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Nuclear Science, IEEE Transactions on

Issue 6  Part 2 • Date Dec. 1998

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Displaying Results 1 - 24 of 24
  • Author index

    Publication Year: 1998 , Page(s): 3149
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    Freely Available from IEEE
  • Attenuation correction in PET using consistency information

    Publication Year: 1998 , Page(s): 3134 - 3141
    Cited by:  Papers (27)
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    In this study the authors use the consistency conditions of the Radon transform to aid attenuation correction in PET. The conditions are used both for estimating the parameters of a uniform elliptical attenuation distribution (without any transmission measurements) and for correcting for patient motion between the transmission and emission acquisitions. The results show that, for a uniform elliptical attenuation distribution, the reconstructed count densities obtained using attenuation correction based on the consistency conditions are within 1% of the true values. The method is shown to be fairly tolerant to the effects of photon counting statistics and to small non-uniformities in the attenuation distribution (such as skull attenuation). The results also show that the consistency conditions may be useful in correcting for patient motion. The method is shown to effectively compensate for shifts in two dimensions using both simulated and experimental data View full abstract»

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  • Pulmonary organs analysis for differential diagnosis based on thoracic thin-section CT images

    Publication Year: 1998 , Page(s): 3075 - 3082
    Cited by:  Papers (18)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1372 KB)  

    The pulmonary organs have a very complicated structure which consists of the bronchus, the pulmonary artery, and the pulmonary vein. So it is difficult for a medical doctor to understand the spatial relationships among a tumor and the pulmonary organs. Here, the authors present a 3D image analysis method of the pulmonary organs based on thin-section CT images. First, they extract the regions of interest using Gaussian curvature and mean curvature of lung field, then they classify the bronchus and the blood vessels, and they conclude with the identification of the pulmonary artery and the pulmonary vein. The authors use this method to support a differential diagnosis of lung cancer by making quantitative analysis of abnormal nodules View full abstract»

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  • Kalman sinogram restoration for fast and accurate PET image reconstruction

    Publication Year: 1998 , Page(s): 3022 - 3029
    Cited by:  Papers (5)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (876 KB)  

    Sinogram restoration followed by filtered backprojection (FBP) is a fast method for obtaining PET images of good quality and quantitative accuracy. In previous studies, the authors used detector motion and the method of projection onto convex sets for sinogram restoration to improve on FBP reconstruction; but, the performance was observed to degrade rapidly when the noise level of PET data increased. In this paper, the authors describe a sinogram restoration method based on Kalman filtering that provides promising results in computer simulations. The potential benefits of this new method includes improved noise performance and a low computational cost which is comparable to that of conventional FBP View full abstract»

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  • Coherent scatter implementation for SimSET

    Publication Year: 1998 , Page(s): 3064 - 3068
    Cited by:  Papers (15)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (448 KB)  

    At 140 keV, 3% of photon scatter interactions in human tissues are coherent scatter; at Tl-201 emission energies, this fraction increases to approximately 7%. However, since coherent scatter at these energies is sharply forward-peaked, it is often the dominant scatter interaction at small angles. SimSET (Simulation System for Emission Tomography), which previously modeled only photoelectric absorption and Compton scatter, has been extended to include coherent scatter. The current implementation uses form factor and anomalous scattering amplitude data from the Livermore Evaluated Photon Data Library. Interaction probability and angular distribution tables for several human tissues and common detector materials were calculated using the independent atoms approximation and human-tissue composition data from the ICRP Reference Man. These data were also used to generate new tables for photoelectric absorption and Compton scatter, significantly improving the accuracy of SimSET and extending its photon tracking capability to lower photon energy (from 50 keV to 1 keV). The form, content, and structure of the tables were carefully designed for efficient data storage, access, and use by the software. The derived data tables and implementation of coherent scatter were validated by comparing simulation results to published differential cross-section data View full abstract»

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  • First results with high-resolution PET detector modules using wavelength-shifting fibers

