Impact of Acquisition Geometry, Image Processing, and Patient Size on Lesion Detection in Whole-Body 18F-FDG PET

• DOI: 10.2967/jnumed.108.007369
• Publication Date: 2007-11-16T01:47:16Z
• Authors: G. El Fakhri; P. A. Santos; R. D. Badawi; C. H. Holdsworth; A. D. Van Den Abb...; M. F. Kijewski
• Keywords: 03 medical and health sciences; Imaging, Three-Dimensional; 0302 clinical medicine; Fluorodeoxyglucose F18; Neoplasms; Positron-Emission Tomography; Image Processing, Computer-Assisted; Humans; Whole Body Imaging; Radiopharmaceuticals; Body Mass Index

The aim of this work was to develop a rigorous evaluation methodology assess performance different acquisition and processing methods for variable patient sizes in the context lesion detection whole-body (18)F-FDG PET.Fifty-nine bed positions were acquired 32 patients 2-dimensional (2D) 3-dimensional (3D) modes 1-4 h after injection (740 MBq) using BGO PET scanner. Three spheres (1.0-, 1.3-, 1.6-cm diameter) containing (68)Ge also imaged separately air, at locations corresponding possible sites 2D 3D (590 targets per condition). Each position 7 min 6 corrected randoms delayed window subtraction (DWS) or variance reduction (RVR). Sphere sinograms attenuated attenuation map derived from transmission scan patient, scaling with identical factors ensure marginal detectability. Resulting reconstructed filtered backprojection (FBP) ordered-subsets expectation maximization (OSEM) without any scatter correction (FBP-NATS OSEM-NATS) FBP (FBP-ATT) attenuation-weighted OSEM (AWOSEM). processed identically Fourier rebinning. Next, volumes compared on basis 3-channel Hotelling observer (CHO-SNR [SNR is signal-to-noise ratio]) detecting presence sphere unknown size an anatomic background while modeling noise. noise equivalent count (NEC) rate computed 3 phantoms (40, 60, 95 kg) SNR.3D imaging yielded better detectability than (P < 0.025, 2-tailed paired t test) normal (body mass index [BMI] = 31). However, large (BMI > 31), as deteriorated 0.05). similar results sizes. CHO-SNR 40% greater AWOSEM, FBP-ATT, FBPNAT 0.05), AWOSEM significantly did FBP. In all patients, RVR systematic improvement over DWS both 3D. radicalNEC characterized by behavior that SNR(CHO) phantom considered study.