| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Computer Applications |
1 From the Division of Abdominal Imaging and Intervention (M.E.Z., P.F.H., R.S.A., G.S.G., P.R.M.) and the Decision Analysis and Technology Assessment Group (G.S.G.), Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114; and the Department of Health Policy and Management, Harvard School of Public Health, Boston, Mass (G.S.G.). From the 1999 RSNA scientific assembly. Received September 14, 2000; revision requested November 2; final revision received March 1, 2001; accepted March 16. Address correspondence to M.E.Z. (e-mail: mzalis@mindspring.com).
PURPOSE: To assess the consequences of lossy compression on the diagnostic accuracy of CT colonography for detecting colonic polyps.
MATERIALS AND METHODS: Helical CT images of cleansed colonic segments were evaluated. Source images were compressed to 1:1, 10:1, and 20:1 ratios with lossy wavelet compression. Two independent readers blinded to corresponding colonoscopic results analyzed 144 randomly ordered colonic segments in multiplanar and volume-rendered endoscopic views. Sensitivity, specificity, and receiver operating characteristic curves were generated for each compression ratio on the basis of expressed confidence in lesion presence. Similar analyses were performed to assess distention and bowel preparation adequacy and evaluation time required.
RESULTS: Results based on video colonoscopy–confirmed lesions revealed 100% (four of four) sensitivity for lesions larger than 10 mm for compression ratios 1:1, 10:1, and 20:1 for both readers; sensitivities for all lesions smaller than 10 mm were 50%–78%, 38%–67%, and 38%–67% for respective ratios for both readers. Differences in diagnostic performance for each reader across ratios were not significant (P = .30-.99, McNemar test). The time required to evaluate and assess bowel preparation and distention adequacy did not change significantly across ratios.
CONCLUSION: On the basis of the patient sample, lossy compression of transverse source images to at least a 20:1 ratio did not adversely affect diagnostic performance or evaluation time for CT colonography.
Index terms: Colon, abnormalities, 75.311, 75.321 • Colon, CT, 75.12111, 75.12115, 75.12117 • Colonoscopy, 75.1289
This article has been cited by other articles:
|
|
 |
|
  H. Ringl, R. Schernthaner, E. Sala, K. El-Rabadi, M. Weber, W. Schima, C. J. Herold, and A. K. Dixon Lossy 3D JPEG2000 Compression of Abdominal CT Images in Patients with Acute Abdominal Complaints: Effect of Compression Ratio on Diagnostic Confidence and Accuracy Radiology, August 1, 2008; 248(2): 476 - 484. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. Kim, K. H. Lee, K. J. Kim, R. Mantiuk, S. Hahn, T. J. Kim, and Y. H. Kim Prediction of Perceptible Artifacts in JPEG 2000 Compressed Chest CT Images Using Mathematical and Perceptual Quality Metrics Am. J. Roentgenol., February 1, 2008; 190(2): 328 - 334. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Ringl, R. E. Schernthaner, C. Kulinna-Cosentini, M. Weber, C. Schaefer-Prokop, C. J. Herold, and W. Schima Lossy Three-dimensional JPEG2000 Compression of Abdominal CT Images: Assessment of the Visually Lossless Threshold and Effect of Compression Ratio on Image Quality Radiology, November 1, 2007; 245(2): 467 - 474. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. S. Woo, K. J. Kim, T. J. Kim, S. Hahn, B. Kim, Y. H. Kim, and K. H. Lee JPEG 2000 Compression of Abdominal CT: Difference in Tolerance Between Thin- and Thick-Section Images Am. J. Roentgenol., September 1, 2007; 189(3): 535 - 541. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| RADIOLOGY | RADIOGRAPHICS | RSNA JOURNALS ONLINE |
