Search Results - "Gifford, H. C."

Evaluation of Multiclass Model Observers in PET LROC Studies by Gifford, H. C., Kinahan, P. E., Lartizien, C., King, M. A.

“…A localization ROC (LROC) study was conducted to evaluate nonprewhitening matched-filter (NPW) and channelized NPW (CNPW) versions of a multiclass model…”
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Efficient visual-search model observers for PET by Gifford, H C

“…Scanning model observers have been efficiently applied as a research tool to predict human-observer performance in F-18 positron emission tomography (PET). We…”
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Channelized Hotelling and Human Observer Correlation for Lesion Detection in Hepatic SPECT Imaging by Gifford, Howard C, King, Michael A, de Vries, Daniel J, Soares, Edward J

“…Mathematic "model" observers that predict human performance are of interest in medical imaging as substitutes in psychophysical studies. We have examined the…”
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A comparison of human observer LROC and numerical observer ROC for tumor detection in SPECT images by Gifford, H.C., Wells, R.G., King, M.A.

“…Numerical observers that predict human performance in medical detection tasks can relieve some of the burden of conducting psychophysical studies. Research for…”
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Single-slice versus multi-slice display for human-observer lesion-detection studies by Wells, R.G., King, M.A., Gifford, H.C., Pretorius, P.H.

“…Use of a single-slice (2D) display for observer studies may bias results acid reduce the studies' clinical generalizability. Human observers perform better at…”
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A comparison of human and model observers in multislice LROC studies by Gifford, H.C., King, M.A., Pretorius, P.H., Wells, R.G.

“…Model and human observers have been compared in a series of localization receiver operating characteristic (LROC) studies involving single-slice and multislice…”
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Influence of fertilizer and sewage sludge compost on yield and heavy metal accumulation by lettuce grown in urban soils by Sterrett, S B, Chaney, R L, Gifford, C H, Mielke, H W

“…Previous research has demonstrated that many urban soils are enriched in Pb, Cd and Zn. Culture of vegetable crops in these soils could allow transfer of…”
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Estimation of the Rigid-Body Motion From Three-Dimensional Images Using a Generalized Center-of-Mass Points Approach by Feng, B., Bruyant, P.P., Pretorius, P.H., Beach, R.D., Gifford, H.C., Dey, J., Gennert, M.A., King, M.A.

“…We present an analytical method for the estimation of rigid-body motion in sets of three-dimensional (3-D) SPECT and PET slices. This method utilizes…”
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EM clustering for holistic search in human-model observers by Gifford, H C, King, M A

“…Mathematical models of human observers for detection tasks are of interest in medical imaging analysis, but current model observers have limitations related to…”
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Reducing Artifacts in Pelvic Bone SPECT: An Assessment of Lesion Detectability Using Numerical and Human Observers by Farncombe, T.H., Gifford, H.C., King, M.A.

“…In pelvic bone SPECT using Tc-99m labeled compounds, physical effects such as nonhomogeneous attenuation and the accumulation of activity into the bladder…”
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Optimization of regularization of attenuation and scatter-corrected (99m)Tc cardiac SPECT studies for defect detection using hybrid images by Narayanan, M V, King, M A, Leppo, J, Dahlbert, S, Pretorius, P H, Gifford, H C

“…Through means of a receiver-operating-characteristics study, we optimize the iteration number and three-dimensional (3-D) Gaussian postfiltering of (99m)Tc…”
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A Multiclass Model Observer for Multislice-Multiview Images by Gifford, H.C., Lehovich, A., King, M.A.

“…A human-model observer for tumor detection-localization studies featuring multislice-multiview (or volumetric) image displays has been introduced. This…”
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Impact of respiratory motion on the detection of small pulmonary nodules in SPECT imaging by Smyczynski, M. S., Gifford, H. C., Lehovich, A., McNamara, J. E., Segars, W. P., Tsui, B. M. W., King, M. A.

“…The objective of this investigation is to determine the impact of respiratory motion on the detection of small solitary pulmonary nodules (SPN) in single…”
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LROC analysis of detector-response compensation in SPECT by Gifford, H.C., King, M.A., Wells, R.G., Hawkins, W.G., Narayanan, M.V., Pretorius, P.H.

“…Localization ROC (LROC) observer studies examined whether detector response compensation (DRC) in ordered-subset, expectation-maximization (OSEM)…”
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An evaluation of iterative reconstruction strategies on mediastinal lesion detection using hybrid Ga-67 SPECT images by Pereira, N. F., Gifford, H. C., Pretorius, P. H., Farncombe, T., Smyczynski, M., Licho, R., Schneider, P., King, M. A.

“…Hybrid LROC studies can be used to more realistically assess the impact of reconstruction strategies, compared to those constructed with digital phantoms. This…”
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A five-dimensional mathematical model for regional and global changes in cardiac uptake and motion by Pretorius, P.H., King, M.A., Gifford, H.C.

“…The objective of this work was to simultaneously introduce known regional changes in contraction pattern and perfusion to the existing gated Mathematical…”
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Factors Influencing Lesion Detection in SPECT Lung Images by Gifford, H.C., Zheng, X.M., Licho, R., Pretorius, P.H., Schneider, P.B., Simkin, P.H., King, M.A.

“…An earlier localization ROC (LROC) study that found attenuation correction (AC) degraded the detection of solitary pulmonary nodules (SPN) in hybrid SPECT lung…”
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Maximizing the detection and localization of Ga-67 tumors in thoracic SPECT MLEM(OSEM) reconstructions by Wells, R.G., Simkin, P.H., Judy, P.F., King, M.A., Pretorius, P.H., Gifford, H.C., Schneider, P.

“…Iterative reconstruction algorithms are usually regularized by applying a penalty function, by post-filtering, or by halting the algorithm after some number of…”
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Effect of block-iterative acceleration on Ga-67 tumor detection in thoracic SPECT by Gifford, H.C., King, M.A., Narayanan, M.V., Pretorius, P.H., Smyczynski, M.S., Wells, R.G.

“…A combination of human localization receiver operating characteristic (LROC) and channelized Hotelling observer (CHO) ROC psychophysical studies were used to…”
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The impact of ROI definition on estimator performance on FBP reconstructed Ga-67 SPECT images by Wells, R.G., Gifford, H.C., King, M.A.

“…Quantitative accuracy of reconstructed images depends not only on the reconstruction strategy, but also on the definition of the estimator. The authors…”
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