Intelligent DICOM Prefetch
Radiologists need prior studies available during the exam — not after. But built-in prefetch on most workstations doesn't retrieve priors until the patient is already positioned, pulls everything indiscriminately, and can't coordinate across archives.
DICOM Capacitor monitors the worklist, triggers prefetch hours or days before the exam, filters by relevance, converts formats inline, and stages priors so they're ready when the patient arrives.
The Problem with Traditional Prefetch
Most prefetch solutions — whether built into acquisition workstations or offered as standalone routers — share the same fundamental limitations:
Timing
- Prefetch triggers only at study commencement — patient already positioned
- Technologists must wait for prior transfers to complete
- On slow or congested networks, this delay makes prefetch impractical
Filtering
- All prior studies are retrieved, regardless of relevance
- Non-mammography images (chest X-rays, ultrasounds) are unnecessarily transferred
- Network bandwidth and local storage consumed by irrelevant data
- Large transfers further increase waiting time
Vendor Lock-In
- Many prefetch solutions are tied to a single vendor's ecosystem
- Limited to specific PACS or workstation platforms
- No format conversion — proprietary images stay proprietary
- Upgrading or migrating means re-implementing prefetch from scratch
The result: technologists either wait too long or skip priors entirely.
How Capacitor Solves It
Worklist-Based Early Trigger
The key innovation is automated prefetch initiation based on the worklist, not study commencement:
- Capacitor monitors the DICOM Worklist for upcoming appointments
- When new appointments appear, it automatically initiates prefetch
- Starts the process hours or days before the exam
- Transfers scheduled during off-peak hours (typically overnight)
- Prior images are ready before the patient arrives
- Zero workflow delay for technologists
Smart Filtering
Capacitor dynamically filters studies based on configurable rules:
- Modality — only mammography images, not chest X-rays
- Study age — e.g., last 5 years only
- Body part — relevant anatomy only
- Protocol — specific exam types
- Any DICOM attribute — fully configurable filter expressions
This dramatically reduces unnecessary data transfer, preserves network bandwidth, and prevents local storage overflow.
Multi-Source Coordination
Many facilities store older studies in long-term archives, requiring multi-step retrieval:
- Find archived studies that need to be retrieved
- Move studies from archive to main PACS (often overnight)
- Transfer from PACS to the workstation
- Verify everything is staged and ready
Capacitor manages this entire chain:
- Coordinates across archive, PACS, and workstation
- Tracks when studies arrive at each stage
- Handles VNAs, tiered storage, and multiple PACS systems
- Ensures all priors are ready when needed
Format Conversion on Prefetch
Prior studies from external sources or legacy archives often arrive in proprietary formats. Capacitor converts inline during prefetch:
- SCO → BTO — Hologic proprietary tomosynthesis format to DICOM standard
- CTO → BTO — Siemens legacy single-frame tomosynthesis to standard multi-frame
- DICOM tag harmonization — corrects metadata inconsistencies across PACS sources
- Compression — JPEG 2000 to optimize storage and transfer
Radiologists see standard BTO regardless of the original format. No manual intervention, no broken displays.
Traditional Prefetch vs. Capacitor
| Capability | Traditional Prefetch | Capacitor Prefetch |
|---|---|---|
| Trigger timing | At study commencement | Hours/days before exam |
| Filtering | None or basic — retrieves everything | By modality, age, body part, protocol, any DICOM attribute |
| Multi-source | Single PACS or vendor-specific | Archive, VNA, multiple PACS — vendor-neutral |
| Format conversion | None | SCO/CTO → BTO inline |
| Scheduling | Immediate only | Off-peak, overnight, or on-demand |
| Network impact | Full bandwidth during clinical hours | Scheduled to avoid congestion |
| Storage management | Fills storage indiscriminately | Filtered — only relevant priors |
| Vendor compatibility | Tied to one ecosystem | Any PACS, any modality, any vendor |
| Optimization | Static configuration | Flux tunes per site over time |
Ongoing Optimization
Flux maintains active partnerships with customers to continuously optimize prefetch:
- Regular consultation — review effectiveness, update filtering rules based on technologist feedback
- Schedule tuning — adjust transfer windows to match facility workflows
- PACS compatibility — proactively test against new PACS versions, update protocols as needed
- Network optimization — fine-tune bandwidth utilization parameters
- Site-specific customization — each deployment is tailored to local workflow, storage, and network constraints
Prefetch configuration is not a one-time setup — Flux engineers remain available to adjust as needs evolve.
For configuration details on prefetch triggers, filter expressions, scheduling windows, and multi-source coordination, see the DICOM Capacitor documentation.
Get Started
Whether you need prefetch for mammography, CT, or multi-modality workflows — Capacitor retrieves the right priors, at the right time, in the right format.