General
(0008,0018)
SOP Instance UID
Keyword: SOPInstanceUID
Globally unique identifier for a single DICOM object (one file). Must never be reused across all time and all equipment.
Tag Attributes
- Tag ID
- (0008,0018)
- Compact
- 00080018
- Keyword
- SOPInstanceUID
- VR
- UI — Unique Identifier
- VM
- 1
- Retired
- No
Module(s)
SOP Common Module
Engineering Notes
The primary key of a DICOM object. Generated by the modality using a UID root registered with your organisation. Duplicates cause archival overwrites and retrieval failures.
Troubleshooting
Duplicate SOP Instance UIDs are a common cause of missing studies in PACS. Ensure modality UID roots are unique per site. Reset UID generation after factory resets or cloning of modality config.