Patent Description:
The devices of the invention are applicable for various types of intrabody surgery including, but not limited to cutting, breaking, coagulation, vaporization of any body tissue (including but limited to soft tissue includes tendons, ligaments, fascia, skin, fibrous tissues, fat, and synovial membranes, etc.; and muscles, nerves and blood vessels (which are not connective tissue) as well as hard tissue/bone and connective tissue, etc.) which involves reaching the targeted tissue through body channels including but not limited to blood vessels, ureter, oesophagus, stomach and duodenum (esophagogastroduodenoscopy), small intestine (enteroscopy), largeintestine/colon (colonoscopy, sigmoidoscopy) or incision or cut through the body tissues (laparoscopic surgery) or similar.

Although devices for removal of the occluding material from the blood vessels as well as other body lumens are discussed below in greater detail, it should be absolutely clear that this is one of many possible applications of the invention. In fact, devices of the invention are applicable to many types of intrabody surgery, as identified above.

Cardiovascular diseases frequently arise from the accumulation of atheromatous material on the inner walls of vascular lumens, particularly arterial lumens of the coronary, peripheral and other vasculature, resulting in a condition known as atherosclerosis. Atheromatous and other intravascular deposits restrict blood flow and can cause ischemia which, in acute cases, can result in myocardial infarction or a heart attack, stroke or aneurysm. Atheromatous deposits can have widely varying properties, with some deposits being relatively soft and others being fibrous and/or calcified. In the latter case, the deposits are frequently referred to as plaque. Atherosclerosis occurs naturally as a result of aging but may also be aggravated by factors such as diet, hypertension, heredity, vascular injury, and the like.

Atherosclerosis can be treated in a variety of ways, including drugs, bypass surgery, and a variety of catheter-based approaches which rely on intravascular widening or removal of the atheromatous or other material occluding the blood vessel. Specific catheter-based interventions include angioplasty, atherectomy, RF ablation cutting devices, stenting, and the like. For the most part, however, this can be difficult or impossible in tortuous regions of the vasculature. Moreover, the catheters used for these interventions are often introduced over a guidewire, and the guidewire is placed across the lesion prior to catheter placement. Initial guidewire placement can be equally difficult if it needs to be placed through a long and multidirectional vasculature. This is especially so when the lesion occludes the blood vessel lumen to such an extent that the guidewire cannot be advanced across the lesion.

Occlusion in a blood vessel can be caused by a variety of materials from hard bone like calcium deposits to soft blood clot or piece of fatty deposit. Multiple type occlusions may be present in the same vessel. Currently different tools are used to remove different types of occlusion. Surgeons may need to remove one type of catheter and replace it with another one in order to work with different occlusion types. This extends treatment time, substantially raises cost, and increase risk for a patient. The disclosure provide a more optimal and complete solution to this problem which include means to analyze the type of occlusion material present and then adapt the function of the occlusion removal device accordingly. Furthermore, the disclosure provides a combinational arrangement which enables sergeants to successfully work with different occlusion types without the need to remove one type of catheter/cutting tool and replace it with another one.

In prior art, there are known rotational atherectomy systems utilizing diamond drill tips/burrs to sand hard calcified occlusions to very small particles. While there are some discussions that the particles produced from 20µmdiamond -tipped burr that ablates plaque into micro-particles are smaller in size (~<NUM>) than a red blood cell (<NUM>), it is also known that larger particles of debris, produced when occlusion is being broken, are generated. Such larger particles can block blood capillaries and cause serious side effects. However, even when the occlusion particles are as small as blood cells, their presence in the blood stream may present a potential risk. Especially if such particles are accumulated at the essential body tissues, causing malfunctioning of the vital body organs. Visible accumulation of even smaller particles, for example tattoo ink particles (less than <NUM>µtm (<NUM>)), is well known. The tattoos particles accumulation (tattoo) is well known to be permanent or at least long term. Since the tattoo ink is inserted into the skin, it mostly stays in the dermis. Thus, the impact of the ink particles on other tissue and organs is localized. On the other hand, since the particles generated during the occlusion destruction can be carried out through the blood stream to the vital body organs, proper management of such becomes important. Some of the rotational atherectomy catheters have built-in arrangements with active aspiration to remove debris from the blood stream and evacuate the debris through the catheter or catch them into a separately inserted catch-basket downstream the blood vessel post occlusion zone. However, these aspiration (debris evacuation) arrangements are not optimally designed to remove all or most of such debris particles. The inventions propose more optimal and complete solutions to this problem.

The prior art solutions for removal of calcium plaque are often provided with forwardly shaped rotational drills. Such design presents a risk of accidental perforation of the blood vessel walls if such drill is pushed against the wall during the procedure. One of the aspects of the invention provides ways to limit such risks of vessel wall perforation as well as minimizes negative aspects of the procedure on any adjacent tissue.

The prior art is known for drill with the center of mass off center of the axis of burr rotation. This creates the centrifugal force which allows the burr to drill a wider opening in the lumen. However, it also leads to potential injuring of the vessel walls. This is because operators cannot control the application of centrifugal force which is constantly present in prior art devices. Injuring the blood vessel walls during atherectomy surgery is one of the leading causes of post atherectomy procedure restenosis -soft tissue growth from the vessel walls that closes the vessel lumen with soft occlusion.

The present disclosure offers a solution to prevent unwanted damage to the vessel walls by creating a mechanism allowing an operator to remotely alter the position of the burr's center of mass as needed for the specific surgery site requirements.

In prior art, there are known rotational atherectomy systems utilizing diamond drill tips/burrs to sand hard calcified occlusions to very small particles. However, such drills are not suitable or effective in removing soft occlusions. The present invention offers solutions allowing use of mechanical drills to safely and effectively cut and remove both hard and soft occlusions in the vessels including in-stent restenosis ISR growth. The device of the invention is acceptable in orthopedic and other types of body surgery.

<CIT> discloses a capturing unit provided on a distal end of a second tube can be deformed into a contracted state and an expanded state, in which the capturing unit is deployed to form a capturing chamber. The capturing chamber has an opening area decreased as it goes from a distal end opening of the capturing chamber toward a proximal end opening of the capturing chamber. A third tube rotatable relative to the second tube and a cutting unit provided on a distal end of the third tube for cutting a foreign substance are arranged in a second lumen. <CIT> discloses a method and device for tissue removal. The device may be used to remove uterine fibroids and other abnormal gynecological tissue. According to one embodiment, the device includes a housing, an outer tube, and an inner tube. The outer tube is fixed to the housing and includes a side window proximate to its distal end. The side window may have sloped proximal and distal ends. The inner tube has a distal end positioned within the outer tube, the distal end being adapted to rotate and, at the same time, to move back and forth past the side window, with the rotational and translational movement of the inner tube being independently controllable. The distal end of the inner tube may have an external bevel.

<CIT> discloses devices and methods generally relating to treatment of occluded body lumens. In particular, the devices and method relate to removal of the occluding material from the blood vessels as well as other body lumens.

In accordance with the invention, there is provided a device for intrabody surgery as set forth in claim <NUM> of the appended claims. Embodiments are provided in the dependent claims. The methods of operation disclosed are not explicitly recited by the wording of the claims but are considered useful for understanding the invention.

In the following drawings, the same parts in the various views are afforded the same reference designators. Referring now to the drawings which are provided to illustrate and not to limit the invention, wherein:.

As used herein in the description of various components, "proximal" refers to a direction toward the system controls and the operator, and "distal" refers to the direction away from the system controls and the operator and toward a terminal end of the cutter assembly. In general, the material removal device of the present invention may be used in a system comprising a control unit attached to one end of a catheter assembly and an axially translatable, rotatable drive shaft, with a cutter assembly positioned at the distal end of the drive shaft at least partially supported by the guidewire. The material removal device of the invention further comprises multiple sensors positioned at the cutter assembly area and along the length of the catheter. In one embodiment the system includes wires associated with sensors as well as with delivery of electric power to ultrasound or RF emitters.

