Digital Imaging and Communications in Medicine (DICOM)

6.2 Image Compression 95
instead of checkers, this led to visible blurring of the image. The R comp for both
images was about 70. Compressing them to one-tenth of the original size would
have produced a much better result, visually identical to the original image.
Bear in mind that responsibility for using lossy compression rests on the
radiologist’s shoulders; and the radiologist will be to blame if something is misinterpreted
due to image quality loss. PACS manufacturers are only responsible
for:
1. Consistently providing noncompressed images and providing compression as
an option. Using the lossy option is your choice.
2: Clearly labeling lossy-compressed images as such when they are displayed on
the viewing workstation. In this case, if you are not satisfied with the image
quality, you should be able to reload the images as uncompressed (always
confirm this with your PACS vendor).
Furthermore, repetitive application of lossy compression can severely degrade
image quality. If you passed the original CT image through a single lossy compress-uncompress
cycle using a reasonable compression ratio (for example,
R comp