A stencil of sheet metal for enabling solder paste to be applied to circuit boards includes a main body portion and opposite side regions which are apertured so as to be more flexible than the main body portion, and so as to enable these opposite side regions to be bent without kinking or other deformation during tensioning. The invention further includes an apparatus for enabling solder paste to be applied to a circuit board by a stenciling process, the apparatus including a stencil as described together with a support therefor, the stencil being attached to the support and being detachable therefrom. The side regions of the stencil are flexed for attachment to the support, so that the interconnection between the support and the stencil does not project beneath a lowermost planar surface of the stencil.

1. Field of the Invention
The present invention relates to an improved stencil or mask for use in applying solder paste on to circuit boards and to a support frame therefor.
2. Description of Related Art
It is known to produce electric circuit boards with solder connections for components, such as integrated circuit chips, by applying a solder paste to the circuit board by means very similar to screen printing. In one such known printing arrangement, a solder stencil or mask comprises a thin but still relatively stiff sheet of stainless steel or brass in which fine lines or apertures for the passage of solder paste have been formed, for example, by etching or laser cutting. The metal sheet is bonded to and supported by a thin peripherally surrounding flexible perforate sheet, of polypropylene or like, which in turn is bonded at its edges to a rectangular rigid metal frame. Such known arrangement is expensive and time-consuming to produce--particularly in view of the curing time necessary for the bonding of the adhesive. Additionally, the mesh and mask are not removably replaceable on the rectangular support frame without destruction of the mesh.
More recently it has been proposed to provide a rigid rectangular support frame wherein on two opposite sides and extending along a substantial part of the length thereof there are mechanical coupling means for interconnection with opposite sides of a metal printing stencil or mask with one mechanical coupling means being mounted on displaceable support means which are displaceable to tension the sheet when connected between the coupling means by suitable hydraulic, pneumatic or spring or mechanical tension devices as will be apparent to persons skilled in the art and well known. The mechanical coupling means includes two metal strips which underlie the normally lowermost surface of the mask sheet when in the operative position of the printing frame and mask and are coupled to the mask sheet along two opposite edges by means of a plurality of apertures in each strip at relatively large spacing and secured by screws, rivets or the like. While such arrangement is suitable for relatively small circuit boards, it does have the disadvantage of not permitting circuit boards of large area to be printed because of the projection of the opposite side strips of the mechanical coupling means beneath the lowermost surface of the mask. Additionally, the arrangement produces a very rigid mask when tensioned which may not allow for slight irregularities in the circuit boards which were tolerated by the first abovementioned arrangement.

Support frame and stencil having flexible end regions for attachment to the support frame


A local positioning device detects a local position of an automobile advancing along a lane formed on a road in a direction. A digital image data indicative of an advancing direction view observed from the automobile in the advancing direction is applied to the local position device. An edge extractor, a threshold generator, and a contour extractor are operable for extracting a contour data indicative of the lane from the image signal. A coordinate convertor converts the contour data into a plane view data indicating the dimensions of extracted contours correctly. A matching operator matches a line or an arc with each of extracted contour. A lane mark contour extractor selectively extracts a pair of extracted contours corresponding to the lane on which the automobile is located.

1. Field of the Invention
The present invention relates to a local positioning apparatus for use in a local positioning system for providing local positioning data related to location, velocity, and posture of an object on the local ground and particularly suitable for detection of both the moving and stationary states of an automobile on the road.
2. Description of the Prior Art
In FIG. 30, a conventional local positioning apparatus used in an automobile is shown. The conventional local positioning system LPP includes an edge extractor 1P, a threshold generator 3P, a contour extractor 5P, a matching operator 9P, and a lane mark contour extractor 11P, a region limiter 13P, a current position detector 15P, a curvature detector 17P, and a yaw angle detector 19P.
The edge extractor 1 is connected to a digital imaging device 100 mounted on an automobile AM (FIG. 1) for obtaining a perspective view Vi of the object located in an advancing direction of the automobile AM. The edge extractor 1 receives the image signal Si indicating the advancing direction view Vi (FIG. 3) of the road surface wherein lane markings Lm1, Lm2, and Lm3 are applied. The edge extractor 1 extracts edge pixels from the signal Si and produces an extracted edge pixel signal Sx' indicative of an extracted edge view Vx' including edge pixels of the lane makings Lm.
The threshold generator 3P determines a threshold Eth' to extract the edge pixels around the contour of the image of the lane makings from the edge pixel data signal Sx' according to a known method. The contour extractor 5 scans the signal Sx' with respect to the threshold Eth' to extract a line of each lane marking Lm, and produces an extracted lane marking signal Sc'.
The matching operator 9P determines the straight or curved line matching the extracted lane contour line data Sc, and produces a matching signal Sm' including dimensional data of such matching lines. The lane mark contour extractor 11P extracts only the matching lines satisfying the possible dimensional features of lane marks on the road from the signal Sm' to produce an extracted lane signal Smc'.
Based on the extracted lane signal Smc', the region limiter 13P determines a region around each of the thus extracted lane marking lines having a predetermined area. Then, the region limiter 13P produces a region signal Sr' defining the regions.
Based on the region signal Sr', the edge extractor 1 limits the area to scan around the detected lane markings. The current position detector 15P detects the position with respect to the road on which the automobile AM is currently located. The curvature detector 17P obtains the curvature of the lane. The yaw angle detector 19P detects the tilting angle of the automobile with respect to the lane.
However, according to the perspective view, since the three-dimensional relationships are represented on a two-dimensional surface, the distant object is represented by a smaller size than the near object. The object's shape is distorted more depending on the distance remote from the imaging device 100 or the automobile AM.
Since the three-dimensional relationships are represented on a two-dimensional surface in the perspective view, the distant object is represented by a smaller size than the near object. In other words, an object in a position far from the automobile AM is expressed in a distorted shape more than that in a position nearby. Note that the images obtained by the signals Si, Sx', and Sc' operate to express the actual (true) shape of the object as a plan view for example.
It is impossible to obtain correct dimensional information of the object from the signal Sc' regardless the distance between the object and the imaging device 100. This clearly means that correct dimensional information of the road (lane) cannot be obtained, and much less the positional relationships between the automobile and the road.
Note that all positioning operation such as matching, lane contour extraction, current position detection, curvature detection, and yaw angle detection are performed based on such incorrect dimensional information included in the signal Sc. Apparently, positioning operation by the conventional local positioning apparatus LPP is incorrect, unreliable, and hazardous.
Another conventional local positioning apparatus is proposed in Japanese Laid-Open Patent Publication H3-139706. According to this conventional local positioning apparatus, an image of two lane marks for guiding an automobile is taken by an imaging device. Two tangent lines having different lengths are drawn to those two lane marks for calculating a curvature of the lane marks. Based on this calculated curvature and a relationship between a curvature and automobile conditions which are previously stored therein, the shifting distance in a lateral direction is obtained.
However, sometimes the lane has a curvature too small to detect correctly. Furthermore, when an interval between two lane markings varies, the conventional local positioning apparatus cannot function properly. As a result, a local position of the automobile on a road cannot be detected.

Matsushita Electric Industrial Co., Ltd.


A data processing unit calculates image conversions parameters corresponding to each partial image, geometrically converts photographed partial images on the basis of a current partial image based on the calculated image conversion parameters, and combines them to generate a mosaic image. Also, a display device displays each current partial image, and at least part of the generated mosaic image.

