Ultrafast CT can produce clearer images in the ED

Utilizing the ultrafast scan mode for CT imaging in the emergency department (ED) can significantly reduce motion artifacts, reported a team of Japan-based researchers in a study published by the American Journal of Roentgenology.

“Under emergency department conditions, image quality is often compromised because of respiratory or cardiac motion artifacts,” wrote Tomko Takayanagi, with the University of Tokyo Graduate School of Medicine’s Department of Radiology and colleagues. “These artifacts not only degrade image quality but also are sometimes mistaken for pathologic changes, such as bronchiectasis and aortic dissection.”

The researchers set out to retrospectively determine if ultrafast whole-body CT images resulted in fewer motion artifacts compared to images taken with a conventional scanner.

Takayanagi et al. included the images of 60 unconscious patients, 30 of whom underwent CT with a new generation scanner in ultrafast mode. The other 30 had been imaged with a traditional CT scanner. A pair of radiologists independently reviewed motion artifacts in the aorta, lung, diaphragm, liver and kidneys; they were graded based on severity using a 4-point scale.

Overall, images from the new generation scanner in ultrafast mode greatly reduced motion artifacts. This was especially true in the lower lungs, diaphragm, liver, kidneys and aortic root.

The aortic root is highly susceptible to motion-related artifacts, but the improvements in reducing such artifacts in this study suggest the ultrafast method will improve the rate of accurate aortic dissection diagnoses—a rare but “clinically devastating” condition.

Interobserver agreement on motion artifact ratings was “good,” but the researchers reported no differences in clarify between each scanning method for the aortic arch, thoracic descending aorta, abdominal aorta and upper lungs.

Limitations must be taken into consideration when analyzing these results, the researchers noted. For example, images were taken from a single center and the study was not prospective nor randomized.

Despite this, the researchers believe their method can improve patient care.

“CT images obtained in the ultrafast scan mode in the evaluation of unconscious patients had a significant reduction in motion artifacts,” the researchers added. “The ultrafast technique is expected to be useful for diagnostic CT in the emergency department.”