News Column

Patent Issued for Medical Device Anchor and Method of Manufacture

May 28, 2014



By a News Reporter-Staff News Editor at Journal of Engineering -- From Alexandria, Virginia, VerticalNews journalists report that a patent by the inventor Olson, Robert L. (Vadnais Heights, MN), filed on August 21, 2009, was published online on May 13, 2014.

The patent's assignee for patent number 8721598 is Medtronic, Inc. (Minneapolis, MN).

News editors obtained the following quote from the background information supplied by the inventors: "Medical electrical leads or drug delivery catheters (hereafter referred to as therapy devices) are placed in the contact with biological tissue to delivery a therapy to the patient. These therapy devices are part of a system that may include signal or implantable pulse generators (IPGs) or drug delivery pumps or combinations of such. The stimulators or pumps in the system may be external to, or implanted in, the patient.

"Medical electrical leads may be used, for example, to delivery electrical energy to various biological tissues such as the heart, brain, or peripheral nervous system, etc. For example, implantable leads, such as the Medtronic Model 3487A lead, have been used for stimulating the dorsal columns of the spinal cord, or implantable leads, such as the Medtronic Model 3587A, have been used for peripheral nerve stimulation.

"Medical drug delivery catheters, for example, may be used to delivery therapeutic agents to the intrathecal space of the spinal canal, or to the blood vasculature, or brain ventricles, etc. Catheters such as the Medtronic Model 8703 may be used for these types of applications.

"Retention devices, typically referred to as anchors, are utilized to secure these leads and catheters thereby prevent lead or catheter movement or migrations. U.S. Pat. No. 5,843,146, which is assigned to Medtronic, discloses a medical lead anchor for anchoring a medical lead relative to, for example, the epidural space of the spinal cord.

"Another such anchor is the Medtronic Model 3550 EZ Anchor. This anchor consisted of a molded elastomer, e.g., medical grade silicone rubber, suitable for long-term implantation into a patient. The surface of the Model 3550 EZ Anchor is covered with a pattern of bumps. The bumps allow sutures to be placed in a constricting manner around the midportion of the anchor.

"Yet another example is U.S. Pat. No. 4,553,961 (Pohndorf et al), which is entitled 'suture sleeve with structure for enhancing pacing lead gripping.' One of the embodiments of the suture sleeve of the Pohndorf et al '961 patent includes a gripping enhancing structure, which comprises a framework of an undulating or sinuous, continuous rib including axially extending segments, or simply axial segments, and short partially circular segments, or simply short circular segments. Each short circular segment connects an adjacent pair of axial segments at one end of the framework. Each axial segment of the sinuous rib is spaced an equal distance from each of the adjacent axial segments and this formation purportedly allows for compressibility of framework against a lead body. The short circular segments of the Pohndorf et al '961 patent are shown as being at the same radial distance or position relative to the through-bore of the suture sleeve."

As a supplement to the background information on this patent, VerticalNews correspondents also obtained the inventor's summary information for this patent: "As used herein, the term, 'exemplary' is used in the sense of 'for example' or 'for purposes of illustration,' and not in a limiting sense.

"An exemplary medical device anchor is adapted to prevent or resist therapy device migration after the implantation of leads or catheters in a patient. Implantable neurostimulation systems are exemplified in this application for purposes of illustration, but one skilled in the art would realize that the concepts presented would be applicable to other medical devices such as heart pacemaker and defibrillators as well as drug delivery devices and methods.

"Exemplary embodiments of the medical device anchor provide: 1) secure lead or catheter retention by compression of beams or linked beams, 2) positive fixation of the gripping element or structure within a soft body of the medical device anchor, 3) unrestricted suture location within a suture zone of the anchor body, 4) soft, flexible tips minimizing or reducing tissue interactions.

"A first exemplary embodiment is a medical device anchor that generally comprises a gripping structure and a body portion. The gripping structure has a generally tubular configuration defining axial and radial directions. The gripping structure being defined or formed by an annular shoulder and a plurality of compressible beams extending axially from the annular shoulder wherein the shoulder extends radially outwardly beyond the beams. The body portion is formed by molding around the gripping structure and retains the shoulder within the body portion. The gripping means and body portion define a lumen extending in the axial direction for receiving a lead or catheter.