Conventionally, image combining approaches have been known for dividing a subject into a plurality of partial images which are photographed, and combining the partial images with one another with estimation of a positional relationship among the respective partial images to generate an image called a mosaic image which has a wider viewing angle and a higher definition.
For example, Non-Patent Document 1 (Naoki Chiba, Hiroshi Kayano, Mitihiko Mino, Shouji Yasuda, "Image Mosaicking Based on Image Features," Transaction of The Institute of Electronics, Information and Communication Engineers D-II, Vol. J82-D-II, No. 10, pp.1581-1589) discloses a method of generating a mosaic image by estimating a positional relationship among respective partial images based on motion vectors within the partial images generated by an image analysis. Specifically, sites (corresponding points) which are similar in distribution of luminance value are found from two partial images which were photographed at nearest times, and image conversion parameters are calculated for making a geometrical conversion (movement, rotation, scaling up/down) such that all of them overlap each other. Then, one partial image is used as a basis to geometrically convert the other partial image using the calculated image conversion parameters to generate a mosaic image.
The following model, which supposes that a subject is a flat surface, is often used for the image conversion parameters because of its simplicity.
                              (                                                                      u                  2                                                                                v                  2                                                                                1                                              )                =                              (                                                            a                                                  b                                                  c                                                                              d                                                  e                                                  f                                                                              g                                                  h                                                  1                                                      )                                          (                                                                                u                    1                                                                                v                    1                                                                                1                                                      )                                              [                  Equation                                                              1                ]            where (u1, v1, 1), (u2, v2, 1) are homogeneous coordinates of respective corresponding points, a, b, c, d, e, f, g, h are image conversion parameters, and t is an arbitrary constant.
Also, for further simplifying the model, a restraint condition may be applied to the image conversion parameters, such as g=h=0, a=e=cos θ,−b=d=sin θ, and the like.
In the approach described in the aforementioned Non-Patent Document 1, a camera must be moved such that an overlapping portion exists between two partial images. Otherwise, no corresponding points would exist between the partial images, resulting in a failure in calculating the image conversion parameters. Also, if part of the subject is not photographed when the partial images are photographed, a mosaic image lacks the partial images, so that a user must exhaustively photograph the subject.
Patent Document 1 (Japanese Patent No. 2744265 (pages 5-7, and FIG. 3) describes an example of an image combining system for displaying a screen to guide a user having a camera to take a photograph such that the foregoing condition will be satisfied. The configuration of this conventional image combining system described in Patent Document 1 is illustrated in FIG. 1.
In FIG. 1, 101 designates a camera body; 102 a shutter button; 103 a display device, 104 and 105 a switch for instructing whether the camera is panned in the left-hand direction or right-hand direction; and 106 a lens for focusing a subject on a film or an imager device.
FIG. 2 illustrates an exemplary display by display device 103 of the image combining system illustrated in FIG. 1.
For example, when the camera is panned in the right-hand direction, as the right-hand direction is entered through switch 105, right side area 202 of partial image 201, which has been already photographed, is displayed in a left end area of displayed image 203. Further, left side area 205 of partial image 204 currently captured by the camera is combined in the remaining right side screen of displayed image 203 as a moving image, and the resulting image is displayed.
The user moves (pans) camera body 101 in parallel with an imaging plane, with reference to displayed image 203 on display device 103, such that right side area 202 of previously photographed partial image 201 is not discontinuous to left side area 205 of partial image 204 currently captured by the camera at the boundary therebetween, and depresses shutter button 102 to photograph the partial image. In this way, the mosaic image is generated by moving the camera toward a site of the subject not yet photographed, while including an overlapping area between the previously photographed partial image and the partial image currently captured by the camera, and sequentially photographing partial images.
However, in the conventional image combining system described in the above-mentioned Patent Document 1, the camera body must be moved in the vertical direction and horizontal direction, for example, if an image combining system is manufactured for photographing a subject which is broad in both the vertical and horizontal directions, based on the technique of Patent Document 1. Since a direction in which the camera is moved must be previously specified by the switch, a problem arises in that the operation is very complicated. Accordingly, the image combining system described in Patent Document 1 is of a configuration which is not suitable for photographing a subject which is broad in the vertical and horizontal directions.
Also, in the image combining system described in Patent Document 1, the camera body must be moved in parallel with the imaging plane, and the amount of movement must be adjusted such that a previously photographed partial image is not discontinuous to a partial image currently captured by the camera at the boundary therebetween. Thus, the user is required to perform subtle operations, causing a problem that the user experience considerable difficulty taking photographs.

Image combining system, image combining method, and program


A non-volatile storage apparatus (e.g., an SSD, embedded memory, memory card, etc.) comprises non-volatile memory (e.g., one or more memory dies) connected to a control circuit (e.g., controller, state machine, microcontroller, etc.). The non-volatile memory is configured to have multiple regions for storing different types of data using separate streams. The control circuit is configured to receive a request to write data to a logical address, automatically choose a stream (and corresponding destination region) by determining which of the multiple regions/streams has a sequence of logical addresses associated with previous writes that best fits the logical address for the received data, and store the received data in the chosen destination region of the non-volatile memory using the chosen stream.

Many electronic devices make use of an embedded or otherwise connected memory. Often, the embedded or connected memory includes non-volatile memory. An electronic device that includes an embedded memory or is connected to an external memory is referred to as a host. Examples of host systems include smartphones, laptops, desktop computers, servers, smart appliances, digital cameras, video cameras, etc.
A non-volatile memory allows information to be stored and retained even when the non-volatile memory is not connected to a source of power (e.g., a battery). Examples of non-volatile memory include flash memory (e.g., NAND-type and NOR-type flash memory), Electrically Erasable Programmable Read-Only Memory (EEPROM), and others. One example of a memory device that uses semiconductor based non-volatile memory is a solid state drive.
Non-volatile memory has become more popular and is now being used with more applications. For example, non-volatile memory is being used to store media, such as images, audio and/or video. When used to store media from a sensor (e.g., still camera, video camera, audio recorder), write performance is important to the user. For example, it is not desirable to require a camera to pause recording due to a slow memory.

Multi-stream non-volatile storage system


A fluid catch container for sampling and drain valves provides for the containment of any residue which may leak or drip from the outlet of such a valve. The container is selectively openable and closable, providing easy access for the taking of a sample or for the draining of fluid from the outlet. A rotatable closure serves to prevent the flooding of the catch container due to rain or other agent(s) and the undesirable distribution of any residue due to wind action. The base of the container is removable for emptying and cleaning, and alternatively may be replaced with a fitting for a larger residue collection container. The device is preferably formed of corrosion resistant materials, such as stainless steel, although other materials (e.g., plastics, etc.) may be used. The device is particularly useful in the petroleum, petrochemical, and chemical industries, or any environment where fluid samples must be taken on a regular basis from regular points in a processing system.

It is generally considered standard procedure, if not a requirement, in many industries to take samples of various fluids periodically. In fact, in many industries these samples are taken at regular times and at regular points in the industrial process. The process may be adjusted according to the results obtained from analysis of the sample(s) and depending upon the specific industrial process. The above procedure is generally used in the petroleum, petrochemical, and chemical fields, and is also used in the food processing and other industries. Moreover, from time to time it is necessary to drain a valve, line or tank associated with some part of the system or process in a given industry.
It will be evident that some fluid residue will remain within the pipe or tube downstream from the valve, due to the viscosity and surface tension of the fluid, after a sample is taken or a valve, line or tank is drained. This residue eventually drips from the lower end of the drain or sampling outlet to contaminate the area immediately therebeneath. In many instances, the fluid or chemical residues may be corrosive, poisonous, or otherwise harmful or hazardous. Even in the food industry, such residue may be attractive to vermin or subject to spoilage or otherwise contribute to an unsanitary condition.
Accordingly, the Environmental Protection Agency has formulated regulations requiring that such residues be contained rather than merely allowed to flow outward into the immediate environment. The solution often used is merely to place a bucket, can or other open container immediately below the outlet to catch any residue which may drip therefrom. However, this can be an unsatisfactory solution, particularly for the outdoor environment where the outlet and container are exposed to the weather. In such situations, wind can often blow the dripping residue away from the container below and contaminate the immediate area. Further, rain can easily fill such an open container and cause any residue therein to overflow the container if the residue is less dense than water; a relatively small amount of precipitation may be sufficient to cause such a problem, if the container is positioned so as to catch some amount of runoff from a tank, pipe or valve above.
Another solution is to install a cap on the end of the drain or sample tube or pipe outlet. However, when the cap is removed the residue may overflow the relatively small volume of the cap and contaminate the hand and/or equipment of the worker, thus requiring additional cleanup time and effort, as well as possibly exposing the worker to potential health hazards. As can be seen, none of the solutions developed for the above problem have proven completely satisfactory.
Accordingly, the need arises for a fluid catch collector or container installable on a sampling or drain tube or pipe outlet, which container may be opened temporarily in order to obtain a sample of fluid from the tube or pipe. The container must be closable, in order to preclude the spillage of fluid therein due to wind or other causes and further to prevent the entry of other matter (e.g., rain) into the container. The fluid catch container must also provide means for the draining or removal of fluid residue captured therein, and provide for easy cleanup of the residue container. The device moreover must be adaptable to larger containers as needed.

Fluid catch collector for sampling and drain valves


A semiconductor structure and method of fabricating the structure. The method includes removing the backside silicon from two silicon-on-insulator wafers having devices fabricated therein and bonding them back to back utilizing the buried oxide layers. Contacts are then formed in the upper wafer to devices in the lower wafer and wiring levels are formed on the upper wafer. The lower wafer may include wiring levels. The lower wafer may include landing pads for the contacts. Contacts to the silicon layer of the lower wafer may be silicided.

To maximize the performance of integrated circuits the fabrication process is adjusted to enhance the performance of different devices and circuits in different regions of the integrated circuit chip. This can be difficult and costly to accomplish when; for example, thermal cycles that are required by one set of devices can adversely affect other devices on the same integrated circuit chip. Further, it is often difficult to center the fabrication process tightly around the device specifications for different types of device simultaneously. Therefore, there is a need for integrated circuit chips and methods of fabricating integrated circuit chips wherein the fabrication process may be adjusted to enhance the performance of different types of devices in a cost effective manner.

