This paper presents a study on quantifying and understanding the impact of multiple lossy JPEG compression cycles on medical images. In medical imaging applications, an image is compressed using a specific technique and parameters and then transmitted to a user (i.e., physician) where it is decompressed for viewing. The user may then wish to retransmit the decompressed image (or a portion of the image) to another user for further review. This second transmission might use the same compression parameters as the first transmission, or they might change because of system constraints. This cycle of compression/decompression might be repeated several times. When performing multiple JPEG compression cycles, several scenarios are likely to occur between cycles: (1) changes in the compression ratio; (2) changes in the quantization table; and (3) cropping of the image. In this study, we considered combinations of high (40:1), medium (20:1), and low (10:1) compression ratios and visually-based q-tables designed for viewing distances of 2, 3, and 4-picture heights. The compression ratio and/or q-table were varied between compression cycles. We also consider cropping of the image by one-pixel increments between compression cycles. Root-mean- squared error (RMSE) between the original image and the decompressed image was used to quantify the impact of these parameters. This study examined these issues for the specific case of computed radiography images.