Molecular imaging using light-absorbing imaging agents and a clinical optical breast imaging system--a phantom study.
OBJECTIVE
The aim of the study was to determine the feasibility of using a clinical optical breast scanner with molecular imaging strategies based on modulating light transmission.


METHODS
Different concentrations of single-walled carbon nanotubes (SWNT; 0.8-20.0 nM) and black hole quencher-3 (BHQ-3; 2.0-32.0 µM) were studied in specifically designed phantoms (200-1,570 mm(3)) with a clinical optical breast scanner using four wavelengths. Each phantom was placed in the scanner tank filled with optical matching medium. Background scans were compared to absorption scans, and reproducibility was assessed.


RESULTS
All SWNT phantoms were detected at four wavelengths, with best results at 684 nm. Higher concentrations (≥8.0 µM) were needed for BHQ-3 detection, with the largest contrast at 684 nm. The optical absorption signal was dependent on phantom size and concentration. Reproducibility was excellent (intraclass correlation 0.93-0.98).


CONCLUSIONS
Nanomolar concentrations of SWNT and micromolar concentrations of BHQ-3 in phantoms were reproducibly detected, showing the potential of light absorbers, with appropriate targeting ligands, as molecular imaging agents for clinical optical breast imaging.
Department of Radiology, Stanford University Medical Center, Stanford, CA, USA.
Stephanie M W Y
SM
van de Ven
Niculae
N
Mincu
Jean
J
Brunette
Guobin
G
Ma
Mario
M
Khayat
Debra M
DM
Ikeda
Sanjiv S
SS
Gambhir
D000042:Absorption / Q000528:radiation effects; D001940:Breast / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D008027:Light; D057054:Molecular Imaging / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry; D055096:Optical Devices; D019047:Phantoms, Imaging; D015203:Reproducibility of Results
D037742:Nanotubes, Carbon