US 20070129630 A1
A method, device and system or kit treat a lesion by injecting a contrast agent into a body area to distinguish an osteolytic lesion for imaging; and delivering an effective amount of a debridement fluid to debride the distinguished lesion.
1. A method for treatment of a lesion, comprising:
injecting a contrast agent into a body area; and
allowing the contrast agent to migrate to an osteolytic lesion area to distinguish the osteolytic lesion for imaging.
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11. A system for treatment of a lesion, comprising:
a delivery device for injecting a contrast agent into a body area to distinguish an osteolytic lesion for imaging;
a fluid reservoir;
a debridement fluid contained within the fluid reservoir;
a tubular conduit having a pickup end and delivery/aspirator end and first and second cannulas extending with one another longitudinally as part of the tubular conduit; the first cannula having at least one orifice at the delivery/aspirator end of the tubular conduit to deliver or aspirate debridement fluid to or from the distinguished lesion; and the second cannula substantially open at the delivery/aspirator end of the tubular conduit to deliver or aspirate fluid to or from the distinguished lesion; and
an imaging device to monitor delivery of the debridement fluid to the distinguished lesion.
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29. A diagnostic procedure, comprising:
injecting a contrast agent into synovial fluid in a body area in need of treatment; and
imaging a location or extent of a lesion in the area that has been distinguished by the contrast agent.
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31. A method of imaging an osteolytic lesion, comprising:
injecting a contrast agent into synovial fluid in a vicinity of the osteolytic lesion;
permitting contrast agent injected synovial fluid to circulate to the lesion;
positioning an imaging device responsive to the contrast agent adjacent the vicinity of the osteolytic lesion; and
imaging the osteolytic lesion distinguished by the contrast agent from adjacent tissue.
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The invention relates generally to medical imaging and particularly to highlighting an osteolytic lesion and debridement of an imaged highlighted lesion. In an aspect, the invention relates to a method, device and kit for distinguishing and imaging a lesion for debridement.
Osteolysis is a common complication in total hip arthroplasty and the most common cause of component failure. Osteolysis is a response to wear debris. It can develop around a hip or knee implant as a result of generation of wear debris, access of the particles to the implant-bone interface and the biologic response of the implant host to the particles. Osteolysis is mediated primary by macrophages. Fibroblasts and endothelial cells also play a role. These cells are activated by the wear debris, primarily polyethylene, but also metal and polymethylmethacrylate particles. The biologic reaction to these particles is a nonspecific foreign-body reaction. Particles in the submicron size range undergo phagocytosis by macrophages and release a variety of cytokines which ultimately stimulate osteoclasts to resorb bone. The most common source of wear debris is adhesive-abrasive wear between a femoral head and polyethylene liner. This wear can produce as many as 500,000 particles per gait cycle.
Osteolysis can be asymptomatic until the lesions become very large. While some osteolytic lesions may be cleansed by washing and conventional debridement, surgery is a typical treatment. The surgery both treats the lesions and removes particles that could generate recurrence. With a stable acetabular component in acceptable alignment and with a modular liner, debridement and bone grafting of the lesions with retention of the acetabular shell and replacement of the polyethylene liner can be successful. However, if the acetabular shell is loose or malpositioned, then revision of the component is indicated.
While washing and debridement procedures are preferred approaches to lesion management, these less invasive procedures are not always available. First, osteolytic lesions are not easily diagnosed because they can be hidden well within tissue near an implant. They can be hidden from x-ray visualization because they are near obscuring metal implant structure or the like. Or, simply the lesions are not sufficiently distinguished from adjacent tissue and structure to be visualized by usual detection mechanisms such as fluoroscopy. Successful substantially noninvasive treatment of osteolytic lesions requires that the lesion location including location and extent in an implant area be identified and imaged during debridement. Currently there are few strategies for reliably noninvasively locating and identifying lesions for debridement. There is a need for a method, device and system or kit for diagnosing osteolytic lesions and for visualizing the location and extent of an osteolytic lesion.
The invention provides a method and kit for substantially noninvasively diagnosing an osteolytic lesion and a method and kit for distinguishing the location or extent of an osteolytic lesion for substantially noninvasively debridement of the lesion. According to the invention, a method for treatment of a lesion comprises: injecting a contrast agent into a body area to distinguish an osteolytic lesion for imaging; and delivering an effective amount of a debridement fluid to debride the distinguished lesion.
