HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by McFarland, E. G. Articles by Littenberg, B. Search for Related Content PubMed PubMed Citation Articles by McFarland, E. G. Articles by Littenberg, B.

CT Colonography: Multiobserver Diagnostic Performance¹

¹ From the Mallinckrodt Institute of Radiology (E.G.M., T.K.P., R.A.M., C.V.S., P.W.B., J.P.H., D.M.B.) and Department of Internal Medicine, Gastroenterology Division (L.B.W., E.P.T.), Washington University School of Medicine, 510 S Kingshighway Blvd, St Louis, MO 63110; Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Conn (J.A.B.); and Department of General Internal Medicine, University of Vermont, Burlington (B.L.). Received October 2, 2001; revision requested November 16; final revision received June 6, 2002; accepted June 7. Supported in part by National Cancer Institute PLCO Cancer Screening Trial (N01-CN-25516), General Electric, Association of University Radiologists (GERRAF, EGM), and Washington University Siteman Cancer Center. Address correspondence to E.G.M. (e-mail: mcfarlandb@mir.wustl.edu).

View larger version (103K): [in a new window]   Figure 1a. CT images depict an 8-mm polyp (arrow) in a well-distended region of sigmoid colon, which was identified by the majority of readers. (a) Transverse 2D MPR depicts the polyp. (b) Two-dimensional coronal MPR also demonstrates focality of lesion, best represented with cine motion (not shown). (c) Three-dimensional PVR endoscopic image increased confidence in several readers with regard to the presence of a lesion.

View larger version (81K): [in a new window]   Figure 1b. CT images depict an 8-mm polyp (arrow) in a well-distended region of sigmoid colon, which was identified by the majority of readers. (a) Transverse 2D MPR depicts the polyp. (b) Two-dimensional coronal MPR also demonstrates focality of lesion, best represented with cine motion (not shown). (c) Three-dimensional PVR endoscopic image increased confidence in several readers with regard to the presence of a lesion.

View larger version (149K): [in a new window]   Figure 1c. CT images depict an 8-mm polyp (arrow) in a well-distended region of sigmoid colon, which was identified by the majority of readers. (a) Transverse 2D MPR depicts the polyp. (b) Two-dimensional coronal MPR also demonstrates focality of lesion, best represented with cine motion (not shown). (c) Three-dimensional PVR endoscopic image increased confidence in several readers with regard to the presence of a lesion.

View larger version (95K): [in a new window]   Figure 2a. CT images depict an 8-mm polyp (arrow) at the base of a fold in the hepatic flexure (seen only on the prone images), which was missed by the majority of readers. (a) Transverse 2D MPR shows raised area on a fold, which is difficult to discriminate from a nodular fold. (b) Three-dimensional PVR endoscopic image better demonstrates focal nature of the lesion.

View larger version (125K): [in a new window]   Figure 2b. CT images depict an 8-mm polyp (arrow) at the base of a fold in the hepatic flexure (seen only on the prone images), which was missed by the majority of readers. (a) Transverse 2D MPR shows raised area on a fold, which is difficult to discriminate from a nodular fold. (b) Three-dimensional PVR endoscopic image better demonstrates focal nature of the lesion.

View larger version (125K): [in a new window]   Figure 3a. Images of a large 23-mm sessile lesion (arrows) near the hepatic flexure, which was correctly classified as a polyp by only one reader. (a) Transverse 2D MPR reveals only a portion of the lesion. (b) Sagittal 2D MPR demonstrates a broad region of abnormality along the fold. (c) Three-dimensional PVR endoscopic image better represents the overall morphology and length of the lesion. (d) Corresponding fiberoptic colonoscopic image correlates well with c.

View larger version (115K): [in a new window]   Figure 3b. Images of a large 23-mm sessile lesion (arrows) near the hepatic flexure, which was correctly classified as a polyp by only one reader. (a) Transverse 2D MPR reveals only a portion of the lesion. (b) Sagittal 2D MPR demonstrates a broad region of abnormality along the fold. (c) Three-dimensional PVR endoscopic image better represents the overall morphology and length of the lesion. (d) Corresponding fiberoptic colonoscopic image correlates well with c.

