Dual-head gamma camera 2-[fluorine-18]-fluoro-2-deoxy-D-glucose positron emission tomography in oncological patients: effects of non-uniform attenuation correction on lesion detection.
The purpose of this study was to evaluate a dual head coincidence gamma camera (DH-PET) equipped with single-photon transmission for 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) imaging in oncological patients. Forty-five patients with known or suspected malignancies, scheduled for a positron emission tomography (PET) scan, were first studied with a dedicated ring PET and subsequently with DH-PET. All patients underwent measured attenuation correction using germanium-68 rod sources for ring PET and caesium-137 sources for DH-PET. Ring PET emission scan was started 64+/-17 min after intravenous administration of 235+/-42 MBq FDG. DH-PET emission followed 160+/-32 min after i.v. FDG. Attenuation-corrected and non-attenuation-corrected images were reconstructed for ring PET and DH-PET. The image sets were evaluated independently by three observers blinded to clinical data and to results of conventional imaging. Attenuation-corrected ring PET as the standard of reference depicted 118 lesions, non-attenuation-corrected ring PET 113 (96%) lesions, and attenuation-corrected DH-PET and non-attenuation-corrected DH-PET, 101 (86%) and 84 (71%) lesions, respectively (P<0.05). The lesion detection rate of attenuation-corrected and non-attenuation-corrected DH-PET was almost similar for lesions >20 mm, whereas attenuation correction increased the detection rate from 60% to 80% for lesions </=20 mm (P<0.01). A patient-based analysis revealed concordant results relative to attenuation-corrected ring PET for non-attenuation-corrected ring PET, attenuation-corrected DH-PET and non-attenuation-corrected DH-PET in 42 (93%), 36 (80%) and 31 (69%) patients, respectively. Differences might have influenced patient management in two (4%), six (13%) and ten (22%) patients, respectively. In conclusion, measured attenuation correction markedly improves the lesion detection capability of DH-PET. With measured attenuation correction the diagnostic performance of DH-PET is closer to that of dedicated ring PET.
Zimny
M
M
Department of Nuclear Medicine, University Hospital, Aachen University of Technology, Pauwelsstrasse 30, D-52074 Aachen, Germany.
Kaiser
H J
HJ
Cremerius
U
U
Reinartz
P
P
Schreckenberger
M
M
Sabri
O
O
Buell
U
U
D005069:Evaluation Studies as Topic; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D015902:Gamma Cameras; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008875:Middle Aged; D009369:Neoplasms / Q000000981:diagnostic imaging*; D019275:Radiopharmaceuticals; D014055:Tomography, Emission-Computed / Q000295:instrumentation / Q000379:methods
D005462:Fluorine Radioisotopes; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18