A system or kit for treatment of a lesion comprises: a delivery device for injecting a contrast agent into a body area to distinguish an osteolytic lesion for imaging; a fluid reservoir; a debridement fluid contained within the fluid reservoir; a tubular conduit having a pickup end and delivery/aspirator end and first and second cannulas extending with one another longitudinally as part of the tubular conduit; the first cannula having at least one orifice at the delivery/aspirator end of the tubular conduit to deliver or aspirate debridement fluid to or from the distinguished lesion; and the second cannula substantially open at the delivery/aspirator end of the tubular conduit to deliver or aspirate fluid to or from the distinguished lesion; and an imaging device to monitor delivery of the debridement fluid to the distinguished lesion.
In another embodiment, a diagnostic procedure comprises: injecting a contrast agent into synovial fluid in a body area in need of treatment; and imaging a location or extent of a lesion in the area that has been distinguished by the contrast agent.
In still another embodiment, a method of imaging an osteolytic lesion comprises injecting a contrast agent into synovial fluid in a vicinity of the osteolytic lesion; permitting contrast agent injected synovial fluid to circulate to the lesion; positioning an imaging device responsive to the contrast agent adjacent the vicinity of the osteolytic lesion; and imaging the osteolytic lesion distinguished by the contrast agent from adjacent tissue.
The invention relates to a method that injects a contrast agent, preferably water miscible, into a contained normal anatomic cavity of the body in the vicinity of an implant. In a preferred embodiment, a contrast agent is injected into synovial fluid at a joint. Synovial fluid is a clear, thixotropic lubricating fluid secreted by membranes in joint cavities, tendon sheaths, and bursae. The injected fluid carries a contrast agent that renders a lesion radio-opaque or identifiable to available non-invasive imaging technology. The injected material can distribute evenly within the cavity space by way of diffusion. The distribution can be enhanced by external ultrasound application, or mechanical motion of the cavity space. For example, after injection into a knee, a patient can be asked to walk a number of paces to help distribute the injected material.
In the case of a knee or hip replacement, lesions can form behind or around the implanted medical device. These lesions otherwise may be undetectable by conventional non-invasive imaging techniques. The injected contrast agent distributes within the fluid cavity. If a lesion communicates with the cavity, the material will also distribute to the previously un-identified lesion. The inventive method identifies a lesion that communicates with the fluid filled anatomic cavity, either by natural flow of the fluid around an implanted device or natural structure or through emplaced voids in a device such as the holes in an implanted cup. For example, osteolytic lesions can communicate with the normal anatomic synovial joint space either around an implant or through holes in a hip implant. According to the invention, the synovial fluid is injected with a contrast agent, which then flows to the lesion and distinguishes to make it identifiable by non-invasive imaging. The agent can identify the lesion location and extent to permit debridement.
Debridement can be by any suitable procedure for wound or lesion management including lavage, particularly pulse lavage or pulse irrigation is one. In pulse lavage, a pulsating water jet, is directed toward the wound or lesion area. This procedure is effective in removing debris and bacteria from wound and lesion areas. Pulse irrigation is used as part of a number of orthopedic procedures such as prosthetic joint replacement, in which it is used to remove bone fragments from an area of prosthesis.
The debridement fluid of the invention can be water and other aqueous compositions, including any other typical irrigating or debridement solution. Preferably the fluid is a clear biocompatible debridement fluid such as warm isotonic saline or normal saline in combination with an antibiotic. However, many variations are possible. The solution may include buffers and a bicarbonate, citric acid and tanic acid in very low concentrations. Or the fluid can be a gas and liquid mixture. The gas can be oxygen or carbon dioxide or hydrogen peroxide useful for sterilization purposes. The fluid can include steroid and anti-inflammatory mendicants.
A preferred debridement fluid comprises a mixture of inorganic salts and minerals, compounded to mimic an electrolyte concentration and a body fluid mixture in an isotonic state. The fluid typically comprises a halide salt of lithium, sodium, potassium, calcium, and other cations. Typically the halide is fluoride, chloride, bromide, or iodide, and most typically chloride. A typical electrolyzed solution has a pH within the range of about 2 to about 5, an oxidation reduction potential within the range of about +600 mV to about +1200 mV, and hypohalous acid concentration in the range of about 10 ppm to about 200 ppm. The solution can have bactericidal, fungicidal, and sporicidal properties.
