RT_Image is an application developed in the Department of Radiation Oncology and MIPS at Stanford University. Coded in the Interactive Data Language (IDL, ITT Visual Information Solutions), RT_Image was originally designed in 2003 to generate radiotherapy target volumes from positron emission tomography (PET) datasets. It has since evolved to embody a variety of tools for visualizing, quantitating, and segmenting three-dimensional images.

Multiple datasets may be loaded, displayed, fused, processed, and quantitatively analyzed simultaneously. Data may be imported from any DICOM-compatible three dimensional imaging modality. Regions-of-interest, defined as slabs of arbitrary cross section and fixed thickness, may be defined using a number of manual, semi-automatic, and automated tools to segment three-dimensional pixel volumes. They may also be imported from and exported to DICOM structure sets.

This software has been applied to PET, computed tomography (CT), single photon emission computed tomography (SPECT), microCT, and microPET data. It is in routine clinical use in the Departments of Radiation Oncology and Radiology at Stanford.