Blockchain technology had its beginnings in the financial sector and is most commonly associated with cryptocurrencies, but it is also beginning to emerge as a significant player in the healthcare industry. A recent study published in the Journal of Digital Imaging explored the history of blockchain and examined its potential impact on the future of medical imaging technology.
“Specifically within medical imaging, blockchain use cases include image sharing (including patient-driven/centered ownership of images), teleradiology, research, and machine learning/artificial intelligence applications,” wrote authors Morgan P. McBee, MD, Medical University of South Carolina, and Chad Wilcox, MD, University of California Los Angeles. “It is more practical to store hashes, metadata or references/links to images within the blockchain as opposed to images themselves as illustrated in one proposed blockchain implementation for sharing of images. This is especially true because of the slow speed and high cost of storing large amounts of data in a public blockchain.”
There are, however, four key limitations McBee and Wilcox discussed in their assessment. Any researchers looking to learn more about blockchain should keep these limitations in mind at all times.
The four limitations are:
“With an ever increasing number of blockchain implementations utilizing different underlying technologies, the ability of different systems to work together will suffer,” the authors wrote, noting that “unforeseen complications” seem likely when contracts interact with no human interaction involved.
Blockchain technology will soon need a DICOM-like standard to avoid this issue from continuing to get worse as time goes on.
If the encryption associated with any given blockchain is ever broken, McBee and Wilcox explained, the data stored in that blockchain would be vulnerable to would-be attackers. This isn’t such an issue with the technology available today, the authors added, but there will be a point in the future where such an issue is possible.
Blockchain requires much more computational power and electricity than a traditional database, leading to slower speeds and higher costs.
“One method to reduce the transaction costs is to only allow certain nodes to participate in consensus; however, some redundancy is lost by doing so,” the authors wrote.
When a private key is lost or forgotten, the blockchain’s data quickly becomes “permanently unreadable,” McBee and Wilcox explained. More research is needed to explore this issue further and hopefully develop improved ways for users to never lose of forget their key.
“Additionally, blockchains are at risk of what is known as a ‘51% attack,’” the authors added. “If an attacker were to take control of 51% or more of the nodes comprising the blockchain network, the consensus mechanism could be overridden allowing for double spending.”