Abstract: An apparatus and method for imaging a small cavity is disclosed wherein reference waveforms to be used in obtaining an improved image are generated in vivo instead of in vitro as is the conventional procedure. The reference waveforms are used to strip the imaging signals of noise that otherwise produces artifacts in an image generated from the signals. The imaging probe is first inserted into a first area of the vascular system to be imaged and reference waveforms are collected. After collecting the reference waveforms, the imaging probe is further inserted into the vascular system to a second area that is to be imaged. If new reference waveforms are required, the imaging probe is simply withdrawn to the first area of the vascular system wherein new reference waveforms are collected, and then the imaging probe is again further inserted to the second area, which then is imaged.

Abstract: A dilating and imaging apparatus for attaching to and receiving pressurized fluid from a distal end of a catheter. The apparatus includes an inflatable balloon and an imaging device positioned behind an expandable portion of the balloon and upstream of the flow of pressurized fluid into the balloon so as to enable the balloon to deflate and achieve a smaller diameter than that of the imaging device, thus enabling the apparatus to enter a stenosis having a smaller diameter than the imaging device. In one embodiment of the invention, the imaging device can be maneuvered within the balloon while the balloon is inflated and dilating the stenosis.

Abstract: A self-venting balloon dilatation catheter and method for producing the same having a catheter tubing including a first lumen and a second lumen. An expandable balloon is positioned at a distal end of the catheter tubing. The first lumen is for a guide wire and the second lumen is in communication with the interior of the balloon. The balloon is expanded by filling the balloon with pressurized fluid via the second lumen. An air vent within the catheter tubing purges air from the balloon when the balloon is filled with fluid. Air purged via the air vent first moves substantially transverse to a longitudinal axis of the catheter tubing and then along the longitudinal axis to an opening at a distal end of the catheter tubing. A cylindrically marker band is secured around the distal end of the catheter tuving, and another cylindrical marker band is secured around the catheter tubing inside the expandable balloon.

Abstract: An in vivo imaging device is provided for producing real-time images of small, moving or stationary cavities and surrounding tissue structure. The imaging device includes a probe assembly of very small dimensions and preferably sufficiently small to fit within cavities having a diameter on the order of that of a human coronary artery. The probe assembly may be mounted to a positioning device such as a catheter, which allows for the use of, for example, conventional guiding catheters and guide wires.