PT  - JOURNAL ARTICLE
AU  - Philip Aschoff
AU  - Christian Plathow
AU  - Matthias Lichy
AU  - Gunter Erb
AU  - Christina Pfannenberg
TI  - The influence of high concentrated iodinated intravenous contrast media on the attenuation correction of FDG-PET/CT in the evaluation of liver lesions
DP  - 2009 May 01
TA  - Journal of Nuclear Medicine
PG  - 1489--1489
VI  - 50
IP  - supplement 2
4099  - http://jnm.snmjournals.org/content/50/supplement_2/1489.short
4100  - http://jnm.snmjournals.org/content/50/supplement_2/1489.full
SO  - J Nucl Med2009 May 01; 50
AB  - 1489 Objectives In PET/CT intravenous contrast media (CM) with high iodine concentration is mandatory for the evaluation of liver lesions by the concomitant CT but it can alter the CT based attenuation correction (AC). We evaluated the influence of this effect on the diagnostic accuracy of the FDG-PET. Methods Prospective evaluation of FDG-PET/CT of 25 patients with suspicion of malignant liver lesions including a multiphasic CT with CM (Iomeron, 400 mg iodine/ml, Bracco, Germany). AC based on CT without CM (n-PET, standard of reference) and with CM in arterial (art-PET), portovenous (pv-PET) and late phase (late-PET). Intraindividual comparison of the visual assessment of all liver lesions and quantitative evaluation (SUVavg) of up to 3 liver lesions per patient. Results No differences were found for the visual assessment of PET with AC based on CT with or without CM. Notably there were no false positives or false negatives due to PET-artifacts from contrast enhancing structures. 53 liver lesions were evaluated quantitatively: the mean SUVavg in n-PET was 4.4 (SD 3.4), the mean differences for art-PET, pv-PET and late-PET were +0.1, +0.3 and +0.3 representing a mean absolute error of 7%, 8% and 8%. The mean SUVavg of normal liver in n-PET was 2.6 (SD 0.5), the mean differences for art-PET, pv-PET and late-PET were +0.1, +0.2 and +0.2 representing a mean absolute error of 7%, 10% and 7%. Conclusions Contrast enhanced CT using CM with high iodine concentration can be used for attenuation correction in PET/CT for the evaluation of liver lesions. It does not affect the diagnostic accuracy of the visual assessment of the PET and the influence on the quantitative evaluation is low.