Polytetrafluoroethylene: Homopolymer of tetrafluoroethylene. Nonflammable, tough, inert plastic tubing or sheeting; used to line vessels, insulate, protect or lubricate apparatus; also as filter, coating for surgical implants or as prosthetic material. Synonyms: Fluoroflex; Fluoroplast; Ftoroplast; Halon; Polyfene; PTFE; Tetron.Blood Vessel Prosthesis: Device constructed of either synthetic or biological material that is used for the repair of injured or diseased blood vessels.Polyethylene Terephthalates: Polyester polymers formed from terephthalic acid or its esters and ethylene glycol. They can be formed into tapes, films or pulled into fibers that are pressed into meshes or woven into fabrics.Vascular Patency: The degree to which BLOOD VESSELS are not blocked or obstructed.Blood Vessel Prosthesis Implantation: Surgical insertion of BLOOD VESSEL PROSTHESES to repair injured or diseased blood vessels.Arteriovenous Shunt, Surgical: Surgical shunt allowing direct passage of blood from an artery to a vein. (From Dorland, 28th ed)Popliteal Artery: The continuation of the femoral artery coursing through the popliteal fossa; it divides into the anterior and posterior tibial arteries.Graft Occlusion, Vascular: Obstruction of flow in biological or prosthetic vascular grafts.Femoral Artery: The main artery of the thigh, a continuation of the external iliac artery.Anastomosis, Surgical: Surgical union or shunt between ducts, tubes or vessels. It may be end-to-end, end-to-side, side-to-end, or side-to-side.Prostheses and Implants: Artificial substitutes for body parts, and materials inserted into tissue for functional, cosmetic, or therapeutic purposes. Prostheses can be functional, as in the case of artificial arms and legs, or cosmetic, as in the case of an artificial eye. Implants, all surgically inserted or grafted into the body, tend to be used therapeutically. IMPLANTS, EXPERIMENTAL is available for those used experimentally.Coated Materials, Biocompatible: Biocompatible materials usually used in dental and bone implants that enhance biologic fixation, thereby increasing the bond strength between the coated material and bone, and minimize possible biological effects that may result from the implant itself.Prosthesis Design: The plan and delineation of prostheses in general or a specific prosthesis.Fluorocarbon PolymersTissue Adhesions: Pathological processes consisting of the union of the opposing surfaces of a wound.Biocompatible Materials: Synthetic or natural materials, other than DRUGS, that are used to replace or repair any body TISSUES or bodily function.Suture Techniques: Techniques for securing together the edges of a wound, with loops of thread or similar materials (SUTURES).Saphenous Vein: The vein which drains the foot and leg.Polyurethanes: A group of thermoplastic or thermosetting polymers containing polyisocyanate. They are used as ELASTOMERS, as coatings, as fibers and as foams.Jugular Veins: Veins in the neck which drain the brain, face, and neck into the brachiocephalic or subclavian veins.Tibial Arteries: The anterior and posterior arteries created at the bifurcation of the popliteal artery. The anterior tibial artery begins at the lower border of the popliteus muscle and lies along the tibia at the distal part of the leg to surface superficially anterior to the ankle joint. Its branches are distributed throughout the leg, ankle, and foot. The posterior tibial artery begins at the lower border of the popliteus muscle, lies behind the tibia in the lower part of its course, and is found situated between the medial malleolus and the medial process of the calcaneal tuberosity. Its branches are distributed throughout the leg and foot.Surgical Mesh: Any woven or knit material of open texture used in surgery for the repair, reconstruction, or substitution of tissue. The mesh is usually a synthetic fabric made of various polymers. It is occasionally made of metal.Seroma: Tumor-like sterile accumulation of serum in a tissue, organ, or cavity. It results from a tissue insult and is the product of tissue inflammation. It most commonly occurs following MASTECTOMY.Veins: The vessels carrying blood away from the capillary beds.Reoperation: A repeat operation for the same condition in the same patient due to disease progression or recurrence, or as followup to failed previous surgery.Sutures: Materials used in closing a surgical or traumatic wound. (From Dorland, 28th ed)Hyperplasia: An increase in the number of cells in a tissue or organ without tumor formation. It