IMPAX 6.5.1 Client Knowledge Base: Extended > Administering IMPAX > Defining study text and priors > Defining relevancy rules for opening priors
What is prefetching?
Prefetching is the automatic retrieval of relevant priors based on information transmitted from the RIS. Two types of events can trigger a prefetching event and both are generated from the RIS: a scheduled exam and a scheduled visit. If an exam is scheduled at the RIS, the prefetching rules are triggered; in the event of a scheduled visit, the referring location prior rules are invoked. In both cases, IMPAX searches for studies that match the defined rules and retrieves them from archives (if needed).
What are relevancy rules?
Relevancy rules determine which studies are considered the most important priors for comparison to the current study being interpreted. Relevancy rules can be created for a user, role, or department. However, you must remember that the scope of every relevancy rule defined must be smaller than the scope of its related prefetching rule.
Ensure you check the site's relevancy rules periodically and compare each one against their corresponding prefetching rules. If a discrepancy exists in any of the parameters (such as five studies vs. three studies or all images vs. key images), ensure the relevancy rules are a subset of what the prefetching rules define. Failing to do so causes IMPAX to trigger many retrieval jobs during the day, thus affecting its performance negatively.
Example
A prefetching rule is defined for Head CT studies, indicating that the site wants the following:
To retrieve up to five priors for the same modality and specialty within the last five years
The entire study (not just the key images)
A similar Relevancy rule is defined in the IMPAX Client; however, it calls for up to 10 priors, with the rest of the parameters matching the prefetching rules. When the radiologist opens a Head CT study with the Relevancy button enabled, IMPAX Client attempts to open those 10 priors. If only five priors are readily available, IMPAX must retrieve the remaining five which can negatively affect the performance of the IMPAX Client.
Topic number: 109864 Applies to: IMPAX 6.5.1 Client Knowledge Base |