Radiology Service — Sync Contract

Status: populated Owner: TBD Last updated: 2026-04-18 Companion: Service Template · 03 platform-services · 02 DDD

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1. Per-Aggregate Conflict Policy

Aggregate / Entity	Conflict policy	Rationale
ImagingStudyRef	server_authoritative	PACS is the system-of-record; EHR metadata reflects PACS state
RadiologyReport (preliminary)	server_authoritative	Only one radiologist owns a report draft at a time
RadiologyReport (final)	append_only	Final reports are immutable; amendments create new versions
PacsEndpoint	server_authoritative	Admin-only config; no offline mutations expected

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2. Offline Behavior

Radiology service is primarily hub-deployed; facility-node deployment is minimal (metadata only). When hub is unreachable:

• Study registration can be deferred; outbox accumulates.
• Viewer launch is blocked (requires PACS connectivity and valid ABAC check).
• Report ingestion via direct API is blocked; via HL7 v2 / interop-service may succeed if interop-service runs locally.

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3. PACS Metadata Freshness

Study metadata (series count, instance count) is updated via QIDO-RS polling or webhook. Staleness policy: metadata older than 24 hours triggers a re-sync on next access.

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4. Optimistic Locking

All mutable rows include a version column enforced on updates:

UPDATE radiology_reports
SET status = $status, version = version + 1
WHERE id = $id AND version = $expectedVersion;

Zero rows updated → 409 CONFLICT.