Observations regarding scatter fraction and NEC measurements for small animal PET

Yongfeng Yang, Simon R Cherry

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

The scatter fraction (SF) was measured for a line source, a mouse-sized phantom (25 mm Φ × 70 mm) and a rat-sized phantom (60 mm Φ × 150 mm) on the microPET II small animal PET scanner. Measurements were performed for four lower energy thresholds of 150, 250, 350 and 450 keV and a fixed upper energy threshold of 750 keV. Four different methods were used to obtain the SF. Significant scatter fractions were measured with just the line source in the field of view, with the spatial distribution of these events consistent with scatter from the gantry and environment. For mouse imaging, this component dominates over object scatter, and the measured SF is strongly method dependent. The environmental SF rapidly increases as the lower energy threshold decreases and can be more than 20% for an open energy window of 150-750 keV. The object SF originating from the mouse phantom is about 4% and does not change significantly as the lower energy threshold changes. The object SF for the rat phantom ranges from 20-40% for different energy windows and increases as the lower energy threshold decreases. Because the measured SF is highly dependent on the method, and there is as yet no agreed upon standard for animal PET, care must be exercised when comparing NEC rates for small objects between different scanners. Differences may be methodological rather than reflecting the performance of the scanner. Furthermore, this data has implications for scatter correction methods when the majority of the detected scatter does not arise from the object itself.

Original languageEnglish (US)
Title of host publicationIEEE Nuclear Science Symposium Conference Record
EditorsJ.A. Seibert
Pages3906-3910
Number of pages5
Volume6
StatePublished - 2004
Event2004 Nuclear Science Symposium, Medical Imaging Conference, Symposium on Nuclear Power Systems and the 14th International Workshop on Room Temperature Semiconductor X- and Gamma- Ray Detectors - Rome, Italy
Duration: Oct 16 2004Oct 22 2004

Other

Other2004 Nuclear Science Symposium, Medical Imaging Conference, Symposium on Nuclear Power Systems and the 14th International Workshop on Room Temperature Semiconductor X- and Gamma- Ray Detectors
CountryItaly
CityRome
Period10/16/0410/22/04

Fingerprint

Rats
Animals
Spatial distribution
Imaging techniques

Keywords

  • MicroPET
  • Positron emission tomography (PET)
  • Scatter fraction
  • Small-animal imaging

ASJC Scopus subject areas

  • Computer Vision and Pattern Recognition
  • Industrial and Manufacturing Engineering

Cite this

Yang, Y., & Cherry, S. R. (2004). Observations regarding scatter fraction and NEC measurements for small animal PET. In J. A. Seibert (Ed.), IEEE Nuclear Science Symposium Conference Record (Vol. 6, pp. 3906-3910)

Observations regarding scatter fraction and NEC measurements for small animal PET. / Yang, Yongfeng; Cherry, Simon R.

IEEE Nuclear Science Symposium Conference Record. ed. / J.A. Seibert. Vol. 6 2004. p. 3906-3910.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Yang, Y & Cherry, SR 2004, Observations regarding scatter fraction and NEC measurements for small animal PET. in JA Seibert (ed.), IEEE Nuclear Science Symposium Conference Record. vol. 6, pp. 3906-3910, 2004 Nuclear Science Symposium, Medical Imaging Conference, Symposium on Nuclear Power Systems and the 14th International Workshop on Room Temperature Semiconductor X- and Gamma- Ray Detectors, Rome, Italy, 10/16/04.
Yang Y, Cherry SR. Observations regarding scatter fraction and NEC measurements for small animal PET. In Seibert JA, editor, IEEE Nuclear Science Symposium Conference Record. Vol. 6. 2004. p. 3906-3910
Yang, Yongfeng ; Cherry, Simon R. / Observations regarding scatter fraction and NEC measurements for small animal PET. IEEE Nuclear Science Symposium Conference Record. editor / J.A. Seibert. Vol. 6 2004. pp. 3906-3910
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