In this specification, “biosorbable” means capable of being harmlessly taken up by the body and “biocompatible” means capable of harmlessly persisitng in the body. The term “biocomaptible” includes biosorbable materials. The debridement fluid of the invention can include a biocompatible particulate abrasive, which can be a biosorbable material that dissolves within several days. Preferably, the abrasive is biosorbable and capable of passing through small gauge needles under lavage pressure. Calcium sulfate (CaSO4) is a preferred material and may be obtained as MIIG™ from Wright Medical Technology, Inc. of Arlington, Tenn. The particulate abrasive can be present in the debridement fluid in a percent by weight between 0.1 and 65; desirably between 1 and 40 and preferably between 3 and 15. Other possible particulate abrasives include the materials disclosed in copending application, Shimko et al., (attorney docket P23148). For example, these include injectable forms of: calcium phosphate, tri-calcium phosphate, hydroxyapatite, coral hydroxyapatite, demineralized bone matrix, and mineralized bone matrix. Further, the biosorbable material can be an injectable solid form of a biopolymer, for example, polylactic acid, polyglycolic acid, polygalactic acid, polycaprolactone, polyethylene oxide, polypropylene oxide, polysulfone, polyethylene, polypropylene, hyaluronic acid or bioglass.
An embodiment of the invention comprises following progress of the lesion debridement by fluoroscopy. In this embodiment, contrast agent is injected into the lesion area through a catheter, or preferably through the inner expression cannula of the device of the invention along with debridement fluid. The contrast agent migrates so that the lesion can be radiographically imaged with a fluoroscope. The fluoroscope produces a planar (or two dimensional) image of the lesion area that can be evaluated to monitor the debridement method. This embodiment is discussed in further detail in conjunction with the drawings.
These and other features of the invention will become apparent from the drawings and following detailed discussion, which by way of example without limitation describe preferred embodiments of the invention.
In operation, a contrast agent is injected into the synovial fluid 228 by the injector 232. The contrast agent is delivered as a dissolved or suspended fluid that in turn is either dissolved or suspended in the synovial fluid 228 and is transported by the fluid 228 to the lesion 218, 220 site where it radio-opaquely contrasts the lesion 218, 220.
The contrasted lesions 218, 220, 248 and 252 are amenable to imaging diagnoses and fluoroscopic controlled debridement as described hereinafter with reference to
The contrast agent is a biocompatible material that is capable of being detected or monitored by fluoroscopy, x-ray photography, CAT scan, ultrasound or other such imaging techniques that can be used to detect and locate contrast distinguished tissue. The invention may be used as a diagnostic tool to identify and define previously unknown or undetected hard or soft orthopedic and skeletal lesions that communicate with normally occurring fluid filled anatomic spaces in the body, such as the synovial capsule surrounding articulating joints.
The contrast agent is suspended or dissolved into a carrying fluid and is injected into the vicinity of a joint implant with suspected osteolytic lesions. Preferred contrast agents are radio-opaque materials. The contrast agent can be either water soluble or water insoluble. Examples of water soluble contrast agents include metrizamide, iopamidol, iothalamate sodium, iodomide sodium, iohexol and meglumine. Examples of water insoluble contrast agents include tantalum, tantalum oxide, and barium sulfate, each of which is commercially available. Other water insoluble contrast agents include gold, tungsten, and platinum powders. Some radio-opaque contrasting agents are available in liquid form. These include, for example, OMNIPAQUE from Nycomed, Inc., Princeton, N.J. Preferably, the contrast agent is water insoluble (i.e., has a water solubility of less than 0.01 mg/ml at 20° C.).
The carrying fluid for the contrast agent can be water or other aqueous compositions. Preferably the fluid is a clear biocompatible fluid such as warm isotonic saline or normal saline. However, many variations are possible. The solution may include materials such as an antibiotic, a buffer or a bicarbonate, citric acid and tanic acid in very low concentrations.
As with the debridement fluid, a preferred carrying fluid comprises a mixture of inorganic salts and minerals, compounded to mimic an electrolyte concentration and a body fluid mixture in an isotonic state. The fluid typically comprises a halide salt of lithium, sodium, potassium, calcium, and other cations. Typically the halide is fluoride, chloride, bromide, or iodide, and most typically chloride. A typical electrolyzed solution has a pH within the range of about 2 to about 5, an oxidation reduction potential within the range of about +600 mV to about +1200 mV, and hypohalous acid concentration in the range of about 10 ppm to about 200 ppm. The solution can have bactericidal, fungicidal, and sporicidal properties.
