Kovalsky, Stephen; Kupinski, Matthew A.; Barrett, Harrison H.; Furenlid, Lars R.

    2015-01-01

    AdaptiSPECT is a pre-clinical pinhole SPECT imaging system under final construction at the Center for Gamma-Ray Imaging. The system is designed to be able to autonomously change its imaging configuration. The system comprises 16 detectors mounted on translational stages to move radially away and towards the center of the field-of-view. The system also possesses an adaptive pinhole aperture with multiple collimator diameters and pinhole sizes, as well as the possibility to switch between multiplexed and non-multiplexed imaging configurations. In this paper, we describe the fabrication of the AdaptiSPECT pinhole aperture and its controllers. PMID:26146443

  9. Fractured osteophyte demonstrated on SPECT and computed tomography.

    PubMed

    Spieth, Michael E; Schmitz, Stacey L

    2003-08-01

    ABSTRACT We present an interesting case of a fractured osteophyte causing back pain that was demonstrated both on bone single photon emission computed tomography (SPECT) and computed tomography (CT). The magnetic resonance images, thoracic anterior spine plain radiograph, whole-body bone scan passes, and thoracic spot view were not impressive. Bone SPECT was the impetus for getting the CT scan. The CT scan not only demonstrated the osteophyte but a pseudarthrosis that was probably causing the pain. If it were not for the positive SPECT bone scan, the CT scan would not have been ordered after unimpressive magnetic resonance imaging.

  10. Ventilation/perfusion SPECT or SPECT/CT for lung function imaging in patients with pulmonary emphysema?

    PubMed

    Froeling, Vera; Heimann, Uwe; Huebner, Ralf-Harto; Kroencke, Thomas J; Maurer, Martin H; Doellinger, Felix; Geisel, Dominik; Hamm, Bernd; Brenner, Winfried; Schreiter, Nils F

    2015-07-01

    To evaluate the utility of attenuation correction (AC) of V/P SPECT images for patients with pulmonary emphysema. Twenty-one patients (mean age 67.6 years) with pulmonary emphysema who underwent V/P SPECT/CT were included. AC/non-AC V/P SPECT images were compared visually and semiquantitatively. Visual comparison of AC/non-AC images was based on a 5-point likert scale. Semiquantitative comparison assessed absolute counts per lung (aCpLu) and lung lobe (aCpLo) for AC/non-AC images using software-based analysis; percentage counts (PC = (aCpLo/aCpLu) × 100) were calculated. Correlation between AC/non-AC V/P SPECT images was analyzed using Spearman's rho correlation coefficient; differences were tested for significance with the Wilcoxon rank sum test. Visual analysis revealed high conformity for AC and non-AC V/P SPECT images. Semiquantitative analysis of PC in AC/non-AC images had an excellent correlation and showed no significant differences in perfusion (ρ = 0.986) or ventilation (ρ = 0.979, p = 0.809) SPECT/CT images. AC of V/P SPECT images for lung lobe-based function imaging in patients with pulmonary emphysema do not improve visual or semiquantitative image analysis.

  11. Incremental value of (99m)Tc-HYNIC-TOC SPECT/CT over whole-body planar scintigraphy and SPECT in patients with neuroendocrine tumours.

    PubMed

    Trogrlic, Mate; Težak, Stanko

    2017-06-12

    The aim of this study was to evaluate the additional value of (99m)Tc-HYNIC-TOC SPECT/CT over planar whole-body (WB) scintigraphy and SPECT alone in the detection and accurate localisation of neuroendocrine tumour (NET) lesions. This study included 65 patients with a definitive histological diagnosis of NET prior to scintigraphy. Planar WB scintigraphy, SPECT, and SPECT/CT images were acquired at 4 h post-administration of 670 MBq (99m)Tc-HYNIC-TOC. Additional SPECT images at 10 min after tracer administration were also acquired. Clinical and imaging follow-up findings were considered as the reference standards (minimum follow-up period, 15 months). Patient and lesion-based analyses of the efficacies of the imaging modalities were performed. While 38 patients exhibited metastasis of NETs, 27 presented no evidence of metastasis. Upon patient-based analysis, the sensitivity and specificity of SPECT/CT were found to be 88.9 and 79.3 %, respectively. The diagnostic accuracies of WB scintigraphy, 4h-SPECT, and SPECT/CT were 72.3, 73.8, and 84.6 %, respectively. The area under curve (AUC) value for SPECT/CT (0.84) was the highest, followed by those for 4h-SPECT (0.75) and WB scintigraphy (0.74). The accuracy and AUC values of SPECT/CT were significantly better compared to those of WB scintigraphy (p < 0.001), 10 min-SPECT (p < 0.001), and 4 h-SPECT (p = 0.001). The findings of SPECT/CT led to the change in treatment plan of 11 patients (16.9 %). The sensitivity and diagnostic accuracy of SPECT/CT in the evaluation of NET lesions outperforms planar WB imaging or SPECT alone.

  12. Aperture correction with an asymmetrically trimmed Gaussian weight in SPECT with a fan-beam collimator.

    PubMed

    Kamiya, Ryo; Ogawa, Koichi

    2013-08-01

    The aim of the study is to improve the spatial resolution of SPECT images acquired with a fan-beam collimator. The aperture angle of a hole in the fan-beam collimator depends on the position of the collimator. To correct the aperture effect in an iterative image reconstruction, an asymmetrically trimmed Gaussian weight was used for a model. To confirm the validity of our method, point source phantoms and brain phantom were used in the simulation, and we applied the method to the clinical data. The results of the simulation showed that the spatial resolution of point sources improved from about 6 to 2 pixels full width at half maximum, and the corrected point sources were isotropic. The results of the simulation with the brain phantom showed that our proposed method could improve the spatial resolution of the phantom, and our method was effective for different fan-beam collimators with different focal lengths. The results of clinical data showed that the quality of the reconstructed image was improved with our proposed method. Our proposed aperture correction method with the asymmetrically trimmed Gaussian weighting function was effective in improving the spatial resolution of SPECT images acquired with the fan-beam collimator.

  13. [99mTc-ECD dynamic SPECT in "luxury perfusion" of subacute stroke].

    PubMed

    Ogasawara, K; Fujiwara, S; Yoshimoto, T

    1995-11-01

    To evaluate the cerebral pharmacokinetics of 99mTc-ethyl cysteinate dimer (99mTc-ECD) at blood flow levels beyond the normal range, we investigated "luxury perfusion" in subacute stroke, ictal hyperperfusion in epilepsy and post-decompressive hyperemia in head trauma. All 7 patients showed a hyperactive area on SPECT studies using 99mTc-HM-PAO. 99mTc-ECD static image demonstrated a hyperactive area in both epilepsy and head trauma, and a hypoactive area in "luxury perfusion." On the dynamic SPECT of 99mTc-ECD in both epilepsy and head trauma, brain distribution of the tracer was determined within 2 min. postinjection and remained stable for up to 1 hour; however, "luxury perfusion" area showed a change from initial hyperactivity to late hypoactivity with the passage of time. The time activity curve in "luxury perfusion" area demonstrated a steep decrease of counts/pixel for up to 4-5 minutes postinjection, and a moderate decrease in the following phase. The early wash-out mechanism of 99mTc-ECD from "luxury perfusion" area can be described by a biexponential function including an initial steep decrease representing the rapid loss of the lipophilic complexes which were not metabolized in injured brain tissue.

  14. Advances in CNS Imaging Agents: Focus on PET and SPECT Tracers in Experimental and Clinical Use.

    PubMed

    George, Noble; Gean, Emily G; Nandi, Ayon; Frolov, Boris; Zaidi, Eram; Lee, Ho; Brašić, James R; Wong, Dean F

    2015-04-01

    The physiological functioning of the brain is not well-known in current day medicine and the pathologies of many neuropsychiatric disorders are still not yet fully understood. With our aging population and better life expectancies, it has become imperative to find better biomarkers for disease progression as well as receptor target engagements. In the last decade, these major advances in the field of molecular CNS imaging have been made available with tools such as functional magnetic resonance imaging (fMRI), magnetic resonance spectroscopy (MRS), single photon emission computed tomography (SPECT), and neuroreceptor-targeted positron emission tomography (PET). These tools have given researchers, pharmaceutical companies, and clinical physicians a better method of understanding CNS dysfunctions, and the ability to employ improved therapeutic agents. This review is intended to provide an update on brain imaging agents that are currently used in clinical and translational research toward treatment of CNS disorders. The review begins with amyloid and tau imaging, the former of which has at least three [(18)F] agents that have been recently approved and will soon be available for clinical use for specific indications in the USA and elsewhere. Other prevalent PET and SPECT neurotransmitter system agents, including those newly US FDA-approved imaging agents related to the dopaminergic system, are included. A review of both mature and potentially growing PET imaging agents, including those targeting serotonin and opiate receptor systems, is also provided.

  15. Design and development of MR-compatible SPECT systems for simultaneous SPECT-MR imaging of small animals

    NASA Astrophysics Data System (ADS)

    Tsui, Benjamin M. W.; Hugg, James W.; Xu, Jingyan; Chen, Si; Meier, Dirk; Edelstein, William; El-Sharkawy, Abdel; Wagenaar, Douglas J.; Patt, Bradley E.

    2011-03-01

    We describe a continuing design and development of MR-compatible SPECT systems for simultaneous SPECT-MR imaging of small animals. A first generation prototype SPECT system was designed and constructed to fit inside a MRI system with a gradient bore inner diameter of 12 cm. It consists of 3 angularly offset rings of 8 detectors (1"x1", 16x16 pixels MR-compatible solid-state CZT). A matching 24-pinhole collimator sleeve, made of a tungsten-compound, provides projections from a common FOV of ~25 mm. A birdcage RF coil for MRI data acquisition surrounds the collimator. The SPECT system was tested inside a clinical 3T MRI system. Minimal interference was observed on the simultaneously acquired SPECT and MR images. We developed a sparse-view image reconstruction method based on accurate modeling of the point response function (PRF) of each of the 24 pinholes to provide artifact-free SPECT images. The stationary SPECT system provides relatively low resolution of 3-5 mm but high geometric efficiency of 0.5- 1.2% for fast dynamic acquisition, demonstrated in a SPECT renal kinetics study using Tc-99m DTPA. Based on these results, a second generation prototype MR-compatible SPECT system with an outer diameter of 20 cm that fits inside a mid-sized preclinical MRI system is being developed. It consists of 5 rings of 19 CZT detectors. The larger ring diameter allows the use of optimized multi-pinhole collimator designs, such as high system resolution up to ~1 mm, high geometric efficiency, or lower system resolution without collimator rotation. The anticipated performance of the new system is supported by simulation data.

  16. Real-time landmark-based unrestrained animal tracking system for motion-corrected PET/SPECT imaging

    SciTech Connect

    J.S. Goddard; S.S. Gleason; M.J. Paulus; Stanislaw Majewski; Vladimir Popov; Mark Smith; Andrew Weisenberger; Benjamin Welch; Randolph Wojcik

    2003-08-01

    Oak Ridge National Laboratory (ORNL) and Jefferson Lab and are collaborating to develop a new high-resolution single photon emission tomography (SPECT) instrument to image unrestrained laboratory animals. This technology development will allow functional imaging studies to be performed on the animals without the use of anesthetic agents. This technology development could have eventual clinical applications for performing functional imaging studies on patients that cannot remain still (Parkinson's patients, Alzheimer's patients, small children, etc.) during a PET or SPECT scan. A key component of this new device is the position tracking apparatus. The tracking apparatus is an integral part of the gantry and designed to measure the spatial position of the animal at a rate of 10-15 frames per second with sub-millimeter accuracy. Initial work focuses on brain studies where anesthetic agents or physical restraint can significantly impact physiologic processes.

  17. A novel SPECT-based approach reveals early mechanisms of central and peripheral inflammation after cerebral ischemia

    PubMed Central

    Szigeti, Krisztián; Horváth, Ildikó; Veres, Dániel S; Martinecz, Bernadett; Lénárt, Nikolett; Kovács, Noémi; Bakcsa, Erika; Márta, Alexa; Semjéni, Mariann; Máthé, Domokos; Dénes, Ádám

    2015-01-01

    Inflammation that develops in the brain and peripheral organs after stroke contributes profoundly to poor outcome of patients. However, mechanisms through which inflammation impacts on brain injury and overall outcome are improperly understood, in part because the earliest inflammatory events after brain injury are not revealed by current imaging tools. Here, we show that single-photon emission computed tomography (NanoSPECT/CT Plus) allows visualization of blood brain barrier (BBB) injury after experimental stroke well before changes can be detected with magnetic resonance imaging (MRI). Early 99mTc-DTPA (diethylene triamine pentaacetic acid) signal changes predict infarct development and systemic inflammation preceding experimental stroke leads to very early perfusion deficits and increased BBB injury within 2 hours after the onset of ischemia. Acute brain injury also leads to peripheral inflammation and immunosuppression, which contribute to poor outcome of stroke patients. The SPECT imaging revealed early (within 2 hours) changes in perfusion, barrier function and inflammation in the lungs and the gut after experimental stroke, with good predictive value for the development of histopathologic changes at later time points. Collectively, visualization of early inflammatory changes after stroke could open new translational research avenues to elucidate the interactions between central and peripheral inflammation and to evaluate in vivo ‘multi-system' effects of putative anti-inflammatory treatments. PMID:26219594

  18. Reliability evaluation of I-123 ADAM SPECT imaging using SPM software and AAL ROI methods

    NASA Astrophysics Data System (ADS)

    Yang, Bang-Hung; Tsai, Sung-Yi; Wang, Shyh-Jen; Su, Tung-Ping; Chou, Yuan-Hwa; Chen, Chia-Chieh; Chen, Jyh-Cheng

    2011-08-01

    The level of serotonin was regulated by serotonin transporter (SERT), which is a decisive protein in regulation of serotonin neurotransmission system. Many psychiatric disorders and therapies were also related to concentration of cerebral serotonin. I-123 ADAM was the novel radiopharmaceutical to image SERT in brain. The aim of this study was to measure reliability of SERT densities of healthy volunteers by automated anatomical labeling (AAL) method. Furthermore, we also used statistic parametric mapping (SPM) on a voxel by voxel analysis to find difference of cortex between test and retest of I-123 ADAM single photon emission computed tomography (SPECT) images.Twenty-one healthy volunteers were scanned twice with SPECT at 4 h after intravenous administration of 185 MBq of 123I-ADAM. The image matrix size was 128×128 and pixel size was 3.9 mm. All images were obtained through filtered back-projection (FBP) reconstruction algorithm. Region of interest (ROI) definition was performed based on the AAL brain template in PMOD version 2.95 software package. ROI demarcations were placed on midbrain, pons, striatum, and cerebellum. All images were spatially normalized to the SPECT MNI (Montreal Neurological Institute) templates supplied with SPM2. And each image was transformed into standard stereotactic space, which was matched to the Talairach and Tournoux atlas. Then differences across scans were statistically estimated on a voxel by voxel analysis using paired t-test (population main effect: 2 cond's, 1 scan/cond.), which was applied to compare concentration of SERT between the test and retest cerebral scans.The average of specific uptake ratio (SUR: target/cerebellum-1) of 123I-ADAM binding to SERT in midbrain was 1.78±0.27, pons was 1.21±0.53, and striatum was 0.79±0.13. The cronbach's α of intra-class correlation coefficient (ICC) was 0.92. Besides, there was also no significant statistical finding in cerebral area using SPM2 analysis. This finding might help us

  19. [The development and application in clinical programme of SPECT].

    PubMed

    Sun, Li-ming; Liu, Chen-bin

    2002-11-01

    On the base of original computer software of Elscint Apex 609 RG SPECT, two clinical application programmes are successfully designed for clinical engineers to explore and practise by using the CLIP (The Clinical Interpreter Programming) language.

  20. Performance evaluation of advanced industrial SPECT system with diverging collimator.

    PubMed

    Park, Jang Guen; Jung, Sung-Hee; Kim, Jong Bum; Moon, Jinho; Yeom, Yeon Soo; Kim, Chan Hyeong

    2014-12-01

    An advanced industrial SPECT system with 12-fold-array diverging collimator was developed for flow visualization in industrial reactors and was discussed in the previous study. The present paper describes performance evaluation of the SPECT system under both static- and dynamic- flow conditions. Under static conditions, the movement of radiotracer inside the test reactor was compared with that of color tracer (blue ink) captured with a high-speed camera. The comparison of the reconstructed images obtained with the radiotracer and the SPECT system showed fairly good agreement with video-frames of the color tracer obtained with the camera. Based on the results of the performance evaluation, it is concluded that the SPECT system is suitable for investigation and visualization of flows in industrial flow reactors.

  1. Initial Investigation of Preclinical Integrated SPECT and MR Imaging

    PubMed Central

    Hamamura, Mark J.; Ha, Seunghoon; Roeck, Werner W.; Wagenaar, Douglas J.; Meier, Dirk; Patt, Bradley E.; Nalcioglu, Orhan

    2014-01-01

    Single-photon emission computed tomography (SPECT) can provide specific functional information while magnetic resonance imaging (MRI) can provide high-spatial resolution anatomical information as well as complementary functional information. In this study, we utilized a dual modality SPECT/MRI (MRSPECT) system to investigate the integration of SPECT and MRI for improved image accuracy. The MRSPECT system consisted of a cadmium-zinc-telluride (CZT) nuclear radiation detector interfaced with a specialized radiofrequency (RF) coil that was placed within a whole-body 4 T MRI system. The importance of proper corrections for non-uniform detector sensitivity and Lorentz force effects was demonstrated. MRI data were utilized for attenuation correction (AC) of the nuclear projection data and optimized Wiener filtering of the SPECT reconstruction for improved image accuracy. Finally, simultaneous dual-imaging of a nude mouse was performed to demonstrated the utility of co-registration for accurate localization of a radioactive source. PMID:20082527

  2. [Detection of neurotransmitter interactions with PET and SPECT by pharmacological challenge paradigms].

    PubMed

    Schlösser, R

    2000-01-01

    Functional brain imaging with positron emission tomography (PET) and single photon emission computerized tomography (SPECT) enables the in vivo study of specific neurochemical processes in the context of normal regulatory mechanisms and pathophysiological alterations of the brain. By combining these methods with pharmacological challenge-paradigms, the study of functional interactions of different neurotransmitter systems is possible. This review will present data from animal and healthy volunteer studies as well as first data from investigations in different patient populations with regard to this research direction. Especially, interactions of different neurotransmitter systems with the dopaminergic and the cholinergic system will be discussed. The database acquired so far confirms existing models of neuronal feedback-circuits, and the first clinical results are consistent with the hypothesis of an increased dopaminergic responsivity in schizophrenic patients. These results open up new perspectives for a further evaluation of treatment response predictors from drug-challenge studies and for the development of new drug treatments for neuropsychiatric disorders.

  3. Sequential SPECT/CT imaging starting with stress SPECT in patients with left bundle branch block suspected for coronary artery disease.

    PubMed

    Engbers, Elsemiek M; Timmer, Jorik R; Mouden, Mohamed; Knollema, Siert; Jager, Pieter L; Ottervanger, Jan Paul

    2017-01-01

    To investigate the impact of left bundle branch block (LBBB) on sequential single photon emission computed tomography (SPECT)/ CT imaging starting with stress-first SPECT. Consecutive symptomatic low- to intermediate-risk patients without a history of coronary artery disease (CAD) referred for SPECT/CT were included from an observational registry. If stress SPECT was abnormal, additional rest SPECT and, if feasible, coronary CT angiography (CCTA) were acquired. Of the 5,018 patients, 218 (4.3 %) demonstrated LBBB. Patients with LBBB were slightly older than patients without LBBB (65±12 vs. 61±11 years, p<0.001). Stress SPECT was more frequently abnormal in patients with LBBB (82 % vs. 46 %, p<0.001). After reviewing stress and rest images, SPECT was normal in 43 % of the patients with LBBB, compared to 77 % of the patients without LBBB (p<0.001). Sixty-four of the 124 patients with LBBB and abnormal stress-rest SPECT underwent CCTA (52 %), which could exclude obstructive CAD in 46 of the patients (72 %). Sequential SPECT/CT imaging starting with stress SPECT is not the optimal imaging protocol in patients with LBBB, as the majority of these patients have potentially false-positive stress SPECT. First-line testing using CCTA may be more appropriate in low- to intermediate-risk patients with LBBB. • Stress-first SPECT imaging is attractive if many patients demonstrate normal stress perfusion. • The majority of left bundle branch block patients have abnormal stress-first SPECT. • Coronary CT excluded obstructive CAD in many LBBB patients with abnormal SPECT. • Stress-first SPECT imaging is not the optimal imaging protocol in LBBB patients. • In LBBB patients imaging with initial coronary CT may be more appropriate.

  4. Cervical SPECT Camera for Parathyroid Imaging

    SciTech Connect

    None, None

    2012-08-31

    Primary hyperparathyroidism characterized by one or more enlarged parathyroid glands has become one of the most common endocrine diseases in the world affecting about 1 per 1000 in the United States. Standard treatment is highly invasive exploratory neck surgery called Parathyroidectomy. The surgery has a notable mortality rate because of the close proximity to vital structures. The move to minimally invasive parathyroidectomy is hampered by the lack of high resolution pre-surgical imaging techniques that can accurately localize the parathyroid with respect to surrounding structures. We propose to develop a dedicated ultra-high resolution (~ 1 mm) and high sensitivity (10x conventional camera) cervical scintigraphic imaging device. It will be based on a multiple pinhole-camera SPECT system comprising a novel solid state CZT detector that offers the required performance. The overall system will be configured to fit around the neck and comfortably image a patient.

  5. ACR testing of a dedicated head SPECT unit.

    PubMed

    Sensakovic, William F; Hough, Matthew C; Kimbley, Elizabeth A

    2014-07-08

    Physics testing necessary for program accreditation is rigorously defined by the ACR. This testing is easily applied to most conventional SPECT systems based on gamma camera technology. The inSPira HD is a dedicated head SPECT system based on a rotating dual clamshell design that acquires data in a dual-spiral geometry. The unique geometry and configuration force alterations of the standard ACR physics testing protocol. Various tests, such as intrinsic planar uniformity and/or resolution, do not apply. The Data Spectrum Deluxe Phantom used for conventional SPECT testing cannot fit in the inSPira HD scanner bore, making (currently) unapproved use of the Small Deluxe SPECT Phantom necessary. Matrix size, collimator type, scanning time, reconstruction method, and attenuation correction were all varied from the typically prescribed ACR instructions. Visible spheres, sphere contrast, visible rod groups, uniformity, and root mean square (RMS) noise were measured. The acquired SPECT images surpassed the minimum ACR requirements for both spatial resolution (9.5 mm spheres resolved) and contrast (6.4 mm rod groups resolved). Sphere contrast was generally high. Integral uniformity was 4% and RMS noise was 1.7%. Noise appeared more correlated than in images from a conventional SPECT scanner. Attenuation-corrected images produced from direct CT scanning of the phantom and a manufacturer supplied model of the phantom demonstrated negligible differences.

  6. Review and current status of SPECT scatter correction

    NASA Astrophysics Data System (ADS)

    Hutton, Brian F.; Buvat, Irène; Beekman, Freek J.

    2011-07-01

    Detection of scattered gamma quanta degrades image contrast and quantitative accuracy of single-photon emission computed tomography (SPECT) imaging. This paper reviews methods to characterize and model scatter in SPECT and correct for its image degrading effects, both for clinical and small animal SPECT. Traditionally scatter correction methods were limited in accuracy, noise properties and/or generality and were not very widely applied. For small animal SPECT, these approximate methods of correction are often sufficient since the fraction of detected scattered photons is small. This contrasts with patient imaging where better accuracy can lead to significant improvement of image quality. As a result, over the last two decades, several new and improved scatter correction methods have been developed, although often at the cost of increased complexity and computation time. In concert with (i) the increasing number of energy windows on modern SPECT systems and (ii) excellent attenuation maps provided in SPECT/CT, some of these methods give new opportunities to remove degrading effects of scatter in both standard and complex situations and therefore are a gateway to highly quantitative single- and multi-tracer molecular imaging with improved noise properties. Widespread implementation of such scatter correction methods, however, still requires significant effort.

