Abstract: A tissue sampling instrument or device for use with a two-part needle assembly having an outer cannula and an inner stylet, includes first and second carriage structures for displacing the respective stylet and cannula. The instrument also includes a drive carriage structure which provides separate and sequential engagement and displacement of the two needle carriage structures during operation of the instrument. The drive carriage structure first engages and displaces the stylet carriage, and thereafter engages and displaces the cannula carriage in order to produce sequential motions of the stylet and cannula in the operation to capture the tissue sample. The drive carriage structure also includes means for releasing the engagement of the stylet carriage at the termination of its driven displacement prior to the sequentially successive engagement of the cannula carriage structure.
Type:
Grant
Filed:
March 16, 1990
Date of Patent:
June 16, 1992
Assignees:
Ryder International Corporation, Meadox Medicals, Inc.
Abstract: A collagen-impregnated vascular graft includes a porous synthetic vascular graft substrate formed by knitting or weaving with at least three applications of dispersed collagen fibrils. Plasticizers are incorporated into the collagen slurry before application and the slurry is applied in separate treatments by massage and flow through techniques, cross-linked by exposure to formaldhyde vapor and dried.
Abstract: A dilatation catheter having an outer tubular balloon portion with length-wise circumferential crimps having at either end transition portions with longitudinal crimps across the axis and an inner catheter is provided. The distal transition portion is fastened to the distal end of the inner catheter tube which extends beyond the distal end of the outer tube and the balloon portion while the proximal transition portion is connected to the distal end of the outer catheter tube. The balloon portion expands readily to a predetermined diameter while undergoing little change in length with an extension of the transition portions so that relative movement of the inner and outer catheter tubing is not required. Accordingly, minimum shear forces occur at the interface of the expanded balloon surface and the interior vessel wall.
Abstract: A dilatation catheter having an outer tubular balloon portion with length-wise circumferential crimps having at either end transition portions with longitudinal crimps across the axis and an inner catheter is provided. The distal transition portion is fastened to the distal end of the inner catheter tube which extends beyond the distal end of the outer tube and the balloon portion while the proximal transition portion is connected to the distal end of the outer catheter tube. The balloon portion expands readily to a predetermined diameter while undergoing little change in length with an extension of the transition portions so that relative movement of the inner and outer catheter tubing is not required. Accordingly, minimum shear forces occur at the interface of the expanded balloon surface and the interior vessel wall.
Abstract: A collagen impregnated synthetic vascular graft including a synthetic vascular graft substrate and cross-linked collagen fibril is formed by depositing an aqueous slurry of collagen fibrils in the lumen of the graft and massaging to insure intimate mixing of the fibrils into the porous structure of the substrate. After massaging, the collagen is dried and cross-linked. Repeated applications and massaging and drying further reduce porosity of the graft.
Abstract: A woven double-velour fabric of synthetic fiber provides an excellent structure for ingrowth and adhesion of tissue thereto and can be woven tightly enough so that preclotting may be omitted is so desired. The features recited are achieved through the use of appropriate combinations of preshrunk, texturized yarn with unshrunk, untexturized yarn.
Abstract: A high-strength ligament prosthesis having biological acceptability, flexibility, porosity and resistance to prolonged stress in excess of 100 Kg with little change in modulus, and less than 20% ultimate elongation is provided. These characteristics make the high-strength prosthesis favorable for critical applications, such as knee and ankle repair. The high-strength prosthesis is constructed of a biological compatible yarn having an outer shell with an "H-beam" cross-section and a velour surface to encourage rapid invasion by host tissue and a reinforcing core of the same yarn. The ends of the reinforcing core and outer wall are fitted with end tips to limit displacement of the core within the outer shell and to facilitate positioning of the prosthesis during surgery with minimal effort. An enlarged elongated end tip is particularly well adapted for special surgical procedures, such as arthoscopic procedures.
Type:
Grant
Filed:
August 21, 1981
Date of Patent:
November 20, 1984
Assignee:
Meadox Medicals, Inc.
Inventors:
Harmon L. Hoffman, Jr., Steven Weinberg, John P. Park
Abstract: Prosthesis suitable for replacing or supplementing damaged ligaments or tendons are prepared from polyethylene terephthalate strips by treating such strips with a shrinking agent under restraint in the longitudinal direction. The treatment reduces substantially the extensibility of the fabric in the longitudinal direction. Stiffness can be imparted to the strips by forming the strips into tubes which may have longitudinally-extending ridges thereon and heat-setting same.
Abstract: A warp-knitted fabric has pile loops on both faces thereof. The loops on both faces are continuous with each other so that when the fabric is used as a prosthesis, growth of tissue from one face to the other is facilitated. This feature is particularly significant when the fabric is fashioned into tubular form, whether straight or bifurcated. The structure of the fabric is such that a desired degree of rigidity is obtained with a thinner fabric than has hitherto been the case.
Abstract: A double-velour vascular graft has a tubular body or trellis with loops projecting both outwardly and inwardly from said trellis. The loops on both the inner and outer surfaces of the trellis provide for more effective preclotting and ingrowth of tissue without impeding the flow of blood through the tubular body. The graft is produced on a double-needle bar warp-knitting machine using two outside beams and two inside beams, the beams feeding yarn for the loops to said knitting machine at a greater rate than the beams feeding yarn for the trellis.
Abstract: Polyester fabric which may be in the form of a warp-knitted lock-stitched or tricot-stitched tubular construction is compacted by treatment with NO.sub.2 either in the gaseous phase or in solution. The product, after neutralization, washing and crimping is suitable for vascular prostheses. In one form, the compacted product is crimped and bifurcated. Shrinkage in both the longitudinal and transverse directions is at least 30%. The porosity of the fabric is reduced by the compacting treatment.
Abstract: A synthetic vascular graft composed of fine denier polyester fiber forming a warp-knitted tube. The vascular graft has a porosity sufficient for optimum tissue ingrowth characteristics while at the same time retaining sufficient control of porosity to prevent hemorrhage at the time of implantation. The tubular vascular graft is knitted on a double needle bar warpknitting Raschel machine preferably with a tricot stitch and with the knitted structure having on the order of a 56 gauge.