The cutter assembly is translated over a guidewire to the material removal site and is actuated at the material removal site to cut, grind, or ablate, or otherwise remove, the occlusive material. The control unit, and manifold assembly remain outside the body during a material removal operation.

We are referring now to <FIG> illustrating a catheter assembly <NUM> of one embodiment falling outside of the scope of the invention provided for passing a high-rotational-speed burr/cutter <NUM> into blood vessels as well as to other bodily cavities and adapted to ablate and remove abnormal occlusions and deposits. The burr/cutter20 actuated by a driveshaft 30and guided through the vessel to the application area by the guidewire <NUM>, drills and cuts away the occlusions in the blood vessel.

The flexible guidewire <NUM> is navigated through one or more lumens such as blood vessels, to a desired material removal site. The catheter assembly <NUM> generally houses the burr/cutter <NUM>, drive shaft <NUM>, which also defines a lumen32 which is used among other purposes for the aspiration and/or infusion of fluids. The catheter assembly <NUM> may be fixed to and advanced in concert with the drive shaft <NUM> to actuate a cutter assembly. The guidewire <NUM> and the catheter assembly <NUM> are introduced into a lumen of a patient and navigated or guided to the site of the desired material removal operation.

A proximal end <NUM> of the drive shaft is operably connected to vacuum or infusion pumps, while a distal end <NUM> of the drive shaft is operably connected to cutter/burr <NUM>. Drive shaft <NUM> is preferably a flexible, hollow, helical, torque-transmitting shaft.

The burr/cutter20 is formed having teardrop-shaped head <NUM> with a substantially hollow front cutting exterior region <NUM> and a substantially solid rear region <NUM>. The front region <NUM> facing the occlusions formed by longitudinal drilling sections <NUM> extending along longitudinal axis of the cutter interconnected by transversely oriented cutting blade sections <NUM>. The drilling sections <NUM> are positioned at an angle to each other defining in combination with the transverse cutting blades <NUM> a conically shaped grid formation culminating at a front tip <NUM> of the head <NUM>. An internal hollow cavity <NUM> is formed inside of the grid formation with a central bore <NUM> passing through the rear region <NUM> and a connecting element <NUM>. The grid formation defines a plurality of ports <NUM> between the drilling sections <NUM> and the blades <NUM>. The central bore <NUM> and the internal cavity <NUM> extend longitudinally passing through the central part of the burr/cutter body and are adapted to movably receive the guidewire <NUM>. The cutter/burr <NUM> is mounted at the distal end <NUM> of a flexible drive shaft <NUM> which transmits torque from a torque-generating device (not shown), such as an electric or pneumatic motor. The drive shaft <NUM> is guided by and surrounds a substantial portion of the hollow guidewire <NUM>. It will be discussed that ports <NUM> provide passage of debris from the exterior of cutter/burr to the central bore <NUM> and the internal cavity <NUM>. Optionally, ports <NUM> can be also provided in the rear region <NUM>. The connecting element <NUM> extends from the rear region <NUM> of the burr in the proximal direction for connection to the distal end <NUM> of the drive shaft. In one background embodiment the connecting element <NUM> has a cylindrical shape. On the other hand, any conventional configurations of the connecting element <NUM> are within the scope of the disclosure.

As discussed later in the application, optionally a stop member <NUM>(see <FIG>) can be provided at the proximal end of the connecting element <NUM>.

A plurality of ports <NUM> connects the exterior surface of the burr with its internal cavity <NUM> connected to the lumen <NUM> and providing for aspiration of the debris created from drilling of the hard occlusion or cutting of the soft occlusion material. As illustrated in <FIG>, a central bore <NUM> passes through the burr/cutter to the internal cavity <NUM>. The bore <NUM> is larger than an outer diameter of the guidewire <NUM>, so that drive shaft <NUM> with the cutter <NUM> are slidable and easily translatable over guidewire <NUM>. The longitudinal drilling sections <NUM> and cutting blades <NUM> are formed with sharp edges defining outer cutting surfaces. Cutting blades36 and longitudinal drilling sections24 may have sharpened edges to provide cutting and ablation. The longitudinal drilling sections24 and cutting edges are arranged to direct debris produced during the cutting operation into the interior of the head <NUM> through the multiple ports <NUM>. Longitudinal drilling sections <NUM> and cutting blades36 may, additionally or alternatively, have an abrasive or cutting material bonded to one or more surfaces of longitudinal drilling sections24 Material such as diamond grit is an example of suitable abrasive.

In one embodiment the cutting blades <NUM> are arranged in a radially symmetrical configuration. In another embodiment the cutting blades are asymmetrically arranged regarding a longitudinal axis of the head <NUM>.

In the background embodiment ports/openings <NUM> are formed within the front region <NUM> of the cutter/burr, to provide communication with the internal cavity <NUM>. More specifically, the ports <NUM> provide communication between the cutting front region <NUM> engaging the occlusion with the internal cavity <NUM> and provide communication with the apertures <NUM> of the guide wire <NUM> disposed within the cavity48.

Particles resulting from operation of the burr/cutter <NUM> are properly removed to prevent penetration into a blood stream. Debris particles resulted from use of the burr/cutter <NUM> are drawn through the ports <NUM> into internal cavity <NUM> by low pressure zone created in internal cavity by a vacuum pump connected to the distal end <NUM> of the drive shaft. Ports <NUM> also allow debris produced during the operation of the burr <NUM> to be aspired into the ports <NUM> in the guide wire. It will be discussed in greater detail below that the guide wire <NUM> made as a hollow tubular structure is also used as a suction/aspiration conduit for aspiration of occlusion debris, as the burr/cutter20 drills away the occlusion. As discussed above, in an alternate background embodiment, the ports <NUM> can be also provided within the rear portion <NUM> of the burr. The guide wire can be removed after the burr/cutter <NUM> is guided within the body lumen to the occlusion. Thus, the entire internal cavity <NUM> of the burr and the lumen <NUM> of the shaft can be used for aspiration purposes.

The front region <NUM> of the cuter facing the occlusion may have coatings on its inside or outside for various purposes, for example, for protection against corrosion by body fluids or for insulation against the high energy emitted towards its distal region. It can be of any dimension convenient for its intended use.

Additional structures at the front region <NUM> may help to prevent clogging of the suction conduit. For example, a filter, a screen, a mesh, a shield, or other barriers can be provided at the distal region of the suction conduit.

In an alternate background embodiment, as illustrated in <FIG> an interior of the rear region <NUM> is substantially hollow. A plurality of knives <NUM> is provided at an inner surface of the rear region <NUM> to further process occlusion materials accumulated within the inner cavity <NUM>. More specifically, the knives cut further and transport the materials along the chamber to the hollow interior of the drive shaft. In an alternate background embodiment a processing unit, similar to the unit <NUM> illustrated in <FIG> and <FIG> is formed in the hollow interior of the rear region <NUM>. Such processing unit comprises a chamber having a drive shaft assembly with a conveying member rotationally positioned thereinside. The conveying member receives the occlusion material from the inner cavity <NUM>, cuts it further and transports the material along the chamber to the hollow interior of the drive shaft.

In one embodiment falling outside of the scope of the invention the guidewire <NUM> is formed as a hollow tube. The drive shaft <NUM> is also hollow. The particle-entrained blood can flow from the burr <NUM> through the ports <NUM> into the interior cavity48 and bore <NUM> and facing the guide wire <NUM> which is, at least partially, disposed within the hollowlumen32of the drive shaft connected to a suction or injection devices.

The hollow tube or central passage <NUM> of the guide wire <NUM> is used as a conduit for aspiration of occlusion debris. As illustrated, the guidewire <NUM> includes a plurality of apertures <NUM> along its distal end <NUM>. Use of such hollow guide wire enables a clinician to catch occlusion debris more efficiently. This is because, the apertures <NUM> allow to catch/collect debris right at the site, where they are produced in the surgical procedure and before being disbursed. The hollow guidewire <NUM> can be made from metal, or plastic, or graphene or any other material which meets requirement for guide wire and is not permutable for liquid that contains debris of occlusion or embolus.