  7. Diagnostic role of (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging for early and atypical bone metastases.

    PubMed

    Chen, Xiao-Liang; Li, Qian; Cao, Lin; Jiang, Shi-Xi

    2014-01-01

    The bone metastasis appeared early before the bone imaging for most of the above patients. (99)Tc(m)-MDP ((99)Tc(m) marked methylene diphosphonate) bone imaging could diagnosis the bone metastasis with highly sensitivity, but with lower specificity. The aim of this study is to explore the diagnostic value of (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging for the early period atypical bone metastases. 15 to 30 mCi (99)Tc(m)-MDP was intravenously injected to the 34 malignant patients diagnosed as doubtful early bone metastases. SPECT, CT and SPECT/CT images were captured and analyzed consequently. For the patients diagnosed as early period atypical bone metastases by SPECT/CT, combining the SPECT/CT and MRI together as the SPECT/MRI integrated image. The obtained SPECT/MRI image was analyzed and compared with the pathogenic results of patients. The results indicated that 34 early period doubtful metastatic focus, including 34 SPECT positive focus, 17 focus without special changes by using CT method, 11 bone metastases focus by using SPECT/CT method, 23 doubtful bone metastases focus, 8 doubtful bone metastases focus, 14 doubtful bone metastases focus and 2 focus without clear image. Totally, SPECT/CT combined with SPECT/MRI method diagnosed 30 bone metastatic focus and 4 doubtfully metastatic focus. In conclusion, (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging shows a higher diagnostic value for the early period bone metastases, which also enhances the diagnostic accuracy rate.

  8. A Multimodal Imaging Protocol, (123)I/(99)Tc-Sestamibi, SPECT, and SPECT/CT, in Primary Hyperparathyroidism Adds Limited Benefit for Preoperative Localization.

    PubMed

    Lee, Grace S; McKenzie, Travis J; Mullan, Brian P; Farley, David R; Thompson, Geoffrey B; Richards, Melanie L

    2016-03-01

    Focused parathyroidectomy in primary hyperparathyroidism (1°HPT) is possible with accurate preoperative localization and intraoperative PTH monitoring (IOPTH). The added benefit of multimodal imaging techniques for operative success is unknown. Patients with 1°HPT, who underwent parathyroidectomy in 2012-2014 at a single institution, were retrospectively reviewed. Only the patients who underwent the standardized multimodal imaging workup consisting of (123)I/(99)Tc-sestamibi subtraction scintigraphy, SPECT, and SPECT/CT were assessed. Of 360 patients who were identified, a curative operation was performed in 96%, using pre-operative imaging and IOPTH. Imaging analysis showed that (123)I/(99)Tc-sestamibi had a sensitivity of 86% (95% CI 82-90%), positive predictive value (PPV) 93%, and accuracy 81%, based on correct lateralization. SPECT had a sensitivity of 77% (95% CI 72-82%), PPV 92% and accuracy 72%. SPECT/CT had a sensitivity of 75% (95% CI 70-80%), PPV of 94%, and accuracy 71%. There were 3 of 45 (7%) patients with negative sestamibi imaging that had an accurate SPECT and SPECT/CT. Of 312 patients (87%) with positive uptake on sestamibi (93% true positive, 7% false positive), concordant findings were present in 86% SPECT and 84% SPECT/CT. In cases where imaging modalities were discordant, but at least one method was true-positive, (123)I/(99)Tc-sestamibi was significantly better than both SPECT and SPECT/CT (p < 0.001). The inclusion of SPECT and SPECT/CT in 1°HPT imaging protocol increases patient cost up to 2.4-fold. (123)I/(99)Tc-sestamibi subtraction imaging is highly sensitive for preoperative localization in 1°HPT. SPECT and SPECT/CT are commonly concordant with (123)I/(99)Tc-sestamibi and rarely increase the sensitivity. Routine inclusion of multimodality imaging technique adds minimal clinical benefit but increases cost to patient in high-volume setting.

  9. Imaging the neurobiological substrate of atypical depression by SPECT.

    PubMed

    Pagani, Marco; Salmaso, Dario; Nardo, Davide; Jonsson, Cathrine; Jacobsson, Hans; Larsson, Stig A; Gardner, Ann

    2007-01-01

    Neurobiological abnormalities underlying atypical depression have previously been suggested. The purpose of this study was to explore differences at functional brain imaging between depressed patients with and without atypical features and healthy controls. Twenty-three out-patients with chronic depressive disorder recruited from a service for patients with audiological symptoms were investigated. Eleven fulfilled the DSM-IV criteria for atypical depression (mood reactivity and at least two of the following: weight gain, hypersomnia, leaden paralysis and interpersonal rejection sensitivity). Twenty-three healthy subjects served as controls. Voxel-based analysis was applied to explore differences in (99m)Tc-HMPAO uptake between groups. Patients in the atypical group had a higher prevalence of bilateral hearing impairment and higher depression and somatic distress ratings at the time of SPECT. Significantly higher tracer uptake was found bilaterally in the atypical group as compared with the non-atypicals in the sensorimotor (Brodmann areas, BA1-3) and premotor cortex in the superior frontal gyri (BA6), in the middle frontal cortex (BA8), in the parietal associative cortex (BA5, BA7) and in the inferior parietal lobule (BA40). Significantly lower tracer distribution was found in the right hemisphere in the non-atypicals compared with the controls in BA6, BA8, BA44, BA45 and BA46 in the frontal cortex, in the orbito-frontal cortex (BA11, BA47), in the postcentral parietal cortex (BA2) and in the multimodal association parietal cortex (BA40). The differences found between atypical and non-atypical depressed patients suggest different neurobiological substrates in these patient groups. The putative links with the clinical features of atypical depression are discussed. These findings encourage the use of functional neuroimaging in psychiatric disorders.

  10. Parametric Cerebrovascular Reserve Images Using Acetazolamide (99m)Tc-HMPAO SPECT: A Feasibility Study of Quantitative Assessment.

    PubMed

    Choi, Hongyoon; Yoo, Min Young; Cheon, Gi Jeong; Kang, Keon Wook; Chung, June-Key; Lee, Dong Soo

    2013-09-01

    Basal/acetazolamide stress (99m)Tc-HMPAO single-photon emission computed tomography (SPECT) has been widely used for evaluation of hemodynamics; however, qualitative and subjective visual assessment of cerebrovascular reserve (CVR) has been performed in clinical settings. The aim of this study was to generate parametric CVR images and evaluate its feasibility of quantification. Basal/acetazolamide stress (99m)Tc-HMPAO SPECT data from 17 patients who underwent bypass surgery or percutaneous transluminal angioplasty were used. Spatial normalization was performed and parametric CVR images were generated using relative CVR (rCVR) of each voxel proportional to CVR of the whole brain. Binary parametric maps to show area of relatively reduced CVR were generated also using threshold of rCVR < 90 %. We calculated rCVR of internal carotid artery (ICA) using the parametric CVR images and probabilistic maps for ICA territory. Pre- and postprocedural parametric CVR images were obtained and quantitative rCVRs were compared. The rCVRs were evaluated according to visual grades for regional decreased CVR. Postprocedural rCVR obtained from parametric CVR images increased significantly from preprocedural rCVR. The rCVR was significantly correlated with visual grades of reduced CVR for each side of ICA territories. We generated parametric CVR images for basal/acetazolamide stress (99m)Tc-HMPAO SPECT. As a quantitative measurement, rCVR obtained from the parametric image was feasibly assessed hemodynamic abnormalities with preserved anatomical information.

  11. Recent and future evolutions in NeuroSPECT with particular emphasis on the synergistic use and fusion of imaging modalities.

    PubMed

    d'Asseler, Y M; Koole, M; Lemahieu, I; Achten, E; Boon, P; De Deyn, P P; Dierckx, R A

    1997-09-01

    Recent and future evolutions in neuroSPECT apply to radiopharmaceuticals techniques and the synergistic use of different imaging modalities in the work-up of neurological disorders. The introduction of Technetium labelled perfusion tracers, which could pass the intact blood-brain barrier, together with the implementation of the tomographic principle, by making the conventional gamma camera rotating, enabled estimation of regional cerebral blood flow and indirectly of local brain metabolism. In addition at present Thallium-201 and Tc-99m sestaMIBI allow functional detection of viable tumor tissue, without interference from previous surgery or radiotherapy as seen using CT-scan or MRI. In neurology this has led to the recognition of SPECT by the American Academy of Neurology (Therapeutics and technology subcommittee) as an established or promising tool in major neurological disorders such as dementia, stroke and epilepsy, while other domains such as brain oncology are considered investigational. With regard to radiopharmaceuticals, recent evolutions mainly include the development of mostly Iodine-123 labelled receptor ligands, some of which are already commercially available. For instrumentation advances consist e.g. of multidetector systems equipped with fanbeam collimators, attenuation and scatter correction or coincidence detection. Given the present role for nuclear neurology it may be expected that these additional radiopharmaceutical and technical innovations will continue to stimulate the development of SPECT of the brain. The synergistic use of several imaging techniques such as CT, (functional) MRI, source imaging, SPECT and PET represents a multimodal holistic approach to probe cerebral functions for research and clinical purposes. Clinical indications, in which this synergistic use is illustrated include e.g. support of the clinical diagnosis of dementia of the Alzheimer type, presurgical ictal detection of seizure focus, detection of acute ischemia and

  12. IQ-SPECT for thallium-201 myocardial perfusion imaging: effect of normal databases on quantification.

    PubMed

    Konishi, Takahiro; Nakajima, Kenichi; Okuda, Koichi; Yoneyama, Hiroto; Matsuo, Shinro; Shibutani, Takayuki; Onoguchi, Masahisa; Kinuya, Seigo

    2017-07-01

    Although IQ-single-photon emission computed tomography (SPECT) provides rapid acquisition and attenuation-corrected images, the unique technology may create characteristic distribution different from the conventional imaging. This study aimed to compare the diagnostic performance of IQ-SPECT using Japanese normal databases (NDBs) with that of the conventional SPECT for thallium-201 ((201)Tl) myocardial perfusion imaging (MPI). A total of 36 patients underwent 1-day (201)Tl adenosine stress-rest MPI. Images were acquired with IQ-SPECT at approximately one-quarter of the standard time of conventional SPECT. Projection data acquired with the IQ-SPECT system were reconstructed via an ordered subset conjugate gradient minimizer method with or without scatter and attenuation correction (SCAC). Projection data obtained using the conventional SPECT were reconstructed via a filtered back projection method without SCAC. The summed stress score (SSS) was calculated using NDBs created by the Japanese Society of Nuclear Medicine working group, and scores were compared between IQ-SPECT and conventional SPECT using the acquisition condition-matched NDBs. The diagnostic performance of the methods for the detection of coronary artery disease was also compared. SSSs were 6.6 ± 8.2 for the conventional SPECT, 6.6 ± 9.4 for IQ-SPECT without SCAC, and 6.5 ± 9.7 for IQ-SPECT with SCAC (p = n.s. for each comparison). The SSS showed a strong positive correlation between conventional SPECT and IQ-SPECT (r = 0.921 and p < 0.0001), and the correlation between IQ-SPECT with and without SCAC was also good (r = 0.907 and p < 0.0001). Regarding diagnostic performance, the sensitivity, specificity, and accuracy were 80.8, 78.9, and 79.4%, respectively, for the conventional SPECT; 80.8, 80.3, and 82.0%, respectively, for IQ-SPECT without SCAC; and 88.5, 86.8, and 87.3%, respectively, for IQ-SPECT with SCAC, respectively. The area under the curve obtained via receiver operating

  13. Regional cerebral blood flow assessed by single photon emission computed tomography (SPECT) in dogs with congenital portosystemic shunt and hepatic encephalopathy.

    PubMed

    Or, Matan; Peremans, Kathelijne; Martlé, Valentine; Vandermeulen, Eva; Bosmans, Tim; Devriendt, Nausikaa; de Rooster, Hilde

    2017-02-01

    Regional cerebral blood flow (rCBF) in eight dogs with congenital portosystemic shunt (PSS) and hepatic encephalopathy (HE) was compared with rCBF in eight healthy control dogs using single photon emission computed tomography (SPECT) with a (99m)technetium-hexamethylpropylene amine oxime ((99m)Tc-HMPAO) tracer. SPECT scans were abnormal in all PSS dogs. Compared to the control group, rCBF in PSS dogs was significantly decreased in the temporal lobes and increased in the subcortical (thalamic and striatal) area. Brain perfusion imaging alterations observed in the dogs with PSS and HE are similar to those in human patients with HE. These findings suggest that dogs with HE and PSS have altered perfusion of mainly the subcortical and the temporal regions of the brain.

  14. Extensive brain infarction involving deep structures during an acetazolamide-challenged single-photon emission computed tomography scan in a patient with moyamoya disease.

    PubMed

    Chong, Sangjoon; Park, June Dong; Chae, Jong Hee; Cheon, Jung-Eun; Kim, Seung-Ki; Phi, Ji Hoon; Lee, Ji Yeoun; Paeng, Jin Chul; Wang, Kyu-Chang

    2017-07-08

    Acetazolamide-challenged brain single-photon emission computed tomography (SPECT) is used for the evaluation of cerebral perfusion in cerebrovascular diseases including moyamoya disease (MMD). Not a few patients experience adverse side effects during the acetazolamide-challenged brain SPECT, but most of the symptoms are mild and transient. To our knowledge, this is the first case report of severe brain infarction leading to death during the examination of an acetazolamide-challenged brain SPECT in a patient with MMD. An 11-year-old girl who had been diagnosed of MMD demonstrated sudden tonic movement during an acetazolamide-challenged brain SPECT as the preoperative examination for the second surgery. She had not experienced any adverse effect during the previous SPECT study and her first indirect bypass surgery on both left side and bifrontal area was uneventful. After she had seizures twice, she became unconscious and her pupils were dilated and fixed. Acute infarction involving bilateral occipital lobes, thalami, brainstem, and cerebellum was observed on brain magnetic resonance images which led to brain death. We report a mortality case of patient with MMD after the administration of acetazolamide during the examination of brain SPECT that was accompanied by an extensive acute infarction involving the bilateral occipital lobes and thalami, brainstem, and cerebellum. Physicians should be aware of this rare but serious complication.

  15. SPECT determination of regional cerebral blood flow in hypertensive patients before and after clonidine

    SciTech Connect

    Devous, M.D.; Reed, W.G.; Chehabi, H.H.; Bonte, F.J.

    1985-05-01

    Regional cerebral blood flow (rCBF) was determined by SPECT of 133-Xe inert gas washout in 18 hypertensive patients (PTS) upon admission and after treatment with oral clonidine (CL, 0.2 mg, then 0.1 mg/hr until diastolic pressure reached 105 mm Hg or fell by 30 mm Hg). CL reduced mean arterial pressure (MAP) from 160 (200/140) to 133 (150/100) mm Hg over 4-6 hr. RCBF was quantitated in 14 gray matter regions from cross-sectional images and analyzed for differences from normal controls and changes with CL. Initial rCBF was lower in HI PTS than in either normal controls of LO PTS in all brain regions. CL lowered MAP in HI PTS by 52 +- 15 mm Hg and caused reduction in all gray matter regions except right frontal and right temporal (mean reduction 5 +- 2 ml/min/100 g, rho<.05). RCBF images were also evaluated by two trained observers for initial regional defects and for changes with CL. LO PTS were more likely to have defects in rCBF images at rest which would resolve with CL. HI PTS frequently had normal images at rest and developed defects with CL. In summary, the study suggests that SPECT may be useful in detecting rCBF abnormalities in hypertensive PTS at rest and following reductions in MAP.

  16. Altered SPECT 123I-iomazenil Binding in the Cingulate Cortex of Children with Anorexia Nervosa

    PubMed Central

    Nagamitsu, Shinichiro; Sakurai, Rieko; Matsuoka, Michiko; Chiba, Hiromi; Ozono, Shuichi; Tanigawa, Hitoshi; Yamashita, Yushiro; Kaida, Hayato; Ishibashi, Masatoshi; Kakuma, Tatsuki; Croarkin, Paul E.; Matsuishi, Toyojiro

    2016-01-01

    Several lines of evidence suggest that anxiety plays a key role in the development and maintenance of anorexia nervosa (AN) in children. The purpose of this study was to examine cortical GABA(A)-benzodiazepine receptor binding before and after treatment in children beginning intensive AN treatment. Brain single-photon emission computed tomography (SPECT) measurements using 123I-iomazenil, which binds to GABA(A)-benzodiazepine receptors, was performed in 26 participants with AN who were enrolled in a multimodal treatment program. Sixteen of the 26 participants underwent a repeat SPECT scan immediately before discharge at conclusion of the intensive treatment program. Eating behavior and mood disturbances were assessed using Eating Attitudes Test with 26 items (EAT-26) and the short form of the Profile of Mood States (POMS). Clinical outcome scores were evaluated after a 1-year period. We examined association between relative iomazenil-binding activity in cortical regions of interest and psychometric profiles and determined which psychometric profiles show interaction effects with brain regions. Further, we determined if binding activity could predict clinical outcome and treatment changes. Higher EAT-26 scores were significantly associated with lower iomazenil-binding activity in the anterior and posterior cingulate cortex. Higher POMS subscale scores were significantly associated with lower iomazenil-binding activity in the left frontal, parietal cortex, and posterior cingulate cortex (PCC). “Depression–Dejection” and “Confusion” POMS subscale scores, and total POMS score showed interaction effects with brain regions in iomazenil-binding activity. Decreased binding in the anterior cingulate cortex and left parietal cortex was associated with poor clinical outcomes. Relative binding increases throughout the PCC and occipital gyrus were observed after weight gain in children with AN. These findings suggest that cortical GABAergic receptor binding is altered

  17. Assessment of demented patients by dynamic SPECT of inhaled xenon-133

    SciTech Connect

    Komatani, A.; Yamaguchi, K.; Sugai, Y.; Takanashi, T.; Kera, M.; Shinohara, M.; Kawakatsu, S.

    1988-10-01

    We studied the potential for using dynamic single photon emission computed tomography of inhaled xenon-133 (/sup 133/Xe) gas in the assessment of demented patients. An advanced ring-type single photon emission computed tomography (SPECT) HEADTOME with improved spatial resolution (15 mm in full width at half maximum (FWHM)) was used for tomographic measurement of regional cerebral blood flow (rCBF). All 34 patients underwent a detailed psychiatric examination and x-ray computed tomography scan, and matched research criteria for Alzheimer's disease (n = 13), senile dementia of the Alzheimer type (n = 9), or multi-infarct dementia (n = 12). In comparison with a senile control group (n = 7), mean CBF of both the whole brain and the temporo-parietal region was significantly less in the Alzheimer's disease and senile dementia Alzheimer type groups, but no significant difference was seen between the senile control group and multi-infarct dementia group. The correlation was 0.72 (p less than 0.004) between the mean CBF of the whole brain and the score of Hasegawa's Dementia Scale, and 0.94 (p less than 0.0001) between rCBF of the temporo-parietal region and the scale in Alzheimer's disease. In the senile dementia Alzheimer type group, the correlations were 0.77 (p less than 0.01) and 0.83 (p less than 0.004) respectively. No significant correlations were found in the multi-infarct dementia group. A temporo-parietal reduction in the distribution of the rCBF characteristic in the Alzheimer's disease group and a patchy whole brain reduction characteristic in the multi-infarct dementia group was detected. The ability of our improved SPECT to provide both quantitative measurement of rCBF and characteristic rCBF distribution patterns, makes it a promising tool for research or routine examination of demented patients.

  18. High resolution SPECT with [99mTc]-d,l-HMPAO in normal pressure hydrocephalus before and after shunt operation.

    PubMed Central

    Waldemar, G; Schmidt, J F; Delecluse, F; Andersen, A R; Gjerris, F; Paulson, O B

    1993-01-01

    Cranial CT and high resolution measurements of regional cerebral blood flow (rCBF) with brain dedicated single photon emission computer tomography (SPECT) and [99mTc]-d,l-hexamethylpropyleneamine oxime ([99mTc]-d,l-HMPAO) were performed before and after shunt operation in 14 consecutive patients with dementia and normal pressure hydrocephalus (NPH). When compared with a control group of 14 age matched healthy volunteers, the group of NPH patients was characterised by an enlarged subcortical low-flow region, significantly reduced rCBF and enhanced side-to-side asymmetry of rCBF in the central white matter, and enhanced side-to-side asymmetry in the inferior and mid-temporal cortex. Global CBF was normal. Shunt operation reduced the mean area of the ventricles on CT and of the subcortical low-flow region on SPECT. Global CBF was unchanged. All 14 patients had an abnormal pre-shunt rCBF pattern with enlargement of the subcortical low flow region, focal cortical blood flow deficits, or both. Shunt operation improved the clinical status in 11 patients, and the area of the subcortical low flow region correctly classified 3/3 unimproved and 10/11 improved patients. Shunt operation normalised or reduced the area of the subcortical low flow region in nine of 10 patients. It is concluded that SPECT with [99mTc]-d,l-HMPAO is a useful supplement in the diagnosis of NPH versus normal ageing, and that SPECT may help to identify patients not likely to benefit clinically from surgery. Images PMID:8509780

  19. Simulation of the expected performance of INSERT: A new multi-modality SPECT/MRI system for preclinical and clinical imaging

    NASA Astrophysics Data System (ADS)

    Busca, P.; Fiorini, C.; Butt, A. D.; Occhipinti, M.; Peloso, R.; Quaglia, R.; Schembari, F.; Trigilio, P.; Nemeth, G.; Major, P.; Erlandsson, K.; Hutton, B. F.

    2014-01-01

    A new multi-modality imaging tool is under development in the framework of the INSERT (INtegrated SPECT/MRI for Enhanced Stratification in Radio-chemo Therapy) project, supported by the European Community. The final goal is to develop a custom SPECT apparatus, that can be used as an insert for commercially available MRI systems such as 3 T MRI with 59 cm bore diameter. INSERT is expected to offer more effective and earlier diagnosis with potentially better outcome in survival for the treatment of brain tumors, primarily glioma. Two SPECT prototypes will be developed, one dedicated to preclinical imaging, the second one dedicated to clinical imaging. The basic building block of the SPECT detector ring is a small 5 cm×5 cm gamma camera, based on the well-established Anger architecture with a continuous scintillator readout by an array of silicon photodetectors. Silicon Drift Detectors (SDDs) and Silicon PhotoMultipliers (SiPM) are being considered as possible scintillator readout, considering that the detector choice plays a predominant role for the final performance of the system, such as energy and spatial resolution, as well as the useful field of view of the camera. Both solutions are therefore under study to evaluate their performances in terms of field of view (FOV), spatial and energy resolution. Preliminary simulations for both the preclinical and clinical systems have been carried out to evaluate resolution and sensitivity.

  20. MediSPECT: Single photon emission computed tomography system for small field of view small animal imaging based on a CdTe hybrid pixel detector

    NASA Astrophysics Data System (ADS)

    Accorsi, R.; Autiero, M.; Celentano, L.; Chmeissani, M.; Cozzolino, R.; Curion, A. S.; Frallicciardi, P.; Laccetti, P.; Lanza, R. C.; Lauria, A.; Maiorino, M.; Marotta, M.; Mettivier, G.; Montesi, M. C.; Riccio, P.; Roberti, G.; Russo, P.

