Clinical intra-arterial digital subtraction imaging. Use of small volumes of iodinated contrast material or carbon dioxide.

Abstract

Forty patients were examined with intra-arterial digital subtraction angiography (DSA) using meglumine iothalamate (202 mg iodine/ml) or CO2 as a contrast medium. Diagnostic studies were obtained in all patients. The use of CO2 resulted in diagnostic examinations of the common femoral artery to the level of the trifurcation. The use of CO2 and low-iodine-content contrast material reduced the iodine dosage, and temporal bandpass filtration DSA permitted a lower entrance exposure than pulsed systems. It is concluded that intra-arterial DSA, using the techniques described in this paper, will become a more important and widely used procedure than it currently is.

Carbon Dioxide in Vascular Imaging and Intervention

“…In 1982, HAWKINS (15) reported favorable results using C02-DSA imaging of visceral and extremity circulations in 20 patients. Since then, several reports, concerning the techniques and pathophysiologic effects as well as clinical applications, have established the role of C 0 2 gas as a negative contrast medium in angiography (7,12,26,33,34,43). Today, C02-DSA has become a new and promising technique, which provides accurate and useful vascular images with minor risks (Figure).…”

“…Injection of C 0 2 in C02-DSA can be performed either manually or automatically. For manual injection, 35 or 60 cm3 plastic syringes are filled from a medical grade C 0 2 gas tank after flushing with C 0 2 4 to 6 times and then attached to the catheter (15, 26,31,33,39,41). A standard mechanical injector can be also used for C 0 2 angiography, with two 3-way stopcocks which allow a closed system of C 0 2 delivery (6).…”

“…When using a mechanical injector, 50 to 70 cc of C 0 2 gas are usually delivered at a rate of 140 cc/s for aortic or renal arterial studies, while 20 to 40 cc at 40 cc/s are used for peripheral arteries (12, 34). When using a manual injector, C 0 2 gas should be rapidly injected with total volume of 15 to 75 cc of C 0 2 gas, at 15 to 35 cc/s flows for the aorta and larger arteries and at 12 to 16 cc/s flows for selective injections (15,26,39,43). In TIPS procedures, very rapid, nearly instantaneous injection of a relative large volume of C 0 2 gas is necessary to yield good image quality (31).…”

“…By application of C 0 2 gas and digital subtraction technique, highquality arteriographic images can be obtained of the abdominal aorta and of visceral, renal and leg arteries. Usually, the imaging speed is set at 3 to 6 exposuresh (43), although up to 30 frameds have been used in C02-DSA for special purposes (26). Occasionally, the quality of the final picture can be improved by using postprocessing with a "stacking" software program for compiling multiple digital images into a single composite image (12, 34).…”

“…bolus injection of glucagon (0.5 mg) before C02-DSA to decrease the effects of bowel gas motion (12, 34). The glucagon dose can be repeated up to 3 times (26). If large volumes of C 0 2 gas are required, pH and PC02 as well as PO2 should be closely monitored during the whole procedure of C02-DSA, especially in patients with respiratory diseases (15).…”