摘要:
A heart valve prosthesis and a method of fabricating the same. The heart valve prosthesis uses a leaflet of pig pericardium or a leaflet of cattle pericardium, which has a suitable thickness according to the size of the valve, and a stent. The heart valve prosthesis is fabricated by placing a valve body over a Dacron body, binding the valve body to the Dacron body using stitching fiber, rolling the Dacron body into a cylindrical form such that the valve body is located inside, binding opposite edges of the Dacron body to each other using stitching fiber, and inserting the resultant structure into a stent, which is knitted using a shape memory alloy wire. The heart valve prosthesis is friendly to and is not rejected by human tissue, is free from deformation, and can be implanted using a non-invasive manner without incising the chest wall of a patient.
摘要:
Disclosed herein is a stent for prostatic urethra expansion which does not generate bladder stones, is removable without causing injury on a urethra, and does not generate atrophy of a prostatic urethra even after removal. The stent for prostatic urethra expansion include a stent unit including a cylindrical body with space parts formed by knotting or crossing shape memory alloy wires and bending terminals formed at both ends of the cylindrical body, a pair of hook wires passing through the space parts and knotted to the shape memory alloy wires, both ends thereof being wound on the bending terminals and then being bent upwardly to produce hooks, and a pair of hanging strings arranged in opposite directions to form a hanging knot. The stent for prostatic urethra expansion does not move into the bladder, and expands and maintains a lumen of the stenosed prostatic urethra, thereby reducing post-operative recovery time.
摘要:
A wavily deformable stent includes a hollow cylindrical net body formed of elastically deformable wires interlaced with each other. The net body extends in a longitudinal direction and terminates at open opposite ends. The net body has at least one high-rigidity section and at least one low-rigidity section less rigid than the high-rigidity section. The high-rigidity section and the low-rigidity section are arranged continuously and alternately along the longitudinal direction. The stent is wavily deformed and held in place against unwanted displacement when situated inside a stenosed part of a bodily organ. Also provided is a method for producing the wavily deformable stent.
摘要:
A partially biodegradable stent includes a main net body of hollow cylindrical shape formed of elastically deformable wires interlaced with each other, the net body extending in a longitudinal direction and terminating at open opposite ends, and an auxiliary net portion provided at one of the open opposite ends of the main net body, the auxiliary net portion formed of a biodegradable wire which can be degraded and removed by a bodily fluid. The auxiliary net portion is formed by interlacing the biodegradable wire into a cylindrical shape independently of the main net body or by interlacing the biodegradable wire with the elastically deformable wires at one of the open opposite ends of the main net body.
摘要:
Disclosed herein is a stent for connecting adjacent tissues of the organs of a patient. The stent includes a hollow cylindrical body which is formed by weaving a superelastic shape-memory alloy wire in an overlapping manner such that rhombic openings are formed, and wing parts which are provided by expanding respective opposite ends of the hollow cylindrical body outwards and turning the opposite ends inside out on bent portions. The wing parts face each other so that the wing parts are tensed in a longitudinal direction of the cylindrical body. Thereby, the wing parts can elastically move inwards or outwards with respect to the longitudinal direction to automatically adjust a distance between the wing parts in response to the distance between the adjacent tissues of the organs or thicknesses of walls of the organs, so that the wing parts are put into close contact with the adjacent tissues.
摘要:
This invention relates to a method of manufacturing a coating agent for a drug releasing stent and to a coating agent for a drug releasing stent manufactured thereby. This method includes (1) dissolving polyurethane in tetrahydrofuran, (2) dissolving pluronic F-127 in tetrahydrofuran, (3) dissolving a gemcitabine compound in ethanol, (4) mixing these three solutions obtained in (1) to (3) thus preparing a solution mixture, (5) applying the solution mixture obtained in (4) on a stent coated with a Teflon film, (6) drying the stent of (5) for a predetermined period of time and then immersing the stent in a polyurethane solution in tetrahydrofuran, and (7) removing the stent immersed in (6) from the polyurethane solution and then drying the stent, so that the rate of release of an anti-cancer drug applied on the stent can be continuously and maximally improved thereby maximizing anti-cancer efficacy.
摘要:
A biodegradable double stent is used for various organs such as a biliary tract, an esophagus, an airway and a ureter. A biodegradable stent having a hollow cylindrical body woven out of a separate wire made of biodegradable polymer so as to have a plurality of rhombic spaces is fixed to an intermediate portion of a primary stent having a cylindrical body. When administered into the organ, the biodegradable stent has its original function of expanding the organ, and is firmly supported in the inner wall of a narrowed passage of the organ by pressurizing the inner wall of the narrowed passage of the organ. After a predetermined time period has elapsed, the biodegradable stent is gradually degraded away by bodily fluids, thereby enabling the primary stent to be easily removed from the organ.
摘要:
Disclosed herein are a plastic stent and a stent operation apparatus for plastic stents. The plastic stent includes a stent body with a flow hole formed through the stent body in the longitudinal direction thereof. The stent operation apparatus includes a stent push rod having an externally threaded end. The stent body has an internal thread on the circumferential inner surface of the flow hole so that the internal thread engages with the externally threaded end of the stent push rod of the stent operation apparatus. The plastic stent is coupled to the stent push rod by the threaded engagement between the externally threaded end and the internal thread, is inserted into the body of a patient, is adjusted in location by pushing or pulling the stent push rod, and is released from the stent push rod at a correct location in the body of the patient by disengaging the threaded engagement.
摘要:
Disclosed herein is the resonant inverter of a radio frequency (RF) generator for radiofrequency ablation (RFA). The resonant inverter of RF generator for RFA amplifies to high power an oscillation frequency output from an oscillator and provides the amplified oscillation frequency to an electrode. The resonant inverter processes the oscillation frequency output from the oscillator as a high-power sine wave having a frequency of 480 kHz and a Root Mean Square (RMS) power of 30 to 200 watts, and transfers the high-power sine wave to the electrode.
摘要:
If smooth transportation of bile toward the duodenum is difficult due to cancerous cells growing in the bile duct or due to stricture of the bile duct, a cylindrical stent may be implanted into the stenosed site of the bile duct to enable smooth supply of bile. Conventional stents have no risk of slippage at an implanted position thereof, but suffer from invasively growing cancerous cells. Although a covered stent having a coating has been proposed to solve invasion of the growing cancerous cells, the covered stent may have a risk of slippage at an implanted position thereof and also, may cause pancreatitis and cholelithiasis. To solve the above described problems, disclosed herein is a stent to prevent backflow of food from the duodenum to the bile duct while assuring smooth transportation of bile without a risk of unwanted displacement caused by the transported bile. The stent includes a cylindrical outer stent, and a downwardly tapered inner stent covered with a polytetrafluoroethylene (PTFE) or silicone coating having biocompatibility. The inner and outer stents are coupled to each other to define a double structure.