    2007-02-01

    We describe MediSPECT, a new scanner developed at University and INFN Napoli, for SPECT studies on small animals with a small field of view (FOV) and high spatial resolution. The CdTe pixel detector (a 256×256 matrix of 55 μm square pixels) operating in single photon counting for detection of gamma-rays with low and medium energy (e.g. 125I, 27-35 keV, 99mTc, 140 keV), is bump bonded to the Medipix2 readout chip. The FOV of the MediSPECT scanner with a coded aperture mask collimator ranges from 6.3 mm (system spatial resolution 110 μm at 27-35 keV) to 24.3 mm. With a 0.30 mm pinhole the FOV ranges from 2.4 to 29 mm (where the system spatial resolution is 1.0 mm at 27-35 keV and 2.0 mm at 140 keV). MediSPECT will be used for in vivo imaging of small organs or tissue structures in mouse, e.g., brain, thyroid, heart or tumor.

  1. Recent developments and future prospects of SPECT myocardial perfusion imaging.

    PubMed

    Zaman, Maseeh Uz; Hashmi, Ibrahim; Fatima, Nosheen

    2010-10-01

    Myocardial perfusion SPECT imaging is the most commonly performed functional imaging for assessment of coronary artery disease. High diagnostic accuracy and incremental prognostic value are the major benefits while suboptimal spatial resolution and significant radiation exposure are the main limitations. Its ability to detect hemodynamic significance of lesions seen on multidetector CT angiogram (MDCTA) has paved the path for a successful marriage between anatomical and functional imaging modalities in the form of hybrid SPECT/MDCTA system. In recent years, there have been enormous efforts by industry and academia to develop new SPECT imaging systems with better sensitivity, resolution, compact design and new reconstruction algorithms with ability to improve image quality and resolution. Furthermore, expected arrival of Tc-99m-labeled deoxyglucose in next few years would further strengthen the role of SPECT in imaging hibernating myocardium. In view of these developments, it seems that SPECT would enjoy its pivotal role in spite of major threat to be replaced by fluorine-18-labeled positron emission tomography perfusion and glucose metabolism imaging agents.

  2. Performance Evaluation of a Bedside Cardiac SPECT System

    NASA Astrophysics Data System (ADS)

    Studenski, Matthew T.; Gilland, David R.; Parker, Jason G.; Hammond, B.; Majewski, Stan; Weisenberger, Andrew G.; Popov, Vladimir

    2009-06-01

    This paper reports on the initial performance evaluation of a bedside cardiac PET/SPECT system. The system was designed to move within a hospital to image critically-ill patients, for example, those in intensive care unit (ICU) or emergency room settings, who cannot easily be transported to a conventional SPECT or PET facility. The system uses two compact (25 cm times 25 cm) detectors with pixilated NaI crystals and position sensitive PMTs. The performance is evaluated for both 140 keV (Tc-99m) and 511 keV (F-18) emitters with the system operating in single photon counting (SPECT) mode. The imaging performance metrics for both 140 keV and 511 keV included intrinsic energy resolution, spatial resolution (intrinsic, system, and reconstructed SPECT), detection sensitivity, count rate capability, and uniformity. Results demonstrated an intrinsic energy resolution of 31% at 140 keV and 23% at 511 keV, a planar intrinsic spatial resolution of 5.6 mm full width half-maximum (FWHM) at 140 keV and 6.3 mm FWHM at 511 keV, and a sensitivity of 4.15 countsmiddotmuCi-1 ldr s-1 at 140 keV and 0.67 counts ldr muCi-1 ldr s-1 at 511 keV. To further the study, a SPECT acquisition using a dynamic cardiac phantom was performed, and the resulting reconstructed images are presented.

  3. Multimodality tomographic scintimammography with PET, PECI, and SPECT: initial evaluation

    NASA Astrophysics Data System (ADS)

    Krol, Andrzej; Feiglin, David H.; Thomas, Frank D.; Hellwig, Bradford J.; Gagne, George M.

    2002-04-01

    We compared tomographic scintimammography performed using single photon emission computed tomography (SPECT), positron emission coincidence imaging (PECI) and positron emission tomography (PET). A female thorax phantom was used. Activities of the myocardium, thorax and breasts were adjusted to emulate the count rate observed with patients. Hollow plastic spheres, imitating hot lesions (1.5-20ml), filled with radioactive saline were inserted in the center of each breast. Specific activities of internal organs were adjusted to emulate the count rate observed with patients. SPECT data were acquired with Tc-99m using gamma cameras with NaI(Tl) detectors. A modified FBP (CODE) reconstruction algorithm was used to render SPECT tomographic images. PECI (Siemens E.CAM with NaI(Tl)) and PET (GE Advance with BGO) data were acquired using F-18 FDG. Vendor supplied reconstruction algorithms were used. The reconstructed hot lesions contrast and resolution were investigated. Image quality obtained can be ranked as follows: (1) PET(BGO), (2) PECI(NaI), (3) SPECT(NaI) In conclusion, assuming comparable uptake values of Tc-99m-sestamibi and F-18 FDG, PET seems to be a superior methodology in visualization of breast lesion as compared to SPECT and PECI. All these tomographic methods appear to be promising adjunct to x-ray mammography in difficult to interpret cases.

  4. Enhancing the utility of prostascint SPECT scans for patient management.

    PubMed

    Noz, Marilyn E; Chung, Grace; Lee, Benjamin Y; Maguire, Gerald Q; DeWyngaert, J Keith; Doshi, Jay V; Kramer, Elissa L; Murphy-Walcott, Antoinette D; Zeleznik, Michael P; Kwak, Noeun G

    2006-04-01

    This project investigated reducing the artifact content of In-ill ProstaScint SPECT scans for use in treatment planning and management. Forty-one patients who had undergone CT or MRI scans and simultaneous Tc-99m RBC/In-111 ProstaScint SPECT scans were included. SPECT volume sets, reconstructed using Ordered Set-Expectation Maximum (OS-EM) were compared against those reconstructed with standard Filtered Back projection (FBP). Bladder activity in Tc-99m scans was suppressed within an ellipsoidal volume. Tc-99m voxel values were subtracted from the corresponding In-111 after scaling based on peak activity within the descending aorta. The SPECT volume data sets were merged with the CT or MRI scans before and after processing. Volume merging, based both on visual assessment and statistical evaluation, was not affected. Thus iterative reconstruction together with bladder suppression and blood pool subtraction may improve the interpretation and utility of ProstaScint SPECT scans for patient management.

  5. Dynamic In Vivo SPECT Imaging of Neural Stem Cells Functionalized with Radiolabeled Nanoparticles for Tracking of Glioblastoma.

    PubMed

    Cheng, Shih-Hsun; Yu, Dou; Tsai, Hsiu-Ming; Morshed, Ramin A; Kanojia, Deepak; Lo, Leu-Wei; Leoni, Lara; Govind, Yureve; Zhang, Lingjiao; Aboody, Karen S; Lesniak, Maciej S; Chen, Chin-Tu; Balyasnikova, Irina V

    2016-02-01

    There is strong clinical interest in using neural stem cells (NSCs) as carriers for targeted delivery of therapeutics to glioblastoma. Multimodal dynamic in vivo imaging of NSC behaviors in the brain is necessary for developing such tailored therapies; however, such technology is lacking. Here we report a novel strategy for mesoporous silica nanoparticle (MSN)-facilitated NSC tracking in the brain via SPECT. (111)In was conjugated to MSNs, taking advantage of the large surface area of their unique porous feature. A series of nanomaterial characterization assays was performed to assess the modified MSN. Loading efficiency and viability of NSCs with (111)In-MSN complex were optimized. Radiolabeled NSCs were administered to glioma-bearing mice via either intracranial or systemic injection. SPECT imaging and bioluminescence imaging were performed daily up to 48 h after NSC injection. Histology and immunocytochemistry were used to confirm the findings. (111)In-MSN complexes show minimal toxicity to NSCs and robust in vitro and in vivo stability. Phantom studies demonstrate feasibility of this platform for NSC imaging. Of significance, we discovered that decayed (111)In-MSN complexes exhibit strong fluorescent profiles in preloaded NSCs, allowing for ex vivo validation of the in vivo data. In vivo, SPECT visualizes actively migrating NSCs toward glioma xenografts in real time after both intracranial and systemic administrations. This is in agreement with bioluminescence live imaging, confocal microscopy, and histology. These advancements warrant further development and integration of this technology with MRI for multimodal noninvasive tracking of therapeutic NSCs toward various brain malignancies. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  6. Synthesis, radiolabeling, and baboon SPECT imaging of 2β-carbomethoxy-3β-(3′-[123I]iodophenyl)tropane ([123I]YP256) as a serotonin transporter radiotracer.([123I]YP256) a potential serotonin transporter radiotracer)

    PubMed Central

    Bois, Frederic; Baldwin, Ronald M.; Amici, Louis; Al-Tikriti, Mohammed S.; Kula, Nora; Baldessarini, Ross; Innis, Robert B.; Staley, Julie K.; Tamagnan., Gilles D.

    2008-01-01

    To develop a potential SPECT probe to evaluate the integrity of the serotoninergic system (5-HTT) whose dysfunction is linked to several disease conditions such as Parkinson’s, Alzheimer’s diseases and depression, we report the synthesis, radiolabeling and in vivo baboon imaging of 2β-carbomethoxy-3β-(3′-[123I]iodophenyl) tropane (YP256, 6). The radiolabeling was performed by iododestannylation using sodium [123I]iodide and peracetic acid. Although the ligand displayed high selectivity for 5-HTT over dopamine transporter (DAT) in vitro, SPECT imaging in baboons did not reveal selective 5-HTT accumulation in brain in vivo. PMID:18158943

  7. A SPECT imager with synthetic collimation

    NASA Astrophysics Data System (ADS)

    Havelin, Ronan J.; Miller, Brian W.; Barrett, Harrison H.; Furenlid, Lars R.; Murphy, J. M.; Foley, Mark J.

    2013-09-01

    This work outlines the development of a multi-pinhole SPECT system designed to produce a synthetic-collimator image of a small field of view. The focused multi-pinhole collimator was constructed using rapid-prototyping and casting techniques. The collimator projects the field of view through forty-six pinholes when the detector is adjacent to the collimator. The detector is then moved further from the collimator to increase the magnification of the system. The amount of pinhole-projection overlap increases with the system magnification. There is no rotation in the system; a single tomographic angle is used in each system configuration. The maximum-likelihood expectation-maximization (MLEM) algorithm is implemented on graphics processing units to reconstruct the object in the field of view. Iterative reconstruction algorithms, such as MLEM, require an accurate model of the system response. For each system magnification, a sparsely-sampled system response is measured by translating a point source through a grid encompassing the field of view. The pinhole projections are individually identified and associated with their respective apertures. A 2D elliptical Gaussian model is applied to the pinhole projections on the detector. These coefficients are associated with the object-space location of the point source, and a finely-sampled system matrix is interpolated. Simulations with a hot-rod phantom demonstrate the efficacy of combining low-resolution non-multiplexed data with high-resolution multiplexed data to produce high-resolution reconstructions.

  8. Clinical Role of Subtraction Ictal SPECT Coregistered to MR Imaging and (18)F-FDG PET in Pediatric Epilepsy.

    PubMed

    Perissinotti, Andrés; Setoain, Xavier; Aparicio, Javier; Rubí, Sebastiá; Fuster, Berta Marti; Donaire, Antonio; Carreño, Mar; Bargalló, Nuria; Rumiá, Jordi; Garcia-Fructuoso, Gemma; Mayoral, Maria; Sanmartí, Francesc; Pons, Francesca

    2014-07-01

    A precise assessment of the drug-resistant epileptic pediatric population for surgical candidacy is often challenging, and to date there are no evidence-based guidelines for presurgical identification of the epileptogenic zone. To evaluate the usefulness of radionuclide imaging techniques for presurgical evaluation of epileptic pediatric patients, we compared the results of video-electroencephalography (EEG), brain MR imaging, interictal SPECT, ictal SPECT, subtraction ictal SPECT coregistered to MR imaging (SISCOM), and interictal PET with (18)F-FDG. Fifty-four children with drug-resistant epilepsy who had undergone video-EEG monitoring, brain MR imaging, interictal and ictal brain perfusion SPECT, SISCOM, and (18)F-FDG PET were included in this study. All abnormal findings revealed by these neuroimaging techniques were compared with the presumed location of the epileptogenic zone (PEZ) as determined by video-EEG and clinical data. The proportion of localizing studies for each technique was statistically compared. In the 18 patients who underwent resective brain surgery, neuroimaging results were compared with histopathology results and surgical outcome. SISCOM and (18)F-FDG PET concordance with the PEZ was significantly higher than MR imaging (P < 0.05). MR imaging showed localizing results in 21 of 54 cases (39%), SISCOM in 36 of 54 cases (67%), and (18)F-FDG PET in 31 of 54 cases (57%). If we consider SISCOM and (18)F-FDG PET results together, nuclear medicine imaging techniques showed coinciding video-EEG results in 76% of patients (41/54). In those cases in which MR imaging failed to identify any epileptogenic lesion (61% [33/54]), SISCOM or (18)F-FDG PET findings matched PEZ in 67% (22/33) of cases. SISCOM and (18)F-FDG PET provide complementary presurgical information that matched video-EEG results and clinical data in three fourths of our sample. SISCOM was particularly useful in those cases in which MR imaging findings were abnormal but no epileptogenic

  9. SPECT imaging of dopamine transporters with (99m)Tc-TRODAT-1 in major depression and Parkinson's disease.

    PubMed

    Wu, Hao; Lou, Cen; Huang, Zhongke; Shi, Guohua

    2011-01-01

    To investigate dopamine transporter in major depressive disorder and Parkinson's disease, the authors obtained single photon emission computed tomography (SPECT) brain images from 13 patients with major depression, 17 Parkinson's disease patients, and 10 healthy volunteers by using 99mTc-TRODAT-1. The authors found the 99mTc-TRODAT-1 radio signal in the striatum was reduced in the majority of patients with major depressive disorder, and this decrease was even more severe in patients with Parkinson's disease. The results support the hypothesis of dopamine hypofunction in major depressive disorder and suggest that deficient dopamine transporter may be involved in the etiology of severe major depressive disorder.

  10. Right prefrontal rTMS treatment for refractory auditory command hallucinations - a neuroSPECT assisted case study.

    PubMed

    Schreiber, Shaul; Dannon, Pinhas N; Goshen, Elinor; Amiaz, Revital; Zwas, Tzila S; Grunhaus, Leon

    2002-11-30

    Auditory command hallucinations probably arise from the patient's failure to monitor his/her own 'inner speech', which is connected to activation of speech perception areas of the left cerebral cortex and to various degrees of dysfunction of cortical circuits involved in schizophrenia as supported by functional brain imaging. We hypothesized that rapid transcranial magnetic stimulation (rTMS), by increasing cortical activation of the right prefrontal brain region, would bring about a reduction of the hallucinations. We report our first schizophrenic patient affected with refractory command hallucinations treated with 10 Hz rTMS. Treatment was performed over the right dorsolateral prefrontal cortex, with 1200 magnetic stimulations administered daily for 20 days at 90% motor threshold. Regional cerebral blood flow changes were monitored with neuroSPECT. Clinical evaluation and scores on the Positive and Negative Symptoms Scale and the Brief Psychiatric Rating Scale demonstrated a global improvement in the patient's condition, with no change in the intensity and frequency of the hallucinations. NeuroSPECT performed at intervals during and after treatment indicated a general improvement in cerebral perfusion. We conclude that right prefrontal rTMS may induce a general clinical improvement of schizophrenic brain function, without directly influencing the mechanism involved in auditory command hallucinations.

  11. CT, MR and SPECT imaging in temporal lobe epilepsy.

    PubMed

    Duncan, R; Patterson, J; Hadley, D M; Macpherson, P; Brodie, M J; Bone, I; McGeorge, A P; Wyper, D J

    1990-01-01

    Cranial computed tomography (CT) with modified temporal lobe technique, 0.15T magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT) were carried out on 30 patients with intractable temporal lobe epilepsy. Lateralising abnormalities were detected in 21/30 patients overall. Specific lesions were detected by CT in one patient and by MRI in seven patients (in one case bilateral). In addition CT detected asymmetry of the sylvian fissures or temporal horns in 10 patients, and MRI in eight patients. SPECT detected lateralising abnormalities in 19 patients (in five cases bilateral). It is concluded that low field MRI is superior to modified CT in demonstrating subtle structural lesions of the temporal lobe. Functional scanning with SPECT supports the evidence of origin of an epileptic focus in a substantial proportion of cases and may improve the selection of patients for surgery.

  12. MULTIMODALITY IMAGING: BEYOND PET/CT AND SPECT/CT

    PubMed Central

    Cherry, Simon R.

    2009-01-01

    Multimodality imaging with PET/CT and SPECT/CT has become commonplace in clinical practice and in preclinical and basic medical research. Do other combinations of imaging modalities have a similar potential to impact medical science and clinical medicine? The combination of PET or SPECT with MRI is an area of active research at the present time, while other, perhaps less obvious combinations, including CT/MR and PET/optical also are being studied. In addition to the integration of the instrumentation, there are parallel developments in synthesizing imaging agents that can be viewed by multiple imaging modalities. Is the fusion of PET and SPECT with CT the ultimate answer in multimodality imaging, or is it just the first example of a more general trend towards harnessing the complementary nature of the different modalities on integrated imaging platforms? PMID:19646559

  13. No evidence of perfusion abnormalities in the basal ganglia of a patient with generalized chorea-ballism and polycythaemia vera: analysis using subtraction SPECT co-registered to MRI.

    PubMed

    Kim, Woojun; Kim, Joong-Seok; Lee, Kwang-Soo; Kim, Yeong-In; Park, Chong-Won; Chung, Yong-An

    2008-10-01

    Polycythaemia vera is a well-known cause of symptomatic chorea, however, the pathophysiology of this correlation remains unclear. We report on a patient with generalized chorea-ballism associated with polycythaemia vera, and we present the findings of 99mTc-hexamethylpropylene amine oxime (HMPAO) SPECT done in both the choreic state and the non-choreic state. The SPECT during both the choreic and the non-choreic states did not reveal any definite perfusion changes in specific regions of the brain, as compared with 6 age-matched controls. In addition, the subtraction SPECT co-registered to MRI (SISCOM) analysis did not show any difference in cerebral blood flow during the choreic and non-choreic states. This result suggests that the basic mechanism of chorea associated with polycythaemia vera does not appear to be associated with a reduction in cerebral perfusion to a specific cerebral area, such as the basal ganglia or its thalamocortical connections.

  14. Determination of left ventricular mass through SPECT imaging

    SciTech Connect

    Zarate-Morales, A.; Rodriguez-Villafuerte, M.; Martinez-Rodriguez, F.; Arevila-Ceballos, N.

    1998-08-28

    An edge detection algorithm has been applied to estimate left ventricular (LV) mass from single photon emission computed tomography (SPECT) thallium-201 images. The algorithm was validated using SPECT images of a phantom. The algorithm was applied to 20 patient studies from the Hospital de Cardiologia, Centro Medico Nacional Siglo XXI. Left ventricular masses derived from the stress and redistribution studies were highly correlated (r=0.96). The average LV masses obtained were 162{+-}37 g and 169{+-}34 g in the redistribution and stress studies, respectively.

  15. Determination of left ventricular mass through SPECT imaging

    NASA Astrophysics Data System (ADS)

    Zárate-Morales, A.; Rodríguez-Villafuerte, M.; Martínez-Rodríguez, F.; Arévila-Ceballos, N.

    1998-08-01

    An edge detection algorithm has been applied to estimate left ventricular (LV) mass from single photon emission computed tomography (SPECT) thallium-201 images. The algorithm was validated using SPECT images of a phantom. The algorithm was applied to 20 patient studies from the Hospital de Cardiologia, Centro Médico Nacional Siglo XXI. Left ventricular masses derived from the stress and redistribution studies were highly correlated (r=0.96). The average LV masses obtained were 162±37 g and 169±34 g in the redistribution and stress studies, respectively.

  16. Hemimegalencephaly: A rare cause of hemihypoperfusion on 99m technetium-ethyl cysteinate dimer brain perfusion single-photon emission computed tomography.

    PubMed

    Damle, Nishikant A; Singhal, Abhinav; Mukherjee, Anirban; Sahoo, Manas Kumar; Tripathi, Madhavi; Bal, Chandrasekhar

    2013-04-01

    Hemimegalencephaly is a rare congenital neuronal migration disorder that can presents with the equally rare finding of hemihypoperfusion on brain perfusion single-photon emission computed tomography (SPECT). It is an extremely rare cause of intractable epilepsy. Technetium-99m ethyl cysteinate dimer (ECD) brain perfusion SPECT is useful in excluding other foci of hypoperfusion in the contralateral since hemispherectomy has been suggested to be the treatment of choice. Furthermore, hemimegalencephaly may present with hyper as well as hypoperfusion on ECD SPECT. We present the case of an 11-year-old male child with intractable seizures who showed hemihypoperfusion in the hemimegalecephalic hemisphere.

  17. Hemimegalencephaly: A rare cause of hemihypoperfusion on 99m technetium-ethyl cysteinate dimer brain perfusion single-photon emission computed tomography

    PubMed Central

    Damle, Nishikant A; Singhal, Abhinav; Mukherjee, Anirban; Sahoo, Manas Kumar; Tripathi, Madhavi; Bal, Chandrasekhar

    2013-01-01

    Hemimegalencephaly is a rare congenital neuronal migration disorder that can presents with the equally rare finding of hemihypoperfusion on brain perfusion single-photon emission computed tomography (SPECT). It is an extremely rare cause of intractable epilepsy. Technetium-99m ethyl cysteinate dimer (ECD) brain perfusion SPECT is useful in excluding other foci of hypoperfusion in the contralateral since hemispherectomy has been suggested to be the treatment of choice. Furthermore, hemimegalencephaly may present with hyper as well as hypoperfusion on ECD SPECT. We present the case of an 11-year-old male child with intractable seizures who showed hemihypoperfusion in the hemimegalecephalic hemisphere. PMID:24163513

  18. Improved diagnostic accuracy of lung perfusion imaging using Tc-99m MAA SPECT

    SciTech Connect

    O'Donnell, J.K.; Golish, J.A.; Go, R.T.; Risius, B.; Graor, R.A.; MacIntyre, W.J.; Feiglin, D.H.

    1984-01-01

    The addition of emission tomography (SPECT) to pulmonary perfusion imaging should improve diagnostic accuracy by detecting perfusion defects otherwise masked by superimposition of normal lung activity and by reducing problems with interpretation of defects that result from overlying soft tissue or pleural effusions. In order to examine the contribution of SPECT in the scintigraphic evaluation for pulmonary embolus (PE), the authors have obtained both planar and SPECT studies in 94 cases of suspected PE. All studies employed 3-4 mCi of Tc-99m MAA and standard six-view planar image acquisition. SPECT raw data of 64 images were then acquired over a 360 degree transaxial rotation with subsequent computer reconstruction. Xe-133 ventilation studies were performed when clinically indicated and tolerated by the patient. For 19 studies angiographic (AN) correlation was obtained within 24 hours. In 16/19 planar and SPECT both gave a high probability of PE but SPECT gave better segmental localization and showed better agreement with the number of defects seen at AN. In 3 indeterminate planar scans, 2 were low probability with SPECT and had negative AN. The third, a patient with Wegener's vasculitis, remained indeterminate with SPECT and had negative AN. Five patients with PE had repeat planar/SPECT/AN studies to evaluate response to treatment. SPECT correlated better with AN findings in each case. The authors conclude that SPECT perfusion imaging provides better anatomic accuracy for defects representing PE and is the non-invasive technique of choice for documenting response to therapy.