International Business Machines Corporation


The present invention relates to a de-icing arrangement for de-icing a structural element {170; 270; 370). The structural element could be made of a whole polymeric or metallic material. The arrangement comprises a power source (250) being electrically connected to an electrode configuration (200), said power source is arranged to, when applicable, electrically charge said electrode configuration (200). The electrode configuration (200) is arranged to generate an impulsive force (Fn) for removal of ice adhered on said structural element (170; 270; 370). The invention relates to a method for de-icing a structural element. The invention also relates to a computer program and a computer program product. The invention also relates to a platform carrying the arrangement.

Related Field
The present invention relates to an arrangement and method for de-icing a structure. In particular the invention relates to an arrangement and method for de-icing a whole polymeric (fiber reinforced) or metallic wing or propeller. The invention also relates to a computer programme and a computer programme product. The invention also relates to a platform carrying the arrangement.
Description of Related Art
Aircrafts are continuously exposed to varying climatic condition and among the extremes situation is ice accretion one of the most threatening events. Ice accretion is known to cause serious perturbation to the flying conditions due to ice formations in aerodynamic surfaces of aircraft.
Ice accretion on aircrafts is a very complex physical process. The selection of an adequate ice rejection technique is thus a difficult task. The technique to be selected must be made compatible with a number of constrains comprising materials properties, fatigue, dynamic deformation while in flight, birds collision withstanding ability, repairing and servicing constrains, durability, etc. just to name a few. Therefore, any method to be considered has to be carefully analyzed in its total context to end up with technical conclusions of value.
One of the issues now upcoming is to be found on the growing need of fuel consumption reductions which in turn impose requirements of weight reduction and exceptional aerodynamic constrains, especially laminar air flow. This has been leading to the development of the Smart Fix-wings Aircraft concept where the wings are thought to be made of light weight fiber reinforced epoxy. The removal of ice can be accomplished either by providing melting heat or mechanical stresses to the skin just to surpass adhesion forces of the accreted ice layer. Heat however is known to demand too much power, and in the case of epoxy based material, high temperature is an ageing factor that should be avoided. Mechanical stresses on the other hand should be impulsive to minimize the energy consumption and to accomplish ice cracking while destroying the ice surface adhesion. The accreted ice will then be removed mainly due to the drag forces of the air. Therefore, actuators able to accomplish wing skin surface displacements through the action of impulsive forces are highly interesting.
U.S. Pat. No. 5,584,450 depicts an electro-expulsive de-icing system for attachment to an airfoil which is comprised of a plurality of electro-expulsive elements separated by a dielectric filler regions all of which are disposed between a top dielectric layer and a bottom dielectric layer. A contiguous top skin layer covers the entire de-icing apparatus.
U.S. Pat. No. 5,129,598 depicts an attachable electro-impulse de-icer for de-icing an aircraft structural member including an inductor coil disposed in proximity with the outer surface of the structural member. The coil is supported by a flexible ice-accumulating support member that permits the coil to move relative to the structural member. The coil and the support member may be formed in an integral construction that can be attached to the leading edge of the structural member. The coil and the support member are rapidly displaced away from the structural member upon passing a short-duration, high current pulse through the coil.
Known ice rejection methods are mostly conceived for metallic skin materials and are mostly inductive or thermal (heating). There are even methods that accomplish deicing through total deformation (inflatable layers, etc.).
Known drawbacks of some of the methods are related to the fact that those ice rejection devices introduce significant local perturbation to air flow. Since laminar flow, particularly at wing surfaces, is a much wanted feature from the view point of aerodynamic considerations, any protrusion to the surfaces is not acceptable.
Another drawback of known deicing methods is to be found in the melting of the interlayer of ice and wings which may lead to a gliding effect of the accreted ice pushing it back of simply generating water that flows back and risk to be frozen at the ailerons of aircraft wings.

Method and arrangement for de-icing a structural element


Described herein are techniques for self-synchronization of wireless nodes. For example, the technique may involve determining a repetition rate for receiving a signal from another access point, wherein the repetition rate identifies the another access point. The technique may also involve receiving at the access point an unmodulated impulse radio (IR) ultra wide band (UWB) pulse train from the another access point during a transmission interval associated with the repetition rate. The technique may also involve synchronizing a first clock associated with the access point to a clock associated with the another access point based on the received unmodulated IR UWB pulse train.

Aspects of the present disclosure relate generally to communication systems and to techniques for self-synchronization of wireless nodes.
Wireless communication networks are widely deployed to provide various communication content such as voice, video, packet data, messaging, broadcast, etc. These wireless networks may be multiple-access networks capable of supporting multiple users by sharing the available network resources. Examples of such multiple-access networks include Code Division Multiple Access (CDMA) networks, Time Division Multiple Access (TDMA) networks, Frequency Division Multiple Access (FDMA) networks, Orthogonal FDMA (OFDMA) networks, and Single-Carrier FDMA (SC-FDMA) networks.
A wireless communication network may include a number of base stations that can support communication for a number of mobile entities, such as, for example, user equipments (UEs). A UE may communicate with a base station via the downlink (DL) and uplink (UL). The DL (or forward link) refers to the communication link from the base station to the UE, and the UL (or reverse link) refers to the communication link from the UE to the base station.
Timing synchronization may be an important aspect of wireless network nodes. For example, timing synchronization may provide information to determine a local position of each network node and/or user equipments. In an example, indoor positioning may be desirable. In some systems, satellite-based approaches such as Global Position System (GPS), Global Navigation Satellite System (GLONASS), Galileo, etc. signals may be used for timing synchronization and/or positioning. In some cases, the satellite-based approaches may not be available or may not be desirable. In this context, there remains a need for methods and systems for timing synchronization and/or positioning of network nodes using signaling between the network nodes.

Network self-synchronization using ultra wide band (UWB) impulse radio (IR) pulse train with unique repetition rates


The present invention relates generally to a medical device and method of use, and more specifically to a method and apparatus with coaxial components used to treat venous diseases. The apparatus according to various embodiments operates as an inferior vena cava filter, a clot puller, a clot shredder, and as a prosthetic venous valve.