    Publication Year: 1998 , Page(s): 2993 - 2999
    Cited by:  Papers (7)
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    The authors have constructed and tested prototype PET detector modules incorporating wavelength-shifting fiber ribbons alternating with thin CsI(Na) scintillator plates in multilayer stacks. Modules with cross-sectional area of 11 cm×11 cm and with 9 mm of total crystal thickness have been tested. A reconstructed spatial resolution of 3 mm FWHM has been obtained for a line source, with an energy resolution of <20% and a time resolution of 25 ns FWHM. Energy measurements and coincidence timing are provided by 4 photomultipliers in an Auger array on one 11 cm×11 cm module face. Multiplexed fiber readout has been implemented with multianode photomultipliers coupled to several fiber ribbons. The methods and resolution achieved are readily extended to larger systems in a straightforward and cost-effective manner. Results of tests with several phantoms are presented View full abstract»

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  • A coronary calcification diagnosis system based on helical CT images

    Publication Year: 1998 , Page(s): 3083 - 3088
    Cited by:  Papers (1)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1284 KB)  

    Describes a computer assisted diagnostic algorithm for coronary calcifications based on helical X-ray CT images which is used in mass screening process for lung cancer diagnosis. The authors' diagnostic algorithm consists of four processes: First, they choose the heart slices from the CT images which were taken at the mass screening. They classify the heart slices into three sections which have different coronary geometries, using the information of the heart shape, trachea, CT values in the heart region, and the bone. Second, the authors extract the heart region in each slice, using the information of the lung shape and the body of vertebra. Third, they detect the candidate regions of the coronary calcifications using an edge filter and thresholding pixel values. Finally, to increase the effectiveness of the diagnosis, the authors exclude the artifact regions included in the candidate regions by using the diagnostic rule based on a neural network. They applied this algorithm to helical CT images of 462 patients screened for lung cancer. The results generated by this system were compared with a physician's diagnosis. This system could detect 213 of 214 regions which were diagnosed as coronary calcifications or probably coronary calcifications by a physician. There was only one false negative case. The false positive ratio was 0.30 per patient View full abstract»

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  • Limited sinogram completion for transmission SPECT imaging

    Publication Year: 1998 , Page(s): 3036 - 3044
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    Truncation artifacts can occur in simultaneous emission transmission SPECT imaging even with parallel geometry, especially when the acquistion geometry is optimized for emission at the expense of the transmission data. The authors hypothesized that the addition of only a few projections sampling truncated areas (by shifting the bed/camera) would permit a significant improvement in image quality with only a small increase in imaging time. In parallel geometry, data are preprocessed and the additional projections are merged into the original sinogram, thereby partially completing it. For fan-beam data, the projector routine is modified to take into account different bed positions. Both cases require the use of an iterative reconstruction algorithm. Improvements due to partial completion are shown for different increases of total imaging time for both geometries. On simulated and true data, a 15% increase of imaging time led to a better recovery of the truncated area than obtained from a priori knowledge of the body contour View full abstract»

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  • Kinetic parameter estimation from attenuated SPECT projection measurements

    Publication Year: 1998 , Page(s): 3007 - 3013
    Cited by:  Papers (27)  |  Patents (35)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (952 KB)  

    Conventional analysis of dynamically acquired nuclear medicine data involves fitting kinetic models to time-activity curves generated from regions of interest defined on a temporal sequence of reconstructed images. However, images reconstructed from the inconsistent projections of a time-varying distribution of radiopharmaceutical acquired by a rotating SPECT system can contain artifacts that lead to biases in the estimated kinetic parameters. To overcome this problem the authors investigated the estimation of kinetic parameters directly from projection data by modeling the data acquisition process. To accomplish this it was necessary to parametrize the spatial and temporal distribution of the radiopharmaceutical within the SPECT field of view. In a simulated transverse slice, kinetic parameters were estimated for simple one compartment three myocardial regions of interest, as well as for the liver. Myocardial uptake and washout parameters estimated by conventional analysis of noiseless simulated data had biases ranging between 1-63%. Parameters estimated directly from the noiseless projection data were unbiased as expected, since the model used for fitting was faithful to the simulation. Predicted uncertainties (standard deviations) of the parameters obtained for 500,000 detected events ranged between 2-31% for the myocardial uptake parameters and 2-23% for the myocardial washout parameters View full abstract»

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  • High resolution X-ray imaging using a silicon strip detector