The contrast agent can be dissolved or suspended in the carrying fluid in a weight percent from 0.001 mg/ml to 1000 mg/ml, desirably 0.01 mg/ml to 800 mg/ml, and preferably 0.1 mg/ml to 600 mg/ml.
The conduit 14 has a pickup end 16 at fluid reservoir 40 to operatively connect the inner cannula 18 from the reservoir 40 (through fluid transfer pump 50) to fluid aspirator/expression end 26 of rigid section 24. The outer aspirator cannula 20 is operatively connected from the fluid transfer pump 50 to fluid delivery/aspirator end 23 to fluid aspirator/discharge end 26 of rigid section 24. In this example, the fluid within the reservoir 40 is a saline solution. The saline solution comprises 10 weight percent suspended calcium sulfate particulate having a particle size of about 150 microns.
Fluid transfer pump 50 includes a drivable motor 52 having an elongated rotor shaft 54. A fluid pressure generating pump 58 is arranged at a first end 56 of the rotor shaft 54. The pump 58 provides fluid pressure to the dual cannula flexible tube 22 from reservoir 40. A second end 60 of rotatable shaft 54 is attached to a suction pump 62, also located within the housing 12. Suction pump is in fluid communication with a screened disposable collection bottle 34 to provide a vacuum incentive for drainage of fluids to the bag 34. In this embodiment, a common empowered motor 52 with an extended shaft 54 provides drive for both pressure pump 58 and vacuum source 62. The arrangement provides for a dual continuous pulsed feed of fluid to a patient lesion area shown in
In an embodiment shown in
First, referring to
Typical treatment to debride the lesion 218 is significant and invasive, sometimes involving removal of the implant 224, open debridement of the lesion 218 (which enlarges the intramedullary area even further), and implantation of a revision implant. In another typical treatment, location of the lesion 218 is identified by fluoroscope or other imaging process, first and second holes are bored to access the lesion area and lavage fluid is expressed through one hole and is suctioned out the second hold. This procedure operates blindly without assurance that fluid expressed through the first hole delivers lavage to the lesion area. Additionally, the lesion can be tough and resistant to a typical fluid that would be used in the first and second hole procedure.
The present invention provides a minimally-invasive and accurate approach to treating lesions without removal of implants and revision and without two hole bodily invasion. The invention accurately delivers lavage to assure complete debridement of the lesion. In the present invention, a lavage fluid is utilized that comprises abrasive particles that completely debride even an osteolytic lesion that may be filled with resistant gelatinous masses of nacrotic and fibrous tissue. Additionally, in an embodiment of the invention, insertion of the rigid delivery section 24 of the debridement device into the hip joint, the orientation of the syringe expressing end 70 of the delivery section 24; impingement of expressed debridement fluid the lesion and aspirating of fluid containing the nacrotic and fibrous tissue and spent fluid and particles can be monitored to assure complete debridement.
The lesion debridement is monitored in
In operation, patient 126 is aligned between tube unit 116 and image intensifier 148 so that the internal patient's hip joint 124 is visible on television monitor 116. User 112 performs a puncture of the patient's hip area toward the joint 124 with the elongated rigid delivery section 24 of debridement device 10. The user 112 positions the puncture so that the inserted delivery section 24 syringe end is generally perpendicular to a central axis of an x-ray beam, which is directed upward from fluoroscope x-ray tube unit 116 to image intensifier 148. The fluoroscopic field of view of fluoroscope 116 is then narrowed to display an image on monitor 116 to permit positioning aspirator/expression end 26 of delivery section 24 within the cancellous bone 134 of hip joint 124 at a location of the osteolytic lesion 136.
The user 112 manipulates the aspirator/expression end 26 of delivery section 24, while remaining outside of the path of the x-ray beam between x-ray tube unit 116 and image intensifier 148. as shown in
While preferred embodiments of the invention have been described, the present invention is capable of variation and modification and therefore should not be limited to the precise details of the above examples. For example, the invention relates to a kit that is packaged to include the above-described components for sale, shipment. The invention includes changes and alterations that fall within the purview of the following claims.