Simultaneous Transmission

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James R. Corbett - One of the best experts on this subject based on the ideXlab platform.

  • Simultaneous Transmission/Emission Myocardial Perfusion Tomography Diagnostic Accuracy of Attenuation-Corrected 99mTc-Sestamibi Single-Photon Emission Computed Tomography
    Circulation, 1996
    Co-Authors: Edward P. Ficaro, Jeffrey A. Fessler, Paul D. Shreve, J.n. Kritzman, Patricia A. Rose, James R. Corbett
    Abstract:

    Background The purpose of the present study was to assess the diagnostic performance of attenuation-corrected (AC) stress 99mTc-sestamibi cardiac single-photon emission computed tomography (SPECT) for the identification of coronary heart disease (CHD). Methods and Results With a triple-detector SPECT system with a 241Am Transmission line source, Simultaneous Transmission/emission tomography (TCT/ECT) was performed on 60 patients with angiographic coronary disease and 59 patients with ≤5% likelihood of CHD. Iteratively reconstructed AC stress 99mTc-sestamibi perfusion images were compared with uncorrected (NC) filtered-backprojection images. Normal database polar maps were constructed from AC and NC images for quantitative analyses. From the low-likelihood patients, the visual and quantitative normalcy rates increased from 0.88 and 0.76 for NC to 0.98 and 0.95 for AC (P

  • Simultaneous Transmission emission myocardial perfusion tomography diagnostic accuracy of attenuation corrected 99mtc sestamibi single photon emission computed tomography
    Circulation, 1996
    Co-Authors: Edward P. Ficaro, Jeffrey A. Fessler, Paul D. Shreve, J.n. Kritzman, Patricia A. Rose, James R. Corbett
    Abstract:

    Background The purpose of the present study was to assess the diagnostic performance of attenuation-corrected (AC) stress 99mTc-sestamibi cardiac single-photon emission computed tomography (SPECT) for the identification of coronary heart disease (CHD). Methods and Results With a triple-detector SPECT system with a 241Am Transmission line source, Simultaneous Transmission/emission tomography (TCT/ECT) was performed on 60 patients with angiographic coronary disease and 59 patients with ≤5% likelihood of CHD. Iteratively reconstructed AC stress 99mTc-sestamibi perfusion images were compared with uncorrected (NC) filtered-backprojection images. Normal database polar maps were constructed from AC and NC images for quantitative analyses. From the low-likelihood patients, the visual and quantitative normalcy rates increased from 0.88 and 0.76 for NC to 0.98 and 0.95 for AC (P<.05). For the detection of CHD, the receiver operating characteristic curves for the AC images demonstrated improved discrimination capaci...

  • Simultaneous Transmission emission thallium 201 cardiac spect effect of attenuation correction on myocardial tracer distribution
    The Journal of Nuclear Medicine, 1995
    Co-Authors: Edward P. Ficaro, Jeffrey A. Fessler, James R. Corbett, Robert J Ackermann, W L Rogers, Markus Schwaiger
    Abstract:

    UNLABELLED: This study evaluates the effect of attenuation correction on regional myocardial tracer distributions defined by 201TI cardiac perfusion SPECT images obtained from healthy volunteers and patients with coronary heart disease. METHODS: A three-detector SPECT system equipped with an 241Am line source and a fanbeam collimator was used for Simultaneous Transmission/emission (201TI) tomography on 40 patients and 10 normal volunteers. Uncorrected emission images were reconstructed using filtered backprojection (FBP), whereas the attenuation corrected images were iteratively reconstructed with a regularized, least-squares algorithm utilizing the attenuation map computed from the Transmission data. Both sets of images were reoriented into short-axis and vertical long-axis slices. Circumferential profile analysis was applied to both datasets of short-axis slices. RESULTS: The normal volunteers demonstrated improved homogeneity in tracer distribution. For a basal short-axis slice, the lateral-to-posterior activity ratio improved from 1.17 +/- 0.12 for FBP to 1.01 +/- 0.07. Basal attenuation appeared properly compensated as the peak basal-to-apical slice activity gradient along the posterior-inferior wall changed from 1.15 +/- 0.12 for FBP to 1.01 +/- 0.09. The apex of the attenuation corrected images showed a significant decrease in activity relative to the base which appeared consistent with anatomic wall thinning. For the inferior and basal septal regions, the defect severity was slightly less in the attenuation corrected images, but the defects were more sharply defined compared to the FBP image defects. CONCLUSION: These results indicate that attenuation correction is clinically feasible and accurately corrects for photon attenuation. Clinical validation, however, is necessary to define the diagnostic benefits.