differs from HYPERTROPHY, which is an increase in bulk without an increase in the number of cells.Vascular Grafting: Surgical insertion of BLOOD VESSEL PROSTHESES, or transplanted BLOOD VESSELS, or other biological material to repair injured or diseased blood vessels.Fibrin Tissue Adhesive: An autologous or commercial tissue adhesive containing FIBRINOGEN and THROMBIN. The commercial product is a two component system from human plasma that contains more than fibrinogen and thrombin. The first component contains highly concentrated fibrinogen, FACTOR VIII, fibronectin, and traces of other plasma proteins. The second component contains thrombin, calcium chloride, and antifibrinolytic agents such as APROTININ. Mixing of the two components promotes BLOOD CLOTTING and the formation and cross-linking of fibrin. The tissue adhesive is used for tissue sealing, HEMOSTASIS, and WOUND HEALING.Femoral Vein: The vein accompanying the femoral artery in the same sheath; it is a continuation of the popliteal vein and becomes the external iliac vein.Dura Mater: The outermost of the three MENINGES, a fibrous membrane of connective tissue that covers the brain and the spinal cord.Iliac Artery: Either of two large arteries originating from the abdominal aorta; they supply blood to the pelvis, abdominal wall and legs.Arterial Occlusive Diseases: Pathological processes which result in the partial or complete obstruction of ARTERIES. They are characterized by greatly reduced or absence of blood flow through these vessels. They are also known as arterial insufficiency.Axillary Artery: The continuation of the subclavian artery; it distributes over the upper limb, axilla, chest and shoulder.Catheters, Indwelling: Catheters designed to be left within an organ or passage for an extended period of time.Materials Testing: The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.Silicone Elastomers: Polymers of silicone that are formed by crosslinking and treatment with amorphous silica to increase strength. They have properties similar to vulcanized natural rubber, in that they stretch under tension, retract rapidly, and fully recover to their original dimensions upon release. They are used in the encapsulation of surgical membranes and implants.Postoperative Complications: Pathologic processes that affect patients after a surgical procedure. They may or may not be related to the disease for which the surgery was done, and they may or may not be direct results of the surgery.Tunica Intima: The innermost layer of an artery or vein, made up of one layer of endothelial cells and supported by an internal elastic lamina.Renal Dialysis: Therapy for the insufficient cleansing of the BLOOD by the kidneys based on dialysis and including hemodialysis, PERITONEAL DIALYSIS, and HEMODIAFILTRATION.Hernia, Ventral: A hernia caused by weakness of the anterior ABDOMINAL WALL due to midline defects, previous incisions, or increased intra-abdominal pressure. Ventral hernias include UMBILICAL HERNIA, incisional, epigastric, and spigelian hernias.Polypropylenes: Propylene or propene polymers. Thermoplastics that can be extruded into fibers, films or solid forms. They are used as a copolymer in plastics, especially polyethylene. The fibers are used for fabrics, filters and surgical sutures.Aorta, Abdominal: The aorta from the DIAPHRAGM to the bifurcation into the right and left common iliac arteries.Life Tables: Summarizing techniques used to describe the pattern of mortality and survival in populations. These methods can be applied to the study not only of death, but also of any defined endpoint such as the onset of disease or the occurrence of disease complications.Ischemia: A hypoperfusion of the BLOOD through an organ or tissue caused by a PATHOLOGIC CONSTRICTION or obstruction of its BLOOD VESSELS, or an absence of BLOOD CIRCULATION.Abdominal Wall: The outer margins of the ABDOMEN, extending from the osteocartilaginous thoracic cage to the PELVIS. Though its major part is muscular, the abdominal wall consists of at least seven layers: the SKIN, subcutaneous fat, deep FASCIA; ABDOMINAL MUSCLES, transversalis fascia, extraperitoneal fat, and the parietal PERITONEUM.Membranes, Artificial: Artificially produced membranes, such as semipermeable membranes used in artificial kidney dialysis (RENAL DIALYSIS), monomolecular and bimolecular membranes used as models to simulate biological CELL MEMBRANES. These membranes are also used in the process of GUIDED TISSUE REGENERATION.