Clinical application of monoenergetic technique of dual-energy CT in the fractures fixed with metal fixer

Objective: To analyze the clinical application of monoenergetic technique of dual-energy CT in removing metal artifacts for patients with fractures fixed with metal fixer. Methods: Forty-five patients with fractures fixed with metal fixer underwent dual-energy CT scanning for the fractures. Two different data were collected in one-time scanning using dual-energy scanning sequence. With monoenergetic technique, two different data at 100 and 140 kilovolt.s were used for subtraction to removing metal artifacts based on different densities. Raw data were reconstructed with monoenergetic technique (group A) and conventional simulation method (group B), respectively. And, all data were reconstructed with multiplanar reconstruction (MPR), volume rendering (VR) and maximum intensity projection (MIP), respectively. Wilcoxon, signed rank test was applied for the comparison of imaging quality and artifacts between the two groups. Results: There were fewer artifacts on the images due to the application of monoenergetic technique in dual energy CT scanning. In group A, the rate of high-quality images reached to 91.9% (124/135); and, in group B, it was 59.3% (80/135). There were statistical difference between the two groups (Z=-12.541, P< 0.01). The images without artifact reached to 89.6% (121/135) in group A; whereas, it was 45.2% (61/135) in group B. There was statistical difference between the two groups (Z=-11.910, P<0.01). Conclusion: Using monoenergetic technique, metal artifacts were removed effectively and the fine structure of fracture was clearly displayed. (authors)