High-pitch carbon dioxide contrasted CT angiography: pilot study.
OBJECTIVE
This study was designed to evaluate CO2 computed tomography angiography (CO2-CTA) of the iliac and lower limb arteries in patients with contraindications for iodinated contrast agent (ICA).


METHODS
Five patients with contraindications for ICA were examined using CO2-fluoroscopic enhanced angiography (CO2-FLA) and CO2-CTA using a high-pitch examination protocol. Objective (vessel diameter) and subjective (visual score) image quality parameters were evaluated. Pathological findings in both modalities were compared.


RESULTS
CO2-CTA was feasible in all patients without adverse side effects, except for CO2 injection-associated pain. Objective vessel analysis revealed no significant difference in diameters as determined by CO2-CTA and CO2-FLA (0.44 ± 0.4 and 0.46 ± 0.41 mm, p = 0.93). CO2-CTA had on average a higher image-quality score (2.6 ± 1.0 vs. 2.3 ± 1.0, p = 0.009). While for pelvic and upper leg CO2-CTA advantageous (3.1 ± 0.74 vs. 2.7 ± 0.9, p = 0.0014) at good quality scores, for calf vessels no significant improvement was visible (1.9 ± 1.0 vs. 1.7 ± 0.9, p = 0.49) and scores were poorer.


CONCLUSIONS
CO2-CTA with high-pitch CT was feasible in a limited number of patients. Image-quality scores were on average higher for CO2-CTA than for CO2-FLA, while limited imaging quality in the vessels below the knee needs further work on the CT protocol. An added value of cross-sectional imaging was apparent but needs further quantification.
Department of Diagnostic and Interventional Radiology, RWTH Aachen University Hospital, Pauwelsstr. 30, Aachen, Germany, tpenzkofer@ukaachen.de.
Tobias
T
Penzkofer
Karin
K
Slebocki
Jochen
J
Grommes
Philipp
P
Bruners
Peter
P
Isfort
Thomas
T
Schmitz-Rode
Stephan
S
Langer
Christiane K
CK
Kuhl
Andreas H
AH
Mahnken
D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction / Q000379:methods*; D002245:Carbon Dioxide; D000075202:Contraindications; D003287:Contrast Media; D005260:Female; D006801:Humans; D007083:Iliac Artery / Q000000981:diagnostic imaging; D007457:Iodine Radioisotopes; D035002:Lower Extremity / Q000098:blood supply / Q000000981:diagnostic imaging; D008297:Male; D016491:Peripheral Vascular Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology; D010865:Pilot Projects; D011857:Radiographic Image Interpretation, Computer-Assisted; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
D003287:Contrast Media; D007457:Iodine Radioisotopes; D002245:Carbon Dioxide