  19. Added value of SPECT/CT in patients suspected of having bone infection: preliminary results.

    PubMed

    Horger, Marius; Eschmann, Susanne Martina; Pfannenberg, Christina; Storek, Dieter; Vonthein, Reinhard; Claussen, Claus D; Bares, Roland

    2007-04-01

    We evaluated the contribution of SPECT/CT as an adjunct to combined three-phase bone scintigraphy (planar and SPECT) for diagnosing and localizing bone infection. Subsequently, the diagnostic performance of SPECT/CT was compared to visual fusion of SPECT with data of additional CT, X-ray, or MRI studies (SPECT + CT/X-ray/MRI). Thirty-one patients suspected of bone infection, presenting pathological findings on triple-phase bone scintigraphy, underwent additional SPECT/CT. The SPECT/CT-technology combines the acquisition of SPECT and CT data with the same imaging device enabling perfect overlay of anatomical and functional images. (99m)Tc-DPD was used as radiopharmaceutical in all patients. For data analysis findings of bone scintigraphy (planar scans as well as SPECT) were categorized as positive, negative, or equivocal for the presence of osteomyelitis. In a second step, they were compared with SPECT/CT and SPECT + CT/X-ray/MRI with respect to localization and classification of lesions. Validation was achieved by surgery, biopsy, or by clinical follow up over at least 9 months including microbiological and radiological findings. Three-phase bone scan (incl. SPECT) correctly classified 7 lesions as positive and 11 lesions as negative for osteomyelitis. Six scans were interpreted false positive, two false negative, and five as equivocal. Rating the latter as positive for osteomyelitis, sensitivity of bone scan was (78%), specificity (50%). SPECT/CT was true positive in 7 patients, and true negative in 19. There were two false positive and two false negative findings, one scan was equivocal (sensitivity 78%, specificity 86%). Definition of anatomical localization of inflammatory foci was much easier by SPECT/CT due to better depiction of underlying anatomical details. SPECT + CT/X-ray/MRI yielded the highest sensitivity (100% compared to 78% of SPECT/CT), if equivocal findings (5/31 compared to 1/31 for SPECT/CT) are rated as true positive for osteomyelitis. Among

  20. Brain single-photon emission CT physics principles.

    PubMed

    Accorsi, R

    2008-08-01

    The basic principles of scintigraphy are reviewed and extended to 3D imaging. Single-photon emission computed tomography (SPECT) is a sensitive and specific 3D technique to monitor in vivo functional processes in both clinical and preclinical studies. SPECT/CT systems are becoming increasingly common and can provide accurately registered anatomic information as well. In general, SPECT is affected by low photon-collection efficiency, but in brain imaging, not all of the large FOV of clinical gamma cameras is needed: The use of fan- and cone-beam collimation trades off the unused FOV for increased sensitivity and resolution. The design of dedicated cameras aims at increased angular coverage and resolution by minimizing the distance from the patient. The corrections needed for quantitative imaging are challenging but can take advantage of the relative spatial uniformity of attenuation and scatter. Preclinical systems can provide submillimeter resolution in small animal brain imaging with workable sensitivity.

  1. Role of SPECT and SPECT/CT in the Surgical Treatment of Primary Hyperparathyroidism

    PubMed Central

    Taubman, Michele L.; Goldfarb, Melanie; Lew, John I.

    2011-01-01

    Primary hyperparathyroidism is the most common cause of hypercalcemia in the outpatient population. This condition is usually the result of a single hyperfunctioning parathyroid gland. Targeted parathyroidectomy guided by intraoperative parathyroid hormone monitoring (IPM) through a small cervical incision has replaced traditional bilateral neck exploration (BNE) as the initial approach in the surgical treatment of primary hyperparathyroidism at many medical centers worldwide. Preoperative sestamibi-technetium 99m scintigraphy serves as an important prerequisite for successful targeted parathyroidectomy. Single-photon emission computed tomography (SPECT) and CT fusion, however, is a recent imaging technique that provides a three-dimensional functional image with advanced contrast resolution to greatly improve preoperative localization of parathyroid tumors. PMID:21776381

  2. Estimation of sensitivity and specificity of brain magnetic resonance imaging and single photon emission computed tomography in the diagnosis of olfactory dysfunction after head traumas.

    PubMed

    Atighechi, Saeid; Zolfaghari, Aliasghar; Baradaranfar, Mohammadhossein; Dadgarnia, Mohammadhossein

    2013-01-01

    Olfactory dysfunction has an incidence of 5-10% after head injury. Several objective and subjective tests had been proposed. Recent studies showed that brain single photon emission computed tomography (SPECT) and brain magnetic resonance imaging (MRI) have good diagnostic value in this era in which the most common sites of involvement were olfactory bulb and olfactory nerve in MRI and frontal lobe in SPECT. This study aimed to estimate the sensitivity and specificity of brain MRI and brain SPECT in the diagnosis of traumatic hyposmia and anosmia. From February 2009 to March 2011, 63 patients with head injury and smell complaint were selected for this study. Using an identification test and a threshold smell test, 28 were anosmic and 27 had hyposmia and the remaining 8 were normosmic. All of them underwent brain MRI and SPECT. The sensitivity of SPECT was 81.5 and 85.7% in hyposmia and anosmia, respectively. Its specificity was 87.5% in anosmia and 87.7% in anosmia. MRI sensitivity was 66.7% in hyposmia but 82.1% in anosmia. Its specificity was 85.7% in anosmia and 87.7% in anosmia. If MRI and SPECT were considered together, the sensitivity was 92.3% in hyposmia and 92% in anosmia, but the specificity was 87% in both cases. According to our study, both brain MRI and SPECT have high sensitivity and specificity in the diagnosis of traumatic anosmia, although brain SPECT is slightly superior to MRI. If the two techniques are applied together, the accuracy will be increased.

  3. Thallium-201 accumulation in cerebral candidiasis: Unexpected finding on SPECT

    SciTech Connect

    Tonami, N.; Matsuda, H.; Ooba, H.; Yokoyama, K.; Hisada, K.; Ikeda, K.; Yamashita, J. )

    1990-06-01

    The authors present an unexpected finding of Tl-201 uptake in the intracerebral lesions due to candidiasis. SPECT demonstrated the extent of the lesions and a high target-to-background ratio. The regions where abnormal Tl-201 accumulation was seen were nearly consistent with CT scans of those enhanced by a contrast agent. After treatment, most of the abnormal Tl-201 accumulation disappeared.

  4. Hemimegalencephaly: Clinical, EEG, neuroimaging, and IMP-SPECT correlation

    SciTech Connect

    Konkol, R.J.; Maister, B.H.; Wells, R.G.; Sty, J.R. )

    1990-11-01

    Iofetamine-single photon emission computed tomography (IMP-SPECT) was performed on 2 girls (5 1/2 and 6 years of age) with histories of intractable seizures, developmental delay, and unilateral hemiparesis secondary to hemimegalencephaly. Electroencephalography (EEG) revealed frequent focal discharges in 1 patient, while a nearly continuous burst suppression pattern over the malformed hemisphere was recorded in the other. IMP-SPECT demonstrated a good correlation with neuroimaging studies. In spite of the different EEG patterns, which had been proposed to predict contrasting clinical outcomes, both IMP-SPECT scans disclosed a similar decrease in tracer uptake in the malformed hemisphere. These results are consistent with the pattern of decreased tracer uptake found in other interictal studies of focal seizures without cerebral malformations. In view of recent recommendations for hemispherectomy in these patients, we suggest that the IMP-SPECT scan be used to compliment EEG as a method to define the extent of abnormality which may be more relevant to long-term prognosis than EEG alone.

  5. A COMPUTER MODEL OF LUNG MORPHOLOGY TO ANALYZE SPECT IMAGES

    EPA Science Inventory

    Measurement of the three-dimensional (3-D) spatial distribution of aerosol deposition can be performed using Single Photon Emission Computed Tomography (SPECT). The advantage of using 3-D techniques over planar gamma imaging is that deposition patterns can be related to real lun...

  6. Geometric Characterization of Multi-Axis Multi-Pinhole SPECT

    PubMed Central

    DiFilippo, Frank P.

    2008-01-01

    A geometric model and calibration process are developed for SPECT imaging with multiple pinholes and multiple mechanical axes. Unlike the typical situation where pinhole collimators are mounted directly to rotating gamma ray detectors, this geometric model allows for independent rotation of the detectors and pinholes, for the case where the pinhole collimator is physically detached from the detectors. This geometric model is applied to a prototype small animal SPECT device with a total of 22 pinholes and which uses dual clinical SPECT detectors. All free parameters in the model are estimated from a calibration scan of point sources and without the need for a precision point source phantom. For a full calibration of this device, a scan of four point sources with 360° rotation is suitable for estimating all 95 free parameters of the geometric model. After a full calibration, a rapid calibration scan of two point sources with 180° rotation is suitable for estimating the subset of 22 parameters associated with repositioning the collimation device relative to the detectors. The high accuracy of the calibration process is validated experimentally. Residual differences between predicted and measured coordinates are normally distributed with 0.8 mm full width at half maximum and are estimated to contribute 0.12 mm root mean square to the reconstructed spatial resolution. Since this error is small compared to other contributions arising from the pinhole diameter and the detector, the accuracy of the calibration is sufficient for high resolution small animal SPECT imaging. PMID:18293574

  7. Nonlinear dual reconstruction of SPECT activity and attenuation images.

    PubMed

    Liu, Huafeng; Guo, Min; Hu, Zhenghui; Shi, Pengcheng; Hu, Hongjie

    2014-01-01

    In single photon emission computed tomography (SPECT), accurate attenuation maps are needed to perform essential attenuation compensation for high quality radioactivity estimation. Formulating the SPECT activity and attenuation reconstruction tasks as coupled signal estimation and system parameter identification problems, where the activity distribution and the attenuation parameter are treated as random variables with known prior statistics, we present a nonlinear dual reconstruction scheme based on the unscented Kalman filtering (UKF) principles. In this effort, the dynamic changes of the organ radioactivity distribution are described through state space evolution equations, while the photon-counting SPECT projection data are measured through the observation equations. Activity distribution is then estimated with sub-optimal fixed attenuation parameters, followed by attenuation map reconstruction given these activity estimates. Such coupled estimation processes are iteratively repeated as necessary until convergence. The results obtained from Monte Carlo simulated data, physical phantom, and real SPECT scans demonstrate the improved performance of the proposed method both from visual inspection of the images and a quantitative evaluation, compared to the widely used EM-ML algorithms. The dual estimation framework has the potential to be useful for estimating the attenuation map from emission data only and thus benefit the radioactivity reconstruction.

  8. The aSPECT experiment - an overview and latest results

    NASA Astrophysics Data System (ADS)

    Schmidt, Christian; Aspect Collaboration

    2016-09-01

    The aSPECT retardation spectrometer measures the β- ν angular correlation coefficient a in free neutron β-decay. This measurement can be used to determine the ratio gA/gV of the weak coupling constants, as well as to search for physics beyond the Standard Model. In 2013 aSPECT had a successful beam time at the Institut Laue-Langevin. The goal of this beam time is to improve the current uncertainty of a from Δa / a 5 % to about 1%. The data analysis is in its final stage and nearly finished. In order to achieve an uncertainty of 1%, the systematics of aSPECT have to be understood accordingly. This is achieved by systematic tests and measurements of a with different parameter settings for the spectrometer during the beam time. Additionally, offline measurements have been performed to determine the effect on the systematics, e.g. work-function fluctuations of the electrodes. These measurements are used as input for on-going simulations of the spectrometer to understand and reduce the systematic uncertainties further. In this talk aSPECT will be introduced and the current status of the data analysis will be reported, including a preliminary error budget of the systematic uncertainties.

  9. A COMPUTER MODEL OF LUNG MORPHOLOGY TO ANALYZE SPECT IMAGES

    EPA Science Inventory

    Measurement of the three-dimensional (3-D) spatial distribution of aerosol deposition can be performed using Single Photon Emission Computed Tomography (SPECT). The advantage of using 3-D techniques over planar gamma imaging is that deposition patterns can be related to real lun...

  10. Small hepatocellular carcinomas in chronic liver disease: Detection with SPECT

    SciTech Connect

    Kudo, M.; Hirasa, M.; Takakuwa, H.; Ibuki, Y.; Fujimi, K.; Miyamura, M.; Tomita, S.; Komori, H.; Todo, A.; Kitaura, Y.

    1986-06-01

    Single-photon emission computed tomography (SPECT) performed using a rotating gamma camera was compared with ..cap alpha../sub 1/-fetoprotein (AFP) assay, conventional liver scintigraphy, ultrasound (US) imaging, computed tomography (CT), and selective celiac angiography in 40 patients with a total of 50 small hepatocellular carcinomas (HCCs;<5 cm). The detection rates of US and CT were determined on an initial screening study and on a second, more precisely focused study. The detection rate of small HCCs by the various modalities was as follows: AFP, 13%; liver scintigraphy, 36%; SPECT, 72%; initial screening US, 80%; second, more precise US studies, 94%; initial screening CT, 64%; second, more precise CT study, 82%; angiography, 88%. Although SPECT was inferior to the initial screening US examination in detecting HCCs less than 2 cm in size, its sensitivity was identical to that of the initial screening US study for detecting HCCs of 2-5 cm. The combination of SPECT and US was an excellent method for the early detection of HCCs, yielding a detection rate of 94%.

  11. Evaluation of SPECT quantification of radiopharmaceutical distribution in canine myocardium

    SciTech Connect

    Li, Jianying; Jaszczak, R.L.; Greer, K.L.

    1995-02-01

    This study evaluates the quantitative accuracy of SPECT for in vivo distributions of {sup 99m}Tc radiopharmaceuticals using fanbeam (FB) and parallel-beam (PB) collimators and compares uniform and nouniform attenuation correction methods in terms of quantitative accuracy. SPECT quantification of canine myocardial radioactivity was performed followed by well counter measurements of extracted myocardial tissue samples. Transmission scans using a line source and an FB collimator were performed to generate nonuniform attenuation maps of the canine thorax. Emission scans with two energy windows were acquired. Images were reconstructed using a filtered backprojection algorithm, with a dual-window scatter subtraction combined with either no attenuation compensation or single iteration Chang attenuation compensation based on a uniform attenuation map {mu}=0.152 cm{sup -1} or the nonuniform transmission map. The measured mean counts from the SPECT images were converted using the well counter. The experimental results demonstrate that, compared with well counter values, the in vivo distributions of {sup 99m}Tc were most accurately determined in FB and PB SPECT reconstructions with nonuniform attenuation compensation, under-estimated without attenuation compensation and overestimated with uniform attenuation compensation. 37 refs., 9 figs., 10 tabs.

  12. Thallium-201 SPECT increases detectability of thyroid cancer metastases

    SciTech Connect

    Charkes, N.D.; Vitti, R.A.; Brooks, K. )

    1990-02-01

    Thallium-201- ({sup 201}Tl) chloride is known to accumulate in metastatic foci of differentiated thyroid carcinoma, but small and deep-seated lesions are generally not detectable by planar imaging. We have evaluated the use of 201Tl-chloride single-photon emission computed tomography (SPECT) in 41 post-thyroidectomy patients with differentiated thyroid carcinoma and one with medullary carcinoma; planar imaging alone was done in eight additional patients (total 50). Of 20 patients with known metastatic disease, planar {sup 201}Tl images were positive in 12 (60%) but SPECT revealed an additional 5 (25%) who had metastases (total 85%). SPECT revealed foci as small as 1.0 cm in the neck and 1.5 cm in the lungs, and was particularly useful in detection of disseminated micronodular pulmonary metastases, especially in patients whose scans were negative with diagnostic doses of {sup 131}I. Some pitfalls in interpretation of the tomographic reconstructions were found. Thallium-201 SPECT is a marked improvement over planar imaging in the detection of metastases of differentiated thyroid cancer.

  13. CALOR87: HETC87, MICAP, EGS4, and SPECT

    SciTech Connect

    Gabriel, T.A.; Alsmiller, F.S.; Alsmiller, R.G. Jr.; Bishop, B.L.; Hermann, O.W.; Johnson, J.O.

    1987-01-01

    A brief history of CALOR (HETC, EGS, MICAP, SPECT) is presented to indicate the evolution of this code system. Details concerning the current modifications and additions to the high-energy transport code, HETC, are also presented and new comparisons with experimental data are included to verify the new physics improvements. 27 refs., 5 figs.

  14. Nonlinear Dual Reconstruction of SPECT Activity and Attenuation Images

    PubMed Central

    Liu, Huafeng; Guo, Min; Hu, Zhenghui; Shi, Pengcheng; Hu, Hongjie

    2014-01-01

    In single photon emission computed tomography (SPECT), accurate attenuation maps are needed to perform essential attenuation compensation for high quality radioactivity estimation. Formulating the SPECT activity and attenuation reconstruction tasks as coupled signal estimation and system parameter identification problems, where the activity distribution and the attenuation parameter are treated as random variables with known prior statistics, we present a nonlinear dual reconstruction scheme based on the unscented Kalman filtering (UKF) principles. In this effort, the dynamic changes of the organ radioactivity distribution are described through state space evolution equations, while the photon-counting SPECT projection data are measured through the observation equations. Activity distribution is then estimated with sub-optimal fixed attenuation parameters, followed by attenuation map reconstruction given these activity estimates. Such coupled estimation processes are iteratively repeated as necessary until convergence. The results obtained from Monte Carlo simulated data, physical phantom, and real SPECT scans demonstrate the improved performance of the proposed method both from visual inspection of the images and a quantitative evaluation, compared to the widely used EM-ML algorithms. The dual estimation framework has the potential to be useful for estimating the attenuation map from emission data only and thus benefit the radioactivity reconstruction. PMID:25225796

  15. Geometric characterization of multi-axis multi-pinhole SPECT

    SciTech Connect

    DiFilippo, Frank P.

    2008-01-15

    A geometric model and calibration process are developed for single photon emission computed tomography (SPECT) imaging with multiple pinholes and multiple mechanical axes. Unlike the typical situation where pinhole collimators are mounted directly to rotating gamma ray detectors, this geometric model allows for independent rotation of the detectors and pinholes, for the case where the pinhole collimator is physically detached from the detectors. This geometric model is applied to a prototype small animal SPECT device with a total of 22 pinholes and which uses dual clinical SPECT detectors. All free parameters in the model are estimated from a calibration scan of point sources and without the need for a precision point source phantom. For a full calibration of this device, a scan of four point sources with 360 deg. rotation is suitable for estimating all 95 free parameters of the geometric model. After a full calibration, a rapid calibration scan of two point sources with 180 deg. rotation is suitable for estimating the subset of 22 parameters associated with repositioning the collimation device relative to the detectors. The high accuracy of the calibration process is validated experimentally. Residual differences between predicted and measured coordinates are normally distributed with 0.8 mm full width at half maximum and are estimated to contribute 0.12 mm root mean square to the reconstructed spatial resolution. Since this error is small compared to other contributions arising from the pinhole diameter and the detector, the accuracy of the calibration is sufficient for high resolution small animal SPECT imaging.

  16. Cerebral-perfusion-based single-photon emission computed tomography (SPECT) staging using NeuroGam® in patients with moyamoya disease.

    PubMed

    Han, Jai-Hyuck; Park, Young Seok; Lee, Won Hyoung; Koong, Sung-Soo; Min, Kyung-Soo; Lee, Mou-Seop; Kim, Young-Gyu; Kim, Dong-Ho; Yi, Kyung-Sil; Cha, Sang-Hoon

    2016-08-01

    Cerebral angiography (CA) is the gold standard for moyamoya disease (MMD) staging and diagnosis, but CA findings are not well correlated with clinical symptoms. The purpose of this study was to establish novel cerebral-perfusion-based staging for MMD that is well correlated with clinical symptoms. From 2010 to 2015, regional cerebrovascular reserve (rCVR) was examined by single-photon emission computed tomography (SPECT) using NeuroGam® (Segamicorp, Houston, TX, USA) in 30 patients (17 women, 13 men; 60 hemispheres; mean 42.0 years old [range 5-60 years old]) with MMD, which was diagnosed by CA and magnetic resonance angiography (MRA). Brain CT or brain magnetic resonance imaging (MRI) was used to evaluate neurological conditions such as transient ischemic attack (TIA), cerebral hemorrhage, and cerebral infarction. A novel staging system for MMD was developed by combining findings from CA, MRI, and SPECT with NeuroGam®. Our novel staging system was strongly associated with clinical symptoms. Twenty-two hemispheres out of 60 were categorized as stage I, 24 hemispheres were categorized as stage II, and 14 hemispheres were categorized as stage III. Hemispheres with higher scores exhibited a higher incidence of clinical symptoms. These findings indicate that cerebral-perfusion-based staging is predictive of MMD clinical symptoms. Perfusion-based SPECT staging correlates well with clinical symptoms and may be a reliable alternative to the Suzuki staging by CA.

  17. Multi-modal brain imaging showing brain damage to the orbitofrontal cortex and left hemisphere, in a case of prolonged hypoglycemia-induced transient hemiplegia followed by persistent encephalopathy.

    PubMed

    Koike, Shinsuke; Sasaki, Ryuichi

    2013-07-01

    A 21-year-old left-handed male patient was admitted with a 19-h history of coma after substantial insulin injection for suicide attempt. Although the patient recovered from coma 3 days after injury, he experienced transient hemiplegia followed by permanent brain damage. Electroencephalogram (EEG), brain magnetic resonance imaging (MRI), and brain single-photon emission computed tomography (SPECT) identified the localization of this dysfunction, but consistency between clinical symptoms and brain images changed depending on the course of treatment. Transient hemiplegia corresponded to abnormal waveforms on EEG and decreased cerebral blood flow on SPECT, whereas persistent dysfunctions corresponded to abnormal brain regions on MRI and SPECT. © 2013 The Authors. Psychiatry and Clinical Neurosciences © 2013 Japanese Society of Psychiatry and Neurology.

  18. [Variables that influence the indication of a second myocardial perfusion gated-SPECT after a normal stress-rest gated SPECT].

    PubMed

    Romero-Farina, G; Candell-Riera, J; Aguadé-Bruix, S; Cuberas-Borrós, G; Pizzi, M N; Santos, A; de León, G; García-Dorado, D

    2014-01-01

    The objective of this study was to investigate predictor variables at the moment of normal stress-rest myocardial perfusion gated SPECT for indication of a second gated SPECT. A prospective, single center cohort study was conducted. We evaluated 2326 consecutive patients (age 63.6 ± 13 years, 57.3% females) without perfusion defects and with normal left ventricular ejection fraction on a myocardial perfusion gated SPECT. Clinical and stress test variables were studied to predict indication of a second gated SPECT and presence of reversible perfusion defects in the second gated SPECT. During a mean follow-up of 3.6 ± 2 years a second gated SPECT was performed in 286 patients (12.3%). Independent predictor variables of a second gated SPECT were presence of three or more cardiovascular risk factors (χ(2): 5.510; HR: 1.4; p=0.019), previous acute myocardial infarction (χ(2): 3.867; HR: 1.4; p=0.049), previous coronary revascularization (χ(2): 41.081; HR: 2.5; p<0.001), and a positive stress test (χ(2): 8.713; HR: 1.5; p=0.003). Observation of perfusion defects in the 280 patients in whom a second stress-rest gated SPECT was performed was more likely in male patients (χ(2): 4.322; HR: 1.9; p=0.038) who had a first pure pharmacological gated-SPECT (χ(2): 7.182; HR: 2.6; p=0.007). In patients with a first normal myocardial perfusion gated SPECT, various clinical factors and variables derived from the stress test affect the indication of a second gated SPECT and the presence of ischemia in the latter. Copyright © 2013 Elsevier España, S.L. and SEMNIM. All rights reserved.