The hollow/tubular guidewire <NUM> if needed, is also capable of delivering fluid/medication/coolant to a target location. With apertures <NUM> liquid/fluid/medication is allowed to leak from the hollow passage <NUM> out into the vasculature passageway. The location of discharge of liquid/medication/coolant from the tubular guide wire <NUM> can be controlled by controlling size of the apertures54 as well as the location thereof.

Further important functionality of the apertures <NUM> of the hollow guidewire <NUM> will become applicable when used in combination with the ports <NUM>.

A vacuum pump <NUM> (see <FIG>) creates a low-pressure zone at the proximal end <NUM> of the drive shaft and the hollow guidewire to aspirate debris of the occlusion or embolus in the blood vessel or body lumen produced by the device.

Controllable entry of the cutter/burr <NUM> into calcified occlusions/ obstructive lesion has to be assured for its predictable advancement. Thus, to facilitate such cutter advancement, the drive shaft <NUM> should be axially translatable with respect to guide wire <NUM>. In the current prior art practice evacuation of residual debris is often complicated and time-consuming technique/procedure. In current practice tools similar to the burr/cutter <NUM> are nudged into a calcified occlusions area during rotation and then retracted. This manipulation in the prior art procedure permits evacuation of residual debris and to reestablish local circulation before making another cutting cycle on the lesion. On the other hand, the ports <NUM> of the burr/cutter <NUM> establish a reliable communication between the burr cutting blades <NUM>, the hollow passage <NUM>, and the apertures <NUM> of the guidewire. In this manner residual debris is evacuated continuously during the procedure without the need for the complicated manipulations discussed above. Further, arrangements for catching occlusion debris are often located behind cutting burrs (either opening into debris collecting sheath or a debris catching basket). This approach leaves a high probability that some debris can escape into vasculature of a patient. Here, the debris is collected at an immediate area, where the debris accumulates due to the negative pressure suction through the multiple ports <NUM>.

Although the cutter/burr <NUM> has been discussed above for the removal of the occluding material from the blood vessels, it should be noted that application of the burr to many types of the intrabody surgery (as identified above) also forms a part of the disclosure. For example, in the ureteroscopy procedure, which treats and removes stones in the kidneys and ureters, burr <NUM> may be used in combination with the respective flexible scope. In the procedure, the doctor passes the scope with the burr through patient bladder and ureter into kidney. Use of the burr <NUM> may be especially applicable for larger stone removal and can be combined with other techniques and/or tools including energy-based devices to break stones up. Use of burr <NUM> may be also applicable in the ureteroscopy for the removal of polyps, tumors, or abnormal tissue from a urinary tract. Further application of burr <NUM> is in percutaneous nephrolithotomy or percutaneous nephrolithotripsy, combined with a small tube to reach the stone, the burr grinds/breaks the stone up. This action can be combined with the use of high-frequency sound waves, radio frequency or other energy-based devices. After the procedure, the pieces of a stone are vacuumed up and removed from the system with a suction arrangement.

<FIG> also illustrates an alternative feature of the burr/cutter <NUM>, wherein a center of the mass is not located in the center of the burr rotation, so as to create an orbital effect. More specifically the feature provides a mechanism <NUM> that moves the center of the mass away from the center of the burr rotation providing an operator with another controlling function. Thus, the center of mass is moved away from center of the burr rotation when operator wishes to drill a wider opening in the occlusion. On the other hand, the center of mass of the burr remains in the rotational center during other periods of surgery, thus preventing injuring to the blood vessel walls by the uncontrollable rotational forces that press the burr ablative surfaces to the vessel walls. As illustrated in <FIG>, the mechanism <NUM> consists of multiple or at least two weights initially located symmetrically relatively to the axis of the burr rotation, with one of the weights <NUM> being moved away from the rotational center. A pivoting arm <NUM> with the weight <NUM> pivots away from the connecting portion <NUM> when it is released by the operator. In the mechanism release and movement of the arm can be controlled in any conventional manner, mechanically, electrically, wirelessly, etc..

We are referring now to <FIG> illustrating further background embodiments provided for use in orthopedic and other types of surgery. Application of these surgical tools includes, but is not limited to drilling of the bones and surface ablation, scrubbing, or scraping of bones, ligaments, meniscus, cartilage etc. The bur/cutter <NUM>' of <FIG> is formed having conical head <NUM>' with a substantially hollow front cutting exterior region <NUM>' and a substantially solid rear region <NUM>'. The front region <NUM>'facing operation site is formed by longitudinal drilling sections24' extending along longitudinal axis of the cutter interconnected by transversely oriented cutting blade sections <NUM>. The drilling sections <NUM>' are positioned at an angle to each other defining in combination with the transverse cutting blades <NUM> a conically shaped grid formation culminating at a front tip <NUM>' of the head. The grid formation defines a plurality of ports <NUM>' between the drilling sections <NUM>' and the blades <NUM>'. Ports <NUM>' provide passage of debris from the exterior of cutter/burr to the internal cavity <NUM>'. As discussed above, conically shaped surfaces of the burr/cutter <NUM>' are used for drilling, surface ablation of the bones, etc. The bur/cutter <NUM>' of <FIG> is similar to that of <FIG> but is also provided with an exterior shield/cover <NUM>" preventing the materials/particles developed during the surgery from being dispersed, so as to be directed into the interior cavity <NUM>' for evacuation from the device by suction. The burr/cutter <NUM>" of <FIG> is formed having cylindrically-shaped head <NUM>" with a substantially hollow front cutting exterior region <NUM>" and a substantially solid rear region <NUM>". The front region <NUM>" is formed by substantial straight drilling sections24" interconnected by transversely oriented cutting blade sections <NUM>". The drilling sections <NUM>" define in combination with the transverse cutting blades <NUM>" a cylindrically shaped grid formation with a plurality of ports <NUM>". Optionally, a plurality of knifes <NUM>" can be provided at an inner surface of a hollow rear region <NUM>" to further process occlusion materials accumulated within the inner cavity <NUM>".

As illustrated in <FIG> control unit <NUM> houses a programmable logic controller <NUM> or microchip and power source <NUM> in operable communication to provide power and to control operation of various units of the system. Control unit <NUM> preferably comprises a base arranged so that the control unit may be stably supported on a work surface or a body surface during material removal operations. The control unit <NUM> also preferably incorporates control systems for actuating, adjusting, and providing system information concerning power, drive shaft rpm, drive shaft axial translation, aspiration, infusion, which displays reading of sensors located on the catheter and cutting instrument and the like. The control unit may include, but not limited to vacuum control unit, cutter advancer unit, guidewire control unit, cutter assembly drive control, and aspiration and infusion control unit. Control unit <NUM> also controls a block providing information concerning operating conditions and feedback from the material removal site to the operator. By means of a computer or microchip <NUM> the control unit <NUM> utilizes inputs received from multiple sensors <NUM> located at the burr/cutter <NUM> and/or other critical regions of the catheter assembly to continuously updated output to an operator including such operating parameters as temperature at the material removal site; cutter assembly rotation rate and/or advance rate; aspiration rate and/or volume; infusion rate and/or volume; and the like. Control unit <NUM> may additionally provide adjustable controls permitting the operator to control operating parameters of the cutter assembly and material removal operation.

As illustrated in <FIG>, the control unit <NUM> is provided to regulate the power source <NUM> for the optimum output level based on type and characteristics of the targeted occlusion (hard, soft, blood, etc.) and/or characteristics of the burr catheter (length, diameter, temperature, etc.). Characteristics of the control unit <NUM> may be adjusted by the operator or automatically based on inputs from the sensors <NUM>. Controlling various characteristics/parameters at the operation site are based on the information provided by sensors positioned at the distal end of the catheter and the burr, such as for example speed of rotation, temperature, etc. Such characteristics can be manually or automatically adjusted based on the signals and data received from the sensors <NUM> installed within the cutter/burr <NUM>.

