Comparison of helical and conventional chest CT in the uncooperative pediatric patient

The objective of this study was to compare the quality of conventional and helical computed tomography (CT) images in children unable to breath-hold. Sixteen patients (age range 1.1-7.5 years) underwent both conventional and helical chest CT on a General Electric HiSpeed Advantage scanner at a mean study interval of 3.8 months. Conventional 0.6-s scans were reconstructed with standard algorithm while 1.0-s helical studies were reconstructed with standard and bone algorithms. Three blinded observers retrospectively evaluated the images. There was no significant difference in motion, image sharpness and anatomic resolution for helical and conventional scans reconstructed with standard algorithm. Furthermore, image sharpness (P < 0.001) and visibility of bronchi (P < 0.001) were improved when helical images were reconstructed with bone algorithm. We conclude that motion artifact severity, image sharpness and anatomic resolution for helical and conventional 0.6-s chest CT are similar when the images are reconstructed with an identical algorithm. Helical CT may be preferable because of the faster examination times and the ability to reconstruct overlapping images as an adjunct for problem solving. Also, with the scanner used, bone algorithm reconstruction can be employed to improve image sharpness and anatomic resolution.