  19. Affordable CZT SPECT with dose-time minimization (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Hugg, James W.; Harris, Brian W.; Radley, Ian

    2017-03-01

    PURPOSE Pixelated CdZnTe (CZT) detector arrays are used in molecular imaging applications that can enable precision medicine, including small-animal SPECT, cardiac SPECT, molecular breast imaging (MBI), and general purpose SPECT. The interplay of gamma camera, collimator, gantry motion, and image reconstruction determines image quality and dose-time-FOV tradeoffs. Both dose and exam time can be minimized without compromising diagnostic content. METHODS Integration of pixelated CZT detectors with advanced ASICs and readout electronics improves system performance. Because historically CZT was expensive, the first clinical applications were limited to small FOV. Radiation doses were initially high and exam times long. Advances have significantly improved efficiency of CZT-based molecular imaging systems and the cost has steadily declined. We have built a general purpose SPECT system using our 40 cm x 53 cm CZT gamma camera with 2 mm pixel pitch and characterized system performance. RESULTS Compared to NaI scintillator gamma cameras: intrinsic spatial resolution improved from 3.8 mm to 2.0 mm; energy resolution improved from 9.8% to <4 % at 140 keV; maximum count rate is <1.5 times higher; non-detection camera edges are reduced 3-fold. Scattered photons are greatly reduced in the photopeak energy window; image contrast is improved; and the optimal FOV is increased to the entire camera area. CONCLUSION Continual improvements in CZT detector arrays for molecular imaging, coupled with optimal collimator and image reconstruction, result in minimized dose and exam time. With CZT cost improving, affordable whole-body CZT general purpose SPECT is expected to enable precision medicine applications.

  20. Advanced reconstruction of attenuation maps using SPECT emission data only

    NASA Astrophysics Data System (ADS)

    Salomon, André; Goedicke, Andreas; Aach, Til

    2009-02-01

    Today, attenuation corrected SPECT, typically performed using CT or Gadolinium line source based transmission scans, is more and more becoming standard in many medical applications. Moreover, the information about the material density distribution provided by these scans is key for other artifact compensation approaches in advanced SPECT reconstruction. Major drawbacks of these approaches are the additional patient radiation and hardware/maintenance costs as well as the additional workflow effort, e.g. if the CT scans are not performed on a hybrid scanner. It has been investigated in the past, whether it is possible to recover this structural information solely from the SPECT scan data. However, the investigated methods often result in noticeable image artifacts due to cross-dependences between attenuation and activity distribution estimation. With the simultaneous reconstruction method presented in this paper, we aim to effectively prevent these typical cross-talk artifacts using a-priori known atlas information of a human body. At first, an initial 3D shape model is coarsely registered to the SPECT data using anatomical landmarks and each organ structure within the model is identified with its typical attenuation coefficient. During the iterative reconstruction based on a modified ML-EM scheme, the algorithm simultaneously adapts both, the local activity estimation and the 3D shape model in order to improve the overall consistency between measured and estimated sinogram data. By explicitly avoiding topology modifications resulting in a non-anatomical state, we ensure that the estimated attenuation map remains realistic. Several tests with simulated as well as real patient SPECT data were performed to test the proposed algorithm, which demonstrated reliable convergence behaviour in both cases. Comparing the achieved results with available reference data, an overall good agreement for both cold as well as hot activity regions could be observed (mean deviation: -5.98%).

  1. [Cost-effectiveness of stress-only myocardial perfusion single photon emission computed tomography (SPECT) imaging].

    PubMed

    Vallejo, Enrique; Acevedo, César; Varela, Samuel; Alburez, José Carlos; Bialostozky, David

    2012-01-01

    Single photon emission computed tomography (SPECT) myocardial perfusion imaging is widely used for diagnosing coronary artery disease (CAD). However, SPECT costs, imaging time, and radiation exposure, limit SPECT indications. Determine whether a stress-only SPECT imaging would be enough to obtain a diagnosis of CAD improving nuclear laboratory efficiency. 122 patients with unknown CAD were evaluated with stress-only SPECT imaging. In order to evaluate diagnostic accuracy and the prognostic value of the stress-only protocol, patients with abnormal SPECT underwent invasive angiography and patients with normal SPECT were followed-up during 3 years. Diagnosis time, SPECT cost, and radiopharmaceutical dosage were significantly lower as compared with the conventional SPECT imaging protocol (30, 40 and 55%, respectively). Diagnostic accuracy and cardiac prognosis information were comparable to those obtained with the conventional imaging protocol (positive predictive value for CAD of 85% and negative predictive value for cardiac events of 97%). In patients with intermediate risk for CAD, stress-only SPECT imaging will significantly improve nuclear laboratory efficiency, and with similar accuracy than that the one obtained with the conventional protocol.

  2. Can hybrid SPECT-CT overcome the limitations associated with poor imaging properties of 131I-MIBG?: Comparison with planar scintigraphy and SPECT in pheochromocytoma.

    PubMed

    Sharma, Punit; Dhull, Varun Singh; Jeph, Sunil; Reddy, Rama Mohan; Singh, Harmandeep; Naswa, Niraj; Bal, Chandrasekhar; Kumar, Rakesh

    2013-09-01

    This study aimed to evaluate the incremental value of (131)I-MIBG hybrid SPECT-CT over planar scintigraphy (PS) and SPECT alone in patients with clinical or biochemical suspicion of pheochromocytoma. A total of 126 adrenals of 63 patients (mean [SD] age, 28.6 [15.7] years; male patients, n = 34; female patients, n = 29) with clinical or biochemical suspicion of pheochromocytoma were retrospectively evaluated. All patients had undergone (131)I-MIBG SPECT-CT of adrenal region. The PS, SPECT, and SPECT-CT images were independently evaluated by 2 nuclear medicine physicians with 6 years (R1) and 2 years (R2) experience and in separate sessions 1 week apart. A scoring scale of 1 to 5 was used, in which 1 is definitely abnormal, 2 is probably abnormal, 3 is indeterminate, 4 is probably normal, and 5 is definitely normal. Sensitivity, specificity, predictive values were calculated taking a score 2 or less as abnormal. With receiver operating characteristic (ROC) curve analysis, areas under the curve (AUC) were calculated for each modality and compared. Histopathology and/or clinical/imaging follow-up were taken as reference standard. Of the 126 adrenals evaluated, 29 were indeterminate on PS for R1 and 48 for R2, 39 were indeterminate on SPECT for both, and on SPECT-CT, 1 was indeterminate for R1 and 2 for R2. SPECT-CT correctly characterized 28 of 29 indeterminate adrenals on PS and 37 of 39 indeterminate adrenals on SPECT for R1. Similarly, for R2, SPECT-CT correctly characterized 45 of 48 indeterminate adrenals on PS and 33 of 39 indeterminate adrenals on SPECT. On ROC comparison, PS was inferior to SPECT (P = 0.040 for R1; P < 0.001 for R2) and SPECT-CT (P = 0.001 for R1; P < 0.001 for R2) for both the observers. Moreover, SPECT was inferior to SPECT-CT for both the observers (P = 0.017 for R1 and P = 0.001 for R2). Accuracy of SPECT-CT (R1, 97.6%; R2, 97.6%) was higher than PS (R1, 91.2%; R2, 84.1%) and SPECT (R1, 94.4%; R2, 86.5%). Interobserver agreement was

  3. Comparison of planar and SPECT thallium imaging in men and women

    SciTech Connect

    Links, J.M.; Fintel, D.F.; Becker, L.C.; Wagner, H.N. Jr.

    1985-05-01

    The authors studied the overall accuracy of planar and SPECT Tl imaging in the diagnosis of coronary artery disease (CAD) in 85 subjects (65 males, 20 females; 52 with angiographic CAD, 33 without CAD), and then separately analyzed men and women to see if factors such as breast attenuation significantly alter the accuracy. All subjects were exercised to symptom-limit or peak heart rate achievement, and injected with 2 mCi Tl-201. Planar and SPECT stress studies were acquired in a random order, with delayed studies acquired 3 hours after injection. The studies were viewed in a blinded, random order, and interpreted on a 5 point scale by consensus of 3 observers (1: definitely normal, 2: probably normal, 3: equivocal, 4: probably abnormal, 5: definitely abnormal). Receiver operating characteristic (ROC) curves were constructed for overall planar and SPECT, and then separately for male planar, male SPECT, female planar, female SPECT. The overall SPECT curve was above the overall planar curve. The overall SPECT curve was above the overall planar curve. At a specificity of 90%, SPECT sensitivity was 93%, planar was 80%. For both males and females, the SPECT curves were above the planar curves. However, both planar and SPECT male curves were above both female curves. At a specificity of 90%, sensitivities were male planar, 83%; male SPECT, 97%; female planar, 50%; female SPECT, 80%. This difference in accuracy between males and females was not due to adequacy of exercise (peak exercise heart rate in CAD pts: males, 145 +- 28 bpm; females, 151 +- 28; p=NS; in normals: 178 bpm for both males and females). SPECT is more accurate than planar imaging in the diagnosis of CAD. However, differences in accuracy exist between men and women, which may be due to breast attenuation.

  4. Validation of a short-scan-time imaging protocol for thallium-201 myocardial SPECT with a multifocal collimator.

    PubMed

    Horiguchi, Yoriko; Ueda, Tomohiro; Shiomori, Tomofumi; Kanna, Masahiko; Matsushita, Hirooki; Kawaminami, Tomoko; Sudo, Yuta; Kikuchi, Shinnosuke; Sasaki, Ryo; Hoshimiya, Jun; Morita, Yukiko

    2014-10-01

    IQ-SPECT (Siemens AG, Munich, Germany) is a highly sensitive single-photon-emission computed tomography (SPECT) myocardial perfusion imaging (MPI) system that uses a multifocal collimator. We searched for a suitable protocol for short-time imaging by IQ-SPECT in thallium-201 (Tl-201) MPI by evaluating phantom images and also by comparing human IQ-SPECT images with conventional SPECT images as reference standards. We assessed the image quality using the normalized mean square error (NMSE) and drew up count profiles in Tl-201 SPECT images acquired with IQ-SPECT in a phantom study. We also performed Tl-201 stress myocardial SPECT/CT in 21 patients and compared delayed images acquired by using IQ-SPECT with 36 or 17 views per head with images obtained by using conventional SPECT. The NMSE of SPECT images from IQ-SPECT with 36 views was approximately one-fifth of that with 17 views. The myocardial count profile of images with 17 views was lower than those of images with 36 or 104 views in some regions. Defect scores were significantly lower, and image quality scores higher, in images from conventional SPECT than in those from IQ-SPECT with 17 views. Defect scores and image quality scores were equivalent in images from conventional SPECT and those from IQ-SPECT with 36 views. Agreement with the results of conventional SPECT in terms of coronary artery territory-based defect judgment was the best in IQ-SPECT with 36 views with computed tomography-derived attenuation correction (CTAC): the kappa values for IQ-SPECT with 36 views were 0.76 (without CTAC) and 0.83 (with CTAC), and those for IQ-SPECT with 17 views were 0.62 (without CTAC) and 0.59 (with CTAC). The difference in quantitative tracer uptake between conventional SPECT images and IQ-SPECT images was significantly greater for IQ-SPECT images with 17 views than for those with 36 views. Scanning with 36 views per head with CTAC may be appropriate for Tl-201 MPI using IQ-SPECT, because it provides images equivalent to

  5. Activity concentration measurements using a conjugate gradient (Siemens xSPECT) reconstruction algorithm in SPECT/CT.

    PubMed

    Armstrong, Ian S; Hoffmann, Sandra A

    2016-11-01

    The interest in quantitative single photon emission computer tomography (SPECT) shows potential in a number of clinical applications and now several vendors are providing software and hardware solutions to allow 'SUV-SPECT' to mirror metrics used in PET imaging. This brief technical report assesses the accuracy of activity concentration measurements using a new algorithm 'xSPECT' from Siemens Healthcare. SPECT/CT data were acquired from a uniform cylinder with 5, 10, 15 and 20 s/projection and NEMA image quality phantom with 25 s/projection. The NEMA phantom had hot spheres filled with an 8 : 1 activity concentration relative to the background compartment. Reconstructions were performed using parameters defined by manufacturer presets available with the algorithm. The accuracy of activity concentration measurements was assessed. A dose calibrator-camera cross-calibration factor (CCF) was derived from the uniform phantom data. In uniform phantom images, a positive bias was observed, ranging from ∼6% in the lower count images to ∼4% in the higher-count images. On the basis of the higher-count data, a CCF of 0.96 was derived. As expected, considerable negative bias was measured in the NEMA spheres using region mean values whereas positive bias was measured in the four largest NEMA spheres. Nonmonotonically increasing recovery curves for the hot spheres suggested the presence of Gibbs edge enhancement from resolution modelling. Sufficiently accurate activity concentration measurements can easily be measured on images reconstructed with the xSPECT algorithm without a CCF. However, the use of a CCF is likely to improve accuracy further. A manual conversion of voxel values into SUV should be possible, provided that the patient weight, injected activity and time between injection and imaging are all known accurately.

  6. Thallium-201 SPECT in prognostic assessment of malignant gliomas treated with postoperative radiotherapy.

    PubMed

    Semba, Takatoshi; Sugawara, Yoshifumi; Ochi, Takashi; Fujii, Takashi; Mochizuki, Teruhito; Ohnishi, Takanori

    2006-05-01

    This study was designed to investigate the value of preoperative thallium-201 (201Tl) SPECT as a predictor of outcome in malignant glioma. From January 1990 to September 2003, 109 patients with glioma were treated with postoperative radiotherapy. Of these, 36 patients with malignant gliomas who underwent preoperative 201Tl-SPECT were included in this study (grade 3: n=14, grade 4: n=22). On early (10 minutes) and delayed (2 hours) images after 111 MBq 201TlCl injection, we calculated radioactivity ratios of tumors to contralateral normal brain (T/N ratios) and retention indices (RIs). For early and delayed images, we compared outcome between a high T/N ratio group (T/N ratio equal or greater than the average) and a low T/N ratio group (T/N ratio less than the average). We also divided the patients into two groups on the basis of RI; a high RI group (RI equal or greater than the average) and a low RI group (RI less than the average), and similarly compared outcome between the two groups. Median survival time was 12 months for both grade 3 and grade 4 tumors; however, two-year survival was 53% for grade 3 and 15% for grade 4. In both early and delayed images, outcome was significantly better for patients with low T/N ratios (early < 4.71, delayed < 3.96) than those with high T/N ratios (early: p = 0.030, delayed: p = 0.049). However, no significant survival difference was apparent between the low- (< -12.25) and high RI groups. In grade 3 glioma, patients with high T/N ratios demonstrated a tendency toward poorer outcome, although this trend was not significant (early: p = 0.079, delayed: p = 0.099). Overall outcome was poor for grade 4 glioma, and the difference in survival between low and high T/N ratio groups was not significant (early: p = 0.51, delayed: p = 0.53). However, long survival was seen only in patients with lower T/N ratios. Differences of 201Tl uptake in malignant gliomas could predict outcome. 201Tl-SPECT is potentially useful in the management of

  7. A combined static-dynamic single-dose imaging protocol to compare quantitative dynamic SPECT with static conventional SPECT.

    PubMed

    Sciammarella, Maria; Shrestha, Uttam M; Seo, Youngho; Gullberg, Grant T; Botvinick, Elias H

    2017-08-03

    SPECT myocardial perfusion imaging (MPI) is a clinical mainstay that is typically performed with static imaging protocols and visually or semi-quantitatively assessed for perfusion defects based upon the relative intensity of myocardial regions. Dynamic cardiac SPECT presents a new imaging technique based on time-varying information of radiotracer distribution, which permits the evaluation of regional myocardial blood flow (MBF) and coronary flow reserve (CFR). In this work, a preliminary feasibility study was conducted in a small patient sample designed to implement a unique combined static-dynamic single-dose one-day visit imaging protocol to compare quantitative dynamic SPECT with static conventional SPECT for improving the diagnosis of coronary artery disease (CAD). Fifteen patients (11 males, four females, mean age 71 ± 9 years) were enrolled for a combined dynamic and static SPECT (Infinia Hawkeye 4, GE Healthcare) imaging protocol with a single dose of (99m)Tc-tetrofosmin administered at rest and a single dose administered at stress in a one-day visit. Out of 15 patients, eleven had selective coronary angiography (SCA), 8 within 6 months and the rest within 24 months of SPECT imaging, without intervening symptoms or interventions. The extent and severity of perfusion defects in each myocardial region was graded visually. Dynamically acquired data were also used to estimate the MBF and CFR. Both visually graded images and estimated CFR were tested against SCA as a reference to evaluate the validity of the methods. Overall, conventional static SPECT was normal in ten patients and abnormal in five patients, dynamic SPECT was normal in 12 patients and abnormal in three patients, and CFR from dynamic SPECT was normal in nine patients and abnormal in six patients. Among those 11 patients with SCA, conventional SPECT was normal in 5, 3 with documented CAD on SCA with an overall accuracy of 64%, sensitivity of 40% and specificity of 83%. Dynamic SPECT image

  8. Simultaneous 99mtc/111in spect reconstruction using accelerated convolution-based forced detection monte carlo

    NASA Astrophysics Data System (ADS)

    Karamat, Muhammad I.; Farncombe, Troy H.

    2015-10-01

    Simultaneous multi-isotope Single Photon Emission Computed Tomography (SPECT) imaging has a number of applications in cardiac, brain, and cancer imaging. The major concern however, is the significant crosstalk contamination due to photon scatter between the different isotopes. The current study focuses on a method of crosstalk compensation between two isotopes in simultaneous dual isotope SPECT acquisition applied to cancer imaging using 99mTc and 111In. We have developed an iterative image reconstruction technique that simulates the photon down-scatter from one isotope into the acquisition window of a second isotope. Our approach uses an accelerated Monte Carlo (MC) technique for the forward projection step in an iterative reconstruction algorithm. The MC estimated scatter contamination of a radionuclide contained in a given projection view is then used to compensate for the photon contamination in the acquisition window of other nuclide. We use a modified ordered subset-expectation maximization (OS-EM) algorithm named simultaneous ordered subset-expectation maximization (Sim-OSEM), to perform this step. We have undertaken a number of simulation tests and phantom studies to verify this approach. The proposed reconstruction technique was also evaluated by reconstruction of experimentally acquired phantom data. Reconstruction using Sim-OSEM showed very promising results in terms of contrast recovery and uniformity of object background compared to alternative reconstruction methods implementing alternative scatter correction schemes (i.e., triple energy window or separately acquired projection data). In this study the evaluation is based on the quality of reconstructed images and activity estimated using Sim-OSEM. In order to quantitate the possible improvement in spatial resolution and signal to noise ratio (SNR) observed in this study, further simulation and experimental studies are required.

  9. Improved SPECT quantitation using fully three-dimensional iterative spatially variant scatter response compensation.

    PubMed

    Beekman, F J; Kamphuis, C; Viergever, M A

    1996-01-01

    The quality and quantitative accuracy of iteratively reconstructed SPECT images improves when better point spread function (PSF) models of the gamma camera are used during reconstruction. Here, inclusion in the PSF model of photon crosstalk between different slices caused by limited gamma camera resolution and scatter is examined. A three-dimensional (3-D) projector back-projector (proback) has been developed which models both the distance dependent detector point spread function and the object shape-dependent scatter point spread function of single photon emission computed tomography (SPECT). A table occupying only a few megabytes of memory is sufficient to represent this scatter model. The contents of this table are obtained by evaluating an analytical expression for object shape-dependent scatter. The proposed approach avoids the huge memory requirements of storing the full transition matrix needed for 3-D reconstruction including object shape-dependent scatter. In addition, the method avoids the need for lengthy Monte Carlo simulations to generate such a matrix. In order to assess the quantitative accuracy of the method, reconstructions of a water filled cylinder containing regions of different activity levels and of simulated 3-D brain projection data have been evaluated for technetium-99m. It is shown that fully 3-D reconstruction including complete detector response and object shape-dependent scatter modeling clearly outperforms simpler methods that lack a complete detector response and/or a complete scatter response model. Fully 3-D scatter correction yields the best quantitation of volumes of interest and the best contrast-to-noise curves.

  10. The relation between persistent coma and brain ischemia after severe brain injury.

    PubMed

    Cheng, Quan; Jiang, Bing; Xi, Jian; Li, Zhen Yan; Liu, Jin Fang; Wang, Jun Yu

    2013-12-01

    To investigate the relation between brain ischemia and persistent vegetative state after severe traumatic brain injury. The 66 patients with severe brain injury were divided into two groups: The persistent coma group (coma duration ≥10 d) included 51 patients who had an admission Glasgow Coma Scale (GCS) of 5-8 and were unconscious for more than 10 d. There were 15 patients in the control group, their admission GCS was 5-8, and were unconscious for less than 10 d. The brain areas, including frontal, parietal, temporal, occipital lobes and thalamus, were measured by Single Photon Emission Computed Tomography (SPECT). In the first SPECT scan, multiple areas of cerebral ischemia were documented in all patients in both groups, whereas bilateral thalamic ischemia were presented in all patients in the persistent coma group and were absented in the control group. In the second SPECT scan taken during the period of analepsia, with an indication that unilateral thalamic ischemia were persisted in 28 of 41 patients in persistent coma group(28/41,68.29%). Persistent coma after severe brain injury is associated with bilateral thalamic ischemia.

  11. Three-minute SPECT/CT is sufficient for the assessment of bone metastasis as add-on to planar bone scintigraphy: prospective head-to-head comparison to 11-min SPECT/CT.

    PubMed

    Zacho, Helle D; Manresa, José A Biurrun; Aleksyniene, Ramune; Ejlersen, June A; Fledelius, Joan; Bertelsen, Henrik; Petersen, Lars J

    2017-12-01

    The aim of this study is to assess whether ultra-fast acquisition SPECT/CT (UF-SPECT/CT) can replace standard SPECT/CT (std-SPECT/CT) as "add-on" to whole-body bone scintigraphy (WB-BS) for the investigation of bone metastases. Consecutive cancer patients referred for WB-BS who underwent SPECT/CT in addition to WB-BS were included. Std-SPECT, UF-SPECT, and low-dose CT were performed (std-SPECT: matrix 128 × 128, zoom factor 1, 20 s/view, 32 views; UF-SPECT: identical parameters except for 10 s/view and 16 views, reducing the acquisition time from 11 to 3 min). A consensus diagnosis was reached by two observers for each set of images (WB-BS + standard SPECT/CT or WB-BS + UF-SPECT/CT) using a three-category evaluation scale: M0: no bone metastases; M1: bone metastases; and Me: equivocal findings. Among the 104 included patients, most presented with prostate cancer (n = 71) or breast cancer (n = 28). Using WB-BS + std-SPECT/CT, 71 (68%) patients were classified as M0, 19 (18%) as M1, and 14 (14%) as Me. Excellent agreement was observed between WB-BS + std-SPECT/CT and WB-BS + UF-SPECT/CT using the three-category scale: kappa = 0.91 (95% CI 0.84-0.97). No difference in observer agreement between cancer types was detected. SPECT/CT provided a definitive classification in 90 of 104 cases in which WB-BS was not entirely diagnostic. To investigate potential bone metastases, UF-SPECT/CT can be conducted as add-on to WB-BS to notably reduce the SPECT acquisition time without compromising diagnostic confidence.

  12. 3D-OSEM and FP-CIT SPECT quantification: benefit for studies with a high radius of rotation?