Sensors <NUM> may emit and receive various types of signals (optical, electromagnetic, acoustical, capacitance measuring) that will change parameters depending on the composition or other physical properties of the occlusion and/or tissue surrounding occlusion and/or physical characteristics of the catheter itself, so as to allow the control unit <NUM> to calculate and generate proper signals controlling operation/speed of rotation, etc. of the burr <NUM>.

Sensors <NUM> located at the front portion <NUM> of the burr <NUM> can recognize (determine) the physical and chemical properties of the occlusion. A computer or microchip <NUM> associated with the control unit <NUM> receives and analyzes information/data obtained by the sensors <NUM> and generates signals to adjust parameters of the power source <NUM> to optimize the destruction of an occlusion in the blood vessel and/or to produce other desired effect on targeted tissue. As an example, control unit <NUM> analyzes information/data obtained by the sensors <NUM> and generates signals to adjust parameters of the power source <NUM> to optimize rotational speed, etc. of the burr <NUM>. This includes also applying different physical mechanisms of action to destroy occlusion. For example, the cutting arrangement can combine mechanical cutting tool and RF cutting electrodes which can be activated by the control unit <NUM> interchangeably based on the signal from the sensors describing the occlusion material characteristics which may require different tools for best removal.

The sensors <NUM> can detect the level of hardiness/calcification, water/moisture content, etc., within the material of an occlusion. As burr <NUM> passes through various areas of the occlusion, optimal levels of rotational speed, etc. can be achieved for each zone of treatment. For example, a higher speed of rotation can be provided for the destruction of calcinated occlusion having higher degree of hardiness. On the other hand, lower speed will be generated for the areas with softer occlusion materials for more effective blade cutting action.

Utilization of the cutting burr <NUM> is also accompanied by automatic target feedback, thermal feedback for example, to precisely control the speed of rotation, etc. This is needed to prevent damage to surrounding tissue. For this purpose, non-contact thermal detectors <NUM> can be provided. The output of the non-contact, thermal detectors <NUM> can be used to adjust the output of the power source <NUM> to maintain selected characteristics including temperature at the treatment site.

To effectively control the destruction of the occlusion, a condition of the entire artery body and/or the tissue surrounding the operation site is monitored by detector <NUM> adopted to detect irradiation reflected from such tissue. One of the functions of detector <NUM> is to control the effect of the drilling/ablation on the tissue surrounding the site. In every individual case a doctor sets specific rotational, etc. characteristics to produce the required effect. If a situation at the operation site becomes unfavorable, for example the temperature exceeds predetermined limits, the detector <NUM> generates a signal directed to the control unit <NUM>, which in turn produces a correcting signal to the power source <NUM> or to the control unit <NUM>.

The computer or microchip <NUM> of the control unit <NUM> receives and analyzes the information obtained by the detector <NUM> and to generate a control signal to adjust parameters of the power source <NUM> in such a way as to optimize the destruction of an occlusion in the blood vessel or other desired effect on targeted soft tissue.

Alternatively, the control signal generated by the thermal detector <NUM> energizes the cooling arrangement (see above) to directly or indirectly lower/adjust temperature at the site. This is necessary to exclude the possibility of damaging an adjacent tissue. The detector <NUM> and the sensors <NUM> can be made utilizing a wide variety of photoelements, photoresistors, photodiodes and similar devices. Overheating may also occur in the length of the catheter particularly where the catheter is bent to a sharp angle thus installing temperature sensors along the length of the catheter may improve safety profile of the device.

As discussed above, frictional forces resulted from the engagement/drilling between the burr <NUM> and the material of the occlusion, as well as other factors may result in temperature elevation of the surrounding tissue. In the disclosed device, the temperature elevation occurs controllably without causing irreversible thermal damage to the surrounding tissue of the arteries. Control unit <NUM> adjusts the energy to maintain a pre-selected target temperature at the site. To maximize patient safety, an optional continuous or pulsed cooling device can be provided to deliver a coolant from the infusion material storage <NUM> by means of the infusion pump <NUM> through the hollow guide wire <NUM> to the operation site during or after surgical procedure.

The diagram of <FIG> schematically depicts a system according to a background system that may be connected to the cutter <NUM> to evacuate the ablated or cored bodily material from a subject's vascular system using various embodiments of the cutter/ burr <NUM>. The vacuum pump <NUM> provided at the proximal end <NUM> of the drive shaft creates low-pressure zone resulted in suction pressure within the lumen or hollow inner space <NUM> of the drive shaft and the passage <NUM> of the guide wire <NUM> to evacuate cut and/or ablated bodily material directly from the operating site in the vascular system.

Alternatively, the vacuum pump <NUM> is interconnected to a pulse modulator <NUM>, the actuation of which creates one or more pressure differentials to the aspiration system. Accordingly, using the pulse modulator <NUM>, rather than creating a constant suction pressure within the system to evacuate cut and/or ablated bodily material from a subject's vascular system, the aspiration system disclosed applies alternative pressure(s), thereby creating pulses of suction pressure within the lumen. Utilizing a series of constant and/or varying pressure pulses is potentially beneficial in aspirating bodily material, particularly when aspirating larger cylindrically looking core or plug like shapes of bodily material.

Aspirated liquid and/or particles from an area near the distal end of the tool are accumulated and stored in the disposable debris storage <NUM>. A filter <NUM> can be also provided upstream of system for filtering debris and aspirated bodily material and also for providing visual feedback to a user related to the type, quantity, and flow rate of material being removed from a patient. The debris container <NUM> may be in fluid communications with the vacuum pump <NUM> and may include one or more known devices for collecting and filtering materials removed from a patient. The container <NUM> may have transparent sidewalls for providing visual feedback to a user regarding flow-rate, content, coloration, etc. Those of skill in the art will appreciate that various types of collection containers may be used. The collection container <NUM> and/or filter <NUM> may also comprise one or more custom filter features with various mesh sizes, capacities, etc. based on the specific application.

The distal end <NUM> of the hollow guide wire <NUM> functioning as a suction conduit can be made of a variety of flexible or rigid materials or a combination of both, such as metal or plastics. Still further, the distal end <NUM> of the guide wire formed as a suction conduit can be made of a material different from the body of the hollow guidewire. For example, one might want to make the distal end <NUM> with a more heat-resistant material to withstand high energy directed to it. It may also be desirable to use a more impact-resistant material to withstand the initial impact from the solid particles drawn by the suction force.

Referring now to <FIG>, showing an expanded/working position of a sleeve <NUM> provided for slidable motion along an exterior of the catheter according to another teaching falling outside of the scope of the invention. The distal end of catheter assembly <NUM> is provided with the sliding sleeve <NUM> having an activating mechanism <NUM> provided for controllable movement of the sleeve back and forth along the catheter exterior. The activating mechanism <NUM> is spring controlled. However, the activating mechanism <NUM> can be energized/actuated in any conventional manner, such as for example electrical, pneumatic, etc. mechanisms are contemplated. The front/distal end <NUM> of the sleeve <NUM> is designed to establish a tight contact with the occlusion. For example, distal end <NUM> can be made of a resilient material capable of adopting to evolving configuration of the external part of the occlusion during the procedure. Therefore, catching the occlusion debris and channeling them into the hollow tubular passage <NUM> for aspiration has been enhanced. As illustrated, in the working position the sleeve <NUM> extends outwardly from the exterior of the catheter <NUM>. In this arrangement the diameter of the outer periphery at the distal end of the catheter is slightly increased. In the contracted position the sleeve60 is positioned along the exterior surface of the catheter.