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Hemostasis, Surgical: Control of bleeding during or after surgery.Thrombosis: Formation and development of a thrombus or blood clot in the blood vessel.Transducers, Pressure: Transducers that are activated by pressure changes, e.g., blood pressure.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Alloys: A mixture of metallic elements or compounds with other metallic or metalloid elements in varying proportions.Leg: The inferior part of the lower extremity between the KNEE and the ANKLE.Stents: Devices that provide support for tubular structures that are being anastomosed or for body cavities during skin grafting.Vascular Surgical Procedures: Operative procedures for the treatment of vascular disorders.Chordae Tendineae: The tendinous cords that connect each cusp of the two atrioventricular HEART VALVES to appropriate PAPILLARY MUSCLES in the HEART VENTRICLES, preventing the valves from reversing themselves when the ventricles contract.Inguinal Canal: The tunnel in the lower anterior ABDOMINAL WALL through which the SPERMATIC CORD, in the male; ROUND LIGAMENT, in the female; nerves; and vessels pass. Its internal end is at the deep inguinal ring and its external end is at the superficial inguinal ring.Limb Salvage: An alternative to amputation in patients with neoplasms, ischemia, fractures, and other limb-threatening conditions. Generally, sophisticated surgical procedures such as vascular surgery and reconstruction are used to salvage diseased limbs.Dogs: The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)Follow-Up Studies: Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.Superior Vena Cava Syndrome: A condition that occurs when the obstruction of the thin-walled SUPERIOR VENA CAVA interrupts blood flow from the head, upper extremities, and thorax to the RIGHT ATRIUM. Obstruction can be caused by NEOPLASMS; THROMBOSIS; ANEURYSM; or external compression. The syndrome is characterized by swelling and/or CYANOSIS of the face, neck, and upper arms.Amputation: The removal of a limb or other appendage or outgrowth of the body. (Dorland, 28th ed)Aneurysm: Pathological outpouching or sac-like dilatation in the wall of any blood vessel (ARTERIES or VEINS) or the heart (HEART ANEURYSM). It indicates a thin and weakened area in the wall which may later rupture. Aneurysms are classified by location, etiology, or other characteristics.Implants, Experimental: Artificial substitutes for body parts and materials inserted into organisms during experimental studies.Papio: A genus of the subfamily CERCOPITHECINAE, family CERCOPITHECIDAE, consisting of five named species: PAPIO URSINUS (chacma baboon), PAPIO CYNOCEPHALUS (yellow baboon), PAPIO PAPIO (western baboon), PAPIO ANUBIS (or olive baboon), and PAPIO HAMADRYAS (hamadryas baboon). Members of the Papio genus inhabit open woodland, savannahs, grassland, and rocky hill country. Some authors consider MANDRILLUS a subgenus of Papio.Axillary Vein: The venous trunk of the upper limb; a continuation of the basilar and brachial veins running from the lower border of the teres major muscle to the outer border of the first rib where it becomes the subclavian vein.Constriction, Pathologic: The condition of an anatomical structure's being constricted beyond normal dimensions.Endarterectomy, Carotid: The excision of the thickened, atheromatous tunica intima of a carotid artery.Knee: A region of the lower extremity immediately surrounding and including the KNEE JOINT.Heart-Lung Machine: Apparatus that provides mechanical circulatory support during open-heart surgery, by passing the heart to facilitate surgery on the organ. The basic function of the machine is to oxygenate the body's venous supply of blood and then pump it back into the arterial system. The machine also provides intracardiac suction, filtration, and temperature control. Some of the more important components of these machines include pumps, oxygenators, temperature regulators, and filters. (UMDNS, 1999)Foreign-Body Reaction: Chronic inflammation and granuloma formation around irritating foreign bodies.Prosthesis Failure: Malfunction of implantation shunts, valves, etc., and prosthesis loosening, migration, and breaking.Ultrasonography, Doppler, Duplex: Ultrasonography applying the Doppler effect combined with real-time imaging. The real-time image is created by rapid movement of the ultrasound beam. A powerful advantage of this technique is the ability to estimate the velocity of flow from the Doppler shift frequency.Scleral Diseases: General