Usefulness of newly developed interactive multiplanar reconstruction viewer for large amount of image sets by multidetector-row CT: evaluation of invasion to surrounding organs of esophageal carcinoma

摘要

The objective of this study is to evaluate usefulness of newly developed interactive multiplanar reconstruction (MPR) viewer for the evaluation of invasion to surrounding organs of esophageal carcinoma. In 49 sites of these 30 patients who were performed surgical operation, invasion to surrounding organs were histologically confirmed (invasion(+); n=18, invasion(-) n= 31). Before operation, postcontrast helical CT was done with 5-mm slice thickness, 2.5-mm X 4 beam collimation, 6:1 pitch, 120kVp, 200mA/rotation, 0.8 second/gantry rotation, and standard algorithm covering whole esophagus using a multi detector-row CT scanner (LightSpeed QXi, GE, Milwaukee, Wi). The volume data for MPR views were reconstructed from above helical CT data with 2.5-mm slice thickness, 1.25-mm reconstruction intervals, and transferred to a newly developed interactive MPR viewer (KaledoScope, KGT, Tokyo, Japan). This MPR viewer can automatically reconstructs coronal and sagittal MPR views immediately after the transfer of volume data. With drawing lines by a pointing device on axial, coronal, and sagittal basic images, observers can promptly make various MPR views which are at right angles to the lines as they like. Using ROC analysis, an observer performance study, in which three observers indicated the confidence level for the determination of invasion or not for each site by axial 5-mm slice thickness postcontrast CT and interactive MPR views, was done.