Abstract: An image acquisition system and method for generating a subtracted image motion picture as an imaging device moves relative to a subject includes an imaging device for first generating a sequence of first image frames as the imaging device moves along an imaging path under operator control and later generating a sequence of second image frames as the imaging device automatically moves along the same imaging path under processor control. Motion along the imaging path can be duplicated by sensing and storing information indicative of the position of the imaging device relative to the subject as a function of time and later commanding servo motors connected to the imaging device using that position information. Each frame in the first and second sequence of frames has position information stored therewith identifying the location along the imaging path at which each frame was generated.

Abstract: An apparatus is described for moving a probe (12) that engages moving living tissue such as a heart or an artery that is penetrated by the probe, which moves the probe in synchronism with the tissue to maintain the probe at a constant location with respect to the tissue. The apparatus includes a servo positioner (18) which moves a servo member (20) to maintain a constant distance from a sensed object (30) while applying very little force to the sensed object, and a follower (26) having a stirrup (28) at one end resting on a surface of the living tissue and another end carrying a sensed object (30) adjacent to the servo member. A probe holder (34) has one end mounted on the servo member (20) and another end which holds the probe (12). The probe is held adjacent to the stirrup (28) of the follower assembly, so that movements of the tissue and therefore of the follower assembly (26) result in corresponding movement of the probe (12) to follow the surface of the tissue.

Abstract: A method and apparatus for angiography in which information contained within multiple serial images of contrast medium flowing through a blood vessel is combined to form a single image having improved vessel edge delineation. More specifically, a method is disclosed whereby a contrast medium opaque to X-rays is injected into a blood vessel distant from an artery section of interest, preferably injected into a vein, whereby the contrast medium is mixed with blood prior to its passing through the artery section. Multiple X-ray images are obtained as the contrast medium and blood mixture flows through the artery section. These multiple images are registered with respect to each other according to a landmark contained within the patient, the landmark having a predetermined relationship to the vessel of interest. The landmark could be a bone, catheter or any other material opaque to X-rays.

Abstract: An arrangement for and method of inserting a glass microelectrode having a tip in the micron range into body tissue is disclosed. The arrangement includes a microelectrode. The top of the microelectrode is attached to the diaphragm center of a first speaker. The microelectrode tip is brought into contact with the tissue by controlling a micromanipulator. Thereafter, an audio signal is applied to the speaker to cause the microelectrode to vibrate and thereby pierce the tissue surface without breaking the microelectrode tip. Thereafter, the tip is inserted into the tissue to the desired depth by operating the micromanipulator with the microelectrode in a vibratory or non-vibratory state. A mechanism including a second speaker disclosed. Such mechanism is useful to sense tissue motion to control the microelectrode position with respect thereto substantially constant.