Edward P. Ficaro - One of the best experts on this subject based on the ideXlab platform.

  • Simultaneous Transmission/Emission Myocardial Perfusion Tomography Diagnostic Accuracy of Attenuation-Corrected 99mTc-Sestamibi Single-Photon Emission Computed Tomography
    Circulation, 1996
    Co-Authors: Edward P. Ficaro, Jeffrey A. Fessler, Paul D. Shreve, J.n. Kritzman, Patricia A. Rose, James R. Corbett
    Abstract:

    Background The purpose of the present study was to assess the diagnostic performance of attenuation-corrected (AC) stress 99mTc-sestamibi cardiac single-photon emission computed tomography (SPECT) for the identification of coronary heart disease (CHD). Methods and Results With a triple-detector SPECT system with a 241Am Transmission line source, Simultaneous Transmission/emission tomography (TCT/ECT) was performed on 60 patients with angiographic coronary disease and 59 patients with ≤5% likelihood of CHD. Iteratively reconstructed AC stress 99mTc-sestamibi perfusion images were compared with uncorrected (NC) filtered-backprojection images. Normal database polar maps were constructed from AC and NC images for quantitative analyses. From the low-likelihood patients, the visual and quantitative normalcy rates increased from 0.88 and 0.76 for NC to 0.98 and 0.95 for AC (P

  • Simultaneous Transmission emission myocardial perfusion tomography diagnostic accuracy of attenuation corrected 99mtc sestamibi single photon emission computed tomography
    Circulation, 1996
    Co-Authors: Edward P. Ficaro, Jeffrey A. Fessler, Paul D. Shreve, J.n. Kritzman, Patricia A. Rose, James R. Corbett
    Abstract:

    Background The purpose of the present study was to assess the diagnostic performance of attenuation-corrected (AC) stress 99mTc-sestamibi cardiac single-photon emission computed tomography (SPECT) for the identification of coronary heart disease (CHD). Methods and Results With a triple-detector SPECT system with a 241Am Transmission line source, Simultaneous Transmission/emission tomography (TCT/ECT) was performed on 60 patients with angiographic coronary disease and 59 patients with ≤5% likelihood of CHD. Iteratively reconstructed AC stress 99mTc-sestamibi perfusion images were compared with uncorrected (NC) filtered-backprojection images. Normal database polar maps were constructed from AC and NC images for quantitative analyses. From the low-likelihood patients, the visual and quantitative normalcy rates increased from 0.88 and 0.76 for NC to 0.98 and 0.95 for AC (P<.05). For the detection of CHD, the receiver operating characteristic curves for the AC images demonstrated improved discrimination capaci...

  • Simultaneous Transmission emission thallium 201 cardiac spect effect of attenuation correction on myocardial tracer distribution
    The Journal of Nuclear Medicine, 1995
    Co-Authors: Edward P. Ficaro, Jeffrey A. Fessler, James R. Corbett, Robert J Ackermann, W L Rogers, Markus Schwaiger
    Abstract:

    UNLABELLED: This study evaluates the effect of attenuation correction on regional myocardial tracer distributions defined by 201TI cardiac perfusion SPECT images obtained from healthy volunteers and patients with coronary heart disease. METHODS: A three-detector SPECT system equipped with an 241Am line source and a fanbeam collimator was used for Simultaneous Transmission/emission (201TI) tomography on 40 patients and 10 normal volunteers. Uncorrected emission images were reconstructed using filtered backprojection (FBP), whereas the attenuation corrected images were iteratively reconstructed with a regularized, least-squares algorithm utilizing the attenuation map computed from the Transmission data. Both sets of images were reoriented into short-axis and vertical long-axis slices. Circumferential profile analysis was applied to both datasets of short-axis slices. RESULTS: The normal volunteers demonstrated improved homogeneity in tracer distribution. For a basal short-axis slice, the lateral-to-posterior activity ratio improved from 1.17 +/- 0.12 for FBP to 1.01 +/- 0.07. Basal attenuation appeared properly compensated as the peak basal-to-apical slice activity gradient along the posterior-inferior wall changed from 1.15 +/- 0.12 for FBP to 1.01 +/- 0.09. The apex of the attenuation corrected images showed a significant decrease in activity relative to the base which appeared consistent with anatomic wall thinning. For the inferior and basal septal regions, the defect severity was slightly less in the attenuation corrected images, but the defects were more sharply defined compared to the FBP image defects. CONCLUSION: These results indicate that attenuation correction is clinically feasible and accurately corrects for photon attenuation. Clinical validation, however, is necessary to define the diagnostic benefits.

