Image sharing – exploring the options
With reference to Erik L. Ridley’s coverage at Aunt Minnie, the experiences from the image-sharing project in Ontario, Canada, can be summarized as follows: setting up large image-sharing networks is highly challenging despite all the existing standards that target this issue.
The article provides a solid overview of the benefits and drawbacks of the two main options for accessing image data in a central repository: ingestion to local PACS in advance or on-the-fly access. Whereas there are many data integrity and security advantages with the on-the-fly approach, the main obstacle is stated to be that in some cases a web-based viewer separate from the local PACS is needed. In my view, radiologists are refusing such a solution with good reason. A true sharing solution provides access to central repository images within the PACS workstation just as easy as the local images. The user should not even have to be aware of where the prior studies originate from.
An option not mentioned (since it is not currently relevant in Ontario) is to achieve the sharing without a central repository. The IHE XDS-I profile allows this, in a setup where merely a registry is central but the images are sent directly from source to destination. The objective of minimizing image transfer is definitely best served in this model, since transfer is only done on a need-to-know basis. This model may, however, be less appealing for regional IT departments due to management complexities – but my feeling is that the benefits often do not get the attention they deserve. The question of ingestion or on-the-fly access remains as valid as in the central model, however, and so do the challenges.
There are many ways to implement image sharing, and what is right for a given organization is probably not right for another. The only thing you can be certain of is that you need vendors that are knowledgeable and flexible enough to help you find and implement the best solution.