Deep Venous Thrombosis patients experience clotting of blood in the large veins of the lower portions of the body. These patients are constantly at risk of a clot breaking free and traveling via the inferior vena cava to the heart and lungs. This process is known as pulmonary embolization. Pulmonary embolization can frequently be fatal, for example when a large blood clot interferes with the life-sustaining pumping action of the heart. If a blood clot passes through the heart, it will be pumped into the lungs and may cause a blockage in the pulmonary arteries. A blockage of this type in the lungs will interfere with the oxygenation of the blood causing shock or death.
In the case of venous disease, there are estimated to be over 2 million cases of deep venous thrombosis (DVT) in the U.S. each year. Only about 700,000 are diagnosed, and approximately 200,000 people die of pulmonary embolism, a complication of DVT, causing it to be the third leading cause of death in the U.S., more than breast cancer and AIDS combined. Sixty to seventy percent of patients with DVT eventually experience post thrombotic syndrome (PTS) as a result primarily of damage to the venous valves secondary from the cellular response and overgrowth because of the thrombus. Recurrent DVT will affect a large percentage of those who suffer from the initial episode, further compounding the problem. Therefore, millions of patients will suffer from the acute and chronic problems and health risks posed by DVT.
Thrombosis and atherosclerosis are common ailments which occur in humans and which result from the deposition of thrombus and clot on the walls of blood vessels. When hardened, such deposits are commonly referred to as plaque. Such deposits are most common in the peripheral blood vessels that feed the limbs of the human body and the coronary arteries which feed the heart. Stasis, incompetent valves, and trauma in the venous circulation cause thrombosis, particularly occurring as a deep vein thrombosis in the peripheral vasculature. When such deposits build-up in localized regions of the blood vessel, they can restrict blood flow and cause a serious health risk.
In addition to forming in the natural vasculature, thrombosis is a serious problem in "artificial" blood vessels, particularly in peripheral femoral-popliteal and coronary bypass grafts and dialysis access grafts and fistulas. The creation of such artificial blood vessels requires anastomotic attachment at at least one, and usually at at least two, locations in the vasculature. Such sites of an anastomotic attachment are particularly susceptible to thrombus formation due to narrowing caused by intimal hyperplasia, and thrombus formation at these sites is a frequent cause of failure of the implanted graft or fistula. The arterio-venous grafts and fistulas which are used for dialysis access are significantly compromised by thrombosis at the sites of anastomotic attachment and elsewhere. Thrombosis often occurs to such an extent that the graft needs to be replaced within a few years or, in the worst cases, a few months.
The human venous system in the lower extremities contains a number of one-way valves that function in allowing forward (antegrade) blood flow to the right atrium of the heart while preventing reverse (retrograde) flow to the feet. Using the muscle action of the calf to pump the blood, or the "peripheral heart," the body is able to overcome gravitational forces to maintain blood flow back to the heart. The valves thus prevent blood from pooling in the lower extremities. Physiologically functioning valves are capable of withstanding very high proximal pressure gradients with minimal leakage, and can open at very low distal pressure gradients. However, for many patients, venous function is severely compromised by chronic venous disease (CVD), caused by Chronic Venous Insufficiency (CVI). Many times, CVI is a result of PTS caused by DVT events described above. Over seven million Americans suffer from CVI, a painful and debilitating disease that affects the superficial and deep veins of the legs. Problems associated with CVI include varicose veins, bleeding, ulcerations, severe swelling, deep vein thrombosis, and pulmonary embolism, which may lead to death.
In the venous system, there is also proliferative overgrowth of cellular material at anastomotic sites of the veins with arteries or grafts in the case of dialysis grafts and other surgeries. Most importantly, there is cellular ingrowth of smooth muscle cells into venous valves and the walls of veins after DVT, especially if the thrombus is not cleared quickly. This proliferative cellular response has some similarities to the cellular response that occurs in arteries. The venous valves are particularly affected by deep venous thrombosis and by the eventual cellular response which evolves into a tough and thickened tissue, and the valves become stiff and non-compliant causing them to become incompetent and allowing venous reflux to develop. The ongoing reflux results in venous hypertension, dilated veins, and a plethora of symptoms, including swelling of the lower leg, heaviness, pain, skin discoloration, and even skin ulcers. Collectively, the symptom complex occurring after episodes of DVT and caused mainly by the incompetent venous valves has been referred to as the Post Thrombotic Syndrome (PTS.) Strategies have been employed to remove the venous thrombosis early, by mechanical catheters and pharmacomechanical (mechanical catheters and lytic agents) treatments, and are generally successful and the incidence of PTS is much less than if treated by non invasive means. However, venous reflux still occurs in some of these patients, probably the result of residual thrombus on the valves after the majority of thrombus has been removed and the resulting cellular proliferation that ensues. The cellular ingrowth is a complicated series of events resulting in smooth muscle infiltration, collagen deposition, and fibroblast proliferation, amongst other features that renders the valve leaflet enlarged, stiff, and frequently fused to the vessel wall incapable of function or even being repaired.
The current methods of treating venous diseases including DVT and its complications, notably pulmonary embolism and PTS, are much less than satisfactory for several reasons. The most common method of treating DVT is to administer Heparin, an anticoagulant which does not dissolve the clot, but prevents additional clot from forming. Ninety-five percent of patients treated for DVT are currently treated with Heparin. Heparin administration is convenient and fairly easily done, although it can be expensive. This method relies on the body's inherent thrombolytic processes to dissolve the clot. The main problem with Heparin administration, however, is that all of the clot does not dissolve or it does not dissolve very quickly, and there is resultant residual clot and damage to the venous valves which will lead to PTS. Several studies have documented that there is a lesser incidence of PTS when the thrombus is removed early on in the course of DVT, before the valves are damaged, and that the incidence of recurrent DVT is lessened when the thrombus is removed early on.
In an effort to remove the thrombus early and prevent recurrent DVT and PTS, devices and methods have been invented to remove the thrombus. Initially, in the early 1980's systemic thrombolysis was attempted with a thrombolytic drug. While this method was partially successful, the incidence of bleeding intracranially and in the gastrointestinal (GI) tract was unacceptable. Later, in approximately 1990, a method of catheter directed thrombolysis was developed in which the thrombolytic drug was infused directly into the thrombus. This worked, but the bleeding complications prevented widespread adoption. Around 2000 or so, a procedure termed pharmacomechanical thrombolysis was utilized in which the catheter mechanically agitated the thrombus while the lytic agent was being infused. Again, the bleeding complications were a deterrent to use and even the mechanical action along with the lytic drug did not remove all of the thrombus in most cases. Subsequently, "isolated" pharmacomechanical thrombectomy was developed in which the lytic drug is contained within a section of the vein that is being treated, and most of the lytic drug does not enter the systemic circulation. This was an improvement, and the bleeding complications are lessened. These devices, however, are expensive and carry some risk to the patient, including bleeding, and are frequently not successful in removing all of the thrombus. In fact, the clot is removed completely in the minority of patients and only partially in others. This sometimes necessitates continuing the lytic therapy overnight or for several days in the intensive care unit which is expensive and adds the extra risk of systemic exposure to the lytic agent with subsequent bleeding. The continued lytic therapy raises the potential for bleeding in the GI tract, brain, and elsewhere. Hence, the added cost of the drug and the ICU monitoring and the added risk of protracted exposure to higher levels of the lytic drug is not only problematic to those patients treated in this manner, but they are also a deterrent to other patients even having the procedure which may help them avoid the long term sequelae of aggressive interventional therapy for DVT.
The main reason for subjecting the patient to the additional expense and risk of protracted lytic infusion is that the thrombolytic and thrombectomy devices designed to treat the thrombus within the veins do not remove all of the thrombus. It is well known and accepted in the medical field that these prior art devices only remove or dissolve acute thrombus. The subacute or chronic thrombus which is frequently present is resistant to thrombolysis and thrombectomy. The development of DVT is usually a slow progressive process, and the patient does not really know, and it cannot be determined with any degree of certainty, when the DVT began and, hence, how old the thrombus is, whether acute, subacute, or chronic. Therefore the treating physicians really don't know or have the means to determine if the thrombolytic and thrombectomy devices available to them will work or not. This unknown is a deterrent for using an invasive, potentially dangerous, and very expensive method that may help the patient, but may not. This unknown prevents many patients from receiving aggressive therapy that may be beneficial to them. Both the lack of success of the prior art devices and the fact that many patients are not treated because of this unknown leaves the patient with residual thrombus which demands further costly treatment methods and increases the risk of valvular damage which predisposes the patient to develop recurrent DVT, chronic venous insufficiency and PTS later. There is a need to provide devices and methods that will rid the patient of all of the thrombus, including the subacute and chronic thrombus that prevents adequate treatment in many cases.
Traditionally, pulmonary embolization may be prevented by the appropriate placement of a thrombus filter in the vascular system of a patient's body. Placement of the filter may be accomplished by performing a laparotomy with the patient under general anesthesia. However, intravenous insertion is often the preferred method of placing a thrombus filter in a patient's vascular system.
Intravenous insertion of a thrombus filter is less invasive and it requires only a local anesthetic. In this procedure, the thrombus filter is collapsed within a delivery catheter. The delivery catheter is introduced into the patient's vascular system at a point which is convenient to the physician. The delivery catheter is then fed further into the vascular system until it reaches a desirable location for filter placement. The thrombus filter is then released into the blood vessel from the delivery catheter.
In the treatment of Deep Venous Thrombosis, a thrombus filter is placed in the inferior vena cava of a patient. The inferior vena cava is a large vessel which returns blood to the heart from the lower part of the body. The inferior vena cava may be accessed through the patient's femoral vein.
Thrombus filters may be placed in other locations when treating other conditions. For example, if blood clots are expected to approach the heart and lungs from the upper portion of the body, a thrombus filter may be positioned in the superior vena cava. The superior vena cava is a large vessel which returns blood to the heart from the upper part of the body. The superior vena cava may be accessed through the jugular vein, located in the patient's neck.
Once placed inside a blood vessel, a thrombus filter acts to catch and hold blood clots. The flow of blood around the captured clots allows the body's lysing process to dissolve the clots.
The walls of the blood vessels are lined with a thin inner membrane or intima. When the securing/anchoring portions of a thrombus filter puncture this inner membrane, the body responds to a puncture of the intima with a process known in the art as neointimal hyperplasia. As a result, the punctured area of inner membrane is overgrown with a number of new cells. The securing portions of the thrombus filter are typically encapsulated with new cell growth (neointimal hyperplasia). Because the portions of the filter contacting the blood vessel wall become fixed in this way, it is impractical to remove many prior art filters percutaneously after they have been in place for more than two weeks.
There are a number of situations in which it may be desirable for a physician to remove a thrombus filter. If the physician determines that more effective filtering would occur with a thrombus filter in a different position, the physician may remove the original filter from its present positions and deploy a new filter in a new position. If the physician determines that the risk of blood clots forming is no longer present, it may be desirable to remove the thrombus filter completely. Thrombus filters are often used in conjunction with anticoagulation drugs. At some point, the physician may desire to discontinue the use of anticoagulation drugs. The physician may also want to remove the thrombus filter in conjunction with discontinuing the anticoagulation drugs. The removal of the thrombus filter from the patient eliminates any possibility that a complete occlusion will occur at the thrombus filter site. The removal of the thrombus filter also eliminates any possibility that the thrombus filter will become loose and migrate within the blood vessel. A loose thrombus filter is undesirable because it may migrate to a dangerous or life threatening position.
For a general background on thrombus filter technology and some of the tools and apparatus used involving thrombus filters, see U.S. Pat. No. 6,217,600 issued to DiMatteo on Apr. 17, 2001 ("DiMatteo"), the entire disclosure of which is incorporated herein by reference in its entirety.
Conventional implantable thrombus filters (also known as blood filters and/or IVC filters) employing a variety of geometries are known. Many are generally basket or cone shaped in order to provide adequate clot-trapping area while permitting sufficient blood flow. Also known are filters formed of various loops of wire, including some designed to partially deform the vessel wall in which they are implanted. Vena cava filters commonly include a core portion from which a plurality of wires radiate outwardly. The wires serve to filter clots from blood flowing through the vein. Various hook-like projections, barbs and the like have been suggested for use in holding the filter in place once the delivery catheter has been withdrawn.