E Alsusa - One of the best experts on this subject based on the ideXlab platform.

  • PIMRC - A Simultaneous Transmission spatial modulation technique with optimum detection
    21st Annual IEEE International Symposium on Personal Indoor and Mobile Radio Communications, 2010
    Co-Authors: A Elkalagy, E Alsusa
    Abstract:

    A Simultaneous Transmission spatial modulation (SM) technique is introduced in this paper. Unlike in conventional SM where only one antenna transmits at a time, the Simultaneous spatial modulation (SSM) transmits from two antennas at the same time. The proposed technique utilizes a unique symbol to antenna assignment algorithm at the transmitter and the SM optimum detector at the receiver. The paper compares the performances of the proposed technique to those of the conventional and optimum SM techniques and V-BLAST. The results show that the proposed technique outperforms the conventional one in terms of BER performance under different channel conditions.

  • PIMRC - A novel spatial modulation technique with interference free Simultaneous Transmission
    21st Annual IEEE International Symposium on Personal Indoor and Mobile Radio Communications, 2010
    Co-Authors: A Elkalagy, E Alsusa
    Abstract:

    A performance-enhanced two-transmit antenna spatial modulation (SM) technique is introduced and analysed. Specifically, this paper modifies the conventional spatial modulation technique by utilising Simultaneous Transmission from two antennas, couple with the utilisation of short orthogonal codes for antenna identification. A unique symbol to antenna assignment to enable the receiver to distinguish between the different possible constellation points is also presented. To highlight the achieved gains, the paper compares the performances of the proposed technique to those of the conventional SM technique in OFDM systems. The results show that the proposed technique outperforms the conventional one in terms of BER performance. Furthermore we develop analytical analysis for the symbol error ratio (SER) of the proposed technique and show that the analytical and simulation results closely match.

  • A Simultaneous Transmission spatial modulation technique with optimum detection
    21st Annual IEEE International Symposium on Personal Indoor and Mobile Radio Communications, 2010
    Co-Authors: A Elkalagy, E Alsusa
    Abstract:

    A Simultaneous Transmission spatial modulation (SM) technique is introduced in this paper. Unlike in conventional SM where only one antenna transmits at a time, the Simultaneous spatial modulation (SSM) transmits from two antennas at the same time. The proposed technique utilizes a unique symbol to antenna assignment algorithm at the transmitter and the SM optimum detector at the receiver. The paper compares the performances of the proposed technique to those of the conventional and optimum SM techniques and V-BLAST. The results show that the proposed technique outperforms the conventional one in terms of BER performance under different channel conditions.

  • A novel spatial modulation technique with interference free Simultaneous Transmission
    21st Annual IEEE International Symposium on Personal Indoor and Mobile Radio Communications, 2010
    Co-Authors: A Elkalagy, E Alsusa
    Abstract:

    A performance-enhanced two-transmit antenna spatial modulation (SM) technique is introduced and analysed. Specifically, this paper modifies the conventional spatial modulation technique by utilising Simultaneous Transmission from two antennas, couple with the utilisation of short orthogonal codes for antenna identification. A unique symbol to antenna assignment to enable the receiver to distinguish between the different possible constellation points is also presented. To highlight the achieved gains, the paper compares the performances of the proposed technique to those of the conventional SM technique in OFDM systems. The results show that the proposed technique outperforms the conventional one in terms of BER performance. Furthermore we develop analytical analysis for the symbol error ratio (SER) of the proposed technique and show that the analytical and simulation results closely match.

  • A novel two-antenna spatial modulation technique with Simultaneous Transmission
    SoftCOM 2009 - 17th International Conference on Software Telecommunications & Computer Networks, 2009
    Co-Authors: A Elkalagy, E Alsusa
    Abstract:

    A performance-enhanced two-transmit antenna spatial modulation (SM) technique is introduced and analysed. Specifically, this paper modifies the conventional spatial modulation technique by utilising Simultaneous Transmission from both antennas to improve the diversity aspect and hence the system performance. A unique symbol to antenna assignment to enable the receiver to distinguish between the different possible constellation points is also presented. To highlight the achieved gains, the paper compares the performances of the proposed and conventional SM techniques in multipath fading channels. The results show that the proposed technique outperforms the conventional one in terms of BER performance. Turbo forward error correction coding is used to further highlight the achieved gains in a channel-coded system.

Chia-hsiung Chang - One of the best experts on this subject based on the ideXlab platform.

Yung-kuang Chen - One of the best experts on this subject based on the ideXlab platform.

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