Authentication of digital medical images with digital signature technology.
OBJECTIVE
To determine whether digital signature technology (DST) can authenticate digital medical images to the same level of authenticity required for interbank electronic transfer of funds.


METHODS
Message digests were computed for two magnetic resonance images that differed only by the value of a single bit. RSA (Rivest, Shamir, and Adleman) public key cryptography was used to encrypt each message digest to form a digital signature for each image, a process analogous to the established use of RSA DST for electronic funds transfer. The process was then reversed to authenticate the original image from its digital signature.


RESULTS
Although the images differed by less than 0.000095%, their message digests differed at 94% of their characters. The digital signature of the original image proved that it was authentic and that the altered image was not authentic.


CONCLUSIONS
RSA DST can establish the authenticity of images to at least the level of confidence required for interbank electronic transfer of funds.
Smith
J P
JP
First Hill Diagnostic Imaging, Seattle, WA 98104.
D000465:Algorithms; D016494:Computer Security; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D011873:Radiology Information Systems