Phantoms: Library of Computational Human Phantoms

Phantoms text on top of images of different body shapes that are see-through with bones and organs visible

Three-dimensional computerized representations of the human body, referred to as computational phantoms, have been used in the fields of medical physics and radiation protection for decades to study people exposed to medical, occupational, and environmental radiation. Phantoms is a library of state-of-the-art, whole-body computational phantoms representing children and adults of different body height and weight. Each phantom contains more than 100 carefully delineated organs or tissues.

Anatomical Realism

The Phantoms library was developed from x-ray computed tomography (CT) images of patients; it is the product of a collaboration between the University of Florida and the National Cancer Institute.^1,2 Best quality anatomical reference CT images were selected from an archive of 1,000+ patients. More than 100 organs and tissues were manually segmented and reviewed by practicing radiologists.

Human phantoms of different sizes in a row — Reference size computational human phantoms ranging from newborn to adults

The original Phantoms library consisted of a series of reference male and female anatomies (newborn, 1-, 5-, 10-, 15-year-old, and adult) and later extended to 370 phantoms representing children and adults of both genders and various heights and weights.² NCI researchers also added anatomical details such as lymphatic nodes^3,4, substructures of the heart (e.g., atria, ventricles, arteries), and substructures of the brain (e.g., grey and white matter, cerebellum, brain stem).⁵

The Phantoms library was carefully adjusted to match several international reference data including reference person height and weight⁶, organ mass⁶, tissue elemental composition^6,7, and dimensions of gastrointestinal structures⁸. The pediatric phantoms have been adopted by International Commission on Radiological Protection (ICRP) as the international reference.

State-of-the-Art and Versatile Format

Side view of numerous phantoms in a row — A series of the adult male phantoms 175 cm tall and weight ranging from 60 to 130 kg

The Phantoms library was developed using mesh and non-uniform rational B-spline (NURBS) surfaces, the most advanced phantom architecture to date. The phantoms can be converted into voxel format compatible with most Monte Carlo radiation transport codes such as MCNPX, MCNP6, EGSnrc, GEANT4, PHITS. Input decks for these codes describing the phantoms are also available. Some Monte Carlo codes can import the original surface geometry format.

Simulated CT images have been derived for the entire Phantoms library and are written in Digital Imaging and Communications in Medicine (DICOM) CT format. An accompanying DICOM Structure file contains the contours for more than 100 structures included in the phantom. These files have been tested for compatibility on several commercial radiotherapy treatment planning systems (TPS). After importing into a TPS, users can create a treatment plan on the phantom CT and evaluate dose to organs of interest.

Screenshots of different parts of the body — Adult male phantom imported into Eclipse TPS for simulated prostate treatment

How to Access This Resource

Non-Commercial Research Use

There is no charge to use these resources for non-commercial research purposes. Please submit a Software Transfer Agreement form to Dr. Choonsik Lee.

Commercial Use

Contact Dr. Kevin Chang of the NCI Technology Transfer Center to discuss the licensing process for commercial use.

For answers to questions and other support, join the NCI Hub - Group: NCI Dose Forum.