Photoacoustic Images are produced from the acquisition of tissue response to one or more Excitation Wavelength (0018,9826) values. These attributes are identified using the Excitation Wavelength Sequence (0018,9825) Dimension Index to capture differences in wavelength absorption by various biological tissues. The property represented by the tissue response is identified by the Image Data Type Sequence (0018,9807) Dimension Index.

Photoacoustic Images are acquired with a volume-based Frame of Reference recorded by the Dimension Index of Image Position (Volume) (0020,9301). The acquisition device may be mounted on a rigid system (tomographic or microscopic system) or freehand. The image frames may be acquired over time as described by the Dimension Index of Temporal Position Time Offset (0020,930D).

Photoacoustic Images may be acquired as a standalone modality or acquired in combination with images from other modalities. Because Photoacoustic and Ultrasound systems are often implemented as coupled modalities, the Photoacoustic Image IOD includes modules and functional group macros similar to those in use in the Section A.59 “Enhanced US Volume IOD” in PS3.3. Any complementary images such as pulse/echo ultrasound are acquired and stored as separate images represented by their native DICOM IODs.

In the case of a Photoacoustic device coupled with another acquisition modality, one acquisition device may know the spatial relationship of its image data relative to the other. One of the acquisition devices may use the Registration SOP Class to specify the relationship of the images from the two modalities. In the most direct case, the data of both modalities are in the same DICOM Frame of Reference for each SOP Class Instance and the Registration object is containing a one-to-one translation.