In another example, illustrated in <FIG>, a circumferential recess <NUM> is formed within the distal end of the catheter body having the depth and length corresponding to the respective dimensions of the sleeve <NUM>. The exterior surface of the sleeve is in flash with the exterior surface of the catheter. Prior to the catheter's placement through the blood vessel lumen to the operation site, the sleeve <NUM> is pressed inwardly in the direction of the proximal end to overcome resistance of the activating mechanism <NUM>. As a result, the sleeve <NUM> is submerged within circumferential recess <NUM>. In this locked position the exterior of the sleeve <NUM> is in flash with the exterior of the catheter. Upon delivery and proper positioning at the site, the activating mechanism <NUM> is released-unlocked and the sleeve <NUM> is moved to the expanded working position to provide a tighter contact between the distal end <NUM> of the sleeve <NUM> and the occlusion.

Turning now to <FIG> showing an alternate background example, which provides further increased ability of the sleeve to accommodate randomly shaped occlusions for optimally sealing the cutting/drilling site. As illustrated in <FIG>, longitudinal slits <NUM> are circumferentially arranged within the sleeve body forming a plurality of segments. The slits <NUM> extend inwardly from the distal end of the sleeve to separate the sleeve body into a plurality of segments <NUM>. In one example, the front area of the segments <NUM> can be curved and/or formed from a resilient material to further improve engagement with the occlusion. Any reasonable number and configuration of the slits and/or segments are plausible.

Turning now to <FIG> showing another background example of a sleeve assembly <NUM> provided to further increase ability of the sleeve to augment randomly shaped occlusion for optimally sealing the cutting/drilling site to maximize catching debris of the destroyed occlusion. Longitudinal slits are circumferentially arranged within the sleeve body forming a plurality of segments. Such segments can longitudinally move independently of each other to optimally adapt to the random shapes of possible occlusion deposits. Assembly <NUM> consists of an external base <NUM> formed by a cylindrical side wall <NUM> and a rear wall <NUM>, so that a hollow inner cavity <NUM> is defined therebetween. A plurality of separated from each other engaging segments <NUM> are positioned in the inner cavity <NUM> for independent slidable movement along a longitudinal axis the assembly. Any reasonable number of the segments can be symmetrically arranged within the cavity. Each engaging segment consists of at least a front part <NUM> adapted for engagement with an occlusion and a rear part <NUM> adapted for movement within the inner cavity129. A biasing member or a spring <NUM> is positioned between the rear part <NUM> of each segment and the rear wall <NUM> of the base. In use, upon the sleeve approaching the occlusion, the front parts of each segment which is pressed by the biasing member <NUM>, engages the respective area of the occlusion having a specific configuration. This occurs independently from other segments. The front part <NUM> of each segment is formed to provide tight contact with a respective area of the occlusion. In one example, the front part <NUM> is made of a resilient material capable of adapting to evolving configuration of the respective part of the occlusion. Therefore, the sleeve assembly <NUM> provides an improved tighter contact between the front parts of the segments and the occlusion during the procedure.

<FIG> illustrate yet another background example which combines application of the above-discussed burr/cutter <NUM> with the sliding sleeve <NUM> movably positioned at the connecting element <NUM> of the burr. The stop member <NUM> is provided at the proximal end of connecting element <NUM>. As illustrated, the sleeve <NUM> is arranged for a movement along the connecting element <NUM>. The advancement of the sleeve in the proximal direction is limited by stop <NUM>. The hollow interior of the sleeve defines an interior space <NUM> which accommodates the burr <NUM> and serves as its housing. As illustrated in <FIG>, in the initial position on the connecting element burr <NUM> is positioned within chamber <NUM>, so that the wall of the sleeve extends over the burr exterior. This position of the sleeve is locked by a key <NUM>. This arrangement allows for safe travel of the burr <NUM> covered by the sleeve <NUM> through a blood vessel to an occlusion area. When the burr covered by the sleeve reaches the occlusion, rotation of the burr by drive shaft is initiated. The torque moment at the beginning of the rotation breaks the key <NUM> causing disengagement of the burr and sleeve. Thus, independent operation of the bur and the sleeve is initiated. As illustrated in <FIG> rotating burr <NUM> drills the occlusion. On the other hand, the sleeve becomes independently slidable by means of the loaded spring arrangement <NUM> which pushes the sleeve <NUM> toward the occlusion to establish a contact therebetween, to further maximize catching of the cut debris into the internal hollow space <NUM> of the burr.

An abrasive or cutting material is bonded or by any other conventional means attached to the distal end <NUM> of the sleeve, forming an auxiliary cutting region. In an alternateexample, a cutting element or a cutting edge can be formed at the distal end <NUM> instead of the abrasive material. In this manner this assembly is provided with two cutting regions, including the burr/cutter <NUM> and the auxiliary cutting region at the distal end <NUM>.

To drill away the occlusion the rotating burr <NUM> is moved by the advancing catheter in the distal direction. After that rotation motion of the sleeve <NUM> is initiated. In this process a major central portion of the occlusion is cut or drilled away by the cutting burr <NUM>. Furthermore, as illustrated in <FIG>, a portion of the occlusion along inner walls of the blood vessel or lumen is removed or cut away by rotation of the auxiliary cutting region provided at the distal end <NUM> of the rotating sleeve. Thus, this arrangement enables a practitioner to eliminate or cut away the entire occlusion in one procedural step. In the prior art however, the portion of the occlusion disposed along the inner walls of the blood vessel or lumen is not removed due to relatively small outer diameter of the burr.

During the process of inserting the catheter through the blood vessels to the point of occlusion and during the cutting procedure, walls of the sleeve <NUM> isolate the burr <NUM> from the blood vessel walls <NUM>. Thus, a risk of accidental perforation of the blood vessel walls <NUM> or any other adjacent tissue during the procedure is minimized. The interior space <NUM> of the sleeve creates a conduit which accommodates materials cut during the procedure and improves the flow of various fluids during aspiration and/or infusion.

Among essential functions of the sleeve assembly illustrated in <FIG> is to form an enhanced engagement with the occlusion. Thus, that the distal end of the sleeve provides, upon engagement with occlusion an isolation of and a potential vacuum within space <NUM>, having the burr <NUM> being positioned thereinside. Upon rotational/drilling motion of the burr, created debris or cut materials are accumulated/disposed within the inner space <NUM> and evacuated by suction through the plurality of ports <NUM> into the internal hollow space <NUM> of the burr. This example also provides the burr - sleeve assembly of various sizes, so as to enable a practitioner to more precisely accommodate specifics or sizes of each vessel or lumen being operated upon. Thus, the larger size is accommodated by the sleeve <NUM> having a larger diameter, whereas smaller diameter sleeves are provided for smaller size vessels. This feature is especially important when a close contact between the exterior of the sleeve and interior of the vessel is needed for the removal of parts of the occlusion disposed adjacent the vessel's interior surfaces. During the stage of inserting the catheter into the vessel and through its movement through vascularity to the surgery site (occlusion) the sleeve <NUM> is locked in such a way that it surrounds the burr/cutting surfaces thus protecting the internal walls of the blood vessels from being injured by the burr cutting surfaces and therefore minimizing risk of in vessel unwanted growth of soft tissue as a reaction to the wounds caused by such cutting surfaces being pushed through the vessels to the occlusion site. When burr/cutting arrangement reaches the occlusion site the sleeve <NUM> is released from the locked position with start of the shaft rotation.

It should be noted that application of the slidable sleeve <NUM> is not limited to the removal of the occluding material from the blood vessels. The sleeve <NUM> can be used in many types of the intrabody surgery (as identified above). For example, it can be used in ureteroscopy procedure, which treats and removes stones in the kidneys and ureters. The sleeve <NUM> may be used in combination with the flexible scope, which is passed through patient bladder and ureter to provide an enhanced contact with kidney. Use of the sleeve <NUM> facilitates larger stone removal, combined with RF cutting device, which passes through the scope to break stones up. Another example is use of the movable sleeve <NUM> in the ureteroscopy for the removal of polyps, tumors, or abnormal tissue from a urinary tract in orthopedic or general surgery. Similar to the above discussed applications, the sleeve <NUM> can be used in percutaneous nephrolithotomy or percutaneous nephrolithotripsy, combined with a small tube to reach the stone and break stone up with high-frequency sound waves or RF cutting device. The broken pieces are vacuumed up and removed from the system by a suction arrangement of the invention.

