Table 1.

Summary of the characteristics of carbon dioxide and against iodinated contrast agents

Characteristics	Carbon dioxide	Iodinated contrast agents
Overall sensitivity	Less	Higher
Overall specificity	Less	Higher
Nephrotoxicity	No	Yes
Allergenic	No	Yes
Cost	Low	High
Ease of administration	Cumbersome	Easier
Limitations	Visibility and air contamination	Dose related toxicity and allergy
Delivery via small caliber catheters	Possible	Difficult
Radiation exposure	Increased if digital subtraction angiography used	Standard
Dose	Rate related toxicity	Volume related nephrotoxicity
Contraindications	Pulmonary-systemic communications; not for use in heart, brain or spinal vasculature	Allergy, nephrotoxicity
Hepatotoxicity	Rare	Rare
Quality of image	Good	Better
Procedure duration	Increased	Standard