Surgery – Diagnostic testing – Detecting nuclear – electromagnetic – or ultrasonic radiation
Reexamination Certificate
2001-10-11
2004-02-24
Mercader, Eleni Mantis (Department: 3737)
Surgery
Diagnostic testing
Detecting nuclear, electromagnetic, or ultrasonic radiation
C601S004000, C604S022000
Reexamination Certificate
active
06695782
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates generally to medical devices, and more particularly to an apparatus and method for using an ultrasonic medical devices operating in a transverse mode emulsification of endovascular materials by causing tissue fragmentation of occlusion materials. The invention also relates to an apparatus emitting ultrasonic energy in transverse mode used in combination with an elongated flexible catheter wire, wherein the probe is rapidly attachable to and detachable from the ultrasonic energy source component of the device.
BACKGROUND OF THE INVENTION
Vascular occlusions (clots or thrombi and occlusional deposits, such as calcium, fatty deposits, or plaque) result in the restriction or blockage of blood flow in the vessels in which they occur. Occlusions result in oxygen deprivation (“ischemia”) of tissues supplied by these blood vessels. Prolonged ischemia results in permanent damage of tissue that can lead to myocardial infarction, stroke, or death. Targets for occlusion include coronary arteries, peripheral arteries and other blood vessels. The disruption of an occlusion or thrombolysis can be effected by pharmacological agents and/or or mechanical means.
Ultrasonic probes are devices which use ultrasonic energy to fragment body tissue (see, e.g., U.S. Pat. Nos. 5,112,300; 5,180,363; 4,989,583; 4,931,047; 4,922,902; and 3,805,787) and have been used in many surgical procedures. The use of ultrasonic energy has been proposed both to mechanically disrupt clots, and to enhance the intravascular delivery of drugs to clot formations (see, e.g., U.S. Pat. Nos. 5,725,494; 5,728,062; and 5,735,811). Ultrasonic devices used for vascular treatments typically comprise an extra-corporeal transducer coupled to a solid metal wire that is attached to a plurality of wires at the distal end, that is then threaded through the blood vessel and placed in contact with the occlusion (see, e.g., U.S. Pat. No. 5,269,297). In some cases, the transducer is delivered to the site of the clot, the transducer comprising a bendable plate (see, U.S. Pat. No. 5,931,805).
The ultrasonic energy produced by an ultrasonic probe is in the form of very intense, high frequency sound vibrations that result in powerful chemical and physical reactions in the water molecules within a body tissue or surrounding fluids in proximity to the probe. These reactions ultimately result in a process called “cavitation,” which can be thought of as a form of cold (i.e., non-thermal) boiling of the water in the body tissue, such that microscopic bubbles are rapidly created and destroyed in the water creating cavities in their wake. As surrounding water molecules rush in to fill the cavity created by collapsed bubbles, they collide with each other with great force. This process is called cavitation and results in shock waves running outward from the collapsed bubbles which can fragment or ablate material such as surrounding tissue in the vicinity of the probe.
Some ultrasonic probes include a mechanism for irrigating an area where the ultrasonic treatment is being performed (e.g., a body cavity or lumen) to wash tissue debris from the area. Mechanisms used for irrigation or aspiration described in the art are generally structured such that they increase the overall cross-sectional profile of the probe, by including inner and outer concentric lumens within the probe to provide irrigation and aspiration channels for removal of particulate matter. In addition to making the probe more invasive, prior art probes also maintain a strict orientation of the aspiration and the irrigation mechanism, such that the inner and outer lumens for irrigation and aspiration remain in a fixed position relative to one another, which is generally closely adjacent the area of treatment. Thus, the irrigation lumen does not extend beyond the suction lumen (i.e., there is no movement of the lumens relative to one another) and any aspiration is limited to picking up fluid and/or tissue remnants within the defined distance between the two lumens.
Another drawback of existing ultrasonic medical probes is that they typically remove tissue relatively slowly in comparison to instruments that excise tissue by mechanical cutting. Part of the reason for this is that existing ultrasonic devices rely on a longitudinal vibration of the tip of the probe for their tissue-disrupting effects. Because the tip of the probe is vibrated in a direction in line with the longitudinal axis of the probe, a tissue-destroying effect is only generated at the tip of the probe. One solution that has been proposed is to vibrate the tip of the probe in a direction other than perpendicular to the longitudinal axis of the probe, in addition to vibrating the tip in the longitudinal direction. It is proposed that such motions will supplement the main point of tissue destruction, which is at the probe tip, since efficiency is determined by surface area of the probe tip. For example, U.S. Pat. No. 4,961,424 to Kubota, et al. discloses an ultrasonic treatment device that produces both a primary longitudinal motion, and a supplementary lateral motion of the probe tip to increase the tissue disrupting efficiency. The Kubota, et al. device, however, still relies primarily on the tip of the probe to act as a working surface. The ancillary lateral motion of the probe is intended to provide an incremental efficiency for the device operation. Thus, while destruction of tissue in proximity to the tip of the probe is more efficient, tissue destruction is still predominantly limited to the area in the immediate vicinity at the tip of the probe. The said invention is therefore limited in its ability to ablate tissue within inner surfaces of cylindrical blood vessels, for example, in vascular occlusions. U.S. Pat. No. 4,504,264 to Kelman discloses an ultrasonic treatment device containing a probe that is capable of longitudinal vibrations and lateral oscillation. The said invention is intended to improve the efficiency of ultrasonic tissue removal by providing a dual function of a fragmentation and a cutting device. Tissue fragmentation is caused primarily by oscillating the tip of the probe in addition to relying on longitudinal vibrations of the probe, while the lateral oscillations. Tissue fragmentation is caused primarily at the tip of the device, while the oscillatory motion can be employed by the surgeon to cut tissue, thereby increasing efficiency of surgical procedures. The foregoing inventions also require complex instrument design that require incorporation of a plurality of electrodes, ultrasound frequency generating elements, switches or voltage controllers.
The longitudinal probe vibration required for tissue ablation in prior art devices necessitates the probe lengths to be relatively short, since use of long probes result in a substantial loss of ultrasonic energy at the probe tip due to thermal dissipation and undesirable horizontal vibration that interferes with the required longitudinal vibration.
Although narrow probe diameters are advantages especially for negotiation through narrow blood vessels and occluded arteries, the utilization of such probes have been precluded by inability to effectively control the vibrational amplitude of thin probes, that result in potential damage to the probe and greater risk of tissue damage resulting from their use. The use of narrow-diameter probes have been disclosed in the art for providing greater maneuverability ease of insertion in narrow blood vessels. U.S. Pat. No. 4,920,954 to Allinger discloses a narrow diameter ultrasonic device wherein a rigid sleeve is used to prevent transverse vibrations U.S. Pat. No. 5,380,274 discloses a narrow diameter probe for improved longitudinal vibration having a sheath to inhibit transverse vibration U.S. Pat. No. 5,469,853 to Law discloses a thin, longitudinally vibrating ultrasonic device with a bendable sheath that facilitates directing the probe within narrow blood vessels. While the prior art has focused on the need for using sheaths on thin ultrasonic devices, their use
Hare Bradley A.
Marciante Rebecca I.
Rabiner Robert A.
Ranucci Kevin
Robertson Roy
Dykeman David J.
Mantis Mercader Eleni
OmniSonics Medical Technologies, Inc.
Palmer & Dodge LLP
Smith Richard B.
LandOfFree
Ultrasonic probe device with rapid attachment and detachment... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ultrasonic probe device with rapid attachment and detachment..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ultrasonic probe device with rapid attachment and detachment... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3285216