    PubMed

    Koch, Walter; Bartenstein, Peter; la Fougère, Christian

    2013-10-01

    Dopamine transporter imaging with single-photon emission computed tomography (SPECT) is a valuable tool for both clinical routine and research studies. Recently, it was found that the image quality could be improved by introduction of the three-dimensional ordered subset expectation maximization (3D-OSEM) reconstruction algorithm, which provides resolution recovery. The aim of this study was to systematically evaluate the potential benefits of 3D-OSEM in comparison with 2D-OSEM under critical imaging conditions, for example, scans with a high radius of rotation. Monte Carlo simulation scans of a digital brain phantom with various disease states and different radii of rotation ranging from 13 to 30 cm were reconstructed with both 2D-OSEM and 3D-OSEM algorithms. Specific striatal binding and putamen-to-caudate ratios were determined and compared with true values in the phantom. The percentage recovery of true striatal binding was similar between both reconstruction algorithms at the minimum rotational radius; however, at the maximum rotational radius, it decreased from 53 to 43% for 3D-OSEM and from 52 to 26% for 2D-OSEM. 3D-OSEM matched the true putamen-to-caudate ratios more closely than did 2D-OSEM in scans with high SPECT rotation radii. 3D-OSEM offers a promising image quality gain. It outperforms 2D-OSEM, particularly in studies with limited resolutions (such as scans acquired with a high radius of rotation) but does not improve the accuracy of the putamen-to-caudate ratios. Whether the benefits of better recovery in studies with higher radii of rotation could potentially increase the diagnostic power of dopamine transporter SPECT in patients with borderline striatal radiotracer binding, however, needs to be further examined.

  13. EANM procedural guidelines for radionuclide myocardial perfusion imaging with SPECT and SPECT/CT: 2015 revision.

    PubMed

    Verberne, Hein J; Acampa, Wanda; Anagnostopoulos, Constantinos; Ballinger, Jim; Bengel, Frank; De Bondt, Pieter; Buechel, Ronny R; Cuocolo, Alberto; van Eck-Smit, Berthe L F; Flotats, Albert; Hacker, Marcus; Hindorf, Cecilia; Kaufmann, Philip A; Lindner, Oliver; Ljungberg, Michael; Lonsdale, Markus; Manrique, Alain; Minarik, David; Scholte, Arthur J H A; Slart, Riemer H J A; Trägårdh, Elin; de Wit, Tim C; Hesse, Birger

    2015-11-01

    Since the publication of the European Association of Nuclear Medicine (EANM) procedural guidelines for radionuclide myocardial perfusion imaging (MPI) in 2005, many small and some larger steps of progress have been made, improving MPI procedures. In this paper, the major changes from the updated 2015 procedural guidelines are highlighted, focusing on the important changes related to new instrumentation with improved image information and the possibility to reduce radiation exposure, which is further discussed in relation to the recent developments of new International Commission on Radiological Protection (ICRP) models. Introduction of the selective coronary vasodilator regadenoson and the use of coronary CT-contrast agents for hybrid imaging with SPECT/CT angiography are other important areas for nuclear cardiology that were not included in the previous guidelines. A large number of minor changes have been described in more detail in the fully revised version available at the EANM home page: http://eanm.org/publications/guidelines/2015_07_EANM_FINAL_myocardial_perfusion_guideline.pdf .

  14. Potential value of serial cerebral SPECT scanning in the evaluation of psychiatric illness

    SciTech Connect

    Notardonato, H.; Gonzalez-Avilez, A.; Van Heertum, R.L.; O'Connell, R.A.; Yudd, A.P.

    1989-05-01

    Cerebral SPECT imaging has the potential to make an important contribution to clinical psychiatry. Cerebral SPECT scanning, stimulated by the work with PET, is readily available and much less expensive than PET. This paper reports a case demonstrating the potential value of cerebral SPECT scanning with I-123 IMP, specifically in the serial evaluation of a schizophrenic patient with auditory hallucinations. The initial scan revealed focal areas of increased uptake in the caudate nuclei of the basal ganglia, and in the right temporal lobe. After pharmacological treatment with clinical improvement, the follow-up SPECT scan demonstrated significant improvement in the distribution of the radiopharmaceutical.

  15. Evaluation of the use of freehand SPECT for sentinel node biopsy in early stage oral carcinoma.

    PubMed

    Heuveling, Derrek A; van Weert, Stijn; Karagozoglu, K Hakki; de Bree, Remco

    2015-03-01

    Inadequate intraoperative visualization of the sentinel node can hamper its harvest. Freehand SPECT is a 3D tomographic imaging modality based on the concepts of SPECT, which can be used for intraoperative visualization and navigation towards the sentinel node in order to improve its localization and removal during surgery. The use of freehand SPECT was evaluated during 66 sentinel node biopsy procedures in early stage oral cancer patients. Intraoperative detection of sentinel nodes was compared with preoperative identified sentinel nodes on lymphoscinitigraphic examination. Additional value of freehand SPECT was subjectively scored by the surgeon directly following the biopsy procedure. Freehand SPECT was able to detect 94% of sentinel nodes intraoperatively. Most sentinel nodes not detected (7 out of 9) were located in level I of the neck. Freehand SPECT appeared to be of additional value for facilitating the intraoperative detection of the sentinel node in 24% of procedures. The use of the freehand SPECT system is feasible in the intraoperative detection of sentinel nodes in early stage oral cancer. Freehand SPECT provides helpful information facilitating the SN biopsy procedure in a quarter of cases. However, freehand SPECT cannot detect all SNs which are located in the vicinity of the injection site. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Preliminary Characterization and In Vivo Studies of Structurally Identical 18F- and 125I-Labeled Benzyloxybenzenes for PET/SPECT Imaging of β-Amyloid Plaques

    PubMed Central

    Yang, Yanping; Zhang, Xiaoyang; Cui, Mengchao; Zhang, Jinming; Guo, Zhide; Li, Yesen; Zhang, Xianzhong; Dai, Jiapei; Liu, Boli

    2015-01-01

    With the assistance of molecular docking and 3D-QSAR models established previously, structurally identical 18F- and 125I-labeled benzyloxybenzene derivatives were designed to achieve the early detection of Aβ plaques by PET/SPECT imaging. In competition binding assay, ligands 7a and 12a displayed high binding affinities to Aβ42 aggregates with Ki values of 19.5 nM and 23.9 nM, respectively. Specific plaque labeling was observed on the in vitro autoradiography of brain sections from AD patients and Tg mice. In biodistribution, [125I]7a, [18F]7a, [125I]12a and [18F]12a all exhibited high initial brain uptakes (>5% ID/g at 2 min). [125I]7a and [125I]12a cleared fast from the normal brain regions, while corresponding [18F]7a and [18F]12a showed slow washout rates. Dynamic microPET/CT and microSPECT/CT imaging data in normal ICR mice were in accordance with in vivo biodistribution results. In vivo metabolism results indicated that the different clearance profiles between the structurally identical 18F- and 125I-labeled tracers could be attributed to different biochemical characteristics of the radiometabolites. Radioiodinated benzyloxybenzene derivatives exhibited good in vivo biostability in brain. Ex vivo autoradiography further confirmed the strong in vivo Aβ labeling ability of [125I]7a. These new fluorinated and iodinated benzyloxybenzenes can develop into PET/SPECT dual imaging agents targeting Aβ plaques. PMID:26170205

  17. Recent advances in cardiac SPECT instrumentation and system design.

    PubMed

    Smith, Mark F

    2013-08-01

    Recent advances in clinical cardiac SPECT instrumentation are reviewed from a systems perspective. New hardware technologies include pixelated scintillator and semiconductor detector elements; photodetectors such as position-sensitive photomultiplier tubes (PSPMT), avalanche photodiodes (APD) and silicon photomultipliers (SiPM); and novel cardiac collimation methods. There are new approaches for positioning detectors and controlling their motion during cardiac imaging. Software technology advances include iterative image reconstruction with modeling of Poisson statistics and depth-dependent collimator response. These new technologies enable faster acquisitions, the lowering of administered activity and radiation dose, and improved image resolution. Higher sensitivity collimators are a significant factor enabling faster acquisitions. Several clinical systems incorporating new technologies are discussed and different system designs can achieve similar performance. With detector elements such as APDs, SiPMs and semiconductors that are insensitive to magnetic fields, the potential for cardiac SPECT imagers that are MRI compatible opens up new frontiers in clinical cardiac research and patient care.

  18. Accuracy of quantitative reconstructions in SPECT/CT imaging

    NASA Astrophysics Data System (ADS)

    Shcherbinin, S.; Celler, A.; Belhocine, T.; van der Werf, R.; Driedger, A.

    2008-09-01

    The goal of this study was to determine the quantitative accuracy of our OSEM-APDI reconstruction method based on SPECT/CT imaging for Tc-99m, In-111, I-123, and I-131 isotopes. Phantom studies were performed on a SPECT/low-dose multislice CT system (Infinia-Hawkeye-4 slice, GE Healthcare) using clinical acquisition protocols. Two radioactive sources were centrally and peripherally placed inside an anthropometric Thorax phantom filled with non-radioactive water. Corrections for attenuation, scatter, collimator blurring and collimator septal penetration were applied and their contribution to the overall accuracy of the reconstruction was evaluated. Reconstruction with the most comprehensive set of corrections resulted in activity estimation with error levels of 3-5% for all the isotopes.

  19. Delayed redistribution in thallium 201 SPECT myocardial perfusion studies

    SciTech Connect

    Ziessman, H.A.; Keyes, J.W. Jr.; Fox, L.M.; Green, C.E.; Fox, S.M. )

    1989-11-01

    Stress {sup 201}Tl myocardial perfusion studies are useful in differentiating viable, reversibly ischemic from infarcted myocardium. A perfusion defect that shows redistribution 2 to 4 h after {sup 201}Tl injection is diagnostic of ischemia, while a fixed defect suggests infarction. However, occasional patients with a fixed defect at 4 h have redistribution at 24 h. This study evaluates the frequency and significance of this delayed redistribution with SPECT {sup 201}Tl. Patients with either no or incomplete redistribution at 4 h had repeat imaging 18 to 48 h later. Delayed redistribution was seen in 8/26 (31 percent). Four had incomplete and four had no redistribution at 4 h. Delayed redistribution with SPECT {sup 201}Tl is more common than generally appreciated, and we recommend delayed images in patients with fixed perfusion defects or incomplete redistribution at 4-h imaging, particularly in patients with previous infarctions for whom a revascularization procedure is being considered.

  20. SPECT study of regional cerebral blood flow in Alzheimer disease

    SciTech Connect

    Bonte, F.J.; Ross, E.D.; Chehabi, H.H.; Devous, M.D. Sr.

    1986-07-01

    A common cause of dementia in late midlife and old age is Alzheimer disease (AD), which affects more than one in 20 individuals over the age of 65. Past studies of regional cerebral blood flow (rCBF) in patients with AD here suggested blood flow abnormalities, but findings have differed. We have studied 37 patients diagnosed as having AD with inhalation and washout of /sup 133/Xe and single-photon emission computed tomography (SPECT), obtaining evidence of abnormal rCBF patterns in 19. Flow reductions were most common in the temporoparietal regions and were occasionally found in the frontal areas. Investigators using positron-emission tomography (PET) have identified similar findings with respect to rCBF and regional oxygen, glucose, and protein metabolism. The SPECT determination of rCBF, which gives information similar to that provided by PET, may assume importance in the diagnosis of AD and in the differential diagnosis of the dementias.

  1. Molecular Imaging of Hydrolytic Enzymes Using PET and SPECT

    PubMed Central

    Rempel, Brian P.; Price, Eric W.

    2017-01-01

    Hydrolytic enzymes are a large class of biological catalysts that play a vital role in a plethora of critical biochemical processes required to maintain human health. However, the expression and/or activity of these important enzymes can change in many different diseases and therefore represent exciting targets for the development of positron emission tomography (PET) and single-photon emission computed tomography (SPECT) radiotracers. This review focuses on recently reported radiolabeled substrates, reversible inhibitors, and irreversible inhibitors investigated as PET and SPECT tracers for imaging hydrolytic enzymes. By learning from the most successful examples of tracer development for hydrolytic enzymes, it appears that an early focus on careful enzyme kinetics and cell-based studies are key factors for identifying potentially useful new molecular imaging agents. PMID:28927325

  2. High-order total variation minimization for interior SPECT

    NASA Astrophysics Data System (ADS)

    Yang, Jiansheng; Yu, Hengyong; Jiang, Ming; Wang, Ge

    2012-01-01

    Recently, we developed an approach for solving the computed tomography (CT) interior problem based on the high-order TV (HOT) minimization, assuming that a region-of-interest (ROI) is piecewise polynomial. In this paper, we generalize this finding from the CT field to the single-photon emission computed tomography (SPECT) field, and prove that if an ROI is piecewise polynomial, then the ROI can be uniquely reconstructed from the SPECT projection data associated with the ROI through the HOT minimization. Also, we propose a new formulation of HOT, which has an explicit formula for any n-order piecewise polynomial function, while the original formulation has no explicit formula for n ⩾ 2. Finally, we verify our theoretical results in numerical simulation, and discuss relevant issues.

  3. A novel SPECT camera for molecular imaging of the prostate

    NASA Astrophysics Data System (ADS)

    Cebula, Alan; Gilland, David; Su, Li-Ming; Wagenaar, Douglas; Bahadori, Amir

    2011-10-01

    The objective of this work is to develop an improved SPECT camera for dedicated prostate imaging. Complementing the recent advancements in agents for molecular prostate imaging, this device has the potential to assist in distinguishing benign from aggressive cancers, to improve site-specific localization of cancer, to improve accuracy of needle-guided prostate biopsy of cancer sites, and to aid in focal therapy procedures such as cryotherapy and radiation. Theoretical calculations show that the spatial resolution/detection sensitivity of the proposed SPECT camera can rival or exceed 3D PET and further signal-to-noise advantage is attained with the better energy resolution of the CZT modules. Based on photon transport simulation studies, the system has a reconstructed spatial resolution of 4.8 mm with a sensitivity of 0.0001. Reconstruction of a simulated prostate distribution demonstrates the focal imaging capability of the system.

  4. Infective endocarditis detection through SPECT/CT images digital processing

    NASA Astrophysics Data System (ADS)

    Moreno, Albino; Valdés, Raquel; Jiménez, Luis; Vallejo, Enrique; Hernández, Salvador; Soto, Gabriel

    2014-03-01

    Infective endocarditis (IE) is a difficult-to-diagnose pathology, since its manifestation in patients is highly variable. In this work, it was proposed a semiautomatic algorithm based on SPECT images digital processing for the detection of IE using a CT images volume as a spatial reference. The heart/lung rate was calculated using the SPECT images information. There were no statistically significant differences between the heart/lung rates values of a group of patients diagnosed with IE (2.62+/-0.47) and a group of healthy or control subjects (2.84+/-0.68). However, it is necessary to increase the study sample of both the individuals diagnosed with IE and the control group subjects, as well as to improve the images quality.

  5. In vitro and in vivo evaluation of iodine-123-Ro 16-0154: A new imaging agent for SPECT investigations of benzodiazepine receptors

    SciTech Connect

    Beer, H.F.; Blaeuenstein, P.A.H.; Hasler, P.H.; Delaloye, B.; Riccabona, G.; Bangerl, I.; Hunkeler, W.; Bonetti, E.P.; Pieri, L.; Richards, J.G. )

    1990-06-01

    The flumazenil analogue, Ro 16-0154, a benzodiazepine partial inverse agonist, has been labeled by halogen exchange to enable SPECT investigations of central benzodiazepine receptors in the human brain. The purified {sup 123}I-Ro 16-0154 was found to be stable in rat brain preparations and to be metabolized in rat liver preparations. Its pharmacologic properties were comparable to those of flumazenil. The biodistribution in rats (1 hr postinjection) resulted in a high brain-to-blood ratio of 16. Clinical studies revealed images of the benzodiazepine receptor density in the brain. Since the receptor labeling was markedly reduced by injection of flumazenil, it was considered to be specific. Storage defects due to pathologic cerebral blood flow and changed receptor density were detected; this shows the potential usefulness of the substance for diagnostic purposes, e.g., the differential diagnosis of various forms of epilepsy.

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

    PubMed Central

    Miura, You; Seto, Akira; Kanazawa, Minoru; Nagata, Makoto

    2016-01-01

    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. PMID:27478660

  7. [MRI and SPECT findings in a case of metronidazole-induced reversible acute cerebellar ataxia].

    PubMed

    Takase, Kei-ichiro; Santa, Yo; Ohta, Sumio; Yoshimura, Takeo

    2005-05-01

    A 69-year-old man was referred to our department because of acute onset nausea, vomiting, dysphagia, dysarthria and gait disturbance. He had a 50-day-history of amebic dysentery and had been treated with 1,500 mg metronidazole per day. Neurological examination revealed dysphagia, ataxic speech, ataxia of the left extremities and the trunk, and hyperactive deep tendon reflexes in all extremities. Sensory impairment of all modalities was apparent in a glove and stocking pattern, with mild paresthesia. Brain MRI showed T2 high signal lesions in the bilateral cerebellar dentate nuclei, more markedly on the left. On brain SPECT, obvious low blood perfusion was observed in the left cerebellar hemisphere. These findings well explained the ataxia of the left limbs. One month after discontinuing metronidazole, the cerebellar ataxia, dysphagia and MRI abnormalities completely cleared. Therefore, central nervous system damage induced by metronidazole is considered reversible. In spite of the presence of the MRI lesion in the right dentate nucleus, the patient had no ataxia of the right extremities and there was no hypoperfusion in the right cerebellar hemisphere. Thus, metronidazole does not appear to have a direct neurotoxic effect on the central nervous system. On the other hand, nerve conduction studies showed axonal polyneuropathy, which was not improved one month after cessation of the drug; thus metronidazole seems to exert more damage on peripheral nerves.

  8. Human biodistribution and dosimetry of the SPECT benzodiazepine receptor radioligand iodine-123-iomazenil

    SciTech Connect

    Dey, H.M.; Seibyl, J.P.; Stubbs, J.B.

    1994-03-01

    SPECT imaging of the brain with [{sup 123}I]iomazenil has shown avid uptake of the radioligand in a distribution consistent with benzodiazepine receptor binding. The purposes of this study were to measure the whole-body distribution of activity following i.v. adminstration of [{sup 123}I]iomazenil and to evaluate the resulting organ radiation burdens. Serial total body scans were obtained in healthy volunteers after thyroid blockade and demonstrated avid brain uptake of radioligand. Abdominal imaging showed significant activity retention within the urinary and gastrointestinal tracts consistent with excretion via these routes. Absorbed dose to the urinary bladder was calculated to be 0.19 mGy/MBq, to the lower large intestine 0.079 mGy/MBq, to the upper large intestine 0.066 mGy/MBq, and to the thyroid 0.063 mGy/MBq. Thyroid uptake may in part have represented binding to benzodiazepine receptors, since radioligand binding to tissue homogenates prepared from human thyroid showed the presence of benzodiazepine binding sites. 20 refs., 4 figs., 2 tabs.

  9. PET and SPECT Radiotracers to Assess Function and Expression of ABC Transporters in Vivo

    PubMed Central

    Mairinger, Severin; Erker, Thomas; Müller, Markus; Langer, Oliver

    2013-01-01

    Adenosine triphosphate-binding cassette (ABC) transporters, such as P-glycoprotein (Pgp, ABCB1), breast cancer resistance protein (BCRP, ABCG2) and multidrug resistance-associated proteins (MRPs) are expressed in high concentrations at various physiological barriers (e.g. blood-brain barrier, blood-testis barrier, blood-tumor barrier), where they impede the tissue accumulation of various drugs by active efflux transport. Changes in ABC transporter expression and function are thought to be implicated in various diseases, such as cancer, epilepsy, Alzheimer’s and Parkinson’s disease. The availability of a non-invasive imaging method which allows for measuring ABC transporter function or expression in vivo would be of great clinical use in that it could facilitate the identification of those patients that would benefit from treatment with ABC transporter modulating drugs. To date three different kinds of imaging probes have been described to measure ABC transporters in vivo: i) radiolabelled transporter substrates ii) radiolabelled transporter inhibitors and iii) radiolabelled prodrugs which are enzymatically converted into transporter substrates in the organ of interest (e.g. brain). The design of new imaging probes to visualize efflux transporters is inter alia complicated by the overlapping substrate recognition pattern of different ABC transporter types. The present article will describe currently available ABC transporter radiotracers for positron emission tomography (PET) and single-photon emission computed tomography (SPECT) and critically discuss strengths and limitations of individual probes and their potential clinical applications. PMID:21434859

  10. Compact CT/SPECT Small-Animal Imaging System

    PubMed Central

    Kastis, George A.; Furenlid, Lars R.; Wilson, Donald W.; Peterson, Todd E.; Barber, H. Bradford; Barrett, Harrison H.

    2015-01-01

    We have developed a dual-modality CT/SPECT imaging system for small-animal imaging applications. The X-ray system comprises a commercially available micro-focus X-ray tube and a CCD-based X-ray camera. X-ray transmission measurements are performed based on cone-beam geometry. Individual projections are acquired by rotating the animal about a vertical axis in front of the CCD detector. A high-resolution CT image is obtained after reconstruction using an ordered subsets-expectation maximization (OS-EM) reconstruction algorithm. The SPECT system utilizes a compact semiconductor camera module previously developed in our group. The module is mounted perpendicular to the X-ray tube/CCD combination. It consists of a 64×64 pixellated CdZnTe detector and a parallel-hole tungsten collimator. The field of view is 1 square inch. Planar projections for SPECT reconstruction are obtained by rotating the animal in front of the detector. Gamma-ray and X-ray images are presented of phantoms and mice. Procedures for merging the anatomical and functional images are discussed. PMID:26538684

  11. SVD-based evaluation of multiplexing in multipinhole SPECT systems.

    PubMed

    Jorgensen, Aaron K; Zeng, Gengsheng L

    2008-01-01

    Multipinhole SPECT system design is largely a trial-and-error process. General principles can give system designers a general idea of how a system with certain characteristics will perform. However, the specific performance of any particular system is unknown before the system is tested. The development of an objective evaluation method that is not based on experimentation would facilitate the optimization of multipinhole systems. We derive a figure of merit for prediction of SPECT system performance based on the entire singular value spectrum of the system. This figure of merit contains significantly more information than the condition number of the system, and is therefore more revealing of system performance. This figure is then compared with simulated results of several SPECT systems and is shown to correlate well to the results of the simulations. The proposed figure of merit is useful for predicting system performance, but additional steps could be taken to improve its accuracy and applicability. The limits of the proposed method are discussed, and possible improvements to it are proposed.

  12. Dynamic heart-in-thorax phantom for functional SPECT

    SciTech Connect

    Celler, A.; Lyster, D.; Farncombe, T.

    1996-12-31

    We have designed and built a dynamic heart-in-thorax phantom to be used as a primary tool during the experimental verification of the performance of the quantitative dynamic functional imaging method we are developing for standard rotating single photon emission computed tomography (SPECT) cameras. The phantom consists of two independent parts (i) a dynamic heart model with the possibility of mounting {open_quotes}defects{close_quotes} inside it and (ii) a non-uniform thorax model with lungs and spinal cord, and uses the fact that the washout of a tracer by dilution is governed by a linear first order equation, the same type of equation as is used to model time-activity distribution in myocardial viability studies. Tests of the dynamic performance of the phantom in planar scanning mode have confirmed the validity of these assumptions. Also the preliminary results obtained in SPECT mode show that the values of characteristic times could be experimentally determined and that these values agreed well with the values preset on the phantom. We consider that the phantom is ready for extensive use in studies into development of the dynamic SPECT method.

