Measurements of Breast Tissue Optical Properties
Abstract
Near-infrared (NIR) optical spectroscopy demonstrates unique possibilities for non-invasively monitoring tissue physiology. A bedside-capable instrument using low levels of non-ionizing near-infrared light measured both absorption and scattering properties of tissues. A diffusive model quantified oxygenated and deoxygenated hemoglobin, water, and lipid by their absorption signatures. Cellular density, fat, and collagen content were inferred from measured light-scattering spectra. This quantitative functional information cannot be obtained with other non-invasive radiological techniques. Measurements revealed physiological breast changes consistent with age-dependent histological alterations in over 30 healthy female volunteers. Measurements of several cancer patients demonstrated significant changes in tumor water and hemoglobin saturation values relative to normal tissue. A detailed measurement demonstrated water, hemoglobin saturation, and hemoglobin concentration changes in a breast tumor in direct response to chemotherapy, demonstrating a direct non-invasive measure of tumor angiogenesis. After 3 cycles of chemotherapy, the final tumor was not palpable (5 mm size) but detectable using our technique. Potential applications based upon these findings include monitoring the effectiveness of treatments affecting breast composition (i.e., hormone replacement and chemotherapy), tumor characterization, and evaluating physiologic changes affecting breast cancer risk. The prototype instrument is comparable in cost to commercialized ultrasound.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2001
- Accession Number
- ADB281574
Entities
People
- Albert Cerussi
Organizations
- University of California, Irvine