[IPAG Home Page]
- Two dedicated software, voxel-based, anthropomorphic (torso and head) phantoms. I. George Zubal, Ph. D., Charles R. Harrell, Eileen O. Smith, B.S., Amy L. Smith.
- High Resolution, MRI-Based, Segmented,
Computerized Head Phantom. I. George Zubal, Charles R. Harrell, Eileen O. Smith, Amy L. Smith, Paul Krischlunas.
For further information on the phantoms and download instructions see: Zubal Phantom.
Acrobat .pdf Format
Gzipped Postscript Format.
I. George Zubal, Ph. D., Charles R. Harrell, Eileen O. Smith, B.S., Amy
Imaging Processing and Analysis Group
Department of Diagnostic Radiology
333 Cedar Street
Yale University School of Medicine, New Haven, CT 06510
We have segmented CT torso+head and MRI
head slices of two living human males. The manually segmented 129
x-ray CT transverse slices were used to create a computerized
3-dimensional volume array modeling all major internal structures of
the body. The original x-ray CT images were reconstructed in a 512x512
matrix with a resolution of 1 millimeter in the x,y plane. The z-axis
resolution is 1 centimeter from neck to mid-thigh and 0.5 centimeter
from neck to crown of the head. Each voxel of the volume contains an
index number designating it as belonging to a given organ or internal
structure; 68 such index numbers are assigned. The final torso+head
phantom is interpolated to create a 128x128x243 byte volume with
isotropic voxel dimensions of 2.5 mms. Secondly, a dedicated head
phantom was created by similar processing in which 124 transverse MRI
were outlined. The transverse T2 slices, recorded in a 256x256 matrix
have isotropic voxel dimensions of 1.5mm. This dedicated head phantom
contains 62 index numbers designating neurological and taxonomical
structures in the brain, as well as anatomical regions. The final
volume is contained within a 256x256x128 byte array. Both of these
volume arrays represent high resolution models of the human anatomy
and can serve as a voxel-based anthropomorphic phantom suitable for
many computer-based modeling and simulation calculations. We have
applied them to Monte Carlo simulations from which realistic image
projection data has been generated.
I. George Zubal, Charles R. Harrell, Eileen O. Smith, Amy L. Smith, Paul Krischlunas.
Image Processing and Analysis Group,
Dept. of Diagnostic Radiology,
Yale University, New Haven, CT, 06510 USA
Purpose: We have created a high resolution software phantom of the human
brain which is applicable to voxel-based radiation transport calculations
yielding nuclear medicine simulated images and/or internal dose estimates.
Results: A software head phantom was created from 124 transverse MRI images
of a healthy normal. The transverse T2 slices, recorded in a 256x256 matrix
from a GE Signa 2 scanner, have isotropic voxel dimensions of 1.5 mm and
were manually segmented by our clinical staff. Each voxel of the phantom
contains one of 62 index numbers designating anatomical, neurological, and
taxonomical structures. The result is stored as a 256x256x128 byte array.
Internal volumes compare favorably to those described in the ICRP Reference
Man. Conclusion: The computerized array represents a high resolution model
of a typical human brain and serves as a voxel-based anthropomorphic head
phantom suitable for computer based modeling and simulation
calculations. It offers an improved realism over previous mathematically
described software brain phantoms, and creates a reference standard for
comparing results of newly emerging voxel-based computations. Such
voxel-based computations lead the way to developing diagnostic and
dosimetry calculations which can utilize patient specific diagnostic
images. However, such individualized approaches lack fast, automatic
segmentation schemes for routine use; therefore, our high resolution,
typical head geometry gives the most realistic patient model currently
You may need to install Adobe
Acrobat Reader to view or print these files. (Alternatively on
unix machines try xpdf.)
Questions regarding the content of this page should be directed to
Questions or bug reports regarding this interface should go to