Length limit of Detector ID Status Assigned Date of Last Update 2025/01/21 Person Assigned David Clunie Submitter Name Andrew Chaffer Submission Date 2025/01/14 Correction Number CP-2506 Log Summary: Length limit of Detector ID Name of Standard PS3.3, PS3.6 Rationale for Correction: Detector ID (0018,700A) gives a unique serial number for each detector. This is useful as it allows the detector a clinical image has been taken on to be uniquely identified which can be very useful if there are issues such as artefacts. Detector ID (0018,700A) is a short string, which is 16 characters in length, and is too short for the serial numbers of some detectors. For some use cases (such as multi-energy CT) the problem has been solved by the UC VR X-Ray Detector ID (0018,9371). Propagate the use of the longer attribute to all uses of the shorter attribute, allowing for mandatory uses of the shorter attribute. Note that identification of the detector is distinct from identification of the entire equipment/device (so Device Serial Number (0018,1000), an LO VR data element, is not applicable). [Ed.Note. We could retire the use of Detector ID (0018,700A) but since it is used as Type 1 in the Breast Tomosynthesis Contributing Sources Module, this would theoretically be a breaking change.] [Ed.Note. Is it worth harmonizing the description of the two Attributes, e.g., make both "The identifier or serial number of the physical X-Ray detector used to acquire this image"?] [Ed.Note. Are we pushing the generalization here by re-using an X-Ray CT detector ID for general X-Ray purposes, given that one is a flat panel and the other is an assembly of multiple discrete detectors presumably identified as a group?] [Ed.Note. What about trying to re-use UDI at the detector level - probably not.] Correction Wording:

Digital X-Ray Detector Macro Attributes

Attribute Name	Tag	Type	Attribute Description
...
Detector ID	(0018,700A)	3	The ID or serial number of the detector used to acquire this image. Due to the length limit imposed by the VR of this Attribute, a full length serial number may need to be truncated. If truncated, to the extent possible the remaining string value should be as unique as possible within the local (site) context of use, and hence perhaps be the tail rather than the head of the truncated string. The full length value can be encoded in X-Ray Detector ID (0018,9371).
X-Ray Detector ID	(0018,9371)	3	Identifier of the physical X-Ray detector. This might be the serial number. If the value in Detector ID (0018,70)A) is truncated due to VR length limitations, this Attribute may be used to convey the full length value.
Date of Last Detector Calibration	(0018,700C)	3	The date on which the detector used to acquire this image as identified in Detector ID (0018,700A) was last calibrated.
Time of Last Detector Calibration	(0018,700E)	3	The time at which the detector used to acquire this image as identified in Detector ID (0018,700A) was last calibrated.
Exposures on Detector Since Last Calibration	(0018,7010)	3	Total number of X-Ray exposures that have been made on the detector used to acquire this image as identified in Detector ID (0018,700A) since it was calibrated.
Exposures on Detector Since Manufactured	(0018,7011)	3	Total number of X-Ray exposures that have been made on the detector used to acquire this image as identified in Detector ID (0018,700A) since it was manufactured.
...

Breast Tomosynthesis Contributing Sources Module Attributes

Attribute Name	Tag	Type	Attribute Description
Contributing Sources Sequence	(0018,9506)	1	A Sequence that describes characteristics of the sources that are used to create a derived SOP Instance. One or more Items shall be included in this Sequence.
...
>Detector ID	(0018,700A)	1	The ID or serial number of the detector used to acquire this image. Due to the length limit imposed by the VR of this Attribute, a full length serial number may need to be truncated. If truncated, to the extent possible the remaining string value should be as unique as possible within the local (site) context of use, and hence perhaps be the tail rather than the head of the truncated string. The full length value can be encoded in X-Ray Detector ID (0018,9371).
>X-Ray Detector ID	(0018,9371)	3	Identifier of the physical X-Ray detector. This might be the serial number. If the value in Detector ID (0018,70)A) is truncated due to VR length limitations, this Attribute may be used to convey the full length value.
>Date of Last Detector Calibration	(0018,700C)	1	The date on which the detector used to acquire this image as identified in Detector ID (0018,700A) was last calibrated.
>Time of Last Detector Calibration	(0018,700E)	1	The time at which the detector used to acquire this image as identified in Detector ID (0018,700A) was last calibrated.
...

For reference unchanged DICOM PS3.3:

Multi-energy CT X-Ray Detector Macro Attributes

Attribute Name	Tag	Type	Attribute Description
Multi-energy CT X-Ray Detector Sequence	(0018,936F)	1	...
...
>X-Ray Detector ID	(0018,9371)	1	Identifier of the physical X-Ray detector. This might be the serial number. When a single detector discriminates different energies, the X-Ray Detector ID (0018,9371) will have the same value in different Items of Multi-energy CT X-Ray Detector Sequence (0018,936F).
...

For reference unchanged DICOM PS3.6:

Registry of DICOM Data Elements

Tag	Name	Keyword	VR	VM
(0018,700A)	Detector ID	Detector​ID	SH	1
(0018,9371)	X-Ray Detector ID	XRay​Detector​ID	UC	1