Whole-body imaging of oncologic patients using 16-channel PET-CT. Evaluation of an i.v. contrast enhanced MDCT protocol.
OBJECTIVE
This study evaluated a MDCT protocol for contrast-enhanced 16-channel PET-CT with regard to scan range and duration of a whole-body (18)F-FDG PET-CT examination, the occurrence of contrast-material induced artefacts and quantitative assessment of CT attenuation.


METHODS
205 patients (51.9+/-12.4 years) with different malignant tumours underwent whole-body PET-CT; the study protocol had been approved by the institutional review board. Contrast-enhanced MDCT (16 x 1.5 mm; 120 ml Iomeprol 3 ml/s, 50 ml saline chaser bolus, scan delay 70 s; oral contrast) was also used for attenuation correction. From MDCT data mean scan range and duration, occurrence of contrast media-induced artefacts, and mean CT densities of jugular (jv) and subclavian (scv), superior (vcs) and inferior (vci) caval, portal (pv), and bilateral external iliac veins, pulmonary (ap) and iliac arteries, descending thoracic and abdominal aorta, all cardiac chambers, as well as both liver lobes, spleen, adrenal glands and kidneys were determined.


RESULTS
Attenuation corrected PET images were free of contrast media-related image artefacts. Homogeneous contrast enhancement was found in the mediastinal veins (right/left jv 171+/-34/171+/-35, scv 127+/-50/127+/-40, vcs 153+/-36 HU) and arteries (e.g. ap 145+/-26/151+/-26). Cardiac chambers, abdominal vessels (e.g. vci 138+/-24, pv 159+/-25 HU), and parenchymal organs revealed sufficient and homogenous contrast-enhancement in all cases. No beam-hardening artefacts occurred in the neighbourhood of the subclavian veins.


CONCLUSIONS
The chosen whole-body (18)F-FDG 16-slice PET-CT protocol allowed for craniocaudal CT scanning with high vessel and parenchymal contrast revealing no IV contrast-media induced artefacts in attenuation-corrected PET data sets.
Juergens
K U
KU
Department of Clinical Radiology, University of Muenster, Albert-Schweitzer-Strasse 33, 48149 Muenster, Germany. kujuerg@uni-muenster.de
Oei
M L
ML
Weckesser
M
M
Franzius
C
C
Wormanns
D
D
Schober
O
O
Heindel
W
W
D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging; D003287:Contrast Media; D005260:Female; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography; D014057:Tomography, X-Ray Computed; D051598:Whole Body Imaging / Q000379:methods*
D003287:Contrast Media