While not as widely known as the terms internet or website, blockchain is a word that’s hit the public lexicon in recent years, even though it was first described in an article in 1991. It’s best-known as the technology driving cryptocurrencies, but there’s so much more potential.

At its very basic level, blockchain is made up of two parts — the block, which is a set of information about a transaction, and the “chain”, which is created by adding a tiny summary of the previous block (hash) from the previous block to the current block.

According to Eliot Siegel, professor and vice chair at the University of Maryland School of Medicine, Department of Diagnostic Radiology, as well as chief of Radiology and Nuclear Medicine for the Veterans Affairs Maryland Healthcare System, and a well-respected source for PACS and other healthcare tech topics, the power of blockchain lies in the fact that it represents an alternative database that is distributed rather than centralized.

The decentralization rather than being a security risk, is instead, a benefit. It’s redundancy by design. Which means if something were to happen to one repository for that information, the data is still safe, since it’s also in multiple other locations. The other benefit is that the data is essentially non-corruptible due to that dispersion and how the blockchain is structured. “There’s information appended to each of the blocks that’s dependent on the block before it. If one were to change the data, it would require access to multiple instances in different locations as well as modification to multiple other blocks in those locations dependent on the block that was altered. Any time you change the data in one block, it propagates to all subsequent blocks, making it clear that a modification has been made,” Siegel says.

Blockchain for healthcare has less to do with digital currency and more to do with industry-specific information. According to Siegel, a top-of-mind application for blockchain would be the sharing of medical imaging. Current state-of-the-art sharing of imaging has a lot of inherent problems. CDs are probably the best/worst example. “CDs can be lost, are typically inherently unsecure, often do not conform to the IHE standard, and are often not encrypted. There may be unfamiliar software on the CD to view the images that the recipient may not be able to use or understand. And a lot of users are locked out of administrative access to their computers, so they can’t install the software that’s been imbedded on the CDs,” says Siegel. “An alternative would be for patients to have true ownership of their data in such a way that they would be able to have a trail or distributed ledger — which would be the terminology for blockchain — of any access to their images and be able to control who has access and who doesn’t, without there necessarily being a priori agreements between any two specific entities that need to share and access the images.”

With a decentralized system, controlled by the patient and/or providers, sharing could be simplified and streamlined, while keeping control in the patient or provider’s hands, whether it’s an exchange of EHR text information, or imaging, or any other relevant information. A peer-to-peer transaction would create this improved flow of the data with greater patient control.

Siegel says in addition to EHR information and medical imaging, blockchain could be used for things such as pre-authorization, asset ownership, the credentialing process, voting within medical societies and even sharing of data for machine learning purposes. The best way for this to work is to have multiple entities contributing to the robustness of the data and that future may be right around the corner.

“As time goes on, more and more people seem to be convinced that blockchain will be an emergent technology representing a market in the tens of billions of dollars as a better mechanism to be able to safeguard and secure data,” he says.

Before this can happen, Siegel says there will need to be significant reengineering done to existing imaging and other information systems in order to allow them to support a blockchain mechanism. There’s also the issue of selecting which blockchain to go with to allow highest efficiency and greatest control by patients, safety, and security.

At this moment, healthcare is very early in its implementation of blockchain, with no definitive map forward on a large scale. A literature search for blockchain in radiology or medical imaging will currently return very little. So there is still extensive work needed to be able to address existing protocols that enable image sharing, such as the IHE cross document sharing for imaging protocol.

It’s already been explained how patients could win if the technology enables them to control their own records better. Providers could win via decreased costs, as inefficiencies decrease as silos of data are better-exchanged. On the opposite side of that coin are third-parties that provide centralized solutions, particularly companies that use centralized solutions to give patients access to their data.

The other winner would be the company providing the mechanism for decentralized transactions. “That might be a company that specializes in healthcare blockchain, or medical imaging or transactional blockchain. Then, each one of the systems would essentially utilize that software as a service to exchange and access the images and other healthcare data,” Siegel explains.

A familiar explanation of how that would work is to think of Napster, the music peer-to-peer exchange of the aughts. The data wasn’t stored with Napster, Napster instead provided the software as a service to create a portal to facilitate that peer-to-peer sharing of information between users. Ideally, healthcare could utilize blockchain technologies to allow this peer to peer sharing, hopefully minus the extensive lawsuits.