  13. Anatomy guided automated SPECT renal seed point estimation

    NASA Astrophysics Data System (ADS)

    Dwivedi, Shekhar; Kumar, Sailendra

    2010-04-01

    Quantification of SPECT(Single Photon Emission Computed Tomography) images can be more accurate if correct segmentation of region of interest (ROI) is achieved. Segmenting ROI from SPECT images is challenging due to poor image resolution. SPECT is utilized to study the kidney function, though the challenge involved is to accurately locate the kidneys and bladder for analysis. This paper presents an automated method for generating seed point location of both kidneys using anatomical location of kidneys and bladder. The motivation for this work is based on the premise that the anatomical location of the bladder relative to the kidneys will not differ much. A model is generated based on manual segmentation of the bladder and both the kidneys on 10 patient datasets (including sum and max images). Centroid is estimated for manually segmented bladder and kidneys. Relatively easier bladder segmentation is followed by feeding bladder centroid coordinates into the model to generate seed point for kidneys. Percentage error observed in centroid coordinates of organs from ground truth to estimated values from our approach are acceptable. Percentage error of approximately 1%, 6% and 2% is observed in X coordinates and approximately 2%, 5% and 8% is observed in Y coordinates of bladder, left kidney and right kidney respectively. Using a regression model and the location of the bladder, the ROI generation for kidneys is facilitated. The model based seed point estimation will enhance the robustness of kidney ROI estimation for noisy cases.

  14. Evaluation of attenuation corrections using Monte Carlo simulated lung SPECT

    NASA Astrophysics Data System (ADS)

    Gustafsson, Agnetha; Bake, Björn; Jacobsson, Lars; Johansson, Åke; Ljungberg, Michael; Moonen, Michaela

    1998-08-01

    SPECT (single photon emission computed tomography) images are distorted by photon attenuation. The effect is complex in the thoracic region due to different tissue densities. This study compares the effect on the image homogeneity of two different methods of attenuation correction in lung SPECT; one pre-processing and one post-processing method. This study also investigates the impact of attenuation correction parameters such as lung contour, body contour, density of the lung tissue and effective attenuation coefficient. The Monte Carlo technique was used to simulate SPECT studies of a digital thorax phantom containing a homogeneous activity distribution in the lung. Homogeneity in reconstructed images was calculated as the coefficient of variation (CV). The isolated effect of the attenuation correction was assessed by normalizing pixel values from the attenuation corrected lung by pixel values from the lung with no attenuation effects. Results show that the CV decreased from 12.8% with no attenuation correction to 4.4% using the post-processing method and true densities in the thoracic region. The impact of variations in the definition of the body contour was found to be marginal while the corresponding effect of variations in the lung contour was substantial.

  15. 3D SPECT/CT fusion using image data projection of bone SPECT onto 3D volume-rendered CT images: feasibility and clinical impact in the diagnosis of bone metastasis.

    PubMed

    Ogata, Yuji; Nakahara, Tadaki; Ode, Kenichi; Matsusaka, Yohji; Katagiri, Mari; Iwabuchi, Yu; Itoh, Kazunari; Ichimura, Akira; Jinzaki, Masahiro

    2017-05-01

    We developed a method of image data projection of bone SPECT into 3D volume-rendered CT images for 3D SPECT/CT fusion. The aims of our study were to evaluate its feasibility and clinical usefulness. Whole-body bone scintigraphy (WB) and SPECT/CT scans were performed in 318 cancer patients using a dedicated SPECT/CT systems. Volume data of bone SPECT and CT were fused to obtain 2D SPECT/CT images. To generate our 3D SPECT/CT images, colored voxel data of bone SPECT were projected onto the corresponding location of the volume-rendered CT data after a semi-automatic bone extraction. Then, the resultant 3D images were blended with conventional volume-rendered CT images, allowing to grasp the three-dimensional relationship between bone metabolism and anatomy. WB and SPECT (WB + SPECT), 2D SPECT/CT fusion, and 3D SPECT/CT fusion were evaluated by two independent reviewers in the diagnosis of bone metastasis. The inter-observer variability and diagnostic accuracy in these three image sets were investigated using a four-point diagnostic scale. Increased bone metabolism was found in 744 metastatic sites and 1002 benign changes. On a per-lesion basis, inter-observer agreements in the diagnosis of bone metastasis were 0.72 for WB + SPECT, 0.90 for 2D SPECT/CT, and 0.89 for 3D SPECT/CT. Receiver operating characteristic analyses for the diagnostic accuracy of bone metastasis showed that WB + SPECT, 2D SPECT/CT, and 3D SPECT/CT had an area under the curve of 0.800, 0.983, and 0.983 for reader 1, 0.865, 0.992, and 0.993 for reader 2, respectively (WB + SPECT vs. 2D or 3D SPECT/CT, p < 0.001; 2D vs. 3D SPECT/CT, n.s.). The durations of interpretation of WB + SPECT, 2D SPECT/CT, and 3D SPECT/CT images were 241 ± 75, 225 ± 73, and 182 ± 71 s for reader 1 and 207 ± 72, 190 ± 73, and 179 ± 73 s for reader 2, respectively. As a result, it took shorter time to read 3D SPECT/CT images than 2D SPECT/CT (p < 0.0001) or WB + SPECT

  16. A stripe sign on 99mTc-Technegas SPECT in pulmonary emphysema.

    PubMed

    Suga, Kazuyoshi; Kawakami, Yasuhiko; Iwanaga, Hideyuki; Tokuda, Osamu; Matsunaga, Naofumi

    2008-06-01

    By focusing on a stripe sign (interposed preserved radioactivity between central defects and pleural surface of the lung), the cross-sectional ventilation difference between the central and peripheral lung in pulmonary emphysema was evaluated on Tc-Technegas SPECT, and compared with other forms of chronic obstructive pulmonary disease (COPD). Technegas and perfusion SPECT were performed in 47 patients with relatively advanced emphysema, 15 patients with other forms of COPD without alveolar destruction and six controls. The presence or absence of a stripe sign was evaluated at upper, middle and lower lung zones on both SPECT. At stripe sign-positive lung zones on Technegas SPECT in pulmonary emphysema, the pattern of low attenuation areas (LAAs) distribution on X-ray CT was also evaluated. Of the total of 282 lung zones in patients with emphysema, a stripe sign was positive on Technegas SPECT at 153 (54.2%) zones in 27 (57.4%) patients, although less frequently positive on perfusion SPECT at 166 (58.8%) zones in 30 (63.8%) patients. This sign was negative on Technegas SPECT throughout the stripe sign-negative zones on perfusion SPECT. Throughout the lung zones in controls and patients with other forms of COPD, this sign was negative both on Technegas and perfusion SPECT. On X-ray CT, 124 (81%) of 153 stripe-positive lung zones on Technegas SPECT in pulmonary emphysema showed central lung-dominant LAA. In contrast to other forms of COPD, a stripe sign was frequently positive on Technegas SPECT in relatively advanced emphysema, with central-lung dominant LAA on X-ray CT. Relative preservation of peripheral lung ventilation seems to be a characteristic feature of this disease, indicating a lower susceptibility of the peripheral lung for alveolar destruction.

  17. Spatial resolution is dependent on image content for SPECT with iterative reconstruction incorporating distance dependent resolution (DDR) correction.

    PubMed

    Badger, Daniel; Barnden, Leighton

    2014-09-01

    The aim of this study is to determine the dependence of single photon emission computed tomography (SPECT) spatial resolution on the content of images for iterative reconstruction with distance dependent resolution (DDR) correction. An experiment was performed using a perturbation technique to measure change in resolution of line sources in simple and complex images with iterative reconstruction with increasing iteration. Projections of the line sources were reconstructed alone and again after the addition of projections of a uniform flood or a complex phantom. An alternative experiment used images of a realistic brain phantom and evaluated an effective spatial resolution by matching the images to the digital version of the phantom convolved with 3D Gaussian kernels. The experiments were performed using ordered subset expectation maximisation iterative reconstruction with and without the use of DDR correction. The results show a significant difference in reconstructed resolution between images of line sources depending on the content of the added image. The full width at half maximum of images of a line source reconstructed using DDR correction increased by 20-30 % when the added image was complex. Without DDR this difference was much smaller and disappeared with increasing iteration. Reported SPECT resolution should be taken as indicative only with regard to clinical imaging if the measurement is made using a point or line source alone and an iterative reconstruction algorithm is used.

  18. Nuclear myocardial perfusion imaging using thallium-201 with a novel multifocal collimator SPECT/CT: IQ-SPECT versus conventional protocols in normal subjects.

    PubMed

    Matsuo, Shinro; Nakajima, Kenichi; Onoguchi, Masahisa; Wakabayash, Hiroshi; Okuda, Koichi; Kinuya, Seigo

    2015-06-01

    A novel multifocal collimator, IQ-SPECT (Siemens) consists of SMARTZOOM, cardio-centric and 3D iterative SPECT reconstruction and makes it possible to perform MPI scans in a short time. The aims are to delineate the normal uptake in thallium-201 ((201)Tl) SPECT in each acquisition method and to compare the distribution between new and conventional protocol, especially in patients with normal imaging. Forty patients (eight women, mean age of 75 years) who underwent myocardial perfusion imaging were included in the study. All patients underwent one-day protocol perfusion scan after an adenosine-stress test and at rest after administering (201)Tl and showed normal results. Acquisition was performed on a Symbia T6 equipped with a conventional dual-headed gamma camera system (Siemens ECAM) and with a multifocal SMARTZOOM collimator. Imaging was performed with a conventional system followed by IQ-SPECT/computed tomography (CT). Reconstruction was performed with or without X-ray CT-derived attenuation correction (AC). Two nuclear physicians blinded to clinical information interpreted all myocardial perfusion images. A semi-quantitative myocardial perfusion was analyzed by a 17-segment model with a 5-point visual scoring. The uptake of each segment was measured and left ventricular functions were analyzed by QPS software. IQ-SPECT provided good or excellent image quality. The quality of IQ-SPECT images without AC was similar to those of conventional LEHR study. Mid-inferior defect score (0.3 ± 0.5) in the conventional LEHR study was increased significantly in IQ-SPECT with AC (0 ± 0). IQ-SPECT with AC improved the mid-inferior decreased perfusion shown in conventional images. The apical tracer count in IQ-SPECT with AC was decreased compared to that in LEHR (0.1 ± 0.3 vs. 0.5 ± 0.7, p < 0.05). The left ventricular ejection fraction from IQ-SPECT was significantly higher than that from the LEHR collimator (p = 0.0009). The images of IQ-SPECT acquired in a

  19. Direction-dependent localization errors in SPECT images

    SciTech Connect

    Roper, Justin; Bowsher, James; Yin Fangfang

    2010-09-15

    Purpose: Single photon emission computed tomography (SPECT) is being investigated for imaging inside radiation therapy treatment rooms to localize biological targets. Here, computer simulations were used to analyze locational and directional dependencies in localization errors and to assess the effects of spatial resolution modeling and observer normalization on localization performance. Methods: SPECT images of the XCAT phantom, containing 12 hot tumors, were reconstructed with detector response function compensation (DRC) and without DRC (nDRC). Numerical observers were forced to select the most suspicious tumor location, using normalized cross correlation (NXC) or un-normalized cross correlation (XC), from 3 cm diameter search volumes that each contained only one tumor. For each tumor site, localization was optimized as a function of the iteration number and postreconstruction smoothing. Localization error, the distance between true and estimated tumor positions, was calculated across the ensembles of 80 images. Direction-dependent localization bias and precision were estimated from the image ensemble. Results: For the six superficial tumors in close proximity to the detector trajectory, mean localization errors were <2 mm and were lowest or comparable using DRC-NXC, though differences from DRC-XC and nDRC-NXC were not statistically significant. DRC-NXC did provide statistically significantly better localization than nDRC-XC for five of these six tumors. At the other six sites where attenuation was more severe and the distance was generally greater between the tumor and detector, DRC typically did not show better localization than nDRC. Observer normalization improved the localization substantially for a tumor near the hotter heart. Localization errors were anisotropic and dependent on tumor location relative to the detector trajectory. Conclusions: This computer-simulation study compared localization performance for normalized and un-normalized numerical

  20. A parallel Monte Carlo code for planar and SPECT imaging: implementation, verification and applications in (131)I SPECT.

    PubMed

    Dewaraja, Yuni K; Ljungberg, Michael; Majumdar, Amitava; Bose, Abhijit; Koral, Kenneth F

    2002-02-01

    This paper reports the implementation of the SIMIND Monte Carlo code on an IBM SP2 distributed memory parallel computer. Basic aspects of running Monte Carlo particle transport calculations on parallel architectures are described. Our parallelization is based on equally partitioning photons among the processors and uses the Message Passing Interface (MPI) library for interprocessor communication and the Scalable Parallel Random Number Generator (SPRNG) to generate uncorrelated random number streams. These parallelization techniques are also applicable to other distributed memory architectures. A linear increase in computing speed with the number of processors is demonstrated for up to 32 processors. This speed-up is especially significant in Single Photon Emission Computed Tomography (SPECT) simulations involving higher energy photon emitters, where explicit modeling of the phantom and collimator is required. For (131)I, the accuracy of the parallel code is demonstrated by comparing simulated and experimental SPECT images from a heart/thorax phantom. Clinically realistic SPECT simulations using the voxel-man phantom are carried out to assess scatter and attenuation correction.

  1. Brain perfusion asymmetry in patients with oral somatic delusions.

    PubMed

    Umezaki, Yojiro; Katagiri, Ayano; Watanabe, Motoko; Takenoshita, Miho; Sakuma, Tomomi; Sako, Emi; Sato, Yusuke; Toriihara, Akira; Uezato, Akihito; Shibuya, Hitoshi; Nishikawa, Toru; Motomura, Haruhiko; Toyofuku, Akira

    2013-06-01

    Oral cenesthopathy is a somatic delusion or hallucination involving the oral area and is categorized as a delusional disorder, somatic type. The pathophysiology of this intractable condition remains obscure. In this study, we clarified the pathophysiology of oral cenesthopathy by evaluating regional brain perfusion. We performed single photon emission computed tomography (SPECT) using (99m)Tc-ethylcysteinate dimer in 16 subjects (cenesthopathy:control = 8:8). The SPECT images were visually assessed qualitatively, and quantitative analyses were also performed using a three-dimensional stereotactic region-of-interest template. The visual assessment revealed a right > left perfusion asymmetry in broad areas of the brain among the patients. The quantitative analysis confirmed that the regional cerebral blood flow values on the right side were significantly larger than those on the left side for most areas of the brain in the patients. A comparison of the R/(R + L) ratios in both groups confirmed the significant brain perfusion asymmetry between the two sides in the callosomarginal, precentral, and temporal regions in the patients. Qualitative evaluation of the SPECT images revealed right > left brain perfusion asymmetry in broad regions of the brain. Moreover, the quantitative analyses confirmed the perfusion asymmetry between the two sides in the frontal and temporal areas. Those may provide the key for elucidation of the pathophysiology of oral cenesthopathy.

  2. Design of a Multi-Pinhole Collimator for I-123 DaTscan Imaging on Dual-Headed SPECT Systems in Combination with a Fan-Beam Collimator.

    PubMed

    King, Michael A; Mukherjee, Joyeeta M; Könik, Arda; Zubal, I George; Dey, Joyoni; Licho, Robert

    2016-02-01

    For the 2011 FDA approved Parkinson's Disease (PD) SPECT imaging agent I-123 labeled DaTscan, the volume of interest (VOI) is the interior portion of the brain. However imaging of the occipital lobe is also required with PD for calculation of the striatal binding ratio (SBR), a parameter of significance in early diagnosis, differentiation of PD from other disorders with similar clinical presentations, and monitoring progression. Thus we propose the usage of a combination of a multi-pinhole (MPH) collimator on one head of the SPECT system and a fan-beam on the other. The MPH would be designed to provide high resolution and sensitivity for imaging of the interior portion of the brain. The fan-beam collimator would provide lower resolution but complete sampling of the brain addressing data sufficiency and allowing a volume-of-interest to be defined over the occipital lobe for calculation of SBR's. Herein we focus on the design of the MPH component of the combined system. Combined reconstruction will be addressed in a subsequent publication. An analysis of 46 clinical DaTscan studies was performed to provide information to define the VOI, and design of a MPH collimator to image this VOI. The system spatial resolution for the MPH was set to 4.7 mm, which is comparable to that of clinical PET systems, and significantly smaller than that of fan-beam collimators employed in SPECT. With this set, we compared system sensitivities for three aperture array designs, and selected the 3 × 3 array due to it being the highest of the three. The combined sensitivity of the apertures for it was similar to that of an ultra-high resolution fan-beam (LEUHRF) collimator, but smaller than that of a high-resolution fan-beam collimator (LEHRF). On the basis of these results we propose the further exploration of this design through simulations, and the development of combined MPH and fan-beam reconstruction.

  3. Design of a Multi-Pinhole Collimator for I-123 DaTscan Imaging on Dual-Headed SPECT Systems in Combination with a Fan-Beam Collimator

    NASA Astrophysics Data System (ADS)

    King, Michael A.; Mukherjee, Joyeeta M.; Könik, Arda; Zubal, I. George; Dey, Joyoni; Licho, Robert

    2016-02-01

    For the 2011 FDA approved Parkinson's Disease (PD) SPECT imaging agent I-123 labeled DaTscan, the volume of interest (VOI) is the interior portion of the brain. However imaging of the occipital lobe is also required with PD for calculation of the striatal binding ratio (SBR), a parameter of significance in early diagnosis, differentiation of PD from other disorders with similar clinical presentations, and monitoring progression. Thus we propose the usage of a combination of a multi-pinhole (MPH) collimator on one head of the SPECT system and a fan-beam on the other. The MPH would be designed to provide high resolution and sensitivity for imaging of the interior portion of the brain. The fan-beam collimator would provide lower resolution but complete sampling of the brain addressing data sufficiency and allowing a volume-of-interest to be defined over the occipital lobe for calculation of SBR's. Herein we focus on the design of the MPH component of the combined system. Combined reconstruction will be addressed in a subsequent publication. An analysis of 46 clinical DaTscan studies was performed to provide information to define the VOI, and design of a MPH collimator to image this VOI. The system spatial resolution for the MPH was set to 4.7 mm, which is comparable to that of clinical PET systems, and significantly smaller than that of fan-beam collimators employed in SPECT. With this set, we compared system sensitivities for three aperture array designs, and selected the 3 × 3 array due to it being the highest of the three. The combined sensitivity of the apertures for it was similar to that of an ultra-high resolution fan-beam (LEUHRF) collimator, but smaller than that of a high-resolution fan-beam collimator (LEHRF). On the basis of these results we propose the further exploration of this design through simulations, and the development of combined MPH and fan-beam reconstruction.

  4. A Monte Carlo investigation of dual-planar circular-orbit cone-beam SPECT

    NASA Astrophysics Data System (ADS)

    Lalush, David S.; Di Meo, Andrew J.

    2002-12-01

    We use Monte Carlo simulations to study the imaging properties of a design for a dual-planar cone-beam (DPCB) single-photon emission computed tomography (SPECT) system. A dual-planar system uses a dual-camera SPECT system and two cone-beam collimators with foci in different axial planes to increase the effective axial field of view (FOV). We simulated nearly noise-free projection data from a computerized brain phantom and a phantom consisting of a series of points. Four configurations were simulated: parallel-beam low-energy high-resolution (LEHR) as a standard for comparison and DPCB at three radii of rotation (ROR) corresponding to the smallest, average and largest ROR required to clear patients' shoulders based on ergonomic data. We compared global measures of average resolution and total acquired counts for the four configurations. We also estimated local spatial frequency response for reconstructions of point sources. Finally, we estimated a local noise power spectrum by simulating 1000 noise realizations of the brain phantom and estimating a local noise covariance at selected points. The noise power spectra were used to estimate spectral signal to noise ratio (SNR) for each configuration. The resolution in the reconstructed image space ranges from 7.2 mm full-width at half-maximum (FWHM) at the minimum ROR to 9.4 mm FWHM at the maximum ROR. The efficiency is inversely related, ranging from 1.5 times that of parallel LEHR at minimum ROR to 2.5 times that of LEHR at maximum ROR. Estimates of system frequency response roughly correspond to the global resolution estimates, but the cone-beam techniques exhibit an unusual secondary peak in the axial-direction response. Estimates of spectral SNR show that the cone-beam configurations almost always result in higher SNR at all spatial frequencies regardless of ROR. The very largest ROR may be an exception. A larger ROR results in significantly higher SNR for low spatial frequencies with small reductions in SNR for mid

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

    PubMed

    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. SPECT assay of radiolabeled monoclonal antibodies. Final performance report, March 1992--November 1995

    SciTech Connect

    Jaszczak, R.J.

    1995-12-01

    Research is described in the following areas: development and evaluation quantitatively of reconstruction algorithms with improved compensations for attenuation, scatter, and geometric collimator response; evaluation of single photon emission computed tomography (SPECT) quantification of iodine 123 and astatine 211; and the development and evaluation of SPECT pinhole imaging for low and medium energy photons.

  7. NOTE: Implementation of angular response function modeling in SPECT simulations with GATE

    NASA Astrophysics Data System (ADS)

    Descourt, P.; Carlier, T.; Du, Y.; Song, X.; Buvat, I.; Frey, E. C.; Bardies, M.; Tsui, B. M. W.; Visvikis, D.

    2010-05-01

    Among Monte Carlo simulation codes in medical imaging, the GATE simulation platform is widely used today given its flexibility and accuracy, despite long run times, which in SPECT simulations are mostly spent in tracking photons through the collimators. In this work, a tabulated model of the collimator/detector response was implemented within the GATE framework to significantly reduce the simulation times in SPECT. This implementation uses the angular response function (ARF) model. The performance of the implemented ARF approach has been compared to standard SPECT GATE simulations in terms of the ARF tables' accuracy, overall SPECT system performance and run times. Considering the simulation of the Siemens Symbia T SPECT system using high-energy collimators, differences of less than 1% were measured between the ARF-based and the standard GATE-based simulations, while considering the same noise level in the projections, acceleration factors of up to 180 were obtained when simulating a planar 364 keV source seen with the same SPECT system. The ARF-based and the standard GATE simulation results also agreed very well when considering a four-head SPECT simulation of a realistic Jaszczak phantom filled with iodine-131, with a resulting acceleration factor of 100. In conclusion, the implementation of an ARF-based model of collimator/detector response for SPECT simulations within GATE significantly reduces the simulation run times without compromising accuracy.

  8. Constrictive pericarditis causing a positive TI-201 SPECT stress test for myocardial ischemia

    SciTech Connect

    Matthews, R.J.; Lightfoote, J.; Grusd, R.S. )

    1990-08-01

    A case of constritive pericarditis was demonstrated by a positive thallium SPECT stress test for myocardial ischemia. After pericardiectomy, the repeat thallium stress test was normal. The disappearance of the criteria for a positive test suggests that constrictive pericarditis can cause myocardial ischemia, which can be demonstrated by thallium SPECT stress testing.