"A second exemplary embodiment is a medical device anchor that generally comprises a gripping structure and a body portion. The gripping structure forms or defines a through hole having a circumference, wherein axial, circumferential and radial directions are defined relative to the through hole. The gripping structure is formed by a plurality of compressible axial segments, a plurality of shoulder segments and a plurality of bridging segments. The plurality of compressible axial segments are arranged in a generally parallel, spaced apart array along the circumference of the through hole, with each axial segment having first and second ends. The plurality of shoulder segments area separated from one another in alternating fashion by a plurality of shoulder gaps forming a generally annular array of shoulder segments and shoulder gaps, with the first ends of the axial segments being alternately bridged or unbridged by the shoulder segments and shoulder gaps. The shoulder segments extend radially outward relative to the through hole further than the axial segments. The plurality of bridging segments are separated from one another in alternating fashion by a plurality of unbridged gaps forming a generally annular array of bridging portions and unbridged gaps, with the second ends of the axial segments being alternately bridged or unbridged by the bridging segments and unbridged gaps such that the gripping structure forms a serpentine arrangement of a continuous nature with the axial segments alternately interconnected between shoulder segments and bridging segments. The body portion is formed by molding to retain the shoulders within the body portion, the gripping structure and body portion defining a lumen for receiving a lead or catheter.

"A third exemplary embodiment is a suture sleeve assembly comprising a suture sleeve made of soft elastomeric material and means associated with the suture sleeve for enhancing gripping of a lead body by the suture sleeve. The suture sleeve comprises a tubular sleeve having a throughbore adapted to receive a lead body or catheter. The gripping enhancing means is made of a material that is different than the material of the suture sleeve and which is stiff but flexible, and the gripping enhancing means is positioned to extend within and longitudinally of an elongate axis of the suture sleeve in a suture-receiving area of the suture sleeve intended to receive one or more sutures thereby to disperse any stress placed upon said suture sleeve when sutures are tied along the suture-receiving area. The suture sleeve assembly is radially compressible upon the placement and tying of a suture around the suture sleeve assembly in the suture-receiving area to facilitate generally uniform gripping of the lead body or catheter by the suture sleeve assembly along the length of the gripping enhancing means. The gripping enhancing means comprises a cylindrical flexible framework within a suture sleeve forming a cylindrical envelope. The framework is defined by an undulating or sinuous arrangement of a continuous rib extending in axial segments connected by arcuate segments wherein the arcuate segments define two shoulders extending radially outwardly relative to the through bore farther than the axial segments, and the two shoulders define the suture-receiving area.

"A fourth exemplary embodiment is a method of manufacturing the medical device anchor generally comprising forming a gripping structure of the type described above in which the shoulder segments extend radially outward relative to the through hole farther than the axial segments, and molding a body portion on the gripping structure to securely capture the shoulder in the body portion, the body portion being molded of material that is softer and more compliant than the gripping structure.

"A fifth exemplary embodiment is a method of manufacturing the medical device anchor generally comprising forming a gripping structure of the type described above in which the shoulder segments extend radially outward relative to the through hole farther than the axial segments, and stretching a body portion on the gripping structure with the shoulder segments securely captured by the body portion, the body portion being molded of material that is softer and more compliant than the gripping structure."

For additional information on this patent, see: Olson, Robert L.. Medical Device Anchor and Method of Manufacture. U.S. Patent Number 8721598, filed August 21, 2009, and published online on May 13, 2014. Patent URL: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=107&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=5332&f=G&l=50&co1=AND&d=PTXT&s1=20140513.PD.&OS=ISD/20140513&RS=ISD/20140513

Keywords for this news article include: Therapy, Medtronic Inc., Drug Delivery Systems.

Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC


For more stories covering the world of technology, please see HispanicBusiness' Tech Channel



Source: Journal of Engineering


Story Tools






HispanicBusiness.com Facebook Linkedin Twitter RSS Feed Email Alerts & Newsletters