    Publication Year: 1998 , Page(s): 3059 - 3063
    Cited by:  Papers (20)  |  Patents (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (448 KB)  

    The authors present the first images and an initial evaluation of a scanned-slot X-ray imaging system based on edge-on silicon strip detectors and high-speed low-noise parallel processing ASICs. The authors have demonstrated noiseless single photon counting above a minimal threshold of 7.2 keV. Edge scans show negligible cross talk between different channels in the ASIC. The Modulation Transfer Function (MTF) has been measured and found to agree with the ideal MTF for 100 μm pixel size. The first images are obtained at very low exposures and show the high performance of the system. The authors also present a way of enhancing the X-ray flux to a slot by using a refractive X-ray lens. They believe this focusing device will significantly enhance the potential for scanned-slot X-ray imaging View full abstract»

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  • Using local median as the location of the prior distribution in iterative emission tomography image reconstruction

    Publication Year: 1998 , Page(s): 3097 - 3104
    Cited by:  Papers (27)
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    Iterative reconstruction algorithms like MLEM (Maximum Likelihood Expectation Maximization) can be regularized using a weighted roughness penalty term according to certain a priori assumptions of the desired image. In the R?RP (Median Root Prior) algorithm the penalty is set according to the deviance of a pixel from the local median. This allows both noise reduction and edge preservation. The prior distribution is Gaussian located around the median of a neighborhood of the pixel. Non-monotonic details smaller than a given limit are considered as noise and are penalized. Thus, MRP implicitly contains the general description of the characteristics of the desired emission image, and good localization of tissue boundaries is achieved without anatomical data. In contrast to the MLEM method, the number of iterations needs not be restricted and unlike many other Bayesian methods MRP has only one parameter. The penalty term can be applied to various iterative reconstruction algorithms. The assumption that the true pixel value is close to the local median applies to any emission images, including the 3D acquisition and images reconstructed from parametric sinograms View full abstract»

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  • Design features and performance of a CsI(Na) array based gamma camera for small animal gene research

    Publication Year: 1998 , Page(s): 3053 - 3058
    Cited by:  Papers (17)
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    The authors report on the development and performance of a radiation imaging system based on a 110 mm diameter matrix of 1 mm×1 mm size CsI(Na) scintillating crystals. This detector system has been optimized for high resolution radiation imaging of the distribution of iodine 125 (125I) in a laboratory animal. The radioisotope 125I is readily available as a label to molecular biology probes that can be used in gene research. The system utilizes the Hamamatsu 5 inch diameter 3292 position sensitive photomultiplier tube (PSPMT) coupled to the CsI(Na) matrix and a custom built high resolution copper-beryllium collimator. A resulting spatial resolution of the order of 1.5 mm FWHM and a sensitivity of 68 cpm/μCi were obtained with the copper-beryllium collimator. The detector system is installed on a rotating gantry to obtain multiple projections and is now being used in animal studies View full abstract»

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  • Attenuation effects in gamma-camera coincidence imaging

    Publication Year: 1998 , Page(s): 3115 - 3121
    Cited by:  Papers (3)
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    Images produced by gamma camera coincidence (GCC) techniques have a much lower count-density than those produced by dedicated PET scanners. The authors examine the effects of attenuation and attenuation correction on GCC images using gamma-camera emission data and PET emission and transmission data from phantom and human studies. The effects studied include contrast, noise, and general image quality. Results show that lung lesion contrast is improved but the signal-to-noise ratio is slightly degraded by the application of attenuation correction. Additionally, the corrected images do not contain the distortions of the uncorrected images and they more accurately show the activity distribution of the imaged object. The noise studies suggest that statistically appropriate transmission data for implementing an attenuation correction can be acquired in a small fraction of the time used for an emission scan View full abstract»

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  • Segmented LSO crystals for depth-of-interaction encoding in PET

    Publication Year: 1998 , Page(s): 3030 - 3035
    Cited by:  Papers (22)  |  Patents (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (504 KB)  

