Abstract: Apparatus and methods are provided for correlating radiologic and ultrasonic images of biological tissue. An X-ray image and a plurality of corresponding ultrasound images are generated while the biological tissue remains immobilized. X-ray opaque indexing points provide lateral registration of the X-ray film with the ultrasound apparatus. The fan-out of X-ray beams penetrating the tissue from a point X-ray source is determined and used to correlate the X-ray image data to the ultrasonic image data. Apparatus and methods are also provided for determining the location of the X-ray source relative to the indexing points.

Abstract: Apparatus and methods are provided for performing an in situ characterization of a tissue mass which may be normal, malignant, or benign, and, based on the measured characteristics of the tissue mass, therapeutically treating the tissue mass to cause necrosis of the tissue. In an illustrative preferred embodiment, the characterization of the tissue is accomplished by measuring an electrical property of the tissue, such as electrical impedance, while treatment is accomplished by supplying heat to the tissue to induce cauterization.

Abstract: Apparatus is provided that combines mammography equipment with an ultrasonic transducer to generate ultrasonic images of the internal structure of breast tissue that are in geometric registration with a mammogram. The apparatus includes a radiolucent and sonolucent compression plate, and in alternative embodiments, a gantry driven ultrasound transducer or a phased array ultrasonic transducer. Methods are provided for generating a mammogram and a plurality of corresponding ultrasound images without moving the breast between the mammogram exposure and the ultrasound imaging. Methods are also provided for viewing and analyzing the ultrasound images. Apparatus and methods are also provided for enhancing X-ray images obtained from conventional mammographic systems, and with reduced overall X-ray dosage to the patient.

Abstract: Apparatus is provided that combines mammography equipment with an ultrasonic transducer to generate ultrasonic images of the internal structure of breast tissue that are in geometric registration with a mammogram. The apparatus includes a radiolucent and sonolucent compression plate, and in alternative embodiments, a gantry driven ultrasound transducer or a phased array ultrasonic transducer. Methods are also provided for generating a mammogram and a plurality of corresponding ultrasound images without moving the breast between the mammogram exposure and the ultrasound imaging.

Abstract: A method for accentuating the differences in blood perfusion between normal and tumorous tissue is provided which comprises the steps of measuring the blood perfusion in a local area of the body, heating the local area, then measuring the blood perfusion for variations or inhomogenieties in blood perfusion after the local area has been subjected to heating. As a result of heating normal tissue will generally exhibit increased blood perfusion compared with its preheated condition and as compared with blood perfusion in tumorous tissue, rendering the tumorous tissue more susceptible to detection by techniques such as ultrasonic Doppler blood flow measurement. Apparatus for performing the inventive method is described, including an ultrasonic scanhead which includes a high intensity transducer for heating tissue to be scanned, and an array transducer for performing Doppler measurements of the tissue before and after it has been heated.