  9. Implementation of Angular Response Function modeling in SPECT simulations with GATE

    PubMed Central

    Descourt, P; Carlier, T; Du, Y; Song, X; Buvat, I; Frey, E C; Bardies, M; Tsui, B M W; Visvikis, D

    2010-01-01

    Among Monte Carlo simulation codes in medical imaging, the GATE simulation platform is widely used today given its flexibility and accuracy, despite long run times, which in SPECT simulations, is mostly spent in tracking photons through the collimators. In this work, a tabulated model of the collimator/detector response was implemented within the GATE framework to significantly reduce the simulation times in SPECT. This implementation uses the Angular Response Function (ARF) model. The performance of the implemented ARF approach has been compared to standard SPECT GATE simulations in terms of the ARF tables' accuracy, overall SPECT system performance and run times. Considering the simulation of the Siemens Symbia T SPECT system using high-energy collimators, differences of less than 1% were measured between the ARF based and the standard GATE based simulations, while considering the same noise level in the projections, acceleration factors of up to 180 were obtained when simulating a planar 364keV source seen with the same SPECT system. The ARF-based and the standard GATE simulation results also agreed very well when considering a 4-head SPECT simulation of a realistic Jaszczak phantom filled with iodine-131, with a resulting acceleration factor of 100. In conclusion, the implementation of an ARF-based model of collimator/detector response for SPECT simulations within GATE significantly reduces the simulation run times without compromising accuracy. PMID:20393239

  10. Implementation of angular response function modeling in SPECT simulations with GATE.

    PubMed

    Descourt, P; Carlier, T; Du, Y; Song, X; Buvat, I; Frey, E C; Bardies, M; Tsui, B M W; Visvikis, D

    2010-05-07

    Among Monte Carlo simulation codes in medical imaging, the GATE simulation platform is widely used today given its flexibility and accuracy, despite long run times, which in SPECT simulations are mostly spent in tracking photons through the collimators. In this work, a tabulated model of the collimator/detector response was implemented within the GATE framework to significantly reduce the simulation times in SPECT. This implementation uses the angular response function (ARF) model. The performance of the implemented ARF approach has been compared to standard SPECT GATE simulations in terms of the ARF tables' accuracy, overall SPECT system performance and run times. Considering the simulation of the Siemens Symbia T SPECT system using high-energy collimators, differences of less than 1% were measured between the ARF-based and the standard GATE-based simulations, while considering the same noise level in the projections, acceleration factors of up to 180 were obtained when simulating a planar 364 keV source seen with the same SPECT system. The ARF-based and the standard GATE simulation results also agreed very well when considering a four-head SPECT simulation of a realistic Jaszczak phantom filled with iodine-131, with a resulting acceleration factor of 100. In conclusion, the implementation of an ARF-based model of collimator/detector response for SPECT simulations within GATE significantly reduces the simulation run times without compromising accuracy.

  11. A comparison of MR-based attenuation correction in PET versus SPECT

    NASA Astrophysics Data System (ADS)

    Marshall, H. R.; Stodilka, R. Z.; Theberge, J.; Sabondjian, E.; Legros, A.; Deans, L.; Sykes, J. M.; Thompson, R. T.; Prato, F. S.

    2011-07-01

    Attenuation correction (AC) is a critical step in the reconstruction of quantitatively accurate positron emission tomography (PET) and single photon emission computed tomography (SPECT) images. Several groups have proposed magnetic resonance (MR)-based AC algorithms for application in hybrid PET/MR systems. However, none of these approaches have been tested on SPECT data. Since SPECT/MR systems are under active development, it is important to ascertain whether MR-based AC algorithms validated for PET can be applied to SPECT. To investigate this issue, two imaging experiments were performed: one with an anthropomorphic chest phantom and one with two groups of canines. Both groups of canines were imaged from neck to abdomen, one with PET/CT and MR (n = 4) and the other with SPECT/CT and MR (n = 4), while the phantom was imaged with all modalities. The quality of the nuclear medicine reconstructions using MR-based attenuation maps was compared between PET and SPECT on global and local scales. In addition, the sensitivity of these reconstructions to variations in the attenuation map was ascertained. On both scales, it was found that the SPECT reconstructions were of higher fidelity than the PET reconstructions. Further, they were less sensitive to changes to the MR-based attenuation map. Thus, MR-based AC algorithms that have been designed for PET/MR can be expected to demonstrate improved performance when used for SPECT/MR.

  12. SPECT/CT: an update on technological developments and clinical applications.

    PubMed

    Ljungberg, Michael; Pretorius, P Hendrik

    2017-01-16

    Functional nuclear medicine imaging with single-photon emission CT (SPECT) in combination with anatomical CT has been commercially available since the beginning of this century. The combination of the two modalities has improved both the sensitivity and specificity of many clinical applications and CT in conjunction with SPECT that allows for spatial overlay of the SPECT data on good anatomy images. Introduction of diagnostic CT units as part of the SPECT/CT system has also potentially allowed for a more cost-efficient use of the equipment. Most of the SPECT systems available are based on the well-known Anger camera principle with NaI(Tl) as a scintillation material, parallel-hole collimators and multiple photomultiplier tubes, which, from the centroid of the scintillation light, determine the position of an event. Recently, solid-state detectors using cadmium-zinc-telluride became available and clinical SPECT cameras employing multiple pinhole collimators have been developed and introduced in the market. However, even if new systems become available with better hardware, the SPECT reconstruction will still be affected by photon attenuation and scatter and collimator response. Compensation for these effects is needed even for qualitative studies to avoid artefacts leading to false positives. This review highlights the recent progress for both new SPECT cameras systems as well as for various data-processing and compensation methods.

  13. Distinction between hemangioma of the liver and hepatocellular carcinoma: value of labeled RBC-SPECT scanning

    SciTech Connect

    Kudo, M.; Ikekubo, K.; Yamamoto, K.; Ibuki, Y.; Hino, M.; Tomita, S.; Komori, H.; Orino, A.; Todo, A.

    1989-05-01

    The role of adding single-photon emission CT (SPECT) to /sup 99m/Tc-labeled RBC imaging of the liver was evaluated by specifically focusing on the differentiation between hepatic hemangioma and hepatocellular carcinoma. Planar RBC imaging followed by blood-pool SPECT scanning was performed in 77 patients with a total of 108 hemangiomas and in 29 patients with a total of 46 hepatocellular carcinomas. All lesions were smaller than 5 cm in diameter. Thirty-six (33%) of 108 hemangiomas were detected by planar delayed RBC imaging, whereas 63 (58%) were detected by the delayed RBC-SPECT scan. The smallest hemangioma shown by delayed RBC-SPECT scanning was 1.4 cm in diameter, compared with 1.7 cm by planar RBC scanning. When confined to nodules larger than 1.4 cm in diameter, 42% of hemangiomas (36/85) were detected by planar delayed RBC imaging, whereas 74% (63/85) were detected by delayed RBC-SPECT. Increase in sensitivity was noted in nodules 2.1-4.0 cm in diameter. No hepatocellular carcinomas were shown by delayed RBC planar or SPECT scans. We concluded that with the addition of SPECT, the sensitivity of delayed RBC scans in the detection of small hemangiomas is considerably improved. Delayed RBC-SPECT scanning can be used to distinguish hemangioma from hepatocellular carcinoma.

  14. SPECT-OPT multimodal imaging enables accurate evaluation of radiotracers for β-cell mass assessments

    PubMed Central

    Eter, Wael A.; Parween, Saba; Joosten, Lieke; Frielink, Cathelijne; Eriksson, Maria; Brom, Maarten; Ahlgren, Ulf; Gotthardt, Martin

    2016-01-01

    Single Photon Emission Computed Tomography (SPECT) has become a promising experimental approach to monitor changes in β-cell mass (BCM) during diabetes progression. SPECT imaging of pancreatic islets is most commonly cross-validated by stereological analysis of histological pancreatic sections after insulin staining. Typically, stereological methods do not accurately determine the total β-cell volume, which is inconvenient when correlating total pancreatic tracer uptake with BCM. Alternative methods are therefore warranted to cross-validate β-cell imaging using radiotracers. In this study, we introduce multimodal SPECT - optical projection tomography (OPT) imaging as an accurate approach to cross-validate radionuclide-based imaging of β-cells. Uptake of a promising radiotracer for β-cell imaging by SPECT, 111In-exendin-3, was measured by ex vivo-SPECT and cross evaluated by 3D quantitative OPT imaging as well as with histology within healthy and alloxan-treated Brown Norway rat pancreata. SPECT signal was in excellent linear correlation with OPT data as compared to histology. While histological determination of islet spatial distribution was challenging, SPECT and OPT revealed similar distribution patterns of 111In-exendin-3 and insulin positive β-cell volumes between different pancreatic lobes, both visually and quantitatively. We propose ex vivo SPECT-OPT multimodal imaging as a highly accurate strategy for validating the performance of β-cell radiotracers. PMID:27080529

  15. SPECT-OPT multimodal imaging enables accurate evaluation of radiotracers for β-cell mass assessments.

    PubMed

    Eter, Wael A; Parween, Saba; Joosten, Lieke; Frielink, Cathelijne; Eriksson, Maria; Brom, Maarten; Ahlgren, Ulf; Gotthardt, Martin

    2016-04-15

    Single Photon Emission Computed Tomography (SPECT) has become a promising experimental approach to monitor changes in β-cell mass (BCM) during diabetes progression. SPECT imaging of pancreatic islets is most commonly cross-validated by stereological analysis of histological pancreatic sections after insulin staining. Typically, stereological methods do not accurately determine the total β-cell volume, which is inconvenient when correlating total pancreatic tracer uptake with BCM. Alternative methods are therefore warranted to cross-validate β-cell imaging using radiotracers. In this study, we introduce multimodal SPECT - optical projection tomography (OPT) imaging as an accurate approach to cross-validate radionuclide-based imaging of β-cells. Uptake of a promising radiotracer for β-cell imaging by SPECT, (111)In-exendin-3, was measured by ex vivo-SPECT and cross evaluated by 3D quantitative OPT imaging as well as with histology within healthy and alloxan-treated Brown Norway rat pancreata. SPECT signal was in excellent linear correlation with OPT data as compared to histology. While histological determination of islet spatial distribution was challenging, SPECT and OPT revealed similar distribution patterns of (111)In-exendin-3 and insulin positive β-cell volumes between different pancreatic lobes, both visually and quantitatively. We propose ex vivo SPECT-OPT multimodal imaging as a highly accurate strategy for validating the performance of β-cell radiotracers.

  16. Single photon emission computed tomography (SPECT) and SPECT/low-dose computerized tomography did not increase sensitivity or specificity compared to planar bone scintigraphy for detection of bone metastases in advanced breast cancer.

    PubMed

    Haraldsen, Ate; Bluhme, Henrik; Røhl, Lisbeth; Pedersen, Erik Morre; Jensen, Anders Bonde; Hansen, Eva Boysen; Nellemann, Hanne; Rasmussen, Finn; Morsing, Anni

    2016-01-01

    To evaluate and compare the diagnostic performance of whole-body planar bone scintigraphy (WBS), single photon emission computed tomography (SPECT), SPECT/low-dose computerized tomography (SPECT/ldCT) and SPECT/contrast enhanced diagnostic CT (SPECT/cdCT) in the staging of patients with advanced breast cancer. Seventy-eight patients with recurrence of biopsy-proven breast cancer and suspicion of disseminated disease were investigated with WBS, SPECT, SPECT/ldCT, SPECT/cdCT and MRI performed on the same day in this prospective study. Images were separately analysed in a blinded fashion by radiologists and nuclear medicine physicians regarding the presence of pathological findings. MRI served as reference standard. According to reference standard, 38 of 73 patients had bone metastases. The sensitivity was 87%, 87%, 79%, and 84% and specificity 63%, 71%, 63% and 83% for WBS, SPECT, SPECT/ldCT and SPECT/cdCT. A significantly increased specificity of SPECT/cdCT compared to WBS and SPECT/ldCT was found, and other parameters did not differ significantly between modalities. Additional two patients had bone metastases solely located outside the MRI scan field and seven patients had soft tissue metastases, but no skeletal changes on MRI. WBS, SPECT and SPECT/ldCT were less sensitive than MRI and equally specific for the detection of bone metastases in patients with advanced breast cancer. Based on our findings, we suggest that initial staging include WBS, MRI of the spine and CT for soft tissue evaluation. Further studies may clarify the potential benefits of whole-body MRI and 18F-NaF PET/CT or 18F-FDG PET/CT. © 2014 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  17. Synthesis and Structure-Affinity Relationships of Selective High-Affinity 5-HT4 Receptor Antagonists: Application to the Design of New Potential Single Photon Emission Computed Tomography (SPECT) Tracers

    PubMed Central

    Dubost, Emmanuelle; Dumas, Noé; Fossey, Christine; Magnelli, Rosa; Butt-Gueulle, Sabrina; Ballandonne, Céline; Caignard, Daniel H.; Dulin, Fabienne; de-Oliveira Santos, Jana Sopkova; Millet, Philippe; Charnay, Yves; Rault, Sylvain; Cailly, Thomas; Fabis, Frederic

    2012-01-01

    The work described herein aims at finding new potential ligands for the brain imaging of 5-HT4 receptors using single-photon emission computed tomography (SPECT). Starting from the non-substituted phenanthridine compound 4a exhibiting a Ki value of 51 nM on 5-HT4R, we explored structure-affinity in this series. We found that substitution in position 4 of the tricycle with a fluorine atom gave the best result. Introduction of an additional nitrogen atom inside the tricyclic framework led to increase both the affinity and the selectivity for 5-HT4R suggesting the design of the antagonist 4v exhibiting a high affinity of 0.04 nM. Several iodinated analogues were then synthesized as potential SPECT tracers. The iodinated compound 11d was able to displace the reference radioiodinated 5-HT4R antagonist (1-butylpiperidin-4-yl)methyl-8-amino-7-iodo[123I]-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxylate ([123I]1, [123I]SB 207710) both in vitro and in vivo in brain. Compound 11d was radiolabeled with [125I]iodine, providing a potential SPECT candidate for brain imaging of 5-HT4R. PMID:23102207

  18. Evaluation of quantitative accuracy in CZT-based pre-clinical SPECT for various isotopes

    NASA Astrophysics Data System (ADS)

    Park, S.-J.; Yu, A. R.; Kim, Y.-s.; Kang, W.-S.; Jin, S. S.; Kim, J.-S.; Son, T. J.; Kim, H.-J.

    2015-05-01

    In vivo pre-clinical single-photon emission computed tomography (SPECT) is a valuable tool for functional small animal imaging, but several physical factors, such as scatter radiation, limit the quantitative accuracy of conventional scintillation crystal-based SPECT. Semiconductor detectors such as CZT overcome these deficiencies through superior energy resolution. To our knowledge, little scientific information exists regarding the accuracy of quantitative analysis in CZT-based pre-clinical SPECT systems for different isotopes. The aim of this study was to assess the quantitative accuracy of CZT-based pre-clinical SPECT for four isotopes: 201Tl, 99mTc, 123I, and 111In. The quantitative accuracy of the CZT-based Triumph X-SPECT (Gamma-Medica Ideas, Northridge, CA, U.S.A.) was compared with that of a conventional SPECT using GATE simulation. Quantitative errors due to the attenuation and scatter effects were evaluated for all four isotopes with energy windows of 5%, 10%, and 20%. A spherical source containing the isotope was placed at the center of the air-or-water-filled mouse-sized cylinder phantom. The CZT-based pre-clinical SPECT was more accurate than the conventional SPECT. For example, in the conventional SPECT with an energy window of 10%, scatter effects degraded quantitative accuracy by up to 11.52%, 5.10%, 2.88%, and 1.84% for 201Tl, 99mTc, 123I, and 111In, respectively. However, with the CZT-based pre-clinical SPECT, the degradations were only 9.67%, 5.45%, 2.36%, and 1.24% for 201Tl, 99mTc, 123I, and 111In, respectively. As the energy window was increased, the quantitative errors increased in both SPECT systems. Additionally, the isotopes with lower energy of photon emissions had greater quantitative error. Our results demonstrated that the CZT-based pre-clinical SPECT had lower overall quantitative errors due to reduced scatter and high detection efficiency. Furthermore, the results of this systematic assessment quantifying the accuracy of these SPECT

  19. Automatic estimation of detector radial position for contoured SPECT acquisition using CT images on a SPECT/CT system

    SciTech Connect

    Liu Ruijie Rachel; Erwin, William D.

    2006-08-15

    An algorithm was developed to estimate noncircular orbit (NCO) single-photon emission computed tomography (SPECT) detector radius on a SPECT/CT imaging system using the CT images, for incorporation into collimator resolution modeling for iterative SPECT reconstruction. Simulated male abdominal (arms up), male head and neck (arms down) and female chest (arms down) anthropomorphic phantom, and ten patient, medium-energy SPECT/CT scans were acquired on a hybrid imaging system. The algorithm simulated inward SPECT detector radial motion and object contour detection at each projection angle, employing the calculated average CT image and a fixed Hounsfield unit (HU) threshold. Calculated radii were compared to the observed true radii, and optimal CT threshold values, corresponding to patient bed and clothing surfaces, were found to be between -970 and -950 HU. The algorithm was constrained by the 45 cm CT field-of-view (FOV), which limited the detected radii to {<=}22.5 cm and led to occasional radius underestimation in the case of object truncation by CT. Two methods incorporating the algorithm were implemented: physical model (PM) and best fit (BF). The PM method computed an offset that produced maximum overlap of calculated and true radii for the phantom scans, and applied that offset as a calculated-to-true radius transformation. For the BF method, the calculated-to-true radius transformation was based upon a linear regression between calculated and true radii. For the PM method, a fixed offset of +2.75 cm provided maximum calculated-to-true radius overlap for the phantom study, which accounted for the camera system's object contour detect sensor surface-to-detector face distance. For the BF method, a linear regression of true versus calculated radius from a reference patient scan was used as a calculated-to-true radius transform. Both methods were applied to ten patient scans. For -970 and -950 HU thresholds, the combined overall average root-mean-square (rms) error

  20. Erythropoietin Pretreatment of Transplanted Endothelial Colony-Forming Cells Enhances Recovery in a Cerebral Ischemia Model by Increasing Their Homing Ability: A SPECT/CT Study.

    PubMed

    Garrigue, Philippe; Hache, Guillaume; Bennis, Youssef; Brige, Pauline; Stalin, Jimmy; Pellegrini, Lionel; Velly, Lionel; Orlandi, Francesca; Castaldi, Elena; Dignat-George, Françoise; Sabatier, Florence; Guillet, Benjamin

    2016-11-01

    Endothelial colony-forming cells (ECFCs) are promising candidates for cell therapy of ischemic diseases, as less than 10% of patients with an ischemic stroke are eligible for thrombolysis. We previously reported that erythropoietin priming of ECFCs increased their in vitro and in vivo angiogenic properties in mice with hindlimb ischemia. The present study used SPECT/CT to evaluate whether priming of ECFCs with erythropoietin could enhance their homing to the ischemic site after transient middle cerebral artery occlusion (MCAO) followed by reperfusion in rats and potentiate their protective or regenerative effect on blood-brain barrier (BBB) disruption, cerebral apoptosis, and cerebral blood flow (CBF).

  1. Tc-99m SPECT sestamibi for the measurement of infarct size.

    PubMed

    Gibbons, Raymond J

    2011-01-01

    There are a variety of approaches to assess the efficacy of reperfusion therapy, and myocardial protection, in acute myocardial infarction. This review summarizes the available evidence validating the use of technetium-99m sestamibi single-photon emission computed tomography (SPECT) for this purpose. Multiple lines of evidence have validated its clinical utility. SPECT sestamibi infarct size has been used as an endpoint in multiple randomized clinical trials. A smaller number of clinical trials have used both early and later imaging with SPECT sestamibi to assess myocardium at risk and myocardial salvage. SPECT sestamibi has a number of limitations which must be recognized. Nevertheless, SPECT sestamibi infarct size is a well-validated measurement with a long track record of performance as an endpoint in multicenter, randomized clinical trials.

  2. Experimental studies of SPECT scintimammography with combined cone-beam and parallel-beam collimators

    NASA Astrophysics Data System (ADS)

    Krol, Andrzej; Feiglin, David H.; Gangal, K. R.; Coman, Ioana L.; Salgado, Roberto B.; Lipson, Edward D.; Karczewski, Deborah A.; Thomas, Frank D.

    2003-05-01

    Conventional SPECT Tc-99m sestamibi scintimammography (STSM) has limited clinical utility due to fairly low radiopharmaceutical uptake in the breast tissue as compared to the heart and the liver. We investigated the use of a cone-beam collimator (CBC) to STSM. Each detector on a multi-headed gamma camera can be equipped with parallel-beam (PBC) or cone-beam collimators (CBC). PBC can provide truncation-free SPECT projection sets, while CBC offers increased sensitivity in a limited field-of-view (FOV). Combined PBC and CBC SPECT ddata acquisition may provide improved lesion contrast and overall better imaging performance within CBC FOV with significantly reduced truncation artifacts in the reconstructed images. In this paper we evaluate the combined CBC&PBC SPECT method using a limited number of confirmed breast cancer patients and female chest phantoms with simulated breast lesions. We envision the combined CBC&PBC SPECT as a useful clinical tool in scintimammography.

  3. A Vector Uniform Cramer-Rao Bound for SPECT System Design

    PubMed Central

    Meng, Ling-Jian; Li, Nan

    2016-01-01

    In this paper, we present the use of modified uniform Cramer-Rao type bounds (MUCRB) for the design of single photon emission tomography (SPECT) systems. The MUCRB is the lowest attainable total variance using any estimator of an unknown vector parameter, whose mean gradient matrix satisfies a given constraint. Since the mean gradient is closely related to local impulse function, the MUCRB approach can be used to evaluate the fundamental tradeoffs between spatial resolution and variance that are achievable with a given SPECT system design. As a possible application, this approach allows one to compare different SPECT system designs based on the optimum average resolution-variance tradeoffs that can be achieved across multiple control-points inside a region-of-interest. The formulation of the MUCRB allows detailed modelling of physical aspects of practical SPECT systems and requests only a modest computation load. It can be used as an analytical performance index for comparing different SPECT system or aperture designs.

  4. Simulation study on a stationary data acquisition SPECT system with multi-pinhole collimators attached to a triple-head gamma camera system.

    PubMed

    Ogawa, Koichi; Ichimura, Yuta

    2014-10-01

    The aim of the study was to develop a new SPECT system that makes it possible to acquire projection data stationary using a triple-head gamma camera system. We evaluated several data acquisition geometry with multi-pinhole collimators attached to a triple-head gamma camera system. The number of pinholes for each camera was three to twelve, and we located these holes on collimator plates adequately. These collimator holes were tilted by predefined angles to efficiently cover the field of view of the data acquisition system. Acquired data were reconstructed with the OS-EM method. In the simulations, we used a three-dimensional point source phantom, brain phantom, and myocardial phantom. Attenuation correction was conducted with the x-ray CT image of the corresponding slice. Reconstructed images of the point source phantom showed that the spatial resolution could be improved with the small number of pinholes. On the other hand, reconstructed images of the brain phantom showed that the large number of pinholes yielded images with less artifact. The results of the simulations with the myocardial phantom showed that more than eight pinholes could yield an accurate distribution of activity when the source was distributed only in the myocardium. The results of the simulations confirmed that more than eight pinholes for each detector were required to reconstruct an artifact free image in the triple-head SPECT system for imaging of brain and myocardium.

  5. Comparative evaluation of MRS and SPECT in prognostication of patients with mild to moderate head injury.

    PubMed

    Dhandapani, Sivashanmugam; Sharma, Anurag; Sharma, Karamchand; Das, Lakshman

    2014-05-01

    Magnetic resonance spectroscopy (MRS) and single-photon emission computed tomography (SPECT) have only been individually studied in patients with head injury. This study aimed to comparatively assess both in patients with mild to moderate head injury. Patients with a Glasgow Coma Scale (GCS) score of 9-14 who underwent MRS and/or SPECT were evaluated in relation to various clinical factors and neurological outcome at 3months. There were 56 SPECT (Tc99m-ethylcysteinate dimer [ECD]) studies and 41 single voxel proton MRS performed in 53 patients, with 41 patients having both. Of the 41 who underwent MRS, 13 had a lower N-acetyl-aspartate/creatine (NAA/Cr) ratio, 14 had a higher choline (Cho)/Cr ratio, 19 were normal, and nine had bilateral MRS abnormalities. Of the 56 who underwent SPECT, 22 and 19 had severe and moderate hypop