    The authors have developed a method of effecting depth-of-interaction sensitivity for PET detectors. It exploits a significant difference in the index of refraction between adjacent scintillator segments and the compound optically coupling them, to induce discrete and resolved photopeak pulse heights depending on the segment of interaction of γ-rays. The approach was put to a first experimental test by manufacturing two prototypes with LSO crystals of dimensions 4×4×30 mm and 2.5×2.5×20 mm respectively, each comprising three segments along their longitudinal axis. Measurements of their absolute pulse height responses when irradiated by 511 keV photons are presented and show resolved peaks for photoelectric interactions occurring in each longitudinal segment as desired. For the second of the above prototypes, the lowest(highest) of these peaks is measured to correspond to a pulse height of 335(559) photoelectrons with full-width-at-half-maximum resolution of 28%(12%). The expected performances of PET detector units comprising a plurality of such segmented crystals is also discussed View full abstract»

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  • Properties of minimum cross-entropy reconstruction of emission tomography with anatomically based prior

    Publication Year: 1998 , Page(s): 3014 - 3021
    Cited by:  Papers (8)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (960 KB)  

    The authors have studied the properties of a minimum cross-entropy (MXE) algorithm for emission tomography reconstruction with anatomical prior images. MXE is implemented with two terms: a maximum likelihood expectation maximization term and a penalty term for regularization within anatomically defined boundaries. The relative emphasis put on the two competing terms is controlled by the regularization constant β. Edge resolution and noise level were compared for reconstructions with and without corresponding prior image. The prior lends to significant edge enhancement with edge resolution converging to a lower limit independent of β. Normalized standard deviation (NSD) and resolution both illustrate that regularization within boundaries behaves predictably with more smoothing for larger β. Application of ordered subsets (OS) was also investigated. For OS, edge enhancement is fully preserved but NSD increases for low subset size. Results demonstrate that OS is applicable to MXE provided subset size is greater than 4. OS-MXE has appealing properties for regularized reconstruction View full abstract»

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  • Performance results of a new DOI detector block for a high resolution PET-LSO research tomograph HRRT

    Publication Year: 1998 , Page(s): 3000 - 3006
    Cited by:  Papers (55)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (684 KB)  

    To improve the spatial resolution and uniformity in modern high resolution brain PET systems over the entire field of view (FOV), it is necessary to archive the depth of interaction (DOI) information and correct for spatial resolution degradation. In this work we present the performance results of a high resolution LSO/GSO phoswich block detector with DOI capability. This detector design will be used in the new CTI High Resolution Research Tomograph, ECAT HRRT. The two crystal layers (19×19×7.5 mm3) and a light guide are stacked on each other and mounted on a (2×2) PMT set, so that the corners of the phoswich are positioned over the PMT centers. The crystal phoswich is cut into an 8×8 matrix of discrete crystals. The separation of the LSO and the GSO layer by pulse shape discrimination allows discrete DOI information to be obtained. The high light output and the light guide design results in an accurate identification of the 128 single crystals per block. Flood source measurements document a very good homogeneity of events, energy centroid stability and energy resolution (14-20% FWHM) per single crystal. An intrinsic resolution of ~1.3 mm and the DOI feasibility is extracted by coincidence measurements with a single GSO crystal View full abstract»

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  • Computer-aided diagnostic system for diffuse liver diseases with ultrasonography by neural networks

    Publication Year: 1998 , Page(s): 3069 - 3074
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (740 KB)  

    The aim of the study is to establish a computer-aided diagnostic system for diffuse liver diseases such as chronic active hepatitis (CAH) and liver cirrhosis (LC). The authors introduced an artificial neural network in the classification of these diseases. In this system the neural network was trained by feature parameters extracted from B-mode ultrasonic images of normal liver (NL), CAH and LC. For input data the authors used six parameters calculated by a region of interest (ROI) and a parameter calculated by five ROIs in each image. They were variance of pixel values, coefficient of variation, annular Fourier power spectrum, longitudinal Fourier power spectrum which were calculated for the ROI, and variation of the means of the five ROIs. In addition, the authors used two more parameters calculated from a co-occurrence matrix of pixel values in the ROI. The results showed that the neural network classifier was 83.8% in sensitivity for LC, 90.0% in sensitivity for CAH and 93.6% in specificity, and the system was considered to be helpful for clinical and educational use View full abstract»

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  • Effects of non-optimal acquisition geometry in myocardial perfusion imaging using Ectomography