Although the assembly combining the burr/cutter <NUM> with the sliding sleeve <NUM> has been discussed above, it should be noted that use of the cutter/burr with other type of protective devices is also possible. For example, an assembly where the burr/cutter <NUM> is combined with the sleeve arrangement illustrated in <FIG> is also contemplated.

In a preferred embodiment of the invention illustrated in <FIG>, a processing unit <NUM> with a rotatable blade assembly or cutting element85 is provided at the distal end of the drive shaft <NUM> to cut and macerate the occlusion (embolus) and to evacuate cut materials away from the site. The rotatable blade assembly <NUM> includes a hub and a plurality of blades arranged at the hub. Each blade is formed having a leading cutting edge and a trailing edge and extends in a plane generally perpendicular to the axis of rotation.

The processing unit <NUM> comprises a chamber <NUM> having a drive shaft assembly <NUM> with a conveying member86rotationally positioned thereinside. The conveying member <NUM> receives the occlusion material cut by the cutting element <NUM> and transports the material along the chamber <NUM>.

The drive shaft assembly <NUM> both transports cut tissue/material within the processing unit <NUM> and drives rotation of the cutting element <NUM>. In other embodiments the drive shaft <NUM> may transport the cut tissue proximally within the processing unit <NUM> but may not drive rotation of a cutting element <NUM>. <FIG> shows that the drive shaft assembly <NUM> is attached to the cutting element <NUM>.

The drive shaft <NUM> is generally cylindrical and may comprise a solid tube or a hollow tube. The drive shaft with the conveying member <NUM> is manufactured to be flexible enough to facilitate navigation through tortuous vessel anatomy and strong enough to withstand the stresses encountered by high-speed rotation, transmission of torque through the driveshaft to the cutter <NUM> at the distal tip of the processing unit <NUM>, and transport occlusion material. The conveying member <NUM> may be a separate element which is attached or affixed in some manner to a substantially cylindrical drive shaft. Alternatively, the drive shaft <NUM> and the conveying member <NUM> may be formed as a single unitary element.

The drive shaft <NUM> is formed having a central lumen <NUM>, which is used to deliver the guidewire <NUM>, and may be coated with a lubricious material to avoid undesirable binding with the guidewire. Central lumen <NUM> of drive shaft <NUM> may also be used to deliver fluids to the operative site simultaneously with or in place of the guidewire.

In one embodiment of the invention plate <NUM> having a plurality of holes <NUM> passing from one face of the plate to the other is positioned within the chamber <NUM> transversely to the longitudinal axis thereof. In this manner, the occlusion material initially cut by the cutting member <NUM> is delivered by the conveying member <NUM> to the chamber <NUM> for further processing by passing through the plurality of holes 97of the plate <NUM>. The receiving chamber <NUM> along with the shaft <NUM> with the conveying member <NUM>, and the optional plate <NUM> forms a first processing section <NUM> of the unit <NUM>. Optionally it can be a second chamber <NUM>'. Occlusion material from chambers <NUM>/<NUM>' is pushed by the conveying member <NUM> to then space <NUM> through which the debris is vacuumed into the disposable storage located in the control unit.

The conveying member <NUM> may be an auger type system or an Archimedes-type screw that conveys the debris and cut material generated during the procedure away from the operative site. The conveying member <NUM> has raised surfaces or blades that drive materials away from the operative site. Blades of the conveying member <NUM> may extend up to a full diameter of the internal chamber <NUM> or a part of it.

Debris can be evacuated outside the body by the conveying member <NUM> action along the length of the catheter and with or without supplement of the vacuum pump connected to the catheter. Alternatively, the debris may accumulate in a reservoir within the device.

Optionally, a plurality of generally equally spaced ridges <NUM>, which can be collapsible in nature, are provided, extending from an inner wall <NUM> of the chamber. Ridges <NUM> tend to provide sufficient clearance about the conveying member <NUM>. In this manner, initially processed occlusion materials can be propelled through the processing unit <NUM> without development of back pressure due to clogging in the assembly. Ridges <NUM> are aligned to increase material throughput rate by channeling material towards the proximal end of unit <NUM>.

As further illustrated in <FIG>, optionally the tool of the invention can be provided with a second processing section <NUM>. The second section <NUM> comprises a second chamber <NUM>' with a second drive shaft <NUM>'section having a conveying member <NUM>' with a second pitch generally somewhat smaller than the pitch of the first conveying member <NUM>. The first and second conveying members are coaxially arranged and formed with longitudinally extending apertures used to accommodate, among other functions the hollow guidewire of the invention. The second section <NUM> can be optionally provided with a second plate <NUM>' having a second plurality of holes <NUM>' passing therethrough from one face thereof to the other. The holes <NUM>'of the second plate <NUM>'may be smaller than the holes of the first plurality of holes <NUM>. In this manner, as previously discussed, the occlusion materials are initially processed by passage through the first plurality of holes <NUM> under the impetus of the first conveying member <NUM>. Then, such initially processed material is further processed to a smaller size by passage through the second plurality of holes <NUM>' under the impetus of the second conveying member <NUM>'. The first and second conveying members can be formed as one unitary continuous structure or as two independent units. The debris is pushed by conveying member <NUM>' through the opening <NUM>' into space <NUM> connected with the vacuum in the control unit.

The second processing chamber can be employed in certain situations, for example, where highly calcified occlusion is encountered. In this instance, the material exiting the first plurality of holes can be in the form of relatively coarse agglomerations. Such material is then picked up and propelled by the second conveying member, to help to guide the material towards the second plate. As the cut material passes through the second plurality of holes of the second plate, further reduction of sizes of the occlusion particles takes place.

As illustrated in <FIG> processing unit <NUM> is provided with the sleeve <NUM> slidably arranged at the exterior part of the catheter. In the illustrated expanded position, the sleeve <NUM> extends outwardly from the distal end of unit <NUM>. The hollow interior of the sleeve forms an interior space <NUM> that serves as a housing for the cutting element <NUM>. An area of connection between the drive shaft and the cutting element <NUM> is also accommodated in space <NUM>. When the sleeve <NUM> is retracted in the proximal direction, the cutting element <NUM> is exposed.

In use when the sleeve <NUM> is in the expanded working position, the distal end <NUM> of the sleeve <NUM> engages the occlusion, then the cutting element <NUM> by the drive shaft is delivered through the interior space <NUM> to the operation site. The interior space <NUM> also creates a conduit which accommodates materials cut during the procedure and to improve the flow of various fluids during aspiration and/or infusion. In this embodiment the cutting element <NUM> is precisely delivered to the occlusion. Further, the walls of the sleeve <NUM> isolate the cutting element <NUM> from inner surfaces of the blood vessel walls to minimize the risk of accidental perforation/damage of the blood vessel walls.

In the operation of the processing unit <NUM>, initially the occlusion material cut by the cutting element <NUM> is processed and fed into the chamber <NUM>. In the embodiment where plate <NUM> is provided, the drive shaft assembly <NUM> having a conveying member <NUM> propels the cut occlusion material towards and through the holes <NUM>. Thus, the size of the initially cut occlusion materials is reduced to become more adaptable for suction, collection and disposal as previously discussed. To further reduce the size of the cut occlusion materials, the second processing chamber <NUM>' may be utilized in the above-discussed manner.

