DICOM PS3.17 2021e - Explanatory Information

TTTT.3 Use Cases

TTTT.3.1 Use Case 1: Linking Dermoscopic Images to A Regional Image

A regional or contextual image is a clinical photograph that includes anatomic reference points (e.g., joint or navel) in the field of view. Dermoscopic images are typically of a single skin lesion (e.g., mole). Linking dermoscopic images to a regional image can give the anatomical location of skin lesion. Further, the linkage may help with the consistent identification of individual skin lesions in sequential dermoscopy.

A regional image may include one or more skin lesions. A skin lesion may be seen in one or more regional images. Therefore, the relationship between the regional image and the linked dermoscopy images is many-to-many.

An example of a regional image shown in Figure TTTT.3-1.

Regional image

Figure TTTT.3-1. Regional image


TTTT.3.1.1 Potential acquisition workflow

The aim of this workflow is to create a link between the regional image(s) and the dermoscopic image(s).

Steps:

  1. A regional image is acquired and displayed on the acquisition modality.

  2. A skin lesion requiring dermoscopy is identified (e.g., by mouse click).

  3. The user is prompted to input a skin lesion label (e.g., Lesion 1) or the acquisition modality actor automatically generates a label. The mouse click generates X and Y co-ordinates to encode in the metadata of the regional image.

  4. A dermoscopy image is acquired and linked to the lesion identified in Step 2.

TTTT.3.1.2 Considerations

  • The skin lesion identifier could be used as the series descriptor for the dermoscopic images of this skin lesion.

  • The metadata of the regional images contains all referenced dermoscopy images (SOP Instance UID) (see Figure TTTT.3-2).

  • The metadata of the dermoscopy image contains referenced regional images (SOP Instance UID) (see Figure TTTT.3-2).

  • The metadata of the regional image contains the X and Y co-ordinate of the lesion (see Figure TTTT.3-2).

  • The metadata of the regional image optionally contains the skin lesion identifier.

  • The dermatology imaging study consists one or more regional images and one or more dermoscopic images.

  • Tracking Identifier (0062,0020) is used to store the skin lesion label.

  • Tracking Unique Identifier (0062,0021) is used to store a vendor generated skin lesion UID.

  • A new regional image for each dermatology imaging study or re-use of the original image from a different imaging study are possible.

Linkage between regional image(s) and dermoscopy image(s) within a dermatology imaging study

Figure TTTT.3-2. Linkage between regional image(s) and dermoscopy image(s) within a dermatology imaging study


TTTT.3.1.3 Potential display functionality

When displaying a dermatology imaging study, a user can click a skin lesion in a regional image, which hyperlinks to display the appropriate dermoscopic image.

Note

  1. The Referenced Image Sequence (0008,1140) may provide a method for relating dermoscopy and regional images.

  2. A DICOM Structured Report object may be used to retrospectively encode the link between skin lesion on a regional image and a dermoscopic image. The use of a DICOM Structured Report object could be extended for longitudinal lesion tracking, see Section TTTT.3.2.

DICOM PS3.17 2021e - Explanatory Information