Chang Ho Jeon MD, Presenter: Nothing to Disclose

Kil Joong Kim, Abstract Co-Author: Nothing to Disclose

Kyoung Ho Lee MD, Abstract Co-Author: Research Grant, General Electric Company

To propose a preprocessing technique that increases the compressibility in reversible compressions of various CT images, and to measure the increase in compression ratio (CR) in Joint Photographic Experts Group (JPEG) 2000 reversible compression.

Our institutional review board approved this study and waived informed patient consent. We developed the preprocessing technique which automatically segments pixels outside the region of diagnostic interest and replaces their values with a constant value to maximize data redundancy. 223 scans (total 181,904 images) obtained with various body parts (abdomen, chest, and brain), scan protocols, and reconstruction parameters (section thickness, field of view) were preprocessed using the technique and then reversibly compressed using the JPEG2000 compression. The CRs with and without the preprocessing technique were compared using paired t tests. The percentage increase in the CR per scan and the percentage volume outside the ROI per scan were calculated. The linear regression coefficient was measured between them.

The CR increased significantly (without vs. with the preprocessing) (3.07 [mean] vs. 4.73, p < .001) for all types of scans. The mean percentage increases in CR with the preprocessing were 54.3% (95% CI, 50.5-57.2%). The mean percentage volumes outside the ROI for all scans were 40.7%. The linear regression coefficient between the percentage increase in CR and the percentage volume outside the ROI were 0.77 (95% CI: 0.73, 0.80; p < .001).

Our preprocessing technique considerably increases CRs for reversible JPEG2000 compression of various CT scans.

Our proposed preprocessing technique increases reversible CRs for the tested CT scans and may allow us saving the system resources required for storage and transmission of CT images.

Jeon, C, Kim, K, Lee, K, Improving Compressibility in JPEG2000 Reversible Compressions of CT Images by Increasing the Data Redundancy outside the Region of Diagnostic Interest.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12032168.html