Effect of the chest wall on breast lesion reconstruction.

The chest wall underneath the breast tissue affects near-infrared (NIR) diffusive waves measured with reflection geometry. With the assistance of a co-registered ultrasound, the depth and the tilting angle of the chest wall can be determined and are used to model the breast as a two-layer medium. Finite element method (FEM) is suitable for modeling complex boundary conditions and is adapted to model the breast tissue and chest wall.

Accuracy and reproducibility of tumor positioning during prolonged and multi-modality animal imaging studies.

Dedicated small-animal imaging devices, e.g. positron emission tomography (PET), computed tomography (CT) and magnetic resonance imaging (MRI) scanners, are being increasingly used for translational molecular imaging studies.

Benign versus malignant breast masses: optical differentiation with US-guided optical imaging reconstruction.

Purpose: To investigate prospectively the feasibility of using optical tomography with ultrasonographic (US) localization to differentiate malignant from benign breast masses and to compare optical tomography with color Doppler US.

Materials And Methods: The study was approved by the local internal review board committee and by the Human Subjects Research Review Board of Army Medical Research and Materiel Command. Signed informed consent was obtained, and the study was HIPAA compliant.

Utilizing optical tomography with ultrasound localization to image heterogeneous hemoglobin distribution in large breast cancers.

Purpose: Angiogenesis in advanced breast cancers is highly distorted and heterogeneous. Noninvasive imaging that can monitor angiogenesis may be invaluable initially for diagnosis and then for assessing tumor response to treatment. By combining ultrasound (US) and near-infrared (NIR) optical imaging, a reliable new technique has emerged for localizing and characterizing tumor angiogenesis within the breast.

Portable near-infrared diffusive light imager for breast cancer detection.

We present a frequency-domain near-infrared optical tomography system designed for breast cancer detection, in conjunction with conventional ultrasound. It features fast optical switching, three-wavelength excitations, and avalanche photodiode as detectors. Laser diodes at 660, 780, and 830 nm are used as light sources and their outputs are distributed sequentially to one of nine source fibers.

Dual-mesh optical tomography reconstruction method with a depth correction that uses a priori ultrasound information.

A dual-mesh reconstruction method with a depth correction for near-infrared diffused wave imaging with ultrasound localization is demonstrated by use of phantoms and clinical cancer cases. Column normalization is applied to the weight matrix obtained from the Born approximation to correct the depth-dependent problem in the reconstructed absorption maps as well as in the total hemoglobin concentration maps. With the depth correction, more uniform absorption maps for target layers at different depths are obtained from the phantoms, and the correlation between the reconstructed hemoglobin concentration maps of deeply located, large cancers and the histological microvessel density counts are dramatically improved.

Ultrasound-guided optical tomographic imaging of malignant and benign breast lesions: initial clinical results of 19 cases.

The diagnosis of solid benign and malignant tumors presents a unique challenge to all noninvasive imaging modalities. Ultrasound is used in conjunction with mammography to differentiate simple cysts from solid lesions. However, the overlapping appearances of benign and malignant lesions make ultrasound less useful in differentiating solid lesions, resulting in a large number of benign biopsies.

Simultaneous reconstruction of absorption and scattering maps with ultrasound localization: feasibility study using transmission geometry.

We report the experimental results of the simultaneous reconstruction of absorption and scattering coefficient maps with ultrasound localization. Near-infrared (NIR) data were obtained from frequency domain and dc systems with source and detector fibers configured in transmission geometry. High- or low-contrast targets located close to either the boundary or the center of the turbid medium were reconstructed by using NIR data only and NIR data with ultrasound localization.