Spiral CT with ionic and nonionic contrast material: evaluation of patient motion and scan quality.

Abstract

To assess the effect of rapidly injected ionic or nonionic contrast material on patient motion and scan quality in spiral computed tomography (CT). One hundred nine patients were prospectively, randomly chosen to receive ionic or nonionic contrast material. An acrylic rod was attached to the anterior abdomen with tape, which allowed an objective measurement of motion. Abdominal spiral CT was performed after intravenous injection of contrast material at a rate of 0.9 g of iodine per second. Scans were evaluated subjectively and objectively for motion and subjectively for quality. Complete data were available in 98 patients (47 in the ionic and 51 in the nonionic group). The acrylic rod moved an average of 0.44 mm per section in the nonionic group and 0.71 mm per section in the ionic group. Both subjective and objective measurements showed a statistically significant difference in patient motion. Use of nonionic contrast material resulted in less patient motion. Scan quality was better with nonionic contrast material. Less patient motion occurs and scan quality improves when spiral CT is performed with nonionic contrast material.