View larger version (115K): [in a new window]   Figure 3c. Images of a large 23-mm sessile lesion (arrows) near the hepatic flexure, which was correctly classified as a polyp by only one reader. (a) Transverse 2D MPR reveals only a portion of the lesion. (b) Sagittal 2D MPR demonstrates a broad region of abnormality along the fold. (c) Three-dimensional PVR endoscopic image better represents the overall morphology and length of the lesion. (d) Corresponding fiberoptic colonoscopic image correlates well with c.

View larger version (138K): [in a new window]   Figure 3d. Images of a large 23-mm sessile lesion (arrows) near the hepatic flexure, which was correctly classified as a polyp by only one reader. (a) Transverse 2D MPR reveals only a portion of the lesion. (b) Sagittal 2D MPR demonstrates a broad region of abnormality along the fold. (c) Three-dimensional PVR endoscopic image better represents the overall morphology and length of the lesion. (d) Corresponding fiberoptic colonoscopic image correlates well with c.

View larger version (91K): [in a new window]   Figure 4a. Large 18-mm false-positive finding is shown in the sigmoid colon, which was incorrectly classified as a polyp by all four readers. (a) Transverse 2D MPR (in supine position) demonstrates the focal finding (arrowhead). (b) Transverse 2D MPR (in prone position) demonstrates a slight shift in the position of the lesion (arrowheads) to the dependent anterior wall. (c) Sagittal 2D MPR (in prone position) also demonstrates the focal finding (arrowhead). (d) Three-dimensional PVR endoscopic image demonstrates less focal morphology (arrows) of this region.

View larger version (89K): [in a new window]   Figure 4b. Large 18-mm false-positive finding is shown in the sigmoid colon, which was incorrectly classified as a polyp by all four readers. (a) Transverse 2D MPR (in supine position) demonstrates the focal finding (arrowhead). (b) Transverse 2D MPR (in prone position) demonstrates a slight shift in the position of the lesion (arrowheads) to the dependent anterior wall. (c) Sagittal 2D MPR (in prone position) also demonstrates the focal finding (arrowhead). (d) Three-dimensional PVR endoscopic image demonstrates less focal morphology (arrows) of this region.

View larger version (123K): [in a new window]   Figure 4c. Large 18-mm false-positive finding is shown in the sigmoid colon, which was incorrectly classified as a polyp by all four readers. (a) Transverse 2D MPR (in supine position) demonstrates the focal finding (arrowhead). (b) Transverse 2D MPR (in prone position) demonstrates a slight shift in the position of the lesion (arrowheads) to the dependent anterior wall. (c) Sagittal 2D MPR (in prone position) also demonstrates the focal finding (arrowhead). (d) Three-dimensional PVR endoscopic image demonstrates less focal morphology (arrows) of this region.

View larger version (143K): [in a new window]   Figure 4d. Large 18-mm false-positive finding is shown in the sigmoid colon, which was incorrectly classified as a polyp by all four readers. (a) Transverse 2D MPR (in supine position) demonstrates the focal finding (arrowhead). (b) Transverse 2D MPR (in prone position) demonstrates a slight shift in the position of the lesion (arrowheads) to the dependent anterior wall. (c) Sagittal 2D MPR (in prone position) also demonstrates the focal finding (arrowhead). (d) Three-dimensional PVR endoscopic image demonstrates less focal morphology (arrows) of this region.

View larger version (37K): [in a new window]   Figure 5. Graph shows sensitivity calculated at different lower limits of polyp size for individual polyps (dotted lines) and patients, categorized by their largest polyp (solid lines). For each tested lower limit of polyp size, only polyps (or patients) equal to or larger than the threshold are evaluated. Each line with symbols represents results for individual readers. Each symbol represents one of the four readers.

View larger version (34K): [in a new window]   Figure 6. Results of the area under the receiver operating characteristic curve (for patients) calculated at different thresholds of polyp size. For each tested lower limit of polyp size, all 70 patients are included. Convergence of reader curves occurs at a threshold of approximately 10 mm. Each line with symbols represents results for individual readers. Each symbol represents one of the four readers.