Portable dual-wavelength amplitude cancellation image system for the determination of human breast tumor

摘要

Abstract: For X-ray mammography, we are unable to apply to younger subjects of woman under 40 years old. The under 40 years old BRCA-1 population has a serious diagnostic problem. So we have chosen to develop an optical technique for breast cancer detection. In order to provide a safe, fast and portable dual wavelength breast imager, we have used high sensitivity cancellation techniques (amplitude cancellation image system) as an imaging system that can better to localize the metabolic and blood volume responses. This device consists of 8 sources (750 nm, 830 nm) and 21 silicon photodiodes. The sources are modulated by 50 us pulse and pulse encode the dual wavelength sources (750 nm, 830 nm). Using programmed amplifies, the image system is first calibrated on a breast model by adjusting all outputs to be equal, hence their differential amplifier outputs are zero. The high sensitive null (zero) plane is applied to detect small objects. By averaging of the imaged data over 8 sec. The system indicated a very high signal to noise ratio (100) in detecting inhomogeneity of the breast with respect to the surrounding tissue or to the contralateral breast in voxeis containing blood volume and oxygenation changes corresponding to the presence of tumors or related tissue pathologies.!5