VENOGRAPHY WITH CARBON-DIOXIDE AS A CONTRAST AGENT

Purpose: The purpose of this study was to evaluate the feasibility, sa fety, and potential role of carbon dioxide (CO2) as a contrast agent f or venography. Methods: Consecutive patients with contraindications to iodinated contrast agents or with unsatisfactory iodinated contrast s tudies underwent CO2 digital subtraction venography. The images were r ated by three experienced angiographers. image quality and complicatio ns were assessed. Results: Over a 14-month period, 66 vein segments we re studied in 21 patients. There was good correlation between experien ced angiographers on CO2 image quality (R(i) = 0.80) and good agreemen t on diagnosis (k = 0.62). In 91% of the vein segments evaluated with CO2 there was interobserver agreement on the diagnosis. Upper extremit y veins were adequately imaged with CO2 alone in all (6/6) patients wi th contraindications to iodinated contrast. Following suboptimal iodin ated contrast studies in six patients, CO2 produced significantly bett er quality upper extremity central vein images (p < 0.05). Pain follow ing injection into peripheral veins was the only CO2-related complicat ion. Inferior vena cava (IVC) filters were successfully de ployed with CO2 alone in 78% (7/9) of patients; two required iodinated contrast. Conclusion: Based upon initial experience, CO2 venography can be recom mended in patients with contraindications to iodinated contrast or uns atisfactory iodinated contrast studies.