Application of processing unit <NUM> combined with the cutting element <NUM> to many types of intrabody surgery (as identified above) also forms a part of the invention. For example, in ureteroscopy procedure, which treats and removes stones in the kidneys and ureters, the processing unit <NUM> may be used in combination with the respective flexible scope. Use of the processing unit <NUM> is also applicable for larger stone removal, combined with RF cutting device, which passes through the scope to break stones up. Further, in the ureteroscopy the processing unit <NUM> can be used for the removal of polyps, tumors or abnormal tissue from a urinary tract. The processing unit <NUM> including the cutting element <NUM> is also usable in percutaneous nephrolithotomy or percutaneous nephrolithotripsy, combined with a small tube to reach the stone and break stone up with high-frequency sound waves or RF cutting device. Further, the processing unit <NUM> can be used in intrabody, laparoscopic and endoscopic orthopedic surgeries including but not limited to spine surgery, knee, or hip replacement and similar. The processing unit <NUM> can be used for safe and effective removal of any soft tissue. After the procedure, the pieces are vacuumed up with a suction arrangement disclosed.

Turning now to <FIG> showing a processing unit <NUM> provided with a cutting assembly <NUM> at the distal end of the drive shaft <NUM>. Theassembly <NUM> is formed with a hub160, a plurality of blades <NUM> arranged at an outer band <NUM> arranged at outer peripheries of the blades <NUM>. In one embodiment, the hub, the blades, and the outer band can be integrally formed. Each blade <NUM> is formed having a leading cutting edge <NUM> and a trailing edge <NUM>, which extend in a plane generally perpendicular to axis of rotation. The outer band <NUM> has a front/distal area <NUM> facing the occlusion and a rear/proximal area. An abrasive cutting material is bonded or by any other conventional means attached to the distal area, forming an auxiliary cutting region <NUM>. In the alternative, a cutting element or edge can be formed at the front area <NUM> of the outer band. Thus, the cutting assembly <NUM> is formed with two cutting regions, including the primary cutting region defined by the leading cutting edges <NUM> of the blades <NUM> and the auxiliary cutting region <NUM> defined the front area <NUM> of the outer band. In use, upon approaching the occlusion, the leading edges <NUM> of the primary cutting region remove or cut away a central area of the occlusion. On the other hand, tissues of the occlusion at the inner walls of the blood vessel are eliminated or cut away by the auxiliary cutting region <NUM>. In the prior art procedures due to smaller outside diameter of the cutting tools relative to the inner diameter of the blood vessels and other reasons, such occlusion tissue often remains unremoved. Thus, application of the cutting assembly <NUM> of this embodiment enables a practitioner to eliminate or cut away the entire occlusion in one procedural step. This embodiment can be used for cutting soft occlusions tissues and is particularly applicable in stent restenosis procedures.

Similar to <FIG>, the embodiment of <FIG> the processing unit <NUM> includes a chamber <NUM> with the drive shaft <NUM> provided with the conveying member <NUM>. The drive shaft and the conveying member transport removed or cut tissue in the processing unit <NUM> and drive rotation of the cutting assembly <NUM>. As illustrated in <FIG>, the catheter is formed with an exterior sheath/ to be shown/ spaced from an inner hollow tube receiving the drive shaft. The drive shaft <NUM> is formed having the central lumen <NUM> used to deliver the guidewire <NUM> and may also be used to deliver fluids to the operative site. To facilitate rotation of the drive shaft and the cutting assembly <NUM>, the distal end/to be shown/ of the processing unit <NUM> is separated from the cutting assembly <NUM> by a gap/to be shown/. Also, as illustrated in <FIG>, the distal end can be flared. Furthermore, a lubricant can be delivered through the space separating the interior of the hollow tube and the drive shaft. The walls of the housing <NUM> may optionally expand to a higher diameter comparing with the average diameter of the catheter to accommodate a wider blade assembly <NUM> to optimally ablate occlusions in a larger diameter vessel.

The occlusion material cut by the cutting assembly <NUM> is delivered by the conveying member <NUM> to the chamber <NUM> for further processing, as previously discussed in the embodiment of <FIG>. Then debris of processed cut material are evacuated through the space separating the exterior sheath from the inner tube with or without supplement of the vacuum pump connected to the catheter. Alternatively, the debris may accumulate in a reservoir within the device.

Turning now to <FIG> illustrating another background example, wherein a source (generator) of ultrasound energy is disposed at the proximal end of the catheter. In the illustrated example the source is in the form of a pair of spaced from each other ultrasound waive generators provided to generate ultrasound waves/beams focused on a specific area in the vicinity of the proximal end of the catheter. In use the proximal end is delivered to the occlusion, so that the ultrasound beams are focused to an area within the body of the occlusion for selective destruction of the occlusion tissue. Since the focus is spaced from the surrounding tissue, the risk of collateral damage to the surrounding blood vessels walls is minimized. Although a pair of cooperating ultrasound generators is shown, it should be appreciated however that the distal end of the catheter can be provided with any reasonable number of cooperating ultrasound generators.

As illustrated in <FIG>, a distal end <NUM> of catheter <NUM> is formed having a convex-shaped region <NUM> with one pair of the symmetrically arranged ultrasound energy generators <NUM> and <NUM>. The convex-shaped region <NUM> reflects the energy emitted from the ultrasound generators and the beams <NUM> of the ultrasound energy are optimally focused at a specific/predetermined area within the body of the occlusion for a selective destruction of tissue. The focus of the beams <NUM> is disposed along the longitudinal axis A-A of the catheter and spaced from the distal end <NUM>.

Optionally the distal end <NUM> of the catheter is made from a resilient material and the convex-shaped region <NUM> forms a suction cup, to further improve engagement between the distal end and the occlusion. This arrangement prevents spreading and facilitates catching of the debris. In addition, ultrasound energy detectors and/or other sensors <NUM>, including but not limited to the temperature sensor, can be provided at the distal end <NUM> to control operation of ultrasound energy generators <NUM> and <NUM>. Sensors/detectors <NUM> detect data related physical properties and chemical composition of the occlusion and transmit such data to the control unit. As previously discussed regarding <FIG>, the computer or microchip <NUM> of the control unit <NUM> receives and analyzes the information obtained by the sensors/detectors <NUM> and generates a control signal to adjust functionality of the ultrasound energy generators <NUM> and <NUM>, to optimize the destruction of an occlusion and produce other desired effects on targeted soft tissue.

As illustrated in <FIG> the convex-shaped region <NUM> provided with the ultrasound energy generators <NUM>, <NUM> can be used with the sleeve <NUM> slidably arranged at the exterior area of the catheter114. In the illustrated expanded position, the hollow interior space <NUM> of the sleeve <NUM> serves as a housing for the convex-shaped region <NUM> including the ultrasound energy generators <NUM> and <NUM>. In use the sleeve <NUM> is placed into the expanded, working position, and the distal end of the catheter with the ultrasound energy generators are delivered through the interior space <NUM> to the close proximity of the occlusion. In this manner, the ultrasound beams <NUM> are optimally focused at a specific area at the body of the occlusion for a selective destruction of the tissue. The interior space <NUM> of the sleeve <NUM> forms a conduit which accommodates materials cut during the procedure and improves the flow of various fluids during aspiration and/or infusion associated with use of the catheter. The convex-shaped region <NUM> with the ultrasound energy generators <NUM>, <NUM> are precisely delivered to the occlusion, and the walls of the sleeve further isolate the generators <NUM>, <NUM> from inner surfaces of the blood vessel walls <NUM>, minimizing the risk of their accidental damage and/or perforation.

