Assessment of energy-weighted acquisition in SPECT using ROC analysis.
Energy-weighted acquisition is a technique for reducing Compton scatter effects in nuclear medicine images. The effect of energy-weighted acquisition on SPECT99mTc images was evaluated by comparing the energy-weighted acquisition images with those obtained using a 20% photopeak energy window.


METHODS
SPECT images were compared using receiver operator characteristic (ROC) experiments testing the observer's ability to perform a pseudoclinical task. The tasks were detecting cold lesions within a uniform background and cold lesions within images created with a tomographic brain phantom.


RESULTS
ROC analysis for each phantom produced different results. No significant difference was found between the two acquisition techniques in detecting cold lesions on uniform backgrounds. Energy-weighted acquisition improved cold lesion detection significantly within the brain phantom in comparison with 20% photopeak acquisition.


CONCLUSIONS
Lesion detection in 99mTcSPECT images can be improved using energy-weighted acquisition. This improvement, however, is dependent on the nature of the object being imaged. Images with structure show improved detection, whereas uniform images do not.
Department of Bio-Medical Physics and Bio-Engineering, University of Aberdeen, Scotland.
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RT
Staff
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HG
Gemmell
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Sharp
D001921:Brain / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D019047:Phantoms, Imaging; D012372:ROC Curve; D012542:Scattering, Radiation; D013667:Technetium; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
D013667:Technetium