The use of watermarking in medical records as a method of accurate identification is immediately apparent. With the medical industry migrating more and more toward digital records, watermarking becomes a mandatory addition to prevent mix-ups in patient records. Because of the various protocols and different platforms used in the computer world, data sometimes can become corrupted when it is converted from one format to another. Presently, most image formats separate the image data from the text; an x-ray is separate from the name of the patient, the date of the x-ray, and the name of the physician; if the link between the image and the text were ever broken, things could get bad in a hurry. A way to prevent this is to embed into the image the patient's name and all other pertinent information.
Every patient has an EPR (electronic patient record) made up of examinations, diagnoses, prescriptions, etc., basically a master file containing the record of what has been done with respect to the patient. Using this as an obvious vehicle, a watermarking scheme could be used very effectively.
Watermarking in the medical arena has three main objectives:
Hiding metadata, information about the information, to make the image easier to use
Integrity control, meaning the image has not been inappropriately modified
Authenticity — the image is what the user thinks it is
Authentication and tracing: Because medical images pass through a number of hands and go through a variety of processes, the introduction of a digital watermark serves as a guarantee that no errors, accidental or otherwise, have been introduced into the image.
EPR diffusion: If the patient maintains control of his or her own medical record, watermarking is also useful when distributing the record to various sites. Because this record is digital, multiple copies can exist at once; watermarking ensures that the newest is being used and has not been tampered with.