Optical tomography of a realistic neonatal head phantom.
We have begun clinical trials of optical tomography of the neonatal brain. To validate this research, we have built and imaged an anatomically realistic, tissue-equivalent neonatal head phantom that is hollow, allowing contrasting objects to be placed inside it. Images were reconstructed by use of two finite-element meshes, one generated from a computed tomography image of the phantom and the other spherical. The phantom was filled with a liquid of the same optical properties as the outer region, and two perturbations were placed inside. These were successfully imaged with good separation between the absorption and scatter coefficients. The phantom was then refilled with a liquid of increased absorption compared with the background to simulate the brain, and the absolute properties of the two regions were found. These were used as a priori information for the complete reconstruction. Both perturbations were visible, superimposed on the increased absorption of the central region. The head-shaped mesh performed slightly better than the spherical mesh, particularly when the absorption of the central region of the phantom was increased.
Gibson
Adam
A
Department of Medical Physics and Bioengineering, University College London, 11-20 Capper Street, London WC1E 6JA. agibson@medphys.ucl.ac.uk
Yusof
Roza Md
RM
Dehghani
Hamid
H
Riley
Jason
J
Everdell
Nick
N
Richards
Robin
R
Hebden
Jeremy C
JC
Schweiger
Martin
M
Arridge
Simon R
SR
Delpy
David T
DT
D006257:Head; D006801:Humans; D008297:Male; D055095:Optics and Photonics; D019047:Phantoms, Imaging; D014054:Tomography