Some traditional vena cava filters include the Vena Tech-LGM vena cava filter, the Bird's Nest vena cava filter, and the Simon-Nitinol vena cava filter. The Vena Tech-LGM filter is a conical filter made from a Phynox alloy, with longitudinal stabilizing legs in addition to the intraluminal cone. The Bird's Nest filter is a "nest" of stainless steel wire which is wound into the vena cava, while the Simon Nitinol filter is a two-stage filter made from nickel-titanium (NiTi) alloy with a conical lower section and a petal-shaped upper section. The TrapEase is a filter laser cut from a single tube of nitinol material and is formed with a symmetric double-basket configuration providing two levels of clot trapping.
Although vascular filters are widely used for capturing emboli in blood vessels, existing filter configurations suffer from a variety of shortcomings that limit their effectiveness. In one shortcoming, vascular filters are susceptible to clogging with embolic material. When a filter becomes partially or totally clogged, the flow of blood through the vessel may be substantially reduced or stopped completely. When this occurs, serious complications can arise and therefore the patient must be treated immediately to restore adequate blood flow. Because of the potential for clogging, existing vascular filters are typically manufactured with relatively large pores or gaps such that only large emboli, such as those with diameters of 7 mm or greater, are captured. The large pore size is necessary for reducing the likelihood of clogging due to smaller particles. Unfortunately, in certain cases, the passage of smaller emboli may still be capable of causing a pulmonary embolism or stroke. Accordingly, physicians and filter manufacturers are required to balance the risk of clogging against the risk of pulmonary embolism and/or stroke.
Traditional indications for filters are patients with deep venous thrombosis, and with a contraindication for anticoagulation, or patients with large floating clots in the iliac veins or IVC, with an imminent risk of embolism. Additional contraindications are young patients or patients with a transient problem that may cause PE not requiring a permanent filter. However, one important problem with many available intravascular filters in use is the non-retrievability of the devices, because while penetration of the retaining hooks of the filter into the lumen of the IVC is necessary for the proper securing of the device, in extreme cases and over time, over-penetration may impinge upon adjacent organs, leading to serious or even fatal complications. Further, with time the filter will be integrated into the aortic wall, making it unretrievable without causing significant damage to the vessel wall, particularly at the body of the basket. Accordingly, a vena cava filter capable of temporary deployment is desired to provide rapid protection against pulmonary embolism. However, as the condition producing blood clots is successfully treated, it may be desired to remove the filter from the vena cava.
Catheter-based mechanical thrombectomy devices provide an alternative treatment method for removing blood clots from a patient's vasculature. Thrombectomy devices are typically used for removing a thrombus that has formed in a blood vessel and has occluded the flow of blood.
See U.S. Pat. No. 7,803,171 issued to Uflacker on Sep. 28, 2010 ("Uflacker") for a general background on thrombus filter technology and some of the tools and apparatus used involving thrombus filters, the entire disclosure of which is incorporated herein by reference in its entirety.
Some attempts have been made to develop thrombus filters that are retrievable and accurately positioned. For example, see U.S. Pat. No. 7,534,251 issued to WasDyke on May 19, 2009 ("WasDyke") which discloses a retrievable vena cava filter of multiple elongated filter legs each having a hook portion configured to releasably secure the filter to the wall of a vessel, and an expandable member releasably connected to the filter. The filter legs may be biased to expand from a substantially straight configuration to an outswept, conical-shaped configuration when deployed in the vessel. The expandable member may include a plurality of securing members configured to pierce and secure the expandable member to the vessel wall. In some embodiments, the expandable member may comprise a bendable member interconnected to several tubular members. In other embodiments, the expandable member may comprise a coiled wire. In use, the expandable member may be utilized to compress the filter legs against the vessel wall. The entire disclosure of WasDyke is incorporated herein by reference in its entirety.
U.S. Pat. No. 4,793,348 issued to Palmaz on Dec. 27, 1988 ("Palmaz") discloses a vena cava filter for preventing migration of lower extremity venous clots into the pulmonary circulation. The Palmaz filter comprises a tubular body, the wall of which is partitioned by a slot pattern into a latticework rendering the tubular body radially expandable; a head piece, having a threaded receiving hole, circumferentially affixed to the distal end of said tubular body; and a plurality of tines affixed in substantially uniform circumferential spacing about the proximal end of said tubular body. In a filter intended for femoral vein introduction into the vena cava, the tines are elongated appendages having hooked terminal ends. In a filter intended for jugular vein introduction, the tines are short spikes. The filter is delivered to the inferior vena cava by catheter means introduced through a vein sheath positioned in the femoral or jugular vein. After location within the caval lumen, the tubular body of the filter is expanded by a balloon catheter contained within the lumen of the filter, thereby rendering the latticework wall surface of the tubular body into a filtering network mesh and affixing the expanded filter within the vena cava. After deployment of the expanded filter within the vena cava, the catheter means is withdrawn. The entire disclosure of Palmaz is incorporated herein by reference in its entirety.
U.S. Pat. No. 4,832,055 issued to Palestrant on May 23, 1989 ("Palestrant") discloses a blood clot filter which includes a central core wire extending along a central longitudinal axis and surrounded by a number of peripheral wires evenly spaced about the central core wire. A first connector connects the peripheral wires together at one end of the central core wire at a first fixed connection point. A second connector connects the peripheral wires together at a second connection point spaced apart from the first connection point, the second connection point surrounding the central core wire and being slidably secured thereto. The blood clot filter includes a one-way lock device permitting the second connector to slide along the central core wire toward the first fixed connector from a first position remote from the first connector to a second position proximate the first connector. However, the lock device prevents the second connector from returning from the second proximate position back to the first remote position. The portions of the peripheral wires extending between the first and second connectors initially extend generally along the central core wire. As the second connector is advanced from the first remote position to the second proximate position, the portions of the peripheral wires extending between the first and second connectors move radially away from the central core wire to a deployed position for forming a filter mesh. The entire disclosure of Palestrant is incorporated herein by reference in its entirety.
U.S. Pat. No. 4,727,873 issued to Mobin-Uddin on Mar. 1, 1988 ("Mobin-Uddin") discloses an embolus trap comprising an expansible article which is inserted in its collapsed condition in a passageway and which then opens and secures itself. The Mobin-Uddin device comprises a central hollow column carrying preferably two or more tiers spaced therealong of radially extending elongated filaments, pairs of which are connected at their outer ends to form loops. Each tier includes two or more such loops and the loops of one tier are positioned circumferentially between the loops of the next adjoining tier. At the outside ends, the filaments are formed into outwardly extending hooks backed by offsets, the latter limiting the penetration of the hooks into the wall of a passageway in which the device is implanted. The filaments are preferably made of metal wire or other filament with sufficient spring to permit them to be folded back against the central column while the device is inserted into a passageway and then, when released, to assume a radially-extended position within the passageway forcing their hooked ends against the passage wall. The device is inserted into a vein by a catheter of plastic tubing having a tubular capsule at its distal end containing the device in its collapsed condition. In the capsule, the filaments are forced against the central column and are relatively straight. When the embolus trap is ejected, its filaments spring outwardly in the vein tending to assume their semi-lunar curvature. A wire guide extends through the hollow central column of the device and out beyond the capsule. The wire guide has a flexible J-tip at its outer end which facilitates maneuvering and prevents securing in the wall of the vein. A hollow push rod which fits over the wire allows the catheter to eject the embolus trap from the capsule so that it travels along the wire guide to its destination. For maneuvering the capsule in place, a different type of hollow rod is provided which will not eject the embolus trap from the capsule. The entire disclosure of Mobin-Uddin is incorporated herein by reference in its entirety.
U.S. Pat. No. 6,258,115 issued to Dubrul ("Dubrul I") describes a stent of varying porosity for use in vessels with bifurcations or side branches. The stent allows for scaffolding of the stenotic area but still allows for flow into the side branches. A distal protection system is also described. Also, Dubrul I discloses a procedure-oriented system for carotid stenting which reduces or eliminates the stroke potential during stent placement by positioning a fragment filteritrap/occluder downstream (distally) from where the stent is disposed within a bifurcated blood vessel such as the common carotid artery. The Dubrul I device includes both a single lumen, multi-porous stent and a bifurcated stent, both of which are operable for stenting the common carotid artery at its point of bifurcation. However, the Dubrul I device is designed for use against blood flow with the most open end on the proximal end and not optimized for use with blood flow with the most open end on the distal end.
U.S. Pat. No. 6,238,412 issued to Dubrul et al. on May 29, 2001 ("Dubrul II"), U.S. Pat. No. 6,695,858 issued to Dubrul et al. on Feb. 24, 2004 ("Dubrul III"), and U.S. Pat. No. 6,221,006 issued to Dubrul et al. on Apr. 24, 2001 ("Dubrul IV"), describe a catheter device for removal of a blockage in a passageway, such as a dialysis graft or in a body passageway. The devices of Dubrul II, III and IV include a traditional funnel-like catheter for reception and aspiration of the blockage and an occlusion engaging element supported on a wire that extends through the catheter. The devices include a braid device that expands against the blood vessel wall to stabilize the catheter and to prevent the occlusion from passing around the outside of the device; blood flow is also prevented from passing through the device.
U.S. Pat. No. 6,699,260 issued to Dubrul et al. on Mar. 2, 2004 ("Dubrul V") describes a catheter device for removal of a blockage in a body passageway fitted with a multi-wing malecot expansion device. Similar to Dubrul II, III and IV, the Dubrul V device entirely blocks blood flow, and the targeted blockage, from passing around or through the device. Further, U.S. Pat. Pub. No. 2010/0114113 to Dubrul et al. published May 6, 2010 ("Dubrul VI") discloses a catheter device for occlusion removal that blocks blood flow.
U.S. Pat. Pub. No. 2004/0260333 to Dubrul et al. published on Dec. 23, 2004 ("Dubrul VII") and U.S. Pat. Pub. No. 2010/0030256 to Dubrul et al. published on Feb. 4, 2010 ("Dubrul VIII") describe a collection of funnel catheters, catheter/dilator assemblies, occluders, and associated methods which either entirely block blood flow or do not allow a controlled, predictable adjustment of allowed blood flow.
The entire disclosures of each of Dubrul I through Dubrul VIII are incorporated herein by reference in their entireties.
The prior art thrombus filter techniques or technologies do not provide a minimal-trauma device that enables predictable and reliable positioning, readily allow repositioning, are easily inserted and retracted, capable of removing all thrombus, including subacute and chronic thrombus. Also, traditional thrombus filters techniques or technologies do not allow pulling or moving of thrombus and/or shredding thrombus.
A variety of methods and devices have been developed for treating thrombosis and atherosclerosis in the coronary and peripheral vasculature, as well as in implanted grafts and fistulas. Such devices and techniques attempt to filter, capture, pull and/or shred thrombus. Techniques include surgical procedures, such as coronary artery bypass grafting, and minimally invasive procedures, such as angioplasty, atherectomy, transmyocardial revasculaturization, and the like. Techniques generally described as "thrombectomy" have been developed. Thrombectomy generally refers to procedures for the removal of relatively soft thrombus and clot from the vasculature. Removal is usually achieved by mechanically disrupting the clot, optionally with the introduction of thrombolytic agents. The disrupted thrombus or clot is then withdrawn through a catheter, typically with a vacuum or mechanical transport device.
Thrombectomy generally differs from angioplasty and atherectomy in the type of occlusive material which is being treated and in the desire to avoid damage to the blood vessel wall. The material removed in most thrombectomy procedures is relatively soft, such as the clot formed in deep vein thrombosis, and is usually not hardened plaque of the type treated by angioplasty in the coronary vasculature. Moreover, it is usually an objective of thrombectomy procedures to have minimum or no deleterious interaction with the blood vessel wall. Ideally, the clot will be disrupted and pulled away from the blood vessel wall with no harmful effect on the wall itself.
While successful thrombectomy procedures have been achieved, most have required comprise between complete removal of the thrombosis and minimum injury to the blood vessel wall. While more aggressive thrombectomy procedures employing rotating blades can be very effective at thrombus removal, they present a significant risk of injury to the blood vessel wall. Alternatively, those which rely primarily on vacuum extraction, together with minimum disruption of the thrombus, often fail to achieve sufficient thrombus removal.
