Phantom Files

Phantom Files

Phantoms are used to specify the virtual patient, through simulation of a specific anatomic instantiation. Phantoms can take two general forms: single modality phantoms typically encode modality specific tissue properties, such as attenuation coefficients for radiography or CT, or T1/T2 for MRI; multimodality phantoms typically encode tissue labels, such as skin, muscle, bone, etc. so that properties needed to simulate the phantom can be assigned at the time of the simulation.

Phantoms must also encode the spatial extend of the various tissues. A number of encoding schemes are possible, including voxel arrays, octrees, nurbs, segmented volumes, etc.

OpenVCT phantoms include an XML header containing metadata relevant to the creation and use of the phantom, together with the digital tissue data. The exact form of the file depends upon the phantom encoding scheme.

[Andrew Maidment]

As we move forward with this effort, we would like to develop a DICOM standard for encoding anatomic models.