  Usually, a medical record (MR) contains the patients disease-oriented
sensitive information. In addition, the MR needs to be shared among different
bodies, e.g., diagnostic centres, hospitals, physicians, etc. Hence, retaining
the privacy and integrity of MR is crucial. A blockchain based secure MR
sharing system can manage these aspects properly. This paper proposes a
blockchain based electronic (e-) MR sharing scheme that (i) considers the
medical image and the text as the input, (ii) enriches the data privacy through
a two-fold encryption mechanism consisting of an asymmetric cryptosystem and
the dynamic DNA encoding, (iii) assures data integrity by storing the encrypted
e-MR in the distinct block designated for each user in the blockchain, and (iv)
eventually, enables authorized entities to regain the e-MR through decryption.
Preliminary evaluations, analyses, comparisons with state-of-the-art works,
etc., imply the efficacy of the proposed scheme.
