RESUMEN
A method has been devised for generating three-dimensional optical images of the breast using a 32-channel time-resolved system and a liquid-coupled interface. The breast is placed in a hemispherical cup surrounded by sources and detectors, and the remaining space is filled with a fluid with tissue-like optical properties. This approach has three significant benefits. First, cups can accommodate a large range of breast sizes, enabling the entire volume of the breast to be sampled. Second, the coupling of the source and detector optics at the surface is constant and independent of the subject, enabling intensity measurements to be employed in the image reconstruction. Third, the external geometry of the reconstructed volume is known exactly. Images of isolated targets with contrasting absorbing and scattering properties have been acquired, and the performance of the system has been evaluated in terms of the contrast, spatial resolution, and localization accuracy. These parameters were strongly dependent on the location of the targets within the imaged volume. Preliminary images of a healthy human subject are also presented, which reveal subtle heterogeneity, particularly in the distribution of scatter. The ability to detect an absorbing target adjacent to the breast is also demonstrated.
Asunto(s)
Mama/citología , Tecnología de Fibra Óptica/instrumentación , Aumento de la Imagen/instrumentación , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Espectrofotometría Infrarroja/instrumentación , Tomografía Óptica/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Tecnología de Fibra Óptica/métodos , Humanos , Aumento de la Imagen/métodos , Mamografía/instrumentación , Mamografía/métodos , Proyectos Piloto , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Soluciones , Espectrofotometría Infrarroja/métodos , Tomografía Óptica/métodosRESUMEN
Results are presented of a study to monitor the changes in the optical properties of breast tissue over a 12-month period after interstitial laser photocoagulation treatment of a fibroadenoma. The study involved generating cross-sectional images of the breast with a multichannel time-resolved imaging system and a nonlinear image reconstruction algorithm. Images of the internal absorbing and scattering properties revealed the expected initial inflammatory response, followed by the development of low-scattering cysts consistent with corresponding ultrasound examinations. Although results indicate that purely qualitative images can potentially provide clinically valuable data, means of enhancing diagnostic information by overcoming present limitations of the approach are discussed.