Near-Infrared Hand-Held Optical Imaging Technology

Abstract

Diffuse optical imaging is an emerging technology in the fi eld of non-invasive breast cancer imaging and functional brain mapping. A review of the various imagers developed to date for breast cancer is described. These imagers can be broadly classifi ed into bed-based, parallel plate, and hand-held. With hand-held optical imagers, work to date has been focused on 2D refl ectance-based spectroscopic imaging of breast tumors. A hand-held optical imager capable of refl ectance and transillumination imaging has been developed at the Optical Imaging Laboratory to allow deep target detection. Experiments have been performed on tissue phantoms that demonstrated detection of 5 cm deep targets via transillumination imaging, compared to 2.5 cm deep targets via refl ectance imaging. Multiple targets were resolved from 2D experimental studies, when placed 1.5 cm apart even at target depths of 2 cm. Preliminary in vivo studies on breast tissues demonstrated that pressure placed a signifi cant role in detecting the target regions during 2D refl ectance imaging studies. The ongoing research efforts focus on demonstrating the 3D tomographic imaging capability of the hand-held imager for volumetric tumor localization in any breast volume and curvature.