High-resolution computed tomography with 16-row mdct: a comparison regarding visibility and motion artifacts of dose-modulated thin slices and “step and shoot” images

Background: Dose modulation can be used to reduce the radiation dose in computed tomography (CT) examinations while still obtaining the necessary diagnostic image quality. Multidetector-row computed tomography (MDCT) provides the possibility of simultaneous reconstruction of thin and thick slices from the same raw data. Purpose: To compare thin slices reconstructed from a dose-modulated helical acquisition and conventional high-resolution computed tomography (HRCT) images taken with the “step and shoot” technique in terms of visibility and motion artifacts, in order to investigate the possibility of excluding “step and shoot” acquisition from the HRCT examination. Material and Methods: Twenty patients were examined by a dose-modulated helical acquisition, “MDCT smart mA,” and by a noncontiguous cross-sectional high-resolution 16-row MDCT examination, “MDCT step and shoot.” Images from four anatomical levels, made anonymous regarding identity and technical data, were analyzed in random order by four thoracic radiologists. Results: “MDCT smart mA” was worse than “MDCT step and shoot” in terms of visibility. Concerning motion artifacts, “MDCT smart mA” was better than “MDCT step and shoot.” Conclusion: Thin images reconstructed from a dose-modulated 16-row helical MDCT acquisition (“MDCT smart mA”), as performed in our study, do not provide sufficient image quality regarding visibility compared to the “MDCT step and shoot” technique for the latter technique to be excluded from the HRCT examination.

[1]  H. Hatabu,et al.  High-resolution CT using MDCT: comparison of degree of motion artifact between volumetric and axial methods. , 2004, AJR. American journal of roentgenology.

[2]  K. L. Lewis,et al.  Interstitial Lung Disease: Effects of Thin-Section CT on Clinical Decision Making , 2007 .

[3]  J. Mayo,et al.  Radiation exposure at chest CT: a statement of the Fleischner Society. , 2003, Radiology.

[4]  J. Hanley,et al.  The meaning and use of the area under a receiver operating characteristic (ROC) curve. , 1982, Radiology.

[5]  M Båth,et al.  Visual grading characteristics (VGC) analysis: a non-parametric rank-invariant statistical method for image quality evaluation. , 2007, The British journal of radiology.

[6]  W. Steinbrich,et al.  Image quality from high-resolution CT of the lung: comparison of axial scans and of sections reconstructed from volumetric data acquired using MDCT. , 2005, AJR. American journal of roentgenology.

[7]  M. Ruschin,et al.  A software tool for increased efficiency in observer performance studies in radiology. , 2005, Radiation protection dosimetry.

[8]  J. Remy,et al.  Assessment of diffuse infiltrative lung disease: comparison of conventional CT and high-resolution CT. , 1991, Radiology.

[9]  Catherine Beigelman-Aubry,et al.  Multi-detector row CT and postprocessing techniques in the assessment of diffuse lung disease. , 2005, Radiographics : a review publication of the Radiological Society of North America, Inc.

[10]  M F Reiser,et al.  Electrocardiographically gated thin-section CT of the lung. , 1999, Radiology.

[11]  A Crispin,et al.  Multislice helical CT of focal and diffuse lung disease: comprehensive diagnosis with reconstruction of contiguous and high-resolution CT sections from a single thin-collimation scan. , 2001, AJR. American journal of roentgenology.

[12]  C A Kelsey,et al.  Use of radiology in U.S. general short-term hospitals: 1980-1990. , 1993, Radiology.