disorders of the sclera or white of the eye. They may include anatomic, embryologic, degenerative, or pigmentation defects.Craniotomy: Any operation on the cranium or incision into the cranium. (Dorland, 28th ed)Diaphragmatic Eventration: A congenital abnormality characterized by the elevation of the DIAPHRAGM dome. It is the result of a thinned diaphragmatic muscle and injured PHRENIC NERVE, allowing the intra-abdominal viscera to push the diaphragm upward against the LUNG.Transplants: Organs, tissues, or cells taken from the body for grafting into another area of the same body or into another individual.Device Removal: Removal of an implanted therapeutic or prosthetic device.Vena Cava, Inferior: The venous trunk which receives blood from the lower extremities and from the pelvic and abdominal organs.Prospective Studies: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.Microscopy, Electron, Scanning: Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.Tissue Adhesives: Substances used to cause adherence of tissue to tissue or tissue to non-tissue surfaces, as for prostheses.Lower Extremity: The region of the lower limb in animals, extending from the gluteal region to the FOOT, and including the BUTTOCKS; HIP; and LEG.Angioplasty: Reconstruction or repair of a blood vessel, which includes the widening of a pathological narrowing of an artery or vein by the removal of atheromatous plaque material and/or the endothelial lining as well, or by dilatation (BALLOON ANGIOPLASTY) to compress an ATHEROMA. Except for ENDARTERECTOMY, usually these procedures are performed via catheterization as minimally invasive ENDOVASCULAR PROCEDURES.Tensile Strength: The maximum stress a material subjected to a stretching load can withstand without tearing. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p2001)Silicones: A broad family of synthetic organosiloxane polymers containing a repeating silicon-oxygen backbone with organic side groups attached via carbon-silicon bonds. Depending on their structure, they are classified as liquids, gels, and elastomers. (From Merck Index, 12th ed)Reconstructive Surgical Procedures: Procedures used to reconstruct, restore, or improve defective, damaged, or missing structures.Vascular Neoplasms: Neoplasms located in the vasculature system, such as ARTERIES and VEINS. They are differentiated from neoplasms of vascular tissue (NEOPLASMS, VASCULAR TISSUE), such as ANGIOFIBROMA or HEMANGIOMA.Prosthesis Implantation: Surgical insertion of a prosthesis.Thrombectomy: Surgical removal of an obstructing clot or foreign material from a blood vessel at the point of its formation. Removal of a clot arising from a distant site is called EMBOLECTOMY.Surface Properties: Characteristics or attributes of the outer boundaries of objects, including molecules.Angioplasty, Balloon: Use of a balloon catheter for dilation of an occluded artery. It is used in treatment of arterial occlusive diseases, including renal artery stenosis and arterial occlusions in the leg. For the specific technique of BALLOON DILATION in coronary arteries, ANGIOPLASTY, BALLOON, CORONARY is available.Polyglycolic Acid: A biocompatible polymer used as a surgical suture material.Carotid Stenosis: Narrowing or stricture of any part of the CAROTID ARTERIES, most often due to atherosclerotic plaque formation. Ulcerations may form in atherosclerotic plaques and induce THROMBUS formation. Platelet or cholesterol emboli may arise from stenotic carotid lesions and induce a TRANSIENT ISCHEMIC ATTACK; CEREBROVASCULAR ACCIDENT; or temporary blindness (AMAUROSIS FUGAX). (From Adams et al., Principles of Neurology, 6th ed, pp 822-3)Pericardium: A conical fibro-serous sac surrounding the HEART and the roots of the great vessels (AORTA; VENAE CAVAE; PULMONARY ARTERY). Pericardium consists of two sacs: the outer fibrous pericardium and the inner serous pericardium. The latter consists of an outer parietal layer facing the fibrous pericardium, and an inner visceral layer (epicardium) resting next to the heart, and a pericardial cavity between these two layers.Aortic Aneurysm, Abdominal: An abnormal balloon- or sac-like dilatation in the wall of the ABDOMINAL AORTA which gives rise to the visceral, the parietal, and the terminal (iliac) branches below the aortic hiatus at the diaphragm.Polyesters: Polymers of organic acids and alcohols, with ester linkages--usually polyethylene terephthalate; can be cured into hard plastic, films or tapes, or fibers which can be woven into fabrics, meshes or velours.