    Publication Year: 1998 , Page(s): 3142 - 3148
    Cited by:  Papers (2)
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    Ectomography is a limited view angle method, which has been implemented by rotating a slant hole collimator in front of a stationary gamma camera detector. The system is mobile and can be used for acute perfusion studies. To achieve high image quality in myocardial perfusion imaging, the detector should be positioned perpendicular to the long axis of the left ventricle. The aim of this study is to investigate the effects of (1) misalignment of the detector head with respect to the left ventricle, (2) truncation of the myocardial projection images and (3) external activity. Phantom studies were performed with 5 different slant hole collimators. A heart phantom, containing two defects, was placed in a water filled thorax phantom. Studies with different degrees of misalignment were performed using a mobile tomographic gamma camera. Results show that up to 20° misalignment causes little influence on size, severity and position of the defect in the reconstructed sections, neither does presence of external activity. Effects of apical truncation do not propagate into non-truncated regions. In conclusion, positioning of a mobile system based on Ectomography does not have to be perfect, allowing rapid positioning in acute situations View full abstract»

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  • Dedicated gamma camera for single photon emission mammography (SPEM)

    Publication Year: 1998 , Page(s): 3127 - 3133
    Cited by:  Papers (12)
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    Prone scintimammography with Tc-99m SestaMIBI has been proposed as a method of detecting breast cancers in women with dense breasts. Clinical reports have shown that this technique lacks sensitivity for cancer smaller than 1 cm. To overcome some limitations offered by Auger camera on breast imaging was realized a new scintigraphic detector dedicated to SPEM (Single Photon Emission Mammography). This novel small FOV device, shows high spatial resolution performances (<2 mm), but poorer energy resolution values, than Auger camera (17% vs. 10%, respectively). In this paper the authors examine the spatial distribution of Compton-to-photopeak ratio in planar scintimammographic images in order to elucidate the causes of lack of scintimammography in visualizing deep or posteriorly located cancers introduced by the scatter from the patient's body. Phantom and clinical studies with several instruments including a general purpose gamma camera, a dedicated camera and a non-imaging Germanium detector were performed. The results obtained suggest that scatter from extramammary sources plays an important role in breast imaging with radiotracers. By using gentle breast compression in cranio-caudal view the energy resolution attained with the dedicated camera is adequate to differentiate between photopeak and Compton counts; the Compton-to photopeak mean ratio resulted 4.5 and 6.9 for mid portion and posterior breast respectively View full abstract»

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  • YAP-PET: first results of a small animal positron emission tomograph based on YAP:Ce finger crystals

    Publication Year: 1998 , Page(s): 3105 - 3108
    Cited by:  Papers (40)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (668 KB)  

    The authors have built a small animal Positron Emission Tomograph (YAP-PET) based on four matrices of 400 YAP:Ce finger crystals (2×2×30 mm3 each) coupled to a Position Sensitive PhotoMultiplier Hamamatsu R2486-06. The system consists of four detectors on a rotating gantry with a variable diameter from 10 and 25 cm. The read-out and data acquisition system are handled by NIM-CAMAC standard electronics. The tomograph has a total Field Of View (FOV) of 4×4×4 cm3 that is appropriate for mice and rat studies. A spatial resolution ⩽2 mm over 3×3×3 cm3 FOV has been measured, with a peak sensitivity for a point source of about 614 cps/μCi for a gantry diameter of 15 cm and an energy threshold of 50 keV View full abstract»

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  • Bayesian SPECT lung imaging for visualization and quantification of pulmonary perfusion

