Fast coregistered breast imaging in vivo using a hand-held optical imager

Abstract

A hand-held optical imaging device has been developed in our laboratory towards fast 2D imaging and 3D tomography for breast cancer diagnosis. The device has the unique abilities: (1) to contour to different tissue curvatures using a flexible probe face; (2) perform fast 2D imaging by employing simultaneous over sequential source illumination; and (3) self coregistration towards (future) 3D tomography. The objective of the current work is to demonstrate fast coregistered 2D imaging on breast tissue of healthy female subjects. Fluorescence imaging experiments are performed in vitro and in vivo to demonstrate coregistered imaging as well as the ability to detect deep targets from multiple surface scans. A 0.45 cc spherical target filled with 1 µM indocyanine green is embedded at various depths of a cubical phantom filled with chicken breast (in vitro models). For in vivo studies, the fluorescent target is placed under the flap of the breast tissue to represent a tumor for fluorescence imaging. Multiple scans (fast continuous-wave images of fluorescence intensity) are collected and coregistered at different locations on the breast tissue. This study demonstrates the potential of the hand-held optical device towards future in vivo surface imaging and tomographic imaging for 3D tumor localization.

Three-dimensional fluorescence tomography of human breast tissuesin vivousing a hand-held optical imager

“…The probe was steadier at location 1 than location 3 because it was supported by the chest wall. The average total distance off between the true and tracked location is ∼1 cm, which is much higher than that previously determined from a cubical phantom (∼0.19 cm) (Erickson et al 2010b). This can be attributed to: (i) instability in the tracker leading to fluctuations in the tracked position of the probe (Regalado et al 2010, Martinez et al 2010; and (ii) human error such as hand movement of the operator across the 10 measurement repetitions and manual measurement of the reference points on the tissue.…”