Accuracy of combined PET/CT in image-guided interventions of liver lesions: an ex-vivo study.
OBJECTIVE
Positioning of interventional devices in liver lesions is a challenging task if only CT is available. We investigated the potential benefit of combined PET/CT images for localization of interventional devices in interventional liver studies.


METHODS
Thirty lesions each of hyperdense, isodense and hypodense attenuation compared to normal liver parenchyma were injected into 15 ex-vivo pig livers. All lesions were composed of the same amounts of gelatine containing 0.5 MBq of (18)F-FDG. Following lesion insertion, an interventional needle was placed in each lesion under CT-guidance solely. After that, a PET/CT study was performed. The localization of the needle within the lesion was assessed for CT alone and PET/CT and the root mean square (RMS) was calculated. Results were compared with macroscopic measurements after lesion dissection serving as the standard of reference.


RESULTS
In hypo- and isodense lesions PET/CT proved more accurate in defining the position of the interventional device when compared with CT alone. The mean RMS for CT and PET/CT differed significantly in isodense and hypodense lesions. No significant difference was found for hyperdense lesions.


CONCLUSIONS
Combined FDG-PET/CT imaging provides more accurate information than CT alone concerning the needle position in FDG-PET positive liver lesions. Therefore combined PET/CT might be potentially beneficial not only for localization of an interventional device, but may also be beneficial for guidance in interventional liver procedures.
Veit
Patrick
P
Department of Diagnostic and Interventional Radiology, University Hospital of Essen, Hufelandstrasse 55, 45122 Essen, Germany. patrick.veit@uni-essen.de
Kuehle
Christiane
C
Beyer
Thomas
T
Kuehl
Hilmar
H
Bockisch
Andreas
A
Antoch
Gerald
G