Turning now to <FIG> illustrating electro-surgical tool <NUM> according to a further background example. In this example electro-surgical effects of ablation and resection are accomplished by applying a radio frequency (RF)current to the tissue through active electrodes (+)<NUM>, from which the RF current flows to a ground or return (-) electrodes <NUM>. As it passes through tissue from the active electrodes to the ground electrodes, the RF current cuts and/or coagulates the tissue, depending on power and wavelength combinations. A flexible elongated hollow tubular body <NUM> is usually flexible and constructed of an electrically insulative material. Any of a number of polymeric or plastic materials may be employed for this purpose. The distal end <NUM> of the tool includes a plurality of the active electrodes and associated ground electrodes. A source (generator) of RF (radio frequency) energy (not shown) is disposed at the proximal end <NUM> of the tool or proximal end of the catheter in the control unit - power source. As illustrated in <FIG>, in one application the catheter includes multiple electric wire conductors <NUM> longitudinally extending within a hollow interior of the body <NUM> to deliver electric current/voltage to the RF electrodes <NUM>, <NUM> provided at the distal end.

The ground electrodes (-) <NUM> are positioned close enough to the active (+) electrodes <NUM>, so that the RF current flows a short distance. In this manner, loss of RF current by dissipation to the tissue and/or conductive irrigation fluids is reduced, and the desired effect or cutting performance of the tool <NUM> is not significantly degraded. In the bipolar instruments disclosed, the active electrodes <NUM> and the associated return electrodes <NUM> are disposed in close proximity to one another. So that there is less likelihood of current flow to tissues other than intended tissue being operated upon. Well-controlled bipolar RF energy delivery of the apparatus of this embodiment is preferred when ablating thinner or more delicate areas of tissue or when there is concern of possible collateral damage to target or non-target tissue.

As shown in <FIG>, the wire conductors <NUM> which deliver RF current to the electrodes are located within the interior cavity of the tubular body. The wire conductors and electrodes are designed so that they do not take up a significant amount of the interior volume of the tubular body <NUM> and that the individual electrodes/wires do not interfere with each other. Open spaces formed within the catheter body between the wires and/or electrodes are used to evacuate ablated bodily material produced during the procedure. The evacuation can be accomplished, for example by a vacuum pump provided at the proximal end of the system creating allow-pressure zone resulted in suction pressure within the hollow inner space of the catheter, so that ablated bodily material directly removed from the operating site.

In an alternate example, as illustrated in <FIG> electro-surgical tool <NUM> may also be constructed as a bipolar RF device with a single return/passive electrode202 which is associated with a plurality of active electrodes disposed at the distal end of the body. The single passive electrode <NUM> is positioned at the distal end <NUM> of the catheter body in closely spaced relationship relative to the active electrodes. In one example the single return/passive electrode <NUM> (see <FIG>) may be a unitary conductive ring positioned at the distal end of the catheter, completely of partially surrounding the distal end, with a surface area being substantially larger than that of any of the active delivery electrodes <NUM>. It should be noted however that other shapes/forms/designs of the passive electrode are within the scope of the disclosure.

In an alternate background example (see <FIG> the conductive ring at the distal end of the catheter can be separated into a plurality of segments <NUM> forming multiplicity of return/passive electrodes <NUM> juxtaposed with individual active electrodes <NUM>. These electrodes are in the form of metal sections/inserts electrically insulated from each other and completely of partially surrounding the distal end periphery. In this manner multiple bipolar tissue cutting segments are formed through entire cross-section of the tool <NUM>.

The electrodes are positioned at the distal end, so that the electric current alternating between electrodes destroys the occlusion in contact with the electrodes. Because RF energy is delivered by means of electric current alternating between electrodes spaced/separated from inner areas of the blood vessel walls, application of RF technology provides higher safety compared to other methods. Therefore, the possibility of damaging adjacent walls/tissues of blood vessels is minimized.

In a manner previously discussed, detector and/or sensor <NUM> can be provided at the distal end of the catheter for determining physical and chemical composition of the occlusion and by means of the computer or microchip of the control unit to adjust functionality of RF emitters.

The background examples of <FIG> were discussed with the source (generator) of ultrasound energy being disposed at the proximal end of the catheter. However, use of other energy generators is also within the scope of the disclosure. For example, the catheter can be provided with a cavitation source disposed at the distal end to deliver cavitation waves to be used in intrabody surgery. In use the catheter passes through/positioned within the blood vessels (veins or arteries), so that such waves destroy or affect a soft tissue or an organ in a certain desirable way through mechanically or chemical-mechanical properties and/or forces. Outlets emitting cavitation energy can be added to the distal end of an existing catheter.

According to one background example the cavitation energy outlets are positioned on the outer diameter of the catheter tip and disposed at the longitudinal axis passing through the catheter. This facilitates focusing the cavitation waves at the central area of the occlusion. In this arrangement while the occlusions are destroyed, the risk of damage to the blood vessel walls is substantially reduced or minimized.

As previously discussed, detector and/or sensor are provided at the distal end of the catheter capable determining physical and chemical composition of the occlusion and by means of the computer or microchip of the control unit to adjust performance of the cavitation energy outlets. As illustrated on <FIG> a distal end <NUM> of a guidewire <NUM> can include a bend or curved portion which facilitates navigation of the guidewire in vasculature. Although various angles of inclination of the distal end to the remaining part of the guide wire are contemplated, here, the distal end <NUM> is inclined at about <NUM>-degree angle.

During the atherectomy procedure a guide wire is first installed into the vein or artery from the entre point of the patient body till the targeted occluded area of the targeted blood vessel. Such guidewire is designed to be thin and easy to pass within the blood vasculature. However, the longitudinal movement of the guidewire within the vessel is executed by the surgeon by pushing the guidewire forward along the blood vessel. For this movement to occur the guidewire must have certain stiffness which keeps it straight and prevent its coiling within the blood vessel. However, such stiffness in turn complicates the guidewire passing through the difficult vasculature with close to <NUM> degree or abuse angle of vessel curvature. Turning now to <FIG> showing that the very end section of guidewire <NUM> can be bent to an optimum angle which may facilitate the guidewire passing through difficult angle vasculature. The surgeon can combine pushing of guidewire and rotating it so that the bent end of the guide wire may have a higher chance to slide into the difficult angle vessel while the straight end guidewire would just stop by pushing into the vessel wall. <FIG> shows a prior art straight guidewire inserted through the bore or lumen of a blood vessel <NUM> to cause a stop at the vessel wall making a sharp <NUM>-degree turn. The bent end guidewire is utilized to facilitate passing the sharp bend vascularity by providing an optional side direction for guide wire pushed forward by the surgeon. <FIG> illustrates a specific application of this feature, wherein <NUM>-degree bended tip of the guidewire <NUM> is successfully pushed through by a main straight portion of the guidewire <NUM> through a <NUM> degree turn in vasculature.

Claim 1:
A catheter device (<NUM>) for intrabody surgery, comprising:
a processing unit (<NUM>) with a rotatable blade assembly or cutting element (<NUM>) at the distal end of a drive shaft (<NUM>), the drive shaft (<NUM>) being provided with a conveying member (<NUM>),
the rotatable blade assembly or cutting element (<NUM>) including a hub and a plurality of blades arranged at the hub, each blade being formed having a leading cutting edge and a trailing cutting edge and extending in a plane generally perpendicular to the axis of rotation,
the drive shaft (<NUM>) passing through an inner area of the processing unit (<NUM>), the inner area formed with a chamber (<NUM>) with a conveying member (<NUM>) rotationally positioned thereinside, the conveying member (<NUM>) having raised surfaces extending outwardly within the chamber (<NUM>),
a sleeve (<NUM>) slidably arranged at the exterior part of the catheter (<NUM>) and movable along the outer area of the processing unit (<NUM>) between expanded and retracted positions, the sleeve (<NUM>) having an outer wall with a front edge (<NUM>) and defining an interior hollow space (<NUM>), at least a part of the cutting element (<NUM>) located within the interior hollow space, such that when the sleeve (<NUM>) is retracted in the proximal direction, the cutting element (<NUM>) is exposed whereas when the sleeve (<NUM>) is in the expanded position the cutting element is located within the interior hollow space
a cutting region defined by the leading edge of the plurality of blades within the cutting element (<NUM>); and
wherein, in use, upon approaching an occlusion, the blades of the cutting region remove a central area of the occlusion.