    Publication Year: 1998 , Page(s): 3045 - 3052
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    In this paper, the authors quantitatively and qualitatively examine the use of a Gibbs prior in maximum a posteriori (MAP) reconstruction of SPECT images of pulmonary perfusion using the expectation-maximization (EM) algorithm. This Bayesian approach is applied to SPECT projection data acquired from a realistic torso phantom with spherical defects in the lungs simulating perfusion deficits. Both the scatter subtraction constant (k) and the smoothing parameter beta (β) characterizing the prior are varied to study their effect on image quality and quantification. Region of interest (ROI) analysis is used to compare MAP-EM radionuclide concentration estimates with those derived from a “clinical” implementation of filtered backprojection (CFBP), and a quantitative implementation of FBP (QFBP) utilizing nonuniform attenuation and scatter compensation. Qualitatively, the MAP-EM images contain reduced artifacts near the lung boundaries relative to the FBP implementations. Generally, the MAP-EM image's visual quality and the ability to discern the areas of reduced radionuclide concentration in the lungs depend on the value of β and the total number of iterations. For certain choices of β and total iterations, MAP-EM lung images are visually comparable to FBP. Based on profile and ROI analysis, SPECT QFBP and MAP-EM images have the potential to provide quantitatively accurate reconstructions when compared to CFBP. The computational burden, however, is greater for the MAP-EM approach. To demonstrate the clinical efficacy of the methods, the authors present pulmonary images of a patient with lung cancer View full abstract»

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  • Quantitative 131I SPECT with triple energy window Compton scatter correction

    Publication Year: 1998 , Page(s): 3109 - 3114
    Cited by:  Papers (10)
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    In this work accuracy of quantitative 131I SPECT with triple energy window (TEW) scatter correction is evaluated by phantom measurements. The application is tumor imaging of B-cell lymphoma patients treated with 131I radioimmunotherapy. The TEW method is a pixel by pixel correction where the scatter fraction in the photopeak window is estimated by linear interpolation between two adjacent narrow sub-windows. For the phantom measurements performed in this work the TEW estimate of scattered counts was close to one half of the total photopeak window counts. Quantification procedure includes marker based X-ray CT-SPECT image fusion to determine object boundaries and to generate attenuation maps. TEW scatter correction significantly reduces the effect of background activity on reconstructed counts within an object, but it still exists due to the finite spatial resolution of the system. Therefore, a background dependent calibration factor had to be used to achieve good quantitative accuracy. Quantitative accuracy with TEW correction was 5% and 14% for a tumor and lung respectively of a physical phantom with non-uniform activity and non-uniform scattering medium. With no scatter subtraction but using a background dependent calibration the quantitative accuracy was 7% and 18% for the tumor and lung respectively View full abstract»

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  • Ultra high resolution pinhole SPECT for small animal study

    Publication Year: 1998 , Page(s): 3122 - 3126
    Cited by:  Papers (32)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (688 KB)  

    The aim of the study is to develop an ultra high-resolution pinhole SPECT system and analyze the performance by simulations. The pinhole SPECT was conducted with a Toshiba GCA-7200 A gamma camera. The diameter of the pinhole was 1 mm. Data were acquired with a 128×128 matrix, and the distance from the center of rotation (COR) to the pinhole was 20 mm [case 1] or 28 mm [case 2]. The data were collected at 4 degree increments over 360 degrees. The Feldkamp method was used for image reconstruction. Before the image reconstruction, the authors corrected the COR of the pinhole collimator. The imaging voxel was 0.27×0.27×0.27 mm3 [case 1] or 0.4×0.4×0.4 mm3 [case 2]. From the experiments with a resolution phantom the spatial resolution (FWHM) was 1.1 mm [case 1] or 1.3 mm [case 2]. The pinhole SPECT was also examined for in vivo imaging for studies of the heart in mice which were injected with Tc-99m-Tetrofosmin intravenously. In the reconstructed image the heart muscle of the mouse was clearly visualized. The authors also investigated the spatial resolution of the reconstructed image by means of simulations View full abstract»

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  • A Bayesian approach for edge detection in medical ultrasound images

    Publication Year: 1998 , Page(s): 3089 - 3096
    Cited by:  Papers (1)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (856 KB)  

    Successful applications of digital image processing techniques to medical ultrasound images have been limited in part because of the lack of an useful imaging model for clinical ultrasound B-scans. In this work, the authors derive a discrete linear imaging model appropriate for clinical ultrasound B-scans. Based on the newly derived model, the authors developed a Bayesian restoration approach that is currently designed for the generation of correct edges of medical ultrasound images. Their results demonstrate that successful edge detection can indeed be achieved by the proposed method. The proposed Bayesian approach is very flexible and has the potential of being extended to perform speckle reduction, edge detection, and region segmentation at the same time View full abstract»

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