For example, U.S. Pat. No. 6,660,014 issued to Demarais on Dec. 9, 2003 ("Demarais I") provides apparatus, systems, methods, and kits for removing occlusive material from body lumens. Demarais discloses a macerator for breaking up or "disrupting" the thrombus, clot, or other occlusive material, where the macerator is positioned to minimize or prevent contact with and reduce or eliminate the potential for injury to the luminal wall. The device comprises a catheter for removing the occlusive material from the body lumen. The catheter comprises a catheter body having a proximal end, a distal end, and a lumen therethrough. A radially expansible positioning cage is disposed on the catheter body near its distal end, and a macerator is disposed within the expansible positioning cage. The macerator is configured to disrupt occlusive material within the cage when the cage is expanded against the luminal wall. The macerator is typically a rotating element, such as a helical or other shaped wire which engages and disrupts the occlusive material. Usually, the disrupted material will also be drawn into the catheter body lumen. Alternatively, the disrupted thrombus can be captured, in whole or in part, by a second catheter usually introduced downstream from the first catheter with the macerator. The second catheter may also comprise a macerator and, in some instances, the two catheters can be similar or identical. In all cases, the disrupted thrombus may be removed through the catheter lumen by aspiration using an external vacuum source and/or a mechanical pump. U.S. Pat. No. 6,945,977 issued to Demarais on Sep. 20, 2005 ("Demarais II") provides additional embodiments of the devices and methods of use to that of Demarais I. Both Demarais I and Demarais II are incorporated herein by reference in their entireties.
U.S. Pat. No. 7,686,825 issued to Hauser on Mar. 20, 2010 ("Hauser") provides a vascular filter device adapted for capturing and breaking down embolic material from the blood. The Hauser device generally comprises a filter body sized for deployment in a blood vessel and an agitation member movably coupled to the filter body. During use, movement of the agitation member acts to break apart particles captured within the filter body. To reduce the possibility of filter migration, the filter body may be provided with anchoring elements for engagement with an inner wall of the blood vessel. The anchoring elements may comprise penetrating tips, barbs, hooks or any other structure configured to engage the inner wall. In another variation, the filter device may be supported by a stent structure that expands for engagement with the inner wall.
The venous system of the legs uses valves and muscles as part of the body's pumping mechanism to return blood to the heart. Venous valves create one way flow to prevent blood from flowing away from the heart. When valves fail, blood can pool in the lower legs, resulting in swelling and ulcers of the leg. The absence of functioning venous valves can lead to chronic venous insufficiency.
The presence of CVI results from damaged (incompetent) one-way vein valves in leg veins. These valves normally allow forward flow of blood to the heart, and prevent blood from pooling at the feet. However, incompetent valves allow reflux of blood, causing clinical problems. There are few effective clinical therapies for treating CVI other than compression stockings and elevating the leg. Vein valve transplantation is a surgical option for treatment. However, it is often difficult to find suitable donor valves. Very few prosthetic valves developed in the past have demonstrated sufficient clinical or mechanical functionality. Persistent problems include thrombus formation, leaking valves, and valves that do not open at physiologic pressure gradient. There is a rather uniform problem of fibrin deposition on the foreign substance constituting the prosthetic valve. There has yet to be a prosthetic venous valve developed that has demonstrated the necessary functional performance for operating satisfactorily in human physiologic conditions. While various designs have been pursued in the past, many such designs possess shortcomings that prevent them from being a sufficiently functional design.
Techniques for both repairing and replacing the valves exist, but are tedious and require invasive surgical procedures. Direct and indirect valvuoplasty procedures are used to repair damaged valves. Transposition and transplantation are used to replace an incompetent valve. Transposition involves moving a vein with an incompetent valve to a site with a competent valve. Transplantation replaces an incompetent valve with a harvested valve from another venous site.
Prosthetic valves can be transplanted into the venous system, but current devices are not successful enough to see widespread usage. One reason for this is the very high percentage of prosthetic valves reported with leaflet functional failures. These failures have been blamed primarily on improper sizing and tilted deployment of the prosthetic valve. In addition, a great number of leaflets of the prosthetic valves ultimately become fused to the vein wall.
A typical traditional prosthetic venous valve is provided in U.S. Pat. No. 7,569,071 issued to Haverkost et al. on Aug. 4, 2009 ("Haverkost I") which discloses venous valve frames, venous valves that utilize the venous valve frames, and methods for forming and using the venous valve frame and the venous valve. Various embodiments can be used to replace and/or augment an incompetent valve in a body lumen. Embodiments of the venous valve include a venous valve frame and valve leaflets that can be implanted through minimally-invasive techniques into the body lumen. In one example, embodiments of the apparatus, system, and method for valve replacement or augmentation may help to maintain antegrade blood flow, while decreasing retrograde blood flow in a venous system of individuals having venous insufficiency, such as venous insufficiency in the legs. U.S. Pat. No. 7,951,189 issued to Haverkost et al. on May 31, 2011 ("Haverkost II") provides additional embodiments of the devices and methods of use to that of Haverkost I. Haverkost I and Haverkost II are incorporated herein by reference in their entireties.
U.S. Pat. No. 7,670,368 issued to Hill et al. ("Hill I") on Mar. 2, 2010 discloses an apparatus, system, and method for valve replacement or augmentation. The apparatus can include a valve that can be used to replace or augment an incompetent valve in a body lumen. Embodiments of the valve can include a frame and cover that can be implanted through minimally-invasive techniques into the body lumen. In one example, embodiments of the apparatus, system, and method for valve replacement or augmentation may help to maintain antegrade blood flow, while decreasing retrograde blood flow in a venous system of individuals having venous insufficiency, such as venous insufficiency in the legs. U.S. Pat. No. 7,867,274 issued to Hill et al. on Jan. 11, 2011 ("Hill II") provides additional embodiments of the devices and methods of use to that of Hill I. Hill I and Hill II are incorporated herein by reference in their entireties.
U.S. Pat. No. 7,780,722 issued to Thielen et al. ("Thielen") on Aug. 24, 2010 provides a venous valve with a frame and a cover on the frame for unidirectional flow of a liquid through the valve quite similar to that of Hill I and Hill II. Thielen is incorporated herein by reference in its entirety.
Some attempts have been made to develop venous devices useful and adaptable for multiple applications, see U.S. Pat. No. 5,632,754 issued to Farley et al. on May 27, 1997 ("Farley"), the entire disclosure of which is incorporated herein by reference in its entirety.
Typically, the stability of the catheter tip is problematic and critical to the medical procedure. In many cases a "guide" catheter is inserted and the tip is placed within or near the orifice of the vessel intended to be treated. See for example U.S. Pat. No. 5,947,995 issued to Samuels on Sep. 7, 1999 ("Samuels"), the entire disclosure of which is incorporated herein by reference in its entirety.
For a general background on stenting and guiding catheters, see U.S. Pat. No. 7,645,296 issued to Theron et al. on Jan. 12, 2010 ("Theron"), the entire disclosure of which is incorporated herein by reference in its entirety.
Several devices have been used to place a filtering device into the inferior vena cava using a transvenous route, commonly originating from the right jugular vein or from either femoral vein. For example, the method disclosed in U.S. Pat. No. 3,834,394 to Hunter, et al., ("Hunter") uses a detachable balloon which is delivered to the inferior vena cava at the end of a catheter. The balloon and catheter are inserted into one of the veins in the neck using a surgical incision and passed to the lower inferior vena cava where the balloon is inflated. Once detached, the balloon occludes the inferior vena cava entirely, thereby preventing any flow of blood or blood clots to the heart. While insertion of this device avoids major abdominal surgery, it still requires a small surgical procedure to be performed in order to expose a neck vein. The balloon occludes the inferior vena cava completely, resulting in swelling of the lower extremities until collateral circulation develops around the balloon. With time, these collateral channels may become large enough to permit life threatening emboli to pass to the lung. The entire disclosure of Hunter is incorporated herein by reference in its entirety.
Another device for preventing pulmonary embolism but which does not require total occlusion of the inferior vena cava is an implantable cone-shaped filter device consisting of six spokes with sharpened points at the end and connected together at the other end by a central hub. A thin membrane with 4 mm holes covers the device. The umbrella-like device is folded into a cylindrical capsule connected to the end of a catheter. This device is described in U.S. Pat. No. 3,540,431, to Mobin-Uddin ("Mobin-Uddin"). This device also requires a surgical cutdown on a major right neck vein for access to the venous system. The device and delivery capsule are positioned in the inferior vena cava and released by pushing the device out of the capsule. While the device acts as an efficient filter, approximately 60% of patients using the Mobin-Uddin filter develop occlusion of the inferior vena cava, sometimes resulting in severe swelling of the legs. Furthermore, instances of migration of the filter to the heart have been reported; such instances present a high mortality risk. The entire disclosure of Mobin-Uddin is incorporated herein by reference in its entirety.
U.S. Pat. No. 3,952,747, to Kimmel ("Kimmel"), discloses a blood vessel filter and filter insertion instrument which overcome some of the disadvantages of the previous two devices. The Kimmel patent describes a device which may be inserted either from the jugular or femoral approach using a surgical exposure of a major vein. The conical shaped device consists of six strands of wire each connected to a hub at one end and having recurved hooks on the other end. The device is loaded into a cylindrical delivery capsule which is connected to a catheter. The delivery capsule measures 6 mm in diameter and 5 cm in length. Because of its size, a surgical exposure of the vein is necessary for introduction of the delivery capsule into the vascular system. More recently, the delivery capsule has been introduced into the vascular system through a large catheter using angiographic techniques. However, this technique has been shown to significantly injure the vein at the introduction site. Sometimes it may not be possible to pass the capsule from below through tortuous pelvic veins into the inferior vena cava because of the inflexibility of the capsule. The filter engages the wall of the vein at one end and therefore often tilts to one side. It is very difficult to deliver the filter in a manner that maintains the longitudinal axis of the filter centered along the longitudinal axis of the vena cava. A tilted filter has been shown to be less efficient at capturing blood clots. Migration of the filter has not been a problem. The entire disclosure of Kimmel is incorporated herein by reference in its entirety.
Another method of preventing pulmonary emboli from reaching the lungs is a device disclosed in U.S. Pat. No. 4,425,908, to Simon ("Simon"). This device uses the thermal shape memory properties of Nitinol to deploy the filter following delivery. The filter consists of seven wires banded at one end and also in the middle. The wires between these two points form a predetermined filter mesh derived from the thermal memory. The free-ends of the wires form anchoring points which radially engage the inferior vena cava. The device may be inserted through a jugular or femoral vein approach using standard angiographic catheters. The device relies on the thermal shape memory properties of the Nitinol wire to form an effective filter following delivery. The entire disclosure of Simon is incorporated herein by reference in its entirety.
U.S. Pat. No. 4,494,531, to Gianturco ("Gianturco"), also discloses a blood vessel filter which can be inserted through angiographic catheters. The device consists of a number of strands of wire which are interconnected and wadded together to form a curly wire mesh. The filter includes a number of projections which serve as an anchoring means for anchoring the filter at a suitable body location within the inferior vena cava. Problems with the device include migration and demonstration invitro of filtering inefficiency. The random nature of the filtering mesh makes it difficult to assess the overall efficacy. Perforation of the anchoring limbs through the vena cava has also been described. The entire disclosure of Gianturco is incorporated herein by reference in its entirety.
The use of the above devices can be cumbersome, time-consuming and expensive. Furthermore, these devices do not adequately capture emboli in the blood or remove all thrombus, such as subacute and chronic thrombus. Rather, these devices are typically used to remove a thrombus that has formed within a vessel. In certain cases, these devices may actually produce emboli and cause a stroke or PE. Still further, the contact surfaces or fluid pressures of these mechanical thrombectomy devices may produce a variety of undesirable side effects, such as endothelial denudation and hemolysis. These devices are difficult to position and, in the case of venous valves, unreliable and generally ineffective. Therefore, an urgent need exists for minimal trauma devices and methods for capturing and/or completely removing blood clots from a patient's vasculature and for safely and effectively inserting prosthetic venous valves into a patient's vasculature. The present invention addresses these needs.
The use of the instant inventions and methods are, in the case of venous disease, designed to treat DVT by removing acute, subacute, and chronic thrombus, preventing pulmonary emboli, removing pulmonary emboli, preventing the smooth muscle cell migration and population into the valvular structure which causes valvular incompetence, repairing damaged veins and venous valves, and percutaneously placing prosthetic venous valves.

