The DICOS specification includes parameters for pixel spacing in MM and slice thickness. These parameters, point spacing and slice thickness, are the physical distances between the center of each pixel inthe three coordinate directions. Thus they correspond to pixel size.
In the User-Level API, these parameters are stored in the SectionCommon class. For the IODs that store 3D data, CT and AIT3D, the Section and SectionAIT classes that store CT and AIT3D specific data respectively derive from SectionCommon.
Curiously, the DICOS spec does not define an attribute for setting the pixel spacing for 2D IODs DX and AIT2D.
This has been addressed by updating the DICOS specification to include Table 93 "Basic Pixel Spacing Calibration Macro" in Table 30 "DX IOD Modules".