Detailed Information

Effects of spatial resolution and tube current on computer-aided detection of polyps on CT colonographic images: phantom study

DC Field Value Language
dc.contributor.authorKim, Se Hyung-
dc.contributor.authorLee, Jeong Min-
dc.contributor.authorShin, Cheong-Il-
dc.contributor.authorKim, Hyo Chul-
dc.contributor.authorLee, Joon-Goo-
dc.contributor.authorKim, Jong Hyo-
dc.contributor.authorChoi, Jin Young-
dc.contributor.authorEun, Hyo Won-
dc.contributor.authorHan, Joon Koo-
dc.contributor.authorLee, Jae Young-
dc.contributor.authorChoi, Byung Ihn-
dc.identifier.citationRadiology. 2008;248(2):492-503en
dc.identifier.issn1527-1315 (Electronic)-
dc.identifier.issn0033-8419 (Print)-
dc.description.abstractPURPOSE: To prospectively evaluate the effects of z-axis spatial resolution and tube current on the sensitivity of a commercially available computed tomographic (CT) colonography computer-aided diagnosis (CAD) system for polyp detection by using pig colon phantoms. MATERIALS AND METHODS: Ninety-six polyps were created and analyzed in 14 pig colon phantoms. CT colonography was performed by using a 16-detector CT scanner at 0.75-mm collimation; 10, 50, 100, and 160 mAs; and a pitch of 1.5. At each milliampere-second setting, the CT images were reconstructed with a section thickness (ST) of 1.5 mm and a reconstruction increment (RI) of 1.3 mm. To evaluate the effect of z-axis spatial resolution, CT images were also reconstructed at 100 mAs with various SI and RI combinations (respectively: 1.0 and 0.7 mm, 3.0 and 2.0 mm, 3.0 and 3.0 mm, 5.0 and 5.0 mm). The phantom data were then analyzed by using a CAD program. CAD performance with different CT parameters was calculated and compared in terms of per-polyp sensitivity and number of false-positive (FP) findings per data set. RESULTS: At a constant tube current of 100 mAs, the polyp detection rate was significantly higher in data sets obtained with SI and RI combinations of 1.0 and 0.7 mm, respectively (81% [78/96]), and 1.5 and 1.3 mm, respectively (75% [72/96]), than in those obtained with the three thicker ST-RI settings (27% [26/96] to 64% [61/96]) (P < .01). A similar trend was observed, regardless of polyp size or morphology. However, the number of FP findings at the 1.0 mm and 0.7 mm setting (8.9 per phantom) was also significantly greater than that at the thicker ST-RI settings (4.0-6.1 per phantom) (P < .05). At a constant z-axis spatial resolution (1.5-mm ST, 1.3-mm RI), CAD polyp detection rate and number of FP findings per phantom remained nearly constant-close to 78% (75/96) and 6.1, respectively-at various tube current settings. CONCLUSION: CAD performance in polyp detection at CT colonography is highly dependent on z-axis spatial resolution. However, tube current is not an influencing factor in CAD performance at a given z-axis spatial resolution. Supplemental material:
dc.publisherRadiological Society of North America (RSNA)en
dc.subjectColonic Polyps/*radiographyen
dc.subjectFalse Positive Reactionsen
dc.subjectProspective Studiesen
dc.subjectSensitivity and Specificityen
dc.subjectColonography, Computed Tomographic-
dc.subjectPhantoms, Imaging-
dc.subjectRadiographic Image Interpretation, Computer-Assisted-
dc.titleEffects of spatial resolution and tube current on computer-aided detection of polyps on CT colonographic images: phantom studyen
Appears in Collections:
Files in This Item:
There are no files associated with this item.


Item View & Download Count

  • mendeley

Items in S-Space are protected by copyright, with all rights reserved, unless otherwise indicated.