Devices and methods for treating venous diseases


A ship information display device is provided, which may include a first processor, a second processor, a graphic processor, and a display. The first processor may generate a first image based on first ship information received from a first ship sensor and generate a screen to be synthesized including the first image and a blank image. The second processor may generate a second image based on second ship information received from a second ship sensor. The graphic processor may generate a synthesized screen including the first image and the second image by replacing the blank image of the screen to be synthesized by the second image generated by the second processor. The display may display the synthesized screen.

Devices are known which are mounted to a ship and display, as information related to the ship, ship information, such as a nautical chart including route information of the ship, radar image around the ship obtained from a radar device, an echo image obtained from a fish finder, and meter information, such as a ship speed and an engine speed. WO2013/121458A1 discloses an information display device of which a controller generates images of various kinds of ship information based on the information received from various ship instruments, and simultaneously displays the images in a plurality of areas of a screen, respectively.
In recent years, the amount of information which the information display device for the ship handles has been increasing. For example, since a three-dimensional (3D) echo image which is obtained by three-dimensionally drawing ocean bed topography and positions of detected schools of fish is generated based on the echo information directly below the ship obtained from the fish finder, the 3D image has a remarkably larger amount of information used for the generation compared with the conventional two-dimensional (2D) image. In addition, since a higher information processing capability is needed for the image generation using such a large amount of information, there is a problem that the throughput of the controller might be insufficient when the images are displayed simultaneously with other ship information.

