Introducers
"Numerous advances of considerable note have occurred in medical surgical techniques over the last few decades. Among the most significant advances has been the adoption, and now-routine performance, of a variety of minimally invasive procedures. Such procedures include angioplasty, endoscopy, laparoscopy, and arthroscopy, as well as numerous other diagnostic and therapeutic operations. These minimally invasive procedures can be distinguished from conventional open surgical procedures in that access to a site of concern within a patient is achieved through a relatively small incision, into which a tubular device (or tubular portion of a device) is inserted or introduced. (The Introducer) The tubular device, or device portion, keeps the incision open while permitting access to the target site via the interior (i.e., the lumen) of the tube."
"Body passageways in which introducer apparatuses have been used to introduce medical interventional devices and/or liquid medicaments include the esophagus, trachea, colon, biliary tract, urinary tract, and virtually all portions of the vascular system, among others. One particularly significant example of a minimally invasive technique involves the temporary or permanent implantation of a medical interventional device, such as a stent, into a body passageway of a patient. Other examples involve the transmission of a liquid medicament to a target area, and/or the withdrawal of body fluid from the body passageway."
"When carrying out these, and other, desired techniques, communication with the passageway is typically attained by inserting an access device, such as an introducer sheath, into the body passageway. One typical procedure for inserting the introducer sheath is the well-known Seldinger percutaneous entry technique. In the Seldinger technique, a needle is initially injected into the passageway, such as a vessel, and a wire guide is inserted into the vessel through a bore of the needle. The needle is withdrawn, and an introducer assembly is inserted over the wire guide into the opening in the vessel."
"Typically, the introducer assembly includes an outer introducer sheath, and an inner dilator having a tapered distal end. The tapered end of the dilator stretches the opening in the vessel in controlled fashion, so that introduction of the larger diameter introducer sheath may then be carried out with a minimum of trauma to the patient. Following satisfactory placement of the introducer sheath, the dilator is removed, leaving at least the distal portion of the larger diameter introducer sheath in place in the vessel. The interventional device, such as a stent, etc., or the liquid medicament may then be passed through the introducer sheath for delivery to the target site."
Recent US Patents
10/19/2010
7,815,762
Method of forming an introducer sheath
Lentz and Howat of Cook Incorporated , Indiana formed an introducer sheath having a crease-free tapered distal tip portion. They used a mandrel with an elongated body and a tapered distal tip portion. An inner liner tube of heat shrinkable PTFE, is positioned over the mandrel. The inner liner is heat shrunk to the outer configuration of the mandrel, in a manner that avoids the formation of creases along the inner diameter of the liner. A reinforcing member is positioned over a length of the inner liner, and an outer jacket is positioned over the reinforcing member and the inner liner. (RDC 1/24/2011)