Ship information display device and method of displaying ship information


A vacuum cleaner comprises a suction unit (23) which is drivable by means of a first electric motor (25). A suction attachment (7) of the vacuum cleaner comprises a rotatable brush (41) which is drivable by means of a second electric motor (45). The vacuum cleaner comprises a control unit (29) by means of which an electric current through the first motor (25) can be controlled. In accordance with the invention, the control unit (29) controls the current through the first motor (25) as a function of a mode of operation of the brush (41), which mode can be selected by a user of the vacuum cleaner. In this way, the suction power of the suction unit (23) is adapted to the mode of operation of the brush (41), thereby improving a relationship between cleaning performance, ease of use, current consumption and noise production of the vacuum cleaner. In a special embodiment of a vacuum cleaner in accordance with the invention the control unit (29) controls an air pressure and an air flow in the suction attachment (7) in such a manner that the air pressure does not decrease below a first limit value (H.sub.MIN), the air flow does not exceed a second limit value (Q.sub.MAX), and at least one of the limit values (H.sub.MIN, Q.sub.MAX) is substantially reached.

1. Field of the Invention
The invention relates to a vacuum cleaner including a housing, a suction unit accommodated in the housing and drivable by means of a first electric motor, a suction attachment having a rotatable brush which is drivable by means of a second electric motor, and an electrical control unit for controlling an electric current through the first motor.
2. Description of the Related Art
A vacuum cleaner of the type defined in the opening paragraph is known from EP-B-0 458 057. The known vacuum cleaner has a pressure sensor for measuring an air pressure in the suction attachment. When during operation a user of the vacuum cleaner moves the suction attachment over a surface to be cleaned, the air pressure in the suction attachment fluctuates because the air drawn in by the suction unit via the surface and the suction attachment encounters a fluctuating resistance owing to irregularities in the surface. The pressure fluctuations in the suction attachment have an amplitude which depends on the type of surface over which the suction attachment is moved. The pressure fluctuations are comparatively large when the surface is for example a carpet, whereas the pressure fluctuations are comparatively small when the surface is smooth, as for example in the case of wooden floors or tile floors. The control unit of the known vacuum cleaner comprises a microprocessor which detects the type of surface on the basis of the amplitude of the pressure fluctuations measured by means of the pressure sensor in the suction attachment. The microprocessor controls the currents through both the first motor, which drives the suction unit, and the second motor, which drives the brush, depending on the detected type of surface. In this way, the control unit adapts the suction power of the suction unit and the speed of rotation of the brush to the detected type of surface, so that an optimum relationship between cleaning performance, ease of use, current consumption and noise production of the vacuum cleaner is obtained for different types of surface.
A disadvantage of the known vacuum cleaner is that the pressure fluctuations in the suction attachment are influenced by the manner in which the user handles the vacuum cleaner. If the user, for example, holds the suction attachment in a fixed position on a carpet or moves the suction attachment with a comparatively large hold-down pressure over a carpet, the pressure fluctuations in the suction attachment have a comparatively small amplitude, as a result of which it is possible that the control unit detects a smooth type of surface and does not adapt the suction power of the suction unit and the speed of rotation of the brush to the carpet in an optimum manner. If the user moves the suction attachment away from a smooth floor and puts it back several times in succession, the pressure fluctuations in the suction attachment have a comparatively large amplitude, as a result of which the control unit may detect a carpet. Such misinterpretations by the control unit of the known vacuum cleaner can be prevented by providing the microprocessor of the control unit with a number of additional control rules. However, as a result of this, the control unit becomes comparatively complicated and slow.

Vacuum cleaner with power control in dependence on a mode of operation of an electrical brush


A float system for use in cementing a casing in a wellbore. The wellbore is drilled with a drill bit attached to the casing. The drill bit is removed after the wellbore is drilled. The float system is lowered into the casing after the drill bit is removed. The float system includes a packer apparatus with a float apparatus, preferably a float shoe, attached to the end thereof. The packer apparatus is set in the casing to hold the float shoe in position. A bottom cementing plug is placed in the casing and is urged downwardly until it engages the upper end of the packer apparatus. The cement will flow through the packer apparatus and the float apparatus to fill the annulus between the casing and the wellbore.

This invention relates generally to methods and apparatus for cementing a casing in a wellbore, and more specifically is directed to methods and apparatus for utilizing float equipment inside casing used to drill a wellbore.
There are a variety of known methods for drilling wellbores to intersect with one or more hydrocarbon-producing formations for the production of oil and/or gas. One known procedure, and an increasingly common procedure for drilling a wellbore utilizes the casing string that will be cemented into the wellbore as the drill string. When a wellbore is drilled utilizing casing as the drill string, the wellbore is drilled to a desired depth, and the casing is typically pulled upwardly a distance from the bottom of the drilled wellbore. The drill bit on the lower end of the casing is then blown off using an explosive charge on a wireline, or is disconnected from the casing by other means known in the art.
Once the drill bit has been removed from the lower end of the casing, mud or other circulating fluids may be circulated through the casing. A bottom cementing plug can then be displaced into the casing ahead of the cement. The bottom cementing plug is allowed to pass through the open lower end of the casing and cement passes around the lower end of the casing upwardly into the annulus between the casing and the wellbore. Once the desired amount of cement has been displaced into the casing, a top cementing plug is placed in the casing behind the trailing edge of the cement. The top plug and the cement therebelow are urged downwardly in the casing by drilling mud or other known displacement fluids. Once the desired amount of cement has been placed in the annulus between the casing and the wellbore to cement the casing in the wellbore, which may occur either before or after the top cementing plug exits the casing, flow of the displacement fluid is stopped. Pressure is maintained utilizing a valve system at the surface, typically in connection with a plug container. Prior to conducting any further operations or procedures, it is generally necessary to wait several hours to insure that the cement is adequately set up prior to removing surface equipment, such as the plug container, and then reassembling the wellhead. Although such procedures exist for drilling with casing and then cementing the casing in a wellbore, the time loss is significant and costly. Thus, an improved apparatus and method for drilling with casing and cementing casing in a wellbore is needed.

Apparatus and method for drilling a wellbore with casing and cementing the casing in the wellbore


An improvement in internal cam rotary braiding machines wherein each lower carrier member thereof includes a plurality of oppositely disposed movably mounted and fixedly mounted pulleys used to convey a strand of material from a supply bobbin upwardly to the upper carrier members thereof, the pulleys being arranged to reduce the unwanted stresses which are normally imposed on the strand as it is conveyed upwardly over a deflector member and thence as it drops off the trailing edge of the deflector. Further structural improvements are made with respect to the spindle assembly used for the supply bobbin to reduce the normal movement, or "play," of the spindle assembly components during operation and, hence, to reduce further undesired stresses on the strand. The tension on the movably mounted pulleys can be adjusted to maintain a desired tension on the strand of material during the braiding operation to permit the braiding of very small filamentary materials with little or no breakage thereof during the braiding operation.

Braiding machines have long been known in the art for braiding multiple strands of materials, e.g., synthetic plastics or metals, such as copper or stainless steel wire, at reasonably high production rates. One type of braiding machine, which is commonly referred to as an internal cam rotary braider, has been known to the art for many years, being generally designated as the Wardwell Rapid Braider, made and sold by Wardwell Braiding Machine Company of Central Falls, R.I. (the "Wardwell" machine). Wardwell rotary braiding machines have been available in various sizes, depending on the number of strands required in the final braided output, and have been in use for many decades since the first designs thereof were made available about the turn of the century. Their reliability and relatively high speed of operation have been well recognized and such machines have been used satisfactorily over the years, normally requiring only the replacement of parts, their structure and operation having essentially remained unchanged since their original design.
As it becomes desirable, or necessary, to braid strands or filaments of material, particularly very fine copper or stainless steel wire materials, having extremely small diameters, e.g., as small as 0.0005-0.0030 inches, or less, it has been found that the Wardwell machine becomes unreliable because the rotary technique used therein produces so much tension on very small diameter materials, particularly at one stage of the braiding process, that such extremely fine filaments tend to break relatively easily and quickly, thereby automatically stopping the machine.
In an effort to braid such extremely fine filaments without significant breakage thereof, those in the art have turned to the use of other types of braiding machines, such as machines often ref erred to as "maypole" braiding machines, sold by the New England Butt Division of Wardwell Braiding Machine Company and by Steeger U.S.A., Inc. of Spartanburg, N.C., as well as machines often referred to as external cam rotary braiding machines, such as sold, for example, by Hacoba Textile Machinery of Charlotte, N.C. While such other types of machines tend to operate with some degree of success when used with relatively small diameter strands, the initial purchase and installation costs, as well as the operating costs thereof, tend to be higher than those of internal cam Wardwell machines, and the speeds of operation and, hence, the production rates thereof are often significantly lower than those of internal cam Wardwell machines.
It would be desirable, therefore, if the art could take advantage of the lower cost and higher operating speeds of the Wardwell rotating braiding machines by appropriately adapting such machines in a manner which would permit them to braid extremely fine materials without encountering the significant breakage problems discussed above